X-Git-Url: https://granicus.if.org/sourcecode?a=blobdiff_plain;f=src%2Fbackend%2Futils%2Fmisc%2Fguc.c;h=38d577f87bb9a892a8908bc8f7d3dcc2eafe02bb;hb=901be0fad4034c9cf8a3588fd6cf2ece82e4b8ce;hp=00dac28c27e14f32d89ad0790694cc2bd0140e25;hpb=c98c9114cb3bff8a493333ef48d16eb55601af54;p=postgresql

diff --git a/src/backend/utils/misc/guc.c b/src/backend/utils/misc/guc.c
index 00dac28c27..38d577f87b 100644
--- a/src/backend/utils/misc/guc.c
+++ b/src/backend/utils/misc/guc.c
@@ -6,11 +6,11 @@
  * See src/backend/utils/misc/README for more information.
  *
  *
- * Copyright (c) 2000-2008, PostgreSQL Global Development Group
+ * Copyright (c) 2000-2010, PostgreSQL Global Development Group
  * Written by Peter Eisentraut <peter_e@gmx.net>.
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/utils/misc/guc.c,v 1.482 2008/12/02 02:00:32 alvherre Exp $
+ *	  $PostgreSQL: pgsql/src/backend/utils/misc/guc.c,v 1.532 2010/01/07 04:53:35 tgl Exp $
  *
  *--------------------------------------------------------------------
  */
@@ -18,6 +18,7 @@
 
 #include <ctype.h>
 #include <float.h>
+#include <math.h>
 #include <limits.h>
 #include <unistd.h>
 #include <sys/stat.h>
@@ -37,16 +38,16 @@
 #include "commands/trigger.h"
 #include "funcapi.h"
 #include "libpq/auth.h"
+#include "libpq/be-fsstubs.h"
 #include "libpq/pqformat.h"
 #include "miscadmin.h"
 #include "optimizer/cost.h"
 #include "optimizer/geqo.h"
 #include "optimizer/paths.h"
 #include "optimizer/planmain.h"
-#include "parser/gramparse.h"
 #include "parser/parse_expr.h"
-#include "parser/parse_relation.h"
 #include "parser/parse_type.h"
+#include "parser/parser.h"
 #include "parser/scansup.h"
 #include "pgstat.h"
 #include "postmaster/autovacuum.h"
@@ -54,12 +55,12 @@
 #include "postmaster/postmaster.h"
 #include "postmaster/syslogger.h"
 #include "postmaster/walwriter.h"
-#include "regex/regex.h"
 #include "storage/bufmgr.h"
 #include "storage/fd.h"
 #include "tcop/tcopprot.h"
 #include "tsearch/ts_cache.h"
 #include "utils/builtins.h"
+#include "utils/bytea.h"
 #include "utils/guc_tables.h"
 #include "utils/memutils.h"
 #include "utils/pg_locale.h"
@@ -86,7 +87,8 @@
 #endif
 
 /* upper limit for GUC variables measured in kilobytes of memory */
-#if SIZEOF_SIZE_T > 4
+/* note that various places assume the byte size fits in a "long" variable */
+#if SIZEOF_SIZE_T > 4 && SIZEOF_LONG > 4
 #define MAX_KILOBYTES	INT_MAX
 #else
 #define MAX_KILOBYTES	(INT_MAX / 1024)
@@ -113,6 +115,9 @@ extern char *default_tablespace;
 extern char *temp_tablespaces;
 extern bool synchronize_seqscans;
 extern bool fullPageWrites;
+extern int	vacuum_defer_cleanup_age;
+
+int	trace_recovery_messages = LOG;
 
 #ifdef TRACE_SORT
 extern bool trace_sort;
@@ -138,7 +143,7 @@ static const char *assign_log_destination(const char *value,
 static int	syslog_facility = LOG_LOCAL0;
 
 static bool assign_syslog_facility(int newval,
-				    bool doit, GucSource source);
+					   bool doit, GucSource source);
 static const char *assign_syslog_ident(const char *ident,
 					bool doit, GucSource source);
 #endif
@@ -150,6 +155,7 @@ static bool assign_phony_autocommit(bool newval, bool doit, GucSource source);
 static const char *assign_custom_variable_classes(const char *newval, bool doit,
 							   GucSource source);
 static bool assign_debug_assertions(bool newval, bool doit, GucSource source);
+static bool assign_bonjour(bool newval, bool doit, GucSource source);
 static bool assign_ssl(bool newval, bool doit, GucSource source);
 static bool assign_stage_log_stats(bool newval, bool doit, GucSource source);
 static bool assign_log_stats(bool newval, bool doit, GucSource source);
@@ -163,13 +169,15 @@ static bool assign_tcp_keepalives_count(int newval, bool doit, GucSource source)
 static const char *show_tcp_keepalives_idle(void);
 static const char *show_tcp_keepalives_interval(void);
 static const char *show_tcp_keepalives_count(void);
-static bool assign_autovacuum_max_workers(int newval, bool doit, GucSource source);
 static bool assign_maxconnections(int newval, bool doit, GucSource source);
+static bool assign_autovacuum_max_workers(int newval, bool doit, GucSource source);
+static bool assign_effective_io_concurrency(int newval, bool doit, GucSource source);
 static const char *assign_pgstat_temp_directory(const char *newval, bool doit, GucSource source);
+static const char *assign_application_name(const char *newval, bool doit, GucSource source);
 
-static char *config_enum_get_options(struct config_enum *record, 
-									 const char *prefix, const char *suffix,
-									 const char *separator);
+static char *config_enum_get_options(struct config_enum * record,
+						const char *prefix, const char *suffix,
+						const char *separator);
 
 
 /*
@@ -178,6 +186,12 @@ static char *config_enum_get_options(struct config_enum *record,
  * NOTE! Option values may not contain double quotes!
  */
 
+static const struct config_enum_entry bytea_output_options[] = {
+	{"escape", BYTEA_OUTPUT_ESCAPE, false},
+	{"hex", BYTEA_OUTPUT_HEX, false},
+	{NULL, 0, false}
+};
+
 /*
  * We have different sets for client and server message level options because
  * they sort slightly different (see "log" level)
@@ -239,13 +253,6 @@ static const struct config_enum_entry log_statement_options[] = {
 	{NULL, 0, false}
 };
 
-static const struct config_enum_entry regex_flavor_options[] = {
-    {"advanced", REG_ADVANCED, false},
-    {"extended", REG_EXTENDED, false},
-    {"basic", REG_BASIC, false},
-    {NULL, 0, false}
-};
-
 static const struct config_enum_entry isolation_level_options[] = {
 	{"serializable", XACT_SERIALIZABLE, false},
 	{"repeatable read", XACT_REPEATABLE_READ, false},
@@ -311,6 +318,23 @@ static const struct config_enum_entry backslash_quote_options[] = {
 	{NULL, 0, false}
 };
 
+/*
+ * Although only "on", "off", and "partition" are documented, we
+ * accept all the likely variants of "on" and "off".
+ */
+static const struct config_enum_entry constraint_exclusion_options[] = {
+	{"partition", CONSTRAINT_EXCLUSION_PARTITION, false},
+	{"on", CONSTRAINT_EXCLUSION_ON, false},
+	{"off", CONSTRAINT_EXCLUSION_OFF, false},
+	{"true", CONSTRAINT_EXCLUSION_ON, true},
+	{"false", CONSTRAINT_EXCLUSION_OFF, true},
+	{"yes", CONSTRAINT_EXCLUSION_ON, true},
+	{"no", CONSTRAINT_EXCLUSION_OFF, true},
+	{"1", CONSTRAINT_EXCLUSION_ON, true},
+	{"0", CONSTRAINT_EXCLUSION_OFF, true},
+	{NULL, 0, false}
+};
+
 /*
  * Options for enum values stored in other modules
  */
@@ -358,6 +382,10 @@ char	   *external_pid_file;
 
 char	   *pgstat_temp_directory;
 
+char	   *default_do_language;
+
+char	   *application_name;
+
 int			tcp_keepalives_idle;
 int			tcp_keepalives_interval;
 int			tcp_keepalives_count;
@@ -396,6 +424,7 @@ static int	segment_size;
 static int	wal_block_size;
 static int	wal_segment_size;
 static bool integer_datetimes;
+static int	effective_io_concurrency;
 
 /* should be static, but commands/variable.c needs to get at these */
 char	   *role_string;
@@ -430,6 +459,7 @@ const char *const GucSource_Names[] =
 	 /* PGC_S_ARGV */ "command line",
 	 /* PGC_S_DATABASE */ "database",
 	 /* PGC_S_USER */ "user",
+	 /* PGC_S_DATABASE_USER */ "database user",
 	 /* PGC_S_CLIENT */ "client",
 	 /* PGC_S_OVERRIDE */ "override",
 	 /* PGC_S_INTERACTIVE */ "interactive",
@@ -635,15 +665,6 @@ static struct config_bool ConfigureNamesBool[] =
 		&enable_hashjoin,
 		true, NULL, NULL
 	},
-	{
-		{"constraint_exclusion", PGC_USERSET, QUERY_TUNING_OTHER,
-			gettext_noop("Enables the planner to use constraints to optimize queries."),
-			gettext_noop("Child table scans will be skipped if their "
-					   "constraints guarantee that no rows match the query.")
-		},
-		&constraint_exclusion,
-		false, NULL, NULL
-	},
 	{
 		{"geqo", PGC_USERSET, QUERY_TUNING_GEQO,
 			gettext_noop("Enables genetic query optimization."),
@@ -663,6 +684,14 @@ static struct config_bool ConfigureNamesBool[] =
 		&session_auth_is_superuser,
 		false, NULL, NULL
 	},
+	{
+		{"bonjour", PGC_POSTMASTER, CONN_AUTH_SETTINGS,
+			gettext_noop("Enables advertising the server via Bonjour."),
+			NULL
+		},
+		&enable_bonjour,
+		false, assign_bonjour, NULL
+	},
 	{
 		{"ssl", PGC_POSTMASTER, CONN_AUTH_SECURITY,
 			gettext_noop("Enables SSL connections."),
@@ -716,7 +745,7 @@ static struct config_bool ConfigureNamesBool[] =
 		true, NULL, NULL
 	},
 	{
-		{"silent_mode", PGC_POSTMASTER, LOGGING_WHEN,
+		{"silent_mode", PGC_POSTMASTER, LOGGING_WHERE,
 			gettext_noop("Runs the server silently."),
 			gettext_noop("If this parameter is set, the server will automatically run in the "
 				 "background and any controlling terminals are dissociated.")
@@ -1027,14 +1056,6 @@ static struct config_bool ConfigureNamesBool[] =
 		&XactReadOnly,
 		false, assign_transaction_read_only, NULL
 	},
-	{
-		{"add_missing_from", PGC_USERSET, COMPAT_OPTIONS_PREVIOUS,
-			gettext_noop("Automatically adds missing table references to FROM clauses."),
-			NULL
-		},
-		&add_missing_from,
-		false, NULL, NULL
-	},
 	{
 		{"check_function_bodies", PGC_USERSET, CLIENT_CONN_STATEMENT,
 			gettext_noop("Check function bodies during CREATE FUNCTION."),
@@ -1144,7 +1165,7 @@ static struct config_bool ConfigureNamesBool[] =
 	},
 
 	{
-		{"krb_caseins_users", PGC_POSTMASTER, CONN_AUTH_SECURITY,
+		{"krb_caseins_users", PGC_SIGHUP, CONN_AUTH_SECURITY,
 			gettext_noop("Sets whether Kerberos and GSSAPI user names should be treated as case-insensitive."),
 			NULL
 		},
@@ -1189,6 +1210,17 @@ static struct config_bool ConfigureNamesBool[] =
 		false, NULL, NULL
 	},
 
+	{
+		{"recovery_connections", PGC_POSTMASTER, WAL_SETTINGS,
+			gettext_noop("During recovery, allows connections and queries. "
+						 " During normal running, causes additional info to be written"
+						 " to WAL to enable hot standby mode on WAL standby nodes."),
+			NULL
+		},
+		&XLogRequestRecoveryConnections,
+		true, NULL, NULL
+	},
+
 	{
 		{"allow_system_table_mods", PGC_POSTMASTER, DEVELOPER_OPTIONS,
 			gettext_noop("Allows modifications of the structure of system tables."),
@@ -1210,6 +1242,16 @@ static struct config_bool ConfigureNamesBool[] =
 		false, NULL, NULL
 	},
 
+	{
+		{"lo_compat_privileges", PGC_SUSET, COMPAT_OPTIONS_PREVIOUS,
+			gettext_noop("Enables backward compatibility mode for privilege checks on large objects"),
+			gettext_noop("Skips privilege checks when reading or modifying large objects, "
+						 "for compatibility with PostgreSQL releases prior to 8.5.")
+		},
+		&lo_compat_privileges,
+		false, NULL, NULL
+	},
+
 	/* End-of-list marker */
 	{
 		{NULL, 0, 0, NULL, NULL}, NULL, false, NULL, NULL
@@ -1245,7 +1287,7 @@ static struct config_int ConfigureNamesInt[] =
 				"column-specific target set via ALTER TABLE SET STATISTICS.")
 		},
 		&default_statistics_target,
-		10, 1, 1000, NULL, NULL
+		100, 1, 10000, NULL, NULL
 	},
 	{
 		{"from_collapse_limit", PGC_USERSET, QUERY_TUNING_OTHER,
@@ -1317,9 +1359,11 @@ static struct config_int ConfigureNamesInt[] =
 	 * Note: MaxBackends is limited to INT_MAX/4 because some places compute
 	 * 4*MaxBackends without any overflow check.  This check is made in
 	 * assign_maxconnections, since MaxBackends is computed as MaxConnections
-	 * plus autovacuum_max_workers.
+	 * plus autovacuum_max_workers plus one (for the autovacuum launcher).
 	 *
 	 * Likewise we have to limit NBuffers to INT_MAX/2.
+	 *
+	 * See also CheckRequiredParameterValues() if this parameter changes
 	 */
 	{
 		{"max_connections", PGC_POSTMASTER, CONN_AUTH_SETTINGS,
@@ -1330,6 +1374,15 @@ static struct config_int ConfigureNamesInt[] =
 		100, 1, INT_MAX / 4, assign_maxconnections, NULL
 	},
 
+	{
+		{"max_standby_delay", PGC_SIGHUP, WAL_SETTINGS,
+			gettext_noop("Sets the maximum delay to avoid conflict processing on Hot Standby servers."),
+			NULL
+		},
+		&MaxStandbyDelay,
+		30, -1, INT_MAX, NULL, NULL
+	},
+
 	{
 		{"superuser_reserved_connections", PGC_POSTMASTER, CONN_AUTH_SETTINGS,
 			gettext_noop("Sets the number of connection slots reserved for superusers."),
@@ -1456,7 +1509,7 @@ static struct config_int ConfigureNamesInt[] =
 			GUC_UNIT_MS
 		},
 		&VacuumCostDelay,
-		0, 0, 1000, NULL, NULL
+		0, 0, 100, NULL, NULL
 	},
 
 	{
@@ -1466,7 +1519,7 @@ static struct config_int ConfigureNamesInt[] =
 			GUC_UNIT_MS
 		},
 		&autovacuum_vac_cost_delay,
-		20, -1, 1000, NULL, NULL
+		20, -1, 100, NULL, NULL
 	},
 
 	{
@@ -1487,13 +1540,16 @@ static struct config_int ConfigureNamesInt[] =
 		1000, 25, INT_MAX, NULL, NULL
 	},
 
+	/*
+	 * See also CheckRequiredParameterValues() if this parameter changes
+	 */
 	{
 		{"max_prepared_transactions", PGC_POSTMASTER, RESOURCES,
 			gettext_noop("Sets the maximum number of simultaneously prepared transactions."),
 			NULL
 		},
 		&max_prepared_xacts,
-		5, 0, INT_MAX, NULL, NULL
+		0, 0, INT_MAX / 4, NULL, NULL
 	},
 
 #ifdef LOCK_DEBUG
@@ -1533,9 +1589,30 @@ static struct config_int ConfigureNamesInt[] =
 			NULL
 		},
 		&vacuum_freeze_min_age,
-		100000000, 0, 1000000000, NULL, NULL
+		50000000, 0, 1000000000, NULL, NULL
+	},
+
+	{
+		{"vacuum_freeze_table_age", PGC_USERSET, CLIENT_CONN_STATEMENT,
+			gettext_noop("Age at which VACUUM should scan whole table to freeze tuples."),
+			NULL
+		},
+		&vacuum_freeze_table_age,
+		150000000, 0, 2000000000, NULL, NULL
+	},
+
+	{
+		{"vacuum_defer_cleanup_age", PGC_USERSET, CLIENT_CONN_STATEMENT,
+			gettext_noop("Age by which VACUUM and HOT cleanup should be deferred, if any."),
+			NULL
+		},
+		&vacuum_defer_cleanup_age,
+		0, 0, 1000000, NULL, NULL
 	},
 
+	/*
+	 * See also CheckRequiredParameterValues() if this parameter changes
+	 */
 	{
 		{"max_locks_per_transaction", PGC_POSTMASTER, LOCK_MANAGEMENT,
 			gettext_noop("Sets the maximum number of locks per transaction."),
@@ -1648,7 +1725,7 @@ static struct config_int ConfigureNamesInt[] =
 						 "(FLT_DIG or DBL_DIG as appropriate).")
 		},
 		&extra_float_digits,
-		0, -15, 2, NULL, NULL
+		0, -15, 3, NULL, NULL
 	},
 
 	{
@@ -1692,6 +1769,26 @@ static struct config_int ConfigureNamesInt[] =
 		100, 0, 1000, NULL, NULL
 	},
 
+	{
+		{"effective_io_concurrency",
+#ifdef USE_PREFETCH
+			PGC_USERSET,
+#else
+			PGC_INTERNAL,
+#endif
+			RESOURCES,
+			gettext_noop("Number of simultaneous requests that can be handled efficiently by the disk subsystem."),
+			gettext_noop("For RAID arrays, this should be approximately the number of drive spindles in the array.")
+		},
+		&effective_io_concurrency,
+#ifdef USE_PREFETCH
+		1, 0, 1000,
+#else
+		0, 0, 0,
+#endif
+		assign_effective_io_concurrency, NULL
+	},
+
 	{
 		{"log_rotation_age", PGC_SIGHUP, LOGGING_WHERE,
 			gettext_noop("Automatic log file rotation will occur after N minutes."),
@@ -1754,9 +1851,9 @@ static struct config_int ConfigureNamesInt[] =
 
 	{
 		{"segment_size", PGC_INTERNAL, PRESET_OPTIONS,
-		    gettext_noop("Shows the number of pages per disk file."),
-		    NULL,
-		    GUC_UNIT_BLOCKS | GUC_NOT_IN_SAMPLE | GUC_DISALLOW_IN_FILE
+			gettext_noop("Shows the number of pages per disk file."),
+			NULL,
+			GUC_UNIT_BLOCKS | GUC_NOT_IN_SAMPLE | GUC_DISALLOW_IN_FILE
 		},
 		&segment_size,
 		RELSEG_SIZE, RELSEG_SIZE, RELSEG_SIZE, NULL, NULL
@@ -1779,8 +1876,8 @@ static struct config_int ConfigureNamesInt[] =
 			GUC_UNIT_XBLOCKS | GUC_NOT_IN_SAMPLE | GUC_DISALLOW_IN_FILE
 		},
 		&wal_segment_size,
-		(XLOG_SEG_SIZE / XLOG_BLCKSZ), 
-		(XLOG_SEG_SIZE / XLOG_BLCKSZ), 
+		(XLOG_SEG_SIZE / XLOG_BLCKSZ),
+		(XLOG_SEG_SIZE / XLOG_BLCKSZ),
 		(XLOG_SEG_SIZE / XLOG_BLCKSZ),
 		NULL, NULL
 	},
@@ -1817,6 +1914,7 @@ static struct config_int ConfigureNamesInt[] =
 			NULL
 		},
 		&autovacuum_freeze_max_age,
+		/* see pg_resetxlog if you change the upper-limit value */
 		200000000, 100000000, 2000000000, NULL, NULL
 	},
 	{
@@ -1986,6 +2084,14 @@ static struct config_real ConfigureNamesReal[] =
 		DEFAULT_GEQO_SELECTION_BIAS, MIN_GEQO_SELECTION_BIAS,
 		MAX_GEQO_SELECTION_BIAS, NULL, NULL
 	},
+	{
+		{"geqo_seed", PGC_USERSET, QUERY_TUNING_GEQO,
+			gettext_noop("GEQO: seed for random path selection."),
+			NULL
+		},
+		&Geqo_seed,
+		0.0, 0.0, 1.0, NULL, NULL
+	},
 
 	{
 		{"bgwriter_lru_multiplier", PGC_SIGHUP, RESOURCES,
@@ -2123,17 +2229,7 @@ static struct config_string ConfigureNamesString[] =
 	},
 
 	{
-		{"krb_realm", PGC_POSTMASTER, CONN_AUTH_SECURITY,
-			gettext_noop("Sets realm to match Kerberos and GSSAPI users against."),
-			NULL,
-			GUC_SUPERUSER_ONLY
-		},
-		&pg_krb_realm,
-		NULL, NULL, NULL
-	},
-
-	{
-		{"krb_server_keyfile", PGC_POSTMASTER, CONN_AUTH_SECURITY,
+		{"krb_server_keyfile", PGC_SIGHUP, CONN_AUTH_SECURITY,
 			gettext_noop("Sets the location of the Kerberos server key file."),
 			NULL,
 			GUC_SUPERUSER_ONLY
@@ -2143,7 +2239,7 @@ static struct config_string ConfigureNamesString[] =
 	},
 
 	{
-		{"krb_srvname", PGC_POSTMASTER, CONN_AUTH_SECURITY,
+		{"krb_srvname", PGC_SIGHUP, CONN_AUTH_SECURITY,
 			gettext_noop("Sets the name of the Kerberos service."),
 			NULL
 		},
@@ -2151,18 +2247,9 @@ static struct config_string ConfigureNamesString[] =
 		PG_KRB_SRVNAM, NULL, NULL
 	},
 
-	{
-		{"krb_server_hostname", PGC_POSTMASTER, CONN_AUTH_SECURITY,
-			gettext_noop("Sets the hostname of the Kerberos server."),
-			NULL
-		},
-		&pg_krb_server_hostname,
-		NULL, NULL, NULL
-	},
-
 	{
 		{"bonjour_name", PGC_POSTMASTER, CONN_AUTH_SETTINGS,
-			gettext_noop("Sets the Bonjour broadcast service name."),
+			gettext_noop("Sets the Bonjour service name."),
 			NULL
 		},
 		&bonjour_name,
@@ -2284,7 +2371,7 @@ static struct config_string ConfigureNamesString[] =
 		{"role", PGC_USERSET, UNGROUPED,
 			gettext_noop("Sets the current role."),
 			NULL,
-			GUC_IS_NAME | GUC_NO_SHOW_ALL | GUC_NO_RESET_ALL | GUC_NOT_IN_SAMPLE | GUC_DISALLOW_IN_FILE
+			GUC_IS_NAME | GUC_NO_SHOW_ALL | GUC_NO_RESET_ALL | GUC_NOT_IN_SAMPLE | GUC_DISALLOW_IN_FILE | GUC_NOT_WHILE_SEC_REST
 		},
 		&role_string,
 		"none", assign_role, show_role
@@ -2295,7 +2382,7 @@ static struct config_string ConfigureNamesString[] =
 		{"session_authorization", PGC_USERSET, UNGROUPED,
 			gettext_noop("Sets the session user name."),
 			NULL,
-			GUC_IS_NAME | GUC_REPORT | GUC_NO_SHOW_ALL | GUC_NO_RESET_ALL | GUC_NOT_IN_SAMPLE | GUC_DISALLOW_IN_FILE
+			GUC_IS_NAME | GUC_REPORT | GUC_NO_SHOW_ALL | GUC_NO_RESET_ALL | GUC_NOT_IN_SAMPLE | GUC_DISALLOW_IN_FILE | GUC_NOT_WHILE_SEC_REST
 		},
 		&session_authorization_string,
 		NULL, assign_session_authorization, show_session_authorization
@@ -2493,6 +2580,25 @@ static struct config_string ConfigureNamesString[] =
 	},
 #endif   /* USE_SSL */
 
+	{
+		{"default_do_language", PGC_USERSET, CLIENT_CONN_STATEMENT,
+			gettext_noop("Sets the language used in DO statement if LANGUAGE is not specified."),
+			NULL
+		},
+		&default_do_language,
+		"plpgsql", NULL, NULL
+	},
+
+	{
+		{"application_name", PGC_USERSET, LOGGING,
+		 gettext_noop("Sets the application name to be reported in statistics and logs."),
+		 NULL,
+		 GUC_IS_NAME | GUC_REPORT | GUC_NOT_IN_SAMPLE
+		},
+		&application_name,
+		"", assign_application_name, NULL
+	},
+
 	/* End-of-list marker */
 	{
 		{NULL, 0, 0, NULL, NULL}, NULL, NULL, NULL, NULL
@@ -2511,6 +2617,15 @@ static struct config_enum ConfigureNamesEnum[] =
 		BACKSLASH_QUOTE_SAFE_ENCODING, backslash_quote_options, NULL, NULL
 	},
 
+	{
+		{"bytea_output", PGC_USERSET, CLIENT_CONN_STATEMENT,
+			gettext_noop("Sets the output format for bytea."),
+			NULL
+		},
+		&bytea_output,
+		BYTEA_OUTPUT_HEX, bytea_output_options, NULL, NULL
+	},
+
 	{
 		{"client_min_messages", PGC_USERSET, LOGGING_WHEN,
 			gettext_noop("Sets the message levels that are sent to the client."),
@@ -2521,6 +2636,17 @@ static struct config_enum ConfigureNamesEnum[] =
 		NOTICE, client_message_level_options, NULL, NULL
 	},
 
+	{
+		{"constraint_exclusion", PGC_USERSET, QUERY_TUNING_OTHER,
+			gettext_noop("Enables the planner to use constraints to optimize queries."),
+			gettext_noop("Table scans will be skipped if their constraints"
+						 " guarantee that no rows match the query.")
+		},
+		&constraint_exclusion,
+		CONSTRAINT_EXCLUSION_PARTITION, constraint_exclusion_options,
+		NULL, NULL
+	},
+
 	{
 		{"default_transaction_isolation", PGC_USERSET, CLIENT_CONN_STATEMENT,
 			gettext_noop("Sets the transaction isolation level of each new transaction."),
@@ -2530,7 +2656,7 @@ static struct config_enum ConfigureNamesEnum[] =
 		XACT_READ_COMMITTED, isolation_level_options, NULL, NULL
 	},
 
- 	{
+	{
 		{"IntervalStyle", PGC_USERSET, CLIENT_CONN_LOCALE,
 			gettext_noop("Sets the display format for interval values."),
 			NULL,
@@ -2589,15 +2715,6 @@ static struct config_enum ConfigureNamesEnum[] =
 	},
 #endif
 
-	{
-		{"regex_flavor", PGC_USERSET, COMPAT_OPTIONS_PREVIOUS,
-			gettext_noop("Sets the regular expression \"flavor\"."),
-			NULL
-		},
-		&regex_flavor,
-		REG_ADVANCED, regex_flavor_options, NULL, NULL
-	},
-
 	{
 		{"session_replication_role", PGC_SUSET, CLIENT_CONN_STATEMENT,
 			gettext_noop("Sets the session's behavior for triggers and rewrite rules."),
@@ -2608,6 +2725,16 @@ static struct config_enum ConfigureNamesEnum[] =
 		assign_session_replication_role, NULL
 	},
 
+	{
+		{"trace_recovery_messages", PGC_SUSET, LOGGING_WHEN,
+			gettext_noop("Sets the message levels that are logged during recovery."),
+			gettext_noop("Each level includes all the levels that follow it. The later"
+						 " the level, the fewer messages are sent.")
+		},
+		&trace_recovery_messages,
+		DEBUG1, server_message_level_options, NULL, NULL
+	},
+
 	{
 		{"track_functions", PGC_SUSET, STATS_COLLECTOR,
 			gettext_noop("Collects function-level statistics on database activity."),
@@ -2623,7 +2750,7 @@ static struct config_enum ConfigureNamesEnum[] =
 			NULL
 		},
 		&sync_method,
-		DEFAULT_SYNC_METHOD, sync_method_options, 
+		DEFAULT_SYNC_METHOD, sync_method_options,
 		assign_xlog_sync_method, NULL
 	},
 
@@ -2690,7 +2817,7 @@ static int	GUCNestLevel = 0;	/* 1 when in main transaction */
 
 static int	guc_var_compare(const void *a, const void *b);
 static int	guc_name_compare(const char *namea, const char *nameb);
-static void InitializeOneGUCOption(struct config_generic *gconf);
+static void InitializeOneGUCOption(struct config_generic * gconf);
 static void push_old_value(struct config_generic * gconf, GucAction action);
 static void ReportGUCOption(struct config_generic * record);
 static void ShowGUCConfigOption(const char *name, DestReceiver *dest);
@@ -2821,7 +2948,7 @@ set_stack_value(struct config_generic * gconf, union config_var_value * val)
 							 *((struct config_string *) gconf)->variable);
 			break;
 		case PGC_ENUM:
-			val->enumval = 
+			val->enumval =
 				*((struct config_enum *) gconf)->variable;
 			break;
 	}
@@ -3258,7 +3385,7 @@ InitializeGUCOptions(void)
  * Initialize one GUC option variable to its compiled-in default.
  */
 static void
-InitializeOneGUCOption(struct config_generic *gconf)
+InitializeOneGUCOption(struct config_generic * gconf)
 {
 	gconf->status = 0;
 	gconf->reset_source = PGC_S_DEFAULT;
@@ -3270,100 +3397,100 @@ InitializeOneGUCOption(struct config_generic *gconf)
 	switch (gconf->vartype)
 	{
 		case PGC_BOOL:
-		{
-			struct config_bool *conf = (struct config_bool *) gconf;
-
-			if (conf->assign_hook)
-				if (!(*conf->assign_hook) (conf->boot_val, true,
-										   PGC_S_DEFAULT))
-					elog(FATAL, "failed to initialize %s to %d",
-						 conf->gen.name, (int) conf->boot_val);
-			*conf->variable = conf->reset_val = conf->boot_val;
-			break;
-		}
-		case PGC_INT:
-		{
-			struct config_int *conf = (struct config_int *) gconf;
-
-			Assert(conf->boot_val >= conf->min);
-			Assert(conf->boot_val <= conf->max);
-			if (conf->assign_hook)
-				if (!(*conf->assign_hook) (conf->boot_val, true,
-										   PGC_S_DEFAULT))
-					elog(FATAL, "failed to initialize %s to %d",
-						 conf->gen.name, conf->boot_val);
-			*conf->variable = conf->reset_val = conf->boot_val;
-			break;
-		}
-		case PGC_REAL:
-		{
-			struct config_real *conf = (struct config_real *) gconf;
-
-			Assert(conf->boot_val >= conf->min);
-			Assert(conf->boot_val <= conf->max);
-			if (conf->assign_hook)
-				if (!(*conf->assign_hook) (conf->boot_val, true,
-										   PGC_S_DEFAULT))
-					elog(FATAL, "failed to initialize %s to %g",
-						 conf->gen.name, conf->boot_val);
-			*conf->variable = conf->reset_val = conf->boot_val;
-			break;
-		}
-		case PGC_STRING:
-		{
-			struct config_string *conf = (struct config_string *) gconf;
-			char	   *str;
-
-			*conf->variable = NULL;
-			conf->reset_val = NULL;
-
-			if (conf->boot_val == NULL)
 			{
-				/* leave the value NULL, do not call assign hook */
+				struct config_bool *conf = (struct config_bool *) gconf;
+
+				if (conf->assign_hook)
+					if (!(*conf->assign_hook) (conf->boot_val, true,
+											   PGC_S_DEFAULT))
+						elog(FATAL, "failed to initialize %s to %d",
+							 conf->gen.name, (int) conf->boot_val);
+				*conf->variable = conf->reset_val = conf->boot_val;
 				break;
 			}
+		case PGC_INT:
+			{
+				struct config_int *conf = (struct config_int *) gconf;
 
-			str = guc_strdup(FATAL, conf->boot_val);
-			conf->reset_val = str;
+				Assert(conf->boot_val >= conf->min);
+				Assert(conf->boot_val <= conf->max);
+				if (conf->assign_hook)
+					if (!(*conf->assign_hook) (conf->boot_val, true,
+											   PGC_S_DEFAULT))
+						elog(FATAL, "failed to initialize %s to %d",
+							 conf->gen.name, conf->boot_val);
+				*conf->variable = conf->reset_val = conf->boot_val;
+				break;
+			}
+		case PGC_REAL:
+			{
+				struct config_real *conf = (struct config_real *) gconf;
 
-			if (conf->assign_hook)
+				Assert(conf->boot_val >= conf->min);
+				Assert(conf->boot_val <= conf->max);
+				if (conf->assign_hook)
+					if (!(*conf->assign_hook) (conf->boot_val, true,
+											   PGC_S_DEFAULT))
+						elog(FATAL, "failed to initialize %s to %g",
+							 conf->gen.name, conf->boot_val);
+				*conf->variable = conf->reset_val = conf->boot_val;
+				break;
+			}
+		case PGC_STRING:
 			{
-				const char *newstr;
+				struct config_string *conf = (struct config_string *) gconf;
+				char	   *str;
 
-				newstr = (*conf->assign_hook) (str, true,
-											   PGC_S_DEFAULT);
-				if (newstr == NULL)
+				*conf->variable = NULL;
+				conf->reset_val = NULL;
+
+				if (conf->boot_val == NULL)
 				{
-					elog(FATAL, "failed to initialize %s to \"%s\"",
-						 conf->gen.name, str);
+					/* leave the value NULL, do not call assign hook */
+					break;
 				}
-				else if (newstr != str)
+
+				str = guc_strdup(FATAL, conf->boot_val);
+				conf->reset_val = str;
+
+				if (conf->assign_hook)
 				{
-					free(str);
+					const char *newstr;
 
-					/*
-					 * See notes in set_config_option about casting
-					 */
-					str = (char *) newstr;
-					conf->reset_val = str;
+					newstr = (*conf->assign_hook) (str, true,
+												   PGC_S_DEFAULT);
+					if (newstr == NULL)
+					{
+						elog(FATAL, "failed to initialize %s to \"%s\"",
+							 conf->gen.name, str);
+					}
+					else if (newstr != str)
+					{
+						free(str);
+
+						/*
+						 * See notes in set_config_option about casting
+						 */
+						str = (char *) newstr;
+						conf->reset_val = str;
+					}
 				}
+				*conf->variable = str;
+				break;
 			}
-			*conf->variable = str;
-			break;
-		}
 		case PGC_ENUM:
-		{
-			struct config_enum *conf = (struct config_enum *) gconf;
-
-			if (conf->assign_hook)
-				if (!(*conf->assign_hook) (conf->boot_val, true,
-										   PGC_S_DEFAULT))
-					elog(FATAL, "failed to initialize %s to %s",
-						 conf->gen.name, 
-						 config_enum_lookup_by_value(conf, conf->boot_val));
-			*conf->variable = conf->reset_val = conf->boot_val;
-			break;
-		}
+			{
+				struct config_enum *conf = (struct config_enum *) gconf;
+
+				if (conf->assign_hook)
+					if (!(*conf->assign_hook) (conf->boot_val, true,
+											   PGC_S_DEFAULT))
+						elog(FATAL, "failed to initialize %s to %s",
+							 conf->gen.name,
+						  config_enum_lookup_by_value(conf, conf->boot_val));
+				*conf->variable = conf->reset_val = conf->boot_val;
+				break;
+			}
 	}
 }
 
@@ -3552,7 +3679,8 @@ ResetAllOptions(void)
 					if (conf->assign_hook)
 						if (!(*conf->assign_hook) (conf->reset_val, true,
 												   PGC_S_SESSION))
-							elog(ERROR, "failed to reset %s", conf->gen.name);
+							elog(ERROR, "failed to reset %s to %d",
+								 conf->gen.name, (int) conf->reset_val);
 					*conf->variable = conf->reset_val;
 					break;
 				}
@@ -3563,7 +3691,8 @@ ResetAllOptions(void)
 					if (conf->assign_hook)
 						if (!(*conf->assign_hook) (conf->reset_val, true,
 												   PGC_S_SESSION))
-							elog(ERROR, "failed to reset %s", conf->gen.name);
+							elog(ERROR, "failed to reset %s to %d",
+								 conf->gen.name, conf->reset_val);
 					*conf->variable = conf->reset_val;
 					break;
 				}
@@ -3574,7 +3703,8 @@ ResetAllOptions(void)
 					if (conf->assign_hook)
 						if (!(*conf->assign_hook) (conf->reset_val, true,
 												   PGC_S_SESSION))
-							elog(ERROR, "failed to reset %s", conf->gen.name);
+							elog(ERROR, "failed to reset %s to %g",
+								 conf->gen.name, conf->reset_val);
 					*conf->variable = conf->reset_val;
 					break;
 				}
@@ -3593,7 +3723,8 @@ ResetAllOptions(void)
 						newstr = (*conf->assign_hook) (str, true,
 													   PGC_S_SESSION);
 						if (newstr == NULL)
-							elog(ERROR, "failed to reset %s", conf->gen.name);
+							elog(ERROR, "failed to reset %s to \"%s\"",
+								 conf->gen.name, str);
 						else if (newstr != str)
 						{
 							/*
@@ -3613,7 +3744,9 @@ ResetAllOptions(void)
 					if (conf->assign_hook)
 						if (!(*conf->assign_hook) (conf->reset_val, true,
 												   PGC_S_SESSION))
-							elog(ERROR, "failed to reset %s", conf->gen.name);
+							elog(ERROR, "failed to reset %s to %s",
+								 conf->gen.name,
+								 config_enum_lookup_by_value(conf, conf->reset_val));
 					*conf->variable = conf->reset_val;
 					break;
 				}
@@ -3884,8 +4017,8 @@ AtEOXact_GUC(bool isCommit, int nestLevel)
 								if (conf->assign_hook)
 									if (!(*conf->assign_hook) (newval,
 													   true, PGC_S_OVERRIDE))
-										elog(LOG, "failed to commit %s",
-											 conf->gen.name);
+										elog(LOG, "failed to commit %s as %d",
+											 conf->gen.name, (int) newval);
 								*conf->variable = newval;
 								changed = true;
 							}
@@ -3901,8 +4034,8 @@ AtEOXact_GUC(bool isCommit, int nestLevel)
 								if (conf->assign_hook)
 									if (!(*conf->assign_hook) (newval,
 													   true, PGC_S_OVERRIDE))
-										elog(LOG, "failed to commit %s",
-											 conf->gen.name);
+										elog(LOG, "failed to commit %s as %d",
+											 conf->gen.name, newval);
 								*conf->variable = newval;
 								changed = true;
 							}
@@ -3918,8 +4051,8 @@ AtEOXact_GUC(bool isCommit, int nestLevel)
 								if (conf->assign_hook)
 									if (!(*conf->assign_hook) (newval,
 													   true, PGC_S_OVERRIDE))
-										elog(LOG, "failed to commit %s",
-											 conf->gen.name);
+										elog(LOG, "failed to commit %s as %g",
+											 conf->gen.name, newval);
 								*conf->variable = newval;
 								changed = true;
 							}
@@ -3939,8 +4072,8 @@ AtEOXact_GUC(bool isCommit, int nestLevel)
 									newstr = (*conf->assign_hook) (newval, true,
 															 PGC_S_OVERRIDE);
 									if (newstr == NULL)
-										elog(LOG, "failed to commit %s",
-											 conf->gen.name);
+										elog(LOG, "failed to commit %s as \"%s\"",
+											 conf->gen.name, newval);
 									else if (newstr != newval)
 									{
 										/*
@@ -3971,15 +4104,16 @@ AtEOXact_GUC(bool isCommit, int nestLevel)
 					case PGC_ENUM:
 						{
 							struct config_enum *conf = (struct config_enum *) gconf;
-							int newval = newvalue.enumval;
+							int			newval = newvalue.enumval;
 
 							if (*conf->variable != newval)
 							{
 								if (conf->assign_hook)
 									if (!(*conf->assign_hook) (newval,
-															   true, PGC_S_OVERRIDE))
-										elog(LOG, "failed to commit %s",
-											 conf->gen.name);
+													   true, PGC_S_OVERRIDE))
+										elog(LOG, "failed to commit %s as %s",
+											 conf->gen.name,
+											 config_enum_lookup_by_value(conf, newval));
 								*conf->variable = newval;
 								changed = true;
 							}
@@ -4060,74 +4194,6 @@ ReportGUCOption(struct config_generic * record)
 	}
 }
 
-
-/*
- * Try to interpret value as boolean value.  Valid values are: true,
- * false, yes, no, on, off, 1, 0; as well as unique prefixes thereof.
- * If the string parses okay, return true, else false.
- * If okay and result is not NULL, return the value in *result.
- */
-bool
-parse_bool(const char *value, bool *result)
-{
-	size_t		len = strlen(value);
-
-	if (pg_strncasecmp(value, "true", len) == 0)
-	{
-		if (result)
-			*result = true;
-	}
-	else if (pg_strncasecmp(value, "false", len) == 0)
-	{
-		if (result)
-			*result = false;
-	}
-
-	else if (pg_strncasecmp(value, "yes", len) == 0)
-	{
-		if (result)
-			*result = true;
-	}
-	else if (pg_strncasecmp(value, "no", len) == 0)
-	{
-		if (result)
-			*result = false;
-	}
-
-	/* 'o' is not unique enough */
-	else if (pg_strncasecmp(value, "on", (len > 2 ? len : 2)) == 0)
-	{
-		if (result)
-			*result = true;
-	}
-	else if (pg_strncasecmp(value, "off", (len > 2 ? len : 2)) == 0)
-	{
-		if (result)
-			*result = false;
-	}
-
-	else if (pg_strcasecmp(value, "1") == 0)
-	{
-		if (result)
-			*result = true;
-	}
-	else if (pg_strcasecmp(value, "0") == 0)
-	{
-		if (result)
-			*result = false;
-	}
-
-	else
-	{
-		if (result)
-			*result = false;	/* suppress compiler warning */
-		return false;
-	}
-	return true;
-}
-
-
-
 /*
  * Try to parse value as an integer.  The accepted formats are the
  * usual decimal, octal, or hexadecimal formats, optionally followed by
@@ -4174,10 +4240,6 @@ parse_int(const char *value, int *result, int flags, const char **hintmsg)
 		/*
 		 * Note: the multiple-switch coding technique here is a bit tedious,
 		 * but seems necessary to avoid intermediate-value overflows.
-		 *
-		 * If INT64_IS_BUSTED (ie, it's really int32) we will fail to detect
-		 * overflow due to units conversion, but there are few enough such
-		 * machines that it does not seem worth trying to be smarter.
 		 */
 		if (flags & GUC_UNIT_MEMORY)
 		{
@@ -4380,7 +4442,7 @@ parse_real(const char *value, double *result)
  * allocated for modification.
  */
 const char *
-config_enum_lookup_by_value(struct config_enum *record, int val)
+config_enum_lookup_by_value(struct config_enum * record, int val)
 {
 	const struct config_enum_entry *entry;
 
@@ -4392,7 +4454,7 @@ config_enum_lookup_by_value(struct config_enum *record, int val)
 
 	elog(ERROR, "could not find enum option %d for %s",
 		 val, record->gen.name);
-	return NULL;		/* silence compiler */
+	return NULL;				/* silence compiler */
 }
 
 
@@ -4403,7 +4465,7 @@ config_enum_lookup_by_value(struct config_enum *record, int val)
  * true. If it's not found, return FALSE and retval is set to 0.
  */
 bool
-config_enum_lookup_by_name(struct config_enum *record, const char *value,
+config_enum_lookup_by_name(struct config_enum * record, const char *value,
 						   int *retval)
 {
 	const struct config_enum_entry *entry;
@@ -4429,16 +4491,16 @@ config_enum_lookup_by_name(struct config_enum *record, const char *value,
  * If suffix is non-NULL, it is added to the end of the string.
  */
 static char *
-config_enum_get_options(struct config_enum *record, const char *prefix,
+config_enum_get_options(struct config_enum * record, const char *prefix,
 						const char *suffix, const char *separator)
 {
 	const struct config_enum_entry *entry;
-	StringInfoData	retstr;
+	StringInfoData retstr;
 	int			seplen;
 
 	initStringInfo(&retstr);
 	appendStringInfoString(&retstr, prefix);
-	
+
 	seplen = strlen(separator);
 	for (entry = record->options; entry && entry->name; entry++)
 	{
@@ -4450,11 +4512,11 @@ config_enum_get_options(struct config_enum *record, const char *prefix,
 	}
 
 	/*
-	 * All the entries may have been hidden, leaving the string empty
-	 * if no prefix was given. This indicates a broken GUC setup, since
-	 * there is no use for an enum without any values, so we just check
-	 * to make sure we don't write to invalid memory instead of actually
-	 * trying to do something smart with it.
+	 * All the entries may have been hidden, leaving the string empty if no
+	 * prefix was given. This indicates a broken GUC setup, since there is no
+	 * use for an enum without any values, so we just check to make sure we
+	 * don't write to invalid memory instead of actually trying to do
+	 * something smart with it.
 	 */
 	if (retstr.len >= seplen)
 	{
@@ -4540,8 +4602,9 @@ set_config_option(const char *name, const char *value,
 		 */
 		elevel = IsUnderPostmaster ? DEBUG3 : LOG;
 	}
-	else if (source == PGC_S_DATABASE || source == PGC_S_USER)
-		elevel = INFO;
+	else if (source == PGC_S_DATABASE || source == PGC_S_USER ||
+			 source == PGC_S_DATABASE_USER)
+		elevel = WARNING;
 	else
 		elevel = ERROR;
 
@@ -4594,18 +4657,16 @@ set_config_option(const char *name, const char *value,
 				if (changeVal && !is_newvalue_equal(record, value))
 					ereport(elevel,
 							(errcode(ERRCODE_CANT_CHANGE_RUNTIME_PARAM),
-							 errmsg("attempted change of parameter \"%s\" ignored",
-									name),
-							 errdetail("This parameter cannot be changed after server start.")));
+					   errmsg("parameter \"%s\" cannot be changed without restarting the server",
+							  name)));
 				return true;
 			}
 			if (context != PGC_POSTMASTER)
 			{
 				ereport(elevel,
 						(errcode(ERRCODE_CANT_CHANGE_RUNTIME_PARAM),
-						 errmsg("attempted change of parameter \"%s\" ignored",
-								name),
-						 errdetail("This parameter cannot be changed after server start.")));
+					   errmsg("parameter \"%s\" cannot be changed without restarting the server",
+							  name)));
 				return false;
 			}
 			break;
@@ -4640,7 +4701,8 @@ set_config_option(const char *name, const char *value,
 				if (IsUnderPostmaster)
 					return true;
 			}
-			else if (context != PGC_BACKEND && context != PGC_POSTMASTER)
+			else if (context != PGC_POSTMASTER && context != PGC_BACKEND &&
+					 source != PGC_S_CLIENT)
 			{
 				ereport(elevel,
 						(errcode(ERRCODE_CANT_CHANGE_RUNTIME_PARAM),
@@ -4664,6 +4726,48 @@ set_config_option(const char *name, const char *value,
 			break;
 	}
 
+	/*
+	 * Disallow changing GUC_NOT_WHILE_SEC_REST values if we are inside a
+	 * security restriction context.  We can reject this regardless of
+	 * the GUC context or source, mainly because sources that it might be
+	 * reasonable to override for won't be seen while inside a function.
+	 *
+	 * Note: variables marked GUC_NOT_WHILE_SEC_REST should usually be marked
+	 * GUC_NO_RESET_ALL as well, because ResetAllOptions() doesn't check this.
+	 * An exception might be made if the reset value is assumed to be "safe".
+	 *
+	 * Note: this flag is currently used for "session_authorization" and
+	 * "role".  We need to prohibit changing these inside a local userid
+	 * context because when we exit it, GUC won't be notified, leaving things
+	 * out of sync.  (This could be fixed by forcing a new GUC nesting level,
+	 * but that would change behavior in possibly-undesirable ways.)  Also,
+	 * we prohibit changing these in a security-restricted operation because
+	 * otherwise RESET could be used to regain the session user's privileges.
+	 */
+	if (record->flags & GUC_NOT_WHILE_SEC_REST)
+	{
+		if (InLocalUserIdChange())
+		{
+			/*
+			 * Phrasing of this error message is historical, but it's the
+			 * most common case.
+			 */
+			ereport(elevel,
+					(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
+					 errmsg("cannot set parameter \"%s\" within security-definer function",
+							name)));
+			return false;
+		}
+		if (InSecurityRestrictedOperation())
+		{
+			ereport(elevel,
+					(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
+					 errmsg("cannot set parameter \"%s\" within security-restricted operation",
+							name)));
+			return false;
+		}
+	}
+
 	/*
 	 * Should we set reset/stacked values?	(If so, the behavior is not
 	 * transactional.)	This is done either when we get a default value from
@@ -4775,7 +4879,7 @@ set_config_option(const char *name, const char *value,
 								(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 						 errmsg("invalid value for parameter \"%s\": \"%s\"",
 								name, value),
-								 hintmsg ? errhint("%s", hintmsg) : 0));
+								 hintmsg ? errhint("%s", _(hintmsg)) : 0));
 						return false;
 					}
 					if (newval < conf->min || newval > conf->max)
@@ -5033,17 +5137,17 @@ set_config_option(const char *name, const char *value,
 				{
 					if (!config_enum_lookup_by_name(conf, value, &newval))
 					{
-						char *hintmsg;
-					   
-						hintmsg	= config_enum_get_options(conf,
-														  "Available values: ",
+						char	   *hintmsg;
+
+						hintmsg = config_enum_get_options(conf,
+														"Available values: ",
 														  ".", ", ");
 
 						ereport(elevel,
 								(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
-								 errmsg("invalid value for parameter \"%s\": \"%s\"",
-										name, value),
-								 hintmsg ? errhint("%s", hintmsg) : 0));
+						 errmsg("invalid value for parameter \"%s\": \"%s\"",
+								name, value),
+								 hintmsg ? errhint("%s", _(hintmsg)) : 0));
 
 						if (hintmsg)
 							pfree(hintmsg);
@@ -5067,9 +5171,9 @@ set_config_option(const char *name, const char *value,
 					{
 						ereport(elevel,
 								(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
-								 errmsg("invalid value for parameter \"%s\": \"%s\"",
-										name, 
-										config_enum_lookup_by_value(conf, newval))));
+						 errmsg("invalid value for parameter \"%s\": \"%s\"",
+								name,
+								config_enum_lookup_by_value(conf, newval))));
 						return false;
 					}
 
@@ -5117,8 +5221,8 @@ set_config_sourcefile(const char *name, char *sourcefile, int sourceline)
 	int			elevel;
 
 	/*
-	 * To avoid cluttering the log, only the postmaster bleats loudly
-	 * about problems with the config file.
+	 * To avoid cluttering the log, only the postmaster bleats loudly about
+	 * problems with the config file.
 	 */
 	elevel = IsUnderPostmaster ? DEBUG3 : LOG;
 
@@ -5156,11 +5260,15 @@ SetConfigOption(const char *name, const char *value,
  * Fetch the current value of the option `name'. If the option doesn't exist,
  * throw an ereport and don't return.
  *
+ * If restrict_superuser is true, we also enforce that only superusers can
+ * see GUC_SUPERUSER_ONLY variables.  This should only be passed as true
+ * in user-driven calls.
+ *
  * The string is *not* allocated for modification and is really only
  * valid until the next call to configuration related functions.
  */
 const char *
-GetConfigOption(const char *name)
+GetConfigOption(const char *name, bool restrict_superuser)
 {
 	struct config_generic *record;
 	static char buffer[256];
@@ -5170,7 +5278,9 @@ GetConfigOption(const char *name)
 		ereport(ERROR,
 				(errcode(ERRCODE_UNDEFINED_OBJECT),
 			   errmsg("unrecognized configuration parameter \"%s\"", name)));
-	if ((record->flags & GUC_SUPERUSER_ONLY) && !superuser())
+	if (restrict_superuser &&
+		(record->flags & GUC_SUPERUSER_ONLY) &&
+		!superuser())
 		ereport(ERROR,
 				(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
 				 errmsg("must be superuser to examine \"%s\"", name)));
@@ -5195,7 +5305,7 @@ GetConfigOption(const char *name)
 
 		case PGC_ENUM:
 			return config_enum_lookup_by_value((struct config_enum *) record,
-											*((struct config_enum *) record)->variable);
+								 *((struct config_enum *) record)->variable);
 	}
 	return NULL;
 }
@@ -5243,27 +5353,11 @@ GetConfigOptionResetString(const char *name)
 
 		case PGC_ENUM:
 			return config_enum_lookup_by_value((struct config_enum *) record,
-										    ((struct config_enum *) record)->reset_val);
+								 ((struct config_enum *) record)->reset_val);
 	}
 	return NULL;
 }
 
-/*
- * Detect whether the given configuration option can only be set by
- * a superuser.
- */
-bool
-IsSuperuserConfigOption(const char *name)
-{
-	struct config_generic *record;
-
-	record = find_option(name, false, ERROR);
-	/* On an unrecognized name, don't error, just return false. */
-	if (record == NULL)
-		return false;
-	return (record->context == PGC_SUSET);
-}
-
 
 /*
  * GUC_complaint_elevel
@@ -5273,7 +5367,7 @@ IsSuperuserConfigOption(const char *name)
  * report (in addition to the generic "invalid value for option FOO" that
  * guc.c will provide).  Note that the result might be ERROR or a lower
  * level, so the caller must be prepared for control to return from ereport,
- * or not.  If control does return, return false/NULL from the hook function.
+ * or not.	If control does return, return false/NULL from the hook function.
  *
  * At some point it'd be nice to replace this with a mechanism that allows
  * the custom message to become the DETAIL line of guc.c's generic message.
@@ -5295,9 +5389,9 @@ GUC_complaint_elevel(GucSource source)
 	{
 		/*
 		 * If we're a postmaster child, this is probably "undo" during
-		 * transaction abort, so we don't want to clutter the log.  There's
-		 * a small chance of a real problem with an OVERRIDE setting,
-		 * though, so suppressing the message entirely wouldn't be desirable.
+		 * transaction abort, so we don't want to clutter the log.  There's a
+		 * small chance of a real problem with an OVERRIDE setting, though, so
+		 * suppressing the message entirely wouldn't be desirable.
 		 */
 		elevel = IsUnderPostmaster ? DEBUG5 : LOG;
 	}
@@ -5353,25 +5447,25 @@ flatten_set_variable_args(const char *name, List *args)
 
 	/*
 	 * Each list member may be a plain A_Const node, or an A_Const within a
-	 * TypeCast; the latter case is supported only for ConstInterval
-	 * arguments (for SET TIME ZONE).
+	 * TypeCast; the latter case is supported only for ConstInterval arguments
+	 * (for SET TIME ZONE).
 	 */
 	foreach(l, args)
 	{
-		Node       *arg = (Node *) lfirst(l);
+		Node	   *arg = (Node *) lfirst(l);
 		char	   *val;
-		TypeName   *typename = NULL;
-		A_Const	   *con;
+		TypeName   *typeName = NULL;
+		A_Const    *con;
 
 		if (l != list_head(args))
 			appendStringInfo(&buf, ", ");
 
 		if (IsA(arg, TypeCast))
 		{
-			TypeCast *tc = (TypeCast *) arg;
+			TypeCast   *tc = (TypeCast *) arg;
 
 			arg = tc->arg;
-			typename = tc->typename;
+			typeName = tc->typeName;
 		}
 
 		if (!IsA(arg, A_Const))
@@ -5389,7 +5483,7 @@ flatten_set_variable_args(const char *name, List *args)
 				break;
 			case T_String:
 				val = strVal(&con->val);
-				if (typename != NULL)
+				if (typeName != NULL)
 				{
 					/*
 					 * Must be a ConstInterval argument for TIME ZONE. Coerce
@@ -5401,7 +5495,7 @@ flatten_set_variable_args(const char *name, List *args)
 					Datum		interval;
 					char	   *intervalout;
 
-					typoid = typenameTypeId(NULL, typename, &typmod);
+					typoid = typenameTypeId(NULL, typeName, &typmod);
 					Assert(typoid == INTERVALOID);
 
 					interval =
@@ -5625,6 +5719,17 @@ init_custom_variable(const char *name,
 {
 	struct config_generic *gen;
 
+	/*
+	 * Only allow custom PGC_POSTMASTER variables to be created during shared
+	 * library preload; any later than that, we can't ensure that the value
+	 * doesn't change after startup.  This is a fatal elog if it happens; just
+	 * erroring out isn't safe because we don't know what the calling loadable
+	 * module might already have hooked into.
+	 */
+	if (context == PGC_POSTMASTER &&
+		!process_shared_preload_libraries_in_progress)
+		elog(FATAL, "cannot create PGC_POSTMASTER variables after startup");
+
 	gen = (struct config_generic *) guc_malloc(ERROR, sz);
 	memset(gen, 0, sz);
 
@@ -5650,7 +5755,7 @@ define_custom_variable(struct config_generic * variable)
 	const char **nameAddr = &name;
 	const char *value;
 	struct config_string *pHolder;
-	GucContext phcontext;
+	GucContext	phcontext;
 	struct config_generic **res;
 
 	/*
@@ -5697,9 +5802,9 @@ define_custom_variable(struct config_generic * variable)
 	*res = variable;
 
 	/*
-	 * Infer context for assignment based on source of existing value.
-	 * We can't tell this with exact accuracy, but we can at least do
-	 * something reasonable in typical cases.
+	 * Infer context for assignment based on source of existing value. We
+	 * can't tell this with exact accuracy, but we can at least do something
+	 * reasonable in typical cases.
 	 */
 	switch (pHolder->gen.source)
 	{
@@ -5707,10 +5812,20 @@ define_custom_variable(struct config_generic * variable)
 		case PGC_S_ENV_VAR:
 		case PGC_S_FILE:
 		case PGC_S_ARGV:
-			phcontext = PGC_SIGHUP;
+
+			/*
+			 * If we got past the check in init_custom_variable, we can safely
+			 * assume that any existing value for a PGC_POSTMASTER variable
+			 * was set in postmaster context.
+			 */
+			if (variable->context == PGC_POSTMASTER)
+				phcontext = PGC_POSTMASTER;
+			else
+				phcontext = PGC_SIGHUP;
 			break;
 		case PGC_S_DATABASE:
 		case PGC_S_USER:
+		case PGC_S_DATABASE_USER:
 		case PGC_S_CLIENT:
 		case PGC_S_SESSION:
 		default:
@@ -5728,9 +5843,17 @@ define_custom_variable(struct config_generic * variable)
 	value = *pHolder->variable;
 
 	if (value)
-		set_config_option(name, value,
-						  phcontext, pHolder->gen.source,
-						  GUC_ACTION_SET, true);
+	{
+		if (set_config_option(name, value,
+							  phcontext, pHolder->gen.source,
+							  GUC_ACTION_SET, true))
+		{
+			/* Also copy over any saved source-location information */
+			if (pHolder->gen.sourcefile)
+				set_config_sourcefile(name, pHolder->gen.sourcefile,
+									  pHolder->gen.sourceline);
+		}
+	}
 
 	/*
 	 * Free up as much as we conveniently can of the placeholder structure
@@ -5854,7 +5977,7 @@ DefineCustomEnumVariable(const char *name,
 						 const char *long_desc,
 						 int *valueAddr,
 						 int bootValue,
-						 const struct config_enum_entry *options,
+						 const struct config_enum_entry * options,
 						 GucContext context,
 						 int flags,
 						 GucEnumAssignHook assign_hook,
@@ -5877,22 +6000,21 @@ DefineCustomEnumVariable(const char *name,
 void
 EmitWarningsOnPlaceholders(const char *className)
 {
-	struct config_generic **vars = guc_variables;
-	struct config_generic **last = vars + num_guc_variables;
-
-	int			nameLen = strlen(className);
+	int			classLen = strlen(className);
+	int			i;
 
-	while (vars < last)
+	for (i = 0; i < num_guc_variables; i++)
 	{
-		struct config_generic *var = *vars++;
+		struct config_generic *var = guc_variables[i];
 
 		if ((var->flags & GUC_CUSTOM_PLACEHOLDER) != 0 &&
-			strncmp(className, var->name, nameLen) == 0 &&
-			var->name[nameLen] == GUC_QUALIFIER_SEPARATOR)
+			strncmp(className, var->name, classLen) == 0 &&
+			var->name[classLen] == GUC_QUALIFIER_SEPARATOR)
 		{
-			ereport(INFO,
+			ereport(WARNING,
 					(errcode(ERRCODE_UNDEFINED_OBJECT),
-					 errmsg("unrecognized configuration parameter \"%s\"", var->name)));
+					 errmsg("unrecognized configuration parameter \"%s\"",
+							var->name)));
 		}
 	}
 }
@@ -5925,7 +6047,6 @@ GetPGVariableResultDesc(const char *name)
 						   TEXTOID, -1, 0);
 		TupleDescInitEntry(tupdesc, (AttrNumber) 3, "description",
 						   TEXTOID, -1, 0);
-
 	}
 	else
 	{
@@ -5981,7 +6102,8 @@ ShowAllGUCConfig(DestReceiver *dest)
 	int			i;
 	TupOutputState *tstate;
 	TupleDesc	tupdesc;
-	char	   *values[3];
+	Datum	    values[3];
+	bool		isnull[3] = { false, false, false };
 
 	/* need a tuple descriptor representing three TEXT columns */
 	tupdesc = CreateTemplateTupleDesc(3, false);
@@ -5992,29 +6114,46 @@ ShowAllGUCConfig(DestReceiver *dest)
 	TupleDescInitEntry(tupdesc, (AttrNumber) 3, "description",
 					   TEXTOID, -1, 0);
 
-
 	/* prepare for projection of tuples */
 	tstate = begin_tup_output_tupdesc(dest, tupdesc);
 
 	for (i = 0; i < num_guc_variables; i++)
 	{
 		struct config_generic *conf = guc_variables[i];
+		char   *setting;
 
 		if ((conf->flags & GUC_NO_SHOW_ALL) ||
 			((conf->flags & GUC_SUPERUSER_ONLY) && !am_superuser))
 			continue;
 
 		/* assign to the values array */
-		values[0] = (char *) conf->name;
-		values[1] = _ShowOption(conf, true);
-		values[2] = (char *) conf->short_desc;
+		values[0] = PointerGetDatum(cstring_to_text(conf->name));
+
+		setting = _ShowOption(conf, true);
+		if (setting)
+		{
+			values[1] = PointerGetDatum(cstring_to_text(setting));
+			isnull[1] = false;
+		}
+		else
+		{
+			values[1] = PointerGetDatum(NULL);
+			isnull[1] = true;
+		}
+
+		values[2] = PointerGetDatum(cstring_to_text(conf->short_desc));
 
 		/* send it to dest */
-		do_tup_output(tstate, values);
+		do_tup_output(tstate, values, isnull);
 
 		/* clean up */
-		if (values[1] != NULL)
-			pfree(values[1]);
+		pfree(DatumGetPointer(values[0]));
+		if (setting)
+		{
+			pfree(setting);
+			pfree(DatumGetPointer(values[1]));
+		}
+		pfree(DatumGetPointer(values[2]));
 	}
 
 	end_tup_output(tstate);
@@ -6169,13 +6308,13 @@ GetConfigOptionByNum(int varnum, const char **values, bool *noshow)
 				/* enumvals */
 				values[11] = NULL;
 
- 				/* boot_val */
- 				snprintf(buffer, sizeof(buffer), "%d", lconf->boot_val);
- 				values[12] = pstrdup(buffer);
+				/* boot_val */
+				snprintf(buffer, sizeof(buffer), "%d", lconf->boot_val);
+				values[12] = pstrdup(buffer);
 
- 				/* reset_val */
- 				snprintf(buffer, sizeof(buffer), "%d", lconf->reset_val);
- 				values[13] = pstrdup(buffer);
+				/* reset_val */
+				snprintf(buffer, sizeof(buffer), "%d", lconf->reset_val);
+				values[13] = pstrdup(buffer);
 			}
 			break;
 
@@ -6194,19 +6333,19 @@ GetConfigOptionByNum(int varnum, const char **values, bool *noshow)
 				/* enumvals */
 				values[11] = NULL;
 
- 				/* boot_val */
- 				snprintf(buffer, sizeof(buffer), "%g", lconf->boot_val);
- 				values[12] = pstrdup(buffer);
+				/* boot_val */
+				snprintf(buffer, sizeof(buffer), "%g", lconf->boot_val);
+				values[12] = pstrdup(buffer);
 
- 				/* reset_val */
- 				snprintf(buffer, sizeof(buffer), "%g", lconf->reset_val);
- 				values[13] = pstrdup(buffer);
+				/* reset_val */
+				snprintf(buffer, sizeof(buffer), "%g", lconf->reset_val);
+				values[13] = pstrdup(buffer);
 			}
 			break;
 
 		case PGC_STRING:
 			{
- 				struct config_string *lconf = (struct config_string *) conf;
+				struct config_string *lconf = (struct config_string *) conf;
 
 				/* min_val */
 				values[9] = NULL;
@@ -6217,15 +6356,15 @@ GetConfigOptionByNum(int varnum, const char **values, bool *noshow)
 				/* enumvals */
 				values[11] = NULL;
 
- 				/* boot_val */
- 				if (lconf->boot_val == NULL)
- 					values[12] = NULL;
+				/* boot_val */
+				if (lconf->boot_val == NULL)
+					values[12] = NULL;
 				else
 					values[12] = pstrdup(lconf->boot_val);
 
- 				/* reset_val */
- 				if (lconf->reset_val == NULL)
- 					values[13] = NULL;
+				/* reset_val */
+				if (lconf->reset_val == NULL)
+					values[13] = NULL;
 				else
 					values[13] = pstrdup(lconf->reset_val);
 			}
@@ -6233,7 +6372,7 @@ GetConfigOptionByNum(int varnum, const char **values, bool *noshow)
 
 		case PGC_ENUM:
 			{
- 				struct config_enum *lconf = (struct config_enum *) conf;
+				struct config_enum *lconf = (struct config_enum *) conf;
 
 				/* min_val */
 				values[9] = NULL;
@@ -6242,17 +6381,21 @@ GetConfigOptionByNum(int varnum, const char **values, bool *noshow)
 				values[10] = NULL;
 
 				/* enumvals */
-				/* NOTE! enumvals with double quotes in them are not supported! */
+
+				/*
+				 * NOTE! enumvals with double quotes in them are not
+				 * supported!
+				 */
 				values[11] = config_enum_get_options((struct config_enum *) conf,
 													 "{\"", "\"}", "\",\"");
 
- 				/* boot_val */
+				/* boot_val */
 				values[12] = pstrdup(config_enum_lookup_by_value(lconf,
-																 lconf->boot_val));
+														   lconf->boot_val));
 
- 				/* reset_val */
+				/* reset_val */
 				values[13] = pstrdup(config_enum_lookup_by_value(lconf,
-																 lconf->reset_val));
+														  lconf->reset_val));
 			}
 			break;
 
@@ -6271,18 +6414,18 @@ GetConfigOptionByNum(int varnum, const char **values, bool *noshow)
 				/* enumvals */
 				values[11] = NULL;
 
- 				/* boot_val */
- 				values[12] = NULL;
+				/* boot_val */
+				values[12] = NULL;
 
- 				/* reset_val */
- 				values[13] = NULL;
+				/* reset_val */
+				values[13] = NULL;
 			}
 			break;
 	}
 
-	/* 
-	 * If the setting came from a config file, set the source location.
-	 * For security reasons, we don't show source file/line number for
+	/*
+	 * If the setting came from a config file, set the source location. For
+	 * security reasons, we don't show source file/line number for
 	 * non-superusers.
 	 */
 	if (conf->source == PGC_S_FILE && superuser())
@@ -6383,10 +6526,10 @@ show_all_settings(PG_FUNCTION_ARGS)
 						   TEXTOID, -1, 0);
 		TupleDescInitEntry(tupdesc, (AttrNumber) 12, "enumvals",
 						   TEXTARRAYOID, -1, 0);
- 		TupleDescInitEntry(tupdesc, (AttrNumber) 13, "boot_val",
- 						   TEXTOID, -1, 0);
- 		TupleDescInitEntry(tupdesc, (AttrNumber) 14, "reset_val",
- 						   TEXTOID, -1, 0);
+		TupleDescInitEntry(tupdesc, (AttrNumber) 13, "boot_val",
+						   TEXTOID, -1, 0);
+		TupleDescInitEntry(tupdesc, (AttrNumber) 14, "reset_val",
+						   TEXTOID, -1, 0);
 		TupleDescInitEntry(tupdesc, (AttrNumber) 15, "sourcefile",
 						   TEXTOID, -1, 0);
 		TupleDescInitEntry(tupdesc, (AttrNumber) 16, "sourceline",
@@ -6480,10 +6623,7 @@ _ShowOption(struct config_generic * record, bool use_units)
 				{
 					/*
 					 * Use int64 arithmetic to avoid overflows in units
-					 * conversion.  If INT64_IS_BUSTED we might overflow
-					 * anyway and print bogus answers, but there are few
-					 * enough such machines that it doesn't seem worth
-					 * trying harder.
+					 * conversion.
 					 */
 					int64		result = *conf->variable;
 					const char *unit;
@@ -6596,7 +6736,7 @@ _ShowOption(struct config_generic * record, bool use_units)
 			{
 				struct config_enum *conf = (struct config_enum *) record;
 
-				if(conf->show_hook)
+				if (conf->show_hook)
 					val = (*conf->show_hook) ();
 				else
 					val = config_enum_lookup_by_value(conf, *conf->variable);
@@ -6677,19 +6817,82 @@ is_newvalue_equal(struct config_generic * record, const char *newvalue)
 #ifdef EXEC_BACKEND
 
 /*
- *	This routine dumps out all non-default GUC options into a binary
+ *	These routines dump out all non-default GUC options into a binary
  *	file that is read by all exec'ed backends.  The format is:
  *
  *		variable name, string, null terminated
  *		variable value, string, null terminated
  *		variable source, integer
  */
+static void
+write_one_nondefault_variable(FILE *fp, struct config_generic * gconf)
+{
+	if (gconf->source == PGC_S_DEFAULT)
+		return;
+
+	fprintf(fp, "%s", gconf->name);
+	fputc(0, fp);
+
+	switch (gconf->vartype)
+	{
+		case PGC_BOOL:
+			{
+				struct config_bool *conf = (struct config_bool *) gconf;
+
+				if (*conf->variable)
+					fprintf(fp, "true");
+				else
+					fprintf(fp, "false");
+			}
+			break;
+
+		case PGC_INT:
+			{
+				struct config_int *conf = (struct config_int *) gconf;
+
+				fprintf(fp, "%d", *conf->variable);
+			}
+			break;
+
+		case PGC_REAL:
+			{
+				struct config_real *conf = (struct config_real *) gconf;
+
+				/* Could lose precision here? */
+				fprintf(fp, "%f", *conf->variable);
+			}
+			break;
+
+		case PGC_STRING:
+			{
+				struct config_string *conf = (struct config_string *) gconf;
+
+				fprintf(fp, "%s", *conf->variable);
+			}
+			break;
+
+		case PGC_ENUM:
+			{
+				struct config_enum *conf = (struct config_enum *) gconf;
+
+				fprintf(fp, "%s",
+						config_enum_lookup_by_value(conf, *conf->variable));
+			}
+			break;
+	}
+
+	fputc(0, fp);
+
+	fwrite(&gconf->source, sizeof(gconf->source), 1, fp);
+}
+
 void
 write_nondefault_variables(GucContext context)
 {
-	int			i;
 	int			elevel;
 	FILE	   *fp;
+	struct config_generic *cvc_conf;
+	int			i;
 
 	Assert(context == PGC_POSTMASTER || context == PGC_SIGHUP);
 
@@ -6708,66 +6911,20 @@ write_nondefault_variables(GucContext context)
 		return;
 	}
 
+	/*
+	 * custom_variable_classes must be written out first; otherwise we might
+	 * reject custom variable values while reading the file.
+	 */
+	cvc_conf = find_option("custom_variable_classes", false, ERROR);
+	if (cvc_conf)
+		write_one_nondefault_variable(fp, cvc_conf);
+
 	for (i = 0; i < num_guc_variables; i++)
 	{
 		struct config_generic *gconf = guc_variables[i];
 
-		if (gconf->source != PGC_S_DEFAULT)
-		{
-			fprintf(fp, "%s", gconf->name);
-			fputc(0, fp);
-
-			switch (gconf->vartype)
-			{
-				case PGC_BOOL:
-					{
-						struct config_bool *conf = (struct config_bool *) gconf;
-
-						if (*conf->variable == 0)
-							fprintf(fp, "false");
-						else
-							fprintf(fp, "true");
-					}
-					break;
-
-				case PGC_INT:
-					{
-						struct config_int *conf = (struct config_int *) gconf;
-
-						fprintf(fp, "%d", *conf->variable);
-					}
-					break;
-
-				case PGC_REAL:
-					{
-						struct config_real *conf = (struct config_real *) gconf;
-
-						/* Could lose precision here? */
-						fprintf(fp, "%f", *conf->variable);
-					}
-					break;
-
-				case PGC_STRING:
-					{
-						struct config_string *conf = (struct config_string *) gconf;
-
-						fprintf(fp, "%s", *conf->variable);
-					}
-					break;
-
-				case PGC_ENUM:
-					{
-						struct config_enum *conf = (struct config_enum *) gconf;
-						
-						fprintf(fp, "%s", config_enum_lookup_by_value(conf, *conf->variable));
-					}
-					break;
-			}
-
-			fputc(0, fp);
-
-			fwrite(&gconf->source, sizeof(gconf->source), 1, fp);
-		}
+		if (gconf != cvc_conf)
+			write_one_nondefault_variable(fp, gconf);
 	}
 
 	if (FreeFile(fp))
@@ -7144,7 +7301,7 @@ assign_log_destination(const char *value, bool doit, GucSource source)
 		list_free(elemlist);
 		ereport(GUC_complaint_elevel(source),
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
-			errmsg("invalid list syntax for parameter \"log_destination\"")));
+		   errmsg("invalid list syntax for parameter \"log_destination\"")));
 		return NULL;
 	}
 
@@ -7283,11 +7440,11 @@ assign_custom_variable_classes(const char *newval, bool doit, GucSource source)
 			continue;
 		}
 
-		if (hasSpaceAfterToken || !isalnum((unsigned char) c))
+		if (hasSpaceAfterToken || !(isalnum((unsigned char) c) || c == '_'))
 		{
 			/*
-			 * Syntax error due to token following space after token or non
-			 * alpha numeric character
+			 * Syntax error due to token following space after token or
+			 * non-identifier character
 			 */
 			pfree(buf.data);
 			return NULL;
@@ -7322,6 +7479,21 @@ assign_debug_assertions(bool newval, bool doit, GucSource source)
 	return true;
 }
 
+static bool
+assign_bonjour(bool newval, bool doit, GucSource source)
+{
+#ifndef USE_BONJOUR
+	if (newval)
+	{
+		ereport(GUC_complaint_elevel(source),
+				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+				 errmsg("Bonjour is not supported by this build")));
+		return false;
+	}
+#endif
+	return true;
+}
+
 static bool
 assign_ssl(bool newval, bool doit, GucSource source)
 {
@@ -7383,6 +7555,18 @@ assign_transaction_read_only(bool newval, bool doit, GucSource source)
 		if (source != PGC_S_OVERRIDE)
 			return false;
 	}
+
+	/* Can't go to r/w mode while recovery is still active */
+	if (newval == false && XactReadOnly && RecoveryInProgress())
+	{
+		ereport(GUC_complaint_elevel(source),
+				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+				 errmsg("cannot set transaction read-write mode during recovery")));
+		/* source == PGC_S_OVERRIDE means do it anyway, eg at xact abort */
+		if (source != PGC_S_OVERRIDE)
+			return false;
+	}
+
 	return true;
 }
 
@@ -7524,11 +7708,11 @@ show_tcp_keepalives_count(void)
 static bool
 assign_maxconnections(int newval, bool doit, GucSource source)
 {
-	if (newval + autovacuum_max_workers > INT_MAX / 4)
+	if (newval + autovacuum_max_workers + 1 > INT_MAX / 4)
 		return false;
 
 	if (doit)
-		MaxBackends = newval + autovacuum_max_workers;
+		MaxBackends = newval + autovacuum_max_workers + 1;
 
 	return true;
 }
@@ -7536,33 +7720,121 @@ assign_maxconnections(int newval, bool doit, GucSource source)
 static bool
 assign_autovacuum_max_workers(int newval, bool doit, GucSource source)
 {
-	if (newval + MaxConnections > INT_MAX / 4)
+	if (MaxConnections + newval + 1 > INT_MAX / 4)
 		return false;
 
 	if (doit)
-		MaxBackends = newval + MaxConnections;
+		MaxBackends = MaxConnections + newval + 1;
 
 	return true;
 }
 
+static bool
+assign_effective_io_concurrency(int newval, bool doit, GucSource source)
+{
+#ifdef USE_PREFETCH
+	double		new_prefetch_pages = 0.0;
+	int			i;
+
+	/*----------
+	 * The user-visible GUC parameter is the number of drives (spindles),
+	 * which we need to translate to a number-of-pages-to-prefetch target.
+	 *
+	 * The expected number of prefetch pages needed to keep N drives busy is:
+	 *
+	 * drives |   I/O requests
+	 * -------+----------------
+	 *		1 |   1
+	 *		2 |   2/1 + 2/2 = 3
+	 *		3 |   3/1 + 3/2 + 3/3 = 5 1/2
+	 *		4 |   4/1 + 4/2 + 4/3 + 4/4 = 8 1/3
+	 *		n |   n * H(n)
+	 *
+	 * This is called the "coupon collector problem" and H(n) is called the
+	 * harmonic series.  This could be approximated by n * ln(n), but for
+	 * reasonable numbers of drives we might as well just compute the series.
+	 *
+	 * Alternatively we could set the target to the number of pages necessary
+	 * so that the expected number of active spindles is some arbitrary
+	 * percentage of the total.  This sounds the same but is actually slightly
+	 * different.  The result ends up being ln(1-P)/ln((n-1)/n) where P is
+	 * that desired fraction.
+	 *
+	 * Experimental results show that both of these formulas aren't aggressive
+	 * enough, but we don't really have any better proposals.
+	 *
+	 * Note that if newval = 0 (disabled), we must set target = 0.
+	 *----------
+	 */
+
+	for (i = 1; i <= newval; i++)
+		new_prefetch_pages += (double) newval / (double) i;
+
+	/* This range check shouldn't fail, but let's be paranoid */
+	if (new_prefetch_pages >= 0.0 && new_prefetch_pages < (double) INT_MAX)
+	{
+		if (doit)
+			target_prefetch_pages = (int) rint(new_prefetch_pages);
+		return true;
+	}
+	else
+		return false;
+#else
+	return true;
+#endif   /* USE_PREFETCH */
+}
+
 static const char *
 assign_pgstat_temp_directory(const char *newval, bool doit, GucSource source)
 {
 	if (doit)
 	{
+		char	   *canon_val = guc_strdup(ERROR, newval);
+		char	   *tname;
+		char	   *fname;
+
+		canonicalize_path(canon_val);
+
+		tname = guc_malloc(ERROR, strlen(canon_val) + 12);		/* /pgstat.tmp */
+		sprintf(tname, "%s/pgstat.tmp", canon_val);
+		fname = guc_malloc(ERROR, strlen(canon_val) + 13);		/* /pgstat.stat */
+		sprintf(fname, "%s/pgstat.stat", canon_val);
+
 		if (pgstat_stat_tmpname)
 			free(pgstat_stat_tmpname);
+		pgstat_stat_tmpname = tname;
 		if (pgstat_stat_filename)
 			free(pgstat_stat_filename);
+		pgstat_stat_filename = fname;
 
-		pgstat_stat_tmpname = guc_malloc(FATAL, strlen(newval) + 12);  /* /pgstat.tmp */
-		pgstat_stat_filename = guc_malloc(FATAL, strlen(newval) + 13); /* /pgstat.stat */
-
-		sprintf(pgstat_stat_tmpname, "%s/pgstat.tmp", newval);
-		sprintf(pgstat_stat_filename, "%s/pgstat.stat", newval);
+		return canon_val;
 	}
+	else
+		return newval;
+}
 
-	return newval;
+static const char *
+assign_application_name(const char *newval, bool doit, GucSource source)
+{
+	if (doit)
+	{
+		/* Only allow clean ASCII chars in the application name */
+		char	   *repval = guc_strdup(ERROR, newval);
+		char	   *p;
+
+		for (p = repval; *p; p++)
+		{
+			if (*p < 32 || *p > 126)
+				*p = '?';
+		}
+
+		/* Update the pg_stat_activity view */
+		pgstat_report_appname(repval);
+
+		return repval;
+	}
+	else
+		return newval;
 }
 
 #include "guc-file.c"