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) 2000-2007, PostgreSQL Global Development Group
  10  * Written by Peter Eisentraut <peter_e@gmx.net>.
  11  *
  12  * IDENTIFICATION
  13  *        $PostgreSQL: pgsql/src/backend/utils/misc/guc.c,v 1.411 2007/08/08 16:00:46 tgl Exp $
  14  *
  15  *--------------------------------------------------------------------
  16  */
  17 #include "postgres.h"
  18
  19 #include <ctype.h>
  20 #include <float.h>
  21 #include <limits.h>
  22 #include <unistd.h>
  23 #include <sys/stat.h>
  24 #ifdef HAVE_SYSLOG
  25 #include <syslog.h>
  26 #endif
  27
  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/pqformat.h"
  42 #include "miscadmin.h"
  43 #include "optimizer/cost.h"
  44 #include "optimizer/geqo.h"
  45 #include "optimizer/paths.h"
  46 #include "optimizer/planmain.h"
  47 #include "parser/gramparse.h"
  48 #include "parser/parse_expr.h"
  49 #include "parser/parse_relation.h"
  50 #include "parser/parse_type.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 "storage/fd.h"
  59 #include "storage/freespace.h"
  60 #include "tcop/tcopprot.h"
  61 #include "utils/builtins.h"
  62 #include "utils/guc_tables.h"
  63 #include "utils/memutils.h"
  64 #include "utils/pg_locale.h"
  65 #include "utils/plancache.h"
  66 #include "utils/portal.h"
  67 #include "utils/ps_status.h"
  68 #include "utils/tzparser.h"
  69 #include "utils/xml.h"
  70
  71 #ifndef PG_KRB_SRVTAB
  72 #define PG_KRB_SRVTAB ""
  73 #endif
  74 #ifndef PG_KRB_SRVNAM
  75 #define PG_KRB_SRVNAM ""
  76 #endif
  77
  78 #define CONFIG_FILENAME "postgresql.conf"
  79 #define HBA_FILENAME    "pg_hba.conf"
  80 #define IDENT_FILENAME  "pg_ident.conf"
  81
  82 #ifdef EXEC_BACKEND
  83 #define CONFIG_EXEC_PARAMS "global/config_exec_params"
  84 #define CONFIG_EXEC_PARAMS_NEW "global/config_exec_params.new"
  85 #endif
  86
  87 /* upper limit for GUC variables measured in kilobytes of memory */
  88 #if SIZEOF_SIZE_T > 4
  89 #define MAX_KILOBYTES   INT_MAX
  90 #else
  91 #define MAX_KILOBYTES   (INT_MAX / 1024)
  92 #endif
  93
  94 #define KB_PER_MB (1024)
  95 #define KB_PER_GB (1024*1024)
  96
  97 #define MS_PER_S 1000
  98 #define S_PER_MIN 60
  99 #define MS_PER_MIN (1000 * 60)
 100 #define MIN_PER_H 60
 101 #define S_PER_H (60 * 60)
 102 #define MS_PER_H (1000 * 60 * 60)
 103 #define MIN_PER_D (60 * 24)
 104 #define S_PER_D (60 * 60 * 24)
 105 #define MS_PER_D (1000 * 60 * 60 * 24)
 106
 107 /* XXX these should appear in other modules' header files */
 108 extern bool Log_disconnections;
 109 extern int      CommitDelay;
 110 extern int      CommitSiblings;
 111 extern char *default_tablespace;
 112 extern char *temp_tablespaces;
 113 extern bool fullPageWrites;
 114
 115 #ifdef TRACE_SORT
 116 extern bool trace_sort;
 117 #endif
 118 #ifdef TRACE_SYNCSCAN
 119 extern bool trace_syncscan;
 120 #endif
 121 #ifdef DEBUG_BOUNDED_SORT
 122 extern bool optimize_bounded_sort;
 123 #endif
 124
 125 #ifdef USE_SSL
 126 extern char *SSLCipherSuites;
 127 #endif
 128
 129
 130 static const char *assign_log_destination(const char *value,
 131                                            bool doit, GucSource source);
 132
 133 #ifdef HAVE_SYSLOG
 134 static int      syslog_facility = LOG_LOCAL0;
 135
 136 static const char *assign_syslog_facility(const char *facility,
 137                                            bool doit, GucSource source);
 138 static const char *assign_syslog_ident(const char *ident,
 139                                         bool doit, GucSource source);
 140 #endif
 141
 142 static const char *assign_defaultxactisolevel(const char *newval, bool doit,
 143                                                    GucSource source);
 144 static const char *assign_session_replication_role(const char *newval, bool doit,
 145                                                    GucSource source);
 146 static const char *assign_log_min_messages(const char *newval, bool doit,
 147                                                 GucSource source);
 148 static const char *assign_client_min_messages(const char *newval,
 149                                                    bool doit, GucSource source);
 150 static const char *assign_min_error_statement(const char *newval, bool doit,
 151                                                    GucSource source);
 152 static const char *assign_msglvl(int *var, const char *newval, bool doit,
 153                           GucSource source);
 154 static const char *assign_log_error_verbosity(const char *newval, bool doit,
 155                                                    GucSource source);
 156 static const char *assign_log_statement(const char *newval, bool doit,
 157                                          GucSource source);
 158 static const char *show_num_temp_buffers(void);
 159 static bool assign_phony_autocommit(bool newval, bool doit, GucSource source);
 160 static const char *assign_custom_variable_classes(const char *newval, bool doit,
 161                                                            GucSource source);
 162 static bool assign_debug_assertions(bool newval, bool doit, GucSource source);
 163 static bool assign_ssl(bool newval, bool doit, GucSource source);
 164 static bool assign_stage_log_stats(bool newval, bool doit, GucSource source);
 165 static bool assign_log_stats(bool newval, bool doit, GucSource source);
 166 static bool assign_transaction_read_only(bool newval, bool doit, GucSource source);
 167 static const char *assign_canonical_path(const char *newval, bool doit, GucSource source);
 168 static const char *assign_backslash_quote(const char *newval, bool doit, GucSource source);
 169 static const char *assign_timezone_abbreviations(const char *newval, bool doit, GucSource source);
 170 static const char *assign_xmlbinary(const char *newval, bool doit, GucSource source);
 171 static const char *assign_xmloption(const char *newval, bool doit, GucSource source);
 172
 173 static bool assign_tcp_keepalives_idle(int newval, bool doit, GucSource source);
 174 static bool assign_tcp_keepalives_interval(int newval, bool doit, GucSource source);
 175 static bool assign_tcp_keepalives_count(int newval, bool doit, GucSource source);
 176 static const char *show_tcp_keepalives_idle(void);
 177 static const char *show_tcp_keepalives_interval(void);
 178 static const char *show_tcp_keepalives_count(void);
 179 static bool assign_autovacuum_max_workers(int newval, bool doit, GucSource source);
 180 static bool assign_maxconnections(int newval, bool doit, GucSource source);
 181
 182 /*
 183  * GUC option variables that are exported from this module
 184  */
 185 #ifdef USE_ASSERT_CHECKING
 186 bool            assert_enabled = true;
 187 #else
 188 bool            assert_enabled = false;
 189 #endif
 190 bool            log_duration = false;
 191 bool            Debug_print_plan = false;
 192 bool            Debug_print_parse = false;
 193 bool            Debug_print_rewritten = false;
 194 bool            Debug_pretty_print = false;
 195 bool            Explain_pretty_print = true;
 196
 197 bool            log_parser_stats = false;
 198 bool            log_planner_stats = false;
 199 bool            log_executor_stats = false;
 200 bool            log_statement_stats = false;            /* this is sort of all three
 201                                                                                                  * above together */
 202 bool            log_btree_build_stats = false;
 203
 204 bool            check_function_bodies = true;
 205 bool            default_with_oids = false;
 206 bool            SQL_inheritance = true;
 207
 208 bool            Password_encryption = true;
 209
 210 int                     log_min_error_statement = ERROR;
 211 int                     log_min_messages = NOTICE;
 212 int                     client_min_messages = NOTICE;
 213 int                     log_min_duration_statement = -1;
 214 int                     log_temp_files = -1;
 215
 216 int                     num_temp_buffers = 1000;
 217
 218 char       *ConfigFileName;
 219 char       *HbaFileName;
 220 char       *IdentFileName;
 221 char       *external_pid_file;
 222
 223 int                     tcp_keepalives_idle;
 224 int                     tcp_keepalives_interval;
 225 int                     tcp_keepalives_count;
 226
 227 /*
 228  * These variables are all dummies that don't do anything, except in some
 229  * cases provide the value for SHOW to display.  The real state is elsewhere
 230  * and is kept in sync by assign_hooks.
 231  */
 232 static char *client_min_messages_str;
 233 static char *log_min_messages_str;
 234 static char *log_error_verbosity_str;
 235 static char *log_statement_str;
 236 static char *log_min_error_statement_str;
 237 static char *log_destination_string;
 238
 239 #ifdef HAVE_SYSLOG
 240 static char *syslog_facility_str;
 241 static char *syslog_ident_str;
 242 #endif
 243 static bool phony_autocommit;
 244 static bool session_auth_is_superuser;
 245 static double phony_random_seed;
 246 static char *backslash_quote_string;
 247 static char *client_encoding_string;
 248 static char *datestyle_string;
 249 static char *default_iso_level_string;
 250 static char *session_replication_role_string;
 251 static char *locale_collate;
 252 static char *locale_ctype;
 253 static char *regex_flavor_string;
 254 static char *server_encoding_string;
 255 static char *server_version_string;
 256 static int      server_version_num;
 257 static char *timezone_string;
 258 static char *log_timezone_string;
 259 static char *timezone_abbreviations_string;
 260 static char *XactIsoLevel_string;
 261 static char *data_directory;
 262 static char *custom_variable_classes;
 263 static char *xmlbinary_string;
 264 static char *xmloption_string;
 265 static int      max_function_args;
 266 static int      max_index_keys;
 267 static int      max_identifier_length;
 268 static int      block_size;
 269 static bool integer_datetimes;
 270
 271 /* should be static, but commands/variable.c needs to get at these */
 272 char       *role_string;
 273 char       *session_authorization_string;
 274
 275
 276 /*
 277  * Displayable names for context types (enum GucContext)
 278  *
 279  * Note: these strings are deliberately not localized.
 280  */
 281 const char *const GucContext_Names[] =
 282 {
 283          /* PGC_INTERNAL */ "internal",
 284          /* PGC_POSTMASTER */ "postmaster",
 285          /* PGC_SIGHUP */ "sighup",
 286          /* PGC_BACKEND */ "backend",
 287          /* PGC_SUSET */ "superuser",
 288          /* PGC_USERSET */ "user"
 289 };
 290
 291 /*
 292  * Displayable names for source types (enum GucSource)
 293  *
 294  * Note: these strings are deliberately not localized.
 295  */
 296 const char *const GucSource_Names[] =
 297 {
 298          /* PGC_S_DEFAULT */ "default",
 299          /* PGC_S_ENV_VAR */ "environment variable",
 300          /* PGC_S_FILE */ "configuration file",
 301          /* PGC_S_ARGV */ "command line",
 302          /* PGC_S_DATABASE */ "database",
 303          /* PGC_S_USER */ "user",
 304          /* PGC_S_CLIENT */ "client",
 305          /* PGC_S_OVERRIDE */ "override",
 306          /* PGC_S_INTERACTIVE */ "interactive",
 307          /* PGC_S_TEST */ "test",
 308          /* PGC_S_SESSION */ "session"
 309 };
 310
 311 /*
 312  * Displayable names for the groupings defined in enum config_group
 313  */
 314 const char *const config_group_names[] =
 315 {
 316         /* UNGROUPED */
 317         gettext_noop("Ungrouped"),
 318         /* FILE_LOCATIONS */
 319         gettext_noop("File Locations"),
 320         /* CONN_AUTH */
 321         gettext_noop("Connections and Authentication"),
 322         /* CONN_AUTH_SETTINGS */
 323         gettext_noop("Connections and Authentication / Connection Settings"),
 324         /* CONN_AUTH_SECURITY */
 325         gettext_noop("Connections and Authentication / Security and Authentication"),
 326         /* RESOURCES */
 327         gettext_noop("Resource Usage"),
 328         /* RESOURCES_MEM */
 329         gettext_noop("Resource Usage / Memory"),
 330         /* RESOURCES_FSM */
 331         gettext_noop("Resource Usage / Free Space Map"),
 332         /* RESOURCES_KERNEL */
 333         gettext_noop("Resource Usage / Kernel Resources"),
 334         /* WAL */
 335         gettext_noop("Write-Ahead Log"),
 336         /* WAL_SETTINGS */
 337         gettext_noop("Write-Ahead Log / Settings"),
 338         /* WAL_CHECKPOINTS */
 339         gettext_noop("Write-Ahead Log / Checkpoints"),
 340         /* QUERY_TUNING */
 341         gettext_noop("Query Tuning"),
 342         /* QUERY_TUNING_METHOD */
 343         gettext_noop("Query Tuning / Planner Method Configuration"),
 344         /* QUERY_TUNING_COST */
 345         gettext_noop("Query Tuning / Planner Cost Constants"),
 346         /* QUERY_TUNING_GEQO */
 347         gettext_noop("Query Tuning / Genetic Query Optimizer"),
 348         /* QUERY_TUNING_OTHER */
 349         gettext_noop("Query Tuning / Other Planner Options"),
 350         /* LOGGING */
 351         gettext_noop("Reporting and Logging"),
 352         /* LOGGING_WHERE */
 353         gettext_noop("Reporting and Logging / Where to Log"),
 354         /* LOGGING_WHEN */
 355         gettext_noop("Reporting and Logging / When to Log"),
 356         /* LOGGING_WHAT */
 357         gettext_noop("Reporting and Logging / What to Log"),
 358         /* STATS */
 359         gettext_noop("Statistics"),
 360         /* STATS_MONITORING */
 361         gettext_noop("Statistics / Monitoring"),
 362         /* STATS_COLLECTOR */
 363         gettext_noop("Statistics / Query and Index Statistics Collector"),
 364         /* AUTOVACUUM */
 365         gettext_noop("Autovacuum"),
 366         /* CLIENT_CONN */
 367         gettext_noop("Client Connection Defaults"),
 368         /* CLIENT_CONN_STATEMENT */
 369         gettext_noop("Client Connection Defaults / Statement Behavior"),
 370         /* CLIENT_CONN_LOCALE */
 371         gettext_noop("Client Connection Defaults / Locale and Formatting"),
 372         /* CLIENT_CONN_OTHER */
 373         gettext_noop("Client Connection Defaults / Other Defaults"),
 374         /* LOCK_MANAGEMENT */
 375         gettext_noop("Lock Management"),
 376         /* COMPAT_OPTIONS */
 377         gettext_noop("Version and Platform Compatibility"),
 378         /* COMPAT_OPTIONS_PREVIOUS */
 379         gettext_noop("Version and Platform Compatibility / Previous PostgreSQL Versions"),
 380         /* COMPAT_OPTIONS_CLIENT */
 381         gettext_noop("Version and Platform Compatibility / Other Platforms and Clients"),
 382         /* PRESET_OPTIONS */
 383         gettext_noop("Preset Options"),
 384         /* CUSTOM_OPTIONS */
 385         gettext_noop("Customized Options"),
 386         /* DEVELOPER_OPTIONS */
 387         gettext_noop("Developer Options"),
 388         /* help_config wants this array to be null-terminated */
 389         NULL
 390 };
 391
 392 /*
 393  * Displayable names for GUC variable types (enum config_type)
 394  *
 395  * Note: these strings are deliberately not localized.
 396  */
 397 const char *const config_type_names[] =
 398 {
 399          /* PGC_BOOL */ "bool",
 400          /* PGC_INT */ "integer",
 401          /* PGC_REAL */ "real",
 402          /* PGC_STRING */ "string"
 403 };
 404
 405
 406 /*
 407  * Contents of GUC tables
 408  *
 409  * See src/backend/utils/misc/README for design notes.
 410  *
 411  * TO ADD AN OPTION:
 412  *
 413  * 1. Declare a global variable of type bool, int, double, or char*
 414  *        and make use of it.
 415  *
 416  * 2. Decide at what times it's safe to set the option. See guc.h for
 417  *        details.
 418  *
 419  * 3. Decide on a name, a default value, upper and lower bounds (if
 420  *        applicable), etc.
 421  *
 422  * 4. Add a record below.
 423  *
 424  * 5. Add it to src/backend/utils/misc/postgresql.conf.sample, if
 425  *        appropriate
 426  *
 427  * 6. Don't forget to document the option.
 428  *
 429  * 7. If it's a new GUC_LIST option you must edit pg_dumpall.c to ensure
 430  *        it is not single quoted at dump time.
 431  */
 432
 433
 434 /******** option records follow ********/
 435
 436 static struct config_bool ConfigureNamesBool[] =
 437 {
 438         {
 439                 {"enable_seqscan", PGC_USERSET, QUERY_TUNING_METHOD,
 440                         gettext_noop("Enables the planner's use of sequential-scan plans."),
 441                         NULL
 442                 },
 443                 &enable_seqscan,
 444                 true, NULL, NULL
 445         },
 446         {
 447                 {"enable_indexscan", PGC_USERSET, QUERY_TUNING_METHOD,
 448                         gettext_noop("Enables the planner's use of index-scan plans."),
 449                         NULL
 450                 },
 451                 &enable_indexscan,
 452                 true, NULL, NULL
 453         },
 454         {
 455                 {"enable_bitmapscan", PGC_USERSET, QUERY_TUNING_METHOD,
 456                         gettext_noop("Enables the planner's use of bitmap-scan plans."),
 457                         NULL
 458                 },
 459                 &enable_bitmapscan,
 460                 true, NULL, NULL
 461         },
 462         {
 463                 {"enable_tidscan", PGC_USERSET, QUERY_TUNING_METHOD,
 464                         gettext_noop("Enables the planner's use of TID scan plans."),
 465                         NULL
 466                 },
 467                 &enable_tidscan,
 468                 true, NULL, NULL
 469         },
 470         {
 471                 {"enable_sort", PGC_USERSET, QUERY_TUNING_METHOD,
 472                         gettext_noop("Enables the planner's use of explicit sort steps."),
 473                         NULL
 474                 },
 475                 &enable_sort,
 476                 true, NULL, NULL
 477         },
 478         {
 479                 {"enable_hashagg", PGC_USERSET, QUERY_TUNING_METHOD,
 480                         gettext_noop("Enables the planner's use of hashed aggregation plans."),
 481                         NULL
 482                 },
 483                 &enable_hashagg,
 484                 true, NULL, NULL
 485         },
 486         {
 487                 {"enable_nestloop", PGC_USERSET, QUERY_TUNING_METHOD,
 488                         gettext_noop("Enables the planner's use of nested-loop join plans."),
 489                         NULL
 490                 },
 491                 &enable_nestloop,
 492                 true, NULL, NULL
 493         },
 494         {
 495                 {"enable_mergejoin", PGC_USERSET, QUERY_TUNING_METHOD,
 496                         gettext_noop("Enables the planner's use of merge join plans."),
 497                         NULL
 498                 },
 499                 &enable_mergejoin,
 500                 true, NULL, NULL
 501         },
 502         {
 503                 {"enable_hashjoin", PGC_USERSET, QUERY_TUNING_METHOD,
 504                         gettext_noop("Enables the planner's use of hash join plans."),
 505                         NULL
 506                 },
 507                 &enable_hashjoin,
 508                 true, NULL, NULL
 509         },
 510         {
 511                 {"constraint_exclusion", PGC_USERSET, QUERY_TUNING_OTHER,
 512                         gettext_noop("Enables the planner to use constraints to optimize queries."),
 513                         gettext_noop("Child table scans will be skipped if their "
 514                                            "constraints guarantee that no rows match the query.")
 515                 },
 516                 &constraint_exclusion,
 517                 false, NULL, NULL
 518         },
 519         {
 520                 {"geqo", PGC_USERSET, QUERY_TUNING_GEQO,
 521                         gettext_noop("Enables genetic query optimization."),
 522                         gettext_noop("This algorithm attempts to do planning without "
 523                                                  "exhaustive searching.")
 524                 },
 525                 &enable_geqo,
 526                 true, NULL, NULL
 527         },
 528         {
 529                 /* Not for general use --- used by SET SESSION AUTHORIZATION */
 530                 {"is_superuser", PGC_INTERNAL, UNGROUPED,
 531                         gettext_noop("Shows whether the current user is a superuser."),
 532                         NULL,
 533                         GUC_REPORT | GUC_NO_SHOW_ALL | GUC_NO_RESET_ALL | GUC_NOT_IN_SAMPLE | GUC_DISALLOW_IN_FILE
 534                 },
 535                 &session_auth_is_superuser,
 536                 false, NULL, NULL
 537         },
 538         {
 539                 {"ssl", PGC_POSTMASTER, CONN_AUTH_SECURITY,
 540                         gettext_noop("Enables SSL connections."),
 541                         NULL
 542                 },
 543                 &EnableSSL,
 544                 false, assign_ssl, NULL
 545         },
 546         {
 547                 {"fsync", PGC_SIGHUP, WAL_SETTINGS,
 548                         gettext_noop("Forces synchronization of updates to disk."),
 549                         gettext_noop("The server will use the fsync() system call in several places to make "
 550                         "sure that updates are physically written to disk. This insures "
 551                                                  "that a database cluster will recover to a consistent state after "
 552                                                  "an operating system or hardware crash.")
 553                 },
 554                 &enableFsync,
 555                 true, NULL, NULL
 556         },
 557         {
 558                 {"synchronous_commit", PGC_USERSET, WAL_SETTINGS,
 559                         gettext_noop("Sets immediate fsync at commit."),
 560                         NULL
 561                 },
 562                 &XactSyncCommit,
 563                 true, NULL, NULL
 564         },
 565         {
 566                 {"zero_damaged_pages", PGC_SUSET, DEVELOPER_OPTIONS,
 567                         gettext_noop("Continues processing past damaged page headers."),
 568                         gettext_noop("Detection of a damaged page header normally causes PostgreSQL to "
 569                                 "report an error, aborting the current transaction. Setting "
 570                                                  "zero_damaged_pages to true causes the system to instead report a "
 571                                                  "warning, zero out the damaged page, and continue processing. This "
 572                                                  "behavior will destroy data, namely all the rows on the damaged page."),
 573                         GUC_NOT_IN_SAMPLE
 574                 },
 575                 &zero_damaged_pages,
 576                 false, NULL, NULL
 577         },
 578         {
 579                 {"full_page_writes", PGC_SIGHUP, WAL_SETTINGS,
 580                         gettext_noop("Writes full pages to WAL when first modified after a checkpoint."),
 581                         gettext_noop("A page write in process during an operating system crash might be "
 582                                                  "only partially written to disk.  During recovery, the row changes "
 583                           "stored in WAL are not enough to recover.  This option writes "
 584                                                  "pages when first modified after a checkpoint to WAL so full recovery "
 585                                                  "is possible.")
 586                 },
 587                 &fullPageWrites,
 588                 true, NULL, NULL
 589         },
 590         {
 591                 {"silent_mode", PGC_POSTMASTER, LOGGING_WHEN,
 592                         gettext_noop("Runs the server silently."),
 593                         gettext_noop("If this parameter is set, the server will automatically run in the "
 594                                  "background and any controlling terminals are dissociated.")
 595                 },
 596                 &SilentMode,
 597                 false, NULL, NULL
 598         },
 599         {
 600                 {"log_checkpoints", PGC_SIGHUP, LOGGING_WHAT,
 601                         gettext_noop("Logs each checkpoint."),
 602                         NULL
 603                 },
 604                 &log_checkpoints,
 605                 false, NULL, NULL
 606         },
 607         {
 608                 {"log_connections", PGC_BACKEND, LOGGING_WHAT,
 609                         gettext_noop("Logs each successful connection."),
 610                         NULL
 611                 },
 612                 &Log_connections,
 613                 false, NULL, NULL
 614         },
 615         {
 616                 {"log_disconnections", PGC_BACKEND, LOGGING_WHAT,
 617                         gettext_noop("Logs end of a session, including duration."),
 618                         NULL
 619                 },
 620                 &Log_disconnections,
 621                 false, NULL, NULL
 622         },
 623         {
 624                 {"debug_assertions", PGC_USERSET, DEVELOPER_OPTIONS,
 625                         gettext_noop("Turns on various assertion checks."),
 626                         gettext_noop("This is a debugging aid."),
 627                         GUC_NOT_IN_SAMPLE
 628                 },
 629                 &assert_enabled,
 630 #ifdef USE_ASSERT_CHECKING
 631                 true,
 632 #else
 633                 false,
 634 #endif
 635                 assign_debug_assertions, NULL
 636         },
 637         {
 638                 /* currently undocumented, so don't show in SHOW ALL */
 639                 {"exit_on_error", PGC_USERSET, UNGROUPED,
 640                         gettext_noop("No description available."),
 641                         NULL,
 642                         GUC_NO_SHOW_ALL | GUC_NOT_IN_SAMPLE
 643                 },
 644                 &ExitOnAnyError,
 645                 false, NULL, NULL
 646         },
 647         {
 648                 {"log_duration", PGC_SUSET, LOGGING_WHAT,
 649                         gettext_noop("Logs the duration of each completed SQL statement."),
 650                         NULL
 651                 },
 652                 &log_duration,
 653                 false, NULL, NULL
 654         },
 655         {
 656                 {"debug_print_parse", PGC_USERSET, LOGGING_WHAT,
 657                         gettext_noop("Prints the parse tree to the server log."),
 658                         NULL
 659                 },
 660                 &Debug_print_parse,
 661                 false, NULL, NULL
 662         },
 663         {
 664                 {"debug_print_rewritten", PGC_USERSET, LOGGING_WHAT,
 665                         gettext_noop("Prints the parse tree after rewriting to server log."),
 666                         NULL
 667                 },
 668                 &Debug_print_rewritten,
 669                 false, NULL, NULL
 670         },
 671         {
 672                 {"debug_print_plan", PGC_USERSET, LOGGING_WHAT,
 673                         gettext_noop("Prints the execution plan to server log."),
 674                         NULL
 675                 },
 676                 &Debug_print_plan,
 677                 false, NULL, NULL
 678         },
 679         {
 680                 {"debug_pretty_print", PGC_USERSET, LOGGING_WHAT,
 681                         gettext_noop("Indents parse and plan tree displays."),
 682                         NULL
 683                 },
 684                 &Debug_pretty_print,
 685                 false, NULL, NULL
 686         },
 687         {
 688                 {"log_parser_stats", PGC_SUSET, STATS_MONITORING,
 689                         gettext_noop("Writes parser performance statistics to the server log."),
 690                         NULL
 691                 },
 692                 &log_parser_stats,
 693                 false, assign_stage_log_stats, NULL
 694         },
 695         {
 696                 {"log_planner_stats", PGC_SUSET, STATS_MONITORING,
 697                         gettext_noop("Writes planner performance statistics to the server log."),
 698                         NULL
 699                 },
 700                 &log_planner_stats,
 701                 false, assign_stage_log_stats, NULL
 702         },
 703         {
 704                 {"log_executor_stats", PGC_SUSET, STATS_MONITORING,
 705                         gettext_noop("Writes executor performance statistics to the server log."),
 706                         NULL
 707                 },
 708                 &log_executor_stats,
 709                 false, assign_stage_log_stats, NULL
 710         },
 711         {
 712                 {"log_statement_stats", PGC_SUSET, STATS_MONITORING,
 713                         gettext_noop("Writes cumulative performance statistics to the server log."),
 714                         NULL
 715                 },
 716                 &log_statement_stats,
 717                 false, assign_log_stats, NULL
 718         },
 719 #ifdef BTREE_BUILD_STATS
 720         {
 721                 {"log_btree_build_stats", PGC_SUSET, DEVELOPER_OPTIONS,
 722                         gettext_noop("No description available."),
 723                         NULL,
 724                         GUC_NOT_IN_SAMPLE
 725                 },
 726                 &log_btree_build_stats,
 727                 false, NULL, NULL
 728         },
 729 #endif
 730
 731         {
 732                 {"explain_pretty_print", PGC_USERSET, CLIENT_CONN_OTHER,
 733                         gettext_noop("Uses the indented output format for EXPLAIN VERBOSE."),
 734                         NULL
 735                 },
 736                 &Explain_pretty_print,
 737                 true, NULL, NULL
 738         },
 739         {
 740                 {"stats_start_collector", PGC_POSTMASTER, STATS_COLLECTOR,
 741                         gettext_noop("Starts the server statistics-collection subprocess."),
 742                         NULL
 743                 },
 744                 &pgstat_collect_startcollector,
 745                 true, NULL, NULL
 746         },
 747         {
 748                 {"stats_reset_on_server_start", PGC_POSTMASTER, STATS_COLLECTOR,
 749                         gettext_noop("Zeroes collected statistics on server restart."),
 750                         NULL
 751                 },
 752                 &pgstat_collect_resetonpmstart,
 753                 false, NULL, NULL
 754         },
 755         {
 756                 {"stats_row_level", PGC_SUSET, STATS_COLLECTOR,
 757                         gettext_noop("Collects row-level statistics on database activity."),
 758                         NULL
 759                 },
 760                 &pgstat_collect_tuplelevel,
 761                 true, NULL, NULL
 762         },
 763         {
 764                 {"stats_block_level", PGC_SUSET, STATS_COLLECTOR,
 765                         gettext_noop("Collects block-level statistics on database activity."),
 766                         NULL
 767                 },
 768                 &pgstat_collect_blocklevel,
 769                 false, NULL, NULL
 770         },
 771
 772         {
 773                 {"stats_command_string", PGC_SUSET, STATS_COLLECTOR,
 774                         gettext_noop("Collects information about executing commands."),
 775                         gettext_noop("Enables the collection of information on the currently "
 776                                         "executing command of each session, along with the time "
 777                                                  "at which that command began execution.")
 778                 },
 779                 &pgstat_collect_querystring,
 780                 true, NULL, NULL
 781         },
 782
 783         {
 784                 {"update_process_title", PGC_SUSET, STATS_COLLECTOR,
 785                         gettext_noop("Updates the process title to show the active SQL command."),
 786                         gettext_noop("Enables updating of the process title every time a new SQL command is received by the server.")
 787                 },
 788                 &update_process_title,
 789                 true, NULL, NULL
 790         },
 791
 792         {
 793                 {"autovacuum", PGC_SIGHUP, AUTOVACUUM,
 794                         gettext_noop("Starts the autovacuum subprocess."),
 795                         NULL
 796                 },
 797                 &autovacuum_start_daemon,
 798                 true, NULL, NULL
 799         },
 800
 801         {
 802                 {"trace_notify", PGC_USERSET, DEVELOPER_OPTIONS,
 803                         gettext_noop("Generates debugging output for LISTEN and NOTIFY."),
 804                         NULL,
 805                         GUC_NOT_IN_SAMPLE
 806                 },
 807                 &Trace_notify,
 808                 false, NULL, NULL
 809         },
 810
 811 #ifdef LOCK_DEBUG
 812         {
 813                 {"trace_locks", PGC_SUSET, DEVELOPER_OPTIONS,
 814                         gettext_noop("No description available."),
 815                         NULL,
 816                         GUC_NOT_IN_SAMPLE
 817                 },
 818                 &Trace_locks,
 819                 false, NULL, NULL
 820         },
 821         {
 822                 {"trace_userlocks", PGC_SUSET, DEVELOPER_OPTIONS,
 823                         gettext_noop("No description available."),
 824                         NULL,
 825                         GUC_NOT_IN_SAMPLE
 826                 },
 827                 &Trace_userlocks,
 828                 false, NULL, NULL
 829         },
 830         {
 831                 {"trace_lwlocks", PGC_SUSET, DEVELOPER_OPTIONS,
 832                         gettext_noop("No description available."),
 833                         NULL,
 834                         GUC_NOT_IN_SAMPLE
 835                 },
 836                 &Trace_lwlocks,
 837                 false, NULL, NULL
 838         },
 839         {
 840                 {"debug_deadlocks", PGC_SUSET, DEVELOPER_OPTIONS,
 841                         gettext_noop("No description available."),
 842                         NULL,
 843                         GUC_NOT_IN_SAMPLE
 844                 },
 845                 &Debug_deadlocks,
 846                 false, NULL, NULL
 847         },
 848 #endif
 849
 850         {
 851                 {"log_lock_waits", PGC_SUSET, LOGGING_WHAT,
 852                         gettext_noop("Logs long lock waits."),
 853                         NULL
 854                 },
 855                 &log_lock_waits,
 856                 false, NULL, NULL
 857         },
 858
 859         {
 860                 {"log_hostname", PGC_SIGHUP, LOGGING_WHAT,
 861                         gettext_noop("Logs the host name in the connection logs."),
 862                         gettext_noop("By default, connection logs only show the IP address "
 863                                                  "of the connecting host. If you want them to show the host name you "
 864                           "can turn this on, but depending on your host name resolution "
 865                            "setup it might impose a non-negligible performance penalty.")
 866                 },
 867                 &log_hostname,
 868                 false, NULL, NULL
 869         },
 870         {
 871                 {"sql_inheritance", PGC_USERSET, COMPAT_OPTIONS_PREVIOUS,
 872                         gettext_noop("Causes subtables to be included by default in various commands."),
 873                         NULL
 874                 },
 875                 &SQL_inheritance,
 876                 true, NULL, NULL
 877         },
 878         {
 879                 {"password_encryption", PGC_USERSET, CONN_AUTH_SECURITY,
 880                         gettext_noop("Encrypt passwords."),
 881                         gettext_noop("When a password is specified in CREATE USER or "
 882                            "ALTER USER without writing either ENCRYPTED or UNENCRYPTED, "
 883                                                  "this parameter determines whether the password is to be encrypted.")
 884                 },
 885                 &Password_encryption,
 886                 true, NULL, NULL
 887         },
 888         {
 889                 {"transform_null_equals", PGC_USERSET, COMPAT_OPTIONS_CLIENT,
 890                         gettext_noop("Treats \"expr=NULL\" as \"expr IS NULL\"."),
 891                         gettext_noop("When turned on, expressions of the form expr = NULL "
 892                            "(or NULL = expr) are treated as expr IS NULL, that is, they "
 893                                 "return true if expr evaluates to the null value, and false "
 894                            "otherwise. The correct behavior of expr = NULL is to always "
 895                                                  "return null (unknown).")
 896                 },
 897                 &Transform_null_equals,
 898                 false, NULL, NULL
 899         },
 900         {
 901                 {"db_user_namespace", PGC_SIGHUP, CONN_AUTH_SECURITY,
 902                         gettext_noop("Enables per-database user names."),
 903                         NULL
 904                 },
 905                 &Db_user_namespace,
 906                 false, NULL, NULL
 907         },
 908         {
 909                 /* only here for backwards compatibility */
 910                 {"autocommit", PGC_USERSET, CLIENT_CONN_STATEMENT,
 911                         gettext_noop("This parameter doesn't do anything."),
 912                         gettext_noop("It's just here so that we won't choke on SET AUTOCOMMIT TO ON from 7.3-vintage clients."),
 913                         GUC_NO_SHOW_ALL | GUC_NOT_IN_SAMPLE
 914                 },
 915                 &phony_autocommit,
 916                 true, assign_phony_autocommit, NULL
 917         },
 918         {
 919                 {"default_transaction_read_only", PGC_USERSET, CLIENT_CONN_STATEMENT,
 920                         gettext_noop("Sets the default read-only status of new transactions."),
 921                         NULL
 922                 },
 923                 &DefaultXactReadOnly,
 924                 false, NULL, NULL
 925         },
 926         {
 927                 {"transaction_read_only", PGC_USERSET, CLIENT_CONN_STATEMENT,
 928                         gettext_noop("Sets the current transaction's read-only status."),
 929                         NULL,
 930                         GUC_NO_RESET_ALL | GUC_NOT_IN_SAMPLE | GUC_DISALLOW_IN_FILE
 931                 },
 932                 &XactReadOnly,
 933                 false, assign_transaction_read_only, NULL
 934         },
 935         {
 936                 {"add_missing_from", PGC_USERSET, COMPAT_OPTIONS_PREVIOUS,
 937                         gettext_noop("Automatically adds missing table references to FROM clauses."),
 938                         NULL
 939                 },
 940                 &add_missing_from,
 941                 false, NULL, NULL
 942         },
 943         {
 944                 {"check_function_bodies", PGC_USERSET, CLIENT_CONN_STATEMENT,
 945                         gettext_noop("Check function bodies during CREATE FUNCTION."),
 946                         NULL
 947                 },
 948                 &check_function_bodies,
 949                 true, NULL, NULL
 950         },
 951         {
 952                 {"array_nulls", PGC_USERSET, COMPAT_OPTIONS_PREVIOUS,
 953                         gettext_noop("Enable input of NULL elements in arrays."),
 954                         gettext_noop("When turned on, unquoted NULL in an array input "
 955                                                  "value means a null value; "
 956                                                  "otherwise it is taken literally.")
 957                 },
 958                 &Array_nulls,
 959                 true, NULL, NULL
 960         },
 961         {
 962                 {"default_with_oids", PGC_USERSET, COMPAT_OPTIONS_PREVIOUS,
 963                         gettext_noop("Create new tables with OIDs by default."),
 964                         NULL
 965                 },
 966                 &default_with_oids,
 967                 false, NULL, NULL
 968         },
 969         {
 970                 {"redirect_stderr", PGC_POSTMASTER, LOGGING_WHERE,
 971                         gettext_noop("Start a subprocess to capture stderr output into log files."),
 972                         NULL
 973                 },
 974                 &Redirect_stderr,
 975                 false, NULL, NULL
 976         },
 977         {
 978                 {"log_truncate_on_rotation", PGC_SIGHUP, LOGGING_WHERE,
 979                         gettext_noop("Truncate existing log files of same name during log rotation."),
 980                         NULL
 981                 },
 982                 &Log_truncate_on_rotation,
 983                 false, NULL, NULL
 984         },
 985
 986 #ifdef TRACE_SORT
 987         {
 988                 {"trace_sort", PGC_USERSET, DEVELOPER_OPTIONS,
 989                         gettext_noop("Emit information about resource usage in sorting."),
 990                         NULL,
 991                         GUC_NOT_IN_SAMPLE
 992                 },
 993                 &trace_sort,
 994                 false, NULL, NULL
 995         },
 996 #endif
 997
 998 #ifdef TRACE_SYNCSCAN
 999         /* this is undocumented because not exposed in a standard build */
1000         {
1001                 {"trace_syncscan", PGC_USERSET, DEVELOPER_OPTIONS,
1002                         gettext_noop("Generate debugging output for synchronized scanning."),
1003                         NULL,
1004                         GUC_NOT_IN_SAMPLE
1005                 },
1006                 &trace_syncscan,
1007                 false, NULL, NULL
1008         },
1009 #endif
1010
1011 #ifdef DEBUG_BOUNDED_SORT
1012         /* this is undocumented because not exposed in a standard build */
1013         {
1014                 {
1015                         "optimize_bounded_sort", PGC_USERSET, QUERY_TUNING_METHOD,
1016                         gettext_noop("Enable bounded sorting using heap sort."),
1017                         NULL,
1018                         GUC_NOT_IN_SAMPLE
1019                 },
1020                 &optimize_bounded_sort,
1021                 true, NULL, NULL
1022         },
1023 #endif
1024
1025 #ifdef WAL_DEBUG
1026         {
1027                 {"wal_debug", PGC_SUSET, DEVELOPER_OPTIONS,
1028                         gettext_noop("Emit WAL-related debugging output."),
1029                         NULL,
1030                         GUC_NOT_IN_SAMPLE
1031                 },
1032                 &XLOG_DEBUG,
1033                 false, NULL, NULL
1034         },
1035 #endif
1036
1037         {
1038                 {"integer_datetimes", PGC_INTERNAL, PRESET_OPTIONS,
1039                         gettext_noop("Datetimes are integer based."),
1040                         NULL,
1041                         GUC_REPORT | GUC_NOT_IN_SAMPLE | GUC_DISALLOW_IN_FILE
1042                 },
1043                 &integer_datetimes,
1044 #ifdef HAVE_INT64_TIMESTAMP
1045                 true, NULL, NULL
1046 #else
1047                 false, NULL, NULL
1048 #endif
1049         },
1050
1051         {
1052                 {"krb_caseins_users", PGC_POSTMASTER, CONN_AUTH_SECURITY,
1053                         gettext_noop("Sets whether Kerberos and GSSAPI user names should be treated as case-insensitive."),
1054                         NULL
1055                 },
1056                 &pg_krb_caseins_users,
1057                 false, NULL, NULL
1058         },
1059
1060         {
1061                 {"escape_string_warning", PGC_USERSET, COMPAT_OPTIONS_PREVIOUS,
1062                         gettext_noop("Warn about backslash escapes in ordinary string literals."),
1063                         NULL
1064                 },
1065                 &escape_string_warning,
1066                 true, NULL, NULL
1067         },
1068
1069         {
1070                 {"standard_conforming_strings", PGC_USERSET, COMPAT_OPTIONS_PREVIOUS,
1071                         gettext_noop("Causes '...' strings to treat backslashes literally."),
1072                         NULL,
1073                         GUC_REPORT
1074                 },
1075                 &standard_conforming_strings,
1076                 false, NULL, NULL
1077         },
1078
1079         {
1080                 {"allow_system_table_mods", PGC_POSTMASTER, DEVELOPER_OPTIONS,
1081                         gettext_noop("Allows modifications of the structure of system tables."),
1082                         NULL,
1083                         GUC_NOT_IN_SAMPLE
1084                 },
1085                 &allowSystemTableMods,
1086                 false, NULL, NULL
1087         },
1088
1089         {
1090                 {"ignore_system_indexes", PGC_BACKEND, DEVELOPER_OPTIONS,
1091                         gettext_noop("Disables reading from system indexes."),
1092                         gettext_noop("It does not prevent updating the indexes, so it is safe "
1093                                                  "to use.  The worst consequence is slowness."),
1094                         GUC_NOT_IN_SAMPLE
1095                 },
1096                 &IgnoreSystemIndexes,
1097                 false, NULL, NULL
1098         },
1099
1100         /* End-of-list marker */
1101         {
1102                 {NULL, 0, 0, NULL, NULL}, NULL, false, NULL, NULL
1103         }
1104 };
1105
1106
1107 static struct config_int ConfigureNamesInt[] =
1108 {
1109         {
1110                 {"archive_timeout", PGC_SIGHUP, WAL_SETTINGS,
1111                         gettext_noop("Forces a switch to the next xlog file if a "
1112                                                  "new file has not been started within N seconds."),
1113                         NULL,
1114                         GUC_UNIT_S
1115                 },
1116                 &XLogArchiveTimeout,
1117                 0, 0, INT_MAX, NULL, NULL
1118         },
1119         {
1120                 {"post_auth_delay", PGC_BACKEND, DEVELOPER_OPTIONS,
1121                         gettext_noop("Waits N seconds on connection startup after authentication."),
1122                         gettext_noop("This allows attaching a debugger to the process."),
1123                         GUC_NOT_IN_SAMPLE | GUC_UNIT_S
1124                 },
1125                 &PostAuthDelay,
1126                 0, 0, INT_MAX, NULL, NULL
1127         },
1128         {
1129                 {"default_statistics_target", PGC_USERSET, QUERY_TUNING_OTHER,
1130                         gettext_noop("Sets the default statistics target."),
1131                         gettext_noop("This applies to table columns that have not had a "
1132                                 "column-specific target set via ALTER TABLE SET STATISTICS.")
1133                 },
1134                 &default_statistics_target,
1135                 10, 1, 1000, NULL, NULL
1136         },
1137         {
1138                 {"from_collapse_limit", PGC_USERSET, QUERY_TUNING_OTHER,
1139                         gettext_noop("Sets the FROM-list size beyond which subqueries "
1140                                                  "are not collapsed."),
1141                         gettext_noop("The planner will merge subqueries into upper "
1142                                 "queries if the resulting FROM list would have no more than "
1143                                                  "this many items.")
1144                 },
1145                 &from_collapse_limit,
1146                 8, 1, INT_MAX, NULL, NULL
1147         },
1148         {
1149                 {"join_collapse_limit", PGC_USERSET, QUERY_TUNING_OTHER,
1150                         gettext_noop("Sets the FROM-list size beyond which JOIN "
1151                                                  "constructs are not flattened."),
1152                         gettext_noop("The planner will flatten explicit JOIN "
1153                                                  "constructs into lists of FROM items whenever a "
1154                                                  "list of no more than this many items would result.")
1155                 },
1156                 &join_collapse_limit,
1157                 8, 1, INT_MAX, NULL, NULL
1158         },
1159         {
1160                 {"geqo_threshold", PGC_USERSET, QUERY_TUNING_GEQO,
1161                         gettext_noop("Sets the threshold of FROM items beyond which GEQO is used."),
1162                         NULL
1163                 },
1164                 &geqo_threshold,
1165                 12, 2, INT_MAX, NULL, NULL
1166         },
1167         {
1168                 {"geqo_effort", PGC_USERSET, QUERY_TUNING_GEQO,
1169                         gettext_noop("GEQO: effort is used to set the default for other GEQO parameters."),
1170                         NULL
1171                 },
1172                 &Geqo_effort,
1173                 DEFAULT_GEQO_EFFORT, MIN_GEQO_EFFORT, MAX_GEQO_EFFORT, NULL, NULL
1174         },
1175         {
1176                 {"geqo_pool_size", PGC_USERSET, QUERY_TUNING_GEQO,
1177                         gettext_noop("GEQO: number of individuals in the population."),
1178                         gettext_noop("Zero selects a suitable default value.")
1179                 },
1180                 &Geqo_pool_size,
1181                 0, 0, INT_MAX, NULL, NULL
1182         },
1183         {
1184                 {"geqo_generations", PGC_USERSET, QUERY_TUNING_GEQO,
1185                         gettext_noop("GEQO: number of iterations of the algorithm."),
1186                         gettext_noop("Zero selects a suitable default value.")
1187                 },
1188                 &Geqo_generations,
1189                 0, 0, INT_MAX, NULL, NULL
1190         },
1191
1192         {
1193                 {"deadlock_timeout", PGC_SIGHUP, LOCK_MANAGEMENT,
1194                         gettext_noop("Sets the time to wait on a lock before checking for deadlock."),
1195                         NULL,
1196                         GUC_UNIT_MS
1197                 },
1198                 &DeadlockTimeout,
1199                 1000, 1, INT_MAX/1000, NULL, NULL
1200         },
1201
1202         /*
1203          * Note: There is some postprocessing done in PostmasterMain() to make
1204          * sure the buffers are at least twice the number of backends, so the
1205          * constraints here are partially unused. Similarly, the superuser
1206          * reserved number is checked to ensure it is less than the max backends
1207          * number.
1208          *
1209          * MaxBackends is limited to INT_MAX/4 because some places compute
1210          * 4*MaxBackends without any overflow check.  This check is made on
1211          * assign_maxconnections, since MaxBackends is computed as MaxConnections +
1212          * autovacuum_max_workers.
1213          *
1214          * Likewise we have to limit NBuffers to INT_MAX/2.
1215          */
1216         {
1217                 {"max_connections", PGC_POSTMASTER, CONN_AUTH_SETTINGS,
1218                         gettext_noop("Sets the maximum number of concurrent connections."),
1219                         NULL
1220                 },
1221                 &MaxConnections,
1222                 100, 1, INT_MAX / 4, assign_maxconnections, NULL
1223         },
1224
1225         {
1226                 {"superuser_reserved_connections", PGC_POSTMASTER, CONN_AUTH_SETTINGS,
1227                         gettext_noop("Sets the number of connection slots reserved for superusers."),
1228                         NULL
1229                 },
1230                 &ReservedBackends,
1231                 3, 0, INT_MAX / 4, NULL, NULL
1232         },
1233
1234         {
1235                 {"shared_buffers", PGC_POSTMASTER, RESOURCES_MEM,
1236                         gettext_noop("Sets the number of shared memory buffers used by the server."),
1237                         NULL,
1238                         GUC_UNIT_BLOCKS
1239                 },
1240                 &NBuffers,
1241                 1024, 16, INT_MAX / 2, NULL, NULL
1242         },
1243
1244         {
1245                 {"temp_buffers", PGC_USERSET, RESOURCES_MEM,
1246                         gettext_noop("Sets the maximum number of temporary buffers used by each session."),
1247                         NULL,
1248                         GUC_UNIT_BLOCKS
1249                 },
1250                 &num_temp_buffers,
1251                 1024, 100, INT_MAX / 2, NULL, show_num_temp_buffers
1252         },
1253
1254         {
1255                 {"port", PGC_POSTMASTER, CONN_AUTH_SETTINGS,
1256                         gettext_noop("Sets the TCP port the server listens on."),
1257                         NULL
1258                 },
1259                 &PostPortNumber,
1260                 DEF_PGPORT, 1, 65535, NULL, NULL
1261         },
1262
1263         {
1264                 {"unix_socket_permissions", PGC_POSTMASTER, CONN_AUTH_SETTINGS,
1265                         gettext_noop("Sets the access permissions of the Unix-domain socket."),
1266                         gettext_noop("Unix-domain sockets use the usual Unix file system "
1267                                                  "permission set. The parameter value is expected to be an numeric mode "
1268                                                  "specification in the form accepted by the chmod and umask system "
1269                                                  "calls. (To use the customary octal format the number must start with "
1270                                                  "a 0 (zero).)")
1271                 },
1272                 &Unix_socket_permissions,
1273                 0777, 0000, 0777, NULL, NULL
1274         },
1275
1276         {
1277                 {"work_mem", PGC_USERSET, RESOURCES_MEM,
1278                         gettext_noop("Sets the maximum memory to be used for query workspaces."),
1279                         gettext_noop("This much memory can be used by each internal "
1280                                                  "sort operation and hash table before switching to "
1281                                                  "temporary disk files."),
1282                         GUC_UNIT_KB
1283                 },
1284                 &work_mem,
1285                 1024, 8 * BLCKSZ / 1024, MAX_KILOBYTES, NULL, NULL
1286         },
1287
1288         {
1289                 {"maintenance_work_mem", PGC_USERSET, RESOURCES_MEM,
1290                         gettext_noop("Sets the maximum memory to be used for maintenance operations."),
1291                         gettext_noop("This includes operations such as VACUUM and CREATE INDEX."),
1292                         GUC_UNIT_KB
1293                 },
1294                 &maintenance_work_mem,
1295                 16384, 1024, MAX_KILOBYTES, NULL, NULL
1296         },
1297
1298         {
1299                 {"max_stack_depth", PGC_SUSET, RESOURCES_MEM,
1300                         gettext_noop("Sets the maximum stack depth, in kilobytes."),
1301                         NULL,
1302                         GUC_UNIT_KB
1303                 },
1304                 &max_stack_depth,
1305                 100, 100, MAX_KILOBYTES, assign_max_stack_depth, NULL
1306         },
1307
1308         {
1309                 {"vacuum_cost_page_hit", PGC_USERSET, RESOURCES,
1310                         gettext_noop("Vacuum cost for a page found in the buffer cache."),
1311                         NULL
1312                 },
1313                 &VacuumCostPageHit,
1314                 1, 0, 10000, NULL, NULL
1315         },
1316
1317         {
1318                 {"vacuum_cost_page_miss", PGC_USERSET, RESOURCES,
1319                         gettext_noop("Vacuum cost for a page not found in the buffer cache."),
1320                         NULL
1321                 },
1322                 &VacuumCostPageMiss,
1323                 10, 0, 10000, NULL, NULL
1324         },
1325
1326         {
1327                 {"vacuum_cost_page_dirty", PGC_USERSET, RESOURCES,
1328                         gettext_noop("Vacuum cost for a page dirtied by vacuum."),
1329                         NULL
1330                 },
1331                 &VacuumCostPageDirty,
1332                 20, 0, 10000, NULL, NULL
1333         },
1334
1335         {
1336                 {"vacuum_cost_limit", PGC_USERSET, RESOURCES,
1337                         gettext_noop("Vacuum cost amount available before napping."),
1338                         NULL
1339                 },
1340                 &VacuumCostLimit,
1341                 200, 1, 10000, NULL, NULL
1342         },
1343
1344         {
1345                 {"vacuum_cost_delay", PGC_USERSET, RESOURCES,
1346                         gettext_noop("Vacuum cost delay in milliseconds."),
1347                         NULL,
1348                         GUC_UNIT_MS
1349                 },
1350                 &VacuumCostDelay,
1351                 0, 0, 1000, NULL, NULL
1352         },
1353
1354         {
1355                 {"autovacuum_vacuum_cost_delay", PGC_SIGHUP, AUTOVACUUM,
1356                         gettext_noop("Vacuum cost delay in milliseconds, for autovacuum."),
1357                         NULL,
1358                         GUC_UNIT_MS
1359                 },
1360                 &autovacuum_vac_cost_delay,
1361                 20, -1, 1000, NULL, NULL
1362         },
1363
1364         {
1365                 {"autovacuum_vacuum_cost_limit", PGC_SIGHUP, AUTOVACUUM,
1366                         gettext_noop("Vacuum cost amount available before napping, for autovacuum."),
1367                         NULL
1368                 },
1369                 &autovacuum_vac_cost_limit,
1370                 -1, -1, 10000, NULL, NULL
1371         },
1372
1373         {
1374                 {"max_files_per_process", PGC_POSTMASTER, RESOURCES_KERNEL,
1375                         gettext_noop("Sets the maximum number of simultaneously open files for each server process."),
1376                         NULL
1377                 },
1378                 &max_files_per_process,
1379                 1000, 25, INT_MAX, NULL, NULL
1380         },
1381
1382         {
1383                 {"max_prepared_transactions", PGC_POSTMASTER, RESOURCES,
1384                         gettext_noop("Sets the maximum number of simultaneously prepared transactions."),
1385                         NULL
1386                 },
1387                 &max_prepared_xacts,
1388                 5, 0, INT_MAX, NULL, NULL
1389         },
1390
1391 #ifdef LOCK_DEBUG
1392         {
1393                 {"trace_lock_oidmin", PGC_SUSET, DEVELOPER_OPTIONS,
1394                         gettext_noop("No description available."),
1395                         NULL,
1396                         GUC_NOT_IN_SAMPLE
1397                 },
1398                 &Trace_lock_oidmin,
1399                 FirstNormalObjectId, 0, INT_MAX, NULL, NULL
1400         },
1401         {
1402                 {"trace_lock_table", PGC_SUSET, DEVELOPER_OPTIONS,
1403                         gettext_noop("No description available."),
1404                         NULL,
1405                         GUC_NOT_IN_SAMPLE
1406                 },
1407                 &Trace_lock_table,
1408                 0, 0, INT_MAX, NULL, NULL
1409         },
1410 #endif
1411
1412         {
1413                 {"statement_timeout", PGC_USERSET, CLIENT_CONN_STATEMENT,
1414                         gettext_noop("Sets the maximum allowed duration of any statement."),
1415                         gettext_noop("A value of 0 turns off the timeout."),
1416                         GUC_UNIT_MS
1417                 },
1418                 &StatementTimeout,
1419                 0, 0, INT_MAX, NULL, NULL
1420         },
1421
1422         {
1423                 {"vacuum_freeze_min_age", PGC_USERSET, CLIENT_CONN_STATEMENT,
1424                         gettext_noop("Minimum age at which VACUUM should freeze a table row."),
1425                         NULL
1426                 },
1427                 &vacuum_freeze_min_age,
1428                 100000000, 0, 1000000000, NULL, NULL
1429         },
1430
1431         {
1432                 {"max_fsm_relations", PGC_POSTMASTER, RESOURCES_FSM,
1433                         gettext_noop("Sets the maximum number of tables and indexes for which free space is tracked."),
1434                         NULL
1435                 },
1436                 &MaxFSMRelations,
1437                 1000, 100, INT_MAX, NULL, NULL
1438         },
1439         {
1440                 {"max_fsm_pages", PGC_POSTMASTER, RESOURCES_FSM,
1441                         gettext_noop("Sets the maximum number of disk pages for which free space is tracked."),
1442                         NULL
1443                 },
1444                 &MaxFSMPages,
1445                 20000, 1000, INT_MAX, NULL, NULL
1446         },
1447
1448         {
1449                 {"max_locks_per_transaction", PGC_POSTMASTER, LOCK_MANAGEMENT,
1450                         gettext_noop("Sets the maximum number of locks per transaction."),
1451                         gettext_noop("The shared lock table is sized on the assumption that "
1452                           "at most max_locks_per_transaction * max_connections distinct "
1453                                                  "objects will need to be locked at any one time.")
1454                 },
1455                 &max_locks_per_xact,
1456                 64, 10, INT_MAX, NULL, NULL
1457         },
1458
1459         {
1460                 {"authentication_timeout", PGC_SIGHUP, CONN_AUTH_SECURITY,
1461                         gettext_noop("Sets the maximum allowed time to complete client authentication."),
1462                         NULL,
1463                         GUC_UNIT_S
1464                 },
1465                 &AuthenticationTimeout,
1466                 60, 1, 600, NULL, NULL
1467         },
1468
1469         {
1470                 /* Not for general use */
1471                 {"pre_auth_delay", PGC_SIGHUP, DEVELOPER_OPTIONS,
1472                         gettext_noop("Waits N seconds on connection startup before authentication."),
1473                         gettext_noop("This allows attaching a debugger to the process."),
1474                         GUC_NOT_IN_SAMPLE | GUC_UNIT_S
1475                 },
1476                 &PreAuthDelay,
1477                 0, 0, 60, NULL, NULL
1478         },
1479
1480         {
1481                 {"checkpoint_segments", PGC_SIGHUP, WAL_CHECKPOINTS,
1482                         gettext_noop("Sets the maximum distance in log segments between automatic WAL checkpoints."),
1483                         NULL
1484                 },
1485                 &CheckPointSegments,
1486                 3, 1, INT_MAX, NULL, NULL
1487         },
1488
1489         {
1490                 {"checkpoint_timeout", PGC_SIGHUP, WAL_CHECKPOINTS,
1491                         gettext_noop("Sets the maximum time between automatic WAL checkpoints."),
1492                         NULL,
1493                         GUC_UNIT_S
1494                 },
1495                 &CheckPointTimeout,
1496                 300, 30, 3600, NULL, NULL
1497         },
1498
1499         {
1500                 {"checkpoint_warning", PGC_SIGHUP, WAL_CHECKPOINTS,
1501                         gettext_noop("Enables warnings if checkpoint segments are filled more "
1502                                                  "frequently than this."),
1503                         gettext_noop("Write a message to the server log if checkpoints "
1504                         "caused by the filling of checkpoint segment files happens more "
1505                                                  "frequently than this number of seconds. Zero turns off the warning."),
1506                         GUC_UNIT_S
1507                 },
1508                 &CheckPointWarning,
1509                 30, 0, INT_MAX, NULL, NULL
1510         },
1511
1512         {
1513                 {"wal_buffers", PGC_POSTMASTER, WAL_SETTINGS,
1514                         gettext_noop("Sets the number of disk-page buffers in shared memory for WAL."),
1515                         NULL,
1516                         GUC_UNIT_XBLOCKS
1517                 },
1518                 &XLOGbuffers,
1519                 8, 4, INT_MAX, NULL, NULL
1520         },
1521
1522         {
1523                 {"wal_writer_delay", PGC_SIGHUP, WAL_SETTINGS,
1524                         gettext_noop("WAL writer sleep time between WAL flushes."),
1525                         NULL,
1526                         GUC_UNIT_MS
1527                 },
1528                 &WalWriterDelay,
1529                 200, 1, 10000, NULL, NULL
1530         },
1531
1532         {
1533                 {"commit_delay", PGC_USERSET, WAL_SETTINGS,
1534                         gettext_noop("Sets the delay in microseconds between transaction commit and "
1535                                                  "flushing WAL to disk."),
1536                         NULL
1537                 },
1538                 &CommitDelay,
1539                 0, 0, 100000, NULL, NULL
1540         },
1541
1542         {
1543                 {"commit_siblings", PGC_USERSET, WAL_SETTINGS,
1544                         gettext_noop("Sets the minimum concurrent open transactions before performing "
1545                                                  "commit_delay."),
1546                         NULL
1547                 },
1548                 &CommitSiblings,
1549                 5, 1, 1000, NULL, NULL
1550         },
1551
1552         {
1553                 {"extra_float_digits", PGC_USERSET, CLIENT_CONN_LOCALE,
1554                         gettext_noop("Sets the number of digits displayed for floating-point values."),
1555                         gettext_noop("This affects real, double precision, and geometric data types. "
1556                          "The parameter value is added to the standard number of digits "
1557                                                  "(FLT_DIG or DBL_DIG as appropriate).")
1558                 },
1559                 &extra_float_digits,
1560                 0, -15, 2, NULL, NULL
1561         },
1562
1563         {
1564                 {"log_min_duration_statement", PGC_SUSET, LOGGING_WHEN,
1565                         gettext_noop("Sets the minimum execution time above which statements will "
1566                                                  "be logged."),
1567                         gettext_noop("Zero prints all queries. The default is -1 (turning this feature off)."),
1568                         GUC_UNIT_MS
1569                 },
1570                 &log_min_duration_statement,
1571                 -1, -1, INT_MAX / 1000, NULL, NULL
1572         },
1573
1574         {
1575                 {"log_autovacuum", PGC_BACKEND, LOGGING_WHAT,
1576                         gettext_noop("Sets the minimum execution time above which autovacuum actions "
1577                                                  "will be logged."),
1578                         gettext_noop("Zero prints all actions.  The default is -1 (turning this feature off)."),
1579                         GUC_UNIT_MS
1580                 },
1581                 &Log_autovacuum,
1582                 -1, -1, INT_MAX / 1000, NULL, NULL
1583         },
1584
1585         {
1586                 {"bgwriter_delay", PGC_SIGHUP, RESOURCES,
1587                         gettext_noop("Background writer sleep time between rounds."),
1588                         NULL,
1589                         GUC_UNIT_MS
1590                 },
1591                 &BgWriterDelay,
1592                 200, 10, 10000, NULL, NULL
1593         },
1594
1595         {
1596                 {"bgwriter_lru_maxpages", PGC_SIGHUP, RESOURCES,
1597                         gettext_noop("Background writer maximum number of LRU pages to flush per round."),
1598                         NULL
1599                 },
1600                 &bgwriter_lru_maxpages,
1601                 5, 0, 1000, NULL, NULL
1602         },
1603
1604         {
1605                 {"log_rotation_age", PGC_SIGHUP, LOGGING_WHERE,
1606                         gettext_noop("Automatic log file rotation will occur after N minutes."),
1607                         NULL,
1608                         GUC_UNIT_MIN
1609                 },
1610                 &Log_RotationAge,
1611                 HOURS_PER_DAY * MINS_PER_HOUR, 0, INT_MAX / MINS_PER_HOUR, NULL, NULL
1612         },
1613
1614         {
1615                 {"log_rotation_size", PGC_SIGHUP, LOGGING_WHERE,
1616                         gettext_noop("Automatic log file rotation will occur after N kilobytes."),
1617                         NULL,
1618                         GUC_UNIT_KB
1619                 },
1620                 &Log_RotationSize,
1621                 10 * 1024, 0, INT_MAX / 1024, NULL, NULL
1622         },
1623
1624         {
1625                 {"max_function_args", PGC_INTERNAL, PRESET_OPTIONS,
1626                         gettext_noop("Shows the maximum number of function arguments."),
1627                         NULL,
1628                         GUC_NOT_IN_SAMPLE | GUC_DISALLOW_IN_FILE
1629                 },
1630                 &max_function_args,
1631                 FUNC_MAX_ARGS, FUNC_MAX_ARGS, FUNC_MAX_ARGS, NULL, NULL
1632         },
1633
1634         {
1635                 {"max_index_keys", PGC_INTERNAL, PRESET_OPTIONS,
1636                         gettext_noop("Shows the maximum number of index keys."),
1637                         NULL,
1638                         GUC_NOT_IN_SAMPLE | GUC_DISALLOW_IN_FILE
1639                 },
1640                 &max_index_keys,
1641                 INDEX_MAX_KEYS, INDEX_MAX_KEYS, INDEX_MAX_KEYS, NULL, NULL
1642         },
1643
1644         {
1645                 {"max_identifier_length", PGC_INTERNAL, PRESET_OPTIONS,
1646                         gettext_noop("Shows the maximum identifier length."),
1647                         NULL,
1648                         GUC_NOT_IN_SAMPLE | GUC_DISALLOW_IN_FILE
1649                 },
1650                 &max_identifier_length,
1651                 NAMEDATALEN - 1, NAMEDATALEN - 1, NAMEDATALEN - 1, NULL, NULL
1652         },
1653
1654         {
1655                 {"block_size", PGC_INTERNAL, PRESET_OPTIONS,
1656                         gettext_noop("Shows the size of a disk block."),
1657                         NULL,
1658                         GUC_NOT_IN_SAMPLE | GUC_DISALLOW_IN_FILE
1659                 },
1660                 &block_size,
1661                 BLCKSZ, BLCKSZ, BLCKSZ, NULL, NULL
1662         },
1663
1664         {
1665                 {"autovacuum_naptime", PGC_SIGHUP, AUTOVACUUM,
1666                         gettext_noop("Time to sleep between autovacuum runs."),
1667                         NULL,
1668                         GUC_UNIT_S
1669                 },
1670                 &autovacuum_naptime,
1671                 60, 1, INT_MAX / 1000, NULL, NULL
1672         },
1673         {
1674                 {"autovacuum_vacuum_threshold", PGC_SIGHUP, AUTOVACUUM,
1675                         gettext_noop("Minimum number of tuple updates or deletes prior to vacuum."),
1676                         NULL
1677                 },
1678                 &autovacuum_vac_thresh,
1679                 50, 0, INT_MAX, NULL, NULL
1680         },
1681         {
1682                 {"autovacuum_analyze_threshold", PGC_SIGHUP, AUTOVACUUM,
1683                         gettext_noop("Minimum number of tuple inserts, updates or deletes prior to analyze."),
1684                         NULL
1685                 },
1686                 &autovacuum_anl_thresh,
1687                 50, 0, INT_MAX, NULL, NULL
1688         },
1689         {
1690                 /* see varsup.c for why this is PGC_POSTMASTER not PGC_SIGHUP */
1691                 {"autovacuum_freeze_max_age", PGC_POSTMASTER, AUTOVACUUM,
1692                         gettext_noop("Age at which to autovacuum a table to prevent transaction ID wraparound."),
1693                         NULL
1694                 },
1695                 &autovacuum_freeze_max_age,
1696                 200000000, 100000000, 2000000000, NULL, NULL
1697         },
1698         {
1699                 /* see max_connections */
1700                 {"autovacuum_max_workers", PGC_POSTMASTER, AUTOVACUUM,
1701                         gettext_noop("Sets the maximum number of simultaneously running autovacuum worker processes."),
1702                         NULL
1703                 },
1704                 &autovacuum_max_workers,
1705                 3, 1, INT_MAX / 4, assign_autovacuum_max_workers, NULL
1706         },
1707
1708         {
1709                 {"tcp_keepalives_idle", PGC_USERSET, CLIENT_CONN_OTHER,
1710                         gettext_noop("Time between issuing TCP keepalives."),
1711                         gettext_noop("A value of 0 uses the system default."),
1712                         GUC_UNIT_S
1713                 },
1714                 &tcp_keepalives_idle,
1715                 0, 0, INT_MAX, assign_tcp_keepalives_idle, show_tcp_keepalives_idle
1716         },
1717
1718         {
1719                 {"tcp_keepalives_interval", PGC_USERSET, CLIENT_CONN_OTHER,
1720                         gettext_noop("Time between TCP keepalive retransmits."),
1721                         gettext_noop("A value of 0 uses the system default."),
1722                         GUC_UNIT_S
1723                 },
1724                 &tcp_keepalives_interval,
1725                 0, 0, INT_MAX, assign_tcp_keepalives_interval, show_tcp_keepalives_interval
1726         },
1727
1728         {
1729                 {"tcp_keepalives_count", PGC_USERSET, CLIENT_CONN_OTHER,
1730                         gettext_noop("Maximum number of TCP keepalive retransmits."),
1731                         gettext_noop("This controls the number of consecutive keepalive retransmits that can be "
1732                                                  "lost before a connection is considered dead. A value of 0 uses the "
1733                                                  "system default."),
1734                 },
1735                 &tcp_keepalives_count,
1736                 0, 0, INT_MAX, assign_tcp_keepalives_count, show_tcp_keepalives_count
1737         },
1738
1739         {
1740                 {"gin_fuzzy_search_limit", PGC_USERSET, CLIENT_CONN_OTHER,
1741                         gettext_noop("Sets the maximum allowed result for exact search by GIN."),
1742                         NULL,
1743                         0
1744                 },
1745                 &GinFuzzySearchLimit,
1746                 0, 0, INT_MAX, NULL, NULL
1747         },
1748
1749         {
1750                 {"effective_cache_size", PGC_USERSET, QUERY_TUNING_COST,
1751                         gettext_noop("Sets the planner's assumption about the size of the disk cache."),
1752                         gettext_noop("That is, the portion of the kernel's disk cache that "
1753                                                  "will be used for PostgreSQL data files. This is measured in disk "
1754                                                  "pages, which are normally 8 kB each."),
1755                         GUC_UNIT_BLOCKS,
1756                 },
1757                 &effective_cache_size,
1758                 DEFAULT_EFFECTIVE_CACHE_SIZE, 1, INT_MAX, NULL, NULL
1759         },
1760
1761         {
1762                 /* Can't be set in postgresql.conf */
1763                 {"server_version_num", PGC_INTERNAL, PRESET_OPTIONS,
1764                         gettext_noop("Shows the server version as an integer."),
1765                         NULL,
1766                         GUC_NOT_IN_SAMPLE | GUC_DISALLOW_IN_FILE
1767                 },
1768                 &server_version_num,
1769                 PG_VERSION_NUM, PG_VERSION_NUM, PG_VERSION_NUM, NULL, NULL
1770         },
1771
1772         {
1773                 {"log_temp_files", PGC_USERSET, LOGGING_WHAT,
1774                         gettext_noop("Log the use of temporary files larger than this number of kilobytes."),
1775                         gettext_noop("Zero logs all files. The default is -1 (turning this feature off)."),
1776                         GUC_UNIT_KB
1777                 },
1778                 &log_temp_files,
1779                 -1, -1, INT_MAX, NULL, NULL
1780         },
1781
1782         /* End-of-list marker */
1783         {
1784                 {NULL, 0, 0, NULL, NULL}, NULL, 0, 0, 0, NULL, NULL
1785         }
1786 };
1787
1788
1789 static struct config_real ConfigureNamesReal[] =
1790 {
1791         {
1792                 {"seq_page_cost", PGC_USERSET, QUERY_TUNING_COST,
1793                         gettext_noop("Sets the planner's estimate of the cost of a "
1794                                                  "sequentially fetched disk page."),
1795                         NULL
1796                 },
1797                 &seq_page_cost,
1798                 DEFAULT_SEQ_PAGE_COST, 0, DBL_MAX, NULL, NULL
1799         },
1800         {
1801                 {"random_page_cost", PGC_USERSET, QUERY_TUNING_COST,
1802                         gettext_noop("Sets the planner's estimate of the cost of a "
1803                                                  "nonsequentially fetched disk page."),
1804                         NULL
1805                 },
1806                 &random_page_cost,
1807                 DEFAULT_RANDOM_PAGE_COST, 0, DBL_MAX, NULL, NULL
1808         },
1809         {
1810                 {"cpu_tuple_cost", PGC_USERSET, QUERY_TUNING_COST,
1811                         gettext_noop("Sets the planner's estimate of the cost of "
1812                                                  "processing each tuple (row)."),
1813                         NULL
1814                 },
1815                 &cpu_tuple_cost,
1816                 DEFAULT_CPU_TUPLE_COST, 0, DBL_MAX, NULL, NULL
1817         },
1818         {
1819                 {"cpu_index_tuple_cost", PGC_USERSET, QUERY_TUNING_COST,
1820                         gettext_noop("Sets the planner's estimate of the cost of "
1821                                                  "processing each index entry during an index scan."),
1822                         NULL
1823                 },
1824                 &cpu_index_tuple_cost,
1825                 DEFAULT_CPU_INDEX_TUPLE_COST, 0, DBL_MAX, NULL, NULL
1826         },
1827         {
1828                 {"cpu_operator_cost", PGC_USERSET, QUERY_TUNING_COST,
1829                         gettext_noop("Sets the planner's estimate of the cost of "
1830                                                  "processing each operator or function call."),
1831                         NULL
1832                 },
1833                 &cpu_operator_cost,
1834                 DEFAULT_CPU_OPERATOR_COST, 0, DBL_MAX, NULL, NULL
1835         },
1836
1837         {
1838                 {"geqo_selection_bias", PGC_USERSET, QUERY_TUNING_GEQO,
1839                         gettext_noop("GEQO: selective pressure within the population."),
1840                         NULL
1841                 },
1842                 &Geqo_selection_bias,
1843                 DEFAULT_GEQO_SELECTION_BIAS, MIN_GEQO_SELECTION_BIAS,
1844                 MAX_GEQO_SELECTION_BIAS, NULL, NULL
1845         },
1846
1847         {
1848                 {"bgwriter_lru_percent", PGC_SIGHUP, RESOURCES,
1849                         gettext_noop("Background writer percentage of LRU buffers to flush per round."),
1850                         NULL
1851                 },
1852                 &bgwriter_lru_percent,
1853                 1.0, 0.0, 100.0, NULL, NULL
1854         },
1855
1856         {
1857                 {"seed", PGC_USERSET, UNGROUPED,
1858                         gettext_noop("Sets the seed for random-number generation."),
1859                         NULL,
1860                         GUC_NO_SHOW_ALL | GUC_NO_RESET_ALL | GUC_NOT_IN_SAMPLE | GUC_DISALLOW_IN_FILE
1861                 },
1862                 &phony_random_seed,
1863                 0.5, 0.0, 1.0, assign_random_seed, show_random_seed
1864         },
1865
1866         {
1867                 {"autovacuum_vacuum_scale_factor", PGC_SIGHUP, AUTOVACUUM,
1868                         gettext_noop("Number of tuple updates or deletes prior to vacuum as a fraction of reltuples."),
1869                         NULL
1870                 },
1871                 &autovacuum_vac_scale,
1872                 0.2, 0.0, 100.0, NULL, NULL
1873         },
1874         {
1875                 {"autovacuum_analyze_scale_factor", PGC_SIGHUP, AUTOVACUUM,
1876                         gettext_noop("Number of tuple inserts, updates or deletes prior to analyze as a fraction of reltuples."),
1877                         NULL
1878                 },
1879                 &autovacuum_anl_scale,
1880                 0.1, 0.0, 100.0, NULL, NULL
1881         },
1882
1883         {
1884                 {"checkpoint_completion_target", PGC_SIGHUP, WAL_CHECKPOINTS,
1885                         gettext_noop("Time spent flushing dirty buffers during checkpoint, as fraction of checkpoint interval."),
1886                         NULL
1887                 },
1888                 &CheckPointCompletionTarget,
1889                 0.5, 0.0, 1.0, NULL, NULL
1890         },
1891
1892         /* End-of-list marker */
1893         {
1894                 {NULL, 0, 0, NULL, NULL}, NULL, 0.0, 0.0, 0.0, NULL, NULL
1895         }
1896 };
1897
1898
1899 static struct config_string ConfigureNamesString[] =
1900 {
1901         {
1902                 {"archive_command", PGC_SIGHUP, WAL_SETTINGS,
1903                         gettext_noop("Sets the shell command that will be called to archive a WAL file."),
1904                         NULL
1905                 },
1906                 &XLogArchiveCommand,
1907                 "", NULL, NULL
1908         },
1909
1910         {
1911                 {"backslash_quote", PGC_USERSET, COMPAT_OPTIONS_PREVIOUS,
1912                         gettext_noop("Sets whether \"\\'\" is allowed in string literals."),
1913                         gettext_noop("Valid values are ON, OFF, and SAFE_ENCODING.")
1914                 },
1915                 &backslash_quote_string,
1916                 "safe_encoding", assign_backslash_quote, NULL
1917         },
1918
1919         {
1920                 {"client_encoding", PGC_USERSET, CLIENT_CONN_LOCALE,
1921                         gettext_noop("Sets the client's character set encoding."),
1922                         NULL,
1923                         GUC_IS_NAME | GUC_REPORT
1924                 },
1925                 &client_encoding_string,
1926                 "SQL_ASCII", assign_client_encoding, NULL
1927         },
1928
1929         {
1930                 {"client_min_messages", PGC_USERSET, LOGGING_WHEN,
1931                         gettext_noop("Sets the message levels that are sent to the client."),
1932                         gettext_noop("Valid values are DEBUG5, DEBUG4, DEBUG3, DEBUG2, "
1933                                                  "DEBUG1, LOG, NOTICE, WARNING, and ERROR. Each level includes all the "
1934                                                  "levels that follow it. The later the level, the fewer messages are "
1935                                                  "sent.")
1936                 },
1937                 &client_min_messages_str,
1938                 "notice", assign_client_min_messages, NULL
1939         },
1940
1941         {
1942                 {"log_min_messages", PGC_SUSET, LOGGING_WHEN,
1943                         gettext_noop("Sets the message levels that are logged."),
1944                         gettext_noop("Valid values are DEBUG5, DEBUG4, DEBUG3, DEBUG2, DEBUG1, "
1945                         "INFO, NOTICE, WARNING, ERROR, LOG, FATAL, and PANIC. Each level "
1946                                                  "includes all the levels that follow it.")
1947                 },
1948                 &log_min_messages_str,
1949                 "notice", assign_log_min_messages, NULL
1950         },
1951
1952         {
1953                 {"log_error_verbosity", PGC_SUSET, LOGGING_WHEN,
1954                         gettext_noop("Sets the verbosity of logged messages."),
1955                         gettext_noop("Valid values are \"terse\", \"default\", and \"verbose\".")
1956                 },
1957                 &log_error_verbosity_str,
1958                 "default", assign_log_error_verbosity, NULL
1959         },
1960         {
1961                 {"log_statement", PGC_SUSET, LOGGING_WHAT,
1962                         gettext_noop("Sets the type of statements logged."),
1963                         gettext_noop("Valid values are \"none\", \"ddl\", \"mod\", and \"all\".")
1964                 },
1965                 &log_statement_str,
1966                 "none", assign_log_statement, NULL
1967         },
1968
1969         {
1970                 {"log_min_error_statement", PGC_SUSET, LOGGING_WHEN,
1971                         gettext_noop("Causes all statements generating error at or above this level to be logged."),
1972                         gettext_noop("All SQL statements that cause an error of the "
1973                                                  "specified level or a higher level are logged.")
1974                 },
1975                 &log_min_error_statement_str,
1976                 "error", assign_min_error_statement, NULL
1977         },
1978
1979         {
1980                 {"log_line_prefix", PGC_SIGHUP, LOGGING_WHAT,
1981                         gettext_noop("Controls information prefixed to each log line."),
1982                         gettext_noop("If blank, no prefix is used.")
1983                 },
1984                 &Log_line_prefix,
1985                 "", NULL, NULL
1986         },
1987
1988         {
1989                 {"log_timezone", PGC_SIGHUP, LOGGING_WHAT,
1990                         gettext_noop("Sets the time zone to use in log messages."),
1991                         NULL
1992                 },
1993                 &log_timezone_string,
1994                 "UNKNOWN", assign_log_timezone, show_log_timezone
1995         },
1996
1997         {
1998                 {"DateStyle", PGC_USERSET, CLIENT_CONN_LOCALE,
1999                         gettext_noop("Sets the display format for date and time values."),
2000                         gettext_noop("Also controls interpretation of ambiguous "
2001                                                  "date inputs."),
2002                         GUC_LIST_INPUT | GUC_REPORT
2003                 },
2004                 &datestyle_string,
2005                 "ISO, MDY", assign_datestyle, NULL
2006         },
2007
2008         {
2009                 {"default_tablespace", PGC_USERSET, CLIENT_CONN_STATEMENT,
2010                         gettext_noop("Sets the default tablespace to create tables and indexes in."),
2011                         gettext_noop("An empty string selects the database's default tablespace."),
2012                         GUC_IS_NAME
2013                 },
2014                 &default_tablespace,
2015                 "", assign_default_tablespace, NULL
2016         },
2017
2018         {
2019                 {"temp_tablespaces", PGC_USERSET, CLIENT_CONN_STATEMENT,
2020                         gettext_noop("Sets the tablespace(s) to use for temporary tables and sort files."),
2021                         NULL,
2022                         GUC_LIST_INPUT | GUC_LIST_QUOTE
2023                 },
2024                 &temp_tablespaces,
2025                 "", assign_temp_tablespaces, NULL
2026         },
2027
2028         {
2029                 {"default_transaction_isolation", PGC_USERSET, CLIENT_CONN_STATEMENT,
2030                         gettext_noop("Sets the transaction isolation level of each new transaction."),
2031                         gettext_noop("Each SQL transaction has an isolation level, which "
2032                                                  "can be either \"read uncommitted\", \"read committed\", \"repeatable read\", or \"serializable\".")
2033                 },
2034                 &default_iso_level_string,
2035                 "read committed", assign_defaultxactisolevel, NULL
2036         },
2037
2038         {
2039                 {"session_replication_role", PGC_SUSET, CLIENT_CONN_STATEMENT,
2040                         gettext_noop("Sets the sessions behavior for triggers and rewrite rules."),
2041                         gettext_noop("Each session can be either"
2042                                                  " \"origin\", \"replica\" or \"local\".")
2043                 },
2044                 &session_replication_role_string,
2045                 "origin", assign_session_replication_role, NULL
2046         },
2047
2048         {
2049                 {"dynamic_library_path", PGC_SUSET, CLIENT_CONN_OTHER,
2050                         gettext_noop("Sets the path for dynamically loadable modules."),
2051                         gettext_noop("If a dynamically loadable module needs to be opened and "
2052                                                  "the specified name does not have a directory component (i.e., the "
2053                                                  "name does not contain a slash), the system will search this path for "
2054                                                  "the specified file."),
2055                         GUC_SUPERUSER_ONLY
2056                 },
2057                 &Dynamic_library_path,
2058                 "$libdir", NULL, NULL
2059         },
2060
2061         {
2062                 {"krb_server_keyfile", PGC_POSTMASTER, CONN_AUTH_SECURITY,
2063                         gettext_noop("Sets the location of the Kerberos server key file."),
2064                         NULL,
2065                         GUC_SUPERUSER_ONLY
2066                 },
2067                 &pg_krb_server_keyfile,
2068                 PG_KRB_SRVTAB, NULL, NULL
2069         },
2070
2071         {
2072                 {"krb_srvname", PGC_POSTMASTER, CONN_AUTH_SECURITY,
2073                         gettext_noop("Sets the name of the Kerberos service."),
2074                         NULL
2075                 },
2076                 &pg_krb_srvnam,
2077                 PG_KRB_SRVNAM, NULL, NULL
2078         },
2079
2080         {
2081                 {"krb_server_hostname", PGC_POSTMASTER, CONN_AUTH_SECURITY,
2082                         gettext_noop("Sets the hostname of the Kerberos server."),
2083                         NULL
2084                 },
2085                 &pg_krb_server_hostname,
2086                 NULL, NULL, NULL
2087         },
2088
2089         {
2090                 {"bonjour_name", PGC_POSTMASTER, CONN_AUTH_SETTINGS,
2091                         gettext_noop("Sets the Bonjour broadcast service name."),
2092                         NULL
2093                 },
2094                 &bonjour_name,
2095                 "", NULL, NULL
2096         },
2097
2098         /* See main.c about why defaults for LC_foo are not all alike */
2099
2100         {
2101                 {"lc_collate", PGC_INTERNAL, CLIENT_CONN_LOCALE,
2102                         gettext_noop("Shows the collation order locale."),
2103                         NULL,
2104                         GUC_NOT_IN_SAMPLE | GUC_DISALLOW_IN_FILE
2105                 },
2106                 &locale_collate,
2107                 "C", NULL, NULL
2108         },
2109
2110         {
2111                 {"lc_ctype", PGC_INTERNAL, CLIENT_CONN_LOCALE,
2112                         gettext_noop("Shows the character classification and case conversion locale."),
2113                         NULL,
2114                         GUC_NOT_IN_SAMPLE | GUC_DISALLOW_IN_FILE
2115                 },
2116                 &locale_ctype,
2117                 "C", NULL, NULL
2118         },
2119
2120         {
2121                 {"lc_messages", PGC_SUSET, CLIENT_CONN_LOCALE,
2122                         gettext_noop("Sets the language in which messages are displayed."),
2123                         NULL
2124                 },
2125                 &locale_messages,
2126                 "", locale_messages_assign, NULL
2127         },
2128
2129         {
2130                 {"lc_monetary", PGC_USERSET, CLIENT_CONN_LOCALE,
2131                         gettext_noop("Sets the locale for formatting monetary amounts."),
2132                         NULL
2133                 },
2134                 &locale_monetary,
2135                 "C", locale_monetary_assign, NULL
2136         },
2137
2138         {
2139                 {"lc_numeric", PGC_USERSET, CLIENT_CONN_LOCALE,
2140                         gettext_noop("Sets the locale for formatting numbers."),
2141                         NULL
2142                 },
2143                 &locale_numeric,
2144                 "C", locale_numeric_assign, NULL
2145         },
2146
2147         {
2148                 {"lc_time", PGC_USERSET, CLIENT_CONN_LOCALE,
2149                         gettext_noop("Sets the locale for formatting date and time values."),
2150                         NULL
2151                 },
2152                 &locale_time,
2153                 "C", locale_time_assign, NULL
2154         },
2155
2156         {
2157                 {"shared_preload_libraries", PGC_POSTMASTER, RESOURCES_KERNEL,
2158                         gettext_noop("Lists shared libraries to preload into server."),
2159                         NULL,
2160                         GUC_LIST_INPUT | GUC_LIST_QUOTE | GUC_SUPERUSER_ONLY
2161                 },
2162                 &shared_preload_libraries_string,
2163                 "", NULL, NULL
2164         },
2165
2166         {
2167                 {"local_preload_libraries", PGC_BACKEND, CLIENT_CONN_OTHER,
2168                         gettext_noop("Lists shared libraries to preload into each backend."),
2169                         NULL,
2170                         GUC_LIST_INPUT | GUC_LIST_QUOTE
2171                 },
2172                 &local_preload_libraries_string,
2173                 "", NULL, NULL
2174         },
2175
2176         {
2177                 {"regex_flavor", PGC_USERSET, COMPAT_OPTIONS_PREVIOUS,
2178                         gettext_noop("Sets the regular expression \"flavor\"."),
2179                         gettext_noop("This can be set to advanced, extended, or basic.")
2180                 },
2181                 &regex_flavor_string,
2182                 "advanced", assign_regex_flavor, NULL
2183         },
2184
2185         {
2186                 {"search_path", PGC_USERSET, CLIENT_CONN_STATEMENT,
2187                         gettext_noop("Sets the schema search order for names that are not schema-qualified."),
2188                         NULL,
2189                         GUC_LIST_INPUT | GUC_LIST_QUOTE
2190                 },
2191                 &namespace_search_path,
2192                 "\"$user\",public", assign_search_path, NULL
2193         },
2194
2195         {
2196                 /* Can't be set in postgresql.conf */
2197                 {"server_encoding", PGC_INTERNAL, CLIENT_CONN_LOCALE,
2198                         gettext_noop("Sets the server (database) character set encoding."),
2199                         NULL,
2200                         GUC_IS_NAME | GUC_REPORT | GUC_NOT_IN_SAMPLE | GUC_DISALLOW_IN_FILE
2201                 },
2202                 &server_encoding_string,
2203                 "SQL_ASCII", NULL, NULL
2204         },
2205
2206         {
2207                 /* Can't be set in postgresql.conf */
2208                 {"server_version", PGC_INTERNAL, PRESET_OPTIONS,
2209                         gettext_noop("Shows the server version."),
2210                         NULL,
2211                         GUC_REPORT | GUC_NOT_IN_SAMPLE | GUC_DISALLOW_IN_FILE
2212                 },
2213                 &server_version_string,
2214                 PG_VERSION, NULL, NULL
2215         },
2216
2217         {
2218                 /* Not for general use --- used by SET ROLE */
2219                 {"role", PGC_USERSET, UNGROUPED,
2220                         gettext_noop("Sets the current role."),
2221                         NULL,
2222                         GUC_IS_NAME | GUC_NO_SHOW_ALL | GUC_NO_RESET_ALL | GUC_NOT_IN_SAMPLE | GUC_DISALLOW_IN_FILE
2223                 },
2224                 &role_string,
2225                 "none", assign_role, show_role
2226         },
2227
2228         {
2229                 /* Not for general use --- used by SET SESSION AUTHORIZATION */
2230                 {"session_authorization", PGC_USERSET, UNGROUPED,
2231                         gettext_noop("Sets the session user name."),
2232                         NULL,
2233                         GUC_IS_NAME | GUC_REPORT | GUC_NO_SHOW_ALL | GUC_NO_RESET_ALL | GUC_NOT_IN_SAMPLE | GUC_DISALLOW_IN_FILE
2234                 },
2235                 &session_authorization_string,
2236                 NULL, assign_session_authorization, show_session_authorization
2237         },
2238
2239         {
2240                 {"log_destination", PGC_SIGHUP, LOGGING_WHERE,
2241                         gettext_noop("Sets the destination for server log output."),
2242                         gettext_noop("Valid values are combinations of \"stderr\", \"syslog\", "
2243                                                  "and \"eventlog\", depending on the platform."),
2244                         GUC_LIST_INPUT
2245                 },
2246                 &log_destination_string,
2247                 "stderr", assign_log_destination, NULL
2248         },
2249         {
2250                 {"log_directory", PGC_SIGHUP, LOGGING_WHERE,
2251                         gettext_noop("Sets the destination directory for log files."),
2252                         gettext_noop("Can be specified as relative to the data directory "
2253                                                  "or as absolute path."),
2254                         GUC_SUPERUSER_ONLY
2255                 },
2256                 &Log_directory,
2257                 "pg_log", assign_canonical_path, NULL
2258         },
2259         {
2260                 {"log_filename", PGC_SIGHUP, LOGGING_WHERE,
2261                         gettext_noop("Sets the file name pattern for log files."),
2262                         NULL,
2263                         GUC_SUPERUSER_ONLY
2264                 },
2265                 &Log_filename,
2266                 "postgresql-%Y-%m-%d_%H%M%S.log", NULL, NULL
2267         },
2268
2269 #ifdef HAVE_SYSLOG
2270         {
2271                 {"syslog_facility", PGC_SIGHUP, LOGGING_WHERE,
2272                         gettext_noop("Sets the syslog \"facility\" to be used when syslog enabled."),
2273                         gettext_noop("Valid values are LOCAL0, LOCAL1, LOCAL2, LOCAL3, "
2274                                                  "LOCAL4, LOCAL5, LOCAL6, LOCAL7.")
2275                 },
2276                 &syslog_facility_str,
2277                 "LOCAL0", assign_syslog_facility, NULL
2278         },
2279         {
2280                 {"syslog_ident", PGC_SIGHUP, LOGGING_WHERE,
2281                         gettext_noop("Sets the program name used to identify PostgreSQL "
2282                                                  "messages in syslog."),
2283                         NULL
2284                 },
2285                 &syslog_ident_str,
2286                 "postgres", assign_syslog_ident, NULL
2287         },
2288 #endif
2289
2290         {
2291                 {"TimeZone", PGC_USERSET, CLIENT_CONN_LOCALE,
2292                         gettext_noop("Sets the time zone for displaying and interpreting time stamps."),
2293                         NULL,
2294                         GUC_REPORT
2295                 },
2296                 &timezone_string,
2297                 "UNKNOWN", assign_timezone, show_timezone
2298         },
2299         {
2300                 {"timezone_abbreviations", PGC_USERSET, CLIENT_CONN_LOCALE,
2301                         gettext_noop("Selects a file of time zone abbreviations."),
2302                         NULL,
2303                 },
2304                 &timezone_abbreviations_string,
2305                 "UNKNOWN", assign_timezone_abbreviations, NULL
2306         },
2307
2308         {
2309                 {"transaction_isolation", PGC_USERSET, CLIENT_CONN_STATEMENT,
2310                         gettext_noop("Sets the current transaction's isolation level."),
2311                         NULL,
2312                         GUC_NO_RESET_ALL | GUC_NOT_IN_SAMPLE | GUC_DISALLOW_IN_FILE
2313                 },
2314                 &XactIsoLevel_string,
2315                 NULL, assign_XactIsoLevel, show_XactIsoLevel
2316         },
2317
2318         {
2319                 {"unix_socket_group", PGC_POSTMASTER, CONN_AUTH_SETTINGS,
2320                         gettext_noop("Sets the owning group of the Unix-domain socket."),
2321                         gettext_noop("The owning user of the socket is always the user "
2322                                                  "that starts the server.")
2323                 },
2324                 &Unix_socket_group,
2325                 "", NULL, NULL
2326         },
2327
2328         {
2329                 {"unix_socket_directory", PGC_POSTMASTER, CONN_AUTH_SETTINGS,
2330                         gettext_noop("Sets the directory where the Unix-domain socket will be created."),
2331                         NULL,
2332                         GUC_SUPERUSER_ONLY
2333                 },
2334                 &UnixSocketDir,
2335                 "", assign_canonical_path, NULL
2336         },
2337
2338         {
2339                 {"listen_addresses", PGC_POSTMASTER, CONN_AUTH_SETTINGS,
2340                         gettext_noop("Sets the host name or IP address(es) to listen to."),
2341                         NULL,
2342                         GUC_LIST_INPUT
2343                 },
2344                 &ListenAddresses,
2345                 "localhost", NULL, NULL
2346         },
2347
2348         {
2349                 {"wal_sync_method", PGC_SIGHUP, WAL_SETTINGS,
2350                         gettext_noop("Selects the method used for forcing WAL updates to disk."),
2351                         NULL
2352                 },
2353                 &XLOG_sync_method,
2354                 XLOG_sync_method_default, assign_xlog_sync_method, NULL
2355         },
2356
2357         {
2358                 {"custom_variable_classes", PGC_SIGHUP, CUSTOM_OPTIONS,
2359                         gettext_noop("Sets the list of known custom variable classes."),
2360                         NULL,
2361                         GUC_LIST_INPUT | GUC_LIST_QUOTE
2362                 },
2363                 &custom_variable_classes,
2364                 NULL, assign_custom_variable_classes, NULL
2365         },
2366
2367         {
2368                 {"data_directory", PGC_POSTMASTER, FILE_LOCATIONS,
2369                         gettext_noop("Sets the server's data directory."),
2370                         NULL,
2371                         GUC_SUPERUSER_ONLY
2372                 },
2373                 &data_directory,
2374                 NULL, NULL, NULL
2375         },
2376
2377         {
2378                 {"config_file", PGC_POSTMASTER, FILE_LOCATIONS,
2379                         gettext_noop("Sets the server's main configuration file."),
2380                         NULL,
2381                         GUC_DISALLOW_IN_FILE | GUC_SUPERUSER_ONLY
2382                 },
2383                 &ConfigFileName,
2384                 NULL, NULL, NULL
2385         },
2386
2387         {
2388                 {"hba_file", PGC_POSTMASTER, FILE_LOCATIONS,
2389                         gettext_noop("Sets the server's \"hba\" configuration file."),
2390                         NULL,
2391                         GUC_SUPERUSER_ONLY
2392                 },
2393                 &HbaFileName,
2394                 NULL, NULL, NULL
2395         },
2396
2397         {
2398                 {"ident_file", PGC_POSTMASTER, FILE_LOCATIONS,
2399                         gettext_noop("Sets the server's \"ident\" configuration file."),
2400                         NULL,
2401                         GUC_SUPERUSER_ONLY
2402                 },
2403                 &IdentFileName,
2404                 NULL, NULL, NULL
2405         },
2406
2407         {
2408                 {"external_pid_file", PGC_POSTMASTER, FILE_LOCATIONS,
2409                         gettext_noop("Writes the postmaster PID to the specified file."),
2410                         NULL,
2411                         GUC_SUPERUSER_ONLY
2412                 },
2413                 &external_pid_file,
2414                 NULL, assign_canonical_path, NULL
2415         },
2416
2417         {
2418                 {"xmlbinary", PGC_USERSET, CLIENT_CONN_STATEMENT,
2419                         gettext_noop("Sets how binary values are to be encoded in XML."),
2420                         gettext_noop("Valid values are BASE64 and HEX.")
2421                 },
2422                 &xmlbinary_string,
2423                 "base64", assign_xmlbinary, NULL
2424         },
2425
2426         {
2427                 {"xmloption", PGC_USERSET, CLIENT_CONN_STATEMENT,
2428                         gettext_noop("Sets whether XML data in implicit parsing and serialization "
2429                                                  "operations is to be considered as documents or content fragments."),
2430                         gettext_noop("Valid values are DOCUMENT and CONTENT.")
2431                 },
2432                 &xmloption_string,
2433                 "content", assign_xmloption, NULL
2434         },
2435
2436 #ifdef USE_SSL
2437         {
2438                 {"ssl_ciphers", PGC_POSTMASTER, CONN_AUTH_SECURITY,
2439                         gettext_noop("Sets the list of allowed SSL ciphers."),
2440                         NULL,
2441                         GUC_SUPERUSER_ONLY
2442                 },
2443                 &SSLCipherSuites,
2444                 "ALL:!ADH:!LOW:!EXP:!MD5:@STRENGTH", NULL, NULL
2445         },
2446 #endif /* USE_SSL */
2447
2448         /* End-of-list marker */
2449         {
2450                 {NULL, 0, 0, NULL, NULL}, NULL, NULL, NULL, NULL
2451         }
2452 };
2453
2454
2455 /******** end of options list ********/
2456
2457
2458 /*
2459  * To allow continued support of obsolete names for GUC variables, we apply
2460  * the following mappings to any unrecognized name.  Note that an old name
2461  * should be mapped to a new one only if the new variable has very similar
2462  * semantics to the old.
2463  */
2464 static const char *const map_old_guc_names[] = {
2465         "sort_mem", "work_mem",
2466         "vacuum_mem", "maintenance_work_mem",
2467         NULL
2468 };
2469
2470
2471 /*
2472  * Actual lookup of variables is done through this single, sorted array.
2473  */
2474 static struct config_generic **guc_variables;
2475
2476 /* Current number of variables contained in the vector */
2477 static int      num_guc_variables;
2478
2479 /* Vector capacity */
2480 static int      size_guc_variables;
2481
2482
2483 static bool guc_dirty;                  /* TRUE if need to do commit/abort work */
2484
2485 static bool reporting_enabled;  /* TRUE to enable GUC_REPORT */
2486
2487
2488 static int      guc_var_compare(const void *a, const void *b);
2489 static int      guc_name_compare(const char *namea, const char *nameb);
2490 static void push_old_value(struct config_generic * gconf);
2491 static void ReportGUCOption(struct config_generic * record);
2492 static void ShowGUCConfigOption(const char *name, DestReceiver *dest);
2493 static void ShowAllGUCConfig(DestReceiver *dest);
2494 static char *_ShowOption(struct config_generic * record, bool use_units);
2495 static bool is_newvalue_equal(struct config_generic * record, const char *newvalue);
2496
2497
2498 /*
2499  * Some infrastructure for checking malloc/strdup/realloc calls
2500  */
2501 static void *
2502 guc_malloc(int elevel, size_t size)
2503 {
2504         void       *data;
2505
2506         data = malloc(size);
2507         if (data == NULL)
2508                 ereport(elevel,
2509                                 (errcode(ERRCODE_OUT_OF_MEMORY),
2510                                  errmsg("out of memory")));
2511         return data;
2512 }
2513
2514 static void *
2515 guc_realloc(int elevel, void *old, size_t size)
2516 {
2517         void       *data;
2518
2519         data = realloc(old, size);
2520         if (data == NULL)
2521                 ereport(elevel,
2522                                 (errcode(ERRCODE_OUT_OF_MEMORY),
2523                                  errmsg("out of memory")));
2524         return data;
2525 }
2526
2527 static char *
2528 guc_strdup(int elevel, const char *src)
2529 {
2530         char       *data;
2531
2532         data = strdup(src);
2533         if (data == NULL)
2534                 ereport(elevel,
2535                                 (errcode(ERRCODE_OUT_OF_MEMORY),
2536                                  errmsg("out of memory")));
2537         return data;
2538 }
2539
2540
2541 /*
2542  * Support for assigning to a field of a string GUC item.  Free the prior
2543  * value if it's not referenced anywhere else in the item (including stacked
2544  * states).
2545  */
2546 static void
2547 set_string_field(struct config_string * conf, char **field, char *newval)
2548 {
2549         char       *oldval = *field;
2550         GucStack   *stack;
2551
2552         /* Do the assignment */
2553         *field = newval;
2554
2555         /* Exit if any duplicate references, or if old value was NULL anyway */
2556         if (oldval == NULL ||
2557                 oldval == *(conf->variable) ||
2558                 oldval == conf->reset_val ||
2559                 oldval == conf->tentative_val ||
2560                 oldval == conf->boot_val)
2561                 return;
2562         for (stack = conf->gen.stack; stack; stack = stack->prev)
2563         {
2564                 if (oldval == stack->tentative_val.stringval ||
2565                         oldval == stack->value.stringval)
2566                         return;
2567         }
2568
2569         /* Not used anymore, so free it */
2570         free(oldval);
2571 }
2572
2573 /*
2574  * Detect whether strval is referenced anywhere in a GUC string item
2575  */
2576 static bool
2577 string_field_used(struct config_string * conf, char *strval)
2578 {
2579         GucStack   *stack;
2580
2581         if (strval == *(conf->variable) ||
2582                 strval == conf->reset_val ||
2583                 strval == conf->tentative_val ||
2584                 strval == conf->boot_val)
2585                 return true;
2586         for (stack = conf->gen.stack; stack; stack = stack->prev)
2587         {
2588                 if (strval == stack->tentative_val.stringval ||
2589                         strval == stack->value.stringval)
2590                         return true;
2591         }
2592         return false;
2593 }
2594
2595
2596 struct config_generic **
2597 get_guc_variables(void)
2598 {
2599         return guc_variables;
2600 }
2601
2602
2603 /*
2604  * Build the sorted array.      This is split out so that it could be
2605  * re-executed after startup (eg, we could allow loadable modules to
2606  * add vars, and then we'd need to re-sort).
2607  */
2608 void
2609 build_guc_variables(void)
2610 {
2611         int                     size_vars;
2612         int                     num_vars = 0;
2613         struct config_generic **guc_vars;
2614         int                     i;
2615
2616         for (i = 0; ConfigureNamesBool[i].gen.name; i++)
2617         {
2618                 struct config_bool *conf = &ConfigureNamesBool[i];
2619
2620                 /* Rather than requiring vartype to be filled in by hand, do this: */
2621                 conf->gen.vartype = PGC_BOOL;
2622                 num_vars++;
2623         }
2624
2625         for (i = 0; ConfigureNamesInt[i].gen.name; i++)
2626         {
2627                 struct config_int *conf = &ConfigureNamesInt[i];
2628
2629                 conf->gen.vartype = PGC_INT;
2630                 num_vars++;
2631         }
2632
2633         for (i = 0; ConfigureNamesReal[i].gen.name; i++)
2634         {
2635                 struct config_real *conf = &ConfigureNamesReal[i];
2636
2637                 conf->gen.vartype = PGC_REAL;
2638                 num_vars++;
2639         }
2640
2641         for (i = 0; ConfigureNamesString[i].gen.name; i++)
2642         {
2643                 struct config_string *conf = &ConfigureNamesString[i];
2644
2645                 conf->gen.vartype = PGC_STRING;
2646                 num_vars++;
2647         }
2648
2649         /*
2650          * Create table with 20% slack
2651          */
2652         size_vars = num_vars + num_vars / 4;
2653
2654         guc_vars = (struct config_generic **)
2655                 guc_malloc(FATAL, size_vars * sizeof(struct config_generic *));
2656
2657         num_vars = 0;
2658
2659         for (i = 0; ConfigureNamesBool[i].gen.name; i++)
2660                 guc_vars[num_vars++] = &ConfigureNamesBool[i].gen;
2661
2662         for (i = 0; ConfigureNamesInt[i].gen.name; i++)
2663                 guc_vars[num_vars++] = &ConfigureNamesInt[i].gen;
2664
2665         for (i = 0; ConfigureNamesReal[i].gen.name; i++)
2666                 guc_vars[num_vars++] = &ConfigureNamesReal[i].gen;
2667
2668         for (i = 0; ConfigureNamesString[i].gen.name; i++)
2669                 guc_vars[num_vars++] = &ConfigureNamesString[i].gen;
2670
2671         if (guc_variables)
2672                 free(guc_variables);
2673         guc_variables = guc_vars;
2674         num_guc_variables = num_vars;
2675         size_guc_variables = size_vars;
2676         qsort((void *) guc_variables, num_guc_variables,
2677                   sizeof(struct config_generic *), guc_var_compare);
2678 }
2679
2680 static bool
2681 is_custom_class(const char *name, int dotPos)
2682 {
2683         /*
2684          * assign_custom_variable_classes() has made sure no empty identifiers or
2685          * whitespace exists in the variable
2686          */
2687         bool            result = false;
2688         const char *ccs = GetConfigOption("custom_variable_classes");
2689
2690         if (ccs != NULL)
2691         {
2692                 const char *start = ccs;
2693
2694                 for (;; ++ccs)
2695                 {
2696                         int                     c = *ccs;
2697
2698                         if (c == 0 || c == ',')
2699                         {
2700                                 if (dotPos == ccs - start && strncmp(start, name, dotPos) == 0)
2701                                 {
2702                                         result = true;
2703                                         break;
2704                                 }
2705                                 if (c == 0)
2706                                         break;
2707                                 start = ccs + 1;
2708                         }
2709                 }
2710         }
2711         return result;
2712 }
2713
2714 /*
2715  * Add a new GUC variable to the list of known variables. The
2716  * list is expanded if needed.
2717  */
2718 static bool
2719 add_guc_variable(struct config_generic * var, int elevel)
2720 {
2721         if (num_guc_variables + 1 >= size_guc_variables)
2722         {
2723                 /*
2724                  * Increase the vector by 25%
2725                  */
2726                 int                     size_vars = size_guc_variables + size_guc_variables / 4;
2727                 struct config_generic **guc_vars;
2728
2729                 if (size_vars == 0)
2730                 {
2731                         size_vars = 100;
2732                         guc_vars = (struct config_generic **)
2733                                 guc_malloc(elevel, size_vars * sizeof(struct config_generic *));
2734                 }
2735                 else
2736                 {
2737                         guc_vars = (struct config_generic **)
2738                                 guc_realloc(elevel, guc_variables, size_vars * sizeof(struct config_generic *));
2739                 }
2740
2741                 if (guc_vars == NULL)
2742                         return false;           /* out of memory */
2743
2744                 guc_variables = guc_vars;
2745                 size_guc_variables = size_vars;
2746         }
2747         guc_variables[num_guc_variables++] = var;
2748         qsort((void *) guc_variables, num_guc_variables,
2749                   sizeof(struct config_generic *), guc_var_compare);
2750         return true;
2751 }
2752
2753 /*
2754  * Create and add a placeholder variable. It's presumed to belong
2755  * to a valid custom variable class at this point.
2756  */
2757 static struct config_string *
2758 add_placeholder_variable(const char *name, int elevel)
2759 {
2760         size_t          sz = sizeof(struct config_string) + sizeof(char *);
2761         struct config_string *var;
2762         struct config_generic *gen;
2763
2764         var = (struct config_string *) guc_malloc(elevel, sz);
2765         if (var == NULL)
2766                 return NULL;
2767
2768         gen = &var->gen;
2769         memset(var, 0, sz);
2770
2771         gen->name = guc_strdup(elevel, name);
2772         if (gen->name == NULL)
2773         {
2774                 free(var);
2775                 return NULL;
2776         }
2777
2778         gen->context = PGC_USERSET;
2779         gen->group = CUSTOM_OPTIONS;
2780         gen->short_desc = "GUC placeholder variable";
2781         gen->flags = GUC_NO_SHOW_ALL | GUC_NOT_IN_SAMPLE | GUC_CUSTOM_PLACEHOLDER;
2782         gen->vartype = PGC_STRING;
2783
2784         /*
2785          * The char* is allocated at the end of the struct since we have no
2786          * 'static' place to point to.
2787          */
2788         var->variable = (char **) (var + 1);
2789
2790         if (!add_guc_variable((struct config_generic *) var, elevel))
2791         {
2792                 free((void *) gen->name);
2793                 free(var);
2794                 return NULL;
2795         }
2796
2797         return var;
2798 }
2799
2800 /*
2801  * Look up option NAME. If it exists, return a pointer to its record,
2802  * else return NULL.
2803  */
2804 static struct config_generic *
2805 find_option(const char *name, int elevel)
2806 {
2807         const char *dot;
2808         const char **key = &name;
2809         struct config_generic **res;
2810         int                     i;
2811
2812         Assert(name);
2813
2814         /*
2815          * By equating const char ** with struct config_generic *, we are assuming
2816          * the name field is first in config_generic.
2817          */
2818         res = (struct config_generic **) bsearch((void *) &key,
2819                                                                                          (void *) guc_variables,
2820                                                                                          num_guc_variables,
2821                                                                                          sizeof(struct config_generic *),
2822                                                                                          guc_var_compare);
2823         if (res)
2824                 return *res;
2825
2826         /*
2827          * See if the name is an obsolete name for a variable.  We assume that the
2828          * set of supported old names is short enough that a brute-force search is
2829          * the best way.
2830          */
2831         for (i = 0; map_old_guc_names[i] != NULL; i += 2)
2832         {
2833                 if (guc_name_compare(name, map_old_guc_names[i]) == 0)
2834                         return find_option(map_old_guc_names[i + 1], elevel);
2835         }
2836
2837         /*
2838          * Check if the name is qualified, and if so, check if the qualifier maps
2839          * to a custom variable class.
2840          */
2841         dot = strchr(name, GUC_QUALIFIER_SEPARATOR);
2842         if (dot != NULL && is_custom_class(name, dot - name))
2843                 /* Add a placeholder variable for this name */
2844                 return (struct config_generic *) add_placeholder_variable(name, elevel);
2845
2846         /* Unknown name */
2847         return NULL;
2848 }
2849
2850
2851 /*
2852  * comparator for qsorting and bsearching guc_variables array
2853  */
2854 static int
2855 guc_var_compare(const void *a, const void *b)
2856 {
2857         struct config_generic *confa = *(struct config_generic **) a;
2858         struct config_generic *confb = *(struct config_generic **) b;
2859
2860         return guc_name_compare(confa->name, confb->name);
2861 }
2862
2863
2864 static int
2865 guc_name_compare(const char *namea, const char *nameb)
2866 {
2867         /*
2868          * The temptation to use strcasecmp() here must be resisted, because the
2869          * array ordering has to remain stable across setlocale() calls. So, build
2870          * our own with a simple ASCII-only downcasing.
2871          */
2872         while (*namea && *nameb)
2873         {
2874                 char            cha = *namea++;
2875                 char            chb = *nameb++;
2876
2877                 if (cha >= 'A' && cha <= 'Z')
2878                         cha += 'a' - 'A';
2879                 if (chb >= 'A' && chb <= 'Z')
2880                         chb += 'a' - 'A';
2881                 if (cha != chb)
2882                         return cha - chb;
2883         }
2884         if (*namea)
2885                 return 1;                               /* a is longer */
2886         if (*nameb)
2887                 return -1;                              /* b is longer */
2888         return 0;
2889 }
2890
2891
2892 static int
2893 guc_get_index(const char *name)
2894 {
2895         const char **key = &name;
2896         struct config_generic **res;
2897
2898         Assert(name);
2899
2900         /*
2901          * By equating const char ** with struct config_generic *, we are assuming
2902          * the name field is first in config_generic.
2903          */
2904         res = (struct config_generic **) bsearch((void *) &key,
2905                                                                                          (void *) guc_variables,
2906                                                                                          num_guc_variables,
2907                                                                                          sizeof(struct config_generic *),
2908                                                                                          guc_var_compare);
2909         if (!res)
2910                 return -1;
2911
2912         return res - guc_variables;
2913 }
2914
2915
2916 /*
2917  * Initialize GUC options during program startup.
2918  *
2919  * Note that we cannot read the config file yet, since we have not yet
2920  * processed command-line switches.
2921  */
2922 void
2923 InitializeGUCOptions(void)
2924 {
2925         int                     i;
2926         char       *env;
2927         long            stack_rlimit;
2928
2929         /*
2930          * Before log_line_prefix could possibly receive a nonempty setting,
2931          * make sure that timezone processing is minimally alive (see elog.c).
2932          */
2933         pg_timezone_pre_initialize();
2934
2935         /*
2936          * Build sorted array of all GUC variables.
2937          */
2938         build_guc_variables();
2939
2940         /*
2941          * Load all variables with their compiled-in defaults, and initialize
2942          * status fields as needed.
2943          */
2944         for (i = 0; i < num_guc_variables; i++)
2945         {
2946                 struct config_generic *gconf = guc_variables[i];
2947
2948                 gconf->status = 0;
2949                 gconf->reset_source = PGC_S_DEFAULT;
2950                 gconf->tentative_source = PGC_S_DEFAULT;
2951                 gconf->source = PGC_S_DEFAULT;
2952                 gconf->stack = NULL;
2953
2954                 switch (gconf->vartype)
2955                 {
2956                         case PGC_BOOL:
2957                                 {
2958                                         struct config_bool *conf = (struct config_bool *) gconf;
2959
2960                                         if (conf->assign_hook)
2961                                                 if (!(*conf->assign_hook) (conf->boot_val, true,
2962                                                                                                    PGC_S_DEFAULT))
2963                                                         elog(FATAL, "failed to initialize %s to %d",
2964                                                                  conf->gen.name, (int) conf->boot_val);
2965                                         *conf->variable = conf->reset_val = conf->boot_val;
2966                                         break;
2967                                 }
2968                         case PGC_INT:
2969                                 {
2970                                         struct config_int *conf = (struct config_int *) gconf;
2971
2972                                         Assert(conf->boot_val >= conf->min);
2973                                         Assert(conf->boot_val <= conf->max);
2974                                         if (conf->assign_hook)
2975                                                 if (!(*conf->assign_hook) (conf->boot_val, true,
2976                                                                                                    PGC_S_DEFAULT))
2977                                                         elog(FATAL, "failed to initialize %s to %d",
2978                                                                  conf->gen.name, conf->boot_val);
2979                                         *conf->variable = conf->reset_val = conf->boot_val;
2980                                         break;
2981                                 }
2982                         case PGC_REAL:
2983                                 {
2984                                         struct config_real *conf = (struct config_real *) gconf;
2985
2986                                         Assert(conf->boot_val >= conf->min);
2987                                         Assert(conf->boot_val <= conf->max);
2988                                         if (conf->assign_hook)
2989                                                 if (!(*conf->assign_hook) (conf->boot_val, true,
2990                                                                                                    PGC_S_DEFAULT))
2991                                                         elog(FATAL, "failed to initialize %s to %g",
2992                                                                  conf->gen.name, conf->boot_val);
2993                                         *conf->variable = conf->reset_val = conf->boot_val;
2994                                         break;
2995                                 }
2996                         case PGC_STRING:
2997                                 {
2998                                         struct config_string *conf = (struct config_string *) gconf;
2999                                         char       *str;
3000
3001                                         *conf->variable = NULL;
3002                                         conf->reset_val = NULL;
3003                                         conf->tentative_val = NULL;
3004
3005                                         if (conf->boot_val == NULL)
3006                                         {
3007                                                 /* Cannot set value yet */
3008                                                 break;
3009                                         }
3010
3011                                         str = guc_strdup(FATAL, conf->boot_val);
3012                                         conf->reset_val = str;
3013
3014                                         if (conf->assign_hook)
3015                                         {
3016                                                 const char *newstr;
3017
3018                                                 newstr = (*conf->assign_hook) (str, true,
3019                                                                                                            PGC_S_DEFAULT);
3020                                                 if (newstr == NULL)
3021                                                 {
3022                                                         elog(FATAL, "failed to initialize %s to \"%s\"",
3023                                                                  conf->gen.name, str);
3024                                                 }
3025                                                 else if (newstr != str)
3026                                                 {
3027                                                         free(str);
3028
3029                                                         /*
3030                                                          * See notes in set_config_option about casting
3031                                                          */
3032                                                         str = (char *) newstr;
3033                                                         conf->reset_val = str;
3034                                                 }
3035                                         }
3036                                         *conf->variable = str;
3037                                         break;
3038                                 }
3039                 }
3040         }
3041
3042         guc_dirty = false;
3043
3044         reporting_enabled = false;
3045
3046         /*
3047          * Prevent any attempt to override the transaction modes from
3048          * non-interactive sources.
3049          */
3050         SetConfigOption("transaction_isolation", "default",
3051                                         PGC_POSTMASTER, PGC_S_OVERRIDE);
3052         SetConfigOption("transaction_read_only", "no",
3053                                         PGC_POSTMASTER, PGC_S_OVERRIDE);
3054
3055         /*
3056          * For historical reasons, some GUC parameters can receive defaults from
3057          * environment variables.  Process those settings.
3058          */
3059
3060         env = getenv("PGPORT");
3061         if (env != NULL)
3062                 SetConfigOption("port", env, PGC_POSTMASTER, PGC_S_ENV_VAR);
3063
3064         env = getenv("PGDATESTYLE");
3065         if (env != NULL)
3066                 SetConfigOption("datestyle", env, PGC_POSTMASTER, PGC_S_ENV_VAR);
3067
3068         env = getenv("PGCLIENTENCODING");
3069         if (env != NULL)
3070                 SetConfigOption("client_encoding", env, PGC_POSTMASTER, PGC_S_ENV_VAR);
3071
3072         /*
3073          * rlimit isn't exactly an "environment variable", but it behaves about
3074          * the same.  If we can identify the platform stack depth rlimit, increase
3075          * default stack depth setting up to whatever is safe (but at most 2MB).
3076          */
3077         stack_rlimit = get_stack_depth_rlimit();
3078         if (stack_rlimit > 0)
3079         {
3080                 int             new_limit = (stack_rlimit - STACK_DEPTH_SLOP) / 1024L;
3081
3082                 if (new_limit > 100)
3083                 {
3084                         char    limbuf[16];
3085
3086                         new_limit = Min(new_limit, 2048);
3087                         sprintf(limbuf, "%d", new_limit);
3088                         SetConfigOption("max_stack_depth", limbuf,
3089                                                         PGC_POSTMASTER, PGC_S_ENV_VAR);
3090                 }
3091         }
3092 }
3093
3094
3095 /*
3096  * Select the configuration files and data directory to be used, and
3097  * do the initial read of postgresql.conf.
3098  *
3099  * This is called after processing command-line switches.
3100  *              userDoption is the -D switch value if any (NULL if unspecified).
3101  *              progname is just for use in error messages.
3102  *
3103  * Returns true on success; on failure, prints a suitable error message
3104  * to stderr and returns false.
3105  */
3106 bool
3107 SelectConfigFiles(const char *userDoption, const char *progname)
3108 {
3109         char       *configdir;
3110         char       *fname;
3111         struct stat stat_buf;
3112
3113         /* configdir is -D option, or $PGDATA if no -D */
3114         if (userDoption)
3115                 configdir = make_absolute_path(userDoption);
3116         else
3117                 configdir = make_absolute_path(getenv("PGDATA"));
3118
3119         /*
3120          * Find the configuration file: if config_file was specified on the
3121          * command line, use it, else use configdir/postgresql.conf.  In any case
3122          * ensure the result is an absolute path, so that it will be interpreted
3123          * the same way by future backends.
3124          */
3125         if (ConfigFileName)
3126                 fname = make_absolute_path(ConfigFileName);
3127         else if (configdir)
3128         {
3129                 fname = guc_malloc(FATAL,
3130                                                    strlen(configdir) + strlen(CONFIG_FILENAME) + 2);
3131                 sprintf(fname, "%s/%s", configdir, CONFIG_FILENAME);
3132         }
3133         else
3134         {
3135                 write_stderr("%s does not know where to find the server configuration file.\n"
3136                                          "You must specify the --config-file or -D invocation "
3137                                          "option or set the PGDATA environment variable.\n",
3138                                          progname);
3139                 return false;
3140         }
3141
3142         /*
3143          * Set the ConfigFileName GUC variable to its final value, ensuring that
3144          * it can't be overridden later.
3145          */
3146         SetConfigOption("config_file", fname, PGC_POSTMASTER, PGC_S_OVERRIDE);
3147         free(fname);
3148
3149         /*
3150          * Now read the config file for the first time.
3151          */
3152         if (stat(ConfigFileName, &stat_buf) != 0)
3153         {
3154                 write_stderr("%s cannot access the server configuration file \"%s\": %s\n",
3155                                          progname, ConfigFileName, strerror(errno));
3156                 return false;
3157         }
3158
3159         ProcessConfigFile(PGC_POSTMASTER);
3160
3161         /*
3162          * If the data_directory GUC variable has been set, use that as DataDir;
3163          * otherwise use configdir if set; else punt.
3164          *
3165          * Note: SetDataDir will copy and absolute-ize its argument, so we don't
3166          * have to.
3167          */
3168         if (data_directory)
3169                 SetDataDir(data_directory);
3170         else if (configdir)
3171                 SetDataDir(configdir);
3172         else
3173         {
3174                 write_stderr("%s does not know where to find the database system data.\n"
3175                                          "This can be specified as \"data_directory\" in \"%s\", "
3176                                          "or by the -D invocation option, or by the "
3177                                          "PGDATA environment variable.\n",
3178                                          progname, ConfigFileName);
3179                 return false;
3180         }
3181
3182         /*
3183          * Reflect the final DataDir value back into the data_directory GUC var.
3184          * (If you are wondering why we don't just make them a single variable,
3185          * it's because the EXEC_BACKEND case needs DataDir to be transmitted to
3186          * child backends specially.  XXX is that still true?  Given that we now
3187          * chdir to DataDir, EXEC_BACKEND can read the config file without knowing
3188          * DataDir in advance.)
3189          */
3190         SetConfigOption("data_directory", DataDir, PGC_POSTMASTER, PGC_S_OVERRIDE);
3191
3192         /*
3193          * Figure out where pg_hba.conf is, and make sure the path is absolute.
3194          */
3195         if (HbaFileName)
3196                 fname = make_absolute_path(HbaFileName);
3197         else if (configdir)
3198         {
3199                 fname = guc_malloc(FATAL,
3200                                                    strlen(configdir) + strlen(HBA_FILENAME) + 2);
3201                 sprintf(fname, "%s/%s", configdir, HBA_FILENAME);
3202         }
3203         else
3204         {
3205                 write_stderr("%s does not know where to find the \"hba\" configuration file.\n"
3206                                          "This can be specified as \"hba_file\" in \"%s\", "
3207                                          "or by the -D invocation option, or by the "
3208                                          "PGDATA environment variable.\n",
3209                                          progname, ConfigFileName);
3210                 return false;
3211         }
3212         SetConfigOption("hba_file", fname, PGC_POSTMASTER, PGC_S_OVERRIDE);
3213         free(fname);
3214
3215         /*
3216          * Likewise for pg_ident.conf.
3217          */
3218         if (IdentFileName)
3219                 fname = make_absolute_path(IdentFileName);
3220         else if (configdir)
3221         {
3222                 fname = guc_malloc(FATAL,
3223                                                    strlen(configdir) + strlen(IDENT_FILENAME) + 2);
3224                 sprintf(fname, "%s/%s", configdir, IDENT_FILENAME);
3225         }
3226         else
3227         {
3228                 write_stderr("%s does not know where to find the \"ident\" configuration file.\n"
3229                                          "This can be specified as \"ident_file\" in \"%s\", "
3230                                          "or by the -D invocation option, or by the "
3231                                          "PGDATA environment variable.\n",
3232                                          progname, ConfigFileName);
3233                 return false;
3234         }
3235         SetConfigOption("ident_file", fname, PGC_POSTMASTER, PGC_S_OVERRIDE);
3236         free(fname);
3237
3238         free(configdir);
3239
3240         return true;
3241 }
3242
3243
3244 /*
3245  * Reset all options to their saved default values (implements RESET ALL)
3246  */
3247 void
3248 ResetAllOptions(void)
3249 {
3250         int                     i;
3251
3252         for (i = 0; i < num_guc_variables; i++)
3253         {
3254                 struct config_generic *gconf = guc_variables[i];
3255
3256                 /* Don't reset non-SET-able values */
3257                 if (gconf->context != PGC_SUSET &&
3258                         gconf->context != PGC_USERSET)
3259                         continue;
3260                 /* Don't reset if special exclusion from RESET ALL */
3261                 if (gconf->flags & GUC_NO_RESET_ALL)
3262                         continue;
3263                 /* No need to reset if wasn't SET */
3264                 if (gconf->source <= PGC_S_OVERRIDE)
3265                         continue;
3266
3267                 /* Save old value to support transaction abort */
3268                 push_old_value(gconf);
3269
3270                 switch (gconf->vartype)
3271                 {
3272                         case PGC_BOOL:
3273                                 {
3274                                         struct config_bool *conf = (struct config_bool *) gconf;
3275
3276                                         if (conf->assign_hook)
3277                                                 if (!(*conf->assign_hook) (conf->reset_val, true,
3278                                                                                                    PGC_S_SESSION))
3279                                                         elog(ERROR, "failed to reset %s", conf->gen.name);
3280                                         *conf->variable = conf->reset_val;
3281                                         conf->tentative_val = conf->reset_val;
3282                                         conf->gen.source = conf->gen.reset_source;
3283                                         conf->gen.tentative_source = conf->gen.reset_source;
3284                                         conf->gen.status |= GUC_HAVE_TENTATIVE;
3285                                         guc_dirty = true;
3286                                         break;
3287                                 }
3288                         case PGC_INT:
3289                                 {
3290                                         struct config_int *conf = (struct config_int *) gconf;
3291
3292                                         if (conf->assign_hook)
3293                                                 if (!(*conf->assign_hook) (conf->reset_val, true,
3294                                                                                                    PGC_S_SESSION))
3295                                                         elog(ERROR, "failed to reset %s", conf->gen.name);
3296                                         *conf->variable = conf->reset_val;
3297                                         conf->tentative_val = conf->reset_val;
3298                                         conf->gen.source = conf->gen.reset_source;
3299                                         conf->gen.tentative_source = conf->gen.reset_source;
3300                                         conf->gen.status |= GUC_HAVE_TENTATIVE;
3301                                         guc_dirty = true;
3302                                         break;
3303                                 }
3304                         case PGC_REAL:
3305                                 {
3306                                         struct config_real *conf = (struct config_real *) gconf;
3307
3308                                         if (conf->assign_hook)
3309                                                 if (!(*conf->assign_hook) (conf->reset_val, true,
3310                                                                                                    PGC_S_SESSION))
3311                                                         elog(ERROR, "failed to reset %s", conf->gen.name);
3312                                         *conf->variable = conf->reset_val;
3313                                         conf->tentative_val = conf->reset_val;
3314                                         conf->gen.source = conf->gen.reset_source;
3315                                         conf->gen.tentative_source = conf->gen.reset_source;
3316                                         conf->gen.status |= GUC_HAVE_TENTATIVE;
3317                                         guc_dirty = true;
3318                                         break;
3319                                 }
3320                         case PGC_STRING:
3321                                 {
3322                                         struct config_string *conf = (struct config_string *) gconf;
3323                                         char       *str;
3324
3325                                         if (conf->reset_val == NULL)
3326                                         {
3327                                                 /* Nothing to reset to, as yet; so do nothing */
3328                                                 break;
3329                                         }
3330
3331                                         /* We need not strdup here */
3332                                         str = conf->reset_val;
3333
3334                                         if (conf->assign_hook)
3335                                         {
3336                                                 const char *newstr;
3337
3338                                                 newstr = (*conf->assign_hook) (str, true,
3339                                                                                                            PGC_S_SESSION);
3340                                                 if (newstr == NULL)
3341                                                         elog(ERROR, "failed to reset %s", conf->gen.name);
3342                                                 else if (newstr != str)
3343                                                 {
3344                                                         /*
3345                                                          * See notes in set_config_option about casting
3346                                                          */
3347                                                         str = (char *) newstr;
3348                                                 }
3349                                         }
3350
3351                                         set_string_field(conf, conf->variable, str);
3352                                         set_string_field(conf, &conf->tentative_val, str);
3353                                         conf->gen.source = conf->gen.reset_source;
3354                                         conf->gen.tentative_source = conf->gen.reset_source;
3355                                         conf->gen.status |= GUC_HAVE_TENTATIVE;
3356                                         guc_dirty = true;
3357                                         break;
3358                                 }
3359                 }
3360
3361                 if (gconf->flags & GUC_REPORT)
3362                         ReportGUCOption(gconf);
3363         }
3364 }
3365
3366
3367 /*
3368  * push_old_value
3369  *              Push previous state during first assignment to a GUC variable
3370  *              within a particular transaction.
3371  *
3372  * We have to be willing to "back-fill" the state stack if the first
3373  * assignment occurs within a subtransaction nested several levels deep.
3374  * This ensures that if an intermediate transaction aborts, it will have
3375  * the proper value available to restore the setting to.
3376  */
3377 static void
3378 push_old_value(struct config_generic * gconf)
3379 {
3380         int                     my_level = GetCurrentTransactionNestLevel();
3381         GucStack   *stack;
3382
3383         /* If we're not inside a transaction, do nothing */
3384         if (my_level == 0)
3385                 return;
3386
3387         for (;;)
3388         {
3389                 /* Done if we already pushed it at this nesting depth */
3390                 if (gconf->stack && gconf->stack->nest_level >= my_level)
3391                         return;
3392
3393                 /*
3394                  * We keep all the stack entries in TopTransactionContext so as to
3395                  * avoid allocation problems when a subtransaction back-fills stack
3396                  * entries for upper transaction levels.
3397                  */
3398                 stack = (GucStack *) MemoryContextAlloc(TopTransactionContext,
3399                                                                                                 sizeof(GucStack));
3400
3401                 stack->prev = gconf->stack;
3402                 stack->nest_level = stack->prev ? stack->prev->nest_level + 1 : 1;
3403                 stack->status = gconf->status;
3404                 stack->tentative_source = gconf->tentative_source;
3405                 stack->source = gconf->source;
3406
3407                 switch (gconf->vartype)
3408                 {
3409                         case PGC_BOOL:
3410                                 stack->tentative_val.boolval =
3411                                         ((struct config_bool *) gconf)->tentative_val;
3412                                 stack->value.boolval =
3413                                         *((struct config_bool *) gconf)->variable;
3414                                 break;
3415
3416                         case PGC_INT:
3417                                 stack->tentative_val.intval =
3418                                         ((struct config_int *) gconf)->tentative_val;
3419                                 stack->value.intval =
3420                                         *((struct config_int *) gconf)->variable;
3421                                 break;
3422
3423                         case PGC_REAL:
3424                                 stack->tentative_val.realval =
3425                                         ((struct config_real *) gconf)->tentative_val;
3426                                 stack->value.realval =
3427                                         *((struct config_real *) gconf)->variable;
3428                                 break;
3429
3430                         case PGC_STRING:
3431                                 stack->tentative_val.stringval =
3432                                         ((struct config_string *) gconf)->tentative_val;
3433                                 stack->value.stringval =
3434                                         *((struct config_string *) gconf)->variable;
3435                                 break;
3436                 }
3437
3438                 gconf->stack = stack;
3439
3440                 /* Set state to indicate nothing happened yet within this level */
3441                 gconf->status = GUC_HAVE_STACK;
3442
3443                 /* Ensure we remember to pop at end of xact */
3444                 guc_dirty = true;
3445         }
3446 }
3447
3448 /*
3449  * Do GUC processing at transaction or subtransaction commit or abort.
3450  */
3451 void
3452 AtEOXact_GUC(bool isCommit, bool isSubXact)
3453 {
3454         int                     my_level;
3455         int                     i;
3456
3457         /* Quick exit if nothing's changed in this transaction */
3458         if (!guc_dirty)
3459                 return;
3460
3461         my_level = GetCurrentTransactionNestLevel();
3462         Assert(isSubXact ? (my_level > 1) : (my_level == 1));
3463
3464         for (i = 0; i < num_guc_variables; i++)
3465         {
3466                 struct config_generic *gconf = guc_variables[i];
3467                 int                     my_status = gconf->status;
3468                 GucStack   *stack = gconf->stack;
3469                 bool            useTentative;
3470                 bool            changed;
3471
3472                 /*
3473                  * Skip if nothing's happened to this var in this transaction
3474                  */
3475                 if (my_status == 0)
3476                 {
3477                         Assert(stack == NULL);
3478                         continue;
3479                 }
3480                 /* Assert that we stacked old value before changing it */
3481                 Assert(stack != NULL && (my_status & GUC_HAVE_STACK));
3482                 /* However, the last change may have been at an outer xact level */
3483                 if (stack->nest_level < my_level)
3484                         continue;
3485                 Assert(stack->nest_level == my_level);
3486
3487                 /*
3488                  * We will pop the stack entry.  Start by restoring outer xact status
3489                  * (since we may want to modify it below).      Be careful to use
3490                  * my_status to reference the inner xact status below this point...
3491                  */
3492                 gconf->status = stack->status;
3493
3494                 /*
3495                  * We have two cases:
3496                  *
3497                  * If commit and HAVE_TENTATIVE, set actual value to tentative (this
3498                  * is to override a SET LOCAL if one occurred later than SET). We keep
3499                  * the tentative value and propagate HAVE_TENTATIVE to the parent
3500                  * status, allowing the SET's effect to percolate up. (But if we're
3501                  * exiting the outermost transaction, we'll drop the HAVE_TENTATIVE
3502                  * bit below.)
3503                  *
3504                  * Otherwise, we have a transaction that aborted or executed only SET
3505                  * LOCAL (or no SET at all).  In either case it should have no further
3506                  * effect, so restore both tentative and actual values from the stack
3507                  * entry.
3508                  */
3509
3510                 useTentative = isCommit && (my_status & GUC_HAVE_TENTATIVE) != 0;
3511                 changed = false;
3512
3513                 switch (gconf->vartype)
3514                 {
3515                         case PGC_BOOL:
3516                                 {
3517                                         struct config_bool *conf = (struct config_bool *) gconf;
3518                                         bool            newval;
3519                                         GucSource       newsource;
3520
3521                                         if (useTentative)
3522                                         {
3523                                                 newval = conf->tentative_val;
3524                                                 newsource = conf->gen.tentative_source;
3525                                                 conf->gen.status |= GUC_HAVE_TENTATIVE;
3526                                         }
3527                                         else
3528                                         {
3529                                                 newval = stack->value.boolval;
3530                                                 newsource = stack->source;
3531                                                 conf->tentative_val = stack->tentative_val.boolval;
3532                                                 conf->gen.tentative_source = stack->tentative_source;
3533                                         }
3534
3535                                         if (*conf->variable != newval)
3536                                         {
3537                                                 if (conf->assign_hook)
3538                                                         if (!(*conf->assign_hook) (newval,
3539                                                                                                            true, PGC_S_OVERRIDE))
3540                                                                 elog(LOG, "failed to commit %s",
3541                                                                          conf->gen.name);
3542                                                 *conf->variable = newval;
3543                                                 changed = true;
3544                                         }
3545                                         conf->gen.source = newsource;
3546                                         break;
3547                                 }
3548                         case PGC_INT:
3549                                 {
3550                                         struct config_int *conf = (struct config_int *) gconf;
3551                                         int                     newval;
3552                                         GucSource       newsource;
3553
3554                                         if (useTentative)
3555                                         {
3556                                                 newval = conf->tentative_val;
3557                                                 newsource = conf->gen.tentative_source;
3558                                                 conf->gen.status |= GUC_HAVE_TENTATIVE;
3559                                         }
3560                                         else
3561                                         {
3562                                                 newval = stack->value.intval;
3563                                                 newsource = stack->source;
3564                                                 conf->tentative_val = stack->tentative_val.intval;
3565                                                 conf->gen.tentative_source = stack->tentative_source;
3566                                         }
3567
3568                                         if (*conf->variable != newval)
3569                                         {
3570                                                 if (conf->assign_hook)
3571                                                         if (!(*conf->assign_hook) (newval,
3572                                                                                                            true, PGC_S_OVERRIDE))
3573                                                                 elog(LOG, "failed to commit %s",
3574                                                                          conf->gen.name);
3575                                                 *conf->variable = newval;
3576                                                 changed = true;
3577                                         }
3578                                         conf->gen.source = newsource;
3579                                         break;
3580                                 }
3581                         case PGC_REAL:
3582                                 {
3583                                         struct config_real *conf = (struct config_real *) gconf;
3584                                         double          newval;
3585                                         GucSource       newsource;
3586
3587                                         if (useTentative)
3588                                         {
3589                                                 newval = conf->tentative_val;
3590                                                 newsource = conf->gen.tentative_source;
3591                                                 conf->gen.status |= GUC_HAVE_TENTATIVE;
3592                                         }
3593                                         else
3594                                         {
3595                                                 newval = stack->value.realval;
3596                                                 newsource = stack->source;
3597                                                 conf->tentative_val = stack->tentative_val.realval;
3598                                                 conf->gen.tentative_source = stack->tentative_source;
3599                                         }
3600
3601                                         if (*conf->variable != newval)
3602                                         {
3603                                                 if (conf->assign_hook)
3604                                                         if (!(*conf->assign_hook) (newval,
3605                                                                                                            true, PGC_S_OVERRIDE))
3606                                                                 elog(LOG, "failed to commit %s",
3607                                                                          conf->gen.name);
3608                                                 *conf->variable = newval;
3609                                                 changed = true;
3610                                         }
3611                                         conf->gen.source = newsource;
3612                                         break;
3613                                 }
3614                         case PGC_STRING:
3615                                 {
3616                                         struct config_string *conf = (struct config_string *) gconf;
3617                                         char       *newval;
3618                                         GucSource       newsource;
3619
3620                                         if (useTentative)
3621                                         {
3622                                                 newval = conf->tentative_val;
3623                                                 newsource = conf->gen.tentative_source;
3624                                                 conf->gen.status |= GUC_HAVE_TENTATIVE;
3625                                         }
3626                                         else
3627                                         {
3628                                                 newval = stack->value.stringval;
3629                                                 newsource = stack->source;
3630                                                 set_string_field(conf, &conf->tentative_val,
3631                                                                                  stack->tentative_val.stringval);
3632                                                 conf->gen.tentative_source = stack->tentative_source;
3633                                         }
3634
3635                                         if (*conf->variable != newval)
3636                                         {
3637                                                 if (conf->assign_hook)
3638                                                 {
3639                                                         const char *newstr;
3640
3641                                                         newstr = (*conf->assign_hook) (newval, true,
3642                                                                                                                    PGC_S_OVERRIDE);
3643                                                         if (newstr == NULL)
3644                                                                 elog(LOG, "failed to commit %s",
3645                                                                          conf->gen.name);
3646                                                         else if (newstr != newval)
3647                                                         {
3648                                                                 /*
3649                                                                  * If newval should now be freed, it'll be
3650                                                                  * taken care of below.
3651                                                                  *
3652                                                                  * See notes in set_config_option about
3653                                                                  * casting
3654                                                                  */
3655                                                                 newval = (char *) newstr;
3656                                                         }
3657                                                 }
3658
3659                                                 set_string_field(conf, conf->variable, newval);
3660                                                 changed = true;
3661                                         }
3662                                         conf->gen.source = newsource;
3663                                         /* Release stacked values if not used anymore */
3664                                         set_string_field(conf, &stack->value.stringval,
3665                                                                          NULL);
3666                                         set_string_field(conf, &stack->tentative_val.stringval,
3667                                                                          NULL);
3668                                         /* Don't store tentative value separately after commit */
3669                                         if (!isSubXact)
3670                                                 set_string_field(conf, &conf->tentative_val, NULL);
3671                                         break;
3672                                 }
3673                 }
3674
3675                 /* Finish popping the state stack */
3676                 gconf->stack = stack->prev;
3677                 pfree(stack);
3678
3679                 /*
3680                  * If we're now out of all xact levels, forget TENTATIVE status bit;
3681                  * there's nothing tentative about the value anymore.
3682                  */
3683                 if (!isSubXact)
3684                 {
3685                         Assert(gconf->stack == NULL);
3686                         gconf->status = 0;
3687                 }
3688
3689                 /* Report new value if we changed it */
3690                 if (changed && (gconf->flags & GUC_REPORT))
3691                         ReportGUCOption(gconf);
3692         }
3693
3694         /*
3695          * If we're now out of all xact levels, we can clear guc_dirty. (Note: we
3696          * cannot reset guc_dirty when exiting a subtransaction, because we know
3697          * that all outer transaction levels will have stacked values to deal
3698          * with.)
3699          */
3700         if (!isSubXact)
3701                 guc_dirty = false;
3702 }
3703
3704
3705 /*
3706  * Start up automatic reporting of changes to variables marked GUC_REPORT.
3707  * This is executed at completion of backend startup.
3708  */
3709 void
3710 BeginReportingGUCOptions(void)
3711 {
3712         int                     i;
3713
3714         /*
3715          * Don't do anything unless talking to an interactive frontend of protocol
3716          * 3.0 or later.
3717          */
3718         if (whereToSendOutput != DestRemote ||
3719                 PG_PROTOCOL_MAJOR(FrontendProtocol) < 3)
3720                 return;
3721
3722         reporting_enabled = true;
3723
3724         /* Transmit initial values of interesting variables */
3725         for (i = 0; i < num_guc_variables; i++)
3726         {
3727                 struct config_generic *conf = guc_variables[i];
3728
3729                 if (conf->flags & GUC_REPORT)
3730                         ReportGUCOption(conf);
3731         }
3732 }
3733
3734 /*
3735  * ReportGUCOption: if appropriate, transmit option value to frontend
3736  */
3737 static void
3738 ReportGUCOption(struct config_generic * record)
3739 {
3740         if (reporting_enabled && (record->flags & GUC_REPORT))
3741         {
3742                 char       *val = _ShowOption(record, false);
3743                 StringInfoData msgbuf;
3744
3745                 pq_beginmessage(&msgbuf, 'S');
3746                 pq_sendstring(&msgbuf, record->name);
3747                 pq_sendstring(&msgbuf, val);
3748                 pq_endmessage(&msgbuf);
3749
3750                 pfree(val);
3751         }
3752 }
3753
3754
3755 /*
3756  * Try to interpret value as boolean value.  Valid values are: true,
3757  * false, yes, no, on, off, 1, 0; as well as unique prefixes thereof.
3758  * If the string parses okay, return true, else false.
3759  * If okay and result is not NULL, return the value in *result.
3760  */
3761 static bool
3762 parse_bool(const char *value, bool *result)
3763 {
3764         size_t          len = strlen(value);
3765
3766         if (pg_strncasecmp(value, "true", len) == 0)
3767         {
3768                 if (result)
3769                         *result = true;
3770         }
3771         else if (pg_strncasecmp(value, "false", len) == 0)
3772         {
3773                 if (result)
3774                         *result = false;
3775         }
3776
3777         else if (pg_strncasecmp(value, "yes", len) == 0)
3778         {
3779                 if (result)
3780                         *result = true;
3781         }
3782         else if (pg_strncasecmp(value, "no", len) == 0)
3783         {
3784                 if (result)
3785                         *result = false;
3786         }
3787
3788         /* 'o' is not unique enough */
3789         else if (pg_strncasecmp(value, "on", (len > 2 ? len : 2)) == 0)
3790         {
3791                 if (result)
3792                         *result = true;
3793         }
3794         else if (pg_strncasecmp(value, "off", (len > 2 ? len : 2)) == 0)
3795         {
3796                 if (result)
3797                         *result = false;
3798         }
3799
3800         else if (pg_strcasecmp(value, "1") == 0)
3801         {
3802                 if (result)
3803                         *result = true;
3804         }
3805         else if (pg_strcasecmp(value, "0") == 0)
3806         {
3807                 if (result)
3808                         *result = false;
3809         }
3810
3811         else
3812         {
3813                 if (result)
3814                         *result = false;        /* suppress compiler warning */
3815                 return false;
3816         }
3817         return true;
3818 }
3819
3820
3821
3822 /*
3823  * Try to parse value as an integer.  The accepted formats are the
3824  * usual decimal, octal, or hexadecimal formats, optionally followed by
3825  * a unit name if "flags" indicates a unit is allowed.
3826  *
3827  * If the string parses okay, return true, else false.
3828  * If okay and result is not NULL, return the value in *result.
3829  * If not okay and hintmsg is not NULL, *hintmsg is set to a suitable
3830  *      HINT message, or NULL if no hint provided.
3831  */
3832 static bool
3833 parse_int(const char *value, int *result, int flags, const char **hintmsg)
3834 {
3835         int64           val;
3836         char       *endptr;
3837
3838         /* To suppress compiler warnings, always set output params */
3839         if (result)
3840                 *result = 0;
3841         if (hintmsg)
3842                 *hintmsg = NULL;
3843
3844         /* We assume here that int64 is at least as wide as long */
3845         errno = 0;
3846         val = strtol(value, &endptr, 0);
3847
3848         if (endptr == value)
3849                 return false;                   /* no HINT for integer syntax error */
3850
3851         if (errno == ERANGE || val != (int64) ((int32) val))
3852         {
3853                 if (hintmsg)
3854                         *hintmsg = gettext_noop("Value exceeds integer range.");
3855                 return false;
3856         }
3857
3858         /* allow whitespace between integer and unit */
3859         while (isspace((unsigned char) *endptr))
3860                 endptr++;
3861
3862         /* Handle possible unit */
3863         if (*endptr != '\0')
3864         {
3865                 /*
3866                  * Note: the multiple-switch coding technique here is a bit tedious,
3867                  * but seems necessary to avoid intermediate-value overflows.
3868                  *
3869                  * If INT64_IS_BUSTED (ie, it's really int32) we will fail to detect
3870                  * overflow due to units conversion, but there are few enough such
3871                  * machines that it does not seem worth trying to be smarter.
3872                  */
3873                 if (flags & GUC_UNIT_MEMORY)
3874                 {
3875                         /* Set hint for use if no match or trailing garbage */
3876                         if (hintmsg)
3877                                 *hintmsg = gettext_noop("Valid units for this parameter are \"kB\", \"MB\", and \"GB\".");
3878
3879 #if BLCKSZ < 1024 || BLCKSZ > (1024*1024)
3880 #error BLCKSZ must be between 1KB and 1MB
3881 #endif
3882 #if XLOG_BLCKSZ < 1024 || XLOG_BLCKSZ > (1024*1024)
3883 #error XLOG_BLCKSZ must be between 1KB and 1MB
3884 #endif
3885
3886                         if (strncmp(endptr, "kB", 2) == 0)
3887                         {
3888                                 endptr += 2;
3889                                 switch (flags & GUC_UNIT_MEMORY)
3890                                 {
3891                                         case GUC_UNIT_BLOCKS:
3892                                                 val /= (BLCKSZ / 1024);
3893                                                 break;
3894                                         case GUC_UNIT_XBLOCKS:
3895                                                 val /= (XLOG_BLCKSZ / 1024);
3896                                                 break;
3897                                 }
3898                         }
3899                         else if (strncmp(endptr, "MB", 2) == 0)
3900                         {
3901                                 endptr += 2;
3902                                 switch (flags & GUC_UNIT_MEMORY)
3903                                 {
3904                                         case GUC_UNIT_KB:
3905                                                 val *= KB_PER_MB;
3906                                                 break;
3907                                         case GUC_UNIT_BLOCKS:
3908                                                 val *= KB_PER_MB / (BLCKSZ / 1024);
3909                                                 break;
3910                                         case GUC_UNIT_XBLOCKS:
3911                                                 val *= KB_PER_MB / (XLOG_BLCKSZ / 1024);
3912                                                 break;
3913                                 }
3914                         }
3915                         else if (strncmp(endptr, "GB", 2) == 0)
3916                         {
3917                                 endptr += 2;
3918                                 switch (flags & GUC_UNIT_MEMORY)
3919                                 {
3920                                         case GUC_UNIT_KB:
3921                                                 val *= KB_PER_GB;
3922                                                 break;
3923                                         case GUC_UNIT_BLOCKS:
3924                                                 val *= KB_PER_GB / (BLCKSZ / 1024);
3925                                                 break;
3926                                         case GUC_UNIT_XBLOCKS:
3927                                                 val *= KB_PER_GB / (XLOG_BLCKSZ / 1024);
3928                                                 break;
3929                                 }
3930                         }
3931                 }
3932                 else if (flags & GUC_UNIT_TIME)
3933                 {
3934                         /* Set hint for use if no match or trailing garbage */
3935                         if (hintmsg)
3936                                 *hintmsg = gettext_noop("Valid units for this parameter are \"ms\", \"s\", \"min\", \"h\", and \"d\".");
3937
3938                         if (strncmp(endptr, "ms", 2) == 0)
3939                         {
3940                                 endptr += 2;
3941                                 switch (flags & GUC_UNIT_TIME)
3942                                 {
3943                                         case GUC_UNIT_S:
3944                                                 val /= MS_PER_S;
3945                                                 break;
3946                                         case GUC_UNIT_MIN:
3947                                                 val /= MS_PER_MIN;
3948                                                 break;
3949                                 }
3950                         }
3951                         else if (strncmp(endptr, "s", 1) == 0)
3952                         {
3953                                 endptr += 1;
3954                                 switch (flags & GUC_UNIT_TIME)
3955                                 {
3956                                         case GUC_UNIT_MS:
3957                                                 val *= MS_PER_S;
3958                                                 break;
3959                                         case GUC_UNIT_MIN:
3960                                                 val /= S_PER_MIN;
3961                                                 break;
3962                                 }
3963                         }
3964                         else if (strncmp(endptr, "min", 3) == 0)
3965                         {
3966                                 endptr += 3;
3967                                 switch (flags & GUC_UNIT_TIME)
3968                                 {
3969                                         case GUC_UNIT_MS:
3970                                                 val *= MS_PER_MIN;
3971                                                 break;
3972                                         case GUC_UNIT_S:
3973                                                 val *= S_PER_MIN;
3974                                                 break;
3975                                 }
3976                         }
3977                         else if (strncmp(endptr, "h", 1) == 0)
3978                         {
3979                                 endptr += 1;
3980                                 switch (flags & GUC_UNIT_TIME)
3981                                 {
3982                                         case GUC_UNIT_MS:
3983                                                 val *= MS_PER_H;
3984                                                 break;
3985                                         case GUC_UNIT_S:
3986                                                 val *= S_PER_H;
3987                                                 break;
3988                                         case GUC_UNIT_MIN:
3989                                                 val *= MIN_PER_H;
3990                                                 break;
3991                                 }
3992                         }
3993                         else if (strncmp(endptr, "d", 1) == 0)
3994                         {
3995                                 endptr += 1;
3996                                 switch (flags & GUC_UNIT_TIME)
3997                                 {
3998                                         case GUC_UNIT_MS:
3999                                                 val *= MS_PER_D;
4000                                                 break;
4001                                         case GUC_UNIT_S:
4002                                                 val *= S_PER_D;
4003                                                 break;
4004                                         case GUC_UNIT_MIN:
4005                                                 val *= MIN_PER_D;
4006                                                 break;
4007                                 }
4008                         }
4009                 }
4010
4011                 /* allow whitespace after unit */
4012                 while (isspace((unsigned char) *endptr))
4013                         endptr++;
4014
4015                 if (*endptr != '\0')
4016                         return false;           /* appropriate hint, if any, already set */
4017
4018                 /* Check for overflow due to units conversion */
4019                 if (val != (int64) ((int32) val))
4020                 {
4021                         if (hintmsg)
4022                                 *hintmsg = gettext_noop("Value exceeds integer range.");
4023                         return false;
4024                 }
4025         }
4026
4027         if (result)
4028                 *result = (int) val;
4029         return true;
4030 }
4031
4032
4033
4034 /*
4035  * Try to parse value as a floating point number in the usual format.
4036  * If the string parses okay, return true, else false.
4037  * If okay and result is not NULL, return the value in *result.
4038  */
4039 static bool
4040 parse_real(const char *value, double *result)
4041 {
4042         double          val;
4043         char       *endptr;
4044
4045         if (result)
4046                 *result = 0;                    /* suppress compiler warning */
4047
4048         errno = 0;
4049         val = strtod(value, &endptr);
4050         if (endptr == value || errno == ERANGE)
4051                 return false;
4052
4053         /* allow whitespace after number */
4054         while (isspace((unsigned char) *endptr))
4055                 endptr++;
4056         if (*endptr != '\0')
4057                 return false;
4058
4059         if (result)
4060                 *result = val;
4061         return true;
4062 }
4063
4064
4065 /*
4066  * Call a GucStringAssignHook function, being careful to free the
4067  * "newval" string if the hook ereports.
4068  *
4069  * This is split out of set_config_option just to avoid the "volatile"
4070  * qualifiers that would otherwise have to be plastered all over.
4071  */
4072 static const char *
4073 call_string_assign_hook(GucStringAssignHook assign_hook,
4074                                                 char *newval, bool doit, GucSource source)
4075 {
4076         const char *result;
4077
4078         PG_TRY();
4079         {
4080                 result = (*assign_hook) (newval, doit, source);
4081         }
4082         PG_CATCH();
4083         {
4084                 free(newval);
4085                 PG_RE_THROW();
4086         }
4087         PG_END_TRY();
4088
4089         return result;
4090 }
4091
4092
4093 /*
4094  * Sets option `name' to given value. The value should be a string
4095  * which is going to be parsed and converted to the appropriate data
4096  * type.  The context and source parameters indicate in which context this
4097  * function is being called so it can apply the access restrictions
4098  * properly.
4099  *
4100  * If value is NULL, set the option to its default value. If the
4101  * parameter changeVal is false then don't really set the option but do all
4102  * the checks to see if it would work.
4103  *
4104  * If there is an error (non-existing option, invalid value) then an
4105  * ereport(ERROR) is thrown *unless* this is called in a context where we
4106  * don't want to ereport (currently, startup or SIGHUP config file reread).
4107  * In that case we write a suitable error message via ereport(DEBUG) and
4108  * return false. This is working around the deficiencies in the ereport
4109  * mechanism, so don't blame me.  In all other cases, the function
4110  * returns true, including cases where the input is valid but we chose
4111  * not to apply it because of context or source-priority considerations.
4112  *
4113  * See also SetConfigOption for an external interface.
4114  */
4115 bool
4116 set_config_option(const char *name, const char *value,
4117                                   GucContext context, GucSource source,
4118                                   bool isLocal, bool changeVal)
4119 {
4120         struct config_generic *record;
4121         int                     elevel;
4122         bool            makeDefault;
4123
4124         if (context == PGC_SIGHUP || source == PGC_S_DEFAULT)
4125         {
4126                 /*
4127                  * To avoid cluttering the log, only the postmaster bleats loudly
4128                  * about problems with the config file.
4129                  */
4130                 elevel = IsUnderPostmaster ? DEBUG2 : LOG;
4131         }
4132         else if (source == PGC_S_DATABASE || source == PGC_S_USER)
4133                 elevel = INFO;
4134         else
4135                 elevel = ERROR;
4136
4137         record = find_option(name, elevel);
4138         if (record == NULL)
4139         {
4140                 ereport(elevel,
4141                                 (errcode(ERRCODE_UNDEFINED_OBJECT),
4142                            errmsg("unrecognized configuration parameter \"%s\"", name)));
4143                 return false;
4144         }
4145
4146         /*
4147          * Do not replace a value that has been set on the command line by a SIGHUP
4148          * reload
4149          */
4150         if (context == PGC_SIGHUP && record->source == PGC_S_ARGV)
4151                 return true;
4152
4153         /*
4154          * Check if the option can be set at this time. See guc.h for the precise
4155          * rules. Note that we don't want to throw errors if we're in the SIGHUP
4156          * context. In that case we just ignore the attempt and return true.
4157          */
4158         switch (record->context)
4159         {
4160                 case PGC_INTERNAL:
4161                         if (context == PGC_SIGHUP)
4162                                 return true;
4163                         if (context != PGC_INTERNAL)
4164                         {
4165                                 ereport(elevel,
4166                                                 (errcode(ERRCODE_CANT_CHANGE_RUNTIME_PARAM),
4167                                                  errmsg("parameter \"%s\" cannot be changed",
4168                                                                 name)));
4169                                 return false;
4170                         }
4171                         break;
4172                 case PGC_POSTMASTER:
4173                         if (context == PGC_SIGHUP)
4174                         {
4175                                 if (changeVal && !is_newvalue_equal(record, value))
4176                                         ereport(elevel,
4177                                                         (errcode(ERRCODE_CANT_CHANGE_RUNTIME_PARAM),
4178                                                          errmsg("parameter \"%s\" cannot be changed after server start; configuration file change ignored",
4179                                                                         name)));
4180
4181                                 return true;
4182                         }
4183                         if (context != PGC_POSTMASTER)
4184                         {
4185                                 ereport(elevel,
4186                                                 (errcode(ERRCODE_CANT_CHANGE_RUNTIME_PARAM),
4187                                                  errmsg("parameter \"%s\" cannot be changed after server start",
4188                                                                 name)));
4189                                 return false;
4190                         }
4191                         break;
4192                 case PGC_SIGHUP:
4193                         if (context != PGC_SIGHUP && context != PGC_POSTMASTER)
4194                         {
4195                                 ereport(elevel,
4196                                                 (errcode(ERRCODE_CANT_CHANGE_RUNTIME_PARAM),
4197                                                  errmsg("parameter \"%s\" cannot be changed now",
4198                                                                 name)));
4199                                 return false;
4200                         }
4201
4202                         /*
4203                          * Hmm, the idea of the SIGHUP context is "ought to be global, but
4204                          * can be changed after postmaster start". But there's nothing
4205                          * that prevents a crafty administrator from sending SIGHUP
4206                          * signals to individual backends only.
4207                          */
4208                         break;
4209                 case PGC_BACKEND:
4210                         if (context == PGC_SIGHUP)
4211                         {
4212                                 /*
4213                                  * If a PGC_BACKEND parameter is changed in the config file,
4214                                  * we want to accept the new value in the postmaster (whence
4215                                  * it will propagate to subsequently-started backends), but
4216                                  * ignore it in existing backends.      This is a tad klugy, but
4217                                  * necessary because we don't re-read the config file during
4218                                  * backend start.
4219                                  */
4220                                 if (IsUnderPostmaster)
4221                                         return true;
4222                         }
4223                         else if (context != PGC_BACKEND && context != PGC_POSTMASTER)
4224                         {
4225                                 ereport(elevel,
4226                                                 (errcode(ERRCODE_CANT_CHANGE_RUNTIME_PARAM),
4227                                                  errmsg("parameter \"%s\" cannot be set after connection start",
4228                                                                 name)));
4229                                 return false;
4230                         }
4231                         break;
4232                 case PGC_SUSET:
4233                         if (context == PGC_USERSET || context == PGC_BACKEND)
4234                         {
4235                                 ereport(elevel,
4236                                                 (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
4237                                                  errmsg("permission denied to set parameter \"%s\"",
4238                                                                 name)));
4239                                 return false;
4240                         }
4241                         break;
4242                 case PGC_USERSET:
4243                         /* always okay */
4244                         break;
4245         }
4246
4247         /*
4248          * Should we set reset/stacked values?  (If so, the behavior is not
4249          * transactional.)  This is done either when we get a default
4250          * value from the database's/user's/client's default settings or
4251          * when we reset a value to its default.
4252          */
4253         makeDefault = changeVal && (source <= PGC_S_OVERRIDE)
4254                                         && ((value != NULL) || source == PGC_S_DEFAULT);
4255
4256         /*
4257          * Ignore attempted set if overridden by previously processed
4258          * setting.  However, if changeVal is false then plow ahead anyway
4259          * since we are trying to find out if the value is potentially
4260          * good, not actually use it.  Also keep going if makeDefault is
4261          * true, since we may want to set the reset/stacked values even if
4262          * we can't set the variable itself.  There's one exception to
4263          * this rule: if we want to apply the default value to variables
4264          * that were removed from the configuration file.  This is
4265          * indicated by source == PGC_S_DEFAULT and context == PGC_SIGHUP.
4266          */
4267         if (record->source > source
4268                 && !(source == PGC_S_DEFAULT && context == PGC_SIGHUP))
4269         {
4270                 if (changeVal && !makeDefault)
4271                 {
4272                         elog(DEBUG3, "\"%s\": setting ignored because previous source is higher priority",
4273                                  name);
4274                         return true;
4275                 }
4276                 changeVal = false;
4277         }
4278
4279         /*
4280          * Evaluate value and set variable.
4281          */
4282         switch (record->vartype)
4283         {
4284                 case PGC_BOOL:
4285                         {
4286                                 struct config_bool *conf = (struct config_bool *) record;
4287                                 bool            newval;
4288
4289                                 if (value)
4290                                 {
4291                                         if (!parse_bool(value, &newval))
4292                                         {
4293                                                 ereport(elevel,
4294                                                                 (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
4295                                                   errmsg("parameter \"%s\" requires a Boolean value",
4296                                                                  name)));
4297                                                 return false;
4298                                         }
4299                                 }
4300                                 /*
4301                                  * If value == NULL and source == PGC_S_DEFAULT then
4302                                  * we reset some value to its default (removed from
4303                                  * configuration file).
4304                                  */
4305                                 else if (source == PGC_S_DEFAULT)
4306                                         newval = conf->boot_val;
4307                                 /* else we handle a "RESET varname" command */
4308                                 else
4309                                 {
4310                                         newval = conf->reset_val;
4311                                         source = conf->gen.reset_source;
4312                                 }
4313
4314                                 if (conf->assign_hook)
4315                                         if (!(*conf->assign_hook) (newval, changeVal, source))
4316                                         {
4317                                                 ereport(elevel,
4318                                                                 (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
4319                                                          errmsg("invalid value for parameter \"%s\": %d",
4320                                                                         name, (int) newval)));
4321                                                 return false;
4322                                         }
4323
4324                                 if (changeVal || makeDefault)
4325                                 {
4326                                         /* Save old value to support transaction abort */
4327                                         if (!makeDefault)
4328                                                 push_old_value(&conf->gen);
4329                                         if (changeVal)
4330                                         {
4331                                                 *conf->variable = newval;
4332                                                 conf->gen.source = source;
4333                                         }
4334                                         if (makeDefault)
4335                                         {
4336                                                 GucStack   *stack;
4337
4338                                                 if (conf->gen.reset_source <= source)
4339                                                 {
4340                                                         conf->reset_val = newval;
4341                                                         conf->gen.reset_source = source;
4342                                                 }
4343                                                 for (stack = conf->gen.stack; stack; stack = stack->prev)
4344                                                 {
4345                                                         if (stack->source <= source)
4346                                                         {
4347                                                                 stack->value.boolval = newval;
4348                                                                 stack->source = source;
4349                                                         }
4350                                                 }
4351                                         }
4352                                         else if (isLocal)
4353                                         {
4354                                                 conf->gen.status |= GUC_HAVE_LOCAL;
4355                                                 guc_dirty = true;
4356                                         }
4357                                         else
4358                                         {
4359                                                 conf->tentative_val = newval;
4360                                                 conf->gen.tentative_source = source;
4361                                                 conf->gen.status |= GUC_HAVE_TENTATIVE;
4362                                                 guc_dirty = true;
4363                                         }
4364                                 }
4365                                 break;
4366                         }
4367
4368                 case PGC_INT:
4369                         {
4370                                 struct config_int *conf = (struct config_int *) record;
4371                                 int                     newval;
4372
4373                                 if (value)
4374                                 {
4375                                         const char *hintmsg;
4376
4377                                         if (!parse_int(value, &newval, conf->gen.flags, &hintmsg))
4378                                         {
4379                                                 ereport(elevel,
4380                                                                 (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
4381                                                                  errmsg("invalid value for parameter \"%s\": \"%s\"",
4382                                                                                 name, value),
4383                                                                  hintmsg ? errhint(hintmsg) : 0));
4384                                                 return false;
4385                                         }
4386                                         if (newval < conf->min || newval > conf->max)
4387                                         {
4388                                                 ereport(elevel,
4389                                                                 (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
4390                                                                  errmsg("%d is outside the valid range for parameter \"%s\" (%d .. %d)",
4391                                                                                 newval, name, conf->min, conf->max)));
4392                                                 return false;
4393                                         }
4394                                 }
4395                                 /*
4396                                  * If value == NULL and source == PGC_S_DEFAULT then
4397                                  * we reset some value to its default (removed from
4398                                  * configuration file).
4399                                  */
4400                                 else if (source == PGC_S_DEFAULT)
4401                                         newval = conf->boot_val;
4402                                 /* else we handle a "RESET varname" command */
4403                                 else
4404                                 {
4405                                         newval = conf->reset_val;
4406                                         source = conf->gen.reset_source;
4407                                 }
4408
4409                                 if (conf->assign_hook)
4410                                         if (!(*conf->assign_hook) (newval, changeVal, source))
4411                                         {
4412                                                 ereport(elevel,
4413                                                                 (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
4414                                                          errmsg("invalid value for parameter \"%s\": %d",
4415                                                                         name, newval)));
4416                                                 return false;
4417                                         }
4418
4419                                 if (changeVal || makeDefault)
4420                                 {
4421                                         /* Save old value to support transaction abort */
4422                                         if (!makeDefault)
4423                                                 push_old_value(&conf->gen);
4424                                         if (changeVal)
4425                                         {
4426                                                 *conf->variable = newval;
4427                                                 conf->gen.source = source;
4428                                         }
4429                                         if (makeDefault)
4430                                         {
4431                                                 GucStack   *stack;
4432
4433                                                 if (conf->gen.reset_source <= source)
4434                                                 {
4435                                                         conf->reset_val = newval;
4436                                                         conf->gen.reset_source = source;
4437                                                 }
4438                                                 for (stack = conf->gen.stack; stack; stack = stack->prev)
4439                                                 {
4440                                                         if (stack->source <= source)
4441                                                         {
4442                                                                 stack->value.intval = newval;
4443                                                                 stack->source = source;
4444                                                         }
4445                                                 }
4446                                         }
4447                                         else if (isLocal)
4448                                         {
4449                                                 conf->gen.status |= GUC_HAVE_LOCAL;
4450                                                 guc_dirty = true;
4451                                         }
4452                                         else
4453                                         {
4454                                                 conf->tentative_val = newval;
4455                                                 conf->gen.tentative_source = source;
4456                                                 conf->gen.status |= GUC_HAVE_TENTATIVE;
4457                                                 guc_dirty = true;
4458                                         }
4459                                 }
4460                                 break;
4461                         }
4462
4463                 case PGC_REAL:
4464                         {
4465                                 struct config_real *conf = (struct config_real *) record;
4466                                 double          newval;
4467
4468                                 if (value)
4469                                 {
4470                                         if (!parse_real(value, &newval))
4471                                         {
4472                                                 ereport(elevel,
4473                                                                 (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
4474                                                   errmsg("parameter \"%s\" requires a numeric value",
4475                                                                  name)));
4476                                                 return false;
4477                                         }
4478                                         if (newval < conf->min || newval > conf->max)
4479                                         {
4480                                                 ereport(elevel,
4481                                                                 (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
4482                                                                  errmsg("%g is outside the valid range for parameter \"%s\" (%g .. %g)",
4483                                                                                 newval, name, conf->min, conf->max)));
4484                                                 return false;
4485                                         }
4486                                 }
4487                                 /*
4488                                  * If value == NULL and source == PGC_S_DEFAULT then
4489                                  * we reset some value to its default (removed from
4490                                  * configuration file).
4491                                  */
4492                                 else if (source == PGC_S_DEFAULT)
4493                                         newval = conf->boot_val;
4494                                 /* else we handle a "RESET varname" command */
4495                                 else
4496                                 {
4497                                         newval = conf->reset_val;
4498                                         source = conf->gen.reset_source;
4499                                 }
4500
4501                                 if (conf->assign_hook)
4502                                         if (!(*conf->assign_hook) (newval, changeVal, source))
4503                                         {
4504                                                 ereport(elevel,
4505                                                                 (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
4506                                                          errmsg("invalid value for parameter \"%s\": %g",
4507                                                                         name, newval)));
4508                                                 return false;
4509                                         }
4510
4511                                 if (changeVal || makeDefault)
4512                                 {
4513                                         /* Save old value to support transaction abort */
4514                                         if (!makeDefault)
4515                                                 push_old_value(&conf->gen);
4516                                         if (changeVal)
4517                                         {
4518                                                 *conf->variable = newval;
4519                                                 conf->gen.source = source;
4520                                         }
4521                                         if (makeDefault)
4522                                         {
4523                                                 GucStack   *stack;
4524
4525                                                 if (conf->gen.reset_source <= source)
4526                                                 {
4527                                                         conf->reset_val = newval;
4528                                                         conf->gen.reset_source = source;
4529                                                 }
4530                                                 for (stack = conf->gen.stack; stack; stack = stack->prev)
4531                                                 {
4532                                                         if (stack->source <= source)
4533                                                         {
4534                                                                 stack->value.realval = newval;
4535                                                                 stack->source = source;
4536                                                         }
4537                                                 }
4538                                         }
4539                                         else if (isLocal)
4540                                         {
4541                                                 conf->gen.status |= GUC_HAVE_LOCAL;
4542                                                 guc_dirty = true;
4543                                         }
4544                                         else
4545                                         {
4546                                                 conf->tentative_val = newval;
4547                                                 conf->gen.tentative_source = source;
4548                                                 conf->gen.status |= GUC_HAVE_TENTATIVE;
4549                                                 guc_dirty = true;
4550                                         }
4551                                 }
4552                                 break;
4553                         }
4554
4555                 case PGC_STRING:
4556                         {
4557                                 struct config_string *conf = (struct config_string *) record;
4558                                 char       *newval;
4559
4560                                 if (value)
4561                                 {
4562                                         newval = guc_strdup(elevel, value);
4563                                         if (newval == NULL)
4564                                                 return false;
4565
4566                                         /*
4567                                          * The only sort of "parsing" check we need to do is apply
4568                                          * truncation if GUC_IS_NAME.
4569                                          */
4570                                         if (conf->gen.flags & GUC_IS_NAME)
4571                                                 truncate_identifier(newval, strlen(newval), true);
4572                                 }
4573                                 /*
4574                                  * If value == NULL and source == PGC_S_DEFAULT then
4575                                  * we reset some value to its default (removed from
4576                                  * configuration file).
4577                                  */
4578                                 else if (source == PGC_S_DEFAULT)
4579                                 {
4580                                         if (conf->boot_val == NULL)
4581                                                 newval = NULL;
4582                                         else
4583                                         {
4584                                                 newval = guc_strdup(elevel, conf->boot_val);
4585                                                 if (newval == NULL)
4586                                                         return false;
4587                                         }
4588                                 }
4589                                 /* else we handle a "RESET varname" command */
4590                                 else if (conf->reset_val)
4591                                 {
4592                                         /*
4593                                          * We could possibly avoid strdup here, but easier to make
4594                                          * this case work the same as the normal assignment case.
4595                                          */
4596                                         newval = guc_strdup(elevel, conf->reset_val);
4597                                         if (newval == NULL)
4598                                                 return false;
4599                                         source = conf->gen.reset_source;
4600                                 }
4601                                 else
4602                                 {
4603                                         /* Nothing to reset to, as yet; so do nothing */
4604                                         break;
4605                                 }
4606
4607                                 if (conf->assign_hook)
4608                                 {
4609                                         const char *hookresult;
4610
4611                                         /*
4612                                          * If the hook ereports, we have to make sure we free
4613                                          * newval, else it will be a permanent memory leak.
4614                                          */
4615                                         hookresult = call_string_assign_hook(conf->assign_hook,
4616                                                                                                                  newval,
4617                                                                                                                  changeVal,
4618                                                                                                                  source);
4619                                         if (hookresult == NULL)
4620                                         {
4621                                                 free(newval);
4622                                                 ereport(elevel,
4623                                                                 (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
4624                                                  errmsg("invalid value for parameter \"%s\": \"%s\"",
4625                                                                 name, value ? value : "")));
4626                                                 return false;
4627                                         }
4628                                         else if (hookresult != newval)
4629                                         {
4630                                                 free(newval);
4631
4632                                                 /*
4633                                                  * Having to cast away const here is annoying, but the
4634                                                  * alternative is to declare assign_hooks as returning
4635                                                  * char*, which would mean they'd have to cast away
4636                                                  * const, or as both taking and returning char*, which
4637                                                  * doesn't seem attractive either --- we don't want
4638                                                  * them to scribble on the passed str.
4639                                                  */
4640                                                 newval = (char *) hookresult;
4641                                         }
4642                                 }
4643
4644                                 if (changeVal || makeDefault)
4645                                 {
4646                                         /* Save old value to support transaction abort */
4647                                         if (!makeDefault)
4648                                                 push_old_value(&conf->gen);
4649                                         if (changeVal)
4650                                         {
4651                                                 set_string_field(conf, conf->variable, newval);
4652                                                 conf->gen.source = source;
4653                                         }
4654                                         if (makeDefault)
4655                                         {
4656                                                 GucStack   *stack;
4657
4658                                                 if (conf->gen.reset_source <= source)
4659                                                 {
4660                                                         set_string_field(conf, &conf->reset_val, newval);
4661                                                         conf->gen.reset_source = source;
4662                                                 }
4663                                                 for (stack = conf->gen.stack; stack; stack = stack->prev)
4664                                                 {
4665                                                         if (stack->source <= source)
4666                                                         {
4667                                                                 set_string_field(conf, &stack->value.stringval,
4668                                                                                                  newval);
4669                                                                 stack->source = source;
4670                                                         }
4671                                                 }
4672                                                 /* Perhaps we didn't install newval anywhere */
4673                                                 if (!string_field_used(conf, newval))
4674                                                         free(newval);
4675                                         }
4676                                         else if (isLocal)
4677                                         {
4678                                                 conf->gen.status |= GUC_HAVE_LOCAL;
4679                                                 guc_dirty = true;
4680                                         }
4681                                         else
4682                                         {
4683                                                 set_string_field(conf, &conf->tentative_val, newval);
4684                                                 conf->gen.tentative_source = source;
4685                                                 conf->gen.status |= GUC_HAVE_TENTATIVE;
4686                                                 guc_dirty = true;
4687                                         }
4688                                 }
4689                                 else
4690                                         free(newval);
4691                                 break;
4692                         }
4693         }
4694
4695         if (changeVal && (record->flags & GUC_REPORT))
4696                 ReportGUCOption(record);
4697
4698         return true;
4699 }
4700
4701
4702 /*
4703  * Set a config option to the given value. See also set_config_option,
4704  * this is just the wrapper to be called from outside GUC.      NB: this
4705  * is used only for non-transactional operations.
4706  */
4707 void
4708 SetConfigOption(const char *name, const char *value,
4709                                 GucContext context, GucSource source)
4710 {
4711         (void) set_config_option(name, value, context, source, false, true);
4712 }
4713
4714
4715
4716 /*
4717  * Fetch the current value of the option `name'. If the option doesn't exist,
4718  * throw an ereport and don't return.
4719  *
4720  * The string is *not* allocated for modification and is really only
4721  * valid until the next call to configuration related functions.
4722  */
4723 const char *
4724 GetConfigOption(const char *name)
4725 {
4726         struct config_generic *record;
4727         static char buffer[256];
4728
4729         record = find_option(name, ERROR);
4730         if (record == NULL)
4731                 ereport(ERROR,
4732                                 (errcode(ERRCODE_UNDEFINED_OBJECT),
4733                            errmsg("unrecognized configuration parameter \"%s\"", name)));
4734         if ((record->flags & GUC_SUPERUSER_ONLY) && !superuser())
4735                 ereport(ERROR,
4736                                 (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
4737                                  errmsg("must be superuser to examine \"%s\"", name)));
4738
4739         switch (record->vartype)
4740         {
4741                 case PGC_BOOL:
4742                         return *((struct config_bool *) record)->variable ? "on" : "off";
4743
4744                 case PGC_INT:
4745                         snprintf(buffer, sizeof(buffer), "%d",
4746                                          *((struct config_int *) record)->variable);
4747                         return buffer;
4748
4749                 case PGC_REAL:
4750                         snprintf(buffer, sizeof(buffer), "%g",
4751                                          *((struct config_real *) record)->variable);
4752                         return buffer;
4753
4754                 case PGC_STRING:
4755                         return *((struct config_string *) record)->variable;
4756         }
4757         return NULL;
4758 }
4759
4760 /*
4761  * Get the RESET value associated with the given option.
4762  */
4763 const char *
4764 GetConfigOptionResetString(const char *name)
4765 {
4766         struct config_generic *record;
4767         static char buffer[256];
4768
4769         record = find_option(name, ERROR);
4770         if (record == NULL)
4771                 ereport(ERROR,
4772                                 (errcode(ERRCODE_UNDEFINED_OBJECT),
4773                            errmsg("unrecognized configuration parameter \"%s\"", name)));
4774         if ((record->flags & GUC_SUPERUSER_ONLY) && !superuser())
4775                 ereport(ERROR,
4776                                 (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
4777                                  errmsg("must be superuser to examine \"%s\"", name)));
4778
4779         switch (record->vartype)
4780         {
4781                 case PGC_BOOL:
4782                         return ((struct config_bool *) record)->reset_val ? "on" : "off";
4783
4784                 case PGC_INT:
4785                         snprintf(buffer, sizeof(buffer), "%d",
4786                                          ((struct config_int *) record)->reset_val);
4787                         return buffer;
4788
4789                 case PGC_REAL:
4790                         snprintf(buffer, sizeof(buffer), "%g",
4791                                          ((struct config_real *) record)->reset_val);
4792                         return buffer;
4793
4794                 case PGC_STRING:
4795                         return ((struct config_string *) record)->reset_val;
4796         }
4797         return NULL;
4798 }
4799
4800 /*
4801  * Detect whether the given configuration option can only be set by
4802  * a superuser.
4803  */
4804 bool
4805 IsSuperuserConfigOption(const char *name)
4806 {
4807         struct config_generic *record;
4808
4809         record = find_option(name, ERROR);
4810         /* On an unrecognized name, don't error, just return false. */
4811         if (record == NULL)
4812                 return false;
4813         return (record->context == PGC_SUSET);
4814 }
4815
4816
4817 /*
4818  * flatten_set_variable_args
4819  *              Given a parsenode List as emitted by the grammar for SET,
4820  *              convert to the flat string representation used by GUC.
4821  *
4822  * We need to be told the name of the variable the args are for, because
4823  * the flattening rules vary (ugh).
4824  *
4825  * The result is NULL if input is NIL (ie, SET ... TO DEFAULT), otherwise
4826  * a palloc'd string.
4827  */
4828 char *
4829 flatten_set_variable_args(const char *name, List *args)
4830 {
4831         struct config_generic *record;
4832         int                     flags;
4833         StringInfoData buf;
4834         ListCell   *l;
4835
4836         /*
4837          * Fast path if just DEFAULT.  We do not check the variable name in this
4838          * case --- necessary for RESET ALL to work correctly.
4839          */
4840         if (args == NIL)
4841                 return NULL;
4842
4843         /* Else get flags for the variable */
4844         record = find_option(name, ERROR);
4845         if (record == NULL)
4846                 ereport(ERROR,
4847                                 (errcode(ERRCODE_UNDEFINED_OBJECT),
4848                            errmsg("unrecognized configuration parameter \"%s\"", name)));
4849
4850         flags = record->flags;
4851
4852         /* Complain if list input and non-list variable */
4853         if ((flags & GUC_LIST_INPUT) == 0 &&
4854                 list_length(args) != 1)
4855                 ereport(ERROR,
4856                                 (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
4857                                  errmsg("SET %s takes only one argument", name)));
4858
4859         initStringInfo(&buf);
4860
4861         foreach(l, args)
4862         {
4863                 A_Const    *arg = (A_Const *) lfirst(l);
4864                 char       *val;
4865
4866                 if (l != list_head(args))
4867                         appendStringInfo(&buf, ", ");
4868
4869                 if (!IsA(arg, A_Const))
4870                         elog(ERROR, "unrecognized node type: %d", (int) nodeTag(arg));
4871
4872                 switch (nodeTag(&arg->val))
4873                 {
4874                         case T_Integer:
4875                                 appendStringInfo(&buf, "%ld", intVal(&arg->val));
4876                                 break;
4877                         case T_Float:
4878                                 /* represented as a string, so just copy it */
4879                                 appendStringInfoString(&buf, strVal(&arg->val));
4880                                 break;
4881                         case T_String:
4882                                 val = strVal(&arg->val);
4883                                 if (arg->typename != NULL)
4884                                 {
4885                                         /*
4886                                          * Must be a ConstInterval argument for TIME ZONE. Coerce
4887                                          * to interval and back to normalize the value and account
4888                                          * for any typmod.
4889                                          */
4890                                         int32           typmod;
4891                                         Datum           interval;
4892                                         char       *intervalout;
4893
4894                                         typmod = typenameTypeMod(NULL, arg->typename, INTERVALOID);
4895
4896                                         interval =
4897                                                 DirectFunctionCall3(interval_in,
4898                                                                                         CStringGetDatum(val),
4899                                                                                         ObjectIdGetDatum(InvalidOid),
4900                                                                                         Int32GetDatum(typmod));
4901
4902                                         intervalout =
4903                                                 DatumGetCString(DirectFunctionCall1(interval_out,
4904                                                                                                                         interval));
4905                                         appendStringInfo(&buf, "INTERVAL '%s'", intervalout);
4906                                 }
4907                                 else
4908                                 {
4909                                         /*
4910                                          * Plain string literal or identifier.  For quote mode,
4911                                          * quote it if it's not a vanilla identifier.
4912                                          */
4913                                         if (flags & GUC_LIST_QUOTE)
4914                                                 appendStringInfoString(&buf, quote_identifier(val));
4915                                         else
4916                                                 appendStringInfoString(&buf, val);
4917                                 }
4918                                 break;
4919                         default:
4920                                 elog(ERROR, "unrecognized node type: %d",
4921                                          (int) nodeTag(&arg->val));
4922                                 break;
4923                 }
4924         }
4925
4926         return buf.data;
4927 }
4928
4929
4930 /*
4931  * SET command
4932  */
4933 void
4934 SetPGVariable(const char *name, List *args, bool is_local)
4935 {
4936         char       *argstring = flatten_set_variable_args(name, args);
4937
4938         /* Note SET DEFAULT (argstring == NULL) is equivalent to RESET */
4939         set_config_option(name,
4940                                           argstring,
4941                                           (superuser() ? PGC_SUSET : PGC_USERSET),
4942                                           PGC_S_SESSION,
4943                                           is_local,
4944                                           true);
4945 }
4946
4947 /*
4948  * SET command wrapped as a SQL callable function.
4949  */
4950 Datum
4951 set_config_by_name(PG_FUNCTION_ARGS)
4952 {
4953         char       *name;
4954         char       *value;
4955         char       *new_value;
4956         bool            is_local;
4957         text       *result_text;
4958
4959         if (PG_ARGISNULL(0))
4960                 ereport(ERROR,
4961                                 (errcode(ERRCODE_NULL_VALUE_NOT_ALLOWED),
4962                                  errmsg("SET requires parameter name")));
4963
4964         /* Get the GUC variable name */
4965         name = DatumGetCString(DirectFunctionCall1(textout, PG_GETARG_DATUM(0)));
4966
4967         /* Get the desired value or set to NULL for a reset request */
4968         if (PG_ARGISNULL(1))
4969                 value = NULL;
4970         else
4971                 value = DatumGetCString(DirectFunctionCall1(textout, PG_GETARG_DATUM(1)));
4972
4973         /*
4974          * Get the desired state of is_local. Default to false if provided value
4975          * is NULL
4976          */
4977         if (PG_ARGISNULL(2))
4978                 is_local = false;
4979         else
4980                 is_local = PG_GETARG_BOOL(2);
4981
4982         /* Note SET DEFAULT (argstring == NULL) is equivalent to RESET */
4983         set_config_option(name,
4984                                           value,
4985                                           (superuser() ? PGC_SUSET : PGC_USERSET),
4986                                           PGC_S_SESSION,
4987                                           is_local,
4988                                           true);
4989
4990         /* get the new current value */
4991         new_value = GetConfigOptionByName(name, NULL);
4992
4993         /* Convert return string to text */
4994         result_text = DatumGetTextP(DirectFunctionCall1(textin, CStringGetDatum(new_value)));
4995
4996         /* return it */
4997         PG_RETURN_TEXT_P(result_text);
4998 }
4999
5000 static void
5001 define_custom_variable(struct config_generic * variable)
5002 {
5003         const char *name = variable->name;
5004         const char **nameAddr = &name;
5005         const char *value;
5006         struct config_string *pHolder;
5007         struct config_generic **res = (struct config_generic **) bsearch(
5008                                                                                                                   (void *) &nameAddr,
5009                                                                                                           (void *) guc_variables,
5010                                                                                                                    num_guc_variables,
5011                                                                                          sizeof(struct config_generic *),
5012                                                                                                                         guc_var_compare);
5013
5014         if (res == NULL)
5015         {
5016                 add_guc_variable(variable, ERROR);
5017                 return;
5018         }
5019
5020         /*
5021          * This better be a placeholder
5022          */
5023         if (((*res)->flags & GUC_CUSTOM_PLACEHOLDER) == 0)
5024                 ereport(ERROR,
5025                                 (errcode(ERRCODE_INTERNAL_ERROR),
5026                                  errmsg("attempt to redefine parameter \"%s\"", name)));
5027
5028         Assert((*res)->vartype == PGC_STRING);
5029         pHolder = (struct config_string *) * res;
5030
5031         /* We have the same name, no sorting is necessary */
5032         *res = variable;
5033
5034         value = *pHolder->variable;
5035
5036         /*
5037          * Assign the string value stored in the placeholder to the real variable.
5038          *
5039          * XXX this is not really good enough --- it should be a nontransactional
5040          * assignment, since we don't want it to roll back if the current xact
5041          * fails later.
5042          */
5043         set_config_option(name, value,
5044                                           pHolder->gen.context, pHolder->gen.source,
5045                                           false, true);
5046
5047         /*
5048          * Free up as much as we conveniently can of the placeholder structure
5049          * (this neglects any stack items...)
5050          */
5051         set_string_field(pHolder, pHolder->variable, NULL);
5052         set_string_field(pHolder, &pHolder->reset_val, NULL);
5053         set_string_field(pHolder, &pHolder->tentative_val, NULL);
5054
5055         free(pHolder);
5056 }
5057
5058 static void
5059 init_custom_variable(struct config_generic * gen,
5060                                          const char *name,
5061                                          const char *short_desc,
5062                                          const char *long_desc,
5063                                          GucContext context,
5064                                          enum config_type type)
5065 {
5066         gen->name = guc_strdup(ERROR, name);
5067         gen->context = context;
5068         gen->group = CUSTOM_OPTIONS;
5069         gen->short_desc = short_desc;
5070         gen->long_desc = long_desc;
5071         gen->vartype = type;
5072 }
5073
5074 void
5075 DefineCustomBoolVariable(const char *name,
5076                                                  const char *short_desc,
5077                                                  const char *long_desc,
5078                                                  bool *valueAddr,
5079                                                  GucContext context,
5080                                                  GucBoolAssignHook assign_hook,
5081                                                  GucShowHook show_hook)
5082 {
5083         size_t          sz = sizeof(struct config_bool);
5084         struct config_bool *var = (struct config_bool *) guc_malloc(ERROR, sz);
5085
5086         memset(var, 0, sz);
5087         init_custom_variable(&var->gen, name, short_desc, long_desc, context, PGC_BOOL);
5088
5089         var->variable = valueAddr;
5090         var->reset_val = *valueAddr;
5091         var->assign_hook = assign_hook;
5092         var->show_hook = show_hook;
5093         define_custom_variable(&var->gen);
5094 }
5095
5096 void
5097 DefineCustomIntVariable(const char *name,
5098                                                 const char *short_desc,
5099                                                 const char *long_desc,
5100                                                 int *valueAddr,
5101                                                 int minValue,
5102                                                 int maxValue,
5103                                                 GucContext context,
5104                                                 GucIntAssignHook assign_hook,
5105                                                 GucShowHook show_hook)
5106 {
5107         size_t          sz = sizeof(struct config_int);
5108         struct config_int *var = (struct config_int *) guc_malloc(ERROR, sz);
5109
5110         memset(var, 0, sz);
5111         init_custom_variable(&var->gen, name, short_desc, long_desc, context, PGC_INT);
5112
5113         var->variable = valueAddr;
5114         var->reset_val = *valueAddr;
5115         var->min = minValue;
5116         var->max = maxValue;
5117         var->assign_hook = assign_hook;
5118         var->show_hook = show_hook;
5119         define_custom_variable(&var->gen);
5120 }
5121
5122 void
5123 DefineCustomRealVariable(const char *name,
5124                                                  const char *short_desc,
5125                                                  const char *long_desc,
5126                                                  double *valueAddr,
5127                                                  double minValue,
5128                                                  double maxValue,
5129                                                  GucContext context,
5130                                                  GucRealAssignHook assign_hook,
5131                                                  GucShowHook show_hook)
5132 {
5133         size_t          sz = sizeof(struct config_real);
5134         struct config_real *var = (struct config_real *) guc_malloc(ERROR, sz);
5135
5136         memset(var, 0, sz);
5137         init_custom_variable(&var->gen, name, short_desc, long_desc, context, PGC_REAL);
5138
5139         var->variable = valueAddr;
5140         var->reset_val = *valueAddr;
5141         var->min = minValue;
5142         var->max = maxValue;
5143         var->assign_hook = assign_hook;
5144         var->show_hook = show_hook;
5145         define_custom_variable(&var->gen);
5146 }
5147
5148 void
5149 DefineCustomStringVariable(const char *name,
5150                                                    const char *short_desc,
5151                                                    const char *long_desc,
5152                                                    char **valueAddr,
5153                                                    GucContext context,
5154                                                    GucStringAssignHook assign_hook,
5155                                                    GucShowHook show_hook)
5156 {
5157         size_t          sz = sizeof(struct config_string);
5158         struct config_string *var = (struct config_string *) guc_malloc(ERROR, sz);
5159
5160         memset(var, 0, sz);
5161         init_custom_variable(&var->gen, name, short_desc, long_desc, context, PGC_STRING);
5162
5163         var->variable = valueAddr;
5164         var->reset_val = *valueAddr;
5165         var->assign_hook = assign_hook;
5166         var->show_hook = show_hook;
5167         define_custom_variable(&var->gen);
5168 }
5169
5170 void
5171 EmitWarningsOnPlaceholders(const char *className)
5172 {
5173         struct config_generic **vars = guc_variables;
5174         struct config_generic **last = vars + num_guc_variables;
5175
5176         int                     nameLen = strlen(className);
5177
5178         while (vars < last)
5179         {
5180                 struct config_generic *var = *vars++;
5181
5182                 if ((var->flags & GUC_CUSTOM_PLACEHOLDER) != 0 &&
5183                         strncmp(className, var->name, nameLen) == 0 &&
5184                         var->name[nameLen] == GUC_QUALIFIER_SEPARATOR)
5185                 {
5186                         ereport(INFO,
5187                                         (errcode(ERRCODE_UNDEFINED_OBJECT),
5188                                          errmsg("unrecognized configuration parameter \"%s\"", var->name)));
5189                 }
5190         }
5191 }
5192
5193
5194 /*
5195  * SHOW command
5196  */
5197 void
5198 GetPGVariable(const char *name, DestReceiver *dest)
5199 {
5200         if (pg_strcasecmp(name, "all") == 0)
5201                 ShowAllGUCConfig(dest);
5202         else
5203                 ShowGUCConfigOption(name, dest);
5204 }
5205
5206 TupleDesc
5207 GetPGVariableResultDesc(const char *name)
5208 {
5209         TupleDesc       tupdesc;
5210
5211         if (pg_strcasecmp(name, "all") == 0)
5212         {
5213                 /* need a tuple descriptor representing three TEXT columns */
5214                 tupdesc = CreateTemplateTupleDesc(3, false);
5215                 TupleDescInitEntry(tupdesc, (AttrNumber) 1, "name",
5216                                                    TEXTOID, -1, 0);
5217                 TupleDescInitEntry(tupdesc, (AttrNumber) 2, "setting",
5218                                                    TEXTOID, -1, 0);
5219                 TupleDescInitEntry(tupdesc, (AttrNumber) 3, "description",
5220                                                    TEXTOID, -1, 0);
5221
5222         }
5223         else
5224         {
5225                 const char *varname;
5226
5227                 /* Get the canonical spelling of name */
5228                 (void) GetConfigOptionByName(name, &varname);
5229
5230                 /* need a tuple descriptor representing a single TEXT column */
5231                 tupdesc = CreateTemplateTupleDesc(1, false);
5232                 TupleDescInitEntry(tupdesc, (AttrNumber) 1, varname,
5233                                                    TEXTOID, -1, 0);
5234         }
5235         return tupdesc;
5236 }
5237
5238 /*
5239  * RESET command
5240  */
5241 void
5242 ResetPGVariable(const char *name, bool isTopLevel)
5243 {
5244         if (pg_strcasecmp(name, "all") == 0)
5245                 ResetAllOptions();
5246         else
5247                 set_config_option(name,
5248                                                   NULL,
5249                                                   (superuser() ? PGC_SUSET : PGC_USERSET),
5250                                                   PGC_S_SESSION,
5251                                                   false,
5252                                                   true);
5253 }
5254
5255
5256 /*
5257  * SHOW command
5258  */
5259 static void
5260 ShowGUCConfigOption(const char *name, DestReceiver *dest)
5261 {
5262         TupOutputState *tstate;
5263         TupleDesc       tupdesc;
5264         const char *varname;
5265         char       *value;
5266
5267         /* Get the value and canonical spelling of name */
5268         value = GetConfigOptionByName(name, &varname);
5269
5270         /* need a tuple descriptor representing a single TEXT column */
5271         tupdesc = CreateTemplateTupleDesc(1, false);
5272         TupleDescInitEntry(tupdesc, (AttrNumber) 1, varname,
5273                                            TEXTOID, -1, 0);
5274
5275         /* prepare for projection of tuples */
5276         tstate = begin_tup_output_tupdesc(dest, tupdesc);
5277
5278         /* Send it */
5279         do_text_output_oneline(tstate, value);
5280
5281         end_tup_output(tstate);
5282 }
5283
5284 /*
5285  * SHOW ALL command
5286  */
5287 static void
5288 ShowAllGUCConfig(DestReceiver *dest)
5289 {
5290         bool            am_superuser = superuser();
5291         int                     i;
5292         TupOutputState *tstate;
5293         TupleDesc       tupdesc;
5294         char       *values[3];
5295
5296         /* need a tuple descriptor representing three TEXT columns */
5297         tupdesc = CreateTemplateTupleDesc(3, false);
5298         TupleDescInitEntry(tupdesc, (AttrNumber) 1, "name",
5299                                            TEXTOID, -1, 0);
5300         TupleDescInitEntry(tupdesc, (AttrNumber) 2, "setting",
5301                                            TEXTOID, -1, 0);
5302         TupleDescInitEntry(tupdesc, (AttrNumber) 3, "description",
5303                                            TEXTOID, -1, 0);
5304
5305
5306         /* prepare for projection of tuples */
5307         tstate = begin_tup_output_tupdesc(dest, tupdesc);
5308
5309         for (i = 0; i < num_guc_variables; i++)
5310         {
5311                 struct config_generic *conf = guc_variables[i];
5312
5313                 if ((conf->flags & GUC_NO_SHOW_ALL) ||
5314                         ((conf->flags & GUC_SUPERUSER_ONLY) && !am_superuser))
5315                         continue;
5316
5317                 /* assign to the values array */
5318                 values[0] = (char *) conf->name;
5319                 values[1] = _ShowOption(conf, true);
5320                 values[2] = (char *) conf->short_desc;
5321
5322                 /* send it to dest */
5323                 do_tup_output(tstate, values);
5324
5325                 /* clean up */
5326                 if (values[1] != NULL)
5327                         pfree(values[1]);
5328         }
5329
5330         end_tup_output(tstate);
5331 }
5332
5333 /*
5334  * Return GUC variable value by name; optionally return canonical
5335  * form of name.  Return value is palloc'd.
5336  */
5337 char *
5338 GetConfigOptionByName(const char *name, const char **varname)
5339 {
5340         struct config_generic *record;
5341
5342         record = find_option(name, ERROR);
5343         if (record == NULL)
5344                 ereport(ERROR,
5345                                 (errcode(ERRCODE_UNDEFINED_OBJECT),
5346                            errmsg("unrecognized configuration parameter \"%s\"", name)));
5347         if ((record->flags & GUC_SUPERUSER_ONLY) && !superuser())
5348                 ereport(ERROR,
5349                                 (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
5350                                  errmsg("must be superuser to examine \"%s\"", name)));
5351
5352         if (varname)
5353                 *varname = record->name;
5354
5355         return _ShowOption(record, true);
5356 }
5357
5358 /*
5359  * Return GUC variable value by variable number; optionally return canonical
5360  * form of name.  Return value is palloc'd.
5361  */
5362 void
5363 GetConfigOptionByNum(int varnum, const char **values, bool *noshow)
5364 {
5365         char            buffer[256];
5366         struct config_generic *conf;
5367
5368         /* check requested variable number valid */
5369         Assert((varnum >= 0) && (varnum < num_guc_variables));
5370
5371         conf = guc_variables[varnum];
5372
5373         if (noshow)
5374         {
5375                 if ((conf->flags & GUC_NO_SHOW_ALL) ||
5376                         ((conf->flags & GUC_SUPERUSER_ONLY) && !superuser()))
5377                         *noshow = true;
5378                 else
5379                         *noshow = false;
5380         }
5381
5382         /* first get the generic attributes */
5383
5384         /* name */
5385         values[0] = conf->name;
5386
5387         /* setting : use _ShowOption in order to avoid duplicating the logic */
5388         values[1] = _ShowOption(conf, false);
5389
5390         /* unit */
5391         if (conf->vartype == PGC_INT)
5392         {
5393                 static char buf[8];
5394
5395                 switch (conf->flags & (GUC_UNIT_MEMORY | GUC_UNIT_TIME))
5396                 {
5397                         case GUC_UNIT_KB:
5398                                 values[2] = "kB";
5399                                 break;
5400                         case GUC_UNIT_BLOCKS:
5401                                 snprintf(buf, sizeof(buf), "%dkB", BLCKSZ / 1024);
5402                                 values[2] = buf;
5403                                 break;
5404                         case GUC_UNIT_XBLOCKS:
5405                                 snprintf(buf, sizeof(buf), "%dkB", XLOG_BLCKSZ / 1024);
5406                                 values[2] = buf;
5407                                 break;
5408                         case GUC_UNIT_MS:
5409                                 values[2] = "ms";
5410                                 break;
5411                         case GUC_UNIT_S:
5412                                 values[2] = "s";
5413                                 break;
5414                         case GUC_UNIT_MIN:
5415                                 values[2] = "min";
5416                                 break;
5417                         default:
5418                                 values[2] = "";
5419                                 break;
5420                 }
5421         }
5422         else
5423                 values[2] = NULL;
5424
5425         /* group */
5426         values[3] = config_group_names[conf->group];
5427
5428         /* short_desc */
5429         values[4] = conf->short_desc;
5430
5431         /* extra_desc */
5432         values[5] = conf->long_desc;
5433
5434         /* context */
5435         values[6] = GucContext_Names[conf->context];
5436
5437         /* vartype */
5438         values[7] = config_type_names[conf->vartype];
5439
5440         /* source */
5441         values[8] = GucSource_Names[conf->source];
5442
5443         /* now get the type specifc attributes */
5444         switch (conf->vartype)
5445         {
5446                 case PGC_BOOL:
5447                         {
5448                                 /* min_val */
5449                                 values[9] = NULL;
5450
5451                                 /* max_val */
5452                                 values[10] = NULL;
5453                         }
5454                         break;
5455
5456                 case PGC_INT:
5457                         {
5458                                 struct config_int *lconf = (struct config_int *) conf;
5459
5460                                 /* min_val */
5461                                 snprintf(buffer, sizeof(buffer), "%d", lconf->min);
5462                                 values[9] = pstrdup(buffer);
5463
5464                                 /* max_val */
5465                                 snprintf(buffer, sizeof(buffer), "%d", lconf->max);
5466                                 values[10] = pstrdup(buffer);
5467                         }
5468                         break;
5469
5470                 case PGC_REAL:
5471                         {
5472                                 struct config_real *lconf = (struct config_real *) conf;
5473
5474                                 /* min_val */
5475                                 snprintf(buffer, sizeof(buffer), "%g", lconf->min);
5476                                 values[9] = pstrdup(buffer);
5477
5478                                 /* max_val */
5479                                 snprintf(buffer, sizeof(buffer), "%g", lconf->max);
5480                                 values[10] = pstrdup(buffer);
5481                         }
5482                         break;
5483
5484                 case PGC_STRING:
5485                         {
5486                                 /* min_val */
5487                                 values[9] = NULL;
5488
5489                                 /* max_val */
5490                                 values[10] = NULL;
5491                         }
5492                         break;
5493
5494                 default:
5495                         {
5496                                 /*
5497                                  * should never get here, but in case we do, set 'em to NULL
5498                                  */
5499
5500                                 /* min_val */
5501                                 values[9] = NULL;
5502
5503                                 /* max_val */
5504                                 values[10] = NULL;
5505                         }
5506                         break;
5507         }
5508 }
5509
5510 /*
5511  * Return the total number of GUC variables
5512  */
5513 int
5514 GetNumConfigOptions(void)
5515 {
5516         return num_guc_variables;
5517 }
5518
5519 /*
5520  * show_config_by_name - equiv to SHOW X command but implemented as
5521  * a function.
5522  */
5523 Datum
5524 show_config_by_name(PG_FUNCTION_ARGS)
5525 {
5526         char       *varname;
5527         char       *varval;
5528         text       *result_text;
5529
5530         /* Get the GUC variable name */
5531         varname = DatumGetCString(DirectFunctionCall1(textout, PG_GETARG_DATUM(0)));
5532
5533         /* Get the value */
5534         varval = GetConfigOptionByName(varname, NULL);
5535
5536         /* Convert to text */
5537         result_text = DatumGetTextP(DirectFunctionCall1(textin, CStringGetDatum(varval)));
5538
5539         /* return it */
5540         PG_RETURN_TEXT_P(result_text);
5541 }
5542
5543 /*
5544  * show_all_settings - equiv to SHOW ALL command but implemented as
5545  * a Table Function.
5546  */
5547 #define NUM_PG_SETTINGS_ATTS    11
5548
5549 Datum
5550 show_all_settings(PG_FUNCTION_ARGS)
5551 {
5552         FuncCallContext *funcctx;
5553         TupleDesc       tupdesc;
5554         int                     call_cntr;
5555         int                     max_calls;
5556         AttInMetadata *attinmeta;
5557         MemoryContext oldcontext;
5558
5559         /* stuff done only on the first call of the function */
5560         if (SRF_IS_FIRSTCALL())
5561         {
5562                 /* create a function context for cross-call persistence */
5563                 funcctx = SRF_FIRSTCALL_INIT();
5564
5565                 /*
5566                  * switch to memory context appropriate for multiple function calls
5567                  */
5568                 oldcontext = MemoryContextSwitchTo(funcctx->multi_call_memory_ctx);
5569
5570                 /*
5571                  * need a tuple descriptor representing NUM_PG_SETTINGS_ATTS columns
5572                  * of the appropriate types
5573                  */
5574                 tupdesc = CreateTemplateTupleDesc(NUM_PG_SETTINGS_ATTS, false);
5575                 TupleDescInitEntry(tupdesc, (AttrNumber) 1, "name",
5576                                                    TEXTOID, -1, 0);
5577                 TupleDescInitEntry(tupdesc, (AttrNumber) 2, "setting",
5578                                                    TEXTOID, -1, 0);
5579                 TupleDescInitEntry(tupdesc, (AttrNumber) 3, "unit",
5580                                                    TEXTOID, -1, 0);
5581                 TupleDescInitEntry(tupdesc, (AttrNumber) 4, "category",
5582                                                    TEXTOID, -1, 0);
5583                 TupleDescInitEntry(tupdesc, (AttrNumber) 5, "short_desc",
5584                                                    TEXTOID, -1, 0);
5585                 TupleDescInitEntry(tupdesc, (AttrNumber) 6, "extra_desc",
5586                                                    TEXTOID, -1, 0);
5587                 TupleDescInitEntry(tupdesc, (AttrNumber) 7, "context",
5588                                                    TEXTOID, -1, 0);
5589                 TupleDescInitEntry(tupdesc, (AttrNumber) 8, "vartype",
5590                                                    TEXTOID, -1, 0);
5591                 TupleDescInitEntry(tupdesc, (AttrNumber) 9, "source",
5592                                                    TEXTOID, -1, 0);
5593                 TupleDescInitEntry(tupdesc, (AttrNumber) 10, "min_val",
5594                                                    TEXTOID, -1, 0);
5595                 TupleDescInitEntry(tupdesc, (AttrNumber) 11, "max_val",
5596                                                    TEXTOID, -1, 0);
5597
5598                 /*
5599                  * Generate attribute metadata needed later to produce tuples from raw
5600                  * C strings
5601                  */
5602                 attinmeta = TupleDescGetAttInMetadata(tupdesc);
5603                 funcctx->attinmeta = attinmeta;
5604
5605                 /* total number of tuples to be returned */
5606                 funcctx->max_calls = GetNumConfigOptions();
5607
5608                 MemoryContextSwitchTo(oldcontext);
5609         }
5610
5611         /* stuff done on every call of the function */
5612         funcctx = SRF_PERCALL_SETUP();
5613
5614         call_cntr = funcctx->call_cntr;
5615         max_calls = funcctx->max_calls;
5616         attinmeta = funcctx->attinmeta;
5617
5618         if (call_cntr < max_calls)      /* do when there is more left to send */
5619         {
5620                 char       *values[NUM_PG_SETTINGS_ATTS];
5621                 bool            noshow;
5622                 HeapTuple       tuple;
5623                 Datum           result;
5624
5625                 /*
5626                  * Get the next visible GUC variable name and value
5627                  */
5628                 do
5629                 {
5630                         GetConfigOptionByNum(call_cntr, (const char **) values, &noshow);
5631                         if (noshow)
5632                         {
5633                                 /* bump the counter and get the next config setting */
5634                                 call_cntr = ++funcctx->call_cntr;
5635
5636                                 /* make sure we haven't gone too far now */
5637                                 if (call_cntr >= max_calls)
5638                                         SRF_RETURN_DONE(funcctx);
5639                         }
5640                 } while (noshow);
5641
5642                 /* build a tuple */
5643                 tuple = BuildTupleFromCStrings(attinmeta, values);
5644
5645                 /* make the tuple into a datum */
5646                 result = HeapTupleGetDatum(tuple);
5647
5648                 SRF_RETURN_NEXT(funcctx, result);
5649         }
5650         else
5651         {
5652                 /* do when there is no more left */
5653                 SRF_RETURN_DONE(funcctx);
5654         }
5655 }
5656
5657 static char *
5658 _ShowOption(struct config_generic * record, bool use_units)
5659 {
5660         char            buffer[256];
5661         const char *val;
5662
5663         switch (record->vartype)
5664         {
5665                 case PGC_BOOL:
5666                         {
5667                                 struct config_bool *conf = (struct config_bool *) record;
5668
5669                                 if (conf->show_hook)
5670                                         val = (*conf->show_hook) ();
5671                                 else
5672                                         val = *conf->variable ? "on" : "off";
5673                         }
5674                         break;
5675
5676                 case PGC_INT:
5677                         {
5678                                 struct config_int *conf = (struct config_int *) record;
5679
5680                                 if (conf->show_hook)
5681                                         val = (*conf->show_hook) ();
5682                                 else
5683                                 {
5684                                         char            unit[4];
5685                                         int                     result = *conf->variable;
5686
5687                                         if (use_units && result > 0 && (record->flags & GUC_UNIT_MEMORY))
5688                                         {
5689                                                 switch (record->flags & GUC_UNIT_MEMORY)
5690                                                 {
5691                                                         case GUC_UNIT_BLOCKS:
5692                                                                 result *= BLCKSZ / 1024;
5693                                                                 break;
5694                                                         case GUC_UNIT_XBLOCKS:
5695                                                                 result *= XLOG_BLCKSZ / 1024;
5696                                                                 break;
5697                                                 }
5698
5699                                                 if (result % KB_PER_GB == 0)
5700                                                 {
5701                                                         result /= KB_PER_GB;
5702                                                         strcpy(unit, "GB");
5703                                                 }
5704                                                 else if (result % KB_PER_MB == 0)
5705                                                 {
5706                                                         result /= KB_PER_MB;
5707                                                         strcpy(unit, "MB");
5708                                                 }
5709                                                 else
5710                                                 {
5711                                                         strcpy(unit, "kB");
5712                                                 }
5713                                         }
5714                                         else if (use_units && result > 0 && (record->flags & GUC_UNIT_TIME))
5715                                         {
5716                                                 switch (record->flags & GUC_UNIT_TIME)
5717                                                 {
5718                                                         case GUC_UNIT_S:
5719                                                                 result *= MS_PER_S;
5720                                                                 break;
5721                                                         case GUC_UNIT_MIN:
5722                                                                 result *= MS_PER_MIN;
5723                                                                 break;
5724                                                 }
5725
5726                                                 if (result % MS_PER_D == 0)
5727                                                 {
5728                                                         result /= MS_PER_D;
5729                                                         strcpy(unit, "d");
5730                                                 }
5731                                                 else if (result % MS_PER_H == 0)
5732                                                 {
5733                                                         result /= MS_PER_H;
5734                                                         strcpy(unit, "h");
5735                                                 }
5736                                                 else if (result % MS_PER_MIN == 0)
5737                                                 {
5738                                                         result /= MS_PER_MIN;
5739                                                         strcpy(unit, "min");
5740                                                 }
5741                                                 else if (result % MS_PER_S == 0)
5742                                                 {
5743                                                         result /= MS_PER_S;
5744                                                         strcpy(unit, "s");
5745                                                 }
5746                                                 else
5747                                                 {
5748                                                         strcpy(unit, "ms");
5749                                                 }
5750                                         }
5751                                         else
5752                                                 strcpy(unit, "");
5753
5754                                         snprintf(buffer, sizeof(buffer), "%d%s",
5755                                                          (int) result, unit);
5756                                         val = buffer;
5757                                 }
5758                         }
5759                         break;
5760
5761                 case PGC_REAL:
5762                         {
5763                                 struct config_real *conf = (struct config_real *) record;
5764
5765                                 if (conf->show_hook)
5766                                         val = (*conf->show_hook) ();
5767                                 else
5768                                 {
5769                                         snprintf(buffer, sizeof(buffer), "%g",
5770                                                          *conf->variable);
5771                                         val = buffer;
5772                                 }
5773                         }
5774                         break;
5775
5776                 case PGC_STRING:
5777                         {
5778                                 struct config_string *conf = (struct config_string *) record;
5779
5780                                 if (conf->show_hook)
5781                                         val = (*conf->show_hook) ();
5782                                 else if (*conf->variable && **conf->variable)
5783                                         val = *conf->variable;
5784                                 else
5785                                         val = "";
5786                         }
5787                         break;
5788
5789                 default:
5790                         /* just to keep compiler quiet */
5791                         val = "???";
5792                         break;
5793         }
5794
5795         return pstrdup(val);
5796 }
5797
5798
5799 static bool
5800 is_newvalue_equal(struct config_generic * record, const char *newvalue)
5801 {
5802         switch (record->vartype)
5803         {
5804                 case PGC_BOOL:
5805                         {
5806                                 struct config_bool *conf = (struct config_bool *) record;
5807                                 bool            newval;
5808
5809                                 return parse_bool(newvalue, &newval)
5810                                         && *conf->variable == newval;
5811                         }
5812                 case PGC_INT:
5813                         {
5814                                 struct config_int *conf = (struct config_int *) record;
5815                                 int                     newval;
5816
5817                                 return parse_int(newvalue, &newval, record->flags, NULL)
5818                                         && *conf->variable == newval;
5819                         }
5820                 case PGC_REAL:
5821                         {
5822                                 struct config_real *conf = (struct config_real *) record;
5823                                 double          newval;
5824
5825                                 return parse_real(newvalue, &newval)
5826                                         && *conf->variable == newval;
5827                         }
5828                 case PGC_STRING:
5829                         {
5830                                 struct config_string *conf = (struct config_string *) record;
5831
5832                                 return strcmp(*conf->variable, newvalue) == 0;
5833                         }
5834         }
5835
5836         return false;
5837 }
5838
5839
5840 #ifdef EXEC_BACKEND
5841
5842 /*
5843  *      This routine dumps out all non-default GUC options into a binary
5844  *      file that is read by all exec'ed backends.  The format is:
5845  *
5846  *              variable name, string, null terminated
5847  *              variable value, string, null terminated
5848  *              variable source, integer
5849  */
5850 void
5851 write_nondefault_variables(GucContext context)
5852 {
5853         int                     i;
5854         int                     elevel;
5855         FILE       *fp;
5856
5857         Assert(context == PGC_POSTMASTER || context == PGC_SIGHUP);
5858
5859         elevel = (context == PGC_SIGHUP) ? LOG : ERROR;
5860
5861         /*
5862          * Open file
5863          */
5864         fp = AllocateFile(CONFIG_EXEC_PARAMS_NEW, "w");
5865         if (!fp)
5866         {
5867                 ereport(elevel,
5868                                 (errcode_for_file_access(),
5869                                  errmsg("could not write to file \"%s\": %m",
5870                                                 CONFIG_EXEC_PARAMS_NEW)));
5871                 return;
5872         }
5873
5874         for (i = 0; i < num_guc_variables; i++)
5875         {
5876                 struct config_generic *gconf = guc_variables[i];
5877
5878                 if (gconf->source != PGC_S_DEFAULT)
5879                 {
5880                         fprintf(fp, "%s", gconf->name);
5881                         fputc(0, fp);
5882
5883                         switch (gconf->vartype)
5884                         {
5885                                 case PGC_BOOL:
5886                                         {
5887                                                 struct config_bool *conf = (struct config_bool *) gconf;
5888
5889                                                 if (*conf->variable == 0)
5890                                                         fprintf(fp, "false");
5891                                                 else
5892                                                         fprintf(fp, "true");
5893                                         }
5894                                         break;
5895
5896                                 case PGC_INT:
5897                                         {
5898                                                 struct config_int *conf = (struct config_int *) gconf;
5899
5900                                                 fprintf(fp, "%d", *conf->variable);
5901                                         }
5902                                         break;
5903
5904                                 case PGC_REAL:
5905                                         {
5906                                                 struct config_real *conf = (struct config_real *) gconf;
5907
5908                                                 /* Could lose precision here? */
5909                                                 fprintf(fp, "%f", *conf->variable);
5910                                         }
5911                                         break;
5912
5913                                 case PGC_STRING:
5914                                         {
5915                                                 struct config_string *conf = (struct config_string *) gconf;
5916
5917                                                 fprintf(fp, "%s", *conf->variable);
5918                                         }
5919                                         break;
5920                         }
5921
5922                         fputc(0, fp);
5923
5924                         fwrite(&gconf->source, sizeof(gconf->source), 1, fp);
5925                 }
5926         }
5927
5928         if (FreeFile(fp))
5929         {
5930                 ereport(elevel,
5931                                 (errcode_for_file_access(),
5932                                  errmsg("could not write to file \"%s\": %m",
5933                                                 CONFIG_EXEC_PARAMS_NEW)));
5934                 return;
5935         }
5936
5937         /*
5938          * Put new file in place.  This could delay on Win32, but we don't hold
5939          * any exclusive locks.
5940          */
5941         rename(CONFIG_EXEC_PARAMS_NEW, CONFIG_EXEC_PARAMS);
5942 }
5943
5944
5945 /*
5946  *      Read string, including null byte from file
5947  *
5948  *      Return NULL on EOF and nothing read
5949  */
5950 static char *
5951 read_string_with_null(FILE *fp)
5952 {
5953         int                     i = 0,
5954                                 ch,
5955                                 maxlen = 256;
5956         char       *str = NULL;
5957
5958         do
5959         {
5960                 if ((ch = fgetc(fp)) == EOF)
5961                 {
5962                         if (i == 0)
5963                                 return NULL;
5964                         else
5965                                 elog(FATAL, "invalid format of exec config params file");
5966                 }
5967                 if (i == 0)
5968                         str = guc_malloc(FATAL, maxlen);
5969                 else if (i == maxlen)
5970                         str = guc_realloc(FATAL, str, maxlen *= 2);
5971                 str[i++] = ch;
5972         } while (ch != 0);
5973
5974         return str;
5975 }
5976
5977
5978 /*
5979  *      This routine loads a previous postmaster dump of its non-default
5980  *      settings.
5981  */
5982 void
5983 read_nondefault_variables(void)
5984 {
5985         FILE       *fp;
5986         char       *varname,
5987                            *varvalue;
5988         int                     varsource;
5989
5990         /*
5991          * Open file
5992          */
5993         fp = AllocateFile(CONFIG_EXEC_PARAMS, "r");
5994         if (!fp)
5995         {
5996                 /* File not found is fine */
5997                 if (errno != ENOENT)
5998                         ereport(FATAL,
5999                                         (errcode_for_file_access(),
6000                                          errmsg("could not read from file \"%s\": %m",
6001                                                         CONFIG_EXEC_PARAMS)));
6002                 return;
6003         }
6004
6005         for (;;)
6006         {
6007                 struct config_generic *record;
6008
6009                 if ((varname = read_string_with_null(fp)) == NULL)
6010                         break;
6011
6012                 if ((record = find_option(varname, FATAL)) == NULL)
6013                         elog(FATAL, "failed to locate variable %s in exec config params file", varname);
6014                 if ((varvalue = read_string_with_null(fp)) == NULL)
6015                         elog(FATAL, "invalid format of exec config params file");
6016                 if (fread(&varsource, sizeof(varsource), 1, fp) == 0)
6017                         elog(FATAL, "invalid format of exec config params file");
6018
6019                 (void) set_config_option(varname, varvalue, record->context,
6020                                                                  varsource, false, true);
6021                 free(varname);
6022                 free(varvalue);
6023         }
6024
6025         FreeFile(fp);
6026 }
6027 #endif   /* EXEC_BACKEND */
6028
6029
6030 /*
6031  * A little "long argument" simulation, although not quite GNU
6032  * compliant. Takes a string of the form "some-option=some value" and
6033  * returns name = "some_option" and value = "some value" in malloc'ed
6034  * storage. Note that '-' is converted to '_' in the option name. If
6035  * there is no '=' in the input string then value will be NULL.
6036  */
6037 void
6038 ParseLongOption(const char *string, char **name, char **value)
6039 {
6040         size_t          equal_pos;
6041         char       *cp;
6042
6043         AssertArg(string);
6044         AssertArg(name);
6045         AssertArg(value);
6046
6047         equal_pos = strcspn(string, "=");
6048
6049         if (string[equal_pos] == '=')
6050         {
6051                 *name = guc_malloc(FATAL, equal_pos + 1);
6052                 strlcpy(*name, string, equal_pos + 1);
6053
6054                 *value = guc_strdup(FATAL, &string[equal_pos + 1]);
6055         }
6056         else
6057         {
6058                 /* no equal sign in string */
6059                 *name = guc_strdup(FATAL, string);
6060                 *value = NULL;
6061         }
6062
6063         for (cp = *name; *cp; cp++)
6064                 if (*cp == '-')
6065                         *cp = '_';
6066 }
6067
6068
6069 /*
6070  * Handle options fetched from pg_database.datconfig or pg_authid.rolconfig.
6071  * The array parameter must be an array of TEXT (it must not be NULL).
6072  */
6073 void
6074 ProcessGUCArray(ArrayType *array, GucSource source)
6075 {
6076         int                     i;
6077
6078         Assert(array != NULL);
6079         Assert(ARR_ELEMTYPE(array) == TEXTOID);
6080         Assert(ARR_NDIM(array) == 1);
6081         Assert(ARR_LBOUND(array)[0] == 1);
6082         Assert(source == PGC_S_DATABASE || source == PGC_S_USER);
6083
6084         for (i = 1; i <= ARR_DIMS(array)[0]; i++)
6085         {
6086                 Datum           d;
6087                 bool            isnull;
6088                 char       *s;
6089                 char       *name;
6090                 char       *value;
6091
6092                 d = array_ref(array, 1, &i,
6093                                           -1 /* varlenarray */ ,
6094                                           -1 /* TEXT's typlen */ ,
6095                                           false /* TEXT's typbyval */ ,
6096                                           'i' /* TEXT's typalign */ ,
6097                                           &isnull);
6098
6099                 if (isnull)
6100                         continue;
6101
6102                 s = DatumGetCString(DirectFunctionCall1(textout, d));
6103
6104                 ParseLongOption(s, &name, &value);
6105                 if (!value)
6106                 {
6107                         ereport(WARNING,
6108                                         (errcode(ERRCODE_SYNTAX_ERROR),
6109                           errmsg("could not parse setting for parameter \"%s\"", name)));
6110                         free(name);
6111                         continue;
6112                 }
6113
6114                 /*
6115                  * We process all these options at SUSET level.  We assume that the
6116                  * right to insert an option into pg_database or pg_authid was checked
6117                  * when it was inserted.
6118                  */
6119                 SetConfigOption(name, value, PGC_SUSET, source);
6120
6121                 free(name);
6122                 if (value)
6123                         free(value);
6124         }
6125 }
6126
6127
6128 /*
6129  * Add an entry to an option array.  The array parameter may be NULL
6130  * to indicate the current table entry is NULL.
6131  */
6132 ArrayType *
6133 GUCArrayAdd(ArrayType *array, const char *name, const char *value)
6134 {
6135         const char *varname;
6136         Datum           datum;
6137         char       *newval;
6138         ArrayType  *a;
6139
6140         Assert(name);
6141         Assert(value);
6142
6143         /* test if the option is valid */
6144         set_config_option(name, value,
6145                                           superuser() ? PGC_SUSET : PGC_USERSET,
6146                                           PGC_S_TEST, false, false);
6147
6148         /* convert name to canonical spelling, so we can use plain strcmp */
6149         (void) GetConfigOptionByName(name, &varname);
6150         name = varname;
6151
6152         newval = palloc(strlen(name) + 1 + strlen(value) + 1);
6153         sprintf(newval, "%s=%s", name, value);
6154         datum = DirectFunctionCall1(textin, CStringGetDatum(newval));
6155
6156         if (array)
6157         {
6158                 int                     index;
6159                 bool            isnull;
6160                 int                     i;
6161
6162                 Assert(ARR_ELEMTYPE(array) == TEXTOID);
6163                 Assert(ARR_NDIM(array) == 1);
6164                 Assert(ARR_LBOUND(array)[0] == 1);
6165
6166                 index = ARR_DIMS(array)[0] + 1; /* add after end */
6167
6168                 for (i = 1; i <= ARR_DIMS(array)[0]; i++)
6169                 {
6170                         Datum           d;
6171                         char       *current;
6172
6173                         d = array_ref(array, 1, &i,
6174                                                   -1 /* varlenarray */ ,
6175                                                   -1 /* TEXT's typlen */ ,
6176                                                   false /* TEXT's typbyval */ ,
6177                                                   'i' /* TEXT's typalign */ ,
6178                                                   &isnull);
6179                         if (isnull)
6180                                 continue;
6181                         current = DatumGetCString(DirectFunctionCall1(textout, d));
6182                         if (strncmp(current, newval, strlen(name) + 1) == 0)
6183                         {
6184                                 index = i;
6185                                 break;
6186                         }
6187                 }
6188
6189                 a = array_set(array, 1, &index,
6190                                           datum,
6191                                           false,
6192                                           -1 /* varlena array */ ,
6193                                           -1 /* TEXT's typlen */ ,
6194                                           false /* TEXT's typbyval */ ,
6195                                           'i' /* TEXT's typalign */ );
6196         }
6197         else
6198                 a = construct_array(&datum, 1,
6199                                                         TEXTOID,
6200                                                         -1, false, 'i');
6201
6202         return a;
6203 }
6204
6205
6206 /*
6207  * Delete an entry from an option array.  The array parameter may be NULL
6208  * to indicate the current table entry is NULL.  Also, if the return value
6209  * is NULL then a null should be stored.
6210  */
6211 ArrayType *
6212 GUCArrayDelete(ArrayType *array, const char *name)
6213 {
6214         const char *varname;
6215         ArrayType  *newarray;
6216         int                     i;
6217         int                     index;
6218
6219         Assert(name);
6220
6221         /* test if the option is valid */
6222         set_config_option(name, NULL,
6223                                           superuser() ? PGC_SUSET : PGC_USERSET,
6224                                           PGC_S_TEST, false, false);
6225
6226         /* convert name to canonical spelling, so we can use plain strcmp */
6227         (void) GetConfigOptionByName(name, &varname);
6228         name = varname;
6229
6230         /* if array is currently null, then surely nothing to delete */
6231         if (!array)
6232                 return NULL;
6233
6234         newarray = NULL;
6235         index = 1;
6236
6237         for (i = 1; i <= ARR_DIMS(array)[0]; i++)
6238         {
6239                 Datum           d;
6240                 char       *val;
6241                 bool            isnull;
6242
6243                 d = array_ref(array, 1, &i,
6244                                           -1 /* varlenarray */ ,
6245                                           -1 /* TEXT's typlen */ ,
6246                                           false /* TEXT's typbyval */ ,
6247                                           'i' /* TEXT's typalign */ ,
6248                                           &isnull);
6249                 if (isnull)
6250                         continue;
6251                 val = DatumGetCString(DirectFunctionCall1(textout, d));
6252
6253                 /* ignore entry if it's what we want to delete */
6254                 if (strncmp(val, name, strlen(name)) == 0
6255                         && val[strlen(name)] == '=')
6256                         continue;
6257
6258                 /* else add it to the output array */
6259                 if (newarray)
6260                 {
6261                         newarray = array_set(newarray, 1, &index,
6262                                                                  d,
6263                                                                  false,
6264                                                                  -1 /* varlenarray */ ,
6265                                                                  -1 /* TEXT's typlen */ ,
6266                                                                  false /* TEXT's typbyval */ ,
6267                                                                  'i' /* TEXT's typalign */ );
6268                 }
6269                 else
6270                         newarray = construct_array(&d, 1,
6271                                                                            TEXTOID,
6272                                                                            -1, false, 'i');
6273
6274                 index++;
6275         }
6276
6277         return newarray;
6278 }
6279
6280
6281 /*
6282  * assign_hook subroutines
6283  */
6284
6285 static const char *
6286 assign_log_destination(const char *value, bool doit, GucSource source)
6287 {
6288         char       *rawstring;
6289         List       *elemlist;
6290         ListCell   *l;
6291         int                     newlogdest = 0;
6292
6293         /* Need a modifiable copy of string */
6294         rawstring = pstrdup(value);
6295
6296         /* Parse string into list of identifiers */
6297         if (!SplitIdentifierString(rawstring, ',', &elemlist))
6298         {
6299                 /* syntax error in list */
6300                 pfree(rawstring);
6301                 list_free(elemlist);
6302                 if (source >= PGC_S_INTERACTIVE)
6303                         ereport(ERROR,
6304                                         (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
6305                         errmsg("invalid list syntax for parameter \"log_destination\"")));
6306                 return NULL;
6307         }
6308
6309         foreach(l, elemlist)
6310         {
6311                 char       *tok = (char *) lfirst(l);
6312
6313                 if (pg_strcasecmp(tok, "stderr") == 0)
6314                         newlogdest |= LOG_DESTINATION_STDERR;
6315 #ifdef HAVE_SYSLOG
6316                 else if (pg_strcasecmp(tok, "syslog") == 0)
6317                         newlogdest |= LOG_DESTINATION_SYSLOG;
6318 #endif
6319 #ifdef WIN32
6320                 else if (pg_strcasecmp(tok, "eventlog") == 0)
6321                         newlogdest |= LOG_DESTINATION_EVENTLOG;
6322 #endif
6323                 else
6324                 {
6325                         if (source >= PGC_S_INTERACTIVE)
6326                                 ereport(ERROR,
6327                                                 (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
6328                                   errmsg("unrecognized \"log_destination\" key word: \"%s\"",
6329                                                  tok)));
6330                         pfree(rawstring);
6331                         list_free(elemlist);
6332                         return NULL;
6333                 }
6334         }
6335
6336         if (doit)
6337                 Log_destination = newlogdest;
6338
6339         pfree(rawstring);
6340         list_free(elemlist);
6341
6342         return value;
6343 }
6344
6345 #ifdef HAVE_SYSLOG
6346
6347 static const char *
6348 assign_syslog_facility(const char *facility, bool doit, GucSource source)
6349 {
6350         int                     syslog_fac;
6351
6352         if (pg_strcasecmp(facility, "LOCAL0") == 0)
6353                 syslog_fac = LOG_LOCAL0;
6354         else if (pg_strcasecmp(facility, "LOCAL1") == 0)
6355                 syslog_fac = LOG_LOCAL1;
6356         else if (pg_strcasecmp(facility, "LOCAL2") == 0)
6357                 syslog_fac = LOG_LOCAL2;
6358         else if (pg_strcasecmp(facility, "LOCAL3") == 0)
6359                 syslog_fac = LOG_LOCAL3;
6360         else if (pg_strcasecmp(facility, "LOCAL4") == 0)
6361                 syslog_fac = LOG_LOCAL4;
6362         else if (pg_strcasecmp(facility, "LOCAL5") == 0)
6363                 syslog_fac = LOG_LOCAL5;
6364         else if (pg_strcasecmp(facility, "LOCAL6") == 0)
6365                 syslog_fac = LOG_LOCAL6;
6366         else if (pg_strcasecmp(facility, "LOCAL7") == 0)
6367                 syslog_fac = LOG_LOCAL7;
6368         else
6369                 return NULL;                    /* reject */
6370
6371         if (doit)
6372         {
6373                 syslog_facility = syslog_fac;
6374                 set_syslog_parameters(syslog_ident_str ? syslog_ident_str : "postgres",
6375                                                           syslog_facility);
6376         }
6377
6378         return facility;
6379 }
6380
6381 static const char *
6382 assign_syslog_ident(const char *ident, bool doit, GucSource source)
6383 {
6384         if (doit)
6385                 set_syslog_parameters(ident, syslog_facility);
6386
6387         return ident;
6388 }
6389 #endif   /* HAVE_SYSLOG */
6390
6391
6392 static const char *
6393 assign_defaultxactisolevel(const char *newval, bool doit, GucSource source)
6394 {
6395         if (pg_strcasecmp(newval, "serializable") == 0)
6396         {
6397                 if (doit)
6398                         DefaultXactIsoLevel = XACT_SERIALIZABLE;
6399         }
6400         else if (pg_strcasecmp(newval, "repeatable read") == 0)
6401         {
6402                 if (doit)
6403                         DefaultXactIsoLevel = XACT_REPEATABLE_READ;
6404         }
6405         else if (pg_strcasecmp(newval, "read committed") == 0)
6406         {
6407                 if (doit)
6408                         DefaultXactIsoLevel = XACT_READ_COMMITTED;
6409         }
6410         else if (pg_strcasecmp(newval, "read uncommitted") == 0)
6411         {
6412                 if (doit)
6413                         DefaultXactIsoLevel = XACT_READ_UNCOMMITTED;
6414         }
6415         else
6416                 return NULL;
6417         return newval;
6418 }
6419
6420 static const char *
6421 assign_session_replication_role(const char *newval, bool doit, GucSource source)
6422 {
6423         int             newrole;
6424
6425         if (pg_strcasecmp(newval, "origin") == 0)
6426                 newrole = SESSION_REPLICATION_ROLE_ORIGIN;
6427         else if (pg_strcasecmp(newval, "replica") == 0)
6428                 newrole = SESSION_REPLICATION_ROLE_REPLICA;
6429         else if (pg_strcasecmp(newval, "local") == 0)
6430                 newrole = SESSION_REPLICATION_ROLE_LOCAL;
6431         else
6432                 return NULL;
6433
6434         /*
6435          * Must flush the plan cache when changing replication role; but don't
6436          * flush unnecessarily.
6437          */
6438         if (doit && SessionReplicationRole != newrole)
6439         {
6440                 ResetPlanCache();
6441                 SessionReplicationRole = newrole;
6442         }
6443
6444         return newval;
6445 }
6446
6447 static const char *
6448 assign_log_min_messages(const char *newval,
6449                                                 bool doit, GucSource source)
6450 {
6451         return (assign_msglvl(&log_min_messages, newval, doit, source));
6452 }
6453
6454 static const char *
6455 assign_client_min_messages(const char *newval, bool doit, GucSource source)
6456 {
6457         return (assign_msglvl(&client_min_messages, newval, doit, source));
6458 }
6459
6460 static const char *
6461 assign_min_error_statement(const char *newval, bool doit, GucSource source)
6462 {
6463         return (assign_msglvl(&log_min_error_statement, newval, doit, source));
6464 }
6465
6466 static const char *
6467 assign_msglvl(int *var, const char *newval, bool doit, GucSource source)
6468 {
6469         if (pg_strcasecmp(newval, "debug") == 0)
6470         {
6471                 if (doit)
6472                         (*var) = DEBUG2;
6473         }
6474         else if (pg_strcasecmp(newval, "debug5") == 0)
6475         {
6476                 if (doit)
6477                         (*var) = DEBUG5;
6478         }
6479         else if (pg_strcasecmp(newval, "debug4") == 0)
6480         {
6481                 if (doit)
6482                         (*var) = DEBUG4;
6483         }
6484         else if (pg_strcasecmp(newval, "debug3") == 0)
6485         {
6486                 if (doit)
6487                         (*var) = DEBUG3;
6488         }
6489         else if (pg_strcasecmp(newval, "debug2") == 0)
6490         {
6491                 if (doit)
6492                         (*var) = DEBUG2;
6493         }
6494         else if (pg_strcasecmp(newval, "debug1") == 0)
6495         {
6496                 if (doit)
6497                         (*var) = DEBUG1;
6498         }
6499         else if (pg_strcasecmp(newval, "log") == 0)
6500         {
6501                 if (doit)
6502                         (*var) = LOG;
6503         }
6504
6505         /*
6506          * Client_min_messages always prints 'info', but we allow it as a value
6507          * anyway.
6508          */
6509         else if (pg_strcasecmp(newval, "info") == 0)
6510         {
6511                 if (doit)
6512                         (*var) = INFO;
6513         }
6514         else if (pg_strcasecmp(newval, "notice") == 0)
6515         {
6516                 if (doit)
6517                         (*var) = NOTICE;
6518         }
6519         else if (pg_strcasecmp(newval, "warning") == 0)
6520         {
6521                 if (doit)
6522                         (*var) = WARNING;
6523         }
6524         else if (pg_strcasecmp(newval, "error") == 0)
6525         {
6526                 if (doit)
6527                         (*var) = ERROR;
6528         }
6529         /* We allow FATAL/PANIC for client-side messages too. */
6530         else if (pg_strcasecmp(newval, "fatal") == 0)
6531         {
6532                 if (doit)
6533                         (*var) = FATAL;
6534         }
6535         else if (pg_strcasecmp(newval, "panic") == 0)
6536         {
6537                 if (doit)
6538                         (*var) = PANIC;
6539         }
6540         else
6541                 return NULL;                    /* fail */
6542         return newval;                          /* OK */
6543 }
6544
6545 static const char *
6546 assign_log_error_verbosity(const char *newval, bool doit, GucSource source)
6547 {
6548         if (pg_strcasecmp(newval, "terse") == 0)
6549         {
6550                 if (doit)
6551                         Log_error_verbosity = PGERROR_TERSE;
6552         }
6553         else if (pg_strcasecmp(newval, "default") == 0)
6554         {
6555                 if (doit)
6556                         Log_error_verbosity = PGERROR_DEFAULT;
6557         }
6558         else if (pg_strcasecmp(newval, "verbose") == 0)
6559         {
6560                 if (doit)
6561                         Log_error_verbosity = PGERROR_VERBOSE;
6562         }
6563         else
6564                 return NULL;                    /* fail */
6565         return newval;                          /* OK */
6566 }
6567
6568 static const char *
6569 assign_log_statement(const char *newval, bool doit, GucSource source)
6570 {
6571         if (pg_strcasecmp(newval, "none") == 0)
6572         {
6573                 if (doit)
6574                         log_statement = LOGSTMT_NONE;
6575         }
6576         else if (pg_strcasecmp(newval, "ddl") == 0)
6577         {
6578                 if (doit)
6579                         log_statement = LOGSTMT_DDL;
6580         }
6581         else if (pg_strcasecmp(newval, "mod") == 0)
6582         {
6583                 if (doit)
6584                         log_statement = LOGSTMT_MOD;
6585         }
6586         else if (pg_strcasecmp(newval, "all") == 0)
6587         {
6588                 if (doit)
6589                         log_statement = LOGSTMT_ALL;
6590         }
6591         else
6592                 return NULL;                    /* fail */
6593         return newval;                          /* OK */
6594 }
6595
6596 static const char *
6597 show_num_temp_buffers(void)
6598 {
6599         /*
6600          * We show the GUC var until local buffers have been initialized, and
6601          * NLocBuffer afterwards.
6602          */
6603         static char nbuf[32];
6604
6605         sprintf(nbuf, "%d", NLocBuffer ? NLocBuffer : num_temp_buffers);
6606         return nbuf;
6607 }
6608
6609 static bool
6610 assign_phony_autocommit(bool newval, bool doit, GucSource source)
6611 {
6612         if (!newval)
6613         {
6614                 if (doit && source >= PGC_S_INTERACTIVE)
6615                         ereport(ERROR,
6616                                         (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
6617                                          errmsg("SET AUTOCOMMIT TO OFF is no longer supported")));
6618                 return false;
6619         }
6620         return true;
6621 }
6622
6623 static const char *
6624 assign_custom_variable_classes(const char *newval, bool doit, GucSource source)
6625 {
6626         /*
6627          * Check syntax. newval must be a comma separated list of identifiers.
6628          * Whitespace is allowed but skipped.
6629          */
6630         bool            hasSpaceAfterToken = false;
6631         const char *cp = newval;
6632         int                     symLen = 0;
6633         int                     c;
6634         StringInfoData buf;
6635
6636         /*
6637          * Resetting custom_variable_classes by removing it from the
6638          * configuration file will lead to newval = NULL
6639          */
6640         if (newval == NULL)
6641                 return guc_strdup(ERROR, "");
6642
6643         initStringInfo(&buf);
6644         while ((c = *cp++) != 0)
6645         {
6646                 if (isspace((unsigned char) c))
6647                 {
6648                         if (symLen > 0)
6649                                 hasSpaceAfterToken = true;
6650                         continue;
6651                 }
6652
6653                 if (c == ',')
6654                 {
6655                         hasSpaceAfterToken = false;
6656                         if (symLen > 0)
6657                         {
6658                                 symLen = 0;
6659                                 appendStringInfoChar(&buf, ',');
6660                         }
6661                         continue;
6662                 }
6663
6664                 if (hasSpaceAfterToken || !isalnum((unsigned char) c))
6665                 {
6666                         /*
6667                          * Syntax error due to token following space after token or non
6668                          * alpha numeric character
6669                          */
6670                         ereport(LOG,
6671                                         (errcode(ERRCODE_SYNTAX_ERROR),
6672                                          errmsg("invalid syntax for \"custom_variable_classes\": \"%s\"", newval)));
6673                         pfree(buf.data);
6674                         return NULL;
6675                 }
6676                 symLen++;
6677                 appendStringInfoChar(&buf, (char) c);
6678         }
6679
6680         /* Remove stray ',' at end */
6681         if (symLen == 0 && buf.len > 0)
6682                 buf.data[--buf.len] = '\0';
6683
6684         if (buf.len == 0)
6685                 newval = NULL;
6686         else if (doit)
6687                 newval = guc_strdup(ERROR, buf.data);
6688
6689         pfree(buf.data);
6690         return newval;
6691 }
6692
6693 static bool
6694 assign_debug_assertions(bool newval, bool doit, GucSource source)
6695 {
6696 #ifndef USE_ASSERT_CHECKING
6697         if (newval)
6698                 ereport(ERROR,
6699                                 (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
6700                            errmsg("assertion checking is not supported by this build")));
6701 #endif
6702         return true;
6703 }
6704
6705 static bool
6706 assign_ssl(bool newval, bool doit, GucSource source)
6707 {
6708 #ifndef USE_SSL
6709         if (newval)
6710                 ereport(ERROR,
6711                                 (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
6712                                  errmsg("SSL is not supported by this build")));
6713 #endif
6714         return true;
6715 }
6716
6717 static bool
6718 assign_stage_log_stats(bool newval, bool doit, GucSource source)
6719 {
6720         if (newval && log_statement_stats)
6721         {
6722                 if (source >= PGC_S_INTERACTIVE)
6723                         ereport(ERROR,
6724                                         (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
6725                                          errmsg("cannot enable parameter when \"log_statement_stats\" is true")));
6726                 /* source == PGC_S_OVERRIDE means do it anyway, eg at xact abort */
6727                 else if (source != PGC_S_OVERRIDE)
6728                         return false;
6729         }
6730         return true;
6731 }
6732
6733 static bool
6734 assign_log_stats(bool newval, bool doit, GucSource source)
6735 {
6736         if (newval &&
6737                 (log_parser_stats || log_planner_stats || log_executor_stats))
6738         {
6739                 if (source >= PGC_S_INTERACTIVE)
6740                         ereport(ERROR,
6741                                         (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
6742                                          errmsg("cannot enable \"log_statement_stats\" when "
6743                                                         "\"log_parser_stats\", \"log_planner_stats\", "
6744                                                         "or \"log_executor_stats\" is true")));
6745                 /* source == PGC_S_OVERRIDE means do it anyway, eg at xact abort */
6746                 else if (source != PGC_S_OVERRIDE)
6747                         return false;
6748         }
6749         return true;
6750 }
6751
6752 static bool
6753 assign_transaction_read_only(bool newval, bool doit, GucSource source)
6754 {
6755         /* Can't go to r/w mode inside a r/o transaction */
6756         if (newval == false && XactReadOnly && IsSubTransaction())
6757         {
6758                 if (source >= PGC_S_INTERACTIVE)
6759                         ereport(ERROR,
6760                                         (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
6761                                          errmsg("cannot set transaction read-write mode inside a read-only transaction")));
6762                 /* source == PGC_S_OVERRIDE means do it anyway, eg at xact abort */
6763                 else if (source != PGC_S_OVERRIDE)
6764                         return false;
6765         }
6766         return true;
6767 }
6768
6769 static const char *
6770 assign_canonical_path(const char *newval, bool doit, GucSource source)
6771 {
6772         if (doit)
6773         {
6774                 char       *canon_val = guc_strdup(ERROR, newval);
6775
6776                 canonicalize_path(canon_val);
6777                 return canon_val;
6778         }
6779         else
6780                 return newval;
6781 }
6782
6783 static const char *
6784 assign_backslash_quote(const char *newval, bool doit, GucSource source)
6785 {
6786         BackslashQuoteType bq;
6787         bool            bqbool;
6788
6789         /*
6790          * Although only "on", "off", and "safe_encoding" are documented, we use
6791          * parse_bool so we can accept all the likely variants of "on" and "off".
6792          */
6793         if (pg_strcasecmp(newval, "safe_encoding") == 0)
6794                 bq = BACKSLASH_QUOTE_SAFE_ENCODING;
6795         else if (parse_bool(newval, &bqbool))
6796         {
6797                 bq = bqbool ? BACKSLASH_QUOTE_ON : BACKSLASH_QUOTE_OFF;
6798         }
6799         else
6800                 return NULL;                    /* reject */
6801
6802         if (doit)
6803                 backslash_quote = bq;
6804
6805         return newval;
6806 }
6807
6808 static const char *
6809 assign_timezone_abbreviations(const char *newval, bool doit, GucSource source)
6810 {
6811         /*
6812          * The powerup value shown above for timezone_abbreviations is "UNKNOWN".
6813          * When we see this we just do nothing.  If this value isn't overridden
6814          * from the config file then pg_timezone_abbrev_initialize() will
6815          * eventually replace it with "Default".  This hack has two purposes: to
6816          * avoid wasting cycles loading values that might soon be overridden from
6817          * the config file, and to avoid trying to read the timezone abbrev files
6818          * during InitializeGUCOptions().  The latter doesn't work in an
6819          * EXEC_BACKEND subprocess because my_exec_path hasn't been set yet and so
6820          * we can't locate PGSHAREDIR.  (Essentially the same hack is used to
6821          * delay initializing TimeZone ... if we have any more, we should try to
6822          * clean up and centralize this mechanism ...)
6823          */
6824         if (strcmp(newval, "UNKNOWN") == 0)
6825         {
6826                 return newval;
6827         }
6828
6829         /* Loading abbrev file is expensive, so only do it when value changes */
6830         if (timezone_abbreviations_string == NULL ||
6831                 strcmp(timezone_abbreviations_string, newval) != 0)
6832         {
6833                 int                     elevel;
6834
6835                 /*
6836                  * If reading config file, only the postmaster should bleat loudly
6837                  * about problems.      Otherwise, it's just this one process doing it,
6838                  * and we use WARNING message level.
6839                  */
6840                 if (source == PGC_S_FILE)
6841                         elevel = IsUnderPostmaster ? DEBUG2 : LOG;
6842                 else
6843                         elevel = WARNING;
6844                 if (!load_tzoffsets(newval, doit, elevel))
6845                         return NULL;
6846         }
6847         return newval;
6848 }
6849
6850 /*
6851  * pg_timezone_abbrev_initialize --- set default value if not done already
6852  *
6853  * This is called after initial loading of postgresql.conf.  If no
6854  * timezone_abbreviations setting was found therein, select default.
6855  */
6856 void
6857 pg_timezone_abbrev_initialize(void)
6858 {
6859         if (strcmp(timezone_abbreviations_string, "UNKNOWN") == 0)
6860         {
6861                 SetConfigOption("timezone_abbreviations", "Default",
6862                                                 PGC_POSTMASTER, PGC_S_ARGV);
6863         }
6864 }
6865
6866 static const char *
6867 assign_xmlbinary(const char *newval, bool doit, GucSource source)
6868 {
6869         XmlBinaryType xb;
6870
6871         if (pg_strcasecmp(newval, "base64") == 0)
6872                 xb = XMLBINARY_BASE64;
6873         else if (pg_strcasecmp(newval, "hex") == 0)
6874                 xb = XMLBINARY_HEX;
6875         else
6876                 return NULL;                    /* reject */
6877
6878         if (doit)
6879                 xmlbinary = xb;
6880
6881         return newval;
6882 }
6883
6884 static const char *
6885 assign_xmloption(const char *newval, bool doit, GucSource source)
6886 {
6887         XmlOptionType xo;
6888
6889         if (pg_strcasecmp(newval, "document") == 0)
6890                 xo = XMLOPTION_DOCUMENT;
6891         else if (pg_strcasecmp(newval, "content") == 0)
6892                 xo = XMLOPTION_CONTENT;
6893         else
6894                 return NULL;                    /* reject */
6895
6896         if (doit)
6897                 xmloption = xo;
6898
6899         return newval;
6900 }
6901
6902 static bool
6903 assign_tcp_keepalives_idle(int newval, bool doit, GucSource source)
6904 {
6905         if (doit)
6906                 return (pq_setkeepalivesidle(newval, MyProcPort) == STATUS_OK);
6907
6908         return true;
6909 }
6910
6911 static const char *
6912 show_tcp_keepalives_idle(void)
6913 {
6914         static char nbuf[16];
6915
6916         snprintf(nbuf, sizeof(nbuf), "%d", pq_getkeepalivesidle(MyProcPort));
6917         return nbuf;
6918 }
6919
6920 static bool
6921 assign_tcp_keepalives_interval(int newval, bool doit, GucSource source)
6922 {
6923         if (doit)
6924                 return (pq_setkeepalivesinterval(newval, MyProcPort) == STATUS_OK);
6925
6926         return true;
6927 }
6928
6929 static const char *
6930 show_tcp_keepalives_interval(void)
6931 {
6932         static char nbuf[16];
6933
6934         snprintf(nbuf, sizeof(nbuf), "%d", pq_getkeepalivesinterval(MyProcPort));
6935         return nbuf;
6936 }
6937
6938 static bool
6939 assign_tcp_keepalives_count(int newval, bool doit, GucSource source)
6940 {
6941         if (doit)
6942                 return (pq_setkeepalivescount(newval, MyProcPort) == STATUS_OK);
6943
6944         return true;
6945 }
6946
6947 static const char *
6948 show_tcp_keepalives_count(void)
6949 {
6950         static char nbuf[16];
6951
6952         snprintf(nbuf, sizeof(nbuf), "%d", pq_getkeepalivescount(MyProcPort));
6953         return nbuf;
6954 }
6955
6956 static bool
6957 assign_maxconnections(int newval, bool doit, GucSource source)
6958 {
6959         if (newval + autovacuum_max_workers > INT_MAX / 4)
6960                 return false;
6961
6962         if (doit)
6963                 MaxBackends = newval + autovacuum_max_workers;
6964
6965         return true;
6966 }
6967
6968 static bool
6969 assign_autovacuum_max_workers(int newval, bool doit, GucSource source)
6970 {
6971         if (newval + MaxConnections > INT_MAX / 4)
6972                 return false;
6973
6974         if (doit)
6975                 MaxBackends = newval + MaxConnections;
6976
6977         return true;
6978 }
6979
6980 #include "guc-file.c"