granicus.if.org Git - postgresql/blob - src/backend/utils/misc/guc.c

   1 /*--------------------------------------------------------------------
   2  * guc.c
   3  *
   4  * Support for grand unified configuration scheme, including SET
   5  * command, configuration file, and command line options.
   6  * See src/backend/utils/misc/README for more information.
   7  *
   8  *
   9  * Copyright (c) 2000-2011, PostgreSQL Global Development Group
  10  * Written by Peter Eisentraut <peter_e@gmx.net>.
  11  *
  12  * IDENTIFICATION
  13  *        src/backend/utils/misc/guc.c
  14  *
  15  *--------------------------------------------------------------------
  16  */
  17 #include "postgres.h"
  18
  19 #include <ctype.h>
  20 #include <float.h>
  21 #include <math.h>
  22 #include <limits.h>
  23 #include <unistd.h>
  24 #include <sys/stat.h>
  25 #ifdef HAVE_SYSLOG
  26 #include <syslog.h>
  27 #endif
  28
  29 #include "access/gin.h"
  30 #include "access/transam.h"
  31 #include "access/twophase.h"
  32 #include "access/xact.h"
  33 #include "catalog/namespace.h"
  34 #include "commands/async.h"
  35 #include "commands/prepare.h"
  36 #include "commands/vacuum.h"
  37 #include "commands/variable.h"
  38 #include "commands/trigger.h"
  39 #include "funcapi.h"
  40 #include "libpq/auth.h"
  41 #include "libpq/be-fsstubs.h"
  42 #include "libpq/pqformat.h"
  43 #include "miscadmin.h"
  44 #include "optimizer/cost.h"
  45 #include "optimizer/geqo.h"
  46 #include "optimizer/paths.h"
  47 #include "optimizer/planmain.h"
  48 #include "parser/parse_expr.h"
  49 #include "parser/parse_type.h"
  50 #include "parser/parser.h"
  51 #include "parser/scansup.h"
  52 #include "pgstat.h"
  53 #include "postmaster/autovacuum.h"
  54 #include "postmaster/bgwriter.h"
  55 #include "postmaster/postmaster.h"
  56 #include "postmaster/syslogger.h"
  57 #include "postmaster/walwriter.h"
  58 #include "replication/syncrep.h"
  59 #include "replication/walreceiver.h"
  60 #include "replication/walsender.h"
  61 #include "storage/bufmgr.h"
  62 #include "storage/standby.h"
  63 #include "storage/fd.h"
  64 #include "storage/predicate.h"
  65 #include "tcop/tcopprot.h"
  66 #include "tsearch/ts_cache.h"
  67 #include "utils/builtins.h"
  68 #include "utils/bytea.h"
  69 #include "utils/guc_tables.h"
  70 #include "utils/memutils.h"
  71 #include "utils/pg_locale.h"
  72 #include "utils/plancache.h"
  73 #include "utils/portal.h"
  74 #include "utils/ps_status.h"
  75 #include "utils/snapmgr.h"
  76 #include "utils/tzparser.h"
  77 #include "utils/xml.h"
  78
  79 #ifndef PG_KRB_SRVTAB
  80 #define PG_KRB_SRVTAB ""
  81 #endif
  82 #ifndef PG_KRB_SRVNAM
  83 #define PG_KRB_SRVNAM ""
  84 #endif
  85
  86 #define CONFIG_FILENAME "postgresql.conf"
  87 #define HBA_FILENAME    "pg_hba.conf"
  88 #define IDENT_FILENAME  "pg_ident.conf"
  89
  90 #ifdef EXEC_BACKEND
  91 #define CONFIG_EXEC_PARAMS "global/config_exec_params"
  92 #define CONFIG_EXEC_PARAMS_NEW "global/config_exec_params.new"
  93 #endif
  94
  95 /* upper limit for GUC variables measured in kilobytes of memory */
  96 /* note that various places assume the byte size fits in a "long" variable */
  97 #if SIZEOF_SIZE_T > 4 && SIZEOF_LONG > 4
  98 #define MAX_KILOBYTES   INT_MAX
  99 #else
 100 #define MAX_KILOBYTES   (INT_MAX / 1024)
 101 #endif
 102
 103 /*
 104  * Note: MAX_BACKENDS is limited to 2^23-1 because inval.c stores the
 105  * backend ID as a 3-byte signed integer.  Even if that limitation were
 106  * removed, we still could not exceed INT_MAX/4 because some places compute
 107  * 4*MaxBackends without any overflow check.  This is rechecked in
 108  * check_maxconnections, since MaxBackends is computed as MaxConnections
 109  * plus autovacuum_max_workers plus one (for the autovacuum launcher).
 110  */
 111 #define MAX_BACKENDS    0x7fffff
 112
 113 #define KB_PER_MB (1024)
 114 #define KB_PER_GB (1024*1024)
 115
 116 #define MS_PER_S 1000
 117 #define S_PER_MIN 60
 118 #define MS_PER_MIN (1000 * 60)
 119 #define MIN_PER_H 60
 120 #define S_PER_H (60 * 60)
 121 #define MS_PER_H (1000 * 60 * 60)
 122 #define MIN_PER_D (60 * 24)
 123 #define S_PER_D (60 * 60 * 24)
 124 #define MS_PER_D (1000 * 60 * 60 * 24)
 125
 126 /* XXX these should appear in other modules' header files */
 127 extern bool Log_disconnections;
 128 extern int      CommitDelay;
 129 extern int      CommitSiblings;
 130 extern char *default_tablespace;
 131 extern char *temp_tablespaces;
 132 extern bool synchronize_seqscans;
 133 extern bool fullPageWrites;
 134 extern int      ssl_renegotiation_limit;
 135 extern char *SSLCipherSuites;
 136
 137 #ifdef TRACE_SORT
 138 extern bool trace_sort;
 139 #endif
 140 #ifdef TRACE_SYNCSCAN
 141 extern bool trace_syncscan;
 142 #endif
 143 #ifdef DEBUG_BOUNDED_SORT
 144 extern bool optimize_bounded_sort;
 145 #endif
 146
 147 static int      GUC_check_errcode_value;
 148
 149 /* global variables for check hook support */
 150 char       *GUC_check_errmsg_string;
 151 char       *GUC_check_errdetail_string;
 152 char       *GUC_check_errhint_string;
 153
 154
 155 static void set_config_sourcefile(const char *name, char *sourcefile,
 156                                           int sourceline);
 157 static bool call_bool_check_hook(struct config_bool * conf, bool *newval,
 158                                          void **extra, GucSource source, int elevel);
 159 static bool call_int_check_hook(struct config_int * conf, int *newval,
 160                                         void **extra, GucSource source, int elevel);
 161 static bool call_real_check_hook(struct config_real * conf, double *newval,
 162                                          void **extra, GucSource source, int elevel);
 163 static bool call_string_check_hook(struct config_string * conf, char **newval,
 164                                            void **extra, GucSource source, int elevel);
 165 static bool call_enum_check_hook(struct config_enum * conf, int *newval,
 166                                          void **extra, GucSource source, int elevel);
 167
 168 static bool check_log_destination(char **newval, void **extra, GucSource source);
 169 static void assign_log_destination(const char *newval, void *extra);
 170
 171 #ifdef HAVE_SYSLOG
 172 static int      syslog_facility = LOG_LOCAL0;
 173 #else
 174 static int      syslog_facility = 0;
 175 #endif
 176
 177 static void assign_syslog_facility(int newval, void *extra);
 178 static void assign_syslog_ident(const char *newval, void *extra);
 179 static void assign_session_replication_role(int newval, void *extra);
 180 static bool check_temp_buffers(int *newval, void **extra, GucSource source);
 181 static bool check_phony_autocommit(bool *newval, void **extra, GucSource source);
 182 static bool check_debug_assertions(bool *newval, void **extra, GucSource source);
 183 static bool check_bonjour(bool *newval, void **extra, GucSource source);
 184 static bool check_ssl(bool *newval, void **extra, GucSource source);
 185 static bool check_stage_log_stats(bool *newval, void **extra, GucSource source);
 186 static bool check_log_stats(bool *newval, void **extra, GucSource source);
 187 static bool check_canonical_path(char **newval, void **extra, GucSource source);
 188 static bool check_timezone_abbreviations(char **newval, void **extra, GucSource source);
 189 static void assign_timezone_abbreviations(const char *newval, void *extra);
 190 static void pg_timezone_abbrev_initialize(void);
 191 static const char *show_archive_command(void);
 192 static void assign_tcp_keepalives_idle(int newval, void *extra);
 193 static void assign_tcp_keepalives_interval(int newval, void *extra);
 194 static void assign_tcp_keepalives_count(int newval, void *extra);
 195 static const char *show_tcp_keepalives_idle(void);
 196 static const char *show_tcp_keepalives_interval(void);
 197 static const char *show_tcp_keepalives_count(void);
 198 static bool check_maxconnections(int *newval, void **extra, GucSource source);
 199 static void assign_maxconnections(int newval, void *extra);
 200 static bool check_autovacuum_max_workers(int *newval, void **extra, GucSource source);
 201 static void assign_autovacuum_max_workers(int newval, void *extra);
 202 static bool check_effective_io_concurrency(int *newval, void **extra, GucSource source);
 203 static void assign_effective_io_concurrency(int newval, void *extra);
 204 static void assign_pgstat_temp_directory(const char *newval, void *extra);
 205 static bool check_application_name(char **newval, void **extra, GucSource source);
 206 static void assign_application_name(const char *newval, void *extra);
 207 static const char *show_unix_socket_permissions(void);
 208 static const char *show_log_file_mode(void);
 209
 210 static char *config_enum_get_options(struct config_enum * record,
 211                                                 const char *prefix, const char *suffix,
 212                                                 const char *separator);
 213
 214
 215 /*
 216  * Options for enum values defined in this module.
 217  *
 218  * NOTE! Option values may not contain double quotes!
 219  */
 220
 221 static const struct config_enum_entry bytea_output_options[] = {
 222         {"escape", BYTEA_OUTPUT_ESCAPE, false},
 223         {"hex", BYTEA_OUTPUT_HEX, false},
 224         {NULL, 0, false}
 225 };
 226
 227 /*
 228  * We have different sets for client and server message level options because
 229  * they sort slightly different (see "log" level)
 230  */
 231 static const struct config_enum_entry client_message_level_options[] = {
 232         {"debug", DEBUG2, true},
 233         {"debug5", DEBUG5, false},
 234         {"debug4", DEBUG4, false},
 235         {"debug3", DEBUG3, false},
 236         {"debug2", DEBUG2, false},
 237         {"debug1", DEBUG1, false},
 238         {"log", LOG, false},
 239         {"info", INFO, true},
 240         {"notice", NOTICE, false},
 241         {"warning", WARNING, false},
 242         {"error", ERROR, false},
 243         {"fatal", FATAL, true},
 244         {"panic", PANIC, true},
 245         {NULL, 0, false}
 246 };
 247
 248 static const struct config_enum_entry server_message_level_options[] = {
 249         {"debug", DEBUG2, true},
 250         {"debug5", DEBUG5, false},
 251         {"debug4", DEBUG4, false},
 252         {"debug3", DEBUG3, false},
 253         {"debug2", DEBUG2, false},
 254         {"debug1", DEBUG1, false},
 255         {"info", INFO, false},
 256         {"notice", NOTICE, false},
 257         {"warning", WARNING, false},
 258         {"error", ERROR, false},
 259         {"log", LOG, false},
 260         {"fatal", FATAL, false},
 261         {"panic", PANIC, false},
 262         {NULL, 0, false}
 263 };
 264
 265 static const struct config_enum_entry intervalstyle_options[] = {
 266         {"postgres", INTSTYLE_POSTGRES, false},
 267         {"postgres_verbose", INTSTYLE_POSTGRES_VERBOSE, false},
 268         {"sql_standard", INTSTYLE_SQL_STANDARD, false},
 269         {"iso_8601", INTSTYLE_ISO_8601, false},
 270         {NULL, 0, false}
 271 };
 272
 273 static const struct config_enum_entry log_error_verbosity_options[] = {
 274         {"terse", PGERROR_TERSE, false},
 275         {"default", PGERROR_DEFAULT, false},
 276         {"verbose", PGERROR_VERBOSE, false},
 277         {NULL, 0, false}
 278 };
 279
 280 static const struct config_enum_entry log_statement_options[] = {
 281         {"none", LOGSTMT_NONE, false},
 282         {"ddl", LOGSTMT_DDL, false},
 283         {"mod", LOGSTMT_MOD, false},
 284         {"all", LOGSTMT_ALL, false},
 285         {NULL, 0, false}
 286 };
 287
 288 static const struct config_enum_entry isolation_level_options[] = {
 289         {"serializable", XACT_SERIALIZABLE, false},
 290         {"repeatable read", XACT_REPEATABLE_READ, false},
 291         {"read committed", XACT_READ_COMMITTED, false},
 292         {"read uncommitted", XACT_READ_UNCOMMITTED, false},
 293         {NULL, 0}
 294 };
 295
 296 static const struct config_enum_entry session_replication_role_options[] = {
 297         {"origin", SESSION_REPLICATION_ROLE_ORIGIN, false},
 298         {"replica", SESSION_REPLICATION_ROLE_REPLICA, false},
 299         {"local", SESSION_REPLICATION_ROLE_LOCAL, false},
 300         {NULL, 0, false}
 301 };
 302
 303 static const struct config_enum_entry syslog_facility_options[] = {
 304 #ifdef HAVE_SYSLOG
 305         {"local0", LOG_LOCAL0, false},
 306         {"local1", LOG_LOCAL1, false},
 307         {"local2", LOG_LOCAL2, false},
 308         {"local3", LOG_LOCAL3, false},
 309         {"local4", LOG_LOCAL4, false},
 310         {"local5", LOG_LOCAL5, false},
 311         {"local6", LOG_LOCAL6, false},
 312         {"local7", LOG_LOCAL7, false},
 313 #else
 314         {"none", 0, false},
 315 #endif
 316         {NULL, 0}
 317 };
 318
 319 static const struct config_enum_entry track_function_options[] = {
 320         {"none", TRACK_FUNC_OFF, false},
 321         {"pl", TRACK_FUNC_PL, false},
 322         {"all", TRACK_FUNC_ALL, false},
 323         {NULL, 0, false}
 324 };
 325
 326 static const struct config_enum_entry xmlbinary_options[] = {
 327         {"base64", XMLBINARY_BASE64, false},
 328         {"hex", XMLBINARY_HEX, false},
 329         {NULL, 0, false}
 330 };
 331
 332 static const struct config_enum_entry xmloption_options[] = {
 333         {"content", XMLOPTION_CONTENT, false},
 334         {"document", XMLOPTION_DOCUMENT, false},
 335         {NULL, 0, false}
 336 };
 337
 338 /*
 339  * Although only "on", "off", and "safe_encoding" are documented, we
 340  * accept all the likely variants of "on" and "off".
 341  */
 342 static const struct config_enum_entry backslash_quote_options[] = {
 343         {"safe_encoding", BACKSLASH_QUOTE_SAFE_ENCODING, false},
 344         {"on", BACKSLASH_QUOTE_ON, false},
 345         {"off", BACKSLASH_QUOTE_OFF, false},
 346         {"true", BACKSLASH_QUOTE_ON, true},
 347         {"false", BACKSLASH_QUOTE_OFF, true},
 348         {"yes", BACKSLASH_QUOTE_ON, true},
 349         {"no", BACKSLASH_QUOTE_OFF, true},
 350         {"1", BACKSLASH_QUOTE_ON, true},
 351         {"0", BACKSLASH_QUOTE_OFF, true},
 352         {NULL, 0, false}
 353 };
 354
 355 /*
 356  * Although only "on", "off", and "partition" are documented, we
 357  * accept all the likely variants of "on" and "off".
 358  */
 359 static const struct config_enum_entry constraint_exclusion_options[] = {
 360         {"partition", CONSTRAINT_EXCLUSION_PARTITION, false},
 361         {"on", CONSTRAINT_EXCLUSION_ON, false},
 362         {"off", CONSTRAINT_EXCLUSION_OFF, false},
 363         {"true", CONSTRAINT_EXCLUSION_ON, true},
 364         {"false", CONSTRAINT_EXCLUSION_OFF, true},
 365         {"yes", CONSTRAINT_EXCLUSION_ON, true},
 366         {"no", CONSTRAINT_EXCLUSION_OFF, true},
 367         {"1", CONSTRAINT_EXCLUSION_ON, true},
 368         {"0", CONSTRAINT_EXCLUSION_OFF, true},
 369         {NULL, 0, false}
 370 };
 371
 372 /*
 373  * Although only "on", "off", and "local" are documented, we
 374  * accept all the likely variants of "on" and "off".
 375  */
 376 static const struct config_enum_entry synchronous_commit_options[] = {
 377         {"local", SYNCHRONOUS_COMMIT_LOCAL_FLUSH, false},
 378         {"on", SYNCHRONOUS_COMMIT_ON, false},
 379         {"off", SYNCHRONOUS_COMMIT_OFF, false},
 380         {"true", SYNCHRONOUS_COMMIT_ON, true},
 381         {"false", SYNCHRONOUS_COMMIT_OFF, true},
 382         {"yes", SYNCHRONOUS_COMMIT_ON, true},
 383         {"no", SYNCHRONOUS_COMMIT_OFF, true},
 384         {"1", SYNCHRONOUS_COMMIT_ON, true},
 385         {"0", SYNCHRONOUS_COMMIT_OFF, true},
 386         {NULL, 0, false}
 387 };
 388
 389 /*
 390  * Options for enum values stored in other modules
 391  */
 392 extern const struct config_enum_entry wal_level_options[];
 393 extern const struct config_enum_entry sync_method_options[];
 394
 395 /*
 396  * GUC option variables that are exported from this module
 397  */
 398 #ifdef USE_ASSERT_CHECKING
 399 bool            assert_enabled = true;
 400 #else
 401 bool            assert_enabled = false;
 402 #endif
 403 bool            log_duration = false;
 404 bool            Debug_print_plan = false;
 405 bool            Debug_print_parse = false;
 406 bool            Debug_print_rewritten = false;
 407 bool            Debug_pretty_print = true;
 408
 409 bool            log_parser_stats = false;
 410 bool            log_planner_stats = false;
 411 bool            log_executor_stats = false;
 412 bool            log_statement_stats = false;            /* this is sort of all three
 413                                                                                                  * above together */
 414 bool            log_btree_build_stats = false;
 415 char       *event_source;
 416
 417 bool            check_function_bodies = true;
 418 bool            default_with_oids = false;
 419 bool            SQL_inheritance = true;
 420
 421 bool            Password_encryption = true;
 422
 423 int                     log_min_error_statement = ERROR;
 424 int                     log_min_messages = WARNING;
 425 int                     client_min_messages = NOTICE;
 426 int                     log_min_duration_statement = -1;
 427 int                     log_temp_files = -1;
 428 int                     trace_recovery_messages = LOG;
 429
 430 int                     temp_file_limit = -1;
 431
 432 int                     num_temp_buffers = 1024;
 433
 434 char       *data_directory;
 435 char       *ConfigFileName;
 436 char       *HbaFileName;
 437 char       *IdentFileName;
 438 char       *external_pid_file;
 439
 440 char       *pgstat_temp_directory;
 441
 442 char       *application_name;
 443
 444 int                     tcp_keepalives_idle;
 445 int                     tcp_keepalives_interval;
 446 int                     tcp_keepalives_count;
 447
 448 /*
 449  * These variables are all dummies that don't do anything, except in some
 450  * cases provide the value for SHOW to display.  The real state is elsewhere
 451  * and is kept in sync by assign_hooks.
 452  */
 453 static char *log_destination_string;
 454
 455 static char *syslog_ident_str;
 456 static bool phony_autocommit;
 457 static bool session_auth_is_superuser;
 458 static double phony_random_seed;
 459 static char *client_encoding_string;
 460 static char *datestyle_string;
 461 static char *locale_collate;
 462 static char *locale_ctype;
 463 static char *server_encoding_string;
 464 static char *server_version_string;
 465 static int      server_version_num;
 466 static char *timezone_string;
 467 static char *log_timezone_string;
 468 static char *timezone_abbreviations_string;
 469 static char *XactIsoLevel_string;
 470 static char *session_authorization_string;
 471 static int      max_function_args;
 472 static int      max_index_keys;
 473 static int      max_identifier_length;
 474 static int      block_size;
 475 static int      segment_size;
 476 static int      wal_block_size;
 477 static int      wal_segment_size;
 478 static bool integer_datetimes;
 479 static int      effective_io_concurrency;
 480
 481 /* should be static, but commands/variable.c needs to get at this */
 482 char       *role_string;
 483
 484
 485 /*
 486  * Displayable names for context types (enum GucContext)
 487  *
 488  * Note: these strings are deliberately not localized.
 489  */
 490 const char *const GucContext_Names[] =
 491 {
 492          /* PGC_INTERNAL */ "internal",
 493          /* PGC_POSTMASTER */ "postmaster",
 494          /* PGC_SIGHUP */ "sighup",
 495          /* PGC_BACKEND */ "backend",
 496          /* PGC_SUSET */ "superuser",
 497          /* PGC_USERSET */ "user"
 498 };
 499
 500 /*
 501  * Displayable names for source types (enum GucSource)
 502  *
 503  * Note: these strings are deliberately not localized.
 504  */
 505 const char *const GucSource_Names[] =
 506 {
 507          /* PGC_S_DEFAULT */ "default",
 508          /* PGC_S_DYNAMIC_DEFAULT */ "default",
 509          /* PGC_S_ENV_VAR */ "environment variable",
 510          /* PGC_S_FILE */ "configuration file",
 511          /* PGC_S_ARGV */ "command line",
 512          /* PGC_S_DATABASE */ "database",
 513          /* PGC_S_USER */ "user",
 514          /* PGC_S_DATABASE_USER */ "database user",
 515          /* PGC_S_CLIENT */ "client",
 516          /* PGC_S_OVERRIDE */ "override",
 517          /* PGC_S_INTERACTIVE */ "interactive",
 518          /* PGC_S_TEST */ "test",
 519          /* PGC_S_SESSION */ "session"
 520 };
 521
 522 /*
 523  * Displayable names for the groupings defined in enum config_group
 524  */
 525 const char *const config_group_names[] =
 526 {
 527         /* UNGROUPED */
 528         gettext_noop("Ungrouped"),
 529         /* FILE_LOCATIONS */
 530         gettext_noop("File Locations"),
 531         /* CONN_AUTH */
 532         gettext_noop("Connections and Authentication"),
 533         /* CONN_AUTH_SETTINGS */
 534         gettext_noop("Connections and Authentication / Connection Settings"),
 535         /* CONN_AUTH_SECURITY */
 536         gettext_noop("Connections and Authentication / Security and Authentication"),
 537         /* RESOURCES */
 538         gettext_noop("Resource Usage"),
 539         /* RESOURCES_MEM */
 540         gettext_noop("Resource Usage / Memory"),
 541         /* RESOURCES_DISK */
 542         gettext_noop("Resource Usage / Disk"),
 543         /* RESOURCES_KERNEL */
 544         gettext_noop("Resource Usage / Kernel Resources"),
 545         /* RESOURCES_VACUUM_DELAY */
 546         gettext_noop("Resource Usage / Cost-Based Vacuum Delay"),
 547         /* RESOURCES_BGWRITER */
 548         gettext_noop("Resource Usage / Background Writer"),
 549         /* RESOURCES_ASYNCHRONOUS */
 550         gettext_noop("Resource Usage / Asynchronous Behavior"),
 551         /* WAL */
 552         gettext_noop("Write-Ahead Log"),
 553         /* WAL_SETTINGS */
 554         gettext_noop("Write-Ahead Log / Settings"),
 555         /* WAL_CHECKPOINTS */
 556         gettext_noop("Write-Ahead Log / Checkpoints"),
 557         /* WAL_ARCHIVING */
 558         gettext_noop("Write-Ahead Log / Archiving"),
 559         /* REPLICATION */
 560         gettext_noop("Replication"),
 561         /* REPLICATION_SENDING */
 562         gettext_noop("Replication / Sending Servers"),
 563         /* REPLICATION_MASTER */
 564         gettext_noop("Replication / Master Server"),
 565         /* REPLICATION_STANDBY */
 566         gettext_noop("Replication / Standby Servers"),
 567         /* QUERY_TUNING */
 568         gettext_noop("Query Tuning"),
 569         /* QUERY_TUNING_METHOD */
 570         gettext_noop("Query Tuning / Planner Method Configuration"),
 571         /* QUERY_TUNING_COST */
 572         gettext_noop("Query Tuning / Planner Cost Constants"),
 573         /* QUERY_TUNING_GEQO */
 574         gettext_noop("Query Tuning / Genetic Query Optimizer"),
 575         /* QUERY_TUNING_OTHER */
 576         gettext_noop("Query Tuning / Other Planner Options"),
 577         /* LOGGING */
 578         gettext_noop("Reporting and Logging"),
 579         /* LOGGING_WHERE */
 580         gettext_noop("Reporting and Logging / Where to Log"),
 581         /* LOGGING_WHEN */
 582         gettext_noop("Reporting and Logging / When to Log"),
 583         /* LOGGING_WHAT */
 584         gettext_noop("Reporting and Logging / What to Log"),
 585         /* STATS */
 586         gettext_noop("Statistics"),
 587         /* STATS_MONITORING */
 588         gettext_noop("Statistics / Monitoring"),
 589         /* STATS_COLLECTOR */
 590         gettext_noop("Statistics / Query and Index Statistics Collector"),
 591         /* AUTOVACUUM */
 592         gettext_noop("Autovacuum"),
 593         /* CLIENT_CONN */
 594         gettext_noop("Client Connection Defaults"),
 595         /* CLIENT_CONN_STATEMENT */
 596         gettext_noop("Client Connection Defaults / Statement Behavior"),
 597         /* CLIENT_CONN_LOCALE */
 598         gettext_noop("Client Connection Defaults / Locale and Formatting"),
 599         /* CLIENT_CONN_OTHER */
 600         gettext_noop("Client Connection Defaults / Other Defaults"),
 601         /* LOCK_MANAGEMENT */
 602         gettext_noop("Lock Management"),
 603         /* COMPAT_OPTIONS */
 604         gettext_noop("Version and Platform Compatibility"),
 605         /* COMPAT_OPTIONS_PREVIOUS */
 606         gettext_noop("Version and Platform Compatibility / Previous PostgreSQL Versions"),
 607         /* COMPAT_OPTIONS_CLIENT */
 608         gettext_noop("Version and Platform Compatibility / Other Platforms and Clients"),
 609         /* ERROR_HANDLING */
 610         gettext_noop("Error Handling"),
 611         /* PRESET_OPTIONS */
 612         gettext_noop("Preset Options"),
 613         /* CUSTOM_OPTIONS */
 614         gettext_noop("Customized Options"),
 615         /* DEVELOPER_OPTIONS */
 616         gettext_noop("Developer Options"),
 617         /* help_config wants this array to be null-terminated */
 618         NULL
 619 };
 620
 621 /*
 622  * Displayable names for GUC variable types (enum config_type)
 623  *
 624  * Note: these strings are deliberately not localized.
 625  */
 626 const char *const config_type_names[] =
 627 {
 628          /* PGC_BOOL */ "bool",
 629          /* PGC_INT */ "integer",
 630          /* PGC_REAL */ "real",
 631          /* PGC_STRING */ "string",
 632          /* PGC_ENUM */ "enum"
 633 };
 634
 635
 636 /*
 637  * Contents of GUC tables
 638  *
 639  * See src/backend/utils/misc/README for design notes.
 640  *
 641  * TO ADD AN OPTION:
 642  *
 643  * 1. Declare a global variable of type bool, int, double, or char*
 644  *        and make use of it.
 645  *
 646  * 2. Decide at what times it's safe to set the option. See guc.h for
 647  *        details.
 648  *
 649  * 3. Decide on a name, a default value, upper and lower bounds (if
 650  *        applicable), etc.
 651  *
 652  * 4. Add a record below.
 653  *
 654  * 5. Add it to src/backend/utils/misc/postgresql.conf.sample, if
 655  *        appropriate.
 656  *
 657  * 6. Don't forget to document the option (at least in config.sgml).
 658  *
 659  * 7. If it's a new GUC_LIST option you must edit pg_dumpall.c to ensure
 660  *        it is not single quoted at dump time.
 661  */
 662
 663
 664 /******** option records follow ********/
 665
 666 static struct config_bool ConfigureNamesBool[] =
 667 {
 668         {
 669                 {"enable_seqscan", PGC_USERSET, QUERY_TUNING_METHOD,
 670                         gettext_noop("Enables the planner's use of sequential-scan plans."),
 671                         NULL
 672                 },
 673                 &enable_seqscan,
 674                 true,
 675                 NULL, NULL, NULL
 676         },
 677         {
 678                 {"enable_indexscan", PGC_USERSET, QUERY_TUNING_METHOD,
 679                         gettext_noop("Enables the planner's use of index-scan plans."),
 680                         NULL
 681                 },
 682                 &enable_indexscan,
 683                 true,
 684                 NULL, NULL, NULL
 685         },
 686         {
 687                 {"enable_indexonlyscan", PGC_USERSET, QUERY_TUNING_METHOD,
 688                         gettext_noop("Enables the planner's use of index-only-scan plans."),
 689                         NULL
 690                 },
 691                 &enable_indexonlyscan,
 692                 true,
 693                 NULL, NULL, NULL
 694         },
 695         {
 696                 {"enable_bitmapscan", PGC_USERSET, QUERY_TUNING_METHOD,
 697                         gettext_noop("Enables the planner's use of bitmap-scan plans."),
 698                         NULL
 699                 },
 700                 &enable_bitmapscan,
 701                 true,
 702                 NULL, NULL, NULL
 703         },
 704         {
 705                 {"enable_tidscan", PGC_USERSET, QUERY_TUNING_METHOD,
 706                         gettext_noop("Enables the planner's use of TID scan plans."),
 707                         NULL
 708                 },
 709                 &enable_tidscan,
 710                 true,
 711                 NULL, NULL, NULL
 712         },
 713         {
 714                 {"enable_sort", PGC_USERSET, QUERY_TUNING_METHOD,
 715                         gettext_noop("Enables the planner's use of explicit sort steps."),
 716                         NULL
 717                 },
 718                 &enable_sort,
 719                 true,
 720                 NULL, NULL, NULL
 721         },
 722         {
 723                 {"enable_hashagg", PGC_USERSET, QUERY_TUNING_METHOD,
 724                         gettext_noop("Enables the planner's use of hashed aggregation plans."),
 725                         NULL
 726                 },
 727                 &enable_hashagg,
 728                 true,
 729                 NULL, NULL, NULL
 730         },
 731         {
 732                 {"enable_material", PGC_USERSET, QUERY_TUNING_METHOD,
 733                         gettext_noop("Enables the planner's use of materialization."),
 734                         NULL
 735                 },
 736                 &enable_material,
 737                 true,
 738                 NULL, NULL, NULL
 739         },
 740         {
 741                 {"enable_nestloop", PGC_USERSET, QUERY_TUNING_METHOD,
 742                         gettext_noop("Enables the planner's use of nested-loop join plans."),
 743                         NULL
 744                 },
 745                 &enable_nestloop,
 746                 true,
 747                 NULL, NULL, NULL
 748         },
 749         {
 750                 {"enable_mergejoin", PGC_USERSET, QUERY_TUNING_METHOD,
 751                         gettext_noop("Enables the planner's use of merge join plans."),
 752                         NULL
 753                 },
 754                 &enable_mergejoin,
 755                 true,
 756                 NULL, NULL, NULL
 757         },
 758         {
 759                 {"enable_hashjoin", PGC_USERSET, QUERY_TUNING_METHOD,
 760                         gettext_noop("Enables the planner's use of hash join plans."),
 761                         NULL
 762                 },
 763                 &enable_hashjoin,
 764                 true,
 765                 NULL, NULL, NULL
 766         },
 767         {
 768                 {"geqo", PGC_USERSET, QUERY_TUNING_GEQO,
 769                         gettext_noop("Enables genetic query optimization."),
 770                         gettext_noop("This algorithm attempts to do planning without "
 771                                                  "exhaustive searching.")
 772                 },
 773                 &enable_geqo,
 774                 true,
 775                 NULL, NULL, NULL
 776         },
 777         {
 778                 /* Not for general use --- used by SET SESSION AUTHORIZATION */
 779                 {"is_superuser", PGC_INTERNAL, UNGROUPED,
 780                         gettext_noop("Shows whether the current user is a superuser."),
 781                         NULL,
 782                         GUC_REPORT | GUC_NO_SHOW_ALL | GUC_NO_RESET_ALL | GUC_NOT_IN_SAMPLE | GUC_DISALLOW_IN_FILE
 783                 },
 784                 &session_auth_is_superuser,
 785                 false,
 786                 NULL, NULL, NULL
 787         },
 788         {
 789                 {"bonjour", PGC_POSTMASTER, CONN_AUTH_SETTINGS,
 790                         gettext_noop("Enables advertising the server via Bonjour."),
 791                         NULL
 792                 },
 793                 &enable_bonjour,
 794                 false,
 795                 check_bonjour, NULL, NULL
 796         },
 797         {
 798                 {"ssl", PGC_POSTMASTER, CONN_AUTH_SECURITY,
 799                         gettext_noop("Enables SSL connections."),
 800                         NULL
 801                 },
 802                 &EnableSSL,
 803                 false,
 804                 check_ssl, NULL, NULL
 805         },
 806         {
 807                 {"fsync", PGC_SIGHUP, WAL_SETTINGS,
 808                         gettext_noop("Forces synchronization of updates to disk."),
 809                         gettext_noop("The server will use the fsync() system call in several places to make "
 810                         "sure that updates are physically written to disk. This insures "
 811                                                  "that a database cluster will recover to a consistent state after "
 812                                                  "an operating system or hardware crash.")
 813                 },
 814                 &enableFsync,
 815                 true,
 816                 NULL, NULL, NULL
 817         },
 818         {
 819                 {"zero_damaged_pages", PGC_SUSET, DEVELOPER_OPTIONS,
 820                         gettext_noop("Continues processing past damaged page headers."),
 821                         gettext_noop("Detection of a damaged page header normally causes PostgreSQL to "
 822                                 "report an error, aborting the current transaction. Setting "
 823                                                  "zero_damaged_pages to true causes the system to instead report a "
 824                                                  "warning, zero out the damaged page, and continue processing. This "
 825                                                  "behavior will destroy data, namely all the rows on the damaged page."),
 826                         GUC_NOT_IN_SAMPLE
 827                 },
 828                 &zero_damaged_pages,
 829                 false,
 830                 NULL, NULL, NULL
 831         },
 832         {
 833                 {"full_page_writes", PGC_SIGHUP, WAL_SETTINGS,
 834                         gettext_noop("Writes full pages to WAL when first modified after a checkpoint."),
 835                         gettext_noop("A page write in process during an operating system crash might be "
 836                                                  "only partially written to disk.  During recovery, the row changes "
 837                           "stored in WAL are not enough to recover.  This option writes "
 838                                                  "pages when first modified after a checkpoint to WAL so full recovery "
 839                                                  "is possible.")
 840                 },
 841                 &fullPageWrites,
 842                 true,
 843                 NULL, NULL, NULL
 844         },
 845         {
 846                 {"log_checkpoints", PGC_SIGHUP, LOGGING_WHAT,
 847                         gettext_noop("Logs each checkpoint."),
 848                         NULL
 849                 },
 850                 &log_checkpoints,
 851                 false,
 852                 NULL, NULL, NULL
 853         },
 854         {
 855                 {"log_connections", PGC_BACKEND, LOGGING_WHAT,
 856                         gettext_noop("Logs each successful connection."),
 857                         NULL
 858                 },
 859                 &Log_connections,
 860                 false,
 861                 NULL, NULL, NULL
 862         },
 863         {
 864                 {"log_disconnections", PGC_BACKEND, LOGGING_WHAT,
 865                         gettext_noop("Logs end of a session, including duration."),
 866                         NULL
 867                 },
 868                 &Log_disconnections,
 869                 false,
 870                 NULL, NULL, NULL
 871         },
 872         {
 873                 {"debug_assertions", PGC_USERSET, DEVELOPER_OPTIONS,
 874                         gettext_noop("Turns on various assertion checks."),
 875                         gettext_noop("This is a debugging aid."),
 876                         GUC_NOT_IN_SAMPLE
 877                 },
 878                 &assert_enabled,
 879 #ifdef USE_ASSERT_CHECKING
 880                 true,
 881 #else
 882                 false,
 883 #endif
 884                 check_debug_assertions, NULL, NULL
 885         },
 886
 887         {
 888                 {"exit_on_error", PGC_USERSET, ERROR_HANDLING_OPTIONS,
 889                         gettext_noop("Terminate session on any error."),
 890                         NULL
 891                 },
 892                 &ExitOnAnyError,
 893                 false,
 894                 NULL, NULL, NULL
 895         },
 896         {
 897                 {"restart_after_crash", PGC_SIGHUP, ERROR_HANDLING_OPTIONS,
 898                         gettext_noop("Reinitialize server after backend crash."),
 899                         NULL
 900                 },
 901                 &restart_after_crash,
 902                 true,
 903                 NULL, NULL, NULL
 904         },
 905
 906         {
 907                 {"log_duration", PGC_SUSET, LOGGING_WHAT,
 908                         gettext_noop("Logs the duration of each completed SQL statement."),
 909                         NULL
 910                 },
 911                 &log_duration,
 912                 false,
 913                 NULL, NULL, NULL
 914         },
 915         {
 916                 {"debug_print_parse", PGC_USERSET, LOGGING_WHAT,
 917                         gettext_noop("Logs each query's parse tree."),
 918                         NULL
 919                 },
 920                 &Debug_print_parse,
 921                 false,
 922                 NULL, NULL, NULL
 923         },
 924         {
 925                 {"debug_print_rewritten", PGC_USERSET, LOGGING_WHAT,
 926                         gettext_noop("Logs each query's rewritten parse tree."),
 927                         NULL
 928                 },
 929                 &Debug_print_rewritten,
 930                 false,
 931                 NULL, NULL, NULL
 932         },
 933         {
 934                 {"debug_print_plan", PGC_USERSET, LOGGING_WHAT,
 935                         gettext_noop("Logs each query's execution plan."),
 936                         NULL
 937                 },
 938                 &Debug_print_plan,
 939                 false,
 940                 NULL, NULL, NULL
 941         },
 942         {
 943                 {"debug_pretty_print", PGC_USERSET, LOGGING_WHAT,
 944                         gettext_noop("Indents parse and plan tree displays."),
 945                         NULL
 946                 },
 947                 &Debug_pretty_print,
 948                 true,
 949                 NULL, NULL, NULL
 950         },
 951         {
 952                 {"log_parser_stats", PGC_SUSET, STATS_MONITORING,
 953                         gettext_noop("Writes parser performance statistics to the server log."),
 954                         NULL
 955                 },
 956                 &log_parser_stats,
 957                 false,
 958                 check_stage_log_stats, NULL, NULL
 959         },
 960         {
 961                 {"log_planner_stats", PGC_SUSET, STATS_MONITORING,
 962                         gettext_noop("Writes planner performance statistics to the server log."),
 963                         NULL
 964                 },
 965                 &log_planner_stats,
 966                 false,
 967                 check_stage_log_stats, NULL, NULL
 968         },
 969         {
 970                 {"log_executor_stats", PGC_SUSET, STATS_MONITORING,
 971                         gettext_noop("Writes executor performance statistics to the server log."),
 972                         NULL
 973                 },
 974                 &log_executor_stats,
 975                 false,
 976                 check_stage_log_stats, NULL, NULL
 977         },
 978         {
 979                 {"log_statement_stats", PGC_SUSET, STATS_MONITORING,
 980                         gettext_noop("Writes cumulative performance statistics to the server log."),
 981                         NULL
 982                 },
 983                 &log_statement_stats,
 984                 false,
 985                 check_log_stats, NULL, NULL
 986         },
 987 #ifdef BTREE_BUILD_STATS
 988         {
 989                 {"log_btree_build_stats", PGC_SUSET, DEVELOPER_OPTIONS,
 990                         gettext_noop("No description available."),
 991                         NULL,
 992                         GUC_NOT_IN_SAMPLE
 993                 },
 994                 &log_btree_build_stats,
 995                 false,
 996                 NULL, NULL, NULL
 997         },
 998 #endif
 999
1000         {
1001                 {"track_activities", PGC_SUSET, STATS_COLLECTOR,
1002                         gettext_noop("Collects information about executing commands."),
1003                         gettext_noop("Enables the collection of information on the currently "
1004                                                  "executing command of each session, along with "
1005                                                  "the time at which that command began execution.")
1006                 },
1007                 &pgstat_track_activities,
1008                 true,
1009                 NULL, NULL, NULL
1010         },
1011         {
1012                 {"track_counts", PGC_SUSET, STATS_COLLECTOR,
1013                         gettext_noop("Collects statistics on database activity."),
1014                         NULL
1015                 },
1016                 &pgstat_track_counts,
1017                 true,
1018                 NULL, NULL, NULL
1019         },
1020
1021         {
1022                 {"update_process_title", PGC_SUSET, STATS_COLLECTOR,
1023                         gettext_noop("Updates the process title to show the active SQL command."),
1024                         gettext_noop("Enables updating of the process title every time a new SQL command is received by the server.")
1025                 },
1026                 &update_process_title,
1027                 true,
1028                 NULL, NULL, NULL
1029         },
1030
1031         {
1032                 {"autovacuum", PGC_SIGHUP, AUTOVACUUM,
1033                         gettext_noop("Starts the autovacuum subprocess."),
1034                         NULL
1035                 },
1036                 &autovacuum_start_daemon,
1037                 true,
1038                 NULL, NULL, NULL
1039         },
1040
1041         {
1042                 {"trace_notify", PGC_USERSET, DEVELOPER_OPTIONS,
1043                         gettext_noop("Generates debugging output for LISTEN and NOTIFY."),
1044                         NULL,
1045                         GUC_NOT_IN_SAMPLE
1046                 },
1047                 &Trace_notify,
1048                 false,
1049                 NULL, NULL, NULL
1050         },
1051
1052 #ifdef LOCK_DEBUG
1053         {
1054                 {"trace_locks", PGC_SUSET, DEVELOPER_OPTIONS,
1055                         gettext_noop("No description available."),
1056                         NULL,
1057                         GUC_NOT_IN_SAMPLE
1058                 },
1059                 &Trace_locks,
1060                 false,
1061                 NULL, NULL, NULL
1062         },
1063         {
1064                 {"trace_lwlocks", PGC_SUSET, DEVELOPER_OPTIONS,
1065                         gettext_noop("No description available."),
1066                         NULL,
1067                         GUC_NOT_IN_SAMPLE
1068                 },
1069                 &Trace_lwlocks,
1070                 false,
1071                 NULL, NULL, NULL
1072         },
1073         {
1074                 {"debug_deadlocks", PGC_SUSET, DEVELOPER_OPTIONS,
1075                         gettext_noop("No description available."),
1076                         NULL,
1077                         GUC_NOT_IN_SAMPLE
1078                 },
1079                 &Debug_deadlocks,
1080                 false,
1081                 NULL, NULL, NULL
1082         },
1083 #endif
1084
1085         {
1086                 {"log_lock_waits", PGC_SUSET, LOGGING_WHAT,
1087                         gettext_noop("Logs long lock waits."),
1088                         NULL
1089                 },
1090                 &log_lock_waits,
1091                 false,
1092                 NULL, NULL, NULL
1093         },
1094
1095         {
1096                 {"log_hostname", PGC_SIGHUP, LOGGING_WHAT,
1097                         gettext_noop("Logs the host name in the connection logs."),
1098                         gettext_noop("By default, connection logs only show the IP address "
1099                                                  "of the connecting host. If you want them to show the host name you "
1100                           "can turn this on, but depending on your host name resolution "
1101                            "setup it might impose a non-negligible performance penalty.")
1102                 },
1103                 &log_hostname,
1104                 false,
1105                 NULL, NULL, NULL
1106         },
1107         {
1108                 {"sql_inheritance", PGC_USERSET, COMPAT_OPTIONS_PREVIOUS,
1109                         gettext_noop("Causes subtables to be included by default in various commands."),
1110                         NULL
1111                 },
1112                 &SQL_inheritance,
1113                 true,
1114                 NULL, NULL, NULL
1115         },
1116         {
1117                 {"password_encryption", PGC_USERSET, CONN_AUTH_SECURITY,
1118                         gettext_noop("Encrypt passwords."),
1119                         gettext_noop("When a password is specified in CREATE USER or "
1120                            "ALTER USER without writing either ENCRYPTED or UNENCRYPTED, "
1121                                                  "this parameter determines whether the password is to be encrypted.")
1122                 },
1123                 &Password_encryption,
1124                 true,
1125                 NULL, NULL, NULL
1126         },
1127         {
1128                 {"transform_null_equals", PGC_USERSET, COMPAT_OPTIONS_CLIENT,
1129                         gettext_noop("Treats \"expr=NULL\" as \"expr IS NULL\"."),
1130                         gettext_noop("When turned on, expressions of the form expr = NULL "
1131                            "(or NULL = expr) are treated as expr IS NULL, that is, they "
1132                                 "return true if expr evaluates to the null value, and false "
1133                            "otherwise. The correct behavior of expr = NULL is to always "
1134                                                  "return null (unknown).")
1135                 },
1136                 &Transform_null_equals,
1137                 false,
1138                 NULL, NULL, NULL
1139         },
1140         {
1141                 {"db_user_namespace", PGC_SIGHUP, CONN_AUTH_SECURITY,
1142                         gettext_noop("Enables per-database user names."),
1143                         NULL
1144                 },
1145                 &Db_user_namespace,
1146                 false,
1147                 NULL, NULL, NULL
1148         },
1149         {
1150                 /* only here for backwards compatibility */
1151                 {"autocommit", PGC_USERSET, CLIENT_CONN_STATEMENT,
1152                         gettext_noop("This parameter doesn't do anything."),
1153                         gettext_noop("It's just here so that we won't choke on SET AUTOCOMMIT TO ON from 7.3-vintage clients."),
1154                         GUC_NO_SHOW_ALL | GUC_NOT_IN_SAMPLE
1155                 },
1156                 &phony_autocommit,
1157                 true,
1158                 check_phony_autocommit, NULL, NULL
1159         },
1160         {
1161                 {"default_transaction_read_only", PGC_USERSET, CLIENT_CONN_STATEMENT,
1162                         gettext_noop("Sets the default read-only status of new transactions."),
1163                         NULL
1164                 },
1165                 &DefaultXactReadOnly,
1166                 false,
1167                 NULL, NULL, NULL
1168         },
1169         {
1170                 {"transaction_read_only", PGC_USERSET, CLIENT_CONN_STATEMENT,
1171                         gettext_noop("Sets the current transaction's read-only status."),
1172                         NULL,
1173                         GUC_NO_RESET_ALL | GUC_NOT_IN_SAMPLE | GUC_DISALLOW_IN_FILE
1174                 },
1175                 &XactReadOnly,
1176                 false,
1177                 check_transaction_read_only, NULL, NULL
1178         },
1179         {
1180                 {"default_transaction_deferrable", PGC_USERSET, CLIENT_CONN_STATEMENT,
1181                         gettext_noop("Sets the default deferrable status of new transactions."),
1182                         NULL
1183                 },
1184                 &DefaultXactDeferrable,
1185                 false,
1186                 NULL, NULL, NULL
1187         },
1188         {
1189                 {"transaction_deferrable", PGC_USERSET, CLIENT_CONN_STATEMENT,
1190                         gettext_noop("Whether to defer a read-only serializable transaction until it can be executed with no possible serialization failures."),
1191                         NULL,
1192                         GUC_NO_RESET_ALL | GUC_NOT_IN_SAMPLE | GUC_DISALLOW_IN_FILE
1193                 },
1194                 &XactDeferrable,
1195                 false,
1196                 check_transaction_deferrable, NULL, NULL
1197         },
1198         {
1199                 {"check_function_bodies", PGC_USERSET, CLIENT_CONN_STATEMENT,
1200                         gettext_noop("Check function bodies during CREATE FUNCTION."),
1201                         NULL
1202                 },
1203                 &check_function_bodies,
1204                 true,
1205                 NULL, NULL, NULL
1206         },
1207         {
1208                 {"array_nulls", PGC_USERSET, COMPAT_OPTIONS_PREVIOUS,
1209                         gettext_noop("Enable input of NULL elements in arrays."),
1210                         gettext_noop("When turned on, unquoted NULL in an array input "
1211                                                  "value means a null value; "
1212                                                  "otherwise it is taken literally.")
1213                 },
1214                 &Array_nulls,
1215                 true,
1216                 NULL, NULL, NULL
1217         },
1218         {
1219                 {"default_with_oids", PGC_USERSET, COMPAT_OPTIONS_PREVIOUS,
1220                         gettext_noop("Create new tables with OIDs by default."),
1221                         NULL
1222                 },
1223                 &default_with_oids,
1224                 false,
1225                 NULL, NULL, NULL
1226         },
1227         {
1228                 {"logging_collector", PGC_POSTMASTER, LOGGING_WHERE,
1229                         gettext_noop("Start a subprocess to capture stderr output and/or csvlogs into log files."),
1230                         NULL
1231                 },
1232                 &Logging_collector,
1233                 false,
1234                 NULL, NULL, NULL
1235         },
1236         {
1237                 {"log_truncate_on_rotation", PGC_SIGHUP, LOGGING_WHERE,
1238                         gettext_noop("Truncate existing log files of same name during log rotation."),
1239                         NULL
1240                 },
1241                 &Log_truncate_on_rotation,
1242                 false,
1243                 NULL, NULL, NULL
1244         },
1245
1246 #ifdef TRACE_SORT
1247         {
1248                 {"trace_sort", PGC_USERSET, DEVELOPER_OPTIONS,
1249                         gettext_noop("Emit information about resource usage in sorting."),
1250                         NULL,
1251                         GUC_NOT_IN_SAMPLE
1252                 },
1253                 &trace_sort,
1254                 false,
1255                 NULL, NULL, NULL
1256         },
1257 #endif
1258
1259 #ifdef TRACE_SYNCSCAN
1260         /* this is undocumented because not exposed in a standard build */
1261         {
1262                 {"trace_syncscan", PGC_USERSET, DEVELOPER_OPTIONS,
1263                         gettext_noop("Generate debugging output for synchronized scanning."),
1264                         NULL,
1265                         GUC_NOT_IN_SAMPLE
1266                 },
1267                 &trace_syncscan,
1268                 false,
1269                 NULL, NULL, NULL
1270         },
1271 #endif
1272
1273 #ifdef DEBUG_BOUNDED_SORT
1274         /* this is undocumented because not exposed in a standard build */
1275         {
1276                 {
1277                         "optimize_bounded_sort", PGC_USERSET, QUERY_TUNING_METHOD,
1278                         gettext_noop("Enable bounded sorting using heap sort."),
1279                         NULL,
1280                         GUC_NOT_IN_SAMPLE
1281                 },
1282                 &optimize_bounded_sort,
1283                 true,
1284                 NULL, NULL, NULL
1285         },
1286 #endif
1287
1288 #ifdef WAL_DEBUG
1289         {
1290                 {"wal_debug", PGC_SUSET, DEVELOPER_OPTIONS,
1291                         gettext_noop("Emit WAL-related debugging output."),
1292                         NULL,
1293                         GUC_NOT_IN_SAMPLE
1294                 },
1295                 &XLOG_DEBUG,
1296                 false,
1297                 NULL, NULL, NULL
1298         },
1299 #endif
1300
1301         {
1302                 {"integer_datetimes", PGC_INTERNAL, PRESET_OPTIONS,
1303                         gettext_noop("Datetimes are integer based."),
1304                         NULL,
1305                         GUC_REPORT | GUC_NOT_IN_SAMPLE | GUC_DISALLOW_IN_FILE
1306                 },
1307                 &integer_datetimes,
1308 #ifdef HAVE_INT64_TIMESTAMP
1309                 true,
1310 #else
1311                 false,
1312 #endif
1313                 NULL, NULL, NULL
1314         },
1315
1316         {
1317                 {"krb_caseins_users", PGC_SIGHUP, CONN_AUTH_SECURITY,
1318                         gettext_noop("Sets whether Kerberos and GSSAPI user names should be treated as case-insensitive."),
1319                         NULL
1320                 },
1321                 &pg_krb_caseins_users,
1322                 false,
1323                 NULL, NULL, NULL
1324         },
1325
1326         {
1327                 {"escape_string_warning", PGC_USERSET, COMPAT_OPTIONS_PREVIOUS,
1328                         gettext_noop("Warn about backslash escapes in ordinary string literals."),
1329                         NULL
1330                 },
1331                 &escape_string_warning,
1332                 true,
1333                 NULL, NULL, NULL
1334         },
1335
1336         {
1337                 {"standard_conforming_strings", PGC_USERSET, COMPAT_OPTIONS_PREVIOUS,
1338                         gettext_noop("Causes '...' strings to treat backslashes literally."),
1339                         NULL,
1340                         GUC_REPORT
1341                 },
1342                 &standard_conforming_strings,
1343                 true,
1344                 NULL, NULL, NULL
1345         },
1346
1347         {
1348                 {"synchronize_seqscans", PGC_USERSET, COMPAT_OPTIONS_PREVIOUS,
1349                         gettext_noop("Enable synchronized sequential scans."),
1350                         NULL
1351                 },
1352                 &synchronize_seqscans,
1353                 true,
1354                 NULL, NULL, NULL
1355         },
1356
1357         {
1358                 {"archive_mode", PGC_POSTMASTER, WAL_ARCHIVING,
1359                         gettext_noop("Allows archiving of WAL files using archive_command."),
1360                         NULL
1361                 },
1362                 &XLogArchiveMode,
1363                 false,
1364                 NULL, NULL, NULL
1365         },
1366
1367         {
1368                 {"hot_standby", PGC_POSTMASTER, REPLICATION_STANDBY,
1369                         gettext_noop("Allows connections and queries during recovery."),
1370                         NULL
1371                 },
1372                 &EnableHotStandby,
1373                 false,
1374                 NULL, NULL, NULL
1375         },
1376
1377         {
1378                 {"hot_standby_feedback", PGC_SIGHUP, REPLICATION_STANDBY,
1379                         gettext_noop("Allows feedback from a hot standby to the primary that will avoid query conflicts."),
1380                         NULL
1381                 },
1382                 &hot_standby_feedback,
1383                 false,
1384                 NULL, NULL, NULL
1385         },
1386
1387         {
1388                 {"allow_system_table_mods", PGC_POSTMASTER, DEVELOPER_OPTIONS,
1389                         gettext_noop("Allows modifications of the structure of system tables."),
1390                         NULL,
1391                         GUC_NOT_IN_SAMPLE
1392                 },
1393                 &allowSystemTableMods,
1394                 false,
1395                 NULL, NULL, NULL
1396         },
1397
1398         {
1399                 {"ignore_system_indexes", PGC_BACKEND, DEVELOPER_OPTIONS,
1400                         gettext_noop("Disables reading from system indexes."),
1401                         gettext_noop("It does not prevent updating the indexes, so it is safe "
1402                                                  "to use.  The worst consequence is slowness."),
1403                         GUC_NOT_IN_SAMPLE
1404                 },
1405                 &IgnoreSystemIndexes,
1406                 false,
1407                 NULL, NULL, NULL
1408         },
1409
1410         {
1411                 {"lo_compat_privileges", PGC_SUSET, COMPAT_OPTIONS_PREVIOUS,
1412                         gettext_noop("Enables backward compatibility mode for privilege checks on large objects."),
1413                         gettext_noop("Skips privilege checks when reading or modifying large objects, "
1414                                   "for compatibility with PostgreSQL releases prior to 9.0.")
1415                 },
1416                 &lo_compat_privileges,
1417                 false,
1418                 NULL, NULL, NULL
1419         },
1420
1421         {
1422                 {"quote_all_identifiers", PGC_USERSET, COMPAT_OPTIONS_PREVIOUS,
1423                         gettext_noop("When generating SQL fragments, quote all identifiers."),
1424                         NULL,
1425                 },
1426                 &quote_all_identifiers,
1427                 false,
1428                 NULL, NULL, NULL
1429         },
1430
1431         /* End-of-list marker */
1432         {
1433                 {NULL, 0, 0, NULL, NULL}, NULL, false, NULL, NULL, NULL
1434         }
1435 };
1436
1437
1438 static struct config_int ConfigureNamesInt[] =
1439 {
1440         {
1441                 {"archive_timeout", PGC_SIGHUP, WAL_ARCHIVING,
1442                         gettext_noop("Forces a switch to the next xlog file if a "
1443                                                  "new file has not been started within N seconds."),
1444                         NULL,
1445                         GUC_UNIT_S
1446                 },
1447                 &XLogArchiveTimeout,
1448                 0, 0, INT_MAX,
1449                 NULL, NULL, NULL
1450         },
1451         {
1452                 {"post_auth_delay", PGC_BACKEND, DEVELOPER_OPTIONS,
1453                         gettext_noop("Waits N seconds on connection startup after authentication."),
1454                         gettext_noop("This allows attaching a debugger to the process."),
1455                         GUC_NOT_IN_SAMPLE | GUC_UNIT_S
1456                 },
1457                 &PostAuthDelay,
1458                 0, 0, INT_MAX,
1459                 NULL, NULL, NULL
1460         },
1461         {
1462                 {"default_statistics_target", PGC_USERSET, QUERY_TUNING_OTHER,
1463                         gettext_noop("Sets the default statistics target."),
1464                         gettext_noop("This applies to table columns that have not had a "
1465                                 "column-specific target set via ALTER TABLE SET STATISTICS.")
1466                 },
1467                 &default_statistics_target,
1468                 100, 1, 10000,
1469                 NULL, NULL, NULL
1470         },
1471         {
1472                 {"from_collapse_limit", PGC_USERSET, QUERY_TUNING_OTHER,
1473                         gettext_noop("Sets the FROM-list size beyond which subqueries "
1474                                                  "are not collapsed."),
1475                         gettext_noop("The planner will merge subqueries into upper "
1476                                 "queries if the resulting FROM list would have no more than "
1477                                                  "this many items.")
1478                 },
1479                 &from_collapse_limit,
1480                 8, 1, INT_MAX,
1481                 NULL, NULL, NULL
1482         },
1483         {
1484                 {"join_collapse_limit", PGC_USERSET, QUERY_TUNING_OTHER,
1485                         gettext_noop("Sets the FROM-list size beyond which JOIN "
1486                                                  "constructs are not flattened."),
1487                         gettext_noop("The planner will flatten explicit JOIN "
1488                                                  "constructs into lists of FROM items whenever a "
1489                                                  "list of no more than this many items would result.")
1490                 },
1491                 &join_collapse_limit,
1492                 8, 1, INT_MAX,
1493                 NULL, NULL, NULL
1494         },
1495         {
1496                 {"geqo_threshold", PGC_USERSET, QUERY_TUNING_GEQO,
1497                         gettext_noop("Sets the threshold of FROM items beyond which GEQO is used."),
1498                         NULL
1499                 },
1500                 &geqo_threshold,
1501                 12, 2, INT_MAX,
1502                 NULL, NULL, NULL
1503         },
1504         {
1505                 {"geqo_effort", PGC_USERSET, QUERY_TUNING_GEQO,
1506                         gettext_noop("GEQO: effort is used to set the default for other GEQO parameters."),
1507                         NULL
1508                 },
1509                 &Geqo_effort,
1510                 DEFAULT_GEQO_EFFORT, MIN_GEQO_EFFORT, MAX_GEQO_EFFORT,
1511                 NULL, NULL, NULL
1512         },
1513         {
1514                 {"geqo_pool_size", PGC_USERSET, QUERY_TUNING_GEQO,
1515                         gettext_noop("GEQO: number of individuals in the population."),
1516                         gettext_noop("Zero selects a suitable default value.")
1517                 },
1518                 &Geqo_pool_size,
1519                 0, 0, INT_MAX,
1520                 NULL, NULL, NULL
1521         },
1522         {
1523                 {"geqo_generations", PGC_USERSET, QUERY_TUNING_GEQO,
1524                         gettext_noop("GEQO: number of iterations of the algorithm."),
1525                         gettext_noop("Zero selects a suitable default value.")
1526                 },
1527                 &Geqo_generations,
1528                 0, 0, INT_MAX,
1529                 NULL, NULL, NULL
1530         },
1531
1532         {
1533                 /* This is PGC_SUSET to prevent hiding from log_lock_waits. */
1534                 {"deadlock_timeout", PGC_SUSET, LOCK_MANAGEMENT,
1535                         gettext_noop("Sets the time to wait on a lock before checking for deadlock."),
1536                         NULL,
1537                         GUC_UNIT_MS
1538                 },
1539                 &DeadlockTimeout,
1540                 1000, 1, INT_MAX,
1541                 NULL, NULL, NULL
1542         },
1543
1544         {
1545                 {"max_standby_archive_delay", PGC_SIGHUP, REPLICATION_STANDBY,
1546                         gettext_noop("Sets the maximum delay before canceling queries when a hot standby server is processing archived WAL data."),
1547                         NULL,
1548                         GUC_UNIT_MS
1549                 },
1550                 &max_standby_archive_delay,
1551                 30 * 1000, -1, INT_MAX,
1552                 NULL, NULL, NULL
1553         },
1554
1555         {
1556                 {"max_standby_streaming_delay", PGC_SIGHUP, REPLICATION_STANDBY,
1557                         gettext_noop("Sets the maximum delay before canceling queries when a hot standby server is processing streamed WAL data."),
1558                         NULL,
1559                         GUC_UNIT_MS
1560                 },
1561                 &max_standby_streaming_delay,
1562                 30 * 1000, -1, INT_MAX,
1563                 NULL, NULL, NULL
1564         },
1565
1566         {
1567                 {"wal_receiver_status_interval", PGC_SIGHUP, REPLICATION_STANDBY,
1568                         gettext_noop("Sets the maximum interval between WAL receiver status reports to the primary."),
1569                         NULL,
1570                         GUC_UNIT_S
1571                 },
1572                 &wal_receiver_status_interval,
1573                 10, 0, INT_MAX / 1000,
1574                 NULL, NULL, NULL
1575         },
1576
1577         {
1578                 {"max_connections", PGC_POSTMASTER, CONN_AUTH_SETTINGS,
1579                         gettext_noop("Sets the maximum number of concurrent connections."),
1580                         NULL
1581                 },
1582                 &MaxConnections,
1583                 100, 1, MAX_BACKENDS,
1584                 check_maxconnections, assign_maxconnections, NULL
1585         },
1586
1587         {
1588                 {"superuser_reserved_connections", PGC_POSTMASTER, CONN_AUTH_SETTINGS,
1589                         gettext_noop("Sets the number of connection slots reserved for superusers."),
1590                         NULL
1591                 },
1592                 &ReservedBackends,
1593                 3, 0, MAX_BACKENDS,
1594                 NULL, NULL, NULL
1595         },
1596
1597         /*
1598          * We sometimes multiply the number of shared buffers by two without
1599          * checking for overflow, so we mustn't allow more than INT_MAX / 2.
1600          */
1601         {
1602                 {"shared_buffers", PGC_POSTMASTER, RESOURCES_MEM,
1603                         gettext_noop("Sets the number of shared memory buffers used by the server."),
1604                         NULL,
1605                         GUC_UNIT_BLOCKS
1606                 },
1607                 &NBuffers,
1608                 1024, 16, INT_MAX / 2,
1609                 NULL, NULL, NULL
1610         },
1611
1612         {
1613                 {"temp_buffers", PGC_USERSET, RESOURCES_MEM,
1614                         gettext_noop("Sets the maximum number of temporary buffers used by each session."),
1615                         NULL,
1616                         GUC_UNIT_BLOCKS
1617                 },
1618                 &num_temp_buffers,
1619                 1024, 100, INT_MAX / 2,
1620                 check_temp_buffers, NULL, NULL
1621         },
1622
1623         {
1624                 {"port", PGC_POSTMASTER, CONN_AUTH_SETTINGS,
1625                         gettext_noop("Sets the TCP port the server listens on."),
1626                         NULL
1627                 },
1628                 &PostPortNumber,
1629                 DEF_PGPORT, 1, 65535,
1630                 NULL, NULL, NULL
1631         },
1632
1633         {
1634                 {"unix_socket_permissions", PGC_POSTMASTER, CONN_AUTH_SETTINGS,
1635                         gettext_noop("Sets the access permissions of the Unix-domain socket."),
1636                         gettext_noop("Unix-domain sockets use the usual Unix file system "
1637                                                  "permission set. The parameter value is expected "
1638                                                  "to be a numeric mode specification in the form "
1639                                                  "accepted by the chmod and umask system calls. "
1640                                                  "(To use the customary octal format the number must "
1641                                                  "start with a 0 (zero).)")
1642                 },
1643                 &Unix_socket_permissions,
1644                 0777, 0000, 0777,
1645                 NULL, NULL, show_unix_socket_permissions
1646         },
1647
1648         {
1649                 {"log_file_mode", PGC_SIGHUP, LOGGING_WHERE,
1650                         gettext_noop("Sets the file permissions for log files."),
1651                         gettext_noop("The parameter value is expected "
1652                                                  "to be a numeric mode specification in the form "
1653                                                  "accepted by the chmod and umask system calls. "
1654                                                  "(To use the customary octal format the number must "
1655                                                  "start with a 0 (zero).)")
1656                 },
1657                 &Log_file_mode,
1658                 0600, 0000, 0777,
1659                 NULL, NULL, show_log_file_mode
1660         },
1661
1662         {
1663                 {"work_mem", PGC_USERSET, RESOURCES_MEM,
1664                         gettext_noop("Sets the maximum memory to be used for query workspaces."),
1665                         gettext_noop("This much memory can be used by each internal "
1666                                                  "sort operation and hash table before switching to "
1667                                                  "temporary disk files."),
1668                         GUC_UNIT_KB
1669                 },
1670                 &work_mem,
1671                 1024, 64, MAX_KILOBYTES,
1672                 NULL, NULL, NULL
1673         },
1674
1675         {
1676                 {"maintenance_work_mem", PGC_USERSET, RESOURCES_MEM,
1677                         gettext_noop("Sets the maximum memory to be used for maintenance operations."),
1678                         gettext_noop("This includes operations such as VACUUM and CREATE INDEX."),
1679                         GUC_UNIT_KB
1680                 },
1681                 &maintenance_work_mem,
1682                 16384, 1024, MAX_KILOBYTES,
1683                 NULL, NULL, NULL
1684         },
1685
1686         /*
1687          * We use the hopefully-safely-small value of 100kB as the compiled-in
1688          * default for max_stack_depth.  InitializeGUCOptions will increase it if
1689          * possible, depending on the actual platform-specific stack limit.
1690          */
1691         {
1692                 {"max_stack_depth", PGC_SUSET, RESOURCES_MEM,
1693                         gettext_noop("Sets the maximum stack depth, in kilobytes."),
1694                         NULL,
1695                         GUC_UNIT_KB
1696                 },
1697                 &max_stack_depth,
1698                 100, 100, MAX_KILOBYTES,
1699                 check_max_stack_depth, assign_max_stack_depth, NULL
1700         },
1701
1702         {
1703                 {"temp_file_limit", PGC_SUSET, RESOURCES_DISK,
1704                         gettext_noop("Limits the total size of all temp files used by each session."),
1705                         gettext_noop("-1 means no limit."),
1706                         GUC_UNIT_KB
1707                 },
1708                 &temp_file_limit,
1709                 -1, -1, INT_MAX,
1710                 NULL, NULL, NULL
1711         },
1712
1713         {
1714                 {"vacuum_cost_page_hit", PGC_USERSET, RESOURCES_VACUUM_DELAY,
1715                         gettext_noop("Vacuum cost for a page found in the buffer cache."),
1716                         NULL
1717                 },
1718                 &VacuumCostPageHit,
1719                 1, 0, 10000,
1720                 NULL, NULL, NULL
1721         },
1722
1723         {
1724                 {"vacuum_cost_page_miss", PGC_USERSET, RESOURCES_VACUUM_DELAY,
1725                         gettext_noop("Vacuum cost for a page not found in the buffer cache."),
1726                         NULL
1727                 },
1728                 &VacuumCostPageMiss,
1729                 10, 0, 10000,
1730                 NULL, NULL, NULL
1731         },
1732
1733         {
1734                 {"vacuum_cost_page_dirty", PGC_USERSET, RESOURCES_VACUUM_DELAY,
1735                         gettext_noop("Vacuum cost for a page dirtied by vacuum."),
1736                         NULL
1737                 },
1738                 &VacuumCostPageDirty,
1739                 20, 0, 10000,
1740                 NULL, NULL, NULL
1741         },
1742
1743         {
1744                 {"vacuum_cost_limit", PGC_USERSET, RESOURCES_VACUUM_DELAY,
1745                         gettext_noop("Vacuum cost amount available before napping."),
1746                         NULL
1747                 },
1748                 &VacuumCostLimit,
1749                 200, 1, 10000,
1750                 NULL, NULL, NULL
1751         },
1752
1753         {
1754                 {"vacuum_cost_delay", PGC_USERSET, RESOURCES_VACUUM_DELAY,
1755                         gettext_noop("Vacuum cost delay in milliseconds."),
1756                         NULL,
1757                         GUC_UNIT_MS
1758                 },
1759                 &VacuumCostDelay,
1760                 0, 0, 100,
1761                 NULL, NULL, NULL
1762         },
1763
1764         {
1765                 {"autovacuum_vacuum_cost_delay", PGC_SIGHUP, AUTOVACUUM,
1766                         gettext_noop("Vacuum cost delay in milliseconds, for autovacuum."),
1767                         NULL,
1768                         GUC_UNIT_MS
1769                 },
1770                 &autovacuum_vac_cost_delay,
1771                 20, -1, 100,
1772                 NULL, NULL, NULL
1773         },
1774
1775         {
1776                 {"autovacuum_vacuum_cost_limit", PGC_SIGHUP, AUTOVACUUM,
1777                         gettext_noop("Vacuum cost amount available before napping, for autovacuum."),
1778                         NULL
1779                 },
1780                 &autovacuum_vac_cost_limit,
1781                 -1, -1, 10000,
1782                 NULL, NULL, NULL
1783         },
1784
1785         {
1786                 {"max_files_per_process", PGC_POSTMASTER, RESOURCES_KERNEL,
1787                         gettext_noop("Sets the maximum number of simultaneously open files for each server process."),
1788                         NULL
1789                 },
1790                 &max_files_per_process,
1791                 1000, 25, INT_MAX,
1792                 NULL, NULL, NULL
1793         },
1794
1795         /*
1796          * See also CheckRequiredParameterValues() if this parameter changes
1797          */
1798         {
1799                 {"max_prepared_transactions", PGC_POSTMASTER, RESOURCES_MEM,
1800                         gettext_noop("Sets the maximum number of simultaneously prepared transactions."),
1801                         NULL
1802                 },
1803                 &max_prepared_xacts,
1804                 0, 0, MAX_BACKENDS,
1805                 NULL, NULL, NULL
1806         },
1807
1808 #ifdef LOCK_DEBUG
1809         {
1810                 {"trace_lock_oidmin", PGC_SUSET, DEVELOPER_OPTIONS,
1811                         gettext_noop("No description available."),
1812                         NULL,
1813                         GUC_NOT_IN_SAMPLE
1814                 },
1815                 &Trace_lock_oidmin,
1816                 FirstNormalObjectId, 0, INT_MAX,
1817                 NULL, NULL, NULL
1818         },
1819         {
1820                 {"trace_lock_table", PGC_SUSET, DEVELOPER_OPTIONS,
1821                         gettext_noop("No description available."),
1822                         NULL,
1823                         GUC_NOT_IN_SAMPLE
1824                 },
1825                 &Trace_lock_table,
1826                 0, 0, INT_MAX,
1827                 NULL, NULL, NULL
1828         },
1829 #endif
1830
1831         {
1832                 {"statement_timeout", PGC_USERSET, CLIENT_CONN_STATEMENT,
1833                         gettext_noop("Sets the maximum allowed duration of any statement."),
1834                         gettext_noop("A value of 0 turns off the timeout."),
1835                         GUC_UNIT_MS
1836                 },
1837                 &StatementTimeout,
1838                 0, 0, INT_MAX,
1839                 NULL, NULL, NULL
1840         },
1841
1842         {
1843                 {"vacuum_freeze_min_age", PGC_USERSET, CLIENT_CONN_STATEMENT,
1844                         gettext_noop("Minimum age at which VACUUM should freeze a table row."),
1845                         NULL
1846                 },
1847                 &vacuum_freeze_min_age,
1848                 50000000, 0, 1000000000,
1849                 NULL, NULL, NULL
1850         },
1851
1852         {
1853                 {"vacuum_freeze_table_age", PGC_USERSET, CLIENT_CONN_STATEMENT,
1854                         gettext_noop("Age at which VACUUM should scan whole table to freeze tuples."),
1855                         NULL
1856                 },
1857                 &vacuum_freeze_table_age,
1858                 150000000, 0, 2000000000,
1859                 NULL, NULL, NULL
1860         },
1861
1862         {
1863                 {"vacuum_defer_cleanup_age", PGC_SIGHUP, REPLICATION_MASTER,
1864                         gettext_noop("Number of transactions by which VACUUM and HOT cleanup should be deferred, if any."),
1865                         NULL
1866                 },
1867                 &vacuum_defer_cleanup_age,
1868                 0, 0, 1000000,
1869                 NULL, NULL, NULL
1870         },
1871
1872         /*
1873          * See also CheckRequiredParameterValues() if this parameter changes
1874          */
1875         {
1876                 {"max_locks_per_transaction", PGC_POSTMASTER, LOCK_MANAGEMENT,
1877                         gettext_noop("Sets the maximum number of locks per transaction."),
1878                         gettext_noop("The shared lock table is sized on the assumption that "
1879                           "at most max_locks_per_transaction * max_connections distinct "
1880                                                  "objects will need to be locked at any one time.")
1881                 },
1882                 &max_locks_per_xact,
1883                 64, 10, INT_MAX,
1884                 NULL, NULL, NULL
1885         },
1886
1887         {
1888                 {"max_pred_locks_per_transaction", PGC_POSTMASTER, LOCK_MANAGEMENT,
1889                         gettext_noop("Sets the maximum number of predicate locks per transaction."),
1890                         gettext_noop("The shared predicate lock table is sized on the assumption that "
1891                                                  "at most max_pred_locks_per_transaction * max_connections distinct "
1892                                                  "objects will need to be locked at any one time.")
1893                 },
1894                 &max_predicate_locks_per_xact,
1895                 64, 10, INT_MAX,
1896                 NULL, NULL, NULL
1897         },
1898
1899         {
1900                 {"authentication_timeout", PGC_SIGHUP, CONN_AUTH_SECURITY,
1901                         gettext_noop("Sets the maximum allowed time to complete client authentication."),
1902                         NULL,
1903                         GUC_UNIT_S
1904                 },
1905                 &AuthenticationTimeout,
1906                 60, 1, 600,
1907                 NULL, NULL, NULL
1908         },
1909
1910         {
1911                 /* Not for general use */
1912                 {"pre_auth_delay", PGC_SIGHUP, DEVELOPER_OPTIONS,
1913                         gettext_noop("Waits N seconds on connection startup before authentication."),
1914                         gettext_noop("This allows attaching a debugger to the process."),
1915                         GUC_NOT_IN_SAMPLE | GUC_UNIT_S
1916                 },
1917                 &PreAuthDelay,
1918                 0, 0, 60,
1919                 NULL, NULL, NULL
1920         },
1921
1922         {
1923                 {"wal_keep_segments", PGC_SIGHUP, REPLICATION_SENDING,
1924                         gettext_noop("Sets the number of WAL files held for standby servers."),
1925                         NULL
1926                 },
1927                 &wal_keep_segments,
1928                 0, 0, INT_MAX,
1929                 NULL, NULL, NULL
1930         },
1931
1932         {
1933                 {"checkpoint_segments", PGC_SIGHUP, WAL_CHECKPOINTS,
1934                         gettext_noop("Sets the maximum distance in log segments between automatic WAL checkpoints."),
1935                         NULL
1936                 },
1937                 &CheckPointSegments,
1938                 3, 1, INT_MAX,
1939                 NULL, NULL, NULL
1940         },
1941
1942         {
1943                 {"checkpoint_timeout", PGC_SIGHUP, WAL_CHECKPOINTS,
1944                         gettext_noop("Sets the maximum time between automatic WAL checkpoints."),
1945                         NULL,
1946                         GUC_UNIT_S
1947                 },
1948                 &CheckPointTimeout,
1949                 300, 30, 3600,
1950                 NULL, NULL, NULL
1951         },
1952
1953         {
1954                 {"checkpoint_warning", PGC_SIGHUP, WAL_CHECKPOINTS,
1955                         gettext_noop("Enables warnings if checkpoint segments are filled more "
1956                                                  "frequently than this."),
1957                         gettext_noop("Write a message to the server log if checkpoints "
1958                         "caused by the filling of checkpoint segment files happens more "
1959                                                  "frequently than this number of seconds. Zero turns off the warning."),
1960                         GUC_UNIT_S
1961                 },
1962                 &CheckPointWarning,
1963                 30, 0, INT_MAX,
1964                 NULL, NULL, NULL
1965         },
1966
1967         {
1968                 {"wal_buffers", PGC_POSTMASTER, WAL_SETTINGS,
1969                         gettext_noop("Sets the number of disk-page buffers in shared memory for WAL."),
1970                         NULL,
1971                         GUC_UNIT_XBLOCKS
1972                 },
1973                 &XLOGbuffers,
1974                 -1, -1, INT_MAX,
1975                 check_wal_buffers, NULL, NULL
1976         },
1977
1978         {
1979                 {"wal_writer_delay", PGC_SIGHUP, WAL_SETTINGS,
1980                         gettext_noop("WAL writer sleep time between WAL flushes."),
1981                         NULL,
1982                         GUC_UNIT_MS
1983                 },
1984                 &WalWriterDelay,
1985                 200, 1, 10000,
1986                 NULL, NULL, NULL
1987         },
1988
1989         {
1990                 /* see max_connections */
1991                 {"max_wal_senders", PGC_POSTMASTER, REPLICATION_SENDING,
1992                         gettext_noop("Sets the maximum number of simultaneously running WAL sender processes."),
1993                         NULL
1994                 },
1995                 &max_wal_senders,
1996                 0, 0, MAX_BACKENDS,
1997                 NULL, NULL, NULL
1998         },
1999
2000         {
2001                 {"replication_timeout", PGC_SIGHUP, REPLICATION_SENDING,
2002                         gettext_noop("Sets the maximum time to wait for WAL replication."),
2003                         NULL,
2004                         GUC_UNIT_MS
2005                 },
2006                 &replication_timeout,
2007                 60 * 1000, 0, INT_MAX,
2008                 NULL, NULL, NULL
2009         },
2010
2011         {
2012                 {"commit_delay", PGC_USERSET, WAL_SETTINGS,
2013                         gettext_noop("Sets the delay in microseconds between transaction commit and "
2014                                                  "flushing WAL to disk."),
2015                         NULL
2016                 },
2017                 &CommitDelay,
2018                 0, 0, 100000,
2019                 NULL, NULL, NULL
2020         },
2021
2022         {
2023                 {"commit_siblings", PGC_USERSET, WAL_SETTINGS,
2024                         gettext_noop("Sets the minimum concurrent open transactions before performing "
2025                                                  "commit_delay."),
2026                         NULL
2027                 },
2028                 &CommitSiblings,
2029                 5, 0, 1000,
2030                 NULL, NULL, NULL
2031         },
2032
2033         {
2034                 {"extra_float_digits", PGC_USERSET, CLIENT_CONN_LOCALE,
2035                         gettext_noop("Sets the number of digits displayed for floating-point values."),
2036                         gettext_noop("This affects real, double precision, and geometric data types. "
2037                          "The parameter value is added to the standard number of digits "
2038                                                  "(FLT_DIG or DBL_DIG as appropriate).")
2039                 },
2040                 &extra_float_digits,
2041                 0, -15, 3,
2042                 NULL, NULL, NULL
2043         },
2044
2045         {
2046                 {"log_min_duration_statement", PGC_SUSET, LOGGING_WHEN,
2047                         gettext_noop("Sets the minimum execution time above which "
2048                                                  "statements will be logged."),
2049                         gettext_noop("Zero prints all queries. -1 turns this feature off."),
2050                         GUC_UNIT_MS
2051                 },
2052                 &log_min_duration_statement,
2053                 -1, -1, INT_MAX,
2054                 NULL, NULL, NULL
2055         },
2056
2057         {
2058                 {"log_autovacuum_min_duration", PGC_SIGHUP, LOGGING_WHAT,
2059                         gettext_noop("Sets the minimum execution time above which "
2060                                                  "autovacuum actions will be logged."),
2061                         gettext_noop("Zero prints all actions. -1 turns autovacuum logging off."),
2062                         GUC_UNIT_MS
2063                 },
2064                 &Log_autovacuum_min_duration,
2065                 -1, -1, INT_MAX,
2066                 NULL, NULL, NULL
2067         },
2068
2069         {
2070                 {"bgwriter_delay", PGC_SIGHUP, RESOURCES_BGWRITER,
2071                         gettext_noop("Background writer sleep time between rounds."),
2072                         NULL,
2073                         GUC_UNIT_MS
2074                 },
2075                 &BgWriterDelay,
2076                 200, 10, 10000,
2077                 NULL, NULL, NULL
2078         },
2079
2080         {
2081                 {"bgwriter_lru_maxpages", PGC_SIGHUP, RESOURCES_BGWRITER,
2082                         gettext_noop("Background writer maximum number of LRU pages to flush per round."),
2083                         NULL
2084                 },
2085                 &bgwriter_lru_maxpages,
2086                 100, 0, 1000,
2087                 NULL, NULL, NULL
2088         },
2089
2090         {
2091                 {"effective_io_concurrency",
2092 #ifdef USE_PREFETCH
2093                         PGC_USERSET,
2094 #else
2095                         PGC_INTERNAL,
2096 #endif
2097                         RESOURCES_ASYNCHRONOUS,
2098                         gettext_noop("Number of simultaneous requests that can be handled efficiently by the disk subsystem."),
2099                         gettext_noop("For RAID arrays, this should be approximately the number of drive spindles in the array.")
2100                 },
2101                 &effective_io_concurrency,
2102 #ifdef USE_PREFETCH
2103                 1, 0, 1000,
2104 #else
2105                 0, 0, 0,
2106 #endif
2107                 check_effective_io_concurrency, assign_effective_io_concurrency, NULL
2108         },
2109
2110         {
2111                 {"log_rotation_age", PGC_SIGHUP, LOGGING_WHERE,
2112                         gettext_noop("Automatic log file rotation will occur after N minutes."),
2113                         NULL,
2114                         GUC_UNIT_MIN
2115                 },
2116                 &Log_RotationAge,
2117                 HOURS_PER_DAY * MINS_PER_HOUR, 0, INT_MAX / MINS_PER_HOUR,
2118                 NULL, NULL, NULL
2119         },
2120
2121         {
2122                 {"log_rotation_size", PGC_SIGHUP, LOGGING_WHERE,
2123                         gettext_noop("Automatic log file rotation will occur after N kilobytes."),
2124                         NULL,
2125                         GUC_UNIT_KB
2126                 },
2127                 &Log_RotationSize,
2128                 10 * 1024, 0, INT_MAX / 1024,
2129                 NULL, NULL, NULL
2130         },
2131
2132         {
2133                 {"max_function_args", PGC_INTERNAL, PRESET_OPTIONS,
2134                         gettext_noop("Shows the maximum number of function arguments."),
2135                         NULL,
2136                         GUC_NOT_IN_SAMPLE | GUC_DISALLOW_IN_FILE
2137                 },
2138                 &max_function_args,
2139                 FUNC_MAX_ARGS, FUNC_MAX_ARGS, FUNC_MAX_ARGS,
2140                 NULL, NULL, NULL
2141         },
2142
2143         {
2144                 {"max_index_keys", PGC_INTERNAL, PRESET_OPTIONS,
2145                         gettext_noop("Shows the maximum number of index keys."),
2146                         NULL,
2147                         GUC_NOT_IN_SAMPLE | GUC_DISALLOW_IN_FILE
2148                 },
2149                 &max_index_keys,
2150                 INDEX_MAX_KEYS, INDEX_MAX_KEYS, INDEX_MAX_KEYS,
2151                 NULL, NULL, NULL
2152         },
2153
2154         {
2155                 {"max_identifier_length", PGC_INTERNAL, PRESET_OPTIONS,
2156                         gettext_noop("Shows the maximum identifier length."),
2157                         NULL,
2158                         GUC_NOT_IN_SAMPLE | GUC_DISALLOW_IN_FILE
2159                 },
2160                 &max_identifier_length,
2161                 NAMEDATALEN - 1, NAMEDATALEN - 1, NAMEDATALEN - 1,
2162                 NULL, NULL, NULL
2163         },
2164
2165         {
2166                 {"block_size", PGC_INTERNAL, PRESET_OPTIONS,
2167                         gettext_noop("Shows the size of a disk block."),
2168                         NULL,
2169                         GUC_NOT_IN_SAMPLE | GUC_DISALLOW_IN_FILE
2170                 },
2171                 &block_size,
2172                 BLCKSZ, BLCKSZ, BLCKSZ,
2173                 NULL, NULL, NULL
2174         },
2175
2176         {
2177                 {"segment_size", PGC_INTERNAL, PRESET_OPTIONS,
2178                         gettext_noop("Shows the number of pages per disk file."),
2179                         NULL,
2180                         GUC_UNIT_BLOCKS | GUC_NOT_IN_SAMPLE | GUC_DISALLOW_IN_FILE
2181                 },
2182                 &segment_size,
2183                 RELSEG_SIZE, RELSEG_SIZE, RELSEG_SIZE,
2184                 NULL, NULL, NULL
2185         },
2186
2187         {
2188                 {"wal_block_size", PGC_INTERNAL, PRESET_OPTIONS,
2189                         gettext_noop("Shows the block size in the write ahead log."),
2190                         NULL,
2191                         GUC_NOT_IN_SAMPLE | GUC_DISALLOW_IN_FILE
2192                 },
2193                 &wal_block_size,
2194                 XLOG_BLCKSZ, XLOG_BLCKSZ, XLOG_BLCKSZ,
2195                 NULL, NULL, NULL
2196         },
2197
2198         {
2199                 {"wal_segment_size", PGC_INTERNAL, PRESET_OPTIONS,
2200                         gettext_noop("Shows the number of pages per write ahead log segment."),
2201                         NULL,
2202                         GUC_UNIT_XBLOCKS | GUC_NOT_IN_SAMPLE | GUC_DISALLOW_IN_FILE
2203                 },
2204                 &wal_segment_size,
2205                 (XLOG_SEG_SIZE / XLOG_BLCKSZ),
2206                 (XLOG_SEG_SIZE / XLOG_BLCKSZ),
2207                 (XLOG_SEG_SIZE / XLOG_BLCKSZ),
2208                 NULL, NULL, NULL
2209         },
2210
2211         {
2212                 {"autovacuum_naptime", PGC_SIGHUP, AUTOVACUUM,
2213                         gettext_noop("Time to sleep between autovacuum runs."),
2214                         NULL,
2215                         GUC_UNIT_S
2216                 },
2217                 &autovacuum_naptime,
2218                 60, 1, INT_MAX / 1000,
2219                 NULL, NULL, NULL
2220         },
2221         {
2222                 {"autovacuum_vacuum_threshold", PGC_SIGHUP, AUTOVACUUM,
2223                         gettext_noop("Minimum number of tuple updates or deletes prior to vacuum."),
2224                         NULL
2225                 },
2226                 &autovacuum_vac_thresh,
2227                 50, 0, INT_MAX,
2228                 NULL, NULL, NULL
2229         },
2230         {
2231                 {"autovacuum_analyze_threshold", PGC_SIGHUP, AUTOVACUUM,
2232                         gettext_noop("Minimum number of tuple inserts, updates or deletes prior to analyze."),
2233                         NULL
2234                 },
2235                 &autovacuum_anl_thresh,
2236                 50, 0, INT_MAX,
2237                 NULL, NULL, NULL
2238         },
2239         {
2240                 /* see varsup.c for why this is PGC_POSTMASTER not PGC_SIGHUP */
2241                 {"autovacuum_freeze_max_age", PGC_POSTMASTER, AUTOVACUUM,
2242                         gettext_noop("Age at which to autovacuum a table to prevent transaction ID wraparound."),
2243                         NULL
2244                 },
2245                 &autovacuum_freeze_max_age,
2246                 /* see pg_resetxlog if you change the upper-limit value */
2247                 200000000, 100000000, 2000000000,
2248                 NULL, NULL, NULL
2249         },
2250         {
2251                 /* see max_connections */
2252                 {"autovacuum_max_workers", PGC_POSTMASTER, AUTOVACUUM,
2253                         gettext_noop("Sets the maximum number of simultaneously running autovacuum worker processes."),
2254                         NULL
2255                 },
2256                 &autovacuum_max_workers,
2257                 3, 1, MAX_BACKENDS,
2258                 check_autovacuum_max_workers, assign_autovacuum_max_workers, NULL
2259         },
2260
2261         {
2262                 {"tcp_keepalives_idle", PGC_USERSET, CLIENT_CONN_OTHER,
2263                         gettext_noop("Time between issuing TCP keepalives."),
2264                         gettext_noop("A value of 0 uses the system default."),
2265                         GUC_UNIT_S
2266                 },
2267                 &tcp_keepalives_idle,
2268                 0, 0, INT_MAX,
2269                 NULL, assign_tcp_keepalives_idle, show_tcp_keepalives_idle
2270         },
2271
2272         {
2273                 {"tcp_keepalives_interval", PGC_USERSET, CLIENT_CONN_OTHER,
2274                         gettext_noop("Time between TCP keepalive retransmits."),
2275                         gettext_noop("A value of 0 uses the system default."),
2276                         GUC_UNIT_S
2277                 },
2278                 &tcp_keepalives_interval,
2279                 0, 0, INT_MAX,
2280                 NULL, assign_tcp_keepalives_interval, show_tcp_keepalives_interval
2281         },
2282
2283         {
2284                 {"ssl_renegotiation_limit", PGC_USERSET, CONN_AUTH_SECURITY,
2285                         gettext_noop("Set the amount of traffic to send and receive before renegotiating the encryption keys."),
2286                         NULL,
2287                         GUC_UNIT_KB,
2288                 },
2289                 &ssl_renegotiation_limit,
2290                 512 * 1024, 0, MAX_KILOBYTES,
2291                 NULL, NULL, NULL
2292         },
2293
2294         {
2295                 {"tcp_keepalives_count", PGC_USERSET, CLIENT_CONN_OTHER,
2296                         gettext_noop("Maximum number of TCP keepalive retransmits."),
2297                         gettext_noop("This controls the number of consecutive keepalive retransmits that can be "
2298                                                  "lost before a connection is considered dead. A value of 0 uses the "
2299                                                  "system default."),
2300                 },
2301                 &tcp_keepalives_count,
2302                 0, 0, INT_MAX,
2303                 NULL, assign_tcp_keepalives_count, show_tcp_keepalives_count
2304         },
2305
2306         {
2307                 {"gin_fuzzy_search_limit", PGC_USERSET, CLIENT_CONN_OTHER,
2308                         gettext_noop("Sets the maximum allowed result for exact search by GIN."),
2309                         NULL,
2310                         0
2311                 },
2312                 &GinFuzzySearchLimit,
2313                 0, 0, INT_MAX,
2314                 NULL, NULL, NULL
2315         },
2316
2317         {
2318                 {"effective_cache_size", PGC_USERSET, QUERY_TUNING_COST,
2319                         gettext_noop("Sets the planner's assumption about the size of the disk cache."),
2320                         gettext_noop("That is, the portion of the kernel's disk cache that "
2321                                                  "will be used for PostgreSQL data files. This is measured in disk "
2322                                                  "pages, which are normally 8 kB each."),
2323                         GUC_UNIT_BLOCKS,
2324                 },
2325                 &effective_cache_size,
2326                 DEFAULT_EFFECTIVE_CACHE_SIZE, 1, INT_MAX,
2327                 NULL, NULL, NULL
2328         },
2329
2330         {
2331                 /* Can't be set in postgresql.conf */
2332                 {"server_version_num", PGC_INTERNAL, PRESET_OPTIONS,
2333                         gettext_noop("Shows the server version as an integer."),
2334                         NULL,
2335                         GUC_NOT_IN_SAMPLE | GUC_DISALLOW_IN_FILE
2336                 },
2337                 &server_version_num,
2338                 PG_VERSION_NUM, PG_VERSION_NUM, PG_VERSION_NUM,
2339                 NULL, NULL, NULL
2340         },
2341
2342         {
2343                 {"log_temp_files", PGC_SUSET, LOGGING_WHAT,
2344                         gettext_noop("Log the use of temporary files larger than this number of kilobytes."),
2345                         gettext_noop("Zero logs all files. The default is -1 (turning this feature off)."),
2346                         GUC_UNIT_KB
2347                 },
2348                 &log_temp_files,
2349                 -1, -1, INT_MAX,
2350                 NULL, NULL, NULL
2351         },
2352
2353         {
2354                 {"track_activity_query_size", PGC_POSTMASTER, RESOURCES_MEM,
2355                         gettext_noop("Sets the size reserved for pg_stat_activity.current_query, in bytes."),
2356                         NULL,
2357                 },
2358                 &pgstat_track_activity_query_size,
2359                 1024, 100, 102400,
2360                 NULL, NULL, NULL
2361         },
2362
2363         /* End-of-list marker */
2364         {
2365                 {NULL, 0, 0, NULL, NULL}, NULL, 0, 0, 0, NULL, NULL, NULL
2366         }
2367 };
2368
2369
2370 static struct config_real ConfigureNamesReal[] =
2371 {
2372         {
2373                 {"seq_page_cost", PGC_USERSET, QUERY_TUNING_COST,
2374                         gettext_noop("Sets the planner's estimate of the cost of a "
2375                                                  "sequentially fetched disk page."),
2376                         NULL
2377                 },
2378                 &seq_page_cost,
2379                 DEFAULT_SEQ_PAGE_COST, 0, DBL_MAX,
2380                 NULL, NULL, NULL
2381         },
2382         {
2383                 {"random_page_cost", PGC_USERSET, QUERY_TUNING_COST,
2384                         gettext_noop("Sets the planner's estimate of the cost of a "
2385                                                  "nonsequentially fetched disk page."),
2386                         NULL
2387                 },
2388                 &random_page_cost,
2389                 DEFAULT_RANDOM_PAGE_COST, 0, DBL_MAX,
2390                 NULL, NULL, NULL
2391         },
2392         {
2393                 {"cpu_tuple_cost", PGC_USERSET, QUERY_TUNING_COST,
2394                         gettext_noop("Sets the planner's estimate of the cost of "
2395                                                  "processing each tuple (row)."),
2396                         NULL
2397                 },
2398                 &cpu_tuple_cost,
2399                 DEFAULT_CPU_TUPLE_COST, 0, DBL_MAX,
2400                 NULL, NULL, NULL
2401         },
2402         {
2403                 {"cpu_index_tuple_cost", PGC_USERSET, QUERY_TUNING_COST,
2404                         gettext_noop("Sets the planner's estimate of the cost of "
2405                                                  "processing each index entry during an index scan."),
2406                         NULL
2407                 },
2408                 &cpu_index_tuple_cost,
2409                 DEFAULT_CPU_INDEX_TUPLE_COST, 0, DBL_MAX,
2410                 NULL, NULL, NULL
2411         },
2412         {
2413                 {"cpu_operator_cost", PGC_USERSET, QUERY_TUNING_COST,
2414                         gettext_noop("Sets the planner's estimate of the cost of "
2415                                                  "processing each operator or function call."),
2416                         NULL
2417                 },
2418                 &cpu_operator_cost,
2419                 DEFAULT_CPU_OPERATOR_COST, 0, DBL_MAX,
2420                 NULL, NULL, NULL
2421         },
2422
2423         {
2424                 {"cursor_tuple_fraction", PGC_USERSET, QUERY_TUNING_OTHER,
2425                         gettext_noop("Sets the planner's estimate of the fraction of "
2426                                                  "a cursor's rows that will be retrieved."),
2427                         NULL
2428                 },
2429                 &cursor_tuple_fraction,
2430                 DEFAULT_CURSOR_TUPLE_FRACTION, 0.0, 1.0,
2431                 NULL, NULL, NULL
2432         },
2433
2434         {
2435                 {"geqo_selection_bias", PGC_USERSET, QUERY_TUNING_GEQO,
2436                         gettext_noop("GEQO: selective pressure within the population."),
2437                         NULL
2438                 },
2439                 &Geqo_selection_bias,
2440                 DEFAULT_GEQO_SELECTION_BIAS,
2441                 MIN_GEQO_SELECTION_BIAS, MAX_GEQO_SELECTION_BIAS,
2442                 NULL, NULL, NULL
2443         },
2444         {
2445                 {"geqo_seed", PGC_USERSET, QUERY_TUNING_GEQO,
2446                         gettext_noop("GEQO: seed for random path selection."),
2447                         NULL
2448                 },
2449                 &Geqo_seed,
2450                 0.0, 0.0, 1.0,
2451                 NULL, NULL, NULL
2452         },
2453
2454         {
2455                 {"bgwriter_lru_multiplier", PGC_SIGHUP, RESOURCES_BGWRITER,
2456                         gettext_noop("Multiple of the average buffer usage to free per round."),
2457                         NULL
2458                 },
2459                 &bgwriter_lru_multiplier,
2460                 2.0, 0.0, 10.0,
2461                 NULL, NULL, NULL
2462         },
2463
2464         {
2465                 {"seed", PGC_USERSET, UNGROUPED,
2466                         gettext_noop("Sets the seed for random-number generation."),
2467                         NULL,
2468                         GUC_NO_SHOW_ALL | GUC_NO_RESET_ALL | GUC_NOT_IN_SAMPLE | GUC_DISALLOW_IN_FILE
2469                 },
2470                 &phony_random_seed,
2471                 0.0, -1.0, 1.0,
2472                 check_random_seed, assign_random_seed, show_random_seed
2473         },
2474
2475         {
2476                 {"autovacuum_vacuum_scale_factor", PGC_SIGHUP, AUTOVACUUM,
2477                         gettext_noop("Number of tuple updates or deletes prior to vacuum as a fraction of reltuples."),
2478                         NULL
2479                 },
2480                 &autovacuum_vac_scale,
2481                 0.2, 0.0, 100.0,
2482                 NULL, NULL, NULL
2483         },
2484         {
2485                 {"autovacuum_analyze_scale_factor", PGC_SIGHUP, AUTOVACUUM,
2486                         gettext_noop("Number of tuple inserts, updates or deletes prior to analyze as a fraction of reltuples."),
2487                         NULL
2488                 },
2489                 &autovacuum_anl_scale,
2490                 0.1, 0.0, 100.0,
2491                 NULL, NULL, NULL
2492         },
2493
2494         {
2495                 {"checkpoint_completion_target", PGC_SIGHUP, WAL_CHECKPOINTS,
2496                         gettext_noop("Time spent flushing dirty buffers during checkpoint, as fraction of checkpoint interval."),
2497                         NULL
2498                 },
2499                 &CheckPointCompletionTarget,
2500                 0.5, 0.0, 1.0,
2501                 NULL, NULL, NULL
2502         },
2503
2504         /* End-of-list marker */
2505         {
2506                 {NULL, 0, 0, NULL, NULL}, NULL, 0.0, 0.0, 0.0, NULL, NULL, NULL
2507         }
2508 };
2509
2510
2511 static struct config_string ConfigureNamesString[] =
2512 {
2513         {
2514                 {"archive_command", PGC_SIGHUP, WAL_ARCHIVING,
2515                         gettext_noop("Sets the shell command that will be called to archive a WAL file."),
2516                         NULL
2517                 },
2518                 &XLogArchiveCommand,
2519                 "",
2520                 NULL, NULL, show_archive_command
2521         },
2522
2523         {
2524                 {"client_encoding", PGC_USERSET, CLIENT_CONN_LOCALE,
2525                         gettext_noop("Sets the client's character set encoding."),
2526                         NULL,
2527                         GUC_IS_NAME | GUC_REPORT
2528                 },
2529                 &client_encoding_string,
2530                 "SQL_ASCII",
2531                 check_client_encoding, assign_client_encoding, NULL
2532         },
2533
2534         {
2535                 {"log_line_prefix", PGC_SIGHUP, LOGGING_WHAT,
2536                         gettext_noop("Controls information prefixed to each log line."),
2537                         gettext_noop("If blank, no prefix is used.")
2538                 },
2539                 &Log_line_prefix,
2540                 "",
2541                 NULL, NULL, NULL
2542         },
2543
2544         {
2545                 {"log_timezone", PGC_SIGHUP, LOGGING_WHAT,
2546                         gettext_noop("Sets the time zone to use in log messages."),
2547                         NULL
2548                 },
2549                 &log_timezone_string,
2550                 "GMT",
2551                 check_log_timezone, assign_log_timezone, show_log_timezone
2552         },
2553
2554         {
2555                 {"DateStyle", PGC_USERSET, CLIENT_CONN_LOCALE,
2556                         gettext_noop("Sets the display format for date and time values."),
2557                         gettext_noop("Also controls interpretation of ambiguous "
2558                                                  "date inputs."),
2559                         GUC_LIST_INPUT | GUC_REPORT
2560                 },
2561                 &datestyle_string,
2562                 "ISO, MDY",
2563                 check_datestyle, assign_datestyle, NULL
2564         },
2565
2566         {
2567                 {"default_tablespace", PGC_USERSET, CLIENT_CONN_STATEMENT,
2568                         gettext_noop("Sets the default tablespace to create tables and indexes in."),
2569                         gettext_noop("An empty string selects the database's default tablespace."),
2570                         GUC_IS_NAME
2571                 },
2572                 &default_tablespace,
2573                 "",
2574                 check_default_tablespace, NULL, NULL
2575         },
2576
2577         {
2578                 {"temp_tablespaces", PGC_USERSET, CLIENT_CONN_STATEMENT,
2579                         gettext_noop("Sets the tablespace(s) to use for temporary tables and sort files."),
2580                         NULL,
2581                         GUC_LIST_INPUT | GUC_LIST_QUOTE
2582                 },
2583                 &temp_tablespaces,
2584                 "",
2585                 check_temp_tablespaces, assign_temp_tablespaces, NULL
2586         },
2587
2588         {
2589                 {"dynamic_library_path", PGC_SUSET, CLIENT_CONN_OTHER,
2590                         gettext_noop("Sets the path for dynamically loadable modules."),
2591                         gettext_noop("If a dynamically loadable module needs to be opened and "
2592                                                  "the specified name does not have a directory component (i.e., the "
2593                                                  "name does not contain a slash), the system will search this path for "
2594                                                  "the specified file."),
2595                         GUC_SUPERUSER_ONLY
2596                 },
2597                 &Dynamic_library_path,
2598                 "$libdir",
2599                 NULL, NULL, NULL
2600         },
2601
2602         {
2603                 {"krb_server_keyfile", PGC_SIGHUP, CONN_AUTH_SECURITY,
2604                         gettext_noop("Sets the location of the Kerberos server key file."),
2605                         NULL,
2606                         GUC_SUPERUSER_ONLY
2607                 },
2608                 &pg_krb_server_keyfile,
2609                 PG_KRB_SRVTAB,
2610                 NULL, NULL, NULL
2611         },
2612
2613         {
2614                 {"krb_srvname", PGC_SIGHUP, CONN_AUTH_SECURITY,
2615                         gettext_noop("Sets the name of the Kerberos service."),
2616                         NULL
2617                 },
2618                 &pg_krb_srvnam,
2619                 PG_KRB_SRVNAM,
2620                 NULL, NULL, NULL
2621         },
2622
2623         {
2624                 {"bonjour_name", PGC_POSTMASTER, CONN_AUTH_SETTINGS,
2625                         gettext_noop("Sets the Bonjour service name."),
2626                         NULL
2627                 },
2628                 &bonjour_name,
2629                 "",
2630                 NULL, NULL, NULL
2631         },
2632
2633         /* See main.c about why defaults for LC_foo are not all alike */
2634
2635         {
2636                 {"lc_collate", PGC_INTERNAL, CLIENT_CONN_LOCALE,
2637                         gettext_noop("Shows the collation order locale."),
2638                         NULL,
2639                         GUC_NOT_IN_SAMPLE | GUC_DISALLOW_IN_FILE
2640                 },
2641                 &locale_collate,
2642                 "C",
2643                 NULL, NULL, NULL
2644         },
2645
2646         {
2647                 {"lc_ctype", PGC_INTERNAL, CLIENT_CONN_LOCALE,
2648                         gettext_noop("Shows the character classification and case conversion locale."),
2649                         NULL,
2650                         GUC_NOT_IN_SAMPLE | GUC_DISALLOW_IN_FILE
2651                 },
2652                 &locale_ctype,
2653                 "C",
2654                 NULL, NULL, NULL
2655         },
2656
2657         {
2658                 {"lc_messages", PGC_SUSET, CLIENT_CONN_LOCALE,
2659                         gettext_noop("Sets the language in which messages are displayed."),
2660                         NULL
2661                 },
2662                 &locale_messages,
2663                 "",
2664                 check_locale_messages, assign_locale_messages, NULL
2665         },
2666
2667         {
2668                 {"lc_monetary", PGC_USERSET, CLIENT_CONN_LOCALE,
2669                         gettext_noop("Sets the locale for formatting monetary amounts."),
2670                         NULL
2671                 },
2672                 &locale_monetary,
2673                 "C",
2674                 check_locale_monetary, assign_locale_monetary, NULL
2675         },
2676
2677         {
2678                 {"lc_numeric", PGC_USERSET, CLIENT_CONN_LOCALE,
2679                         gettext_noop("Sets the locale for formatting numbers."),
2680                         NULL
2681                 },
2682                 &locale_numeric,
2683                 "C",
2684                 check_locale_numeric, assign_locale_numeric, NULL
2685         },
2686
2687         {
2688                 {"lc_time", PGC_USERSET, CLIENT_CONN_LOCALE,
2689                         gettext_noop("Sets the locale for formatting date and time values."),
2690                         NULL
2691                 },
2692                 &locale_time,
2693                 "C",
2694                 check_locale_time, assign_locale_time, NULL
2695         },
2696
2697         {
2698                 {"shared_preload_libraries", PGC_POSTMASTER, RESOURCES_KERNEL,
2699                         gettext_noop("Lists shared libraries to preload into server."),
2700                         NULL,
2701                         GUC_LIST_INPUT | GUC_LIST_QUOTE | GUC_SUPERUSER_ONLY
2702                 },
2703                 &shared_preload_libraries_string,
2704                 "",
2705                 NULL, NULL, NULL
2706         },
2707
2708         {
2709                 {"local_preload_libraries", PGC_BACKEND, CLIENT_CONN_OTHER,
2710                         gettext_noop("Lists shared libraries to preload into each backend."),
2711                         NULL,
2712                         GUC_LIST_INPUT | GUC_LIST_QUOTE
2713                 },
2714                 &local_preload_libraries_string,
2715                 "",
2716                 NULL, NULL, NULL
2717         },
2718
2719         {
2720                 {"search_path", PGC_USERSET, CLIENT_CONN_STATEMENT,
2721                         gettext_noop("Sets the schema search order for names that are not schema-qualified."),
2722                         NULL,
2723                         GUC_LIST_INPUT | GUC_LIST_QUOTE
2724                 },
2725                 &namespace_search_path,
2726                 "\"$user\",public",
2727                 check_search_path, assign_search_path, NULL
2728         },
2729
2730         {
2731                 /* Can't be set in postgresql.conf */
2732                 {"server_encoding", PGC_INTERNAL, CLIENT_CONN_LOCALE,
2733                         gettext_noop("Sets the server (database) character set encoding."),
2734                         NULL,
2735                         GUC_IS_NAME | GUC_REPORT | GUC_NOT_IN_SAMPLE | GUC_DISALLOW_IN_FILE
2736                 },
2737                 &server_encoding_string,
2738                 "SQL_ASCII",
2739                 NULL, NULL, NULL
2740         },
2741
2742         {
2743                 /* Can't be set in postgresql.conf */
2744                 {"server_version", PGC_INTERNAL, PRESET_OPTIONS,
2745                         gettext_noop("Shows the server version."),
2746                         NULL,
2747                         GUC_REPORT | GUC_NOT_IN_SAMPLE | GUC_DISALLOW_IN_FILE
2748                 },
2749                 &server_version_string,
2750                 PG_VERSION,
2751                 NULL, NULL, NULL
2752         },
2753
2754         {
2755                 /* Not for general use --- used by SET ROLE */
2756                 {"role", PGC_USERSET, UNGROUPED,
2757                         gettext_noop("Sets the current role."),
2758                         NULL,
2759                         GUC_IS_NAME | GUC_NO_SHOW_ALL | GUC_NO_RESET_ALL | GUC_NOT_IN_SAMPLE | GUC_DISALLOW_IN_FILE | GUC_NOT_WHILE_SEC_REST
2760                 },
2761                 &role_string,
2762                 "none",
2763                 check_role, assign_role, show_role
2764         },
2765
2766         {
2767                 /* Not for general use --- used by SET SESSION AUTHORIZATION */
2768                 {"session_authorization", PGC_USERSET, UNGROUPED,
2769                         gettext_noop("Sets the session user name."),
2770                         NULL,
2771                         GUC_IS_NAME | GUC_REPORT | GUC_NO_SHOW_ALL | GUC_NO_RESET_ALL | GUC_NOT_IN_SAMPLE | GUC_DISALLOW_IN_FILE | GUC_NOT_WHILE_SEC_REST
2772                 },
2773                 &session_authorization_string,
2774                 NULL,
2775                 check_session_authorization, assign_session_authorization, NULL
2776         },
2777
2778         {
2779                 {"log_destination", PGC_SIGHUP, LOGGING_WHERE,
2780                         gettext_noop("Sets the destination for server log output."),
2781                         gettext_noop("Valid values are combinations of \"stderr\", "
2782                                                  "\"syslog\", \"csvlog\", and \"eventlog\", "
2783                                                  "depending on the platform."),
2784                         GUC_LIST_INPUT
2785                 },
2786                 &log_destination_string,
2787                 "stderr",
2788                 check_log_destination, assign_log_destination, NULL
2789         },
2790         {
2791                 {"log_directory", PGC_SIGHUP, LOGGING_WHERE,
2792                         gettext_noop("Sets the destination directory for log files."),
2793                         gettext_noop("Can be specified as relative to the data directory "
2794                                                  "or as absolute path."),
2795                         GUC_SUPERUSER_ONLY
2796                 },
2797                 &Log_directory,
2798                 "pg_log",
2799                 check_canonical_path, NULL, NULL
2800         },
2801         {
2802                 {"log_filename", PGC_SIGHUP, LOGGING_WHERE,
2803                         gettext_noop("Sets the file name pattern for log files."),
2804                         NULL,
2805                         GUC_SUPERUSER_ONLY
2806                 },
2807                 &Log_filename,
2808                 "postgresql-%Y-%m-%d_%H%M%S.log",
2809                 NULL, NULL, NULL
2810         },
2811
2812         {
2813                 {"syslog_ident", PGC_SIGHUP, LOGGING_WHERE,
2814                         gettext_noop("Sets the program name used to identify PostgreSQL "
2815                                                  "messages in syslog."),
2816                         NULL
2817                 },
2818                 &syslog_ident_str,
2819                 "postgres",
2820                 NULL, assign_syslog_ident, NULL
2821         },
2822
2823         {
2824                 {"event_source", PGC_POSTMASTER, LOGGING_WHERE,
2825                         gettext_noop("Sets the application name used to identify"
2826                                                  "PostgreSQL messages in the event log."),
2827                         NULL
2828                 },
2829                 &event_source,
2830                 "PostgreSQL",
2831                 NULL, NULL, NULL
2832         },
2833
2834         {
2835                 {"TimeZone", PGC_USERSET, CLIENT_CONN_LOCALE,
2836                         gettext_noop("Sets the time zone for displaying and interpreting time stamps."),
2837                         NULL,
2838                         GUC_REPORT
2839                 },
2840                 &timezone_string,
2841                 "GMT",
2842                 check_timezone, assign_timezone, show_timezone
2843         },
2844         {
2845                 {"timezone_abbreviations", PGC_USERSET, CLIENT_CONN_LOCALE,
2846                         gettext_noop("Selects a file of time zone abbreviations."),
2847                         NULL
2848                 },
2849                 &timezone_abbreviations_string,
2850                 NULL,
2851                 check_timezone_abbreviations, assign_timezone_abbreviations, NULL
2852         },
2853
2854         {
2855                 {"transaction_isolation", PGC_USERSET, CLIENT_CONN_STATEMENT,
2856                         gettext_noop("Sets the current transaction's isolation level."),
2857                         NULL,
2858                         GUC_NO_RESET_ALL | GUC_NOT_IN_SAMPLE | GUC_DISALLOW_IN_FILE
2859                 },
2860                 &XactIsoLevel_string,
2861                 "default",
2862                 check_XactIsoLevel, assign_XactIsoLevel, show_XactIsoLevel
2863         },
2864
2865         {
2866                 {"unix_socket_group", PGC_POSTMASTER, CONN_AUTH_SETTINGS,
2867                         gettext_noop("Sets the owning group of the Unix-domain socket."),
2868                         gettext_noop("The owning user of the socket is always the user "
2869                                                  "that starts the server.")
2870                 },
2871                 &Unix_socket_group,
2872                 "",
2873                 NULL, NULL, NULL
2874         },
2875
2876         {
2877                 {"unix_socket_directory", PGC_POSTMASTER, CONN_AUTH_SETTINGS,
2878                         gettext_noop("Sets the directory where the Unix-domain socket will be created."),
2879                         NULL,
2880                         GUC_SUPERUSER_ONLY
2881                 },
2882                 &UnixSocketDir,
2883                 "",
2884                 check_canonical_path, NULL, NULL
2885         },
2886
2887         {
2888                 {"listen_addresses", PGC_POSTMASTER, CONN_AUTH_SETTINGS,
2889                         gettext_noop("Sets the host name or IP address(es) to listen to."),
2890                         NULL,
2891                         GUC_LIST_INPUT
2892                 },
2893                 &ListenAddresses,
2894                 "localhost",
2895                 NULL, NULL, NULL
2896         },
2897
2898         {
2899                 {"data_directory", PGC_POSTMASTER, FILE_LOCATIONS,
2900                         gettext_noop("Sets the server's data directory."),
2901                         NULL,
2902                         GUC_SUPERUSER_ONLY
2903                 },
2904                 &data_directory,
2905                 NULL,
2906                 NULL, NULL, NULL
2907         },
2908
2909         {
2910                 {"config_file", PGC_POSTMASTER, FILE_LOCATIONS,
2911                         gettext_noop("Sets the server's main configuration file."),
2912                         NULL,
2913                         GUC_DISALLOW_IN_FILE | GUC_SUPERUSER_ONLY
2914                 },
2915                 &ConfigFileName,
2916                 NULL,
2917                 NULL, NULL, NULL
2918         },
2919
2920         {
2921                 {"hba_file", PGC_POSTMASTER, FILE_LOCATIONS,
2922                         gettext_noop("Sets the server's \"hba\" configuration file."),
2923                         NULL,
2924                         GUC_SUPERUSER_ONLY
2925                 },
2926                 &HbaFileName,
2927                 NULL,
2928                 NULL, NULL, NULL
2929         },
2930
2931         {
2932                 {"ident_file", PGC_POSTMASTER, FILE_LOCATIONS,
2933                         gettext_noop("Sets the server's \"ident\" configuration file."),
2934                         NULL,
2935                         GUC_SUPERUSER_ONLY
2936                 },
2937                 &IdentFileName,
2938                 NULL,
2939                 NULL, NULL, NULL
2940         },
2941
2942         {
2943                 {"external_pid_file", PGC_POSTMASTER, FILE_LOCATIONS,
2944                         gettext_noop("Writes the postmaster PID to the specified file."),
2945                         NULL,
2946                         GUC_SUPERUSER_ONLY
2947                 },
2948                 &external_pid_file,
2949                 NULL,
2950                 check_canonical_path, NULL, NULL
2951         },
2952
2953         {
2954                 {"stats_temp_directory", PGC_SIGHUP, STATS_COLLECTOR,
2955                         gettext_noop("Writes temporary statistics files to the specified directory."),
2956                         NULL,
2957                         GUC_SUPERUSER_ONLY
2958                 },
2959                 &pgstat_temp_directory,
2960                 "pg_stat_tmp",
2961                 check_canonical_path, assign_pgstat_temp_directory, NULL
2962         },
2963
2964         {
2965                 {"synchronous_standby_names", PGC_SIGHUP, REPLICATION_MASTER,
2966                         gettext_noop("List of names of potential synchronous standbys."),
2967                         NULL,
2968                         GUC_LIST_INPUT
2969                 },
2970                 &SyncRepStandbyNames,
2971                 "",
2972                 check_synchronous_standby_names, NULL, NULL
2973         },
2974
2975         {
2976                 {"default_text_search_config", PGC_USERSET, CLIENT_CONN_LOCALE,
2977                         gettext_noop("Sets default text search configuration."),
2978                         NULL
2979                 },
2980                 &TSCurrentConfig,
2981                 "pg_catalog.simple",
2982                 check_TSCurrentConfig, assign_TSCurrentConfig, NULL
2983         },
2984
2985         {
2986                 {"ssl_ciphers", PGC_POSTMASTER, CONN_AUTH_SECURITY,
2987                         gettext_noop("Sets the list of allowed SSL ciphers."),
2988                         NULL,
2989                         GUC_SUPERUSER_ONLY
2990                 },
2991                 &SSLCipherSuites,
2992 #ifdef USE_SSL
2993                 "ALL:!ADH:!LOW:!EXP:!MD5:@STRENGTH",
2994 #else
2995                 "none",
2996 #endif
2997                 NULL, NULL, NULL
2998         },
2999
3000         {
3001                 {"application_name", PGC_USERSET, LOGGING_WHAT,
3002                         gettext_noop("Sets the application name to be reported in statistics and logs."),
3003                         NULL,
3004                         GUC_IS_NAME | GUC_REPORT | GUC_NOT_IN_SAMPLE
3005                 },
3006                 &application_name,
3007                 "",
3008                 check_application_name, assign_application_name, NULL
3009         },
3010
3011         /* End-of-list marker */
3012         {
3013                 {NULL, 0, 0, NULL, NULL}, NULL, NULL, NULL, NULL, NULL
3014         }
3015 };
3016
3017
3018 static struct config_enum ConfigureNamesEnum[] =
3019 {
3020         {
3021                 {"backslash_quote", PGC_USERSET, COMPAT_OPTIONS_PREVIOUS,
3022                         gettext_noop("Sets whether \"\\'\" is allowed in string literals."),
3023                         NULL
3024                 },
3025                 &backslash_quote,
3026                 BACKSLASH_QUOTE_SAFE_ENCODING, backslash_quote_options,
3027                 NULL, NULL, NULL
3028         },
3029
3030         {
3031                 {"bytea_output", PGC_USERSET, CLIENT_CONN_STATEMENT,
3032                         gettext_noop("Sets the output format for bytea."),
3033                         NULL
3034                 },
3035                 &bytea_output,
3036                 BYTEA_OUTPUT_HEX, bytea_output_options,
3037                 NULL, NULL, NULL
3038         },
3039
3040         {
3041                 {"client_min_messages", PGC_USERSET, LOGGING_WHEN,
3042                         gettext_noop("Sets the message levels that are sent to the client."),
3043                         gettext_noop("Each level includes all the levels that follow it. The later"
3044                                                  " the level, the fewer messages are sent.")
3045                 },
3046                 &client_min_messages,
3047                 NOTICE, client_message_level_options,
3048                 NULL, NULL, NULL
3049         },
3050
3051         {
3052                 {"constraint_exclusion", PGC_USERSET, QUERY_TUNING_OTHER,
3053                         gettext_noop("Enables the planner to use constraints to optimize queries."),
3054                         gettext_noop("Table scans will be skipped if their constraints"
3055                                                  " guarantee that no rows match the query.")
3056                 },
3057                 &constraint_exclusion,
3058                 CONSTRAINT_EXCLUSION_PARTITION, constraint_exclusion_options,
3059                 NULL, NULL, NULL
3060         },
3061
3062         {
3063                 {"default_transaction_isolation", PGC_USERSET, CLIENT_CONN_STATEMENT,
3064                         gettext_noop("Sets the transaction isolation level of each new transaction."),
3065                         NULL
3066                 },
3067                 &DefaultXactIsoLevel,
3068                 XACT_READ_COMMITTED, isolation_level_options,
3069                 NULL, NULL, NULL
3070         },
3071
3072         {
3073                 {"IntervalStyle", PGC_USERSET, CLIENT_CONN_LOCALE,
3074                         gettext_noop("Sets the display format for interval values."),
3075                         NULL,
3076                         GUC_REPORT
3077                 },
3078                 &IntervalStyle,
3079                 INTSTYLE_POSTGRES, intervalstyle_options,
3080                 NULL, NULL, NULL
3081         },
3082
3083         {
3084                 {"log_error_verbosity", PGC_SUSET, LOGGING_WHAT,
3085                         gettext_noop("Sets the verbosity of logged messages."),
3086                         NULL
3087                 },
3088                 &Log_error_verbosity,
3089                 PGERROR_DEFAULT, log_error_verbosity_options,
3090                 NULL, NULL, NULL
3091         },
3092
3093         {
3094                 {"log_min_messages", PGC_SUSET, LOGGING_WHEN,
3095                         gettext_noop("Sets the message levels that are logged."),
3096                         gettext_noop("Each level includes all the levels that follow it. The later"
3097                                                  " the level, the fewer messages are sent.")
3098                 },
3099                 &log_min_messages,
3100                 WARNING, server_message_level_options,
3101                 NULL, NULL, NULL
3102         },
3103
3104         {
3105                 {"log_min_error_statement", PGC_SUSET, LOGGING_WHEN,
3106                         gettext_noop("Causes all statements generating error at or above this level to be logged."),
3107                         gettext_noop("Each level includes all the levels that follow it. The later"
3108                                                  " the level, the fewer messages are sent.")
3109                 },
3110                 &log_min_error_statement,
3111                 ERROR, server_message_level_options,
3112                 NULL, NULL, NULL
3113         },
3114
3115         {
3116                 {"log_statement", PGC_SUSET, LOGGING_WHAT,
3117                         gettext_noop("Sets the type of statements logged."),
3118                         NULL
3119                 },
3120                 &log_statement,
3121                 LOGSTMT_NONE, log_statement_options,
3122                 NULL, NULL, NULL
3123         },
3124
3125         {
3126                 {"syslog_facility", PGC_SIGHUP, LOGGING_WHERE,
3127                         gettext_noop("Sets the syslog \"facility\" to be used when syslog enabled."),
3128                         NULL
3129                 },
3130                 &syslog_facility,
3131 #ifdef HAVE_SYSLOG
3132                 LOG_LOCAL0,
3133 #else
3134                 0,
3135 #endif
3136                 syslog_facility_options,
3137                 NULL, assign_syslog_facility, NULL
3138         },
3139
3140         {
3141                 {"session_replication_role", PGC_SUSET, CLIENT_CONN_STATEMENT,
3142                         gettext_noop("Sets the session's behavior for triggers and rewrite rules."),
3143                         NULL
3144                 },
3145                 &SessionReplicationRole,
3146                 SESSION_REPLICATION_ROLE_ORIGIN, session_replication_role_options,
3147                 NULL, assign_session_replication_role, NULL
3148         },
3149
3150         {
3151                 {"synchronous_commit", PGC_USERSET, WAL_SETTINGS,
3152                         gettext_noop("Sets the current transaction's synchronization level."),
3153                         NULL
3154                 },
3155                 &synchronous_commit,
3156                 SYNCHRONOUS_COMMIT_ON, synchronous_commit_options,
3157                 NULL, NULL, NULL
3158         },
3159
3160         {
3161                 {"trace_recovery_messages", PGC_SIGHUP, DEVELOPER_OPTIONS,
3162                         gettext_noop("Enables logging of recovery-related debugging information."),
3163                         gettext_noop("Each level includes all the levels that follow it. The later"
3164                                                  " the level, the fewer messages are sent.")
3165                 },
3166                 &trace_recovery_messages,
3167
3168                 /*
3169                  * client_message_level_options allows too many values, really, but
3170                  * it's not worth having a separate options array for this.
3171                  */
3172                 LOG, client_message_level_options,
3173                 NULL, NULL, NULL
3174         },
3175
3176         {
3177                 {"track_functions", PGC_SUSET, STATS_COLLECTOR,
3178                         gettext_noop("Collects function-level statistics on database activity."),
3179                         NULL
3180                 },
3181                 &pgstat_track_functions,
3182                 TRACK_FUNC_OFF, track_function_options,
3183                 NULL, NULL, NULL
3184         },
3185
3186         {
3187                 {"wal_level", PGC_POSTMASTER, WAL_SETTINGS,
3188                         gettext_noop("Set the level of information written to the WAL."),
3189                         NULL
3190                 },
3191                 &wal_level,
3192                 WAL_LEVEL_MINIMAL, wal_level_options,
3193                 NULL, NULL, NULL
3194         },
3195
3196         {
3197                 {"wal_sync_method", PGC_SIGHUP, WAL_SETTINGS,
3198                         gettext_noop("Selects the method used for forcing WAL updates to disk."),
3199                         NULL
3200                 },
3201                 &sync_method,
3202                 DEFAULT_SYNC_METHOD, sync_method_options,
3203                 NULL, assign_xlog_sync_method, NULL
3204         },
3205
3206         {
3207                 {"xmlbinary", PGC_USERSET, CLIENT_CONN_STATEMENT,
3208                         gettext_noop("Sets how binary values are to be encoded in XML."),
3209                         NULL
3210                 },
3211                 &xmlbinary,
3212                 XMLBINARY_BASE64, xmlbinary_options,
3213                 NULL, NULL, NULL
3214         },
3215
3216         {
3217                 {"xmloption", PGC_USERSET, CLIENT_CONN_STATEMENT,
3218                         gettext_noop("Sets whether XML data in implicit parsing and serialization "
3219                                                  "operations is to be considered as documents or content fragments."),
3220                         NULL
3221                 },
3222                 &xmloption,
3223                 XMLOPTION_CONTENT, xmloption_options,
3224                 NULL, NULL, NULL
3225         },
3226
3227
3228         /* End-of-list marker */
3229         {
3230                 {NULL, 0, 0, NULL, NULL}, NULL, 0, NULL, NULL, NULL, NULL
3231         }
3232 };
3233
3234 /******** end of options list ********/
3235
3236
3237 /*
3238  * To allow continued support of obsolete names for GUC variables, we apply
3239  * the following mappings to any unrecognized name.  Note that an old name
3240  * should be mapped to a new one only if the new variable has very similar
3241  * semantics to the old.
3242  */
3243 static const char *const map_old_guc_names[] = {
3244         "sort_mem", "work_mem",
3245         "vacuum_mem", "maintenance_work_mem",
3246         NULL
3247 };
3248
3249
3250 /*
3251  * Actual lookup of variables is done through this single, sorted array.
3252  */
3253 static struct config_generic **guc_variables;
3254
3255 /* Current number of variables contained in the vector */
3256 static int      num_guc_variables;
3257
3258 /* Vector capacity */
3259 static int      size_guc_variables;
3260
3261
3262 static bool guc_dirty;                  /* TRUE if need to do commit/abort work */
3263
3264 static bool reporting_enabled;  /* TRUE to enable GUC_REPORT */
3265
3266 static int      GUCNestLevel = 0;       /* 1 when in main transaction */
3267
3268
3269 static int      guc_var_compare(const void *a, const void *b);
3270 static int      guc_name_compare(const char *namea, const char *nameb);
3271 static void InitializeGUCOptionsFromEnvironment(void);
3272 static void InitializeOneGUCOption(struct config_generic * gconf);
3273 static void push_old_value(struct config_generic * gconf, GucAction action);
3274 static void ReportGUCOption(struct config_generic * record);
3275 static void reapply_stacked_values(struct config_generic * variable,
3276                                            struct config_string *pHolder,
3277                                            GucStack *stack,
3278                                            const char *curvalue,
3279                                            GucContext curscontext, GucSource cursource);
3280 static void ShowGUCConfigOption(const char *name, DestReceiver *dest);
3281 static void ShowAllGUCConfig(DestReceiver *dest);
3282 static char *_ShowOption(struct config_generic * record, bool use_units);
3283 static bool validate_option_array_item(const char *name, const char *value,
3284                                                    bool skipIfNoPermissions);
3285
3286
3287 /*
3288  * Some infrastructure for checking malloc/strdup/realloc calls
3289  */
3290 static void *
3291 guc_malloc(int elevel, size_t size)
3292 {
3293         void       *data;
3294
3295         data = malloc(size);
3296         if (data == NULL)
3297                 ereport(elevel,
3298                                 (errcode(ERRCODE_OUT_OF_MEMORY),
3299                                  errmsg("out of memory")));
3300         return data;
3301 }
3302
3303 static void *
3304 guc_realloc(int elevel, void *old, size_t size)
3305 {
3306         void       *data;
3307
3308         data = realloc(old, size);
3309         if (data == NULL)
3310                 ereport(elevel,
3311                                 (errcode(ERRCODE_OUT_OF_MEMORY),
3312                                  errmsg("out of memory")));
3313         return data;
3314 }
3315
3316 static char *
3317 guc_strdup(int elevel, const char *src)
3318 {
3319         char       *data;
3320
3321         data = strdup(src);
3322         if (data == NULL)
3323                 ereport(elevel,
3324                                 (errcode(ERRCODE_OUT_OF_MEMORY),
3325                                  errmsg("out of memory")));
3326         return data;
3327 }
3328
3329
3330 /*
3331  * Detect whether strval is referenced anywhere in a GUC string item
3332  */
3333 static bool
3334 string_field_used(struct config_string * conf, char *strval)
3335 {
3336         GucStack   *stack;
3337
3338         if (strval == *(conf->variable) ||
3339                 strval == conf->reset_val ||
3340                 strval == conf->boot_val)
3341                 return true;
3342         for (stack = conf->gen.stack; stack; stack = stack->prev)
3343         {
3344                 if (strval == stack->prior.val.stringval ||
3345                         strval == stack->masked.val.stringval)
3346                         return true;
3347         }
3348         return false;
3349 }
3350
3351 /*
3352  * Support for assigning to a field of a string GUC item.  Free the prior
3353  * value if it's not referenced anywhere else in the item (including stacked
3354  * states).
3355  */
3356 static void
3357 set_string_field(struct config_string * conf, char **field, char *newval)
3358 {
3359         char       *oldval = *field;
3360
3361         /* Do the assignment */
3362         *field = newval;
3363
3364         /* Free old value if it's not NULL and isn't referenced anymore */
3365         if (oldval && !string_field_used(conf, oldval))
3366                 free(oldval);
3367 }
3368
3369 /*
3370  * Detect whether an "extra" struct is referenced anywhere in a GUC item
3371  */
3372 static bool
3373 extra_field_used(struct config_generic * gconf, void *extra)
3374 {
3375         GucStack   *stack;
3376
3377         if (extra == gconf->extra)
3378                 return true;
3379         switch (gconf->vartype)
3380         {
3381                 case PGC_BOOL:
3382                         if (extra == ((struct config_bool *) gconf)->reset_extra)
3383                                 return true;
3384                         break;
3385                 case PGC_INT:
3386                         if (extra == ((struct config_int *) gconf)->reset_extra)
3387                                 return true;
3388                         break;
3389                 case PGC_REAL:
3390                         if (extra == ((struct config_real *) gconf)->reset_extra)
3391                                 return true;
3392                         break;
3393                 case PGC_STRING:
3394                         if (extra == ((struct config_string *) gconf)->reset_extra)
3395                                 return true;
3396                         break;
3397                 case PGC_ENUM:
3398                         if (extra == ((struct config_enum *) gconf)->reset_extra)
3399                                 return true;
3400                         break;
3401         }
3402         for (stack = gconf->stack; stack; stack = stack->prev)
3403         {
3404                 if (extra == stack->prior.extra ||
3405                         extra == stack->masked.extra)
3406                         return true;
3407         }
3408
3409         return false;
3410 }
3411
3412 /*
3413  * Support for assigning to an "extra" field of a GUC item.  Free the prior
3414  * value if it's not referenced anywhere else in the item (including stacked
3415  * states).
3416  */
3417 static void
3418 set_extra_field(struct config_generic * gconf, void **field, void *newval)
3419 {
3420         void       *oldval = *field;
3421
3422         /* Do the assignment */
3423         *field = newval;
3424
3425         /* Free old value if it's not NULL and isn't referenced anymore */
3426         if (oldval && !extra_field_used(gconf, oldval))
3427                 free(oldval);
3428 }
3429
3430 /*
3431  * Support for copying a variable's active value into a stack entry.
3432  * The "extra" field associated with the active value is copied, too.
3433  *
3434  * NB: be sure stringval and extra fields of a new stack entry are
3435  * initialized to NULL before this is used, else we'll try to free() them.
3436  */
3437 static void
3438 set_stack_value(struct config_generic * gconf, config_var_value *val)
3439 {
3440         switch (gconf->vartype)
3441         {
3442                 case PGC_BOOL:
3443                         val->val.boolval =
3444                                 *((struct config_bool *) gconf)->variable;
3445                         break;
3446                 case PGC_INT:
3447                         val->val.intval =
3448                                 *((struct config_int *) gconf)->variable;
3449                         break;
3450                 case PGC_REAL:
3451                         val->val.realval =
3452                                 *((struct config_real *) gconf)->variable;
3453                         break;
3454                 case PGC_STRING:
3455                         set_string_field((struct config_string *) gconf,
3456                                                          &(val->val.stringval),
3457                                                          *((struct config_string *) gconf)->variable);
3458                         break;
3459                 case PGC_ENUM:
3460                         val->val.enumval =
3461                                 *((struct config_enum *) gconf)->variable;
3462                         break;
3463         }
3464         set_extra_field(gconf, &(val->extra), gconf->extra);
3465 }
3466
3467 /*
3468  * Support for discarding a no-longer-needed value in a stack entry.
3469  * The "extra" field associated with the stack entry is cleared, too.
3470  */
3471 static void
3472 discard_stack_value(struct config_generic * gconf, config_var_value *val)
3473 {
3474         switch (gconf->vartype)
3475         {
3476                 case PGC_BOOL:
3477                 case PGC_INT:
3478                 case PGC_REAL:
3479                 case PGC_ENUM:
3480                         /* no need to do anything */
3481                         break;
3482                 case PGC_STRING:
3483                         set_string_field((struct config_string *) gconf,
3484                                                          &(val->val.stringval),
3485                                                          NULL);
3486                         break;
3487         }
3488         set_extra_field(gconf, &(val->extra), NULL);
3489 }
3490
3491
3492 /*
3493  * Fetch the sorted array pointer (exported for help_config.c's use ONLY)
3494  */
3495 struct config_generic **
3496 get_guc_variables(void)
3497 {
3498         return guc_variables;
3499 }
3500
3501
3502 /*
3503  * Build the sorted array.      This is split out so that it could be
3504  * re-executed after startup (eg, we could allow loadable modules to
3505  * add vars, and then we'd need to re-sort).
3506  */
3507 void
3508 build_guc_variables(void)
3509 {
3510         int                     size_vars;
3511         int                     num_vars = 0;
3512         struct config_generic **guc_vars;
3513         int                     i;
3514
3515         for (i = 0; ConfigureNamesBool[i].gen.name; i++)
3516         {
3517                 struct config_bool *conf = &ConfigureNamesBool[i];
3518
3519                 /* Rather than requiring vartype to be filled in by hand, do this: */
3520                 conf->gen.vartype = PGC_BOOL;
3521                 num_vars++;
3522         }
3523
3524         for (i = 0; ConfigureNamesInt[i].gen.name; i++)
3525         {
3526                 struct config_int *conf = &ConfigureNamesInt[i];
3527
3528                 conf->gen.vartype = PGC_INT;
3529                 num_vars++;
3530         }
3531
3532         for (i = 0; ConfigureNamesReal[i].gen.name; i++)
3533         {
3534                 struct config_real *conf = &ConfigureNamesReal[i];
3535
3536                 conf->gen.vartype = PGC_REAL;
3537                 num_vars++;
3538         }
3539
3540         for (i = 0; ConfigureNamesString[i].gen.name; i++)
3541         {
3542                 struct config_string *conf = &ConfigureNamesString[i];
3543
3544                 conf->gen.vartype = PGC_STRING;
3545                 num_vars++;
3546         }
3547
3548         for (i = 0; ConfigureNamesEnum[i].gen.name; i++)
3549         {
3550                 struct config_enum *conf = &ConfigureNamesEnum[i];
3551
3552                 conf->gen.vartype = PGC_ENUM;
3553                 num_vars++;
3554         }
3555
3556         /*
3557          * Create table with 20% slack
3558          */
3559         size_vars = num_vars + num_vars / 4;
3560
3561         guc_vars = (struct config_generic **)
3562                 guc_malloc(FATAL, size_vars * sizeof(struct config_generic *));
3563
3564         num_vars = 0;
3565
3566         for (i = 0; ConfigureNamesBool[i].gen.name; i++)
3567                 guc_vars[num_vars++] = &ConfigureNamesBool[i].gen;
3568
3569         for (i = 0; ConfigureNamesInt[i].gen.name; i++)
3570                 guc_vars[num_vars++] = &ConfigureNamesInt[i].gen;
3571
3572         for (i = 0; ConfigureNamesReal[i].gen.name; i++)
3573                 guc_vars[num_vars++] = &ConfigureNamesReal[i].gen;
3574
3575         for (i = 0; ConfigureNamesString[i].gen.name; i++)
3576                 guc_vars[num_vars++] = &ConfigureNamesString[i].gen;
3577
3578         for (i = 0; ConfigureNamesEnum[i].gen.name; i++)
3579                 guc_vars[num_vars++] = &ConfigureNamesEnum[i].gen;
3580
3581         if (guc_variables)
3582                 free(guc_variables);
3583         guc_variables = guc_vars;
3584         num_guc_variables = num_vars;
3585         size_guc_variables = size_vars;
3586         qsort((void *) guc_variables, num_guc_variables,
3587                   sizeof(struct config_generic *), guc_var_compare);
3588 }
3589
3590 /*
3591  * Add a new GUC variable to the list of known variables. The
3592  * list is expanded if needed.
3593  */
3594 static bool
3595 add_guc_variable(struct config_generic * var, int elevel)
3596 {
3597         if (num_guc_variables + 1 >= size_guc_variables)
3598         {
3599                 /*
3600                  * Increase the vector by 25%
3601                  */
3602                 int                     size_vars = size_guc_variables + size_guc_variables / 4;
3603                 struct config_generic **guc_vars;
3604
3605                 if (size_vars == 0)
3606                 {
3607                         size_vars = 100;
3608                         guc_vars = (struct config_generic **)
3609                                 guc_malloc(elevel, size_vars * sizeof(struct config_generic *));
3610                 }
3611                 else
3612                 {
3613                         guc_vars = (struct config_generic **)
3614                                 guc_realloc(elevel, guc_variables, size_vars * sizeof(struct config_generic *));
3615                 }
3616
3617                 if (guc_vars == NULL)
3618                         return false;           /* out of memory */
3619
3620                 guc_variables = guc_vars;
3621                 size_guc_variables = size_vars;
3622         }
3623         guc_variables[num_guc_variables++] = var;
3624         qsort((void *) guc_variables, num_guc_variables,
3625                   sizeof(struct config_generic *), guc_var_compare);
3626         return true;
3627 }
3628
3629 /*
3630  * Create and add a placeholder variable for a custom variable name.
3631  */
3632 static struct config_generic *
3633 add_placeholder_variable(const char *name, int elevel)
3634 {
3635         size_t          sz = sizeof(struct config_string) + sizeof(char *);
3636         struct config_string *var;
3637         struct config_generic *gen;
3638
3639         var = (struct config_string *) guc_malloc(elevel, sz);
3640         if (var == NULL)
3641                 return NULL;
3642         memset(var, 0, sz);
3643         gen = &var->gen;
3644
3645         gen->name = guc_strdup(elevel, name);
3646         if (gen->name == NULL)
3647         {
3648                 free(var);
3649                 return NULL;
3650         }
3651
3652         gen->context = PGC_USERSET;
3653         gen->group = CUSTOM_OPTIONS;
3654         gen->short_desc = "GUC placeholder variable";
3655         gen->flags = GUC_NO_SHOW_ALL | GUC_NOT_IN_SAMPLE | GUC_CUSTOM_PLACEHOLDER;
3656         gen->vartype = PGC_STRING;
3657
3658         /*
3659          * The char* is allocated at the end of the struct since we have no
3660          * 'static' place to point to.  Note that the current value, as well as
3661          * the boot and reset values, start out NULL.
3662          */
3663         var->variable = (char **) (var + 1);
3664
3665         if (!add_guc_variable((struct config_generic *) var, elevel))
3666         {
3667                 free((void *) gen->name);
3668                 free(var);
3669                 return NULL;
3670         }
3671
3672         return gen;
3673 }
3674
3675 /*
3676  * Look up option NAME.  If it exists, return a pointer to its record,
3677  * else return NULL.  If create_placeholders is TRUE, we'll create a
3678  * placeholder record for a valid-looking custom variable name.
3679  */
3680 static struct config_generic *
3681 find_option(const char *name, bool create_placeholders, int elevel)
3682 {
3683         const char **key = &name;
3684         struct config_generic **res;
3685         int                     i;
3686
3687         Assert(name);
3688
3689         /*
3690          * By equating const char ** with struct config_generic *, we are assuming
3691          * the name field is first in config_generic.
3692          */
3693         res = (struct config_generic **) bsearch((void *) &key,
3694                                                                                          (void *) guc_variables,
3695                                                                                          num_guc_variables,
3696                                                                                          sizeof(struct config_generic *),
3697                                                                                          guc_var_compare);
3698         if (res)
3699                 return *res;
3700
3701         /*
3702          * See if the name is an obsolete name for a variable.  We assume that the
3703          * set of supported old names is short enough that a brute-force search is
3704          * the best way.
3705          */
3706         for (i = 0; map_old_guc_names[i] != NULL; i += 2)
3707         {
3708                 if (guc_name_compare(name, map_old_guc_names[i]) == 0)
3709                         return find_option(map_old_guc_names[i + 1], false, elevel);
3710         }
3711
3712         if (create_placeholders)
3713         {
3714                 /*
3715                  * Check if the name is qualified, and if so, add a placeholder.
3716                  */
3717                 if (strchr(name, GUC_QUALIFIER_SEPARATOR) != NULL)
3718                         return add_placeholder_variable(name, elevel);
3719         }
3720
3721         /* Unknown name */
3722         return NULL;
3723 }
3724
3725
3726 /*
3727  * comparator for qsorting and bsearching guc_variables array
3728  */
3729 static int
3730 guc_var_compare(const void *a, const void *b)
3731 {
3732         struct config_generic *confa = *(struct config_generic **) a;
3733         struct config_generic *confb = *(struct config_generic **) b;
3734
3735         return guc_name_compare(confa->name, confb->name);
3736 }
3737
3738 /*
3739  * the bare comparison function for GUC names
3740  */
3741 static int
3742 guc_name_compare(const char *namea, const char *nameb)
3743 {
3744         /*
3745          * The temptation to use strcasecmp() here must be resisted, because the
3746          * array ordering has to remain stable across setlocale() calls. So, build
3747          * our own with a simple ASCII-only downcasing.
3748          */
3749         while (*namea && *nameb)
3750         {
3751                 char            cha = *namea++;
3752                 char            chb = *nameb++;
3753
3754                 if (cha >= 'A' && cha <= 'Z')
3755                         cha += 'a' - 'A';
3756                 if (chb >= 'A' && chb <= 'Z')
3757                         chb += 'a' - 'A';
3758                 if (cha != chb)
3759                         return cha - chb;
3760         }
3761         if (*namea)
3762                 return 1;                               /* a is longer */
3763         if (*nameb)
3764                 return -1;                              /* b is longer */
3765         return 0;
3766 }
3767
3768
3769 /*
3770  * Initialize GUC options during program startup.
3771  *
3772  * Note that we cannot read the config file yet, since we have not yet
3773  * processed command-line switches.
3774  */
3775 void
3776 InitializeGUCOptions(void)
3777 {
3778         int                     i;
3779
3780         /*
3781          * Before log_line_prefix could possibly receive a nonempty setting, make
3782          * sure that timezone processing is minimally alive (see elog.c).
3783          */
3784         pg_timezone_initialize();
3785
3786         /*
3787          * Build sorted array of all GUC variables.
3788          */
3789         build_guc_variables();
3790
3791         /*
3792          * Load all variables with their compiled-in defaults, and initialize
3793          * status fields as needed.
3794          */
3795         for (i = 0; i < num_guc_variables; i++)
3796         {
3797                 InitializeOneGUCOption(guc_variables[i]);
3798         }
3799
3800         guc_dirty = false;
3801
3802         reporting_enabled = false;
3803
3804         /*
3805          * Prevent any attempt to override the transaction modes from
3806          * non-interactive sources.
3807          */
3808         SetConfigOption("transaction_isolation", "default",
3809                                         PGC_POSTMASTER, PGC_S_OVERRIDE);
3810         SetConfigOption("transaction_read_only", "no",
3811                                         PGC_POSTMASTER, PGC_S_OVERRIDE);
3812         SetConfigOption("transaction_deferrable", "no",
3813                                         PGC_POSTMASTER, PGC_S_OVERRIDE);
3814
3815         /*
3816          * For historical reasons, some GUC parameters can receive defaults from
3817          * environment variables.  Process those settings.
3818          */
3819         InitializeGUCOptionsFromEnvironment();
3820 }
3821
3822 /*
3823  * Assign any GUC values that can come from the server's environment.
3824  *
3825  * This is called from InitializeGUCOptions, and also from ProcessConfigFile
3826  * to deal with the possibility that a setting has been removed from
3827  * postgresql.conf and should now get a value from the environment.
3828  * (The latter is a kludge that should probably go away someday; if so,
3829  * fold this back into InitializeGUCOptions.)
3830  */
3831 static void
3832 InitializeGUCOptionsFromEnvironment(void)
3833 {
3834         char       *env;
3835         long            stack_rlimit;
3836
3837         env = getenv("PGPORT");
3838         if (env != NULL)
3839                 SetConfigOption("port", env, PGC_POSTMASTER, PGC_S_ENV_VAR);
3840
3841         env = getenv("PGDATESTYLE");
3842         if (env != NULL)
3843                 SetConfigOption("datestyle", env, PGC_POSTMASTER, PGC_S_ENV_VAR);
3844
3845         env = getenv("PGCLIENTENCODING");
3846         if (env != NULL)
3847                 SetConfigOption("client_encoding", env, PGC_POSTMASTER, PGC_S_ENV_VAR);
3848
3849         /*
3850          * rlimit isn't exactly an "environment variable", but it behaves about
3851          * the same.  If we can identify the platform stack depth rlimit, increase
3852          * default stack depth setting up to whatever is safe (but at most 2MB).
3853          */
3854         stack_rlimit = get_stack_depth_rlimit();
3855         if (stack_rlimit > 0)
3856         {
3857                 long            new_limit = (stack_rlimit - STACK_DEPTH_SLOP) / 1024L;
3858
3859                 if (new_limit > 100)
3860                 {
3861                         char            limbuf[16];
3862
3863                         new_limit = Min(new_limit, 2048);
3864                         sprintf(limbuf, "%ld", new_limit);
3865                         SetConfigOption("max_stack_depth", limbuf,
3866                                                         PGC_POSTMASTER, PGC_S_ENV_VAR);
3867                 }
3868         }
3869 }
3870
3871 /*
3872  * Initialize one GUC option variable to its compiled-in default.
3873  *
3874  * Note: the reason for calling check_hooks is not that we think the boot_val
3875  * might fail, but that the hooks might wish to compute an "extra" struct.
3876  */
3877 static void
3878 InitializeOneGUCOption(struct config_generic * gconf)
3879 {
3880         gconf->status = 0;
3881         gconf->source = PGC_S_DEFAULT;
3882         gconf->reset_source = PGC_S_DEFAULT;
3883         gconf->scontext = PGC_INTERNAL;
3884         gconf->reset_scontext = PGC_INTERNAL;
3885         gconf->stack = NULL;
3886         gconf->extra = NULL;
3887         gconf->sourcefile = NULL;
3888         gconf->sourceline = 0;
3889
3890         switch (gconf->vartype)
3891         {
3892                 case PGC_BOOL:
3893                         {
3894                                 struct config_bool *conf = (struct config_bool *) gconf;
3895                                 bool            newval = conf->boot_val;
3896                                 void       *extra = NULL;
3897
3898                                 if (!call_bool_check_hook(conf, &newval, &extra,
3899                                                                                   PGC_S_DEFAULT, LOG))
3900                                         elog(FATAL, "failed to initialize %s to %d",
3901                                                  conf->gen.name, (int) newval);
3902                                 if (conf->assign_hook)
3903                                         (*conf->assign_hook) (newval, extra);
3904                                 *conf->variable = conf->reset_val = newval;
3905                                 conf->gen.extra = conf->reset_extra = extra;
3906                                 break;
3907                         }
3908                 case PGC_INT:
3909                         {
3910                                 struct config_int *conf = (struct config_int *) gconf;
3911                                 int                     newval = conf->boot_val;
3912                                 void       *extra = NULL;
3913
3914                                 Assert(newval >= conf->min);
3915                                 Assert(newval <= conf->max);
3916                                 if (!call_int_check_hook(conf, &newval, &extra,
3917                                                                                  PGC_S_DEFAULT, LOG))
3918                                         elog(FATAL, "failed to initialize %s to %d",
3919                                                  conf->gen.name, newval);
3920                                 if (conf->assign_hook)
3921                                         (*conf->assign_hook) (newval, extra);
3922                                 *conf->variable = conf->reset_val = newval;
3923                                 conf->gen.extra = conf->reset_extra = extra;
3924                                 break;
3925                         }
3926                 case PGC_REAL:
3927                         {
3928                                 struct config_real *conf = (struct config_real *) gconf;
3929                                 double          newval = conf->boot_val;
3930                                 void       *extra = NULL;
3931
3932                                 Assert(newval >= conf->min);
3933                                 Assert(newval <= conf->max);
3934                                 if (!call_real_check_hook(conf, &newval, &extra,
3935                                                                                   PGC_S_DEFAULT, LOG))
3936                                         elog(FATAL, "failed to initialize %s to %g",
3937                                                  conf->gen.name, newval);
3938                                 if (conf->assign_hook)
3939                                         (*conf->assign_hook) (newval, extra);
3940                                 *conf->variable = conf->reset_val = newval;
3941                                 conf->gen.extra = conf->reset_extra = extra;
3942                                 break;
3943                         }
3944                 case PGC_STRING:
3945                         {
3946                                 struct config_string *conf = (struct config_string *) gconf;
3947                                 char       *newval;
3948                                 void       *extra = NULL;
3949
3950                                 /* non-NULL boot_val must always get strdup'd */
3951                                 if (conf->boot_val != NULL)
3952                                         newval = guc_strdup(FATAL, conf->boot_val);
3953                                 else
3954                                         newval = NULL;
3955
3956                                 if (!call_string_check_hook(conf, &newval, &extra,
3957                                                                                         PGC_S_DEFAULT, LOG))
3958                                         elog(FATAL, "failed to initialize %s to \"%s\"",
3959                                                  conf->gen.name, newval ? newval : "");
3960                                 if (conf->assign_hook)
3961                                         (*conf->assign_hook) (newval, extra);
3962                                 *conf->variable = conf->reset_val = newval;
3963                                 conf->gen.extra = conf->reset_extra = extra;
3964                                 break;
3965                         }
3966                 case PGC_ENUM:
3967                         {
3968                                 struct config_enum *conf = (struct config_enum *) gconf;
3969                                 int                     newval = conf->boot_val;
3970                                 void       *extra = NULL;
3971
3972                                 if (!call_enum_check_hook(conf, &newval, &extra,
3973                                                                                   PGC_S_DEFAULT, LOG))
3974                                         elog(FATAL, "failed to initialize %s to %d",
3975                                                  conf->gen.name, newval);
3976                                 if (conf->assign_hook)
3977                                         (*conf->assign_hook) (newval, extra);
3978                                 *conf->variable = conf->reset_val = newval;
3979                                 conf->gen.extra = conf->reset_extra = extra;
3980                                 break;
3981                         }
3982         }
3983 }
3984
3985
3986 /*
3987  * Select the configuration files and data directory to be used, and
3988  * do the initial read of postgresql.conf.
3989  *
3990  * This is called after processing command-line switches.
3991  *              userDoption is the -D switch value if any (NULL if unspecified).
3992  *              progname is just for use in error messages.
3993  *
3994  * Returns true on success; on failure, prints a suitable error message
3995  * to stderr and returns false.
3996  */
3997 bool
3998 SelectConfigFiles(const char *userDoption, const char *progname)
3999 {
4000         char       *configdir;
4001         char       *fname;
4002         struct stat stat_buf;
4003
4004         /* configdir is -D option, or $PGDATA if no -D */
4005         if (userDoption)
4006                 configdir = make_absolute_path(userDoption);
4007         else
4008                 configdir = make_absolute_path(getenv("PGDATA"));
4009
4010         /*
4011          * Find the configuration file: if config_file was specified on the
4012          * command line, use it, else use configdir/postgresql.conf.  In any case
4013          * ensure the result is an absolute path, so that it will be interpreted
4014          * the same way by future backends.
4015          */
4016         if (ConfigFileName)
4017                 fname = make_absolute_path(ConfigFileName);
4018         else if (configdir)
4019         {
4020                 fname = guc_malloc(FATAL,
4021                                                    strlen(configdir) + strlen(CONFIG_FILENAME) + 2);
4022                 sprintf(fname, "%s/%s", configdir, CONFIG_FILENAME);
4023         }
4024         else
4025         {
4026                 write_stderr("%s does not know where to find the server configuration file.\n"
4027                                          "You must specify the --config-file or -D invocation "
4028                                          "option or set the PGDATA environment variable.\n",
4029                                          progname);
4030                 return false;
4031         }
4032
4033         /*
4034          * Set the ConfigFileName GUC variable to its final value, ensuring that
4035          * it can't be overridden later.
4036          */
4037         SetConfigOption("config_file", fname, PGC_POSTMASTER, PGC_S_OVERRIDE);
4038         free(fname);
4039
4040         /*
4041          * Now read the config file for the first time.
4042          */
4043         if (stat(ConfigFileName, &stat_buf) != 0)
4044         {
4045                 write_stderr("%s cannot access the server configuration file \"%s\": %s\n",
4046                                          progname, ConfigFileName, strerror(errno));
4047                 return false;
4048         }
4049
4050         ProcessConfigFile(PGC_POSTMASTER);
4051
4052         /*
4053          * If the data_directory GUC variable has been set, use that as DataDir;
4054          * otherwise use configdir if set; else punt.
4055          *
4056          * Note: SetDataDir will copy and absolute-ize its argument, so we don't
4057          * have to.
4058          */
4059         if (data_directory)
4060                 SetDataDir(data_directory);
4061         else if (configdir)
4062                 SetDataDir(configdir);
4063         else
4064         {
4065                 write_stderr("%s does not know where to find the database system data.\n"
4066                                          "This can be specified as \"data_directory\" in \"%s\", "
4067                                          "or by the -D invocation option, or by the "
4068                                          "PGDATA environment variable.\n",
4069                                          progname, ConfigFileName);
4070                 return false;
4071         }
4072
4073         /*
4074          * Reflect the final DataDir value back into the data_directory GUC var.
4075          * (If you are wondering why we don't just make them a single variable,
4076          * it's because the EXEC_BACKEND case needs DataDir to be transmitted to
4077          * child backends specially.  XXX is that still true?  Given that we now
4078          * chdir to DataDir, EXEC_BACKEND can read the config file without knowing
4079          * DataDir in advance.)
4080          */
4081         SetConfigOption("data_directory", DataDir, PGC_POSTMASTER, PGC_S_OVERRIDE);
4082
4083         /*
4084          * If timezone_abbreviations wasn't set in the configuration file, install
4085          * the default value.  We do it this way because we can't safely install
4086          * a "real" value until my_exec_path is set, which may not have happened
4087          * when InitializeGUCOptions runs, so the bootstrap default value cannot
4088          * be the real desired default.
4089          */
4090         pg_timezone_abbrev_initialize();
4091
4092         /*
4093          * Figure out where pg_hba.conf is, and make sure the path is absolute.
4094          */
4095         if (HbaFileName)
4096                 fname = make_absolute_path(HbaFileName);
4097         else if (configdir)
4098         {
4099                 fname = guc_malloc(FATAL,
4100                                                    strlen(configdir) + strlen(HBA_FILENAME) + 2);
4101                 sprintf(fname, "%s/%s", configdir, HBA_FILENAME);
4102         }
4103         else
4104         {
4105                 write_stderr("%s does not know where to find the \"hba\" configuration file.\n"
4106                                          "This can be specified as \"hba_file\" in \"%s\", "
4107                                          "or by the -D invocation option, or by the "
4108                                          "PGDATA environment variable.\n",
4109                                          progname, ConfigFileName);
4110                 return false;
4111         }
4112         SetConfigOption("hba_file", fname, PGC_POSTMASTER, PGC_S_OVERRIDE);
4113         free(fname);
4114
4115         /*
4116          * Likewise for pg_ident.conf.
4117          */
4118         if (IdentFileName)
4119                 fname = make_absolute_path(IdentFileName);
4120         else if (configdir)
4121         {
4122                 fname = guc_malloc(FATAL,
4123                                                    strlen(configdir) + strlen(IDENT_FILENAME) + 2);
4124                 sprintf(fname, "%s/%s", configdir, IDENT_FILENAME);
4125         }
4126         else
4127         {
4128                 write_stderr("%s does not know where to find the \"ident\" configuration file.\n"
4129                                          "This can be specified as \"ident_file\" in \"%s\", "
4130                                          "or by the -D invocation option, or by the "
4131                                          "PGDATA environment variable.\n",
4132                                          progname, ConfigFileName);
4133                 return false;
4134         }
4135         SetConfigOption("ident_file", fname, PGC_POSTMASTER, PGC_S_OVERRIDE);
4136         free(fname);
4137
4138         free(configdir);
4139
4140         return true;
4141 }
4142
4143
4144 /*
4145  * Reset all options to their saved default values (implements RESET ALL)
4146  */
4147 void
4148 ResetAllOptions(void)
4149 {
4150         int                     i;
4151
4152         for (i = 0; i < num_guc_variables; i++)
4153         {
4154                 struct config_generic *gconf = guc_variables[i];
4155
4156                 /* Don't reset non-SET-able values */
4157                 if (gconf->context != PGC_SUSET &&
4158                         gconf->context != PGC_USERSET)
4159                         continue;
4160                 /* Don't reset if special exclusion from RESET ALL */
4161                 if (gconf->flags & GUC_NO_RESET_ALL)
4162                         continue;
4163                 /* No need to reset if wasn't SET */
4164                 if (gconf->source <= PGC_S_OVERRIDE)
4165                         continue;
4166
4167                 /* Save old value to support transaction abort */
4168                 push_old_value(gconf, GUC_ACTION_SET);
4169
4170                 switch (gconf->vartype)
4171                 {
4172                         case PGC_BOOL:
4173                                 {
4174                                         struct config_bool *conf = (struct config_bool *) gconf;
4175
4176                                         if (conf->assign_hook)
4177                                                 (*conf->assign_hook) (conf->reset_val,
4178                                                                                           conf->reset_extra);
4179                                         *conf->variable = conf->reset_val;
4180                                         set_extra_field(&conf->gen, &conf->gen.extra,
4181                                                                         conf->reset_extra);
4182                                         break;
4183                                 }
4184                         case PGC_INT:
4185                                 {
4186                                         struct config_int *conf = (struct config_int *) gconf;
4187
4188                                         if (conf->assign_hook)
4189                                                 (*conf->assign_hook) (conf->reset_val,
4190                                                                                           conf->reset_extra);
4191                                         *conf->variable = conf->reset_val;
4192                                         set_extra_field(&conf->gen, &conf->gen.extra,
4193                                                                         conf->reset_extra);
4194                                         break;
4195                                 }
4196                         case PGC_REAL:
4197                                 {
4198                                         struct config_real *conf = (struct config_real *) gconf;
4199
4200                                         if (conf->assign_hook)
4201                                                 (*conf->assign_hook) (conf->reset_val,
4202                                                                                           conf->reset_extra);
4203                                         *conf->variable = conf->reset_val;
4204                                         set_extra_field(&conf->gen, &conf->gen.extra,
4205                                                                         conf->reset_extra);
4206                                         break;
4207                                 }
4208                         case PGC_STRING:
4209                                 {
4210                                         struct config_string *conf = (struct config_string *) gconf;
4211
4212                                         if (conf->assign_hook)
4213                                                 (*conf->assign_hook) (conf->reset_val,
4214                                                                                           conf->reset_extra);
4215                                         set_string_field(conf, conf->variable, conf->reset_val);
4216                                         set_extra_field(&conf->gen, &conf->gen.extra,
4217                                                                         conf->reset_extra);
4218                                         break;
4219                                 }
4220                         case PGC_ENUM:
4221                                 {
4222                                         struct config_enum *conf = (struct config_enum *) gconf;
4223
4224                                         if (conf->assign_hook)
4225                                                 (*conf->assign_hook) (conf->reset_val,
4226                                                                                           conf->reset_extra);
4227                                         *conf->variable = conf->reset_val;
4228                                         set_extra_field(&conf->gen, &conf->gen.extra,
4229                                                                         conf->reset_extra);
4230                                         break;
4231                                 }
4232                 }
4233
4234                 gconf->source = gconf->reset_source;
4235                 gconf->scontext = gconf->reset_scontext;
4236
4237                 if (gconf->flags & GUC_REPORT)
4238                         ReportGUCOption(gconf);
4239         }
4240 }
4241
4242
4243 /*
4244  * push_old_value
4245  *              Push previous state during transactional assignment to a GUC variable.
4246  */
4247 static void
4248 push_old_value(struct config_generic * gconf, GucAction action)
4249 {
4250         GucStack   *stack;
4251
4252         /* If we're not inside a nest level, do nothing */
4253         if (GUCNestLevel == 0)
4254                 return;
4255
4256         /* Do we already have a stack entry of the current nest level? */
4257         stack = gconf->stack;
4258         if (stack && stack->nest_level >= GUCNestLevel)
4259         {
4260                 /* Yes, so adjust its state if necessary */
4261                 Assert(stack->nest_level == GUCNestLevel);
4262                 switch (action)
4263                 {
4264                         case GUC_ACTION_SET:
4265                                 /* SET overrides any prior action at same nest level */
4266                                 if (stack->state == GUC_SET_LOCAL)
4267                                 {
4268                                         /* must discard old masked value */
4269                                         discard_stack_value(gconf, &stack->masked);
4270                                 }
4271                                 stack->state = GUC_SET;
4272                                 break;
4273                         case GUC_ACTION_LOCAL:
4274                                 if (stack->state == GUC_SET)
4275                                 {
4276                                         /* SET followed by SET LOCAL, remember SET's value */
4277                                         stack->masked_scontext = gconf->scontext;
4278                                         set_stack_value(gconf, &stack->masked);
4279                                         stack->state = GUC_SET_LOCAL;
4280                                 }
4281                                 /* in all other cases, no change to stack entry */
4282                                 break;
4283                         case GUC_ACTION_SAVE:
4284                                 /* Could only have a prior SAVE of same variable */
4285                                 Assert(stack->state == GUC_SAVE);
4286                                 break;
4287                 }
4288                 Assert(guc_dirty);              /* must be set already */
4289                 return;
4290         }
4291
4292         /*
4293          * Push a new stack entry
4294          *
4295          * We keep all the stack entries in TopTransactionContext for simplicity.
4296          */
4297         stack = (GucStack *) MemoryContextAllocZero(TopTransactionContext,
4298                                                                                                 sizeof(GucStack));
4299
4300         stack->prev = gconf->stack;
4301         stack->nest_level = GUCNestLevel;
4302         switch (action)
4303         {
4304                 case GUC_ACTION_SET:
4305                         stack->state = GUC_SET;
4306                         break;
4307                 case GUC_ACTION_LOCAL:
4308                         stack->state = GUC_LOCAL;
4309                         break;
4310                 case GUC_ACTION_SAVE:
4311                         stack->state = GUC_SAVE;
4312                         break;
4313         }
4314         stack->source = gconf->source;
4315         stack->scontext = gconf->scontext;
4316         set_stack_value(gconf, &stack->prior);
4317
4318         gconf->stack = stack;
4319
4320         /* Ensure we remember to pop at end of xact */
4321         guc_dirty = true;
4322 }
4323
4324
4325 /*
4326  * Do GUC processing at main transaction start.
4327  */
4328 void
4329 AtStart_GUC(void)
4330 {
4331         /*
4332          * The nest level should be 0 between transactions; if it isn't, somebody
4333          * didn't call AtEOXact_GUC, or called it with the wrong nestLevel.  We
4334          * throw a warning but make no other effort to clean up.
4335          */
4336         if (GUCNestLevel != 0)
4337                 elog(WARNING, "GUC nest level = %d at transaction start",
4338                          GUCNestLevel);
4339         GUCNestLevel = 1;
4340 }
4341
4342 /*
4343  * Enter a new nesting level for GUC values.  This is called at subtransaction
4344  * start, and when entering a function that has proconfig settings, and in
4345  * some other places where we want to set GUC variables transiently.
4346  * NOTE we must not risk error here, else subtransaction start will be unhappy.
4347  */
4348 int
4349 NewGUCNestLevel(void)
4350 {
4351         return ++GUCNestLevel;
4352 }
4353
4354 /*
4355  * Do GUC processing at transaction or subtransaction commit or abort, or
4356  * when exiting a function that has proconfig settings, or when undoing a
4357  * transient assignment to some GUC variables.  (The name is thus a bit of
4358  * a misnomer; perhaps it should be ExitGUCNestLevel or some such.)
4359  * During abort, we discard all GUC settings that were applied at nesting
4360  * levels >= nestLevel.  nestLevel == 1 corresponds to the main transaction.
4361  */
4362 void
4363 AtEOXact_GUC(bool isCommit, int nestLevel)
4364 {
4365         bool            still_dirty;
4366         int                     i;
4367
4368         /*
4369          * Note: it's possible to get here with GUCNestLevel == nestLevel-1 during
4370          * abort, if there is a failure during transaction start before
4371          * AtStart_GUC is called.
4372          */
4373         Assert(nestLevel > 0 &&
4374                    (nestLevel <= GUCNestLevel ||
4375                         (nestLevel == GUCNestLevel + 1 && !isCommit)));
4376
4377         /* Quick exit if nothing's changed in this transaction */
4378         if (!guc_dirty)
4379         {
4380                 GUCNestLevel = nestLevel - 1;
4381                 return;
4382         }
4383
4384         still_dirty = false;
4385         for (i = 0; i < num_guc_variables; i++)
4386         {
4387                 struct config_generic *gconf = guc_variables[i];
4388                 GucStack   *stack;
4389
4390                 /*
4391                  * Process and pop each stack entry within the nest level. To simplify
4392                  * fmgr_security_definer() and other places that use GUC_ACTION_SAVE,
4393                  * we allow failure exit from code that uses a local nest level to be
4394                  * recovered at the surrounding transaction or subtransaction abort;
4395                  * so there could be more than one stack entry to pop.
4396                  */
4397                 while ((stack = gconf->stack) != NULL &&
4398                            stack->nest_level >= nestLevel)
4399                 {
4400                         GucStack   *prev = stack->prev;
4401                         bool            restorePrior = false;
4402                         bool            restoreMasked = false;
4403                         bool            changed;
4404
4405                         /*
4406                          * In this next bit, if we don't set either restorePrior or
4407                          * restoreMasked, we must "discard" any unwanted fields of the
4408                          * stack entries to avoid leaking memory.  If we do set one of
4409                          * those flags, unused fields will be cleaned up after restoring.
4410                          */
4411                         if (!isCommit)          /* if abort, always restore prior value */
4412                                 restorePrior = true;
4413                         else if (stack->state == GUC_SAVE)
4414                                 restorePrior = true;
4415                         else if (stack->nest_level == 1)
4416                         {
4417                                 /* transaction commit */
4418                                 if (stack->state == GUC_SET_LOCAL)
4419                                         restoreMasked = true;
4420                                 else if (stack->state == GUC_SET)
4421                                 {
4422                                         /* we keep the current active value */
4423                                         discard_stack_value(gconf, &stack->prior);
4424                                 }
4425                                 else    /* must be GUC_LOCAL */
4426                                         restorePrior = true;
4427                         }
4428                         else if (prev == NULL ||
4429                                          prev->nest_level < stack->nest_level - 1)
4430                         {
4431                                 /* decrement entry's level and do not pop it */
4432                                 stack->nest_level--;
4433                                 continue;
4434                         }
4435                         else
4436                         {
4437                                 /*
4438                                  * We have to merge this stack entry into prev. See README for
4439                                  * discussion of this bit.
4440                                  */
4441                                 switch (stack->state)
4442                                 {
4443                                         case GUC_SAVE:
4444                                                 Assert(false);  /* can't get here */
4445
4446                                         case GUC_SET:
4447                                                 /* next level always becomes SET */
4448                                                 discard_stack_value(gconf, &stack->prior);
4449                                                 if (prev->state == GUC_SET_LOCAL)
4450                                                         discard_stack_value(gconf, &prev->masked);
4451                                                 prev->state = GUC_SET;
4452                                                 break;
4453
4454                                         case GUC_LOCAL:
4455                                                 if (prev->state == GUC_SET)
4456                                                 {
4457                                                         /* LOCAL migrates down */
4458                                                         prev->masked_scontext = stack->scontext;
4459                                                         prev->masked = stack->prior;
4460                                                         prev->state = GUC_SET_LOCAL;
4461                                                 }
4462                                                 else
4463                                                 {
4464                                                         /* else just forget this stack level */
4465                                                         discard_stack_value(gconf, &stack->prior);
4466                                                 }
4467                                                 break;
4468
4469                                         case GUC_SET_LOCAL:
4470                                                 /* prior state at this level no longer wanted */
4471                                                 discard_stack_value(gconf, &stack->prior);
4472                                                 /* copy down the masked state */
4473                                                 prev->masked_scontext = stack->masked_scontext;
4474                                                 if (prev->state == GUC_SET_LOCAL)
4475                                                         discard_stack_value(gconf, &prev->masked);
4476                                                 prev->masked = stack->masked;
4477                                                 prev->state = GUC_SET_LOCAL;
4478                                                 break;
4479                                 }
4480                         }
4481
4482                         changed = false;
4483
4484                         if (restorePrior || restoreMasked)
4485                         {
4486                                 /* Perform appropriate restoration of the stacked value */
4487                                 config_var_value newvalue;
4488                                 GucSource       newsource;
4489                                 GucContext      newscontext;
4490
4491                                 if (restoreMasked)
4492                                 {
4493                                         newvalue = stack->masked;
4494                                         newsource = PGC_S_SESSION;
4495                                         newscontext = stack->masked_scontext;
4496                                 }
4497                                 else
4498                                 {
4499                                         newvalue = stack->prior;
4500                                         newsource = stack->source;
4501                                         newscontext = stack->scontext;
4502                                 }
4503
4504                                 switch (gconf->vartype)
4505                                 {
4506                                         case PGC_BOOL:
4507                                                 {
4508                                                         struct config_bool *conf = (struct config_bool *) gconf;
4509                                                         bool            newval = newvalue.val.boolval;
4510                                                         void       *newextra = newvalue.extra;
4511
4512                                                         if (*conf->variable != newval ||
4513                                                                 conf->gen.extra != newextra)
4514                                                         {
4515                                                                 if (conf->assign_hook)
4516                                                                         (*conf->assign_hook) (newval, newextra);
4517                                                                 *conf->variable = newval;
4518                                                                 set_extra_field(&conf->gen, &conf->gen.extra,
4519                                                                                                 newextra);
4520                                                                 changed = true;
4521                                                         }
4522                                                         break;
4523                                                 }
4524                                         case PGC_INT:
4525                                                 {
4526                                                         struct config_int *conf = (struct config_int *) gconf;
4527                                                         int                     newval = newvalue.val.intval;
4528                                                         void       *newextra = newvalue.extra;
4529
4530                                                         if (*conf->variable != newval ||
4531                                                                 conf->gen.extra != newextra)
4532                                                         {
4533                                                                 if (conf->assign_hook)
4534                                                                         (*conf->assign_hook) (newval, newextra);
4535                                                                 *conf->variable = newval;
4536                                                                 set_extra_field(&conf->gen, &conf->gen.extra,
4537                                                                                                 newextra);
4538                                                                 changed = true;
4539                                                         }
4540                                                         break;
4541                                                 }
4542                                         case PGC_REAL:
4543                                                 {
4544                                                         struct config_real *conf = (struct config_real *) gconf;
4545                                                         double          newval = newvalue.val.realval;
4546                                                         void       *newextra = newvalue.extra;
4547
4548                                                         if (*conf->variable != newval ||
4549                                                                 conf->gen.extra != newextra)
4550                                                         {
4551                                                                 if (conf->assign_hook)
4552                                                                         (*conf->assign_hook) (newval, newextra);
4553                                                                 *conf->variable = newval;
4554                                                                 set_extra_field(&conf->gen, &conf->gen.extra,
4555                                                                                                 newextra);
4556                                                                 changed = true;
4557                                                         }
4558                                                         break;
4559                                                 }
4560                                         case PGC_STRING:
4561                                                 {
4562                                                         struct config_string *conf = (struct config_string *) gconf;
4563                                                         char       *newval = newvalue.val.stringval;
4564                                                         void       *newextra = newvalue.extra;
4565
4566                                                         if (*conf->variable != newval ||
4567                                                                 conf->gen.extra != newextra)
4568                                                         {
4569                                                                 if (conf->assign_hook)
4570                                                                         (*conf->assign_hook) (newval, newextra);
4571                                                                 set_string_field(conf, conf->variable, newval);
4572                                                                 set_extra_field(&conf->gen, &conf->gen.extra,
4573                                                                                                 newextra);
4574                                                                 changed = true;
4575                                                         }
4576
4577                                                         /*
4578                                                          * Release stacked values if not used anymore. We
4579                                                          * could use discard_stack_value() here, but since
4580                                                          * we have type-specific code anyway, might as
4581                                                          * well inline it.
4582                                                          */
4583                                                         set_string_field(conf, &stack->prior.val.stringval, NULL);
4584                                                         set_string_field(conf, &stack->masked.val.stringval, NULL);
4585                                                         break;
4586                                                 }
4587                                         case PGC_ENUM:
4588                                                 {
4589                                                         struct config_enum *conf = (struct config_enum *) gconf;
4590                                                         int                     newval = newvalue.val.enumval;
4591                                                         void       *newextra = newvalue.extra;
4592
4593                                                         if (*conf->variable != newval ||
4594                                                                 conf->gen.extra != newextra)
4595                                                         {
4596                                                                 if (conf->assign_hook)
4597                                                                         (*conf->assign_hook) (newval, newextra);
4598                                                                 *conf->variable = newval;
4599                                                                 set_extra_field(&conf->gen, &conf->gen.extra,
4600                                                                                                 newextra);
4601                                                                 changed = true;
4602                                                         }
4603                                                         break;
4604                                                 }
4605                                 }
4606
4607                                 /*
4608                                  * Release stacked extra values if not used anymore.
4609                                  */
4610                                 set_extra_field(gconf, &(stack->prior.extra), NULL);
4611                                 set_extra_field(gconf, &(stack->masked.extra), NULL);
4612
4613                                 /* And restore source information */
4614                                 gconf->source = newsource;
4615                                 gconf->scontext = newscontext;
4616                         }
4617
4618                         /* Finish popping the state stack */
4619                         gconf->stack = prev;
4620                         pfree(stack);
4621
4622                         /* Report new value if we changed it */
4623                         if (changed && (gconf->flags & GUC_REPORT))
4624                                 ReportGUCOption(gconf);
4625                 }                                               /* end of stack-popping loop */
4626
4627                 if (stack != NULL)
4628                         still_dirty = true;
4629         }
4630
4631         /* If there are no remaining stack entries, we can reset guc_dirty */
4632         guc_dirty = still_dirty;
4633
4634         /* Update nesting level */
4635         GUCNestLevel = nestLevel - 1;
4636 }
4637
4638
4639 /*
4640  * Start up automatic reporting of changes to variables marked GUC_REPORT.
4641  * This is executed at completion of backend startup.
4642  */
4643 void
4644 BeginReportingGUCOptions(void)
4645 {
4646         int                     i;
4647
4648         /*
4649          * Don't do anything unless talking to an interactive frontend of protocol
4650          * 3.0 or later.
4651          */
4652         if (whereToSendOutput != DestRemote ||
4653                 PG_PROTOCOL_MAJOR(FrontendProtocol) < 3)
4654                 return;
4655
4656         reporting_enabled = true;
4657
4658         /* Transmit initial values of interesting variables */
4659         for (i = 0; i < num_guc_variables; i++)
4660         {
4661                 struct config_generic *conf = guc_variables[i];
4662
4663                 if (conf->flags & GUC_REPORT)
4664                         ReportGUCOption(conf);
4665         }
4666 }
4667
4668 /*
4669  * ReportGUCOption: if appropriate, transmit option value to frontend
4670  */
4671 static void
4672 ReportGUCOption(struct config_generic * record)
4673 {
4674         if (reporting_enabled && (record->flags & GUC_REPORT))
4675         {
4676                 char       *val = _ShowOption(record, false);
4677                 StringInfoData msgbuf;
4678
4679                 pq_beginmessage(&msgbuf, 'S');
4680                 pq_sendstring(&msgbuf, record->name);
4681                 pq_sendstring(&msgbuf, val);
4682                 pq_endmessage(&msgbuf);
4683
4684                 pfree(val);
4685         }
4686 }
4687
4688 /*
4689  * Try to parse value as an integer.  The accepted formats are the
4690  * usual decimal, octal, or hexadecimal formats, optionally followed by
4691  * a unit name if "flags" indicates a unit is allowed.
4692  *
4693  * If the string parses okay, return true, else false.
4694  * If okay and result is not NULL, return the value in *result.
4695  * If not okay and hintmsg is not NULL, *hintmsg is set to a suitable
4696  *      HINT message, or NULL if no hint provided.
4697  */
4698 bool
4699 parse_int(const char *value, int *result, int flags, const char **hintmsg)
4700 {
4701         int64           val;
4702         char       *endptr;
4703
4704         /* To suppress compiler warnings, always set output params */
4705         if (result)
4706                 *result = 0;
4707         if (hintmsg)
4708                 *hintmsg = NULL;
4709
4710         /* We assume here that int64 is at least as wide as long */
4711         errno = 0;
4712         val = strtol(value, &endptr, 0);
4713
4714         if (endptr == value)
4715                 return false;                   /* no HINT for integer syntax error */
4716
4717         if (errno == ERANGE || val != (int64) ((int32) val))
4718         {
4719                 if (hintmsg)
4720                         *hintmsg = gettext_noop("Value exceeds integer range.");
4721                 return false;
4722         }
4723
4724         /* allow whitespace between integer and unit */
4725         while (isspace((unsigned char) *endptr))
4726                 endptr++;
4727
4728         /* Handle possible unit */
4729         if (*endptr != '\0')
4730         {
4731                 /*
4732                  * Note: the multiple-switch coding technique here is a bit tedious,
4733                  * but seems necessary to avoid intermediate-value overflows.
4734                  */
4735                 if (flags & GUC_UNIT_MEMORY)
4736                 {
4737                         /* Set hint for use if no match or trailing garbage */
4738                         if (hintmsg)
4739                                 *hintmsg = gettext_noop("Valid units for this parameter are \"kB\", \"MB\", and \"GB\".");
4740
4741 #if BLCKSZ < 1024 || BLCKSZ > (1024*1024)
4742 #error BLCKSZ must be between 1KB and 1MB
4743 #endif
4744 #if XLOG_BLCKSZ < 1024 || XLOG_BLCKSZ > (1024*1024)
4745 #error XLOG_BLCKSZ must be between 1KB and 1MB
4746 #endif
4747
4748                         if (strncmp(endptr, "kB", 2) == 0)
4749                         {
4750                                 endptr += 2;
4751                                 switch (flags & GUC_UNIT_MEMORY)
4752                                 {
4753                                         case GUC_UNIT_BLOCKS:
4754                                                 val /= (BLCKSZ / 1024);
4755                                                 break;
4756                                         case GUC_UNIT_XBLOCKS:
4757                                                 val /= (XLOG_BLCKSZ / 1024);
4758                                                 break;
4759                                 }
4760                         }
4761                         else if (strncmp(endptr, "MB", 2) == 0)
4762                         {
4763                                 endptr += 2;
4764                                 switch (flags & GUC_UNIT_MEMORY)
4765                                 {
4766                                         case GUC_UNIT_KB:
4767                                                 val *= KB_PER_MB;
4768                                                 break;
4769                                         case GUC_UNIT_BLOCKS:
4770                                                 val *= KB_PER_MB / (BLCKSZ / 1024);
4771                                                 break;
4772                                         case GUC_UNIT_XBLOCKS:
4773                                                 val *= KB_PER_MB / (XLOG_BLCKSZ / 1024);
4774                                                 break;
4775                                 }
4776                         }
4777                         else if (strncmp(endptr, "GB", 2) == 0)
4778                         {
4779                                 endptr += 2;
4780                                 switch (flags & GUC_UNIT_MEMORY)
4781                                 {
4782                                         case GUC_UNIT_KB:
4783                                                 val *= KB_PER_GB;
4784                                                 break;
4785                                         case GUC_UNIT_BLOCKS:
4786                                                 val *= KB_PER_GB / (BLCKSZ / 1024);
4787                                                 break;
4788                                         case GUC_UNIT_XBLOCKS:
4789                                                 val *= KB_PER_GB / (XLOG_BLCKSZ / 1024);
4790                                                 break;
4791                                 }
4792                         }
4793                 }
4794                 else if (flags & GUC_UNIT_TIME)
4795                 {
4796                         /* Set hint for use if no match or trailing garbage */
4797                         if (hintmsg)
4798                                 *hintmsg = gettext_noop("Valid units for this parameter are \"ms\", \"s\", \"min\", \"h\", and \"d\".");
4799
4800                         if (strncmp(endptr, "ms", 2) == 0)
4801                         {
4802                                 endptr += 2;
4803                                 switch (flags & GUC_UNIT_TIME)
4804                                 {
4805                                         case GUC_UNIT_S:
4806                                                 val /= MS_PER_S;
4807                                                 break;
4808                                         case GUC_UNIT_MIN:
4809                                                 val /= MS_PER_MIN;
4810                                                 break;
4811                                 }
4812                         }
4813                         else if (strncmp(endptr, "s", 1) == 0)
4814                         {
4815                                 endptr += 1;
4816                                 switch (flags & GUC_UNIT_TIME)
4817                                 {
4818                                         case GUC_UNIT_MS:
4819                                                 val *= MS_PER_S;
4820                                                 break;
4821                                         case GUC_UNIT_MIN:
4822                                                 val /= S_PER_MIN;
4823                                                 break;
4824                                 }
4825                         }
4826                         else if (strncmp(endptr, "min", 3) == 0)
4827                         {
4828                                 endptr += 3;
4829                                 switch (flags & GUC_UNIT_TIME)
4830                                 {
4831                                         case GUC_UNIT_MS:
4832                                                 val *= MS_PER_MIN;
4833                                                 break;
4834                                         case GUC_UNIT_S:
4835                                                 val *= S_PER_MIN;
4836                                                 break;
4837                                 }
4838                         }
4839                         else if (strncmp(endptr, "h", 1) == 0)
4840                         {
4841                                 endptr += 1;
4842                                 switch (flags & GUC_UNIT_TIME)
4843                                 {
4844                                         case GUC_UNIT_MS:
4845                                                 val *= MS_PER_H;
4846                                                 break;
4847                                         case GUC_UNIT_S:
4848                                                 val *= S_PER_H;
4849                                                 break;
4850                                         case GUC_UNIT_MIN:
4851                                                 val *= MIN_PER_H;
4852                                                 break;
4853                                 }
4854                         }
4855                         else if (strncmp(endptr, "d", 1) == 0)
4856                         {
4857                                 endptr += 1;
4858                                 switch (flags & GUC_UNIT_TIME)
4859                                 {
4860                                         case GUC_UNIT_MS:
4861                                                 val *= MS_PER_D;
4862                                                 break;
4863                                         case GUC_UNIT_S:
4864                                                 val *= S_PER_D;
4865                                                 break;
4866                                         case GUC_UNIT_MIN:
4867                                                 val *= MIN_PER_D;
4868                                                 break;
4869                                 }
4870                         }
4871                 }
4872
4873                 /* allow whitespace after unit */
4874                 while (isspace((unsigned char) *endptr))
4875                         endptr++;
4876
4877                 if (*endptr != '\0')
4878                         return false;           /* appropriate hint, if any, already set */
4879
4880                 /* Check for overflow due to units conversion */
4881                 if (val != (int64) ((int32) val))
4882                 {
4883                         if (hintmsg)
4884                                 *hintmsg = gettext_noop("Value exceeds integer range.");
4885                         return false;
4886                 }
4887         }
4888
4889         if (result)
4890                 *result = (int) val;
4891         return true;
4892 }
4893
4894
4895
4896 /*
4897  * Try to parse value as a floating point number in the usual format.
4898  * If the string parses okay, return true, else false.
4899  * If okay and result is not NULL, return the value in *result.
4900  */
4901 bool
4902 parse_real(const char *value, double *result)
4903 {
4904         double          val;
4905         char       *endptr;
4906
4907         if (result)
4908                 *result = 0;                    /* suppress compiler warning */
4909
4910         errno = 0;
4911         val = strtod(value, &endptr);
4912         if (endptr == value || errno == ERANGE)
4913                 return false;
4914
4915         /* allow whitespace after number */
4916         while (isspace((unsigned char) *endptr))
4917                 endptr++;
4918         if (*endptr != '\0')
4919                 return false;
4920
4921         if (result)
4922                 *result = val;
4923         return true;
4924 }
4925
4926
4927 /*
4928  * Lookup the name for an enum option with the selected value.
4929  * Should only ever be called with known-valid values, so throws
4930  * an elog(ERROR) if the enum option is not found.
4931  *
4932  * The returned string is a pointer to static data and not
4933  * allocated for modification.
4934  */
4935 const char *
4936 config_enum_lookup_by_value(struct config_enum * record, int val)
4937 {
4938         const struct config_enum_entry *entry;
4939
4940         for (entry = record->options; entry && entry->name; entry++)
4941         {
4942                 if (entry->val == val)
4943                         return entry->name;
4944         }
4945
4946         elog(ERROR, "could not find enum option %d for %s",
4947                  val, record->gen.name);
4948         return NULL;                            /* silence compiler */
4949 }
4950
4951
4952 /*
4953  * Lookup the value for an enum option with the selected name
4954  * (case-insensitive).
4955  * If the enum option is found, sets the retval value and returns
4956  * true. If it's not found, return FALSE and retval is set to 0.
4957  */
4958 bool
4959 config_enum_lookup_by_name(struct config_enum * record, const char *value,
4960                                                    int *retval)
4961 {
4962         const struct config_enum_entry *entry;
4963
4964         for (entry = record->options; entry && entry->name; entry++)
4965         {
4966                 if (pg_strcasecmp(value, entry->name) == 0)
4967                 {
4968                         *retval = entry->val;
4969                         return TRUE;
4970                 }
4971         }
4972
4973         *retval = 0;
4974         return FALSE;
4975 }
4976
4977
4978 /*
4979  * Return a list of all available options for an enum, excluding
4980  * hidden ones, separated by the given separator.
4981  * If prefix is non-NULL, it is added before the first enum value.
4982  * If suffix is non-NULL, it is added to the end of the string.
4983  */
4984 static char *
4985 config_enum_get_options(struct config_enum * record, const char *prefix,
4986                                                 const char *suffix, const char *separator)
4987 {
4988         const struct config_enum_entry *entry;
4989         StringInfoData retstr;
4990         int                     seplen;
4991
4992         initStringInfo(&retstr);
4993         appendStringInfoString(&retstr, prefix);
4994
4995         seplen = strlen(separator);
4996         for (entry = record->options; entry && entry->name; entry++)
4997         {
4998                 if (!entry->hidden)
4999                 {
5000                         appendStringInfoString(&retstr, entry->name);
5001                         appendBinaryStringInfo(&retstr, separator, seplen);
5002                 }
5003         }
5004
5005         /*
5006          * All the entries may have been hidden, leaving the string empty if no
5007          * prefix was given. This indicates a broken GUC setup, since there is no
5008          * use for an enum without any values, so we just check to make sure we
5009          * don't write to invalid memory instead of actually trying to do
5010          * something smart with it.
5011          */
5012         if (retstr.len >= seplen)
5013         {
5014                 /* Replace final separator */
5015                 retstr.data[retstr.len - seplen] = '\0';
5016                 retstr.len -= seplen;
5017         }
5018
5019         appendStringInfoString(&retstr, suffix);
5020
5021         return retstr.data;
5022 }
5023
5024
5025 /*
5026  * Sets option `name' to given value.
5027  *
5028  * The value should be a string, which will be parsed and converted to
5029  * the appropriate data type.  The context and source parameters indicate
5030  * in which context this function is being called, so that it can apply the
5031  * access restrictions properly.
5032  *
5033  * If value is NULL, set the option to its default value (normally the
5034  * reset_val, but if source == PGC_S_DEFAULT we instead use the boot_val).
5035  *
5036  * action indicates whether to set the value globally in the session, locally
5037  * to the current top transaction, or just for the duration of a function call.
5038  *
5039  * If changeVal is false then don't really set the option but do all
5040  * the checks to see if it would work.
5041  *
5042  * elevel should normally be passed as zero, allowing this function to make
5043  * its standard choice of ereport level.  However some callers need to be
5044  * able to override that choice; they should pass the ereport level to use.
5045  *
5046  * Return value:
5047  *      +1: the value is valid and was successfully applied.
5048  *      0:  the name or value is invalid (but see below).
5049  *      -1: the value was not applied because of context, priority, or changeVal.
5050  *
5051  * If there is an error (non-existing option, invalid value) then an
5052  * ereport(ERROR) is thrown *unless* this is called for a source for which
5053  * we don't want an ERROR (currently, those are defaults, the config file,
5054  * and per-database or per-user settings, as well as callers who specify
5055  * a less-than-ERROR elevel).  In those cases we write a suitable error
5056  * message via ereport() and return 0.
5057  *
5058  * See also SetConfigOption for an external interface.
5059  */
5060 int
5061 set_config_option(const char *name, const char *value,
5062                                   GucContext context, GucSource source,
5063                                   GucAction action, bool changeVal, int elevel)
5064 {
5065         struct config_generic *record;
5066         bool            prohibitValueChange = false;
5067         bool            makeDefault;
5068
5069         if (elevel == 0)
5070         {
5071                 if (source == PGC_S_DEFAULT || source == PGC_S_FILE)
5072                 {
5073                         /*
5074                          * To avoid cluttering the log, only the postmaster bleats loudly
5075                          * about problems with the config file.
5076                          */
5077                         elevel = IsUnderPostmaster ? DEBUG3 : LOG;
5078                 }
5079                 else if (source == PGC_S_DATABASE || source == PGC_S_USER ||
5080                                  source == PGC_S_DATABASE_USER)
5081                         elevel = WARNING;
5082                 else
5083                         elevel = ERROR;
5084         }
5085
5086         record = find_option(name, true, elevel);
5087         if (record == NULL)
5088         {
5089                 ereport(elevel,
5090                                 (errcode(ERRCODE_UNDEFINED_OBJECT),
5091                            errmsg("unrecognized configuration parameter \"%s\"", name)));
5092                 return 0;
5093         }
5094
5095         /*
5096          * Check if the option can be set at this time. See guc.h for the precise
5097          * rules.
5098          */
5099         switch (record->context)
5100         {
5101                 case PGC_INTERNAL:
5102                         if (context != PGC_INTERNAL)
5103                         {
5104                                 ereport(elevel,
5105                                                 (errcode(ERRCODE_CANT_CHANGE_RUNTIME_PARAM),
5106                                                  errmsg("parameter \"%s\" cannot be changed",
5107                                                                 name)));
5108                                 return 0;
5109                         }
5110                         break;
5111                 case PGC_POSTMASTER:
5112                         if (context == PGC_SIGHUP)
5113                         {
5114                                 /*
5115                                  * We are re-reading a PGC_POSTMASTER variable from
5116                                  * postgresql.conf.  We can't change the setting, so we should
5117                                  * give a warning if the DBA tries to change it.  However,
5118                                  * because of variant formats, canonicalization by check
5119                                  * hooks, etc, we can't just compare the given string directly
5120                                  * to what's stored.  Set a flag to check below after we have
5121                                  * the final storable value.
5122                                  */
5123                                 prohibitValueChange = true;
5124                         }
5125                         else if (context != PGC_POSTMASTER)
5126                         {
5127                                 ereport(elevel,
5128                                                 (errcode(ERRCODE_CANT_CHANGE_RUNTIME_PARAM),
5129                                                  errmsg("parameter \"%s\" cannot be changed without restarting the server",
5130                                                                 name)));
5131                                 return 0;
5132                         }
5133                         break;
5134                 case PGC_SIGHUP:
5135                         if (context != PGC_SIGHUP && context != PGC_POSTMASTER)
5136                         {
5137                                 ereport(elevel,
5138                                                 (errcode(ERRCODE_CANT_CHANGE_RUNTIME_PARAM),
5139                                                  errmsg("parameter \"%s\" cannot be changed now",
5140                                                                 name)));
5141                                 return 0;
5142                         }
5143
5144                         /*
5145                          * Hmm, the idea of the SIGHUP context is "ought to be global, but
5146                          * can be changed after postmaster start". But there's nothing
5147                          * that prevents a crafty administrator from sending SIGHUP
5148                          * signals to individual backends only.
5149                          */
5150                         break;
5151                 case PGC_BACKEND:
5152                         if (context == PGC_SIGHUP)
5153                         {
5154                                 /*
5155                                  * If a PGC_BACKEND parameter is changed in the config file,
5156                                  * we want to accept the new value in the postmaster (whence
5157                                  * it will propagate to subsequently-started backends), but
5158                                  * ignore it in existing backends.      This is a tad klugy, but
5159                                  * necessary because we don't re-read the config file during
5160                                  * backend start.
5161                                  */
5162                                 if (IsUnderPostmaster)
5163                                         return -1;
5164                         }
5165                         else if (context != PGC_POSTMASTER && context != PGC_BACKEND &&
5166                                          source != PGC_S_CLIENT)
5167                         {
5168                                 ereport(elevel,
5169                                                 (errcode(ERRCODE_CANT_CHANGE_RUNTIME_PARAM),
5170                                                  errmsg("parameter \"%s\" cannot be set after connection start",
5171                                                                 name)));
5172                                 return 0;
5173                         }
5174                         break;
5175                 case PGC_SUSET:
5176                         if (context == PGC_USERSET || context == PGC_BACKEND)
5177                         {
5178                                 ereport(elevel,
5179                                                 (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
5180                                                  errmsg("permission denied to set parameter \"%s\"",
5181                                                                 name)));
5182                                 return 0;
5183                         }
5184                         break;
5185                 case PGC_USERSET:
5186                         /* always okay */
5187                         break;
5188         }
5189
5190         /*
5191          * Disallow changing GUC_NOT_WHILE_SEC_REST values if we are inside a
5192          * security restriction context.  We can reject this regardless of the GUC
5193          * context or source, mainly because sources that it might be reasonable
5194          * to override for won't be seen while inside a function.
5195          *
5196          * Note: variables marked GUC_NOT_WHILE_SEC_REST should usually be marked
5197          * GUC_NO_RESET_ALL as well, because ResetAllOptions() doesn't check this.
5198          * An exception might be made if the reset value is assumed to be "safe".
5199          *
5200          * Note: this flag is currently used for "session_authorization" and
5201          * "role".      We need to prohibit changing these inside a local userid
5202          * context because when we exit it, GUC won't be notified, leaving things
5203          * out of sync.  (This could be fixed by forcing a new GUC nesting level,
5204          * but that would change behavior in possibly-undesirable ways.)  Also, we
5205          * prohibit changing these in a security-restricted operation because
5206          * otherwise RESET could be used to regain the session user's privileges.
5207          */
5208         if (record->flags & GUC_NOT_WHILE_SEC_REST)
5209         {
5210                 if (InLocalUserIdChange())
5211                 {
5212                         /*
5213                          * Phrasing of this error message is historical, but it's the most
5214                          * common case.
5215                          */
5216                         ereport(elevel,
5217                                         (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
5218                                          errmsg("cannot set parameter \"%s\" within security-definer function",
5219                                                         name)));
5220                         return 0;
5221                 }
5222                 if (InSecurityRestrictedOperation())
5223                 {
5224                         ereport(elevel,
5225                                         (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
5226                                          errmsg("cannot set parameter \"%s\" within security-restricted operation",
5227                                                         name)));
5228                         return 0;
5229                 }
5230         }
5231
5232         /*
5233          * Should we set reset/stacked values?  (If so, the behavior is not
5234          * transactional.)      This is done either when we get a default value from
5235          * the database's/user's/client's default settings or when we reset a
5236          * value to its default.
5237          */
5238         makeDefault = changeVal && (source <= PGC_S_OVERRIDE) &&
5239                 ((value != NULL) || source == PGC_S_DEFAULT);
5240
5241         /*
5242          * Ignore attempted set if overridden by previously processed setting.
5243          * However, if changeVal is false then plow ahead anyway since we are
5244          * trying to find out if the value is potentially good, not actually use
5245          * it. Also keep going if makeDefault is true, since we may want to set
5246          * the reset/stacked values even if we can't set the variable itself.
5247          */
5248         if (record->source > source)
5249         {
5250                 if (changeVal && !makeDefault)
5251                 {
5252                         elog(DEBUG3, "\"%s\": setting ignored because previous source is higher priority",
5253                                  name);
5254                         return -1;
5255                 }
5256                 changeVal = false;
5257         }
5258
5259         /*
5260          * Evaluate value and set variable.
5261          */
5262         switch (record->vartype)
5263         {
5264                 case PGC_BOOL:
5265                         {
5266                                 struct config_bool *conf = (struct config_bool *) record;
5267                                 bool            newval;
5268                                 void       *newextra = NULL;
5269
5270                                 if (value)
5271                                 {
5272                                         if (!parse_bool(value, &newval))
5273                                         {
5274                                                 ereport(elevel,
5275                                                                 (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
5276                                                   errmsg("parameter \"%s\" requires a Boolean value",
5277                                                                  name)));
5278                                                 return 0;
5279                                         }
5280                                         if (!call_bool_check_hook(conf, &newval, &newextra,
5281                                                                                           source, elevel))
5282                                                 return 0;
5283                                 }
5284                                 else if (source == PGC_S_DEFAULT)
5285                                 {
5286                                         newval = conf->boot_val;
5287                                         if (!call_bool_check_hook(conf, &newval, &newextra,
5288                                                                                           source, elevel))
5289                                                 return 0;
5290                                 }
5291                                 else
5292                                 {
5293                                         newval = conf->reset_val;
5294                                         newextra = conf->reset_extra;
5295                                         source = conf->gen.reset_source;
5296                                         context = conf->gen.reset_scontext;
5297                                 }
5298
5299                                 if (prohibitValueChange)
5300                                 {
5301                                         if (*conf->variable != newval)
5302                                         {
5303                                                 ereport(elevel,
5304                                                                 (errcode(ERRCODE_CANT_CHANGE_RUNTIME_PARAM),
5305                                                                  errmsg("parameter \"%s\" cannot be changed without restarting the server",
5306                                                                                 name)));
5307                                                 return 0;
5308                                         }
5309                                         return -1;
5310                                 }
5311
5312                                 if (changeVal)
5313                                 {
5314                                         /* Save old value to support transaction abort */
5315                                         if (!makeDefault)
5316                                                 push_old_value(&conf->gen, action);
5317
5318                                         if (conf->assign_hook)
5319                                                 (*conf->assign_hook) (newval, newextra);
5320                                         *conf->variable = newval;
5321                                         set_extra_field(&conf->gen, &conf->gen.extra,
5322                                                                         newextra);
5323                                         conf->gen.source = source;
5324                                         conf->gen.scontext = context;
5325                                 }
5326                                 if (makeDefault)
5327                                 {
5328                                         GucStack   *stack;
5329
5330                                         if (conf->gen.reset_source <= source)
5331                                         {
5332                                                 conf->reset_val = newval;
5333                                                 set_extra_field(&conf->gen, &conf->reset_extra,
5334                                                                                 newextra);
5335                                                 conf->gen.reset_source = source;
5336                                                 conf->gen.reset_scontext = context;
5337                                         }
5338                                         for (stack = conf->gen.stack; stack; stack = stack->prev)
5339                                         {
5340                                                 if (stack->source <= source)
5341                                                 {
5342                                                         stack->prior.val.boolval = newval;
5343                                                         set_extra_field(&conf->gen, &stack->prior.extra,
5344                                                                                         newextra);
5345                                                         stack->source = source;
5346                                                         stack->scontext = context;
5347                                                 }
5348                                         }
5349                                 }
5350
5351                                 /* Perhaps we didn't install newextra anywhere */
5352                                 if (newextra && !extra_field_used(&conf->gen, newextra))
5353                                         free(newextra);
5354                                 break;
5355                         }
5356
5357                 case PGC_INT:
5358                         {
5359                                 struct config_int *conf = (struct config_int *) record;
5360                                 int                     newval;
5361                                 void       *newextra = NULL;
5362
5363                                 if (value)
5364                                 {
5365                                         const char *hintmsg;
5366
5367                                         if (!parse_int(value, &newval, conf->gen.flags, &hintmsg))
5368                                         {
5369                                                 ereport(elevel,
5370                                                                 (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
5371                                                  errmsg("invalid value for parameter \"%s\": \"%s\"",
5372                                                                 name, value),
5373                                                                  hintmsg ? errhint("%s", _(hintmsg)) : 0));
5374                                                 return 0;
5375                                         }
5376                                         if (newval < conf->min || newval > conf->max)
5377                                         {
5378                                                 ereport(elevel,
5379                                                                 (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
5380                                                                  errmsg("%d is outside the valid range for parameter \"%s\" (%d .. %d)",
5381                                                                                 newval, name, conf->min, conf->max)));
5382                                                 return 0;
5383                                         }
5384                                         if (!call_int_check_hook(conf, &newval, &newextra,
5385                                                                                          source, elevel))
5386                                                 return 0;
5387                                 }
5388                                 else if (source == PGC_S_DEFAULT)
5389                                 {
5390                                         newval = conf->boot_val;
5391                                         if (!call_int_check_hook(conf, &newval, &newextra,
5392                                                                                          source, elevel))
5393                                                 return 0;
5394                                 }
5395                                 else
5396                                 {
5397                                         newval = conf->reset_val;
5398                                         newextra = conf->reset_extra;
5399                                         source = conf->gen.reset_source;
5400                                         context = conf->gen.reset_scontext;
5401                                 }
5402
5403                                 if (prohibitValueChange)
5404                                 {
5405                                         if (*conf->variable != newval)
5406                                         {
5407                                                 ereport(elevel,
5408                                                                 (errcode(ERRCODE_CANT_CHANGE_RUNTIME_PARAM),
5409                                                                  errmsg("parameter \"%s\" cannot be changed without restarting the server",
5410                                                                                 name)));
5411                                                 return 0;
5412                                         }
5413                                         return -1;
5414                                 }
5415
5416                                 if (changeVal)
5417                                 {
5418                                         /* Save old value to support transaction abort */
5419                                         if (!makeDefault)
5420                                                 push_old_value(&conf->gen, action);
5421
5422                                         if (conf->assign_hook)
5423                                                 (*conf->assign_hook) (newval, newextra);
5424                                         *conf->variable = newval;
5425                                         set_extra_field(&conf->gen, &conf->gen.extra,
5426                                                                         newextra);
5427                                         conf->gen.source = source;
5428                                         conf->gen.scontext = context;
5429                                 }
5430                                 if (makeDefault)
5431                                 {
5432                                         GucStack   *stack;
5433
5434                                         if (conf->gen.reset_source <= source)
5435                                         {
5436                                                 conf->reset_val = newval;
5437                                                 set_extra_field(&conf->gen, &conf->reset_extra,
5438                                                                                 newextra);
5439                                                 conf->gen.reset_source = source;
5440                                                 conf->gen.reset_scontext = context;
5441                                         }
5442                                         for (stack = conf->gen.stack; stack; stack = stack->prev)
5443                                         {
5444                                                 if (stack->source <= source)
5445                                                 {
5446                                                         stack->prior.val.intval = newval;
5447                                                         set_extra_field(&conf->gen, &stack->prior.extra,
5448                                                                                         newextra);
5449                                                         stack->source = source;
5450                                                         stack->scontext = context;
5451                                                 }
5452                                         }
5453                                 }
5454
5455                                 /* Perhaps we didn't install newextra anywhere */
5456                                 if (newextra && !extra_field_used(&conf->gen, newextra))
5457                                         free(newextra);
5458                                 break;
5459                         }
5460
5461                 case PGC_REAL:
5462                         {
5463                                 struct config_real *conf = (struct config_real *) record;
5464                                 double          newval;
5465                                 void       *newextra = NULL;
5466
5467                                 if (value)
5468                                 {
5469                                         if (!parse_real(value, &newval))
5470                                         {
5471                                                 ereport(elevel,
5472                                                                 (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
5473                                                   errmsg("parameter \"%s\" requires a numeric value",
5474                                                                  name)));
5475                                                 return 0;
5476                                         }
5477                                         if (newval < conf->min || newval > conf->max)
5478                                         {
5479                                                 ereport(elevel,
5480                                                                 (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
5481                                                                  errmsg("%g is outside the valid range for parameter \"%s\" (%g .. %g)",
5482                                                                                 newval, name, conf->min, conf->max)));
5483                                                 return 0;
5484                                         }
5485                                         if (!call_real_check_hook(conf, &newval, &newextra,
5486                                                                                           source, elevel))
5487                                                 return 0;
5488                                 }
5489                                 else if (source == PGC_S_DEFAULT)
5490                                 {
5491                                         newval = conf->boot_val;
5492                                         if (!call_real_check_hook(conf, &newval, &newextra,
5493                                                                                           source, elevel))
5494                                                 return 0;
5495                                 }
5496                                 else
5497                                 {
5498                                         newval = conf->reset_val;
5499                                         newextra = conf->reset_extra;
5500                                         source = conf->gen.reset_source;
5501                                         context = conf->gen.reset_scontext;
5502                                 }
5503
5504                                 if (prohibitValueChange)
5505                                 {
5506                                         if (*conf->variable != newval)
5507                                         {
5508                                                 ereport(elevel,
5509                                                                 (errcode(ERRCODE_CANT_CHANGE_RUNTIME_PARAM),
5510                                                                  errmsg("parameter \"%s\" cannot be changed without restarting the server",
5511                                                                                 name)));
5512                                                 return 0;
5513                                         }
5514                                         return -1;
5515                                 }
5516
5517                                 if (changeVal)
5518                                 {
5519                                         /* Save old value to support transaction abort */
5520                                         if (!makeDefault)
5521                                                 push_old_value(&conf->gen, action);
5522
5523                                         if (conf->assign_hook)
5524                                                 (*conf->assign_hook) (newval, newextra);
5525                                         *conf->variable = newval;
5526                                         set_extra_field(&conf->gen, &conf->gen.extra,
5527                                                                         newextra);
5528                                         conf->gen.source = source;
5529                                         conf->gen.scontext = context;
5530                                 }
5531                                 if (makeDefault)
5532                                 {
5533                                         GucStack   *stack;
5534
5535                                         if (conf->gen.reset_source <= source)
5536                                         {
5537                                                 conf->reset_val = newval;
5538                                                 set_extra_field(&conf->gen, &conf->reset_extra,
5539                                                                                 newextra);
5540                                                 conf->gen.reset_source = source;
5541                                                 conf->gen.reset_scontext = context;
5542                                         }
5543                                         for (stack = conf->gen.stack; stack; stack = stack->prev)
5544                                         {
5545                                                 if (stack->source <= source)
5546                                                 {
5547                                                         stack->prior.val.realval = newval;
5548                                                         set_extra_field(&conf->gen, &stack->prior.extra,
5549                                                                                         newextra);
5550                                                         stack->source = source;
5551                                                         stack->scontext = context;
5552                                                 }
5553                                         }
5554                                 }
5555
5556                                 /* Perhaps we didn't install newextra anywhere */
5557                                 if (newextra && !extra_field_used(&conf->gen, newextra))
5558                                         free(newextra);
5559                                 break;
5560                         }
5561
5562                 case PGC_STRING:
5563                         {
5564                                 struct config_string *conf = (struct config_string *) record;
5565                                 char       *newval;
5566                                 void       *newextra = NULL;
5567
5568                                 if (value)
5569                                 {
5570                                         /*
5571                                          * The value passed by the caller could be transient, so
5572                                          * we always strdup it.
5573                                          */
5574                                         newval = guc_strdup(elevel, value);
5575                                         if (newval == NULL)
5576                                                 return 0;
5577
5578                                         /*
5579                                          * The only built-in "parsing" check we have is to apply
5580                                          * truncation if GUC_IS_NAME.
5581                                          */
5582                                         if (conf->gen.flags & GUC_IS_NAME)
5583                                                 truncate_identifier(newval, strlen(newval), true);
5584
5585                                         if (!call_string_check_hook(conf, &newval, &newextra,
5586                                                                                                 source, elevel))
5587                                         {
5588                                                 free(newval);
5589                                                 return 0;
5590                                         }
5591                                 }
5592                                 else if (source == PGC_S_DEFAULT)
5593                                 {
5594                                         /* non-NULL boot_val must always get strdup'd */
5595                                         if (conf->boot_val != NULL)
5596                                         {
5597                                                 newval = guc_strdup(elevel, conf->boot_val);
5598                                                 if (newval == NULL)
5599                                                         return 0;
5600                                         }
5601                                         else
5602                                                 newval = NULL;
5603
5604                                         if (!call_string_check_hook(conf, &newval, &newextra,
5605                                                                                                 source, elevel))
5606                                         {
5607                                                 free(newval);
5608                                                 return 0;
5609                                         }
5610                                 }
5611                                 else
5612                                 {
5613                                         /*
5614                                          * strdup not needed, since reset_val is already under
5615                                          * guc.c's control
5616                                          */
5617                                         newval = conf->reset_val;
5618                                         newextra = conf->reset_extra;
5619                                         source = conf->gen.reset_source;
5620                                         context = conf->gen.reset_scontext;
5621                                 }
5622
5623                                 if (prohibitValueChange)
5624                                 {
5625                                         /* newval shouldn't be NULL, so we're a bit sloppy here */
5626                                         if (*conf->variable == NULL || newval == NULL ||
5627                                                 strcmp(*conf->variable, newval) != 0)
5628                                         {
5629                                                 ereport(elevel,
5630                                                                 (errcode(ERRCODE_CANT_CHANGE_RUNTIME_PARAM),
5631                                                                  errmsg("parameter \"%s\" cannot be changed without restarting the server",
5632                                                                                 name)));
5633                                                 return 0;
5634                                         }
5635                                         return -1;
5636                                 }
5637
5638                                 if (changeVal)
5639                                 {
5640                                         /* Save old value to support transaction abort */
5641                                         if (!makeDefault)
5642                                                 push_old_value(&conf->gen, action);
5643
5644                                         if (conf->assign_hook)
5645                                                 (*conf->assign_hook) (newval, newextra);
5646                                         set_string_field(conf, conf->variable, newval);
5647                                         set_extra_field(&conf->gen, &conf->gen.extra,
5648                                                                         newextra);
5649                                         conf->gen.source = source;
5650                                         conf->gen.scontext = context;
5651                                 }
5652
5653                                 if (makeDefault)
5654                                 {
5655                                         GucStack   *stack;
5656
5657                                         if (conf->gen.reset_source <= source)
5658                                         {
5659                                                 set_string_field(conf, &conf->reset_val, newval);
5660                                                 set_extra_field(&conf->gen, &conf->reset_extra,
5661                                                                                 newextra);
5662                                                 conf->gen.reset_source = source;
5663                                                 conf->gen.reset_scontext = context;
5664                                         }
5665                                         for (stack = conf->gen.stack; stack; stack = stack->prev)
5666                                         {
5667                                                 if (stack->source <= source)
5668                                                 {
5669                                                         set_string_field(conf, &stack->prior.val.stringval,
5670                                                                                          newval);
5671                                                         set_extra_field(&conf->gen, &stack->prior.extra,
5672                                                                                         newextra);
5673                                                         stack->source = source;
5674                                                         stack->scontext = context;
5675                                                 }
5676                                         }
5677                                 }
5678
5679                                 /* Perhaps we didn't install newval anywhere */
5680                                 if (newval && !string_field_used(conf, newval))
5681                                         free(newval);
5682                                 /* Perhaps we didn't install newextra anywhere */
5683                                 if (newextra && !extra_field_used(&conf->gen, newextra))
5684                                         free(newextra);
5685                                 break;
5686                         }
5687
5688                 case PGC_ENUM:
5689                         {
5690                                 struct config_enum *conf = (struct config_enum *) record;
5691                                 int                     newval;
5692                                 void       *newextra = NULL;
5693
5694                                 if (value)
5695                                 {
5696                                         if (!config_enum_lookup_by_name(conf, value, &newval))
5697                                         {
5698                                                 char       *hintmsg;
5699
5700                                                 hintmsg = config_enum_get_options(conf,
5701                                                                                                                 "Available values: ",
5702                                                                                                                   ".", ", ");
5703
5704                                                 ereport(elevel,
5705                                                                 (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
5706                                                  errmsg("invalid value for parameter \"%s\": \"%s\"",
5707                                                                 name, value),
5708                                                                  hintmsg ? errhint("%s", _(hintmsg)) : 0));
5709
5710                                                 if (hintmsg)
5711                                                         pfree(hintmsg);
5712                                                 return 0;
5713                                         }
5714                                         if (!call_enum_check_hook(conf, &newval, &newextra,
5715                                                                                           source, elevel))
5716                                                 return 0;
5717                                 }
5718                                 else if (source == PGC_S_DEFAULT)
5719                                 {
5720                                         newval = conf->boot_val;
5721                                         if (!call_enum_check_hook(conf, &newval, &newextra,
5722                                                                                           source, elevel))
5723                                                 return 0;
5724                                 }
5725                                 else
5726                                 {
5727                                         newval = conf->reset_val;
5728                                         newextra = conf->reset_extra;
5729                                         source = conf->gen.reset_source;
5730                                         context = conf->gen.reset_scontext;
5731                                 }
5732
5733                                 if (prohibitValueChange)
5734                                 {
5735                                         if (*conf->variable != newval)
5736                                         {
5737                                                 ereport(elevel,
5738                                                                 (errcode(ERRCODE_CANT_CHANGE_RUNTIME_PARAM),
5739                                                                  errmsg("parameter \"%s\" cannot be changed without restarting the server",
5740                                                                                 name)));
5741                                                 return 0;
5742                                         }
5743                                         return -1;
5744                                 }
5745
5746                                 if (changeVal)
5747                                 {
5748                                         /* Save old value to support transaction abort */
5749                                         if (!makeDefault)
5750                                                 push_old_value(&conf->gen, action);
5751
5752                                         if (conf->assign_hook)
5753                                                 (*conf->assign_hook) (newval, newextra);
5754                                         *conf->variable = newval;
5755                                         set_extra_field(&conf->gen, &conf->gen.extra,
5756                                                                         newextra);
5757                                         conf->gen.source = source;
5758                                         conf->gen.scontext = context;
5759                                 }
5760                                 if (makeDefault)
5761                                 {
5762                                         GucStack   *stack;
5763
5764                                         if (conf->gen.reset_source <= source)
5765                                         {
5766                                                 conf->reset_val = newval;
5767                                                 set_extra_field(&conf->gen, &conf->reset_extra,
5768                                                                                 newextra);
5769                                                 conf->gen.reset_source = source;
5770                                                 conf->gen.reset_scontext = context;
5771                                         }
5772                                         for (stack = conf->gen.stack; stack; stack = stack->prev)
5773                                         {
5774                                                 if (stack->source <= source)
5775                                                 {
5776                                                         stack->prior.val.enumval = newval;
5777                                                         set_extra_field(&conf->gen, &stack->prior.extra,
5778                                                                                         newextra);
5779                                                         stack->source = source;
5780                                                         stack->scontext = context;
5781                                                 }
5782                                         }
5783                                 }
5784
5785                                 /* Perhaps we didn't install newextra anywhere */
5786                                 if (newextra && !extra_field_used(&conf->gen, newextra))
5787                                         free(newextra);
5788                                 break;
5789                         }
5790         }
5791
5792         if (changeVal && (record->flags & GUC_REPORT))
5793                 ReportGUCOption(record);
5794
5795         return changeVal ? 1 : -1;
5796 }
5797
5798
5799 /*
5800  * Set the fields for source file and line number the setting came from.
5801  */
5802 static void
5803 set_config_sourcefile(const char *name, char *sourcefile, int sourceline)
5804 {
5805         struct config_generic *record;
5806         int                     elevel;
5807
5808         /*
5809          * To avoid cluttering the log, only the postmaster bleats loudly about
5810          * problems with the config file.
5811          */
5812         elevel = IsUnderPostmaster ? DEBUG3 : LOG;
5813
5814         record = find_option(name, true, elevel);
5815         /* should not happen */
5816         if (record == NULL)
5817                 elog(ERROR, "unrecognized configuration parameter \"%s\"", name);
5818
5819         sourcefile = guc_strdup(elevel, sourcefile);
5820         if (record->sourcefile)
5821                 free(record->sourcefile);
5822         record->sourcefile = sourcefile;
5823         record->sourceline = sourceline;
5824 }
5825
5826 /*
5827  * Set a config option to the given value.
5828  *
5829  * See also set_config_option; this is just the wrapper to be called from
5830  * outside GUC.  (This function should be used when possible, because its API
5831  * is more stable than set_config_option's.)
5832  *
5833  * Note: there is no support here for setting source file/line, as it
5834  * is currently not needed.
5835  */
5836 void
5837 SetConfigOption(const char *name, const char *value,
5838                                 GucContext context, GucSource source)
5839 {
5840         (void) set_config_option(name, value, context, source,
5841                                                          GUC_ACTION_SET, true, 0);
5842 }
5843
5844
5845
5846 /*
5847  * Fetch the current value of the option `name', as a string.
5848  *
5849  * If the option doesn't exist, return NULL if missing_ok is true (NOTE that
5850  * this cannot be distinguished from a string variable with a NULL value!),
5851  * otherwise throw an ereport and don't return.
5852  *
5853  * If restrict_superuser is true, we also enforce that only superusers can
5854  * see GUC_SUPERUSER_ONLY variables.  This should only be passed as true
5855  * in user-driven calls.
5856  *
5857  * The string is *not* allocated for modification and is really only
5858  * valid until the next call to configuration related functions.
5859  */
5860 const char *
5861 GetConfigOption(const char *name, bool missing_ok, bool restrict_superuser)
5862 {
5863         struct config_generic *record;
5864         static char buffer[256];
5865
5866         record = find_option(name, false, ERROR);
5867         if (record == NULL)
5868         {
5869                 if (missing_ok)
5870                         return NULL;
5871                 ereport(ERROR,
5872                                 (errcode(ERRCODE_UNDEFINED_OBJECT),
5873                                  errmsg("unrecognized configuration parameter \"%s\"",
5874                                                 name)));
5875         }
5876         if (restrict_superuser &&
5877                 (record->flags & GUC_SUPERUSER_ONLY) &&
5878                 !superuser())
5879                 ereport(ERROR,
5880                                 (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
5881                                  errmsg("must be superuser to examine \"%s\"", name)));
5882
5883         switch (record->vartype)
5884         {
5885                 case PGC_BOOL:
5886                         return *((struct config_bool *) record)->variable ? "on" : "off";
5887
5888                 case PGC_INT:
5889                         snprintf(buffer, sizeof(buffer), "%d",
5890                                          *((struct config_int *) record)->variable);
5891                         return buffer;
5892
5893                 case PGC_REAL:
5894                         snprintf(buffer, sizeof(buffer), "%g",
5895                                          *((struct config_real *) record)->variable);
5896                         return buffer;
5897
5898                 case PGC_STRING:
5899                         return *((struct config_string *) record)->variable;
5900
5901                 case PGC_ENUM:
5902                         return config_enum_lookup_by_value((struct config_enum *) record,
5903                                                                  *((struct config_enum *) record)->variable);
5904         }
5905         return NULL;
5906 }
5907
5908 /*
5909  * Get the RESET value associated with the given option.
5910  *
5911  * Note: this is not re-entrant, due to use of static result buffer;
5912  * not to mention that a string variable could have its reset_val changed.
5913  * Beware of assuming the result value is good for very long.
5914  */
5915 const char *
5916 GetConfigOptionResetString(const char *name)
5917 {
5918         struct config_generic *record;
5919         static char buffer[256];
5920
5921         record = find_option(name, false, ERROR);
5922         if (record == NULL)
5923                 ereport(ERROR,
5924                                 (errcode(ERRCODE_UNDEFINED_OBJECT),
5925                            errmsg("unrecognized configuration parameter \"%s\"", name)));
5926         if ((record->flags & GUC_SUPERUSER_ONLY) && !superuser())
5927                 ereport(ERROR,
5928                                 (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
5929                                  errmsg("must be superuser to examine \"%s\"", name)));
5930
5931         switch (record->vartype)
5932         {
5933                 case PGC_BOOL:
5934                         return ((struct config_bool *) record)->reset_val ? "on" : "off";
5935
5936                 case PGC_INT:
5937                         snprintf(buffer, sizeof(buffer), "%d",
5938                                          ((struct config_int *) record)->reset_val);
5939                         return buffer;
5940
5941                 case PGC_REAL:
5942                         snprintf(buffer, sizeof(buffer), "%g",
5943                                          ((struct config_real *) record)->reset_val);
5944                         return buffer;
5945
5946                 case PGC_STRING:
5947                         return ((struct config_string *) record)->reset_val;
5948
5949                 case PGC_ENUM:
5950                         return config_enum_lookup_by_value((struct config_enum *) record,
5951                                                                  ((struct config_enum *) record)->reset_val);
5952         }
5953         return NULL;
5954 }
5955
5956
5957 /*
5958  * flatten_set_variable_args
5959  *              Given a parsenode List as emitted by the grammar for SET,
5960  *              convert to the flat string representation used by GUC.
5961  *
5962  * We need to be told the name of the variable the args are for, because
5963  * the flattening rules vary (ugh).
5964  *
5965  * The result is NULL if args is NIL (ie, SET ... TO DEFAULT), otherwise
5966  * a palloc'd string.
5967  */
5968 static char *
5969 flatten_set_variable_args(const char *name, List *args)
5970 {
5971         struct config_generic *record;
5972         int                     flags;
5973         StringInfoData buf;
5974         ListCell   *l;
5975
5976         /* Fast path if just DEFAULT */
5977         if (args == NIL)
5978                 return NULL;
5979
5980         /*
5981          * Get flags for the variable; if it's not known, use default flags.
5982          * (Caller might throw error later, but not our business to do so here.)
5983          */
5984         record = find_option(name, false, WARNING);
5985         if (record)
5986                 flags = record->flags;
5987         else
5988                 flags = 0;
5989
5990         /* Complain if list input and non-list variable */
5991         if ((flags & GUC_LIST_INPUT) == 0 &&
5992                 list_length(args) != 1)
5993                 ereport(ERROR,
5994                                 (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
5995                                  errmsg("SET %s takes only one argument", name)));
5996
5997         initStringInfo(&buf);
5998
5999         /*
6000          * Each list member may be a plain A_Const node, or an A_Const within a
6001          * TypeCast; the latter case is supported only for ConstInterval arguments
6002          * (for SET TIME ZONE).
6003          */
6004         foreach(l, args)
6005         {
6006                 Node       *arg = (Node *) lfirst(l);
6007                 char       *val;
6008                 TypeName   *typeName = NULL;
6009                 A_Const    *con;
6010
6011                 if (l != list_head(args))
6012                         appendStringInfo(&buf, ", ");
6013
6014                 if (IsA(arg, TypeCast))
6015                 {
6016                         TypeCast   *tc = (TypeCast *) arg;
6017
6018                         arg = tc->arg;
6019                         typeName = tc->typeName;
6020                 }
6021
6022                 if (!IsA(arg, A_Const))
6023                         elog(ERROR, "unrecognized node type: %d", (int) nodeTag(arg));
6024                 con = (A_Const *) arg;
6025
6026                 switch (nodeTag(&con->val))
6027                 {
6028                         case T_Integer:
6029                                 appendStringInfo(&buf, "%ld", intVal(&con->val));
6030                                 break;
6031                         case T_Float:
6032                                 /* represented as a string, so just copy it */
6033                                 appendStringInfoString(&buf, strVal(&con->val));
6034                                 break;
6035                         case T_String:
6036                                 val = strVal(&con->val);
6037                                 if (typeName != NULL)
6038                                 {
6039                                         /*
6040                                          * Must be a ConstInterval argument for TIME ZONE. Coerce
6041                                          * to interval and back to normalize the value and account
6042                                          * for any typmod.
6043                                          */
6044                                         Oid                     typoid;
6045                                         int32           typmod;
6046                                         Datum           interval;
6047                                         char       *intervalout;
6048
6049                                         typenameTypeIdAndMod(NULL, typeName, &typoid, &typmod);
6050                                         Assert(typoid == INTERVALOID);
6051
6052                                         interval =
6053                                                 DirectFunctionCall3(interval_in,
6054                                                                                         CStringGetDatum(val),
6055                                                                                         ObjectIdGetDatum(InvalidOid),
6056                                                                                         Int32GetDatum(typmod));
6057
6058                                         intervalout =
6059                                                 DatumGetCString(DirectFunctionCall1(interval_out,
6060                                                                                                                         interval));
6061                                         appendStringInfo(&buf, "INTERVAL '%s'", intervalout);
6062                                 }
6063                                 else
6064                                 {
6065                                         /*
6066                                          * Plain string literal or identifier.  For quote mode,
6067                                          * quote it if it's not a vanilla identifier.
6068                                          */
6069                                         if (flags & GUC_LIST_QUOTE)
6070                                                 appendStringInfoString(&buf, quote_identifier(val));
6071                                         else
6072                                                 appendStringInfoString(&buf, val);
6073                                 }
6074                                 break;
6075                         default:
6076                                 elog(ERROR, "unrecognized node type: %d",
6077                                          (int) nodeTag(&con->val));
6078                                 break;
6079                 }
6080         }
6081
6082         return buf.data;
6083 }
6084
6085
6086 /*
6087  * SET command
6088  */
6089 void
6090 ExecSetVariableStmt(VariableSetStmt *stmt)
6091 {
6092         GucAction       action = stmt->is_local ? GUC_ACTION_LOCAL : GUC_ACTION_SET;
6093
6094         switch (stmt->kind)
6095         {
6096                 case VAR_SET_VALUE:
6097                 case VAR_SET_CURRENT:
6098                         (void) set_config_option(stmt->name,
6099                                                                          ExtractSetVariableArgs(stmt),
6100                                                                          (superuser() ? PGC_SUSET : PGC_USERSET),
6101                                                                          PGC_S_SESSION,
6102                                                                          action,
6103                                                                          true,
6104                                                                          0);
6105                         break;
6106                 case VAR_SET_MULTI:
6107
6108                         /*
6109                          * Special-case SQL syntaxes.  The TRANSACTION and SESSION
6110                          * CHARACTERISTICS cases effectively set more than one variable
6111                          * per statement.  TRANSACTION SNAPSHOT only takes one argument,
6112                          * but we put it here anyway since it's a special case and not
6113                          * related to any GUC variable.
6114                          */
6115                         if (strcmp(stmt->name, "TRANSACTION") == 0)
6116                         {
6117                                 ListCell   *head;
6118
6119                                 foreach(head, stmt->args)
6120                                 {
6121                                         DefElem    *item = (DefElem *) lfirst(head);
6122
6123                                         if (strcmp(item->defname, "transaction_isolation") == 0)
6124                                                 SetPGVariable("transaction_isolation",
6125                                                                           list_make1(item->arg), stmt->is_local);
6126                                         else if (strcmp(item->defname, "transaction_read_only") == 0)
6127                                                 SetPGVariable("transaction_read_only",
6128                                                                           list_make1(item->arg), stmt->is_local);
6129                                         else if (strcmp(item->defname, "transaction_deferrable") == 0)
6130                                                 SetPGVariable("transaction_deferrable",
6131                                                                           list_make1(item->arg), stmt->is_local);
6132                                         else
6133                                                 elog(ERROR, "unexpected SET TRANSACTION element: %s",
6134                                                          item->defname);
6135                                 }
6136                         }
6137                         else if (strcmp(stmt->name, "SESSION CHARACTERISTICS") == 0)
6138                         {
6139                                 ListCell   *head;
6140
6141                                 foreach(head, stmt->args)
6142                                 {
6143                                         DefElem    *item = (DefElem *) lfirst(head);
6144
6145                                         if (strcmp(item->defname, "transaction_isolation") == 0)
6146                                                 SetPGVariable("default_transaction_isolation",
6147                                                                           list_make1(item->arg), stmt->is_local);
6148                                         else if (strcmp(item->defname, "transaction_read_only") == 0)
6149                                                 SetPGVariable("default_transaction_read_only",
6150                                                                           list_make1(item->arg), stmt->is_local);
6151                                         else if (strcmp(item->defname, "transaction_deferrable") == 0)
6152                                                 SetPGVariable("default_transaction_deferrable",
6153                                                                           list_make1(item->arg), stmt->is_local);
6154                                         else
6155                                                 elog(ERROR, "unexpected SET SESSION element: %s",
6156                                                          item->defname);
6157                                 }
6158                         }
6159                         else if (strcmp(stmt->name, "TRANSACTION SNAPSHOT") == 0)
6160                         {
6161                                 A_Const    *con = (A_Const *) linitial(stmt->args);
6162
6163                                 if (stmt->is_local)
6164                                         ereport(ERROR,
6165                                                         (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
6166                                                          errmsg("SET LOCAL TRANSACTION SNAPSHOT is not implemented")));
6167                                 Assert(IsA(con, A_Const));
6168                                 Assert(nodeTag(&con->val) == T_String);
6169                                 ImportSnapshot(strVal(&con->val));
6170                         }
6171                         else
6172                                 elog(ERROR, "unexpected SET MULTI element: %s",
6173                                          stmt->name);
6174                         break;
6175                 case VAR_SET_DEFAULT:
6176                 case VAR_RESET:
6177                         (void) set_config_option(stmt->name,
6178                                                                          NULL,
6179                                                                          (superuser() ? PGC_SUSET : PGC_USERSET),
6180                                                                          PGC_S_SESSION,
6181                                                                          action,
6182                                                                          true,
6183                                                                          0);
6184                         break;
6185                 case VAR_RESET_ALL:
6186                         ResetAllOptions();
6187                         break;
6188         }
6189 }
6190
6191 /*
6192  * Get the value to assign for a VariableSetStmt, or NULL if it's RESET.
6193  * The result is palloc'd.
6194  *
6195  * This is exported for use by actions such as ALTER ROLE SET.
6196  */
6197 char *
6198 ExtractSetVariableArgs(VariableSetStmt *stmt)
6199 {
6200         switch (stmt->kind)
6201         {
6202                 case VAR_SET_VALUE:
6203                         return flatten_set_variable_args(stmt->name, stmt->args);
6204                 case VAR_SET_CURRENT:
6205                         return GetConfigOptionByName(stmt->name, NULL);
6206                 default:
6207                         return NULL;
6208         }
6209 }
6210
6211 /*
6212  * SetPGVariable - SET command exported as an easily-C-callable function.
6213  *
6214  * This provides access to SET TO value, as well as SET TO DEFAULT (expressed
6215  * by passing args == NIL), but not SET FROM CURRENT functionality.
6216  */
6217 void
6218 SetPGVariable(const char *name, List *args, bool is_local)
6219 {
6220         char       *argstring = flatten_set_variable_args(name, args);
6221
6222         /* Note SET DEFAULT (argstring == NULL) is equivalent to RESET */
6223         (void) set_config_option(name,
6224                                                          argstring,
6225                                                          (superuser() ? PGC_SUSET : PGC_USERSET),
6226                                                          PGC_S_SESSION,
6227                                                          is_local ? GUC_ACTION_LOCAL : GUC_ACTION_SET,
6228                                                          true,
6229                                                          0);
6230 }
6231
6232 /*
6233  * SET command wrapped as a SQL callable function.
6234  */
6235 Datum
6236 set_config_by_name(PG_FUNCTION_ARGS)
6237 {
6238         char       *name;
6239         char       *value;
6240         char       *new_value;
6241         bool            is_local;
6242
6243         if (PG_ARGISNULL(0))
6244                 ereport(ERROR,
6245                                 (errcode(ERRCODE_NULL_VALUE_NOT_ALLOWED),
6246                                  errmsg("SET requires parameter name")));
6247
6248         /* Get the GUC variable name */
6249         name = TextDatumGetCString(PG_GETARG_DATUM(0));
6250
6251         /* Get the desired value or set to NULL for a reset request */
6252         if (PG_ARGISNULL(1))
6253                 value = NULL;
6254         else
6255                 value = TextDatumGetCString(PG_GETARG_DATUM(1));
6256
6257         /*
6258          * Get the desired state of is_local. Default to false if provided value
6259          * is NULL
6260          */
6261         if (PG_ARGISNULL(2))
6262                 is_local = false;
6263         else
6264                 is_local = PG_GETARG_BOOL(2);
6265
6266         /* Note SET DEFAULT (argstring == NULL) is equivalent to RESET */
6267         (void) set_config_option(name,
6268                                                          value,
6269                                                          (superuser() ? PGC_SUSET : PGC_USERSET),
6270                                                          PGC_S_SESSION,
6271                                                          is_local ? GUC_ACTION_LOCAL : GUC_ACTION_SET,
6272                                                          true,
6273                                                          0);
6274
6275         /* get the new current value */
6276         new_value = GetConfigOptionByName(name, NULL);
6277
6278         /* Convert return string to text */
6279         PG_RETURN_TEXT_P(cstring_to_text(new_value));
6280 }
6281
6282
6283 /*
6284  * Common code for DefineCustomXXXVariable subroutines: allocate the
6285  * new variable's config struct and fill in generic fields.
6286  */
6287 static struct config_generic *
6288 init_custom_variable(const char *name,
6289                                          const char *short_desc,
6290                                          const char *long_desc,
6291                                          GucContext context,
6292                                          int flags,
6293                                          enum config_type type,
6294                                          size_t sz)
6295 {
6296         struct config_generic *gen;
6297
6298         /*
6299          * Only allow custom PGC_POSTMASTER variables to be created during shared
6300          * library preload; any later than that, we can't ensure that the value
6301          * doesn't change after startup.  This is a fatal elog if it happens; just
6302          * erroring out isn't safe because we don't know what the calling loadable
6303          * module might already have hooked into.
6304          */
6305         if (context == PGC_POSTMASTER &&
6306                 !process_shared_preload_libraries_in_progress)
6307                 elog(FATAL, "cannot create PGC_POSTMASTER variables after startup");
6308
6309         gen = (struct config_generic *) guc_malloc(ERROR, sz);
6310         memset(gen, 0, sz);
6311
6312         gen->name = guc_strdup(ERROR, name);
6313         gen->context = context;
6314         gen->group = CUSTOM_OPTIONS;
6315         gen->short_desc = short_desc;
6316         gen->long_desc = long_desc;
6317         gen->flags = flags;
6318         gen->vartype = type;
6319
6320         return gen;
6321 }
6322
6323 /*
6324  * Common code for DefineCustomXXXVariable subroutines: insert the new
6325  * variable into the GUC variable array, replacing any placeholder.
6326  */
6327 static void
6328 define_custom_variable(struct config_generic * variable)
6329 {
6330         const char *name = variable->name;
6331         const char **nameAddr = &name;
6332         struct config_string *pHolder;
6333         struct config_generic **res;
6334
6335         /*
6336          * See if there's a placeholder by the same name.
6337          */
6338         res = (struct config_generic **) bsearch((void *) &nameAddr,
6339                                                                                          (void *) guc_variables,
6340                                                                                          num_guc_variables,
6341                                                                                          sizeof(struct config_generic *),
6342                                                                                          guc_var_compare);
6343         if (res == NULL)
6344         {
6345                 /*
6346                  * No placeholder to replace, so we can just add it ... but first,
6347                  * make sure it's initialized to its default value.
6348                  */
6349                 InitializeOneGUCOption(variable);
6350                 add_guc_variable(variable, ERROR);
6351                 return;
6352         }
6353
6354         /*
6355          * This better be a placeholder
6356          */
6357         if (((*res)->flags & GUC_CUSTOM_PLACEHOLDER) == 0)
6358                 ereport(ERROR,
6359                                 (errcode(ERRCODE_INTERNAL_ERROR),
6360                                  errmsg("attempt to redefine parameter \"%s\"", name)));
6361
6362         Assert((*res)->vartype == PGC_STRING);
6363         pHolder = (struct config_string *) (*res);
6364
6365         /*
6366          * First, set the variable to its default value.  We must do this even
6367          * though we intend to immediately apply a new value, since it's possible
6368          * that the new value is invalid.
6369          */
6370         InitializeOneGUCOption(variable);
6371
6372         /*
6373          * Replace the placeholder. We aren't changing the name, so no re-sorting
6374          * is necessary
6375          */
6376         *res = variable;
6377
6378         /*
6379          * Assign the string value(s) stored in the placeholder to the real
6380          * variable.  Essentially, we need to duplicate all the active and stacked
6381          * values, but with appropriate validation and datatype adjustment.
6382          *
6383          * If an assignment fails, we report a WARNING and keep going.  We don't
6384          * want to throw ERROR for bad values, because it'd bollix the add-on
6385          * module that's presumably halfway through getting loaded.  In such cases
6386          * the default or previous state will become active instead.
6387          */
6388
6389         /* First, apply the reset value if any */
6390         if (pHolder->reset_val)
6391                 (void) set_config_option(name, pHolder->reset_val,
6392                                                                  pHolder->gen.reset_scontext,
6393                                                                  pHolder->gen.reset_source,
6394                                                                  GUC_ACTION_SET, true, WARNING);
6395         /* That should not have resulted in stacking anything */
6396         Assert(variable->stack == NULL);
6397
6398         /* Now, apply current and stacked values, in the order they were stacked */
6399         reapply_stacked_values(variable, pHolder, pHolder->gen.stack,
6400                                                    *(pHolder->variable),
6401                                                    pHolder->gen.scontext, pHolder->gen.source);
6402
6403         /* Also copy over any saved source-location information */
6404         if (pHolder->gen.sourcefile)
6405                 set_config_sourcefile(name, pHolder->gen.sourcefile,
6406                                                           pHolder->gen.sourceline);
6407
6408         /*
6409          * Free up as much as we conveniently can of the placeholder structure.
6410          * (This neglects any stack items, so it's possible for some memory to be
6411          * leaked.  Since this can only happen once per session per variable, it
6412          * doesn't seem worth spending much code on.)
6413          */
6414         set_string_field(pHolder, pHolder->variable, NULL);
6415         set_string_field(pHolder, &pHolder->reset_val, NULL);
6416
6417         free(pHolder);
6418 }
6419
6420 /*
6421  * Recursive subroutine for define_custom_variable: reapply non-reset values
6422  *
6423  * We recurse so that the values are applied in the same order as originally.
6424  * At each recursion level, apply the upper-level value (passed in) in the
6425  * fashion implied by the stack entry.
6426  */
6427 static void
6428 reapply_stacked_values(struct config_generic * variable,
6429                                            struct config_string *pHolder,
6430                                            GucStack *stack,
6431                                            const char *curvalue,
6432                                            GucContext curscontext, GucSource cursource)
6433 {
6434         const char *name = variable->name;
6435         GucStack   *oldvarstack = variable->stack;
6436
6437         if (stack != NULL)
6438         {
6439                 /* First, recurse, so that stack items are processed bottom to top */
6440                 reapply_stacked_values(variable, pHolder, stack->prev,
6441                                                            stack->prior.val.stringval,
6442                                                            stack->scontext, stack->source);
6443
6444                 /* See how to apply the passed-in value */
6445                 switch (stack->state)
6446                 {
6447                         case GUC_SAVE:
6448                                 (void) set_config_option(name, curvalue,
6449                                                                                  curscontext, cursource,
6450                                                                                  GUC_ACTION_SAVE, true, WARNING);
6451                                 break;
6452
6453                         case GUC_SET:
6454                                 (void) set_config_option(name, curvalue,
6455                                                                                  curscontext, cursource,
6456                                                                                  GUC_ACTION_SET, true, WARNING);
6457                                 break;
6458
6459                         case GUC_LOCAL:
6460                                 (void) set_config_option(name, curvalue,
6461                                                                                  curscontext, cursource,
6462                                                                                  GUC_ACTION_LOCAL, true, WARNING);
6463                                 break;
6464
6465                         case GUC_SET_LOCAL:
6466                                 /* first, apply the masked value as SET */
6467                                 (void) set_config_option(name, stack->masked.val.stringval,
6468                                                                                  stack->masked_scontext, PGC_S_SESSION,
6469                                                                                  GUC_ACTION_SET, true, WARNING);
6470                                 /* then apply the current value as LOCAL */
6471                                 (void) set_config_option(name, curvalue,
6472                                                                                  curscontext, cursource,
6473                                                                                  GUC_ACTION_LOCAL, true, WARNING);
6474                                 break;
6475                 }
6476
6477                 /* If we successfully made a stack entry, adjust its nest level */
6478                 if (variable->stack != oldvarstack)
6479                         variable->stack->nest_level = stack->nest_level;
6480         }
6481         else
6482         {
6483                 /*
6484                  * We are at the end of the stack.  If the active/previous value is
6485                  * different from the reset value, it must represent a previously
6486                  * committed session value.  Apply it, and then drop the stack entry
6487                  * that set_config_option will have created under the impression that
6488                  * this is to be just a transactional assignment.  (We leak the stack
6489                  * entry.)
6490                  */
6491                 if (curvalue != pHolder->reset_val ||
6492                         curscontext != pHolder->gen.reset_scontext ||
6493                         cursource != pHolder->gen.reset_source)
6494                 {
6495                         (void) set_config_option(name, curvalue,
6496                                                                          curscontext, cursource,
6497                                                                          GUC_ACTION_SET, true, WARNING);
6498                         variable->stack = NULL;
6499                 }
6500         }
6501 }
6502
6503 void
6504 DefineCustomBoolVariable(const char *name,
6505                                                  const char *short_desc,
6506                                                  const char *long_desc,
6507                                                  bool *valueAddr,
6508                                                  bool bootValue,
6509                                                  GucContext context,
6510                                                  int flags,
6511                                                  GucBoolCheckHook check_hook,
6512                                                  GucBoolAssignHook assign_hook,
6513                                                  GucShowHook show_hook)
6514 {
6515         struct config_bool *var;
6516
6517         var = (struct config_bool *)
6518                 init_custom_variable(name, short_desc, long_desc, context, flags,
6519                                                          PGC_BOOL, sizeof(struct config_bool));
6520         var->variable = valueAddr;
6521         var->boot_val = bootValue;
6522         var->reset_val = bootValue;
6523         var->check_hook = check_hook;
6524         var->assign_hook = assign_hook;
6525         var->show_hook = show_hook;
6526         define_custom_variable(&var->gen);
6527 }
6528
6529 void
6530 DefineCustomIntVariable(const char *name,
6531                                                 const char *short_desc,
6532                                                 const char *long_desc,
6533                                                 int *valueAddr,
6534                                                 int bootValue,
6535                                                 int minValue,
6536                                                 int maxValue,
6537                                                 GucContext context,
6538                                                 int flags,
6539                                                 GucIntCheckHook check_hook,
6540                                                 GucIntAssignHook assign_hook,
6541                                                 GucShowHook show_hook)
6542 {
6543         struct config_int *var;
6544
6545         var = (struct config_int *)
6546                 init_custom_variable(name, short_desc, long_desc, context, flags,
6547                                                          PGC_INT, sizeof(struct config_int));
6548         var->variable = valueAddr;
6549         var->boot_val = bootValue;
6550         var->reset_val = bootValue;
6551         var->min = minValue;
6552         var->max = maxValue;
6553         var->check_hook = check_hook;
6554         var->assign_hook = assign_hook;
6555         var->show_hook = show_hook;
6556         define_custom_variable(&var->gen);
6557 }
6558
6559 void
6560 DefineCustomRealVariable(const char *name,
6561                                                  const char *short_desc,
6562                                                  const char *long_desc,
6563                                                  double *valueAddr,
6564                                                  double bootValue,
6565                                                  double minValue,
6566                                                  double maxValue,
6567                                                  GucContext context,
6568                                                  int flags,
6569                                                  GucRealCheckHook check_hook,
6570                                                  GucRealAssignHook assign_hook,
6571                                                  GucShowHook show_hook)
6572 {
6573         struct config_real *var;
6574
6575         var = (struct config_real *)
6576                 init_custom_variable(name, short_desc, long_desc, context, flags,
6577                                                          PGC_REAL, sizeof(struct config_real));
6578         var->variable = valueAddr;
6579         var->boot_val = bootValue;
6580         var->reset_val = bootValue;
6581         var->min = minValue;
6582         var->max = maxValue;
6583         var->check_hook = check_hook;
6584         var->assign_hook = assign_hook;
6585         var->show_hook = show_hook;
6586         define_custom_variable(&var->gen);
6587 }
6588
6589 void
6590 DefineCustomStringVariable(const char *name,
6591                                                    const char *short_desc,
6592                                                    const char *long_desc,
6593                                                    char **valueAddr,
6594                                                    const char *bootValue,
6595                                                    GucContext context,
6596                                                    int flags,
6597                                                    GucStringCheckHook check_hook,
6598                                                    GucStringAssignHook assign_hook,
6599                                                    GucShowHook show_hook)
6600 {
6601         struct config_string *var;
6602
6603         var = (struct config_string *)
6604                 init_custom_variable(name, short_desc, long_desc, context, flags,
6605                                                          PGC_STRING, sizeof(struct config_string));
6606         var->variable = valueAddr;
6607         var->boot_val = bootValue;
6608         var->check_hook = check_hook;
6609         var->assign_hook = assign_hook;
6610         var->show_hook = show_hook;
6611         define_custom_variable(&var->gen);
6612 }
6613
6614 void
6615 DefineCustomEnumVariable(const char *name,
6616                                                  const char *short_desc,
6617                                                  const char *long_desc,
6618                                                  int *valueAddr,
6619                                                  int bootValue,
6620                                                  const struct config_enum_entry * options,
6621                                                  GucContext context,
6622                                                  int flags,
6623                                                  GucEnumCheckHook check_hook,
6624                                                  GucEnumAssignHook assign_hook,
6625                                                  GucShowHook show_hook)
6626 {
6627         struct config_enum *var;
6628
6629         var = (struct config_enum *)
6630                 init_custom_variable(name, short_desc, long_desc, context, flags,
6631                                                          PGC_ENUM, sizeof(struct config_enum));
6632         var->variable = valueAddr;
6633         var->boot_val = bootValue;
6634         var->reset_val = bootValue;
6635         var->options = options;
6636         var->check_hook = check_hook;
6637         var->assign_hook = assign_hook;
6638         var->show_hook = show_hook;
6639         define_custom_variable(&var->gen);
6640 }
6641
6642 void
6643 EmitWarningsOnPlaceholders(const char *className)
6644 {
6645         int                     classLen = strlen(className);
6646         int                     i;
6647
6648         for (i = 0; i < num_guc_variables; i++)
6649         {
6650                 struct config_generic *var = guc_variables[i];
6651
6652                 if ((var->flags & GUC_CUSTOM_PLACEHOLDER) != 0 &&
6653                         strncmp(className, var->name, classLen) == 0 &&
6654                         var->name[classLen] == GUC_QUALIFIER_SEPARATOR)
6655                 {
6656                         ereport(WARNING,
6657                                         (errcode(ERRCODE_UNDEFINED_OBJECT),
6658                                          errmsg("unrecognized configuration parameter \"%s\"",
6659                                                         var->name)));
6660                 }
6661         }
6662 }
6663
6664
6665 /*
6666  * SHOW command
6667  */
6668 void
6669 GetPGVariable(const char *name, DestReceiver *dest)
6670 {
6671         if (guc_name_compare(name, "all") == 0)
6672                 ShowAllGUCConfig(dest);
6673         else
6674                 ShowGUCConfigOption(name, dest);
6675 }
6676
6677 TupleDesc
6678 GetPGVariableResultDesc(const char *name)
6679 {
6680         TupleDesc       tupdesc;
6681
6682         if (guc_name_compare(name, "all") == 0)
6683         {
6684                 /* need a tuple descriptor representing three TEXT columns */
6685                 tupdesc = CreateTemplateTupleDesc(3, false);
6686                 TupleDescInitEntry(tupdesc, (AttrNumber) 1, "name",
6687                                                    TEXTOID, -1, 0);
6688                 TupleDescInitEntry(tupdesc, (AttrNumber) 2, "setting",
6689                                                    TEXTOID, -1, 0);
6690                 TupleDescInitEntry(tupdesc, (AttrNumber) 3, "description",
6691                                                    TEXTOID, -1, 0);
6692         }
6693         else
6694         {
6695                 const char *varname;
6696
6697                 /* Get the canonical spelling of name */
6698                 (void) GetConfigOptionByName(name, &varname);
6699
6700                 /* need a tuple descriptor representing a single TEXT column */
6701                 tupdesc = CreateTemplateTupleDesc(1, false);
6702                 TupleDescInitEntry(tupdesc, (AttrNumber) 1, varname,
6703                                                    TEXTOID, -1, 0);
6704         }
6705         return tupdesc;
6706 }
6707
6708
6709 /*
6710  * SHOW command
6711  */
6712 static void
6713 ShowGUCConfigOption(const char *name, DestReceiver *dest)
6714 {
6715         TupOutputState *tstate;
6716         TupleDesc       tupdesc;
6717         const char *varname;
6718         char       *value;
6719
6720         /* Get the value and canonical spelling of name */
6721         value = GetConfigOptionByName(name, &varname);
6722
6723         /* need a tuple descriptor representing a single TEXT column */
6724         tupdesc = CreateTemplateTupleDesc(1, false);
6725         TupleDescInitEntry(tupdesc, (AttrNumber) 1, varname,
6726                                            TEXTOID, -1, 0);
6727
6728         /* prepare for projection of tuples */
6729         tstate = begin_tup_output_tupdesc(dest, tupdesc);
6730
6731         /* Send it */
6732         do_text_output_oneline(tstate, value);
6733
6734         end_tup_output(tstate);
6735 }
6736
6737 /*
6738  * SHOW ALL command
6739  */
6740 static void
6741 ShowAllGUCConfig(DestReceiver *dest)
6742 {
6743         bool            am_superuser = superuser();
6744         int                     i;
6745         TupOutputState *tstate;
6746         TupleDesc       tupdesc;
6747         Datum           values[3];
6748         bool            isnull[3] = {false, false, false};
6749
6750         /* need a tuple descriptor representing three TEXT columns */
6751         tupdesc = CreateTemplateTupleDesc(3, false);
6752         TupleDescInitEntry(tupdesc, (AttrNumber) 1, "name",
6753                                            TEXTOID, -1, 0);
6754         TupleDescInitEntry(tupdesc, (AttrNumber) 2, "setting",
6755                                            TEXTOID, -1, 0);
6756         TupleDescInitEntry(tupdesc, (AttrNumber) 3, "description",
6757                                            TEXTOID, -1, 0);
6758
6759         /* prepare for projection of tuples */
6760         tstate = begin_tup_output_tupdesc(dest, tupdesc);
6761
6762         for (i = 0; i < num_guc_variables; i++)
6763         {
6764                 struct config_generic *conf = guc_variables[i];
6765                 char       *setting;
6766
6767                 if ((conf->flags & GUC_NO_SHOW_ALL) ||
6768                         ((conf->flags & GUC_SUPERUSER_ONLY) && !am_superuser))
6769                         continue;
6770
6771                 /* assign to the values array */
6772                 values[0] = PointerGetDatum(cstring_to_text(conf->name));
6773
6774                 setting = _ShowOption(conf, true);
6775                 if (setting)
6776                 {
6777                         values[1] = PointerGetDatum(cstring_to_text(setting));
6778                         isnull[1] = false;
6779                 }
6780                 else
6781                 {
6782                         values[1] = PointerGetDatum(NULL);
6783                         isnull[1] = true;
6784                 }
6785
6786                 values[2] = PointerGetDatum(cstring_to_text(conf->short_desc));
6787
6788                 /* send it to dest */
6789                 do_tup_output(tstate, values, isnull);
6790
6791                 /* clean up */
6792                 pfree(DatumGetPointer(values[0]));
6793                 if (setting)
6794                 {
6795                         pfree(setting);
6796                         pfree(DatumGetPointer(values[1]));
6797                 }
6798                 pfree(DatumGetPointer(values[2]));
6799         }
6800
6801         end_tup_output(tstate);
6802 }
6803
6804 /*
6805  * Return GUC variable value by name; optionally return canonical
6806  * form of name.  Return value is palloc'd.
6807  */
6808 char *
6809 GetConfigOptionByName(const char *name, const char **varname)
6810 {
6811         struct config_generic *record;
6812
6813         record = find_option(name, false, ERROR);
6814         if (record == NULL)
6815                 ereport(ERROR,
6816                                 (errcode(ERRCODE_UNDEFINED_OBJECT),
6817                            errmsg("unrecognized configuration parameter \"%s\"", name)));
6818         if ((record->flags & GUC_SUPERUSER_ONLY) && !superuser())
6819                 ereport(ERROR,
6820                                 (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
6821                                  errmsg("must be superuser to examine \"%s\"", name)));
6822
6823         if (varname)
6824                 *varname = record->name;
6825
6826         return _ShowOption(record, true);
6827 }
6828
6829 /*
6830  * Return GUC variable value by variable number; optionally return canonical
6831  * form of name.  Return value is palloc'd.
6832  */
6833 void
6834 GetConfigOptionByNum(int varnum, const char **values, bool *noshow)
6835 {
6836         char            buffer[256];
6837         struct config_generic *conf;
6838
6839         /* check requested variable number valid */
6840         Assert((varnum >= 0) && (varnum < num_guc_variables));
6841
6842         conf = guc_variables[varnum];
6843
6844         if (noshow)
6845         {
6846                 if ((conf->flags & GUC_NO_SHOW_ALL) ||
6847                         ((conf->flags & GUC_SUPERUSER_ONLY) && !superuser()))
6848                         *noshow = true;
6849                 else
6850                         *noshow = false;
6851         }
6852
6853         /* first get the generic attributes */
6854
6855         /* name */
6856         values[0] = conf->name;
6857
6858         /* setting : use _ShowOption in order to avoid duplicating the logic */
6859         values[1] = _ShowOption(conf, false);
6860
6861         /* unit */
6862         if (conf->vartype == PGC_INT)
6863         {
6864                 static char buf[8];
6865
6866                 switch (conf->flags & (GUC_UNIT_MEMORY | GUC_UNIT_TIME))
6867                 {
6868                         case GUC_UNIT_KB:
6869                                 values[2] = "kB";
6870                                 break;
6871                         case GUC_UNIT_BLOCKS:
6872                                 snprintf(buf, sizeof(buf), "%dkB", BLCKSZ / 1024);
6873                                 values[2] = buf;
6874                                 break;
6875                         case GUC_UNIT_XBLOCKS:
6876                                 snprintf(buf, sizeof(buf), "%dkB", XLOG_BLCKSZ / 1024);
6877                                 values[2] = buf;
6878                                 break;
6879                         case GUC_UNIT_MS:
6880                                 values[2] = "ms";
6881                                 break;
6882                         case GUC_UNIT_S:
6883                                 values[2] = "s";
6884                                 break;
6885                         case GUC_UNIT_MIN:
6886                                 values[2] = "min";
6887                                 break;
6888                         default:
6889                                 values[2] = "";
6890                                 break;
6891                 }
6892         }
6893         else
6894                 values[2] = NULL;
6895
6896         /* group */
6897         values[3] = config_group_names[conf->group];
6898
6899         /* short_desc */
6900         values[4] = conf->short_desc;
6901
6902         /* extra_desc */
6903         values[5] = conf->long_desc;
6904
6905         /* context */
6906         values[6] = GucContext_Names[conf->context];
6907
6908         /* vartype */
6909         values[7] = config_type_names[conf->vartype];
6910
6911         /* source */
6912         values[8] = GucSource_Names[conf->source];
6913
6914         /* now get the type specifc attributes */
6915         switch (conf->vartype)
6916         {
6917                 case PGC_BOOL:
6918                         {
6919                                 struct config_bool *lconf = (struct config_bool *) conf;
6920
6921                                 /* min_val */
6922                                 values[9] = NULL;
6923
6924                                 /* max_val */
6925                                 values[10] = NULL;
6926
6927                                 /* enumvals */
6928                                 values[11] = NULL;
6929
6930                                 /* boot_val */
6931                                 values[12] = pstrdup(lconf->boot_val ? "on" : "off");
6932
6933                                 /* reset_val */
6934                                 values[13] = pstrdup(lconf->reset_val ? "on" : "off");
6935                         }
6936                         break;
6937
6938                 case PGC_INT:
6939                         {
6940                                 struct config_int *lconf = (struct config_int *) conf;
6941
6942                                 /* min_val */
6943                                 snprintf(buffer, sizeof(buffer), "%d", lconf->min);
6944                                 values[9] = pstrdup(buffer);
6945
6946                                 /* max_val */
6947                                 snprintf(buffer, sizeof(buffer), "%d", lconf->max);
6948                                 values[10] = pstrdup(buffer);
6949
6950                                 /* enumvals */
6951                                 values[11] = NULL;
6952
6953                                 /* boot_val */
6954                                 snprintf(buffer, sizeof(buffer), "%d", lconf->boot_val);
6955                                 values[12] = pstrdup(buffer);
6956
6957                                 /* reset_val */
6958                                 snprintf(buffer, sizeof(buffer), "%d", lconf->reset_val);
6959                                 values[13] = pstrdup(buffer);
6960                         }
6961                         break;
6962
6963                 case PGC_REAL:
6964                         {
6965                                 struct config_real *lconf = (struct config_real *) conf;
6966
6967                                 /* min_val */
6968                                 snprintf(buffer, sizeof(buffer), "%g", lconf->min);
6969                                 values[9] = pstrdup(buffer);
6970
6971                                 /* max_val */
6972                                 snprintf(buffer, sizeof(buffer), "%g", lconf->max);
6973                                 values[10] = pstrdup(buffer);
6974
6975                                 /* enumvals */
6976                                 values[11] = NULL;
6977
6978                                 /* boot_val */
6979                                 snprintf(buffer, sizeof(buffer), "%g", lconf->boot_val);
6980                                 values[12] = pstrdup(buffer);
6981
6982                                 /* reset_val */
6983                                 snprintf(buffer, sizeof(buffer), "%g", lconf->reset_val);
6984                                 values[13] = pstrdup(buffer);
6985                         }
6986                         break;
6987
6988                 case PGC_STRING:
6989                         {
6990                                 struct config_string *lconf = (struct config_string *) conf;
6991
6992                                 /* min_val */
6993                                 values[9] = NULL;
6994
6995                                 /* max_val */
6996                                 values[10] = NULL;
6997
6998                                 /* enumvals */
6999                                 values[11] = NULL;
7000
7001                                 /* boot_val */
7002                                 if (lconf->boot_val == NULL)
7003                                         values[12] = NULL;
7004                                 else
7005                                         values[12] = pstrdup(lconf->boot_val);
7006
7007                                 /* reset_val */
7008                                 if (lconf->reset_val == NULL)
7009                                         values[13] = NULL;
7010                                 else
7011                                         values[13] = pstrdup(lconf->reset_val);
7012                         }
7013                         break;
7014
7015                 case PGC_ENUM:
7016                         {
7017                                 struct config_enum *lconf = (struct config_enum *) conf;
7018
7019                                 /* min_val */
7020                                 values[9] = NULL;
7021
7022                                 /* max_val */
7023                                 values[10] = NULL;
7024
7025                                 /* enumvals */
7026
7027                                 /*
7028                                  * NOTE! enumvals with double quotes in them are not
7029                                  * supported!
7030                                  */
7031                                 values[11] = config_enum_get_options((struct config_enum *) conf,
7032                                                                                                          "{\"", "\"}", "\",\"");
7033
7034                                 /* boot_val */
7035                                 values[12] = pstrdup(config_enum_lookup_by_value(lconf,
7036                                                                                                                    lconf->boot_val));
7037
7038                                 /* reset_val */
7039                                 values[13] = pstrdup(config_enum_lookup_by_value(lconf,
7040                                                                                                                   lconf->reset_val));
7041                         }
7042                         break;
7043
7044                 default:
7045                         {
7046                                 /*
7047                                  * should never get here, but in case we do, set 'em to NULL
7048                                  */
7049
7050                                 /* min_val */
7051                                 values[9] = NULL;
7052
7053                                 /* max_val */
7054                                 values[10] = NULL;
7055
7056                                 /* enumvals */
7057                                 values[11] = NULL;
7058
7059                                 /* boot_val */
7060                                 values[12] = NULL;
7061
7062                                 /* reset_val */
7063                                 values[13] = NULL;
7064                         }
7065                         break;
7066         }
7067
7068         /*
7069          * If the setting came from a config file, set the source location. For
7070          * security reasons, we don't show source file/line number for
7071          * non-superusers.
7072          */
7073         if (conf->source == PGC_S_FILE && superuser())
7074         {
7075                 values[14] = conf->sourcefile;
7076                 snprintf(buffer, sizeof(buffer), "%d", conf->sourceline);
7077                 values[15] = pstrdup(buffer);
7078         }
7079         else
7080         {
7081                 values[14] = NULL;
7082                 values[15] = NULL;
7083         }
7084 }
7085
7086 /*
7087  * Return the total number of GUC variables
7088  */
7089 int
7090 GetNumConfigOptions(void)
7091 {
7092         return num_guc_variables;
7093 }
7094
7095 /*
7096  * show_config_by_name - equiv to SHOW X command but implemented as
7097  * a function.
7098  */
7099 Datum
7100 show_config_by_name(PG_FUNCTION_ARGS)
7101 {
7102         char       *varname;
7103         char       *varval;
7104
7105         /* Get the GUC variable name */
7106         varname = TextDatumGetCString(PG_GETARG_DATUM(0));
7107
7108         /* Get the value */
7109         varval = GetConfigOptionByName(varname, NULL);
7110
7111         /* Convert to text */
7112         PG_RETURN_TEXT_P(cstring_to_text(varval));
7113 }
7114
7115 /*
7116  * show_all_settings - equiv to SHOW ALL command but implemented as
7117  * a Table Function.
7118  */
7119 #define NUM_PG_SETTINGS_ATTS    16
7120
7121 Datum
7122 show_all_settings(PG_FUNCTION_ARGS)
7123 {
7124         FuncCallContext *funcctx;
7125         TupleDesc       tupdesc;
7126         int                     call_cntr;
7127         int                     max_calls;
7128         AttInMetadata *attinmeta;
7129         MemoryContext oldcontext;
7130
7131         /* stuff done only on the first call of the function */
7132         if (SRF_IS_FIRSTCALL())
7133         {
7134                 /* create a function context for cross-call persistence */
7135                 funcctx = SRF_FIRSTCALL_INIT();
7136
7137                 /*
7138                  * switch to memory context appropriate for multiple function calls
7139                  */
7140                 oldcontext = MemoryContextSwitchTo(funcctx->multi_call_memory_ctx);
7141
7142                 /*
7143                  * need a tuple descriptor representing NUM_PG_SETTINGS_ATTS columns
7144                  * of the appropriate types
7145                  */
7146                 tupdesc = CreateTemplateTupleDesc(NUM_PG_SETTINGS_ATTS, false);
7147                 TupleDescInitEntry(tupdesc, (AttrNumber) 1, "name",
7148                                                    TEXTOID, -1, 0);
7149                 TupleDescInitEntry(tupdesc, (AttrNumber) 2, "setting",
7150                                                    TEXTOID, -1, 0);
7151                 TupleDescInitEntry(tupdesc, (AttrNumber) 3, "unit",
7152                                                    TEXTOID, -1, 0);
7153                 TupleDescInitEntry(tupdesc, (AttrNumber) 4, "category",
7154                                                    TEXTOID, -1, 0);
7155                 TupleDescInitEntry(tupdesc, (AttrNumber) 5, "short_desc",
7156                                                    TEXTOID, -1, 0);
7157                 TupleDescInitEntry(tupdesc, (AttrNumber) 6, "extra_desc",
7158                                                    TEXTOID, -1, 0);
7159                 TupleDescInitEntry(tupdesc, (AttrNumber) 7, "context",
7160                                                    TEXTOID, -1, 0);
7161                 TupleDescInitEntry(tupdesc, (AttrNumber) 8, "vartype",
7162                                                    TEXTOID, -1, 0);
7163                 TupleDescInitEntry(tupdesc, (AttrNumber) 9, "source",
7164                                                    TEXTOID, -1, 0);
7165                 TupleDescInitEntry(tupdesc, (AttrNumber) 10, "min_val",
7166                                                    TEXTOID, -1, 0);
7167                 TupleDescInitEntry(tupdesc, (AttrNumber) 11, "max_val",
7168                                                    TEXTOID, -1, 0);
7169                 TupleDescInitEntry(tupdesc, (AttrNumber) 12, "enumvals",
7170                                                    TEXTARRAYOID, -1, 0);
7171                 TupleDescInitEntry(tupdesc, (AttrNumber) 13, "boot_val",
7172                                                    TEXTOID, -1, 0);
7173                 TupleDescInitEntry(tupdesc, (AttrNumber) 14, "reset_val",
7174                                                    TEXTOID, -1, 0);
7175                 TupleDescInitEntry(tupdesc, (AttrNumber) 15, "sourcefile",
7176                                                    TEXTOID, -1, 0);
7177                 TupleDescInitEntry(tupdesc, (AttrNumber) 16, "sourceline",
7178                                                    INT4OID, -1, 0);
7179
7180                 /*
7181                  * Generate attribute metadata needed later to produce tuples from raw
7182                  * C strings
7183                  */
7184                 attinmeta = TupleDescGetAttInMetadata(tupdesc);
7185                 funcctx->attinmeta = attinmeta;
7186
7187                 /* total number of tuples to be returned */
7188                 funcctx->max_calls = GetNumConfigOptions();
7189
7190                 MemoryContextSwitchTo(oldcontext);
7191         }
7192
7193         /* stuff done on every call of the function */
7194         funcctx = SRF_PERCALL_SETUP();
7195
7196         call_cntr = funcctx->call_cntr;
7197         max_calls = funcctx->max_calls;
7198         attinmeta = funcctx->attinmeta;
7199
7200         if (call_cntr < max_calls)      /* do when there is more left to send */
7201         {
7202                 char       *values[NUM_PG_SETTINGS_ATTS];
7203                 bool            noshow;
7204                 HeapTuple       tuple;
7205                 Datum           result;
7206
7207                 /*
7208                  * Get the next visible GUC variable name and value
7209                  */
7210                 do
7211                 {
7212                         GetConfigOptionByNum(call_cntr, (const char **) values, &noshow);
7213                         if (noshow)
7214                         {
7215                                 /* bump the counter and get the next config setting */
7216                                 call_cntr = ++funcctx->call_cntr;
7217
7218                                 /* make sure we haven't gone too far now */
7219                                 if (call_cntr >= max_calls)
7220                                         SRF_RETURN_DONE(funcctx);
7221                         }
7222                 } while (noshow);
7223
7224                 /* build a tuple */
7225                 tuple = BuildTupleFromCStrings(attinmeta, values);
7226
7227                 /* make the tuple into a datum */
7228                 result = HeapTupleGetDatum(tuple);
7229
7230                 SRF_RETURN_NEXT(funcctx, result);
7231         }
7232         else
7233         {
7234                 /* do when there is no more left */
7235                 SRF_RETURN_DONE(funcctx);
7236         }
7237 }
7238
7239 static char *
7240 _ShowOption(struct config_generic * record, bool use_units)
7241 {
7242         char            buffer[256];
7243         const char *val;
7244
7245         switch (record->vartype)
7246         {
7247                 case PGC_BOOL:
7248                         {
7249                                 struct config_bool *conf = (struct config_bool *) record;
7250
7251                                 if (conf->show_hook)
7252                                         val = (*conf->show_hook) ();
7253                                 else
7254                                         val = *conf->variable ? "on" : "off";
7255                         }
7256                         break;
7257
7258                 case PGC_INT:
7259                         {
7260                                 struct config_int *conf = (struct config_int *) record;
7261
7262                                 if (conf->show_hook)
7263                                         val = (*conf->show_hook) ();
7264                                 else
7265                                 {
7266                                         /*
7267                                          * Use int64 arithmetic to avoid overflows in units
7268                                          * conversion.
7269                                          */
7270                                         int64           result = *conf->variable;
7271                                         const char *unit;
7272
7273                                         if (use_units && result > 0 &&
7274                                                 (record->flags & GUC_UNIT_MEMORY))
7275                                         {
7276                                                 switch (record->flags & GUC_UNIT_MEMORY)
7277                                                 {
7278                                                         case GUC_UNIT_BLOCKS:
7279                                                                 result *= BLCKSZ / 1024;
7280                                                                 break;
7281                                                         case GUC_UNIT_XBLOCKS:
7282                                                                 result *= XLOG_BLCKSZ / 1024;
7283                                                                 break;
7284                                                 }
7285
7286                                                 if (result % KB_PER_GB == 0)
7287                                                 {
7288                                                         result /= KB_PER_GB;
7289                                                         unit = "GB";
7290                                                 }
7291                                                 else if (result % KB_PER_MB == 0)
7292                                                 {
7293                                                         result /= KB_PER_MB;
7294                                                         unit = "MB";
7295                                                 }
7296                                                 else
7297                                                 {
7298                                                         unit = "kB";
7299                                                 }
7300                                         }
7301                                         else if (use_units && result > 0 &&
7302                                                          (record->flags & GUC_UNIT_TIME))
7303                                         {
7304                                                 switch (record->flags & GUC_UNIT_TIME)
7305                                                 {
7306                                                         case GUC_UNIT_S:
7307                                                                 result *= MS_PER_S;
7308                                                                 break;
7309                                                         case GUC_UNIT_MIN:
7310                                                                 result *= MS_PER_MIN;
7311                                                                 break;
7312                                                 }
7313
7314                                                 if (result % MS_PER_D == 0)
7315                                                 {
7316                                                         result /= MS_PER_D;
7317                                                         unit = "d";
7318                                                 }
7319                                                 else if (result % MS_PER_H == 0)
7320                                                 {
7321                                                         result /= MS_PER_H;
7322                                                         unit = "h";
7323                                                 }
7324                                                 else if (result % MS_PER_MIN == 0)
7325                                                 {
7326                                                         result /= MS_PER_MIN;
7327                                                         unit = "min";
7328                                                 }
7329                                                 else if (result % MS_PER_S == 0)
7330                                                 {
7331                                                         result /= MS_PER_S;
7332                                                         unit = "s";
7333                                                 }
7334                                                 else
7335                                                 {
7336                                                         unit = "ms";
7337                                                 }
7338                                         }
7339                                         else
7340                                                 unit = "";
7341
7342                                         snprintf(buffer, sizeof(buffer), INT64_FORMAT "%s",
7343                                                          result, unit);
7344                                         val = buffer;
7345                                 }
7346                         }
7347                         break;
7348
7349                 case PGC_REAL:
7350                         {
7351                                 struct config_real *conf = (struct config_real *) record;
7352
7353                                 if (conf->show_hook)
7354                                         val = (*conf->show_hook) ();
7355                                 else
7356                                 {
7357                                         snprintf(buffer, sizeof(buffer), "%g",
7358                                                          *conf->variable);
7359                                         val = buffer;
7360                                 }
7361                         }
7362                         break;
7363
7364                 case PGC_STRING:
7365                         {
7366                                 struct config_string *conf = (struct config_string *) record;
7367
7368                                 if (conf->show_hook)
7369                                         val = (*conf->show_hook) ();
7370                                 else if (*conf->variable && **conf->variable)
7371                                         val = *conf->variable;
7372                                 else
7373                                         val = "";
7374                         }
7375                         break;
7376
7377                 case PGC_ENUM:
7378                         {
7379                                 struct config_enum *conf = (struct config_enum *) record;
7380
7381                                 if (conf->show_hook)
7382                                         val = (*conf->show_hook) ();
7383                                 else
7384                                         val = config_enum_lookup_by_value(conf, *conf->variable);
7385                         }
7386                         break;
7387
7388                 default:
7389                         /* just to keep compiler quiet */
7390                         val = "???";
7391                         break;
7392         }
7393
7394         return pstrdup(val);
7395 }
7396
7397
7398 #ifdef EXEC_BACKEND
7399
7400 /*
7401  *      These routines dump out all non-default GUC options into a binary
7402  *      file that is read by all exec'ed backends.  The format is:
7403  *
7404  *              variable name, string, null terminated
7405  *              variable value, string, null terminated
7406  *              variable sourcefile, string, null terminated (empty if none)
7407  *              variable sourceline, integer
7408  *              variable source, integer
7409  *              variable scontext, integer
7410  */
7411 static void
7412 write_one_nondefault_variable(FILE *fp, struct config_generic * gconf)
7413 {
7414         if (gconf->source == PGC_S_DEFAULT)
7415                 return;
7416
7417         fprintf(fp, "%s", gconf->name);
7418         fputc(0, fp);
7419
7420         switch (gconf->vartype)
7421         {
7422                 case PGC_BOOL:
7423                         {
7424                                 struct config_bool *conf = (struct config_bool *) gconf;
7425
7426                                 if (*conf->variable)
7427                                         fprintf(fp, "true");
7428                                 else
7429                                         fprintf(fp, "false");
7430                         }
7431                         break;
7432
7433                 case PGC_INT:
7434                         {
7435                                 struct config_int *conf = (struct config_int *) gconf;
7436
7437                                 fprintf(fp, "%d", *conf->variable);
7438                         }
7439                         break;
7440
7441                 case PGC_REAL:
7442                         {
7443                                 struct config_real *conf = (struct config_real *) gconf;
7444
7445                                 fprintf(fp, "%.17g", *conf->variable);
7446                         }
7447                         break;
7448
7449                 case PGC_STRING:
7450                         {
7451                                 struct config_string *conf = (struct config_string *) gconf;
7452
7453                                 fprintf(fp, "%s", *conf->variable);
7454                         }
7455                         break;
7456
7457                 case PGC_ENUM:
7458                         {
7459                                 struct config_enum *conf = (struct config_enum *) gconf;
7460
7461                                 fprintf(fp, "%s",
7462                                                 config_enum_lookup_by_value(conf, *conf->variable));
7463                         }
7464                         break;
7465         }
7466
7467         fputc(0, fp);
7468
7469         if (gconf->sourcefile)
7470                 fprintf(fp, "%s", gconf->sourcefile);
7471         fputc(0, fp);
7472
7473         fwrite(&gconf->sourceline, 1, sizeof(gconf->sourceline), fp);
7474         fwrite(&gconf->source, 1, sizeof(gconf->source), fp);
7475         fwrite(&gconf->scontext, 1, sizeof(gconf->scontext), fp);
7476 }
7477
7478 void
7479 write_nondefault_variables(GucContext context)
7480 {
7481         int                     elevel;
7482         FILE       *fp;
7483         int                     i;
7484
7485         Assert(context == PGC_POSTMASTER || context == PGC_SIGHUP);
7486
7487         elevel = (context == PGC_SIGHUP) ? LOG : ERROR;
7488
7489         /*
7490          * Open file
7491          */
7492         fp = AllocateFile(CONFIG_EXEC_PARAMS_NEW, "w");
7493         if (!fp)
7494         {
7495                 ereport(elevel,
7496                                 (errcode_for_file_access(),
7497                                  errmsg("could not write to file \"%s\": %m",
7498                                                 CONFIG_EXEC_PARAMS_NEW)));
7499                 return;
7500         }
7501
7502         for (i = 0; i < num_guc_variables; i++)
7503         {
7504                 write_one_nondefault_variable(fp, guc_variables[i]);
7505         }
7506
7507         if (FreeFile(fp))
7508         {
7509                 ereport(elevel,
7510                                 (errcode_for_file_access(),
7511                                  errmsg("could not write to file \"%s\": %m",
7512                                                 CONFIG_EXEC_PARAMS_NEW)));
7513                 return;
7514         }
7515
7516         /*
7517          * Put new file in place.  This could delay on Win32, but we don't hold
7518          * any exclusive locks.
7519          */
7520         rename(CONFIG_EXEC_PARAMS_NEW, CONFIG_EXEC_PARAMS);
7521 }
7522
7523
7524 /*
7525  *      Read string, including null byte from file
7526  *
7527  *      Return NULL on EOF and nothing read
7528  */
7529 static char *
7530 read_string_with_null(FILE *fp)
7531 {
7532         int                     i = 0,
7533                                 ch,
7534                                 maxlen = 256;
7535         char       *str = NULL;
7536
7537         do
7538         {
7539                 if ((ch = fgetc(fp)) == EOF)
7540                 {
7541                         if (i == 0)
7542                                 return NULL;
7543                         else
7544                                 elog(FATAL, "invalid format of exec config params file");
7545                 }
7546                 if (i == 0)
7547                         str = guc_malloc(FATAL, maxlen);
7548                 else if (i == maxlen)
7549                         str = guc_realloc(FATAL, str, maxlen *= 2);
7550                 str[i++] = ch;
7551         } while (ch != 0);
7552
7553         return str;
7554 }
7555
7556
7557 /*
7558  *      This routine loads a previous postmaster dump of its non-default
7559  *      settings.
7560  */
7561 void
7562 read_nondefault_variables(void)
7563 {
7564         FILE       *fp;
7565         char       *varname,
7566                            *varvalue,
7567                            *varsourcefile;
7568         int                     varsourceline;
7569         GucSource       varsource;
7570         GucContext      varscontext;
7571
7572         /*
7573          * Open file
7574          */
7575         fp = AllocateFile(CONFIG_EXEC_PARAMS, "r");
7576         if (!fp)
7577         {
7578                 /* File not found is fine */
7579                 if (errno != ENOENT)
7580                         ereport(FATAL,
7581                                         (errcode_for_file_access(),
7582                                          errmsg("could not read from file \"%s\": %m",
7583                                                         CONFIG_EXEC_PARAMS)));
7584                 return;
7585         }
7586
7587         for (;;)
7588         {
7589                 struct config_generic *record;
7590
7591                 if ((varname = read_string_with_null(fp)) == NULL)
7592                         break;
7593
7594                 if ((record = find_option(varname, true, FATAL)) == NULL)
7595                         elog(FATAL, "failed to locate variable \"%s\" in exec config params file", varname);
7596
7597                 if ((varvalue = read_string_with_null(fp)) == NULL)
7598                         elog(FATAL, "invalid format of exec config params file");
7599                 if ((varsourcefile = read_string_with_null(fp)) == NULL)
7600                         elog(FATAL, "invalid format of exec config params file");
7601                 if (fread(&varsourceline, 1, sizeof(varsourceline), fp) != sizeof(varsourceline))
7602                         elog(FATAL, "invalid format of exec config params file");
7603                 if (fread(&varsource, 1, sizeof(varsource), fp) != sizeof(varsource))
7604                         elog(FATAL, "invalid format of exec config params file");
7605                 if (fread(&varscontext, 1, sizeof(varscontext), fp) != sizeof(varscontext))
7606                         elog(FATAL, "invalid format of exec config params file");
7607
7608                 (void) set_config_option(varname, varvalue,
7609                                                                  varscontext, varsource,
7610                                                                  GUC_ACTION_SET, true, 0);
7611                 if (varsourcefile[0])
7612                         set_config_sourcefile(varname, varsourcefile, varsourceline);
7613
7614                 free(varname);
7615                 free(varvalue);
7616                 free(varsourcefile);
7617         }
7618
7619         FreeFile(fp);
7620 }
7621 #endif   /* EXEC_BACKEND */
7622
7623
7624 /*
7625  * A little "long argument" simulation, although not quite GNU
7626  * compliant. Takes a string of the form "some-option=some value" and
7627  * returns name = "some_option" and value = "some value" in malloc'ed
7628  * storage. Note that '-' is converted to '_' in the option name. If
7629  * there is no '=' in the input string then value will be NULL.
7630  */
7631 void
7632 ParseLongOption(const char *string, char **name, char **value)
7633 {
7634         size_t          equal_pos;
7635         char       *cp;
7636
7637         AssertArg(string);
7638         AssertArg(name);
7639         AssertArg(value);
7640
7641         equal_pos = strcspn(string, "=");
7642
7643         if (string[equal_pos] == '=')
7644         {
7645                 *name = guc_malloc(FATAL, equal_pos + 1);
7646                 strlcpy(*name, string, equal_pos + 1);
7647
7648                 *value = guc_strdup(FATAL, &string[equal_pos + 1]);
7649         }
7650         else
7651         {
7652                 /* no equal sign in string */
7653                 *name = guc_strdup(FATAL, string);
7654                 *value = NULL;
7655         }
7656
7657         for (cp = *name; *cp; cp++)
7658                 if (*cp == '-')
7659                         *cp = '_';
7660 }
7661
7662
7663 /*
7664  * Handle options fetched from pg_db_role_setting.setconfig,
7665  * pg_proc.proconfig, etc.      Caller must specify proper context/source/action.
7666  *
7667  * The array parameter must be an array of TEXT (it must not be NULL).
7668  */
7669 void
7670 ProcessGUCArray(ArrayType *array,
7671                                 GucContext context, GucSource source, GucAction action)
7672 {
7673         int                     i;
7674
7675         Assert(array != NULL);
7676         Assert(ARR_ELEMTYPE(array) == TEXTOID);
7677         Assert(ARR_NDIM(array) == 1);
7678         Assert(ARR_LBOUND(array)[0] == 1);
7679
7680         for (i = 1; i <= ARR_DIMS(array)[0]; i++)
7681         {
7682                 Datum           d;
7683                 bool            isnull;
7684                 char       *s;
7685                 char       *name;
7686                 char       *value;
7687
7688                 d = array_ref(array, 1, &i,
7689                                           -1 /* varlenarray */ ,
7690                                           -1 /* TEXT's typlen */ ,
7691                                           false /* TEXT's typbyval */ ,
7692                                           'i' /* TEXT's typalign */ ,
7693                                           &isnull);
7694
7695                 if (isnull)
7696                         continue;
7697
7698                 s = TextDatumGetCString(d);
7699
7700                 ParseLongOption(s, &name, &value);
7701                 if (!value)
7702                 {
7703                         ereport(WARNING,
7704                                         (errcode(ERRCODE_SYNTAX_ERROR),
7705                                          errmsg("could not parse setting for parameter \"%s\"",
7706                                                         name)));
7707                         free(name);
7708                         continue;
7709                 }
7710
7711                 (void) set_config_option(name, value,
7712                                                                  context, source,
7713                                                                  action, true, 0);
7714
7715                 free(name);
7716                 if (value)
7717                         free(value);
7718                 pfree(s);
7719         }
7720 }
7721
7722
7723 /*
7724  * Add an entry to an option array.  The array parameter may be NULL
7725  * to indicate the current table entry is NULL.
7726  */
7727 ArrayType *
7728 GUCArrayAdd(ArrayType *array, const char *name, const char *value)
7729 {
7730         struct config_generic *record;
7731         Datum           datum;
7732         char       *newval;
7733         ArrayType  *a;
7734
7735         Assert(name);
7736         Assert(value);
7737
7738         /* test if the option is valid and we're allowed to set it */
7739         (void) validate_option_array_item(name, value, false);
7740
7741         /* normalize name (converts obsolete GUC names to modern spellings) */
7742         record = find_option(name, false, WARNING);
7743         if (record)
7744                 name = record->name;
7745
7746         /* build new item for array */
7747         newval = palloc(strlen(name) + 1 + strlen(value) + 1);
7748         sprintf(newval, "%s=%s", name, value);
7749         datum = CStringGetTextDatum(newval);
7750
7751         if (array)
7752         {
7753                 int                     index;
7754                 bool            isnull;
7755                 int                     i;
7756
7757                 Assert(ARR_ELEMTYPE(array) == TEXTOID);
7758                 Assert(ARR_NDIM(array) == 1);
7759                 Assert(ARR_LBOUND(array)[0] == 1);
7760
7761                 index = ARR_DIMS(array)[0] + 1; /* add after end */
7762
7763                 for (i = 1; i <= ARR_DIMS(array)[0]; i++)
7764                 {
7765                         Datum           d;
7766                         char       *current;
7767
7768                         d = array_ref(array, 1, &i,
7769                                                   -1 /* varlenarray */ ,
7770                                                   -1 /* TEXT's typlen */ ,
7771                                                   false /* TEXT's typbyval */ ,
7772                                                   'i' /* TEXT's typalign */ ,
7773                                                   &isnull);
7774                         if (isnull)
7775                                 continue;
7776                         current = TextDatumGetCString(d);
7777
7778                         /* check for match up through and including '=' */
7779                         if (strncmp(current, newval, strlen(name) + 1) == 0)
7780                         {
7781                                 index = i;
7782                                 break;
7783                         }
7784                 }
7785
7786                 a = array_set(array, 1, &index,
7787                                           datum,
7788                                           false,
7789                                           -1 /* varlena array */ ,
7790                                           -1 /* TEXT's typlen */ ,
7791                                           false /* TEXT's typbyval */ ,
7792                                           'i' /* TEXT's typalign */ );
7793         }
7794         else
7795                 a = construct_array(&datum, 1,
7796                                                         TEXTOID,
7797                                                         -1, false, 'i');
7798
7799         return a;
7800 }
7801
7802
7803 /*
7804  * Delete an entry from an option array.  The array parameter may be NULL
7805  * to indicate the current table entry is NULL.  Also, if the return value
7806  * is NULL then a null should be stored.
7807  */
7808 ArrayType *
7809 GUCArrayDelete(ArrayType *array, const char *name)
7810 {
7811         struct config_generic *record;
7812         ArrayType  *newarray;
7813         int                     i;
7814         int                     index;
7815
7816         Assert(name);
7817
7818         /* test if the option is valid and we're allowed to set it */
7819         (void) validate_option_array_item(name, NULL, false);
7820
7821         /* normalize name (converts obsolete GUC names to modern spellings) */
7822         record = find_option(name, false, WARNING);
7823         if (record)
7824                 name = record->name;
7825
7826         /* if array is currently null, then surely nothing to delete */
7827         if (!array)
7828                 return NULL;
7829
7830         newarray = NULL;
7831         index = 1;
7832
7833         for (i = 1; i <= ARR_DIMS(array)[0]; i++)
7834         {
7835                 Datum           d;
7836                 char       *val;
7837                 bool            isnull;
7838
7839                 d = array_ref(array, 1, &i,
7840                                           -1 /* varlenarray */ ,
7841                                           -1 /* TEXT's typlen */ ,
7842                                           false /* TEXT's typbyval */ ,
7843                                           'i' /* TEXT's typalign */ ,
7844                                           &isnull);
7845                 if (isnull)
7846                         continue;
7847                 val = TextDatumGetCString(d);
7848
7849                 /* ignore entry if it's what we want to delete */
7850                 if (strncmp(val, name, strlen(name)) == 0
7851                         && val[strlen(name)] == '=')
7852                         continue;
7853
7854                 /* else add it to the output array */
7855                 if (newarray)
7856                         newarray = array_set(newarray, 1, &index,
7857                                                                  d,
7858                                                                  false,
7859                                                                  -1 /* varlenarray */ ,
7860                                                                  -1 /* TEXT's typlen */ ,
7861                                                                  false /* TEXT's typbyval */ ,
7862                                                                  'i' /* TEXT's typalign */ );
7863                 else
7864                         newarray = construct_array(&d, 1,
7865                                                                            TEXTOID,
7866                                                                            -1, false, 'i');
7867
7868                 index++;
7869         }
7870
7871         return newarray;
7872 }
7873
7874
7875 /*
7876  * Given a GUC array, delete all settings from it that our permission
7877  * level allows: if superuser, delete them all; if regular user, only
7878  * those that are PGC_USERSET
7879  */
7880 ArrayType *
7881 GUCArrayReset(ArrayType *array)
7882 {
7883         ArrayType  *newarray;
7884         int                     i;
7885         int                     index;
7886
7887         /* if array is currently null, nothing to do */
7888         if (!array)
7889                 return NULL;
7890
7891         /* if we're superuser, we can delete everything, so just do it */
7892         if (superuser())
7893                 return NULL;
7894
7895         newarray = NULL;
7896         index = 1;
7897
7898         for (i = 1; i <= ARR_DIMS(array)[0]; i++)
7899         {
7900                 Datum           d;
7901                 char       *val;
7902                 char       *eqsgn;
7903                 bool            isnull;
7904
7905                 d = array_ref(array, 1, &i,
7906                                           -1 /* varlenarray */ ,
7907                                           -1 /* TEXT's typlen */ ,
7908                                           false /* TEXT's typbyval */ ,
7909                                           'i' /* TEXT's typalign */ ,
7910                                           &isnull);
7911                 if (isnull)
7912                         continue;
7913                 val = TextDatumGetCString(d);
7914
7915                 eqsgn = strchr(val, '=');
7916                 *eqsgn = '\0';
7917
7918                 /* skip if we have permission to delete it */
7919                 if (validate_option_array_item(val, NULL, true))
7920                         continue;
7921
7922                 /* else add it to the output array */
7923                 if (newarray)
7924                         newarray = array_set(newarray, 1, &index,
7925                                                                  d,
7926                                                                  false,
7927                                                                  -1 /* varlenarray */ ,
7928                                                                  -1 /* TEXT's typlen */ ,
7929                                                                  false /* TEXT's typbyval */ ,
7930                                                                  'i' /* TEXT's typalign */ );
7931                 else
7932                         newarray = construct_array(&d, 1,
7933                                                                            TEXTOID,
7934                                                                            -1, false, 'i');
7935
7936                 index++;
7937                 pfree(val);
7938         }
7939
7940         return newarray;
7941 }
7942
7943 /*
7944  * Validate a proposed option setting for GUCArrayAdd/Delete/Reset.
7945  *
7946  * name is the option name.  value is the proposed value for the Add case,
7947  * or NULL for the Delete/Reset cases.  If skipIfNoPermissions is true, it's
7948  * not an error to have no permissions to set the option.
7949  *
7950  * Returns TRUE if OK, FALSE if skipIfNoPermissions is true and user does not
7951  * have permission to change this option (all other error cases result in an
7952  * error being thrown).
7953  */
7954 static bool
7955 validate_option_array_item(const char *name, const char *value,
7956                                                    bool skipIfNoPermissions)
7957
7958 {
7959         struct config_generic *gconf;
7960
7961         /*
7962          * There are three cases to consider:
7963          *
7964          * name is a known GUC variable.  Check the value normally, check
7965          * permissions normally (ie, allow if variable is USERSET, or if it's
7966          * SUSET and user is superuser).
7967          *
7968          * name is not known, but exists or can be created as a placeholder (i.e.,
7969          * it has a prefixed name).  We allow this case if you're a superuser,
7970          * otherwise not.  Superusers are assumed to know what they're doing.
7971          * We can't allow it for other users, because when the placeholder is
7972          * resolved it might turn out to be a SUSET variable;
7973          * define_custom_variable assumes we checked that.
7974          *
7975          * name is not known and can't be created as a placeholder.  Throw error,
7976          * unless skipIfNoPermissions is true, in which case return FALSE.
7977          */
7978         gconf = find_option(name, true, WARNING);
7979         if (!gconf)
7980         {
7981                 /* not known, failed to make a placeholder */
7982                 if (skipIfNoPermissions)
7983                         return false;
7984                 ereport(ERROR,
7985                                 (errcode(ERRCODE_UNDEFINED_OBJECT),
7986                                  errmsg("unrecognized configuration parameter \"%s\"",
7987                                                 name)));
7988         }
7989
7990         if (gconf->flags & GUC_CUSTOM_PLACEHOLDER)
7991         {
7992                 /*
7993                  * We cannot do any meaningful check on the value, so only permissions
7994                  * are useful to check.
7995                  */
7996                 if (superuser())
7997                         return true;
7998                 if (skipIfNoPermissions)
7999                         return false;
8000                 ereport(ERROR,
8001                                 (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
8002                                  errmsg("permission denied to set parameter \"%s\"", name)));
8003         }
8004
8005         /* manual permissions check so we can avoid an error being thrown */
8006         if (gconf->context == PGC_USERSET)
8007                  /* ok */ ;
8008         else if (gconf->context == PGC_SUSET && superuser())
8009                  /* ok */ ;
8010         else if (skipIfNoPermissions)
8011                 return false;
8012         /* if a permissions error should be thrown, let set_config_option do it */
8013
8014         /* test for permissions and valid option value */
8015         (void) set_config_option(name, value,
8016                                                          superuser() ? PGC_SUSET : PGC_USERSET,
8017                                                          PGC_S_TEST, GUC_ACTION_SET, false, 0);
8018
8019         return true;
8020 }
8021
8022
8023 /*
8024  * Called by check_hooks that want to override the normal
8025  * ERRCODE_INVALID_PARAMETER_VALUE SQLSTATE for check hook failures.
8026  *
8027  * Note that GUC_check_errmsg() etc are just macros that result in a direct
8028  * assignment to the associated variables.      That is ugly, but forced by the
8029  * limitations of C's macro mechanisms.
8030  */
8031 void
8032 GUC_check_errcode(int sqlerrcode)
8033 {
8034         GUC_check_errcode_value = sqlerrcode;
8035 }
8036
8037
8038 /*
8039  * Convenience functions to manage calling a variable's check_hook.
8040  * These mostly take care of the protocol for letting check hooks supply
8041  * portions of the error report on failure.
8042  */
8043
8044 static bool
8045 call_bool_check_hook(struct config_bool * conf, bool *newval, void **extra,
8046                                          GucSource source, int elevel)
8047 {
8048         /* Quick success if no hook */
8049         if (!conf->check_hook)
8050                 return true;
8051
8052         /* Reset variables that might be set by hook */
8053         GUC_check_errcode_value = ERRCODE_INVALID_PARAMETER_VALUE;
8054         GUC_check_errmsg_string = NULL;
8055         GUC_check_errdetail_string = NULL;
8056         GUC_check_errhint_string = NULL;
8057
8058         if (!(*conf->check_hook) (newval, extra, source))
8059         {
8060                 ereport(elevel,
8061                                 (errcode(GUC_check_errcode_value),
8062                                  GUC_check_errmsg_string ?
8063                                  errmsg_internal("%s", GUC_check_errmsg_string) :
8064                                  errmsg("invalid value for parameter \"%s\": %d",
8065                                                 conf->gen.name, (int) *newval),
8066                                  GUC_check_errdetail_string ?
8067                                  errdetail_internal("%s", GUC_check_errdetail_string) : 0,
8068                                  GUC_check_errhint_string ?
8069                                  errhint("%s", GUC_check_errhint_string) : 0));
8070                 /* Flush any strings created in ErrorContext */
8071                 FlushErrorState();
8072                 return false;
8073         }
8074
8075         return true;
8076 }
8077
8078 static bool
8079 call_int_check_hook(struct config_int * conf, int *newval, void **extra,
8080                                         GucSource source, int elevel)
8081 {
8082         /* Quick success if no hook */
8083         if (!conf->check_hook)
8084                 return true;
8085
8086         /* Reset variables that might be set by hook */
8087         GUC_check_errcode_value = ERRCODE_INVALID_PARAMETER_VALUE;
8088         GUC_check_errmsg_string = NULL;
8089         GUC_check_errdetail_string = NULL;
8090         GUC_check_errhint_string = NULL;
8091
8092         if (!(*conf->check_hook) (newval, extra, source))
8093         {
8094                 ereport(elevel,
8095                                 (errcode(GUC_check_errcode_value),
8096                                  GUC_check_errmsg_string ?
8097                                  errmsg_internal("%s", GUC_check_errmsg_string) :
8098                                  errmsg("invalid value for parameter \"%s\": %d",
8099                                                 conf->gen.name, *newval),
8100                                  GUC_check_errdetail_string ?
8101                                  errdetail_internal("%s", GUC_check_errdetail_string) : 0,
8102                                  GUC_check_errhint_string ?
8103                                  errhint("%s", GUC_check_errhint_string) : 0));
8104                 /* Flush any strings created in ErrorContext */
8105                 FlushErrorState();
8106                 return false;
8107         }
8108
8109         return true;
8110 }
8111
8112 static bool
8113 call_real_check_hook(struct config_real * conf, double *newval, void **extra,
8114                                          GucSource source, int elevel)
8115 {
8116         /* Quick success if no hook */
8117         if (!conf->check_hook)
8118                 return true;
8119
8120         /* Reset variables that might be set by hook */
8121         GUC_check_errcode_value = ERRCODE_INVALID_PARAMETER_VALUE;
8122         GUC_check_errmsg_string = NULL;
8123         GUC_check_errdetail_string = NULL;
8124         GUC_check_errhint_string = NULL;
8125
8126         if (!(*conf->check_hook) (newval, extra, source))
8127         {
8128                 ereport(elevel,
8129                                 (errcode(GUC_check_errcode_value),
8130                                  GUC_check_errmsg_string ?
8131                                  errmsg_internal("%s", GUC_check_errmsg_string) :
8132                                  errmsg("invalid value for parameter \"%s\": %g",
8133                                                 conf->gen.name, *newval),
8134                                  GUC_check_errdetail_string ?
8135                                  errdetail_internal("%s", GUC_check_errdetail_string) : 0,
8136                                  GUC_check_errhint_string ?
8137                                  errhint("%s", GUC_check_errhint_string) : 0));
8138                 /* Flush any strings created in ErrorContext */
8139                 FlushErrorState();
8140                 return false;
8141         }
8142
8143         return true;
8144 }
8145
8146 static bool
8147 call_string_check_hook(struct config_string * conf, char **newval, void **extra,
8148                                            GucSource source, int elevel)
8149 {
8150         /* Quick success if no hook */
8151         if (!conf->check_hook)
8152                 return true;
8153
8154         /* Reset variables that might be set by hook */
8155         GUC_check_errcode_value = ERRCODE_INVALID_PARAMETER_VALUE;
8156         GUC_check_errmsg_string = NULL;
8157         GUC_check_errdetail_string = NULL;
8158         GUC_check_errhint_string = NULL;
8159
8160         if (!(*conf->check_hook) (newval, extra, source))
8161         {
8162                 ereport(elevel,
8163                                 (errcode(GUC_check_errcode_value),
8164                                  GUC_check_errmsg_string ?
8165                                  errmsg_internal("%s", GUC_check_errmsg_string) :
8166                                  errmsg("invalid value for parameter \"%s\": \"%s\"",
8167                                                 conf->gen.name, *newval ? *newval : ""),
8168                                  GUC_check_errdetail_string ?
8169                                  errdetail_internal("%s", GUC_check_errdetail_string) : 0,
8170                                  GUC_check_errhint_string ?
8171                                  errhint("%s", GUC_check_errhint_string) : 0));
8172                 /* Flush any strings created in ErrorContext */
8173                 FlushErrorState();
8174                 return false;
8175         }
8176
8177         return true;
8178 }
8179
8180 static bool
8181 call_enum_check_hook(struct config_enum * conf, int *newval, void **extra,
8182                                          GucSource source, int elevel)
8183 {
8184         /* Quick success if no hook */
8185         if (!conf->check_hook)
8186                 return true;
8187
8188         /* Reset variables that might be set by hook */
8189         GUC_check_errcode_value = ERRCODE_INVALID_PARAMETER_VALUE;
8190         GUC_check_errmsg_string = NULL;
8191         GUC_check_errdetail_string = NULL;
8192         GUC_check_errhint_string = NULL;
8193
8194         if (!(*conf->check_hook) (newval, extra, source))
8195         {
8196                 ereport(elevel,
8197                                 (errcode(GUC_check_errcode_value),
8198                                  GUC_check_errmsg_string ?
8199                                  errmsg_internal("%s", GUC_check_errmsg_string) :
8200                                  errmsg("invalid value for parameter \"%s\": \"%s\"",
8201                                                 conf->gen.name,
8202                                                 config_enum_lookup_by_value(conf, *newval)),
8203                                  GUC_check_errdetail_string ?
8204                                  errdetail_internal("%s", GUC_check_errdetail_string) : 0,
8205                                  GUC_check_errhint_string ?
8206                                  errhint("%s", GUC_check_errhint_string) : 0));
8207                 /* Flush any strings created in ErrorContext */
8208                 FlushErrorState();
8209                 return false;
8210         }
8211
8212         return true;
8213 }
8214
8215
8216 /*
8217  * check_hook, assign_hook and show_hook subroutines
8218  */
8219
8220 static bool
8221 check_log_destination(char **newval, void **extra, GucSource source)
8222 {
8223         char       *rawstring;
8224         List       *elemlist;
8225         ListCell   *l;
8226         int                     newlogdest = 0;
8227         int                *myextra;
8228
8229         /* Need a modifiable copy of string */
8230         rawstring = pstrdup(*newval);
8231
8232         /* Parse string into list of identifiers */
8233         if (!SplitIdentifierString(rawstring, ',', &elemlist))
8234         {
8235                 /* syntax error in list */
8236                 GUC_check_errdetail("List syntax is invalid.");
8237                 pfree(rawstring);
8238                 list_free(elemlist);
8239                 return false;
8240         }
8241
8242         foreach(l, elemlist)
8243         {
8244                 char       *tok = (char *) lfirst(l);
8245
8246                 if (pg_strcasecmp(tok, "stderr") == 0)
8247                         newlogdest |= LOG_DESTINATION_STDERR;
8248                 else if (pg_strcasecmp(tok, "csvlog") == 0)
8249                         newlogdest |= LOG_DESTINATION_CSVLOG;
8250 #ifdef HAVE_SYSLOG
8251                 else if (pg_strcasecmp(tok, "syslog") == 0)
8252                         newlogdest |= LOG_DESTINATION_SYSLOG;
8253 #endif
8254 #ifdef WIN32
8255                 else if (pg_strcasecmp(tok, "eventlog") == 0)
8256                         newlogdest |= LOG_DESTINATION_EVENTLOG;
8257 #endif
8258                 else
8259                 {
8260                         GUC_check_errdetail("Unrecognized key word: \"%s\".", tok);
8261                         pfree(rawstring);
8262                         list_free(elemlist);
8263                         return false;
8264                 }
8265         }
8266
8267         pfree(rawstring);
8268         list_free(elemlist);
8269
8270         myextra = (int *) guc_malloc(ERROR, sizeof(int));
8271         *myextra = newlogdest;
8272         *extra = (void *) myextra;
8273
8274         return true;
8275 }
8276
8277 static void
8278 assign_log_destination(const char *newval, void *extra)
8279 {
8280         Log_destination = *((int *) extra);
8281 }
8282
8283 static void
8284 assign_syslog_facility(int newval, void *extra)
8285 {
8286 #ifdef HAVE_SYSLOG
8287         set_syslog_parameters(syslog_ident_str ? syslog_ident_str : "postgres",
8288                                                   newval);
8289 #endif
8290         /* Without syslog support, just ignore it */
8291 }
8292
8293 static void
8294 assign_syslog_ident(const char *newval, void *extra)
8295 {
8296 #ifdef HAVE_SYSLOG
8297         set_syslog_parameters(newval, syslog_facility);
8298 #endif
8299         /* Without syslog support, it will always be set to "none", so ignore */
8300 }
8301
8302
8303 static void
8304 assign_session_replication_role(int newval, void *extra)
8305 {
8306         /*
8307          * Must flush the plan cache when changing replication role; but don't
8308          * flush unnecessarily.
8309          */
8310         if (SessionReplicationRole != newval)
8311                 ResetPlanCache();
8312 }
8313
8314 static bool
8315 check_temp_buffers(int *newval, void **extra, GucSource source)
8316 {
8317         /*
8318          * Once local buffers have been initialized, it's too late to change this.
8319          */
8320         if (NLocBuffer && NLocBuffer != *newval)
8321         {
8322                 GUC_check_errdetail("\"temp_buffers\" cannot be changed after any temporary tables have been accessed in the session.");
8323                 return false;
8324         }
8325         return true;
8326 }
8327
8328 static bool
8329 check_phony_autocommit(bool *newval, void **extra, GucSource source)
8330 {
8331         if (!*newval)
8332         {
8333                 GUC_check_errcode(ERRCODE_FEATURE_NOT_SUPPORTED);
8334                 GUC_check_errmsg("SET AUTOCOMMIT TO OFF is no longer supported");
8335                 return false;
8336         }
8337         return true;
8338 }
8339
8340 static bool
8341 check_debug_assertions(bool *newval, void **extra, GucSource source)
8342 {
8343 #ifndef USE_ASSERT_CHECKING
8344         if (*newval)
8345         {
8346                 GUC_check_errmsg("assertion checking is not supported by this build");
8347                 return false;
8348         }
8349 #endif
8350         return true;
8351 }
8352
8353 static bool
8354 check_bonjour(bool *newval, void **extra, GucSource source)
8355 {
8356 #ifndef USE_BONJOUR
8357         if (*newval)
8358         {
8359                 GUC_check_errmsg("Bonjour is not supported by this build");
8360                 return false;
8361         }
8362 #endif
8363         return true;
8364 }
8365
8366 static bool
8367 check_ssl(bool *newval, void **extra, GucSource source)
8368 {
8369 #ifndef USE_SSL
8370         if (*newval)
8371         {
8372                 GUC_check_errmsg("SSL is not supported by this build");
8373                 return false;
8374         }
8375 #endif
8376         return true;
8377 }
8378
8379 static bool
8380 check_stage_log_stats(bool *newval, void **extra, GucSource source)
8381 {
8382         if (*newval && log_statement_stats)
8383         {
8384                 GUC_check_errdetail("Cannot enable parameter when \"log_statement_stats\" is true.");
8385                 return false;
8386         }
8387         return true;
8388 }
8389
8390 static bool
8391 check_log_stats(bool *newval, void **extra, GucSource source)
8392 {
8393         if (*newval &&
8394                 (log_parser_stats || log_planner_stats || log_executor_stats))
8395         {
8396                 GUC_check_errdetail("Cannot enable \"log_statement_stats\" when "
8397                                                         "\"log_parser_stats\", \"log_planner_stats\", "
8398                                                         "or \"log_executor_stats\" is true.");
8399                 return false;
8400         }
8401         return true;
8402 }
8403
8404 static bool
8405 check_canonical_path(char **newval, void **extra, GucSource source)
8406 {
8407         /*
8408          * Since canonicalize_path never enlarges the string, we can just modify
8409          * newval in-place.  But watch out for NULL, which is the default value
8410          * for external_pid_file.
8411          */
8412         if (*newval)
8413                 canonicalize_path(*newval);
8414         return true;
8415 }
8416
8417 static bool
8418 check_timezone_abbreviations(char **newval, void **extra, GucSource source)
8419 {
8420         /*
8421          * The boot_val given above for timezone_abbreviations is NULL. When we
8422          * see this we just do nothing.  If this value isn't overridden from the
8423          * config file then pg_timezone_abbrev_initialize() will eventually
8424          * replace it with "Default".  This hack has two purposes: to avoid
8425          * wasting cycles loading values that might soon be overridden from the
8426          * config file, and to avoid trying to read the timezone abbrev files
8427          * during InitializeGUCOptions().  The latter doesn't work in an
8428          * EXEC_BACKEND subprocess because my_exec_path hasn't been set yet and so
8429          * we can't locate PGSHAREDIR.
8430          */
8431         if (*newval == NULL)
8432         {
8433                 Assert(source == PGC_S_DEFAULT);
8434                 return true;
8435         }
8436
8437         /* OK, load the file and produce a malloc'd TimeZoneAbbrevTable */
8438         *extra = load_tzoffsets(*newval);
8439
8440         /* tzparser.c returns NULL on failure, reporting via GUC_check_errmsg */
8441         if (!*extra)
8442                 return false;
8443
8444         return true;
8445 }
8446
8447 static void
8448 assign_timezone_abbreviations(const char *newval, void *extra)
8449 {
8450         /* Do nothing for the boot_val default of NULL */
8451         if (!extra)
8452                 return;
8453
8454         InstallTimeZoneAbbrevs((TimeZoneAbbrevTable *) extra);
8455 }
8456
8457 /*
8458  * pg_timezone_abbrev_initialize --- set default value if not done already
8459  *
8460  * This is called after initial loading of postgresql.conf.  If no
8461  * timezone_abbreviations setting was found therein, select default.
8462  * If a non-default value is already installed, nothing will happen.
8463  *
8464  * This can also be called from ProcessConfigFile to establish the default
8465  * value after a postgresql.conf entry for it is removed.
8466  */
8467 static void
8468 pg_timezone_abbrev_initialize(void)
8469 {
8470         SetConfigOption("timezone_abbreviations", "Default",
8471                                         PGC_POSTMASTER, PGC_S_DYNAMIC_DEFAULT);
8472 }
8473
8474 static const char *
8475 show_archive_command(void)
8476 {
8477         if (XLogArchivingActive())
8478                 return XLogArchiveCommand;
8479         else
8480                 return "(disabled)";
8481 }
8482
8483 static void
8484 assign_tcp_keepalives_idle(int newval, void *extra)
8485 {
8486         /*
8487          * The kernel API provides no way to test a value without setting it; and
8488          * once we set it we might fail to unset it.  So there seems little point
8489          * in fully implementing the check-then-assign GUC API for these
8490          * variables.  Instead we just do the assignment on demand.  pqcomm.c
8491          * reports any problems via elog(LOG).
8492          *
8493          * This approach means that the GUC value might have little to do with the
8494          * actual kernel value, so we use a show_hook that retrieves the kernel
8495          * value rather than trusting GUC's copy.
8496          */
8497         (void) pq_setkeepalivesidle(newval, MyProcPort);
8498 }
8499
8500 static const char *
8501 show_tcp_keepalives_idle(void)
8502 {
8503         /* See comments in assign_tcp_keepalives_idle */
8504         static char nbuf[16];
8505
8506         snprintf(nbuf, sizeof(nbuf), "%d", pq_getkeepalivesidle(MyProcPort));
8507         return nbuf;
8508 }
8509
8510 static void
8511 assign_tcp_keepalives_interval(int newval, void *extra)
8512 {
8513         /* See comments in assign_tcp_keepalives_idle */
8514         (void) pq_setkeepalivesinterval(newval, MyProcPort);
8515 }
8516
8517 static const char *
8518 show_tcp_keepalives_interval(void)
8519 {
8520         /* See comments in assign_tcp_keepalives_idle */
8521         static char nbuf[16];
8522
8523         snprintf(nbuf, sizeof(nbuf), "%d", pq_getkeepalivesinterval(MyProcPort));
8524         return nbuf;
8525 }
8526
8527 static void
8528 assign_tcp_keepalives_count(int newval, void *extra)
8529 {
8530         /* See comments in assign_tcp_keepalives_idle */
8531         (void) pq_setkeepalivescount(newval, MyProcPort);
8532 }
8533
8534 static const char *
8535 show_tcp_keepalives_count(void)
8536 {
8537         /* See comments in assign_tcp_keepalives_idle */
8538         static char nbuf[16];
8539
8540         snprintf(nbuf, sizeof(nbuf), "%d", pq_getkeepalivescount(MyProcPort));
8541         return nbuf;
8542 }
8543
8544 static bool
8545 check_maxconnections(int *newval, void **extra, GucSource source)
8546 {
8547         if (*newval + autovacuum_max_workers + 1 > MAX_BACKENDS)
8548                 return false;
8549         return true;
8550 }
8551
8552 static void
8553 assign_maxconnections(int newval, void *extra)
8554 {
8555         MaxBackends = newval + autovacuum_max_workers + 1;
8556 }
8557
8558 static bool
8559 check_autovacuum_max_workers(int *newval, void **extra, GucSource source)
8560 {
8561         if (MaxConnections + *newval + 1 > MAX_BACKENDS)
8562                 return false;
8563         return true;
8564 }
8565
8566 static void
8567 assign_autovacuum_max_workers(int newval, void *extra)
8568 {
8569         MaxBackends = MaxConnections + newval + 1;
8570 }
8571
8572 static bool
8573 check_effective_io_concurrency(int *newval, void **extra, GucSource source)
8574 {
8575 #ifdef USE_PREFETCH
8576         double          new_prefetch_pages = 0.0;
8577         int                     i;
8578
8579         /*----------
8580          * The user-visible GUC parameter is the number of drives (spindles),
8581          * which we need to translate to a number-of-pages-to-prefetch target.
8582          * The target value is stashed in *extra and then assigned to the actual
8583          * variable by assign_effective_io_concurrency.
8584          *
8585          * The expected number of prefetch pages needed to keep N drives busy is:
8586          *
8587          * drives |   I/O requests
8588          * -------+----------------
8589          *              1 |   1
8590          *              2 |   2/1 + 2/2 = 3
8591          *              3 |   3/1 + 3/2 + 3/3 = 5 1/2
8592          *              4 |   4/1 + 4/2 + 4/3 + 4/4 = 8 1/3
8593          *              n |   n * H(n)
8594          *
8595          * This is called the "coupon collector problem" and H(n) is called the
8596          * harmonic series.  This could be approximated by n * ln(n), but for
8597          * reasonable numbers of drives we might as well just compute the series.
8598          *
8599          * Alternatively we could set the target to the number of pages necessary
8600          * so that the expected number of active spindles is some arbitrary
8601          * percentage of the total.  This sounds the same but is actually slightly
8602          * different.  The result ends up being ln(1-P)/ln((n-1)/n) where P is
8603          * that desired fraction.
8604          *
8605          * Experimental results show that both of these formulas aren't aggressive
8606          * enough, but we don't really have any better proposals.
8607          *
8608          * Note that if *newval = 0 (disabled), we must set target = 0.
8609          *----------
8610          */
8611
8612         for (i = 1; i <= *newval; i++)
8613                 new_prefetch_pages += (double) *newval / (double) i;
8614
8615         /* This range check shouldn't fail, but let's be paranoid */
8616         if (new_prefetch_pages >= 0.0 && new_prefetch_pages < (double) INT_MAX)
8617         {
8618                 int                *myextra = (int *) guc_malloc(ERROR, sizeof(int));
8619
8620                 *myextra = (int) rint(new_prefetch_pages);
8621                 *extra = (void *) myextra;
8622
8623                 return true;
8624         }
8625         else
8626                 return false;
8627 #else
8628         return true;
8629 #endif   /* USE_PREFETCH */
8630 }
8631
8632 static void
8633 assign_effective_io_concurrency(int newval, void *extra)
8634 {
8635 #ifdef USE_PREFETCH
8636         target_prefetch_pages = *((int *) extra);
8637 #endif   /* USE_PREFETCH */
8638 }
8639
8640 static void
8641 assign_pgstat_temp_directory(const char *newval, void *extra)
8642 {
8643         /* check_canonical_path already canonicalized newval for us */
8644         char       *tname;
8645         char       *fname;
8646
8647         tname = guc_malloc(ERROR, strlen(newval) + 12);         /* /pgstat.tmp */
8648         sprintf(tname, "%s/pgstat.tmp", newval);
8649         fname = guc_malloc(ERROR, strlen(newval) + 13);         /* /pgstat.stat */
8650         sprintf(fname, "%s/pgstat.stat", newval);
8651
8652         if (pgstat_stat_tmpname)
8653                 free(pgstat_stat_tmpname);
8654         pgstat_stat_tmpname = tname;
8655         if (pgstat_stat_filename)
8656                 free(pgstat_stat_filename);
8657         pgstat_stat_filename = fname;
8658 }
8659
8660 static bool
8661 check_application_name(char **newval, void **extra, GucSource source)
8662 {
8663         /* Only allow clean ASCII chars in the application name */
8664         char       *p;
8665
8666         for (p = *newval; *p; p++)
8667         {
8668                 if (*p < 32 || *p > 126)
8669                         *p = '?';
8670         }
8671
8672         return true;
8673 }
8674
8675 static void
8676 assign_application_name(const char *newval, void *extra)
8677 {
8678         /* Update the pg_stat_activity view */
8679         pgstat_report_appname(newval);
8680 }
8681
8682 static const char *
8683 show_unix_socket_permissions(void)
8684 {
8685         static char buf[8];
8686
8687         snprintf(buf, sizeof(buf), "%04o", Unix_socket_permissions);
8688         return buf;
8689 }
8690
8691 static const char *
8692 show_log_file_mode(void)
8693 {
8694         static char buf[8];
8695
8696         snprintf(buf, sizeof(buf), "%04o", Log_file_mode);
8697         return buf;
8698 }
8699
8700 #include "guc-file.c"