/*-------------------------------------------------------------------- * guc.c * * Support for grand unified configuration scheme, including SET * command, configuration file, and command line options. * * This file contains the generic option processing infrastructure. * guc_funcs.c contains SQL-level functionality, including SET/SHOW * commands and various system-administration SQL functions. * guc_tables.c contains the arrays that define all the built-in * GUC variables. Code that implements variable-specific behavior * is scattered around the system in check, assign, and show hooks. * * See src/backend/utils/misc/README for more information. * * * Copyright (c) 2000-2025, PostgreSQL Global Development Group * Written by Peter Eisentraut . * * IDENTIFICATION * src/backend/utils/misc/guc.c * *-------------------------------------------------------------------- */ #include "postgres.h" #include #include #include #include #include "access/xact.h" #include "access/xlog.h" #include "catalog/objectaccess.h" #include "catalog/pg_authid.h" #include "catalog/pg_parameter_acl.h" #include "guc_internal.h" #include "libpq/pqformat.h" #include "libpq/protocol.h" #include "miscadmin.h" #include "parser/scansup.h" #include "port/pg_bitutils.h" #include "storage/fd.h" #include "storage/lwlock.h" #include "storage/shmem.h" #include "tcop/tcopprot.h" #include "utils/acl.h" #include "utils/builtins.h" #include "utils/conffiles.h" #include "utils/guc_tables.h" #include "utils/memutils.h" #include "utils/timestamp.h" #define CONFIG_FILENAME "postgresql.conf" #define HBA_FILENAME "pg_hba.conf" #define IDENT_FILENAME "pg_ident.conf" #ifdef EXEC_BACKEND #define CONFIG_EXEC_PARAMS "global/config_exec_params" #define CONFIG_EXEC_PARAMS_NEW "global/config_exec_params.new" #endif /* * Precision with which REAL type guc values are to be printed for GUC * serialization. */ #define REALTYPE_PRECISION 17 /* * Safe search path when executing code as the table owner, such as during * maintenance operations. */ #define GUC_SAFE_SEARCH_PATH "pg_catalog, pg_temp" static int GUC_check_errcode_value; static List *reserved_class_prefix = NIL; /* global variables for check hook support */ char *GUC_check_errmsg_string; char *GUC_check_errdetail_string; char *GUC_check_errhint_string; /* * Unit conversion tables. * * There are two tables, one for memory units, and another for time units. * For each supported conversion from one unit to another, we have an entry * in the table. * * To keep things simple, and to avoid possible roundoff error, * conversions are never chained. There needs to be a direct conversion * between all units (of the same type). * * The conversions for each base unit must be kept in order from greatest to * smallest human-friendly unit; convert_xxx_from_base_unit() rely on that. * (The order of the base-unit groups does not matter.) */ #define MAX_UNIT_LEN 3 /* length of longest recognized unit string */ typedef struct { char unit[MAX_UNIT_LEN + 1]; /* unit, as a string, like "kB" or * "min" */ int base_unit; /* GUC_UNIT_XXX */ double multiplier; /* Factor for converting unit -> base_unit */ } unit_conversion; /* Ensure that the constants in the tables don't overflow or underflow */ #if BLCKSZ < 1024 || BLCKSZ > (1024*1024) #error BLCKSZ must be between 1KB and 1MB #endif #if XLOG_BLCKSZ < 1024 || XLOG_BLCKSZ > (1024*1024) #error XLOG_BLCKSZ must be between 1KB and 1MB #endif static const char *const memory_units_hint = gettext_noop("Valid units for this parameter are \"B\", \"kB\", \"MB\", \"GB\", and \"TB\"."); static const unit_conversion memory_unit_conversion_table[] = { {"TB", GUC_UNIT_BYTE, 1024.0 * 1024.0 * 1024.0 * 1024.0}, {"GB", GUC_UNIT_BYTE, 1024.0 * 1024.0 * 1024.0}, {"MB", GUC_UNIT_BYTE, 1024.0 * 1024.0}, {"kB", GUC_UNIT_BYTE, 1024.0}, {"B", GUC_UNIT_BYTE, 1.0}, {"TB", GUC_UNIT_KB, 1024.0 * 1024.0 * 1024.0}, {"GB", GUC_UNIT_KB, 1024.0 * 1024.0}, {"MB", GUC_UNIT_KB, 1024.0}, {"kB", GUC_UNIT_KB, 1.0}, {"B", GUC_UNIT_KB, 1.0 / 1024.0}, {"TB", GUC_UNIT_MB, 1024.0 * 1024.0}, {"GB", GUC_UNIT_MB, 1024.0}, {"MB", GUC_UNIT_MB, 1.0}, {"kB", GUC_UNIT_MB, 1.0 / 1024.0}, {"B", GUC_UNIT_MB, 1.0 / (1024.0 * 1024.0)}, {"TB", GUC_UNIT_BLOCKS, (1024.0 * 1024.0 * 1024.0) / (BLCKSZ / 1024)}, {"GB", GUC_UNIT_BLOCKS, (1024.0 * 1024.0) / (BLCKSZ / 1024)}, {"MB", GUC_UNIT_BLOCKS, 1024.0 / (BLCKSZ / 1024)}, {"kB", GUC_UNIT_BLOCKS, 1.0 / (BLCKSZ / 1024)}, {"B", GUC_UNIT_BLOCKS, 1.0 / BLCKSZ}, {"TB", GUC_UNIT_XBLOCKS, (1024.0 * 1024.0 * 1024.0) / (XLOG_BLCKSZ / 1024)}, {"GB", GUC_UNIT_XBLOCKS, (1024.0 * 1024.0) / (XLOG_BLCKSZ / 1024)}, {"MB", GUC_UNIT_XBLOCKS, 1024.0 / (XLOG_BLCKSZ / 1024)}, {"kB", GUC_UNIT_XBLOCKS, 1.0 / (XLOG_BLCKSZ / 1024)}, {"B", GUC_UNIT_XBLOCKS, 1.0 / XLOG_BLCKSZ}, {""} /* end of table marker */ }; static const char *const time_units_hint = gettext_noop("Valid units for this parameter are \"us\", \"ms\", \"s\", \"min\", \"h\", and \"d\"."); static const unit_conversion time_unit_conversion_table[] = { {"d", GUC_UNIT_MS, 1000 * 60 * 60 * 24}, {"h", GUC_UNIT_MS, 1000 * 60 * 60}, {"min", GUC_UNIT_MS, 1000 * 60}, {"s", GUC_UNIT_MS, 1000}, {"ms", GUC_UNIT_MS, 1}, {"us", GUC_UNIT_MS, 1.0 / 1000}, {"d", GUC_UNIT_S, 60 * 60 * 24}, {"h", GUC_UNIT_S, 60 * 60}, {"min", GUC_UNIT_S, 60}, {"s", GUC_UNIT_S, 1}, {"ms", GUC_UNIT_S, 1.0 / 1000}, {"us", GUC_UNIT_S, 1.0 / (1000 * 1000)}, {"d", GUC_UNIT_MIN, 60 * 24}, {"h", GUC_UNIT_MIN, 60}, {"min", GUC_UNIT_MIN, 1}, {"s", GUC_UNIT_MIN, 1.0 / 60}, {"ms", GUC_UNIT_MIN, 1.0 / (1000 * 60)}, {"us", GUC_UNIT_MIN, 1.0 / (1000 * 1000 * 60)}, {""} /* end of table marker */ }; /* * To allow continued support of obsolete names for GUC variables, we apply * the following mappings to any unrecognized name. Note that an old name * should be mapped to a new one only if the new variable has very similar * semantics to the old. */ static const char *const map_old_guc_names[] = { "sort_mem", "work_mem", "vacuum_mem", "maintenance_work_mem", "ssl_ecdh_curve", "ssl_groups", NULL }; /* Memory context holding all GUC-related data */ static MemoryContext GUCMemoryContext; /* * We use a dynahash table to look up GUCs by name, or to iterate through * all the GUCs. The gucname field is redundant with gucvar->name, but * dynahash makes it too painful to not store the hash key separately. */ typedef struct { const char *gucname; /* hash key */ struct config_generic *gucvar; /* -> GUC's defining structure */ } GUCHashEntry; static HTAB *guc_hashtab; /* entries are GUCHashEntrys */ /* * In addition to the hash table, variables having certain properties are * linked into these lists, so that we can find them without scanning the * whole hash table. In most applications, only a small fraction of the * GUCs appear in these lists at any given time. The usage of the stack * and report lists is stylized enough that they can be slists, but the * nondef list has to be a dlist to avoid O(N) deletes in common cases. */ static dlist_head guc_nondef_list; /* list of variables that have source * different from PGC_S_DEFAULT */ static slist_head guc_stack_list; /* list of variables that have non-NULL * stack */ static slist_head guc_report_list; /* list of variables that have the * GUC_NEEDS_REPORT bit set in status */ static bool reporting_enabled; /* true to enable GUC_REPORT */ static int GUCNestLevel = 0; /* 1 when in main transaction */ static int guc_var_compare(const void *a, const void *b); static uint32 guc_name_hash(const void *key, Size keysize); static int guc_name_match(const void *key1, const void *key2, Size keysize); static void InitializeGUCOptionsFromEnvironment(void); static void InitializeOneGUCOption(struct config_generic *gconf); static void RemoveGUCFromLists(struct config_generic *gconf); static void set_guc_source(struct config_generic *gconf, GucSource newsource); static void pg_timezone_abbrev_initialize(void); static void push_old_value(struct config_generic *gconf, GucAction action); static void ReportGUCOption(struct config_generic *record); static void set_config_sourcefile(const char *name, char *sourcefile, int sourceline); static void reapply_stacked_values(struct config_generic *variable, struct config_string *pHolder, GucStack *stack, const char *curvalue, GucContext curscontext, GucSource cursource, Oid cursrole); static bool validate_option_array_item(const char *name, const char *value, bool skipIfNoPermissions); static void write_auto_conf_file(int fd, const char *filename, ConfigVariable *head); static void replace_auto_config_value(ConfigVariable **head_p, ConfigVariable **tail_p, const char *name, const char *value); static bool valid_custom_variable_name(const char *name); static bool assignable_custom_variable_name(const char *name, bool skip_errors, int elevel); static void do_serialize(char **destptr, Size *maxbytes, const char *fmt,...) pg_attribute_printf(3, 4); static bool call_bool_check_hook(struct config_bool *conf, bool *newval, void **extra, GucSource source, int elevel); static bool call_int_check_hook(struct config_int *conf, int *newval, void **extra, GucSource source, int elevel); static bool call_real_check_hook(struct config_real *conf, double *newval, void **extra, GucSource source, int elevel); static bool call_string_check_hook(struct config_string *conf, char **newval, void **extra, GucSource source, int elevel); static bool call_enum_check_hook(struct config_enum *conf, int *newval, void **extra, GucSource source, int elevel); /* * This function handles both actual config file (re)loads and execution of * show_all_file_settings() (i.e., the pg_file_settings view). In the latter * case we don't apply any of the settings, but we make all the usual validity * checks, and we return the ConfigVariable list so that it can be printed out * by show_all_file_settings(). */ ConfigVariable * ProcessConfigFileInternal(GucContext context, bool applySettings, int elevel) { bool error = false; bool applying = false; const char *ConfFileWithError; ConfigVariable *item, *head, *tail; HASH_SEQ_STATUS status; GUCHashEntry *hentry; /* Parse the main config file into a list of option names and values */ ConfFileWithError = ConfigFileName; head = tail = NULL; if (!ParseConfigFile(ConfigFileName, true, NULL, 0, CONF_FILE_START_DEPTH, elevel, &head, &tail)) { /* Syntax error(s) detected in the file, so bail out */ error = true; goto bail_out; } /* * Parse the PG_AUTOCONF_FILENAME file, if present, after the main file to * replace any parameters set by ALTER SYSTEM command. Because this file * is in the data directory, we can't read it until the DataDir has been * set. */ if (DataDir) { if (!ParseConfigFile(PG_AUTOCONF_FILENAME, false, NULL, 0, CONF_FILE_START_DEPTH, elevel, &head, &tail)) { /* Syntax error(s) detected in the file, so bail out */ error = true; ConfFileWithError = PG_AUTOCONF_FILENAME; goto bail_out; } } else { /* * If DataDir is not set, the PG_AUTOCONF_FILENAME file cannot be * read. In this case, we don't want to accept any settings but * data_directory from postgresql.conf, because they might be * overwritten with settings in the PG_AUTOCONF_FILENAME file which * will be read later. OTOH, since data_directory isn't allowed in the * PG_AUTOCONF_FILENAME file, it will never be overwritten later. */ ConfigVariable *newlist = NULL; /* * Prune all items except the last "data_directory" from the list. */ for (item = head; item; item = item->next) { if (!item->ignore && strcmp(item->name, "data_directory") == 0) newlist = item; } if (newlist) newlist->next = NULL; head = tail = newlist; /* * Quick exit if data_directory is not present in file. * * We need not do any further processing, in particular we don't set * PgReloadTime; that will be set soon by subsequent full loading of * the config file. */ if (head == NULL) goto bail_out; } /* * Mark all extant GUC variables as not present in the config file. We * need this so that we can tell below which ones have been removed from * the file since we last processed it. */ hash_seq_init(&status, guc_hashtab); while ((hentry = (GUCHashEntry *) hash_seq_search(&status)) != NULL) { struct config_generic *gconf = hentry->gucvar; gconf->status &= ~GUC_IS_IN_FILE; } /* * Check if all the supplied option names are valid, as an additional * quasi-syntactic check on the validity of the config file. It is * important that the postmaster and all backends agree on the results of * this phase, else we will have strange inconsistencies about which * processes accept a config file update and which don't. Hence, unknown * custom variable names have to be accepted without complaint. For the * same reason, we don't attempt to validate the options' values here. * * In addition, the GUC_IS_IN_FILE flag is set on each existing GUC * variable mentioned in the file; and we detect duplicate entries in the * file and mark the earlier occurrences as ignorable. */ for (item = head; item; item = item->next) { struct config_generic *record; /* Ignore anything already marked as ignorable */ if (item->ignore) continue; /* * Try to find the variable; but do not create a custom placeholder if * it's not there already. */ record = find_option(item->name, false, true, elevel); if (record) { /* If it's already marked, then this is a duplicate entry */ if (record->status & GUC_IS_IN_FILE) { /* * Mark the earlier occurrence(s) as dead/ignorable. We could * avoid the O(N^2) behavior here with some additional state, * but it seems unlikely to be worth the trouble. */ ConfigVariable *pitem; for (pitem = head; pitem != item; pitem = pitem->next) { if (!pitem->ignore && strcmp(pitem->name, item->name) == 0) pitem->ignore = true; } } /* Now mark it as present in file */ record->status |= GUC_IS_IN_FILE; } else if (!valid_custom_variable_name(item->name)) { /* Invalid non-custom variable, so complain */ ereport(elevel, (errcode(ERRCODE_UNDEFINED_OBJECT), errmsg("unrecognized configuration parameter \"%s\" in file \"%s\" line %d", item->name, item->filename, item->sourceline))); item->errmsg = pstrdup("unrecognized configuration parameter"); error = true; ConfFileWithError = item->filename; } } /* * If we've detected any errors so far, we don't want to risk applying any * changes. */ if (error) goto bail_out; /* Otherwise, set flag that we're beginning to apply changes */ applying = true; /* * Check for variables having been removed from the config file, and * revert their reset values (and perhaps also effective values) to the * boot-time defaults. If such a variable can't be changed after startup, * report that and continue. */ hash_seq_init(&status, guc_hashtab); while ((hentry = (GUCHashEntry *) hash_seq_search(&status)) != NULL) { struct config_generic *gconf = hentry->gucvar; GucStack *stack; if (gconf->reset_source != PGC_S_FILE || (gconf->status & GUC_IS_IN_FILE)) continue; if (gconf->context < PGC_SIGHUP) { /* The removal can't be effective without a restart */ gconf->status |= GUC_PENDING_RESTART; ereport(elevel, (errcode(ERRCODE_CANT_CHANGE_RUNTIME_PARAM), errmsg("parameter \"%s\" cannot be changed without restarting the server", gconf->name))); record_config_file_error(psprintf("parameter \"%s\" cannot be changed without restarting the server", gconf->name), NULL, 0, &head, &tail); error = true; continue; } /* No more to do if we're just doing show_all_file_settings() */ if (!applySettings) continue; /* * Reset any "file" sources to "default", else set_config_option will * not override those settings. */ if (gconf->reset_source == PGC_S_FILE) gconf->reset_source = PGC_S_DEFAULT; if (gconf->source == PGC_S_FILE) set_guc_source(gconf, PGC_S_DEFAULT); for (stack = gconf->stack; stack; stack = stack->prev) { if (stack->source == PGC_S_FILE) stack->source = PGC_S_DEFAULT; } /* Now we can re-apply the wired-in default (i.e., the boot_val) */ if (set_config_option(gconf->name, NULL, context, PGC_S_DEFAULT, GUC_ACTION_SET, true, 0, false) > 0) { /* Log the change if appropriate */ if (context == PGC_SIGHUP) ereport(elevel, (errmsg("parameter \"%s\" removed from configuration file, reset to default", gconf->name))); } } /* * Restore any variables determined by environment variables or * dynamically-computed defaults. This is a no-op except in the case * where one of these had been in the config file and is now removed. * * In particular, we *must not* do this during the postmaster's initial * loading of the file, since the timezone functions in particular should * be run only after initialization is complete. * * XXX this is an unmaintainable crock, because we have to know how to set * (or at least what to call to set) every non-PGC_INTERNAL variable that * could potentially have PGC_S_DYNAMIC_DEFAULT or PGC_S_ENV_VAR source. */ if (context == PGC_SIGHUP && applySettings) { InitializeGUCOptionsFromEnvironment(); pg_timezone_abbrev_initialize(); /* this selects SQL_ASCII in processes not connected to a database */ SetConfigOption("client_encoding", GetDatabaseEncodingName(), PGC_BACKEND, PGC_S_DYNAMIC_DEFAULT); } /* * Now apply the values from the config file. */ for (item = head; item; item = item->next) { char *pre_value = NULL; int scres; /* Ignore anything marked as ignorable */ if (item->ignore) continue; /* In SIGHUP cases in the postmaster, we want to report changes */ if (context == PGC_SIGHUP && applySettings && !IsUnderPostmaster) { const char *preval = GetConfigOption(item->name, true, false); /* If option doesn't exist yet or is NULL, treat as empty string */ if (!preval) preval = ""; /* must dup, else might have dangling pointer below */ pre_value = pstrdup(preval); } scres = set_config_option(item->name, item->value, context, PGC_S_FILE, GUC_ACTION_SET, applySettings, 0, false); if (scres > 0) { /* variable was updated, so log the change if appropriate */ if (pre_value) { const char *post_value = GetConfigOption(item->name, true, false); if (!post_value) post_value = ""; if (strcmp(pre_value, post_value) != 0) ereport(elevel, (errmsg("parameter \"%s\" changed to \"%s\"", item->name, item->value))); } item->applied = true; } else if (scres == 0) { error = true; item->errmsg = pstrdup("setting could not be applied"); ConfFileWithError = item->filename; } else { /* no error, but variable's active value was not changed */ item->applied = true; } /* * We should update source location unless there was an error, since * even if the active value didn't change, the reset value might have. * (In the postmaster, there won't be a difference, but it does matter * in backends.) */ if (scres != 0 && applySettings) set_config_sourcefile(item->name, item->filename, item->sourceline); if (pre_value) pfree(pre_value); } /* Remember when we last successfully loaded the config file. */ if (applySettings) PgReloadTime = GetCurrentTimestamp(); bail_out: if (error && applySettings) { /* During postmaster startup, any error is fatal */ if (context == PGC_POSTMASTER) ereport(ERROR, (errcode(ERRCODE_CONFIG_FILE_ERROR), errmsg("configuration file \"%s\" contains errors", ConfFileWithError))); else if (applying) ereport(elevel, (errcode(ERRCODE_CONFIG_FILE_ERROR), errmsg("configuration file \"%s\" contains errors; unaffected changes were applied", ConfFileWithError))); else ereport(elevel, (errcode(ERRCODE_CONFIG_FILE_ERROR), errmsg("configuration file \"%s\" contains errors; no changes were applied", ConfFileWithError))); } /* Successful or otherwise, return the collected data list */ return head; } /* * Some infrastructure for GUC-related memory allocation * * These functions are generally modeled on libc's malloc/realloc/etc, * but any OOM issue is reported at the specified elevel. * (Thus, control returns only if that's less than ERROR.) */ void * guc_malloc(int elevel, size_t size) { void *data; data = MemoryContextAllocExtended(GUCMemoryContext, size, MCXT_ALLOC_NO_OOM); if (unlikely(data == NULL)) ereport(elevel, (errcode(ERRCODE_OUT_OF_MEMORY), errmsg("out of memory"))); return data; } void * guc_realloc(int elevel, void *old, size_t size) { void *data; if (old != NULL) { /* This is to help catch old code that malloc's GUC data. */ Assert(GetMemoryChunkContext(old) == GUCMemoryContext); data = repalloc_extended(old, size, MCXT_ALLOC_NO_OOM); } else { /* Like realloc(3), but not like repalloc(), we allow old == NULL. */ data = MemoryContextAllocExtended(GUCMemoryContext, size, MCXT_ALLOC_NO_OOM); } if (unlikely(data == NULL)) ereport(elevel, (errcode(ERRCODE_OUT_OF_MEMORY), errmsg("out of memory"))); return data; } char * guc_strdup(int elevel, const char *src) { char *data; size_t len = strlen(src) + 1; data = guc_malloc(elevel, len); if (likely(data != NULL)) memcpy(data, src, len); return data; } void guc_free(void *ptr) { /* * Historically, GUC-related code has relied heavily on the ability to do * free(NULL), so we allow that here even though pfree() doesn't. */ if (ptr != NULL) { /* This is to help catch old code that malloc's GUC data. */ Assert(GetMemoryChunkContext(ptr) == GUCMemoryContext); pfree(ptr); } } /* * Detect whether strval is referenced anywhere in a GUC string item */ static bool string_field_used(struct config_string *conf, char *strval) { GucStack *stack; if (strval == *(conf->variable) || strval == conf->reset_val || strval == conf->boot_val) return true; for (stack = conf->gen.stack; stack; stack = stack->prev) { if (strval == stack->prior.val.stringval || strval == stack->masked.val.stringval) return true; } return false; } /* * Support for assigning to a field of a string GUC item. Free the prior * value if it's not referenced anywhere else in the item (including stacked * states). */ static void set_string_field(struct config_string *conf, char **field, char *newval) { char *oldval = *field; /* Do the assignment */ *field = newval; /* Free old value if it's not NULL and isn't referenced anymore */ if (oldval && !string_field_used(conf, oldval)) guc_free(oldval); } /* * Detect whether an "extra" struct is referenced anywhere in a GUC item */ static bool extra_field_used(struct config_generic *gconf, void *extra) { GucStack *stack; if (extra == gconf->extra) return true; switch (gconf->vartype) { case PGC_BOOL: if (extra == ((struct config_bool *) gconf)->reset_extra) return true; break; case PGC_INT: if (extra == ((struct config_int *) gconf)->reset_extra) return true; break; case PGC_REAL: if (extra == ((struct config_real *) gconf)->reset_extra) return true; break; case PGC_STRING: if (extra == ((struct config_string *) gconf)->reset_extra) return true; break; case PGC_ENUM: if (extra == ((struct config_enum *) gconf)->reset_extra) return true; break; } for (stack = gconf->stack; stack; stack = stack->prev) { if (extra == stack->prior.extra || extra == stack->masked.extra) return true; } return false; } /* * Support for assigning to an "extra" field of a GUC item. Free the prior * value if it's not referenced anywhere else in the item (including stacked * states). */ static void set_extra_field(struct config_generic *gconf, void **field, void *newval) { void *oldval = *field; /* Do the assignment */ *field = newval; /* Free old value if it's not NULL and isn't referenced anymore */ if (oldval && !extra_field_used(gconf, oldval)) guc_free(oldval); } /* * Support for copying a variable's active value into a stack entry. * The "extra" field associated with the active value is copied, too. * * NB: be sure stringval and extra fields of a new stack entry are * initialized to NULL before this is used, else we'll try to guc_free() them. */ static void set_stack_value(struct config_generic *gconf, config_var_value *val) { switch (gconf->vartype) { case PGC_BOOL: val->val.boolval = *((struct config_bool *) gconf)->variable; break; case PGC_INT: val->val.intval = *((struct config_int *) gconf)->variable; break; case PGC_REAL: val->val.realval = *((struct config_real *) gconf)->variable; break; case PGC_STRING: set_string_field((struct config_string *) gconf, &(val->val.stringval), *((struct config_string *) gconf)->variable); break; case PGC_ENUM: val->val.enumval = *((struct config_enum *) gconf)->variable; break; } set_extra_field(gconf, &(val->extra), gconf->extra); } /* * Support for discarding a no-longer-needed value in a stack entry. * The "extra" field associated with the stack entry is cleared, too. */ static void discard_stack_value(struct config_generic *gconf, config_var_value *val) { switch (gconf->vartype) { case PGC_BOOL: case PGC_INT: case PGC_REAL: case PGC_ENUM: /* no need to do anything */ break; case PGC_STRING: set_string_field((struct config_string *) gconf, &(val->val.stringval), NULL); break; } set_extra_field(gconf, &(val->extra), NULL); } /* * Fetch a palloc'd, sorted array of GUC struct pointers * * The array length is returned into *num_vars. */ struct config_generic ** get_guc_variables(int *num_vars) { struct config_generic **result; HASH_SEQ_STATUS status; GUCHashEntry *hentry; int i; *num_vars = hash_get_num_entries(guc_hashtab); result = palloc(sizeof(struct config_generic *) * *num_vars); /* Extract pointers from the hash table */ i = 0; hash_seq_init(&status, guc_hashtab); while ((hentry = (GUCHashEntry *) hash_seq_search(&status)) != NULL) result[i++] = hentry->gucvar; Assert(i == *num_vars); /* Sort by name */ qsort(result, *num_vars, sizeof(struct config_generic *), guc_var_compare); return result; } /* * Build the GUC hash table. This is split out so that help_config.c can * extract all the variables without running all of InitializeGUCOptions. * It's not meant for use anyplace else. */ void build_guc_variables(void) { int size_vars; int num_vars = 0; HASHCTL hash_ctl; GUCHashEntry *hentry; bool found; int i; /* * Create the memory context that will hold all GUC-related data. */ Assert(GUCMemoryContext == NULL); GUCMemoryContext = AllocSetContextCreate(TopMemoryContext, "GUCMemoryContext", ALLOCSET_DEFAULT_SIZES); /* * Count all the built-in variables, and set their vartypes correctly. */ for (i = 0; ConfigureNamesBool[i].gen.name; i++) { struct config_bool *conf = &ConfigureNamesBool[i]; /* Rather than requiring vartype to be filled in by hand, do this: */ conf->gen.vartype = PGC_BOOL; num_vars++; } for (i = 0; ConfigureNamesInt[i].gen.name; i++) { struct config_int *conf = &ConfigureNamesInt[i]; conf->gen.vartype = PGC_INT; num_vars++; } for (i = 0; ConfigureNamesReal[i].gen.name; i++) { struct config_real *conf = &ConfigureNamesReal[i]; conf->gen.vartype = PGC_REAL; num_vars++; } for (i = 0; ConfigureNamesString[i].gen.name; i++) { struct config_string *conf = &ConfigureNamesString[i]; conf->gen.vartype = PGC_STRING; num_vars++; } for (i = 0; ConfigureNamesEnum[i].gen.name; i++) { struct config_enum *conf = &ConfigureNamesEnum[i]; conf->gen.vartype = PGC_ENUM; num_vars++; } /* * Create hash table with 20% slack */ size_vars = num_vars + num_vars / 4; hash_ctl.keysize = sizeof(char *); hash_ctl.entrysize = sizeof(GUCHashEntry); hash_ctl.hash = guc_name_hash; hash_ctl.match = guc_name_match; hash_ctl.hcxt = GUCMemoryContext; guc_hashtab = hash_create("GUC hash table", size_vars, &hash_ctl, HASH_ELEM | HASH_FUNCTION | HASH_COMPARE | HASH_CONTEXT); for (i = 0; ConfigureNamesBool[i].gen.name; i++) { struct config_generic *gucvar = &ConfigureNamesBool[i].gen; hentry = (GUCHashEntry *) hash_search(guc_hashtab, &gucvar->name, HASH_ENTER, &found); Assert(!found); hentry->gucvar = gucvar; } for (i = 0; ConfigureNamesInt[i].gen.name; i++) { struct config_generic *gucvar = &ConfigureNamesInt[i].gen; hentry = (GUCHashEntry *) hash_search(guc_hashtab, &gucvar->name, HASH_ENTER, &found); Assert(!found); hentry->gucvar = gucvar; } for (i = 0; ConfigureNamesReal[i].gen.name; i++) { struct config_generic *gucvar = &ConfigureNamesReal[i].gen; hentry = (GUCHashEntry *) hash_search(guc_hashtab, &gucvar->name, HASH_ENTER, &found); Assert(!found); hentry->gucvar = gucvar; } for (i = 0; ConfigureNamesString[i].gen.name; i++) { struct config_generic *gucvar = &ConfigureNamesString[i].gen; hentry = (GUCHashEntry *) hash_search(guc_hashtab, &gucvar->name, HASH_ENTER, &found); Assert(!found); hentry->gucvar = gucvar; } for (i = 0; ConfigureNamesEnum[i].gen.name; i++) { struct config_generic *gucvar = &ConfigureNamesEnum[i].gen; hentry = (GUCHashEntry *) hash_search(guc_hashtab, &gucvar->name, HASH_ENTER, &found); Assert(!found); hentry->gucvar = gucvar; } Assert(num_vars == hash_get_num_entries(guc_hashtab)); } /* * Add a new GUC variable to the hash of known variables. The * hash is expanded if needed. */ static bool add_guc_variable(struct config_generic *var, int elevel) { GUCHashEntry *hentry; bool found; hentry = (GUCHashEntry *) hash_search(guc_hashtab, &var->name, HASH_ENTER_NULL, &found); if (unlikely(hentry == NULL)) { ereport(elevel, (errcode(ERRCODE_OUT_OF_MEMORY), errmsg("out of memory"))); return false; /* out of memory */ } Assert(!found); hentry->gucvar = var; return true; } /* * Decide whether a proposed custom variable name is allowed. * * It must be two or more identifiers separated by dots, where the rules * for what is an identifier agree with scan.l. (If you change this rule, * adjust the errdetail in assignable_custom_variable_name().) */ static bool valid_custom_variable_name(const char *name) { bool saw_sep = false; bool name_start = true; for (const char *p = name; *p; p++) { if (*p == GUC_QUALIFIER_SEPARATOR) { if (name_start) return false; /* empty name component */ saw_sep = true; name_start = true; } else if (strchr("ABCDEFGHIJKLMNOPQRSTUVWXYZ" "abcdefghijklmnopqrstuvwxyz_", *p) != NULL || IS_HIGHBIT_SET(*p)) { /* okay as first or non-first character */ name_start = false; } else if (!name_start && strchr("0123456789$", *p) != NULL) /* okay as non-first character */ ; else return false; } if (name_start) return false; /* empty name component */ /* OK if we found at least one separator */ return saw_sep; } /* * Decide whether an unrecognized variable name is allowed to be SET. * * It must pass the syntactic rules of valid_custom_variable_name(), * and it must not be in any namespace already reserved by an extension. * (We make this separate from valid_custom_variable_name() because we don't * apply the reserved-namespace test when reading configuration files.) * * If valid, return true. Otherwise, return false if skip_errors is true, * else throw a suitable error at the specified elevel (and return false * if that's less than ERROR). */ static bool assignable_custom_variable_name(const char *name, bool skip_errors, int elevel) { /* If there's no separator, it can't be a custom variable */ const char *sep = strchr(name, GUC_QUALIFIER_SEPARATOR); if (sep != NULL) { size_t classLen = sep - name; ListCell *lc; /* The name must be syntactically acceptable ... */ if (!valid_custom_variable_name(name)) { if (!skip_errors) ereport(elevel, (errcode(ERRCODE_INVALID_NAME), errmsg("invalid configuration parameter name \"%s\"", name), errdetail("Custom parameter names must be two or more simple identifiers separated by dots."))); return false; } /* ... and it must not match any previously-reserved prefix */ foreach(lc, reserved_class_prefix) { const char *rcprefix = lfirst(lc); if (strlen(rcprefix) == classLen && strncmp(name, rcprefix, classLen) == 0) { if (!skip_errors) ereport(elevel, (errcode(ERRCODE_INVALID_NAME), errmsg("invalid configuration parameter name \"%s\"", name), errdetail("\"%s\" is a reserved prefix.", rcprefix))); return false; } } /* OK to create it */ return true; } /* Unrecognized single-part name */ if (!skip_errors) ereport(elevel, (errcode(ERRCODE_UNDEFINED_OBJECT), errmsg("unrecognized configuration parameter \"%s\"", name))); return false; } /* * Create and add a placeholder variable for a custom variable name. */ static struct config_generic * add_placeholder_variable(const char *name, int elevel) { size_t sz = sizeof(struct config_string) + sizeof(char *); struct config_string *var; struct config_generic *gen; var = (struct config_string *) guc_malloc(elevel, sz); if (var == NULL) return NULL; memset(var, 0, sz); gen = &var->gen; gen->name = guc_strdup(elevel, name); if (gen->name == NULL) { guc_free(var); return NULL; } gen->context = PGC_USERSET; gen->group = CUSTOM_OPTIONS; gen->short_desc = "GUC placeholder variable"; gen->flags = GUC_NO_SHOW_ALL | GUC_NOT_IN_SAMPLE | GUC_CUSTOM_PLACEHOLDER; gen->vartype = PGC_STRING; /* * The char* is allocated at the end of the struct since we have no * 'static' place to point to. Note that the current value, as well as * the boot and reset values, start out NULL. */ var->variable = (char **) (var + 1); if (!add_guc_variable((struct config_generic *) var, elevel)) { guc_free(unconstify(char *, gen->name)); guc_free(var); return NULL; } return gen; } /* * Look up option "name". If it exists, return a pointer to its record. * Otherwise, if create_placeholders is true and name is a valid-looking * custom variable name, we'll create and return a placeholder record. * Otherwise, if skip_errors is true, then we silently return NULL for * an unrecognized or invalid name. Otherwise, the error is reported at * error level elevel (and we return NULL if that's less than ERROR). * * Note: internal errors, primarily out-of-memory, draw an elevel-level * report and NULL return regardless of skip_errors. Hence, callers must * handle a NULL return whenever elevel < ERROR, but they should not need * to emit any additional error message. (In practice, internal errors * can only happen when create_placeholders is true, so callers passing * false need not think terribly hard about this.) */ struct config_generic * find_option(const char *name, bool create_placeholders, bool skip_errors, int elevel) { GUCHashEntry *hentry; int i; Assert(name); /* Look it up using the hash table. */ hentry = (GUCHashEntry *) hash_search(guc_hashtab, &name, HASH_FIND, NULL); if (hentry) return hentry->gucvar; /* * See if the name is an obsolete name for a variable. We assume that the * set of supported old names is short enough that a brute-force search is * the best way. */ for (i = 0; map_old_guc_names[i] != NULL; i += 2) { if (guc_name_compare(name, map_old_guc_names[i]) == 0) return find_option(map_old_guc_names[i + 1], false, skip_errors, elevel); } if (create_placeholders) { /* * Check if the name is valid, and if so, add a placeholder. */ if (assignable_custom_variable_name(name, skip_errors, elevel)) return add_placeholder_variable(name, elevel); else return NULL; /* error message, if any, already emitted */ } /* Unknown name and we're not supposed to make a placeholder */ if (!skip_errors) ereport(elevel, (errcode(ERRCODE_UNDEFINED_OBJECT), errmsg("unrecognized configuration parameter \"%s\"", name))); return NULL; } /* * comparator for qsorting an array of GUC pointers */ static int guc_var_compare(const void *a, const void *b) { const char *namea = **(const char **const *) a; const char *nameb = **(const char **const *) b; return guc_name_compare(namea, nameb); } /* * the bare comparison function for GUC names */ int guc_name_compare(const char *namea, const char *nameb) { /* * The temptation to use strcasecmp() here must be resisted, because the * hash mapping has to remain stable across setlocale() calls. So, build * our own with a simple ASCII-only downcasing. */ while (*namea && *nameb) { char cha = *namea++; char chb = *nameb++; if (cha >= 'A' && cha <= 'Z') cha += 'a' - 'A'; if (chb >= 'A' && chb <= 'Z') chb += 'a' - 'A'; if (cha != chb) return cha - chb; } if (*namea) return 1; /* a is longer */ if (*nameb) return -1; /* b is longer */ return 0; } /* * Hash function that's compatible with guc_name_compare */ static uint32 guc_name_hash(const void *key, Size keysize) { uint32 result = 0; const char *name = *(const char *const *) key; while (*name) { char ch = *name++; /* Case-fold in the same way as guc_name_compare */ if (ch >= 'A' && ch <= 'Z') ch += 'a' - 'A'; /* Merge into hash ... not very bright, but it needn't be */ result = pg_rotate_left32(result, 5); result ^= (uint32) ch; } return result; } /* * Dynahash match function to use in guc_hashtab */ static int guc_name_match(const void *key1, const void *key2, Size keysize) { const char *name1 = *(const char *const *) key1; const char *name2 = *(const char *const *) key2; return guc_name_compare(name1, name2); } /* * Convert a GUC name to the form that should be used in pg_parameter_acl. * * We need to canonicalize entries since, for example, case should not be * significant. In addition, we apply the map_old_guc_names[] mapping so that * any obsolete names will be converted when stored in a new PG version. * Note however that this function does not verify legality of the name. * * The result is a palloc'd string. */ char * convert_GUC_name_for_parameter_acl(const char *name) { char *result; /* Apply old-GUC-name mapping. */ for (int i = 0; map_old_guc_names[i] != NULL; i += 2) { if (guc_name_compare(name, map_old_guc_names[i]) == 0) { name = map_old_guc_names[i + 1]; break; } } /* Apply case-folding that matches guc_name_compare(). */ result = pstrdup(name); for (char *ptr = result; *ptr != '\0'; ptr++) { char ch = *ptr; if (ch >= 'A' && ch <= 'Z') { ch += 'a' - 'A'; *ptr = ch; } } return result; } /* * Check whether we should allow creation of a pg_parameter_acl entry * for the given name. (This can be applied either before or after * canonicalizing it.) Throws error if not. */ void check_GUC_name_for_parameter_acl(const char *name) { /* OK if the GUC exists. */ if (find_option(name, false, true, DEBUG5) != NULL) return; /* Otherwise, it'd better be a valid custom GUC name. */ (void) assignable_custom_variable_name(name, false, ERROR); } /* * Routine in charge of checking various states of a GUC. * * This performs two sanity checks. First, it checks that the initial * value of a GUC is the same when declared and when loaded to prevent * anybody looking at the C declarations of these GUCs from being fooled by * mismatched values. Second, it checks for incorrect flag combinations. * * The following validation rules apply for the values: * bool - can be false, otherwise must be same as the boot_val * int - can be 0, otherwise must be same as the boot_val * real - can be 0.0, otherwise must be same as the boot_val * string - can be NULL, otherwise must be strcmp equal to the boot_val * enum - must be same as the boot_val */ #ifdef USE_ASSERT_CHECKING static bool check_GUC_init(struct config_generic *gconf) { /* Checks on values */ switch (gconf->vartype) { case PGC_BOOL: { struct config_bool *conf = (struct config_bool *) gconf; if (*conf->variable && !conf->boot_val) { elog(LOG, "GUC (PGC_BOOL) %s, boot_val=%d, C-var=%d", conf->gen.name, conf->boot_val, *conf->variable); return false; } break; } case PGC_INT: { struct config_int *conf = (struct config_int *) gconf; if (*conf->variable != 0 && *conf->variable != conf->boot_val) { elog(LOG, "GUC (PGC_INT) %s, boot_val=%d, C-var=%d", conf->gen.name, conf->boot_val, *conf->variable); return false; } break; } case PGC_REAL: { struct config_real *conf = (struct config_real *) gconf; if (*conf->variable != 0.0 && *conf->variable != conf->boot_val) { elog(LOG, "GUC (PGC_REAL) %s, boot_val=%g, C-var=%g", conf->gen.name, conf->boot_val, *conf->variable); return false; } break; } case PGC_STRING: { struct config_string *conf = (struct config_string *) gconf; if (*conf->variable != NULL && (conf->boot_val == NULL || strcmp(*conf->variable, conf->boot_val) != 0)) { elog(LOG, "GUC (PGC_STRING) %s, boot_val=%s, C-var=%s", conf->gen.name, conf->boot_val ? conf->boot_val : "", *conf->variable); return false; } break; } case PGC_ENUM: { struct config_enum *conf = (struct config_enum *) gconf; if (*conf->variable != conf->boot_val) { elog(LOG, "GUC (PGC_ENUM) %s, boot_val=%d, C-var=%d", conf->gen.name, conf->boot_val, *conf->variable); return false; } break; } } /* Flag combinations */ /* * GUC_NO_SHOW_ALL requires GUC_NOT_IN_SAMPLE, as a parameter not part of * SHOW ALL should not be hidden in postgresql.conf.sample. */ if ((gconf->flags & GUC_NO_SHOW_ALL) && !(gconf->flags & GUC_NOT_IN_SAMPLE)) { elog(LOG, "GUC %s flags: NO_SHOW_ALL and !NOT_IN_SAMPLE", gconf->name); return false; } return true; } #endif /* * Initialize GUC options during program startup. * * Note that we cannot read the config file yet, since we have not yet * processed command-line switches. */ void InitializeGUCOptions(void) { HASH_SEQ_STATUS status; GUCHashEntry *hentry; /* * Before log_line_prefix could possibly receive a nonempty setting, make * sure that timezone processing is minimally alive (see elog.c). */ pg_timezone_initialize(); /* * Create GUCMemoryContext and build hash table of all GUC variables. */ build_guc_variables(); /* * Load all variables with their compiled-in defaults, and initialize * status fields as needed. */ hash_seq_init(&status, guc_hashtab); while ((hentry = (GUCHashEntry *) hash_seq_search(&status)) != NULL) { /* Check mapping between initial and default value */ Assert(check_GUC_init(hentry->gucvar)); InitializeOneGUCOption(hentry->gucvar); } reporting_enabled = false; /* * Prevent any attempt to override the transaction modes from * non-interactive sources. */ SetConfigOption("transaction_isolation", "read committed", PGC_POSTMASTER, PGC_S_OVERRIDE); SetConfigOption("transaction_read_only", "no", PGC_POSTMASTER, PGC_S_OVERRIDE); SetConfigOption("transaction_deferrable", "no", PGC_POSTMASTER, PGC_S_OVERRIDE); /* * For historical reasons, some GUC parameters can receive defaults from * environment variables. Process those settings. */ InitializeGUCOptionsFromEnvironment(); } /* * Assign any GUC values that can come from the server's environment. * * This is called from InitializeGUCOptions, and also from ProcessConfigFile * to deal with the possibility that a setting has been removed from * postgresql.conf and should now get a value from the environment. * (The latter is a kludge that should probably go away someday; if so, * fold this back into InitializeGUCOptions.) */ static void InitializeGUCOptionsFromEnvironment(void) { char *env; ssize_t stack_rlimit; env = getenv("PGPORT"); if (env != NULL) SetConfigOption("port", env, PGC_POSTMASTER, PGC_S_ENV_VAR); env = getenv("PGDATESTYLE"); if (env != NULL) SetConfigOption("datestyle", env, PGC_POSTMASTER, PGC_S_ENV_VAR); env = getenv("PGCLIENTENCODING"); if (env != NULL) SetConfigOption("client_encoding", env, PGC_POSTMASTER, PGC_S_ENV_VAR); /* * rlimit isn't exactly an "environment variable", but it behaves about * the same. If we can identify the platform stack depth rlimit, increase * default stack depth setting up to whatever is safe (but at most 2MB). * Report the value's source as PGC_S_DYNAMIC_DEFAULT if it's 2MB, or as * PGC_S_ENV_VAR if it's reflecting the rlimit limit. */ stack_rlimit = get_stack_depth_rlimit(); if (stack_rlimit > 0) { ssize_t new_limit = (stack_rlimit - STACK_DEPTH_SLOP) / 1024; if (new_limit > 100) { GucSource source; char limbuf[16]; if (new_limit < 2048) source = PGC_S_ENV_VAR; else { new_limit = 2048; source = PGC_S_DYNAMIC_DEFAULT; } snprintf(limbuf, sizeof(limbuf), "%d", (int) new_limit); SetConfigOption("max_stack_depth", limbuf, PGC_POSTMASTER, source); } } } /* * Initialize one GUC option variable to its compiled-in default. * * Note: the reason for calling check_hooks is not that we think the boot_val * might fail, but that the hooks might wish to compute an "extra" struct. */ static void InitializeOneGUCOption(struct config_generic *gconf) { gconf->status = 0; gconf->source = PGC_S_DEFAULT; gconf->reset_source = PGC_S_DEFAULT; gconf->scontext = PGC_INTERNAL; gconf->reset_scontext = PGC_INTERNAL; gconf->srole = BOOTSTRAP_SUPERUSERID; gconf->reset_srole = BOOTSTRAP_SUPERUSERID; gconf->stack = NULL; gconf->extra = NULL; gconf->last_reported = NULL; gconf->sourcefile = NULL; gconf->sourceline = 0; switch (gconf->vartype) { case PGC_BOOL: { struct config_bool *conf = (struct config_bool *) gconf; bool newval = conf->boot_val; void *extra = NULL; if (!call_bool_check_hook(conf, &newval, &extra, PGC_S_DEFAULT, LOG)) elog(FATAL, "failed to initialize %s to %d", conf->gen.name, (int) newval); if (conf->assign_hook) conf->assign_hook(newval, extra); *conf->variable = conf->reset_val = newval; conf->gen.extra = conf->reset_extra = extra; break; } case PGC_INT: { struct config_int *conf = (struct config_int *) gconf; int newval = conf->boot_val; void *extra = NULL; Assert(newval >= conf->min); Assert(newval <= conf->max); if (!call_int_check_hook(conf, &newval, &extra, PGC_S_DEFAULT, LOG)) elog(FATAL, "failed to initialize %s to %d", conf->gen.name, newval); if (conf->assign_hook) conf->assign_hook(newval, extra); *conf->variable = conf->reset_val = newval; conf->gen.extra = conf->reset_extra = extra; break; } case PGC_REAL: { struct config_real *conf = (struct config_real *) gconf; double newval = conf->boot_val; void *extra = NULL; Assert(newval >= conf->min); Assert(newval <= conf->max); if (!call_real_check_hook(conf, &newval, &extra, PGC_S_DEFAULT, LOG)) elog(FATAL, "failed to initialize %s to %g", conf->gen.name, newval); if (conf->assign_hook) conf->assign_hook(newval, extra); *conf->variable = conf->reset_val = newval; conf->gen.extra = conf->reset_extra = extra; break; } case PGC_STRING: { struct config_string *conf = (struct config_string *) gconf; char *newval; void *extra = NULL; /* non-NULL boot_val must always get strdup'd */ if (conf->boot_val != NULL) newval = guc_strdup(FATAL, conf->boot_val); else newval = NULL; if (!call_string_check_hook(conf, &newval, &extra, PGC_S_DEFAULT, LOG)) elog(FATAL, "failed to initialize %s to \"%s\"", conf->gen.name, newval ? newval : ""); if (conf->assign_hook) conf->assign_hook(newval, extra); *conf->variable = conf->reset_val = newval; conf->gen.extra = conf->reset_extra = extra; break; } case PGC_ENUM: { struct config_enum *conf = (struct config_enum *) gconf; int newval = conf->boot_val; void *extra = NULL; if (!call_enum_check_hook(conf, &newval, &extra, PGC_S_DEFAULT, LOG)) elog(FATAL, "failed to initialize %s to %d", conf->gen.name, newval); if (conf->assign_hook) conf->assign_hook(newval, extra); *conf->variable = conf->reset_val = newval; conf->gen.extra = conf->reset_extra = extra; break; } } } /* * Summarily remove a GUC variable from any linked lists it's in. * * We use this in cases where the variable is about to be deleted or reset. * These aren't common operations, so it's okay if this is a bit slow. */ static void RemoveGUCFromLists(struct config_generic *gconf) { if (gconf->source != PGC_S_DEFAULT) dlist_delete(&gconf->nondef_link); if (gconf->stack != NULL) slist_delete(&guc_stack_list, &gconf->stack_link); if (gconf->status & GUC_NEEDS_REPORT) slist_delete(&guc_report_list, &gconf->report_link); } /* * Select the configuration files and data directory to be used, and * do the initial read of postgresql.conf. * * This is called after processing command-line switches. * userDoption is the -D switch value if any (NULL if unspecified). * progname is just for use in error messages. * * Returns true on success; on failure, prints a suitable error message * to stderr and returns false. */ bool SelectConfigFiles(const char *userDoption, const char *progname) { char *configdir; char *fname; bool fname_is_malloced; struct stat stat_buf; struct config_string *data_directory_rec; /* configdir is -D option, or $PGDATA if no -D */ if (userDoption) configdir = make_absolute_path(userDoption); else configdir = make_absolute_path(getenv("PGDATA")); if (configdir && stat(configdir, &stat_buf) != 0) { write_stderr("%s: could not access directory \"%s\": %m\n", progname, configdir); if (errno == ENOENT) write_stderr("Run initdb or pg_basebackup to initialize a PostgreSQL data directory.\n"); return false; } /* * Find the configuration file: if config_file was specified on the * command line, use it, else use configdir/postgresql.conf. In any case * ensure the result is an absolute path, so that it will be interpreted * the same way by future backends. */ if (ConfigFileName) { fname = make_absolute_path(ConfigFileName); fname_is_malloced = true; } else if (configdir) { fname = guc_malloc(FATAL, strlen(configdir) + strlen(CONFIG_FILENAME) + 2); sprintf(fname, "%s/%s", configdir, CONFIG_FILENAME); fname_is_malloced = false; } else { write_stderr("%s does not know where to find the server configuration file.\n" "You must specify the --config-file or -D invocation " "option or set the PGDATA environment variable.\n", progname); return false; } /* * Set the ConfigFileName GUC variable to its final value, ensuring that * it can't be overridden later. */ SetConfigOption("config_file", fname, PGC_POSTMASTER, PGC_S_OVERRIDE); if (fname_is_malloced) free(fname); else guc_free(fname); /* * Now read the config file for the first time. */ if (stat(ConfigFileName, &stat_buf) != 0) { write_stderr("%s: could not access the server configuration file \"%s\": %m\n", progname, ConfigFileName); free(configdir); return false; } /* * Read the configuration file for the first time. This time only the * data_directory parameter is picked up to determine the data directory, * so that we can read the PG_AUTOCONF_FILENAME file next time. */ ProcessConfigFile(PGC_POSTMASTER); /* * If the data_directory GUC variable has been set, use that as DataDir; * otherwise use configdir if set; else punt. * * Note: SetDataDir will copy and absolute-ize its argument, so we don't * have to. */ data_directory_rec = (struct config_string *) find_option("data_directory", false, false, PANIC); if (*data_directory_rec->variable) SetDataDir(*data_directory_rec->variable); else if (configdir) SetDataDir(configdir); else { write_stderr("%s does not know where to find the database system data.\n" "This can be specified as \"data_directory\" in \"%s\", " "or by the -D invocation option, or by the " "PGDATA environment variable.\n", progname, ConfigFileName); return false; } /* * Reflect the final DataDir value back into the data_directory GUC var. * (If you are wondering why we don't just make them a single variable, * it's because the EXEC_BACKEND case needs DataDir to be transmitted to * child backends specially. XXX is that still true? Given that we now * chdir to DataDir, EXEC_BACKEND can read the config file without knowing * DataDir in advance.) */ SetConfigOption("data_directory", DataDir, PGC_POSTMASTER, PGC_S_OVERRIDE); /* * Now read the config file a second time, allowing any settings in the * PG_AUTOCONF_FILENAME file to take effect. (This is pretty ugly, but * since we have to determine the DataDir before we can find the autoconf * file, the alternatives seem worse.) */ ProcessConfigFile(PGC_POSTMASTER); /* * If timezone_abbreviations wasn't set in the configuration file, install * the default value. We do it this way because we can't safely install a * "real" value until my_exec_path is set, which may not have happened * when InitializeGUCOptions runs, so the bootstrap default value cannot * be the real desired default. */ pg_timezone_abbrev_initialize(); /* * Figure out where pg_hba.conf is, and make sure the path is absolute. */ if (HbaFileName) { fname = make_absolute_path(HbaFileName); fname_is_malloced = true; } else if (configdir) { fname = guc_malloc(FATAL, strlen(configdir) + strlen(HBA_FILENAME) + 2); sprintf(fname, "%s/%s", configdir, HBA_FILENAME); fname_is_malloced = false; } else { write_stderr("%s does not know where to find the \"hba\" configuration file.\n" "This can be specified as \"hba_file\" in \"%s\", " "or by the -D invocation option, or by the " "PGDATA environment variable.\n", progname, ConfigFileName); return false; } SetConfigOption("hba_file", fname, PGC_POSTMASTER, PGC_S_OVERRIDE); if (fname_is_malloced) free(fname); else guc_free(fname); /* * Likewise for pg_ident.conf. */ if (IdentFileName) { fname = make_absolute_path(IdentFileName); fname_is_malloced = true; } else if (configdir) { fname = guc_malloc(FATAL, strlen(configdir) + strlen(IDENT_FILENAME) + 2); sprintf(fname, "%s/%s", configdir, IDENT_FILENAME); fname_is_malloced = false; } else { write_stderr("%s does not know where to find the \"ident\" configuration file.\n" "This can be specified as \"ident_file\" in \"%s\", " "or by the -D invocation option, or by the " "PGDATA environment variable.\n", progname, ConfigFileName); return false; } SetConfigOption("ident_file", fname, PGC_POSTMASTER, PGC_S_OVERRIDE); if (fname_is_malloced) free(fname); else guc_free(fname); free(configdir); return true; } /* * pg_timezone_abbrev_initialize --- set default value if not done already * * This is called after initial loading of postgresql.conf. If no * timezone_abbreviations setting was found therein, select default. * If a non-default value is already installed, nothing will happen. * * This can also be called from ProcessConfigFile to establish the default * value after a postgresql.conf entry for it is removed. */ static void pg_timezone_abbrev_initialize(void) { SetConfigOption("timezone_abbreviations", "Default", PGC_POSTMASTER, PGC_S_DYNAMIC_DEFAULT); } /* * Reset all options to their saved default values (implements RESET ALL) */ void ResetAllOptions(void) { dlist_mutable_iter iter; /* We need only consider GUCs not already at PGC_S_DEFAULT */ dlist_foreach_modify(iter, &guc_nondef_list) { struct config_generic *gconf = dlist_container(struct config_generic, nondef_link, iter.cur); /* Don't reset non-SET-able values */ if (gconf->context != PGC_SUSET && gconf->context != PGC_USERSET) continue; /* Don't reset if special exclusion from RESET ALL */ if (gconf->flags & GUC_NO_RESET_ALL) continue; /* No need to reset if wasn't SET */ if (gconf->source <= PGC_S_OVERRIDE) continue; /* Save old value to support transaction abort */ push_old_value(gconf, GUC_ACTION_SET); switch (gconf->vartype) { case PGC_BOOL: { struct config_bool *conf = (struct config_bool *) gconf; if (conf->assign_hook) conf->assign_hook(conf->reset_val, conf->reset_extra); *conf->variable = conf->reset_val; set_extra_field(&conf->gen, &conf->gen.extra, conf->reset_extra); break; } case PGC_INT: { struct config_int *conf = (struct config_int *) gconf; if (conf->assign_hook) conf->assign_hook(conf->reset_val, conf->reset_extra); *conf->variable = conf->reset_val; set_extra_field(&conf->gen, &conf->gen.extra, conf->reset_extra); break; } case PGC_REAL: { struct config_real *conf = (struct config_real *) gconf; if (conf->assign_hook) conf->assign_hook(conf->reset_val, conf->reset_extra); *conf->variable = conf->reset_val; set_extra_field(&conf->gen, &conf->gen.extra, conf->reset_extra); break; } case PGC_STRING: { struct config_string *conf = (struct config_string *) gconf; if (conf->assign_hook) conf->assign_hook(conf->reset_val, conf->reset_extra); set_string_field(conf, conf->variable, conf->reset_val); set_extra_field(&conf->gen, &conf->gen.extra, conf->reset_extra); break; } case PGC_ENUM: { struct config_enum *conf = (struct config_enum *) gconf; if (conf->assign_hook) conf->assign_hook(conf->reset_val, conf->reset_extra); *conf->variable = conf->reset_val; set_extra_field(&conf->gen, &conf->gen.extra, conf->reset_extra); break; } } set_guc_source(gconf, gconf->reset_source); gconf->scontext = gconf->reset_scontext; gconf->srole = gconf->reset_srole; if ((gconf->flags & GUC_REPORT) && !(gconf->status & GUC_NEEDS_REPORT)) { gconf->status |= GUC_NEEDS_REPORT; slist_push_head(&guc_report_list, &gconf->report_link); } } } /* * Apply a change to a GUC variable's "source" field. * * Use this rather than just assigning, to ensure that the variable's * membership in guc_nondef_list is updated correctly. */ static void set_guc_source(struct config_generic *gconf, GucSource newsource) { /* Adjust nondef list membership if appropriate for change */ if (gconf->source == PGC_S_DEFAULT) { if (newsource != PGC_S_DEFAULT) dlist_push_tail(&guc_nondef_list, &gconf->nondef_link); } else { if (newsource == PGC_S_DEFAULT) dlist_delete(&gconf->nondef_link); } /* Now update the source field */ gconf->source = newsource; } /* * push_old_value * Push previous state during transactional assignment to a GUC variable. */ static void push_old_value(struct config_generic *gconf, GucAction action) { GucStack *stack; /* If we're not inside a nest level, do nothing */ if (GUCNestLevel == 0) return; /* Do we already have a stack entry of the current nest level? */ stack = gconf->stack; if (stack && stack->nest_level >= GUCNestLevel) { /* Yes, so adjust its state if necessary */ Assert(stack->nest_level == GUCNestLevel); switch (action) { case GUC_ACTION_SET: /* SET overrides any prior action at same nest level */ if (stack->state == GUC_SET_LOCAL) { /* must discard old masked value */ discard_stack_value(gconf, &stack->masked); } stack->state = GUC_SET; break; case GUC_ACTION_LOCAL: if (stack->state == GUC_SET) { /* SET followed by SET LOCAL, remember SET's value */ stack->masked_scontext = gconf->scontext; stack->masked_srole = gconf->srole; set_stack_value(gconf, &stack->masked); stack->state = GUC_SET_LOCAL; } /* in all other cases, no change to stack entry */ break; case GUC_ACTION_SAVE: /* Could only have a prior SAVE of same variable */ Assert(stack->state == GUC_SAVE); break; } return; } /* * Push a new stack entry * * We keep all the stack entries in TopTransactionContext for simplicity. */ stack = (GucStack *) MemoryContextAllocZero(TopTransactionContext, sizeof(GucStack)); stack->prev = gconf->stack; stack->nest_level = GUCNestLevel; switch (action) { case GUC_ACTION_SET: stack->state = GUC_SET; break; case GUC_ACTION_LOCAL: stack->state = GUC_LOCAL; break; case GUC_ACTION_SAVE: stack->state = GUC_SAVE; break; } stack->source = gconf->source; stack->scontext = gconf->scontext; stack->srole = gconf->srole; set_stack_value(gconf, &stack->prior); if (gconf->stack == NULL) slist_push_head(&guc_stack_list, &gconf->stack_link); gconf->stack = stack; } /* * Do GUC processing at main transaction start. */ void AtStart_GUC(void) { /* * The nest level should be 0 between transactions; if it isn't, somebody * didn't call AtEOXact_GUC, or called it with the wrong nestLevel. We * throw a warning but make no other effort to clean up. */ if (GUCNestLevel != 0) elog(WARNING, "GUC nest level = %d at transaction start", GUCNestLevel); GUCNestLevel = 1; } /* * Enter a new nesting level for GUC values. This is called at subtransaction * start, and when entering a function that has proconfig settings, and in * some other places where we want to set GUC variables transiently. * NOTE we must not risk error here, else subtransaction start will be unhappy. */ int NewGUCNestLevel(void) { return ++GUCNestLevel; } /* * Set search_path to a fixed value for maintenance operations. No effect * during bootstrap, when the search_path is already set to a fixed value and * cannot be changed. */ void RestrictSearchPath(void) { if (!IsBootstrapProcessingMode()) set_config_option("search_path", GUC_SAFE_SEARCH_PATH, PGC_USERSET, PGC_S_SESSION, GUC_ACTION_SAVE, true, 0, false); } /* * Do GUC processing at transaction or subtransaction commit or abort, or * when exiting a function that has proconfig settings, or when undoing a * transient assignment to some GUC variables. (The name is thus a bit of * a misnomer; perhaps it should be ExitGUCNestLevel or some such.) * During abort, we discard all GUC settings that were applied at nesting * levels >= nestLevel. nestLevel == 1 corresponds to the main transaction. */ void AtEOXact_GUC(bool isCommit, int nestLevel) { slist_mutable_iter iter; /* * Note: it's possible to get here with GUCNestLevel == nestLevel-1 during * abort, if there is a failure during transaction start before * AtStart_GUC is called. */ Assert(nestLevel > 0 && (nestLevel <= GUCNestLevel || (nestLevel == GUCNestLevel + 1 && !isCommit))); /* We need only process GUCs having nonempty stacks */ slist_foreach_modify(iter, &guc_stack_list) { struct config_generic *gconf = slist_container(struct config_generic, stack_link, iter.cur); GucStack *stack; /* * Process and pop each stack entry within the nest level. To simplify * fmgr_security_definer() and other places that use GUC_ACTION_SAVE, * we allow failure exit from code that uses a local nest level to be * recovered at the surrounding transaction or subtransaction abort; * so there could be more than one stack entry to pop. */ while ((stack = gconf->stack) != NULL && stack->nest_level >= nestLevel) { GucStack *prev = stack->prev; bool restorePrior = false; bool restoreMasked = false; bool changed; /* * In this next bit, if we don't set either restorePrior or * restoreMasked, we must "discard" any unwanted fields of the * stack entries to avoid leaking memory. If we do set one of * those flags, unused fields will be cleaned up after restoring. */ if (!isCommit) /* if abort, always restore prior value */ restorePrior = true; else if (stack->state == GUC_SAVE) restorePrior = true; else if (stack->nest_level == 1) { /* transaction commit */ if (stack->state == GUC_SET_LOCAL) restoreMasked = true; else if (stack->state == GUC_SET) { /* we keep the current active value */ discard_stack_value(gconf, &stack->prior); } else /* must be GUC_LOCAL */ restorePrior = true; } else if (prev == NULL || prev->nest_level < stack->nest_level - 1) { /* decrement entry's level and do not pop it */ stack->nest_level--; continue; } else { /* * We have to merge this stack entry into prev. See README for * discussion of this bit. */ switch (stack->state) { case GUC_SAVE: Assert(false); /* can't get here */ break; case GUC_SET: /* next level always becomes SET */ discard_stack_value(gconf, &stack->prior); if (prev->state == GUC_SET_LOCAL) discard_stack_value(gconf, &prev->masked); prev->state = GUC_SET; break; case GUC_LOCAL: if (prev->state == GUC_SET) { /* LOCAL migrates down */ prev->masked_scontext = stack->scontext; prev->masked_srole = stack->srole; prev->masked = stack->prior; prev->state = GUC_SET_LOCAL; } else { /* else just forget this stack level */ discard_stack_value(gconf, &stack->prior); } break; case GUC_SET_LOCAL: /* prior state at this level no longer wanted */ discard_stack_value(gconf, &stack->prior); /* copy down the masked state */ prev->masked_scontext = stack->masked_scontext; prev->masked_srole = stack->masked_srole; if (prev->state == GUC_SET_LOCAL) discard_stack_value(gconf, &prev->masked); prev->masked = stack->masked; prev->state = GUC_SET_LOCAL; break; } } changed = false; if (restorePrior || restoreMasked) { /* Perform appropriate restoration of the stacked value */ config_var_value newvalue; GucSource newsource; GucContext newscontext; Oid newsrole; if (restoreMasked) { newvalue = stack->masked; newsource = PGC_S_SESSION; newscontext = stack->masked_scontext; newsrole = stack->masked_srole; } else { newvalue = stack->prior; newsource = stack->source; newscontext = stack->scontext; newsrole = stack->srole; } switch (gconf->vartype) { case PGC_BOOL: { struct config_bool *conf = (struct config_bool *) gconf; bool newval = newvalue.val.boolval; void *newextra = newvalue.extra; if (*conf->variable != newval || conf->gen.extra != newextra) { if (conf->assign_hook) conf->assign_hook(newval, newextra); *conf->variable = newval; set_extra_field(&conf->gen, &conf->gen.extra, newextra); changed = true; } break; } case PGC_INT: { struct config_int *conf = (struct config_int *) gconf; int newval = newvalue.val.intval; void *newextra = newvalue.extra; if (*conf->variable != newval || conf->gen.extra != newextra) { if (conf->assign_hook) conf->assign_hook(newval, newextra); *conf->variable = newval; set_extra_field(&conf->gen, &conf->gen.extra, newextra); changed = true; } break; } case PGC_REAL: { struct config_real *conf = (struct config_real *) gconf; double newval = newvalue.val.realval; void *newextra = newvalue.extra; if (*conf->variable != newval || conf->gen.extra != newextra) { if (conf->assign_hook) conf->assign_hook(newval, newextra); *conf->variable = newval; set_extra_field(&conf->gen, &conf->gen.extra, newextra); changed = true; } break; } case PGC_STRING: { struct config_string *conf = (struct config_string *) gconf; char *newval = newvalue.val.stringval; void *newextra = newvalue.extra; if (*conf->variable != newval || conf->gen.extra != newextra) { if (conf->assign_hook) conf->assign_hook(newval, newextra); set_string_field(conf, conf->variable, newval); set_extra_field(&conf->gen, &conf->gen.extra, newextra); changed = true; } /* * Release stacked values if not used anymore. We * could use discard_stack_value() here, but since * we have type-specific code anyway, might as * well inline it. */ set_string_field(conf, &stack->prior.val.stringval, NULL); set_string_field(conf, &stack->masked.val.stringval, NULL); break; } case PGC_ENUM: { struct config_enum *conf = (struct config_enum *) gconf; int newval = newvalue.val.enumval; void *newextra = newvalue.extra; if (*conf->variable != newval || conf->gen.extra != newextra) { if (conf->assign_hook) conf->assign_hook(newval, newextra); *conf->variable = newval; set_extra_field(&conf->gen, &conf->gen.extra, newextra); changed = true; } break; } } /* * Release stacked extra values if not used anymore. */ set_extra_field(gconf, &(stack->prior.extra), NULL); set_extra_field(gconf, &(stack->masked.extra), NULL); /* And restore source information */ set_guc_source(gconf, newsource); gconf->scontext = newscontext; gconf->srole = newsrole; } /* * Pop the GUC's state stack; if it's now empty, remove the GUC * from guc_stack_list. */ gconf->stack = prev; if (prev == NULL) slist_delete_current(&iter); pfree(stack); /* Report new value if we changed it */ if (changed && (gconf->flags & GUC_REPORT) && !(gconf->status & GUC_NEEDS_REPORT)) { gconf->status |= GUC_NEEDS_REPORT; slist_push_head(&guc_report_list, &gconf->report_link); } } /* end of stack-popping loop */ } /* Update nesting level */ GUCNestLevel = nestLevel - 1; } /* * Start up automatic reporting of changes to variables marked GUC_REPORT. * This is executed at completion of backend startup. */ void BeginReportingGUCOptions(void) { HASH_SEQ_STATUS status; GUCHashEntry *hentry; /* * Don't do anything unless talking to an interactive frontend. */ if (whereToSendOutput != DestRemote) return; reporting_enabled = true; /* * Hack for in_hot_standby: set the GUC value true if appropriate. This * is kind of an ugly place to do it, but there's few better options. * * (This could be out of date by the time we actually send it, in which * case the next ReportChangedGUCOptions call will send a duplicate * report.) */ if (RecoveryInProgress()) SetConfigOption("in_hot_standby", "true", PGC_INTERNAL, PGC_S_OVERRIDE); /* Transmit initial values of interesting variables */ hash_seq_init(&status, guc_hashtab); while ((hentry = (GUCHashEntry *) hash_seq_search(&status)) != NULL) { struct config_generic *conf = hentry->gucvar; if (conf->flags & GUC_REPORT) ReportGUCOption(conf); } } /* * ReportChangedGUCOptions: report recently-changed GUC_REPORT variables * * This is called just before we wait for a new client query. * * By handling things this way, we ensure that a ParameterStatus message * is sent at most once per variable per query, even if the variable * changed multiple times within the query. That's quite possible when * using features such as function SET clauses. Function SET clauses * also tend to cause values to change intraquery but eventually revert * to their prevailing values; ReportGUCOption is responsible for avoiding * redundant reports in such cases. */ void ReportChangedGUCOptions(void) { slist_mutable_iter iter; /* Quick exit if not (yet) enabled */ if (!reporting_enabled) return; /* * Since in_hot_standby isn't actually changed by normal GUC actions, we * need a hack to check whether a new value needs to be reported to the * client. For speed, we rely on the assumption that it can never * transition from false to true. */ if (in_hot_standby_guc && !RecoveryInProgress()) SetConfigOption("in_hot_standby", "false", PGC_INTERNAL, PGC_S_OVERRIDE); /* Transmit new values of interesting variables */ slist_foreach_modify(iter, &guc_report_list) { struct config_generic *conf = slist_container(struct config_generic, report_link, iter.cur); Assert((conf->flags & GUC_REPORT) && (conf->status & GUC_NEEDS_REPORT)); ReportGUCOption(conf); conf->status &= ~GUC_NEEDS_REPORT; slist_delete_current(&iter); } } /* * ReportGUCOption: if appropriate, transmit option value to frontend * * We need not transmit the value if it's the same as what we last * transmitted. */ static void ReportGUCOption(struct config_generic *record) { char *val = ShowGUCOption(record, false); if (record->last_reported == NULL || strcmp(val, record->last_reported) != 0) { StringInfoData msgbuf; pq_beginmessage(&msgbuf, PqMsg_ParameterStatus); pq_sendstring(&msgbuf, record->name); pq_sendstring(&msgbuf, val); pq_endmessage(&msgbuf); /* * We need a long-lifespan copy. If guc_strdup() fails due to OOM, * we'll set last_reported to NULL and thereby possibly make a * duplicate report later. */ guc_free(record->last_reported); record->last_reported = guc_strdup(LOG, val); } pfree(val); } /* * Convert a value from one of the human-friendly units ("kB", "min" etc.) * to the given base unit. 'value' and 'unit' are the input value and unit * to convert from (there can be trailing spaces in the unit string). * The converted value is stored in *base_value. * It's caller's responsibility to round off the converted value as necessary * and check for out-of-range. * * Returns true on success, false if the input unit is not recognized. */ static bool convert_to_base_unit(double value, const char *unit, int base_unit, double *base_value) { char unitstr[MAX_UNIT_LEN + 1]; int unitlen; const unit_conversion *table; int i; /* extract unit string to compare to table entries */ unitlen = 0; while (*unit != '\0' && !isspace((unsigned char) *unit) && unitlen < MAX_UNIT_LEN) unitstr[unitlen++] = *(unit++); unitstr[unitlen] = '\0'; /* allow whitespace after unit */ while (isspace((unsigned char) *unit)) unit++; if (*unit != '\0') return false; /* unit too long, or garbage after it */ /* now search the appropriate table */ if (base_unit & GUC_UNIT_MEMORY) table = memory_unit_conversion_table; else table = time_unit_conversion_table; for (i = 0; *table[i].unit; i++) { if (base_unit == table[i].base_unit && strcmp(unitstr, table[i].unit) == 0) { double cvalue = value * table[i].multiplier; /* * If the user gave a fractional value such as "30.1GB", round it * off to the nearest multiple of the next smaller unit, if there * is one. */ if (*table[i + 1].unit && base_unit == table[i + 1].base_unit) cvalue = rint(cvalue / table[i + 1].multiplier) * table[i + 1].multiplier; *base_value = cvalue; return true; } } return false; } /* * Convert an integer value in some base unit to a human-friendly unit. * * The output unit is chosen so that it's the greatest unit that can represent * the value without loss. For example, if the base unit is GUC_UNIT_KB, 1024 * is converted to 1 MB, but 1025 is represented as 1025 kB. */ static void convert_int_from_base_unit(int64 base_value, int base_unit, int64 *value, const char **unit) { const unit_conversion *table; int i; *unit = NULL; if (base_unit & GUC_UNIT_MEMORY) table = memory_unit_conversion_table; else table = time_unit_conversion_table; for (i = 0; *table[i].unit; i++) { if (base_unit == table[i].base_unit) { /* * Accept the first conversion that divides the value evenly. We * assume that the conversions for each base unit are ordered from * greatest unit to the smallest! */ if (table[i].multiplier <= 1.0 || base_value % (int64) table[i].multiplier == 0) { *value = (int64) rint(base_value / table[i].multiplier); *unit = table[i].unit; break; } } } Assert(*unit != NULL); } /* * Convert a floating-point value in some base unit to a human-friendly unit. * * Same as above, except we have to do the math a bit differently, and * there's a possibility that we don't find any exact divisor. */ static void convert_real_from_base_unit(double base_value, int base_unit, double *value, const char **unit) { const unit_conversion *table; int i; *unit = NULL; if (base_unit & GUC_UNIT_MEMORY) table = memory_unit_conversion_table; else table = time_unit_conversion_table; for (i = 0; *table[i].unit; i++) { if (base_unit == table[i].base_unit) { /* * Accept the first conversion that divides the value evenly; or * if there is none, use the smallest (last) target unit. * * What we actually care about here is whether snprintf with "%g" * will print the value as an integer, so the obvious test of * "*value == rint(*value)" is too strict; roundoff error might * make us choose an unreasonably small unit. As a compromise, * accept a divisor that is within 1e-8 of producing an integer. */ *value = base_value / table[i].multiplier; *unit = table[i].unit; if (*value > 0 && fabs((rint(*value) / *value) - 1.0) <= 1e-8) break; } } Assert(*unit != NULL); } /* * Return the name of a GUC's base unit (e.g. "ms") given its flags. * Return NULL if the GUC is unitless. */ const char * get_config_unit_name(int flags) { switch (flags & GUC_UNIT) { case 0: return NULL; /* GUC has no units */ case GUC_UNIT_BYTE: return "B"; case GUC_UNIT_KB: return "kB"; case GUC_UNIT_MB: return "MB"; case GUC_UNIT_BLOCKS: { static char bbuf[8]; /* initialize if first time through */ if (bbuf[0] == '\0') snprintf(bbuf, sizeof(bbuf), "%dkB", BLCKSZ / 1024); return bbuf; } case GUC_UNIT_XBLOCKS: { static char xbuf[8]; /* initialize if first time through */ if (xbuf[0] == '\0') snprintf(xbuf, sizeof(xbuf), "%dkB", XLOG_BLCKSZ / 1024); return xbuf; } case GUC_UNIT_MS: return "ms"; case GUC_UNIT_S: return "s"; case GUC_UNIT_MIN: return "min"; default: elog(ERROR, "unrecognized GUC units value: %d", flags & GUC_UNIT); return NULL; } } /* * Try to parse value as an integer. The accepted formats are the * usual decimal, octal, or hexadecimal formats, as well as floating-point * formats (which will be rounded to integer after any units conversion). * Optionally, the value can be followed by a unit name if "flags" indicates * a unit is allowed. * * If the string parses okay, return true, else false. * If okay and result is not NULL, return the value in *result. * If not okay and hintmsg is not NULL, *hintmsg is set to a suitable * HINT message, or NULL if no hint provided. */ bool parse_int(const char *value, int *result, int flags, const char **hintmsg) { /* * We assume here that double is wide enough to represent any integer * value with adequate precision. */ double val; char *endptr; /* To suppress compiler warnings, always set output params */ if (result) *result = 0; if (hintmsg) *hintmsg = NULL; /* * Try to parse as an integer (allowing octal or hex input). If the * conversion stops at a decimal point or 'e', or overflows, re-parse as * float. This should work fine as long as we have no unit names starting * with 'e'. If we ever do, the test could be extended to check for a * sign or digit after 'e', but for now that's unnecessary. */ errno = 0; val = strtol(value, &endptr, 0); if (*endptr == '.' || *endptr == 'e' || *endptr == 'E' || errno == ERANGE) { errno = 0; val = strtod(value, &endptr); } if (endptr == value || errno == ERANGE) return false; /* no HINT for these cases */ /* reject NaN (infinities will fail range check below) */ if (isnan(val)) return false; /* treat same as syntax error; no HINT */ /* allow whitespace between number and unit */ while (isspace((unsigned char) *endptr)) endptr++; /* Handle possible unit */ if (*endptr != '\0') { if ((flags & GUC_UNIT) == 0) return false; /* this setting does not accept a unit */ if (!convert_to_base_unit(val, endptr, (flags & GUC_UNIT), &val)) { /* invalid unit, or garbage after the unit; set hint and fail. */ if (hintmsg) { if (flags & GUC_UNIT_MEMORY) *hintmsg = memory_units_hint; else *hintmsg = time_units_hint; } return false; } } /* Round to int, then check for overflow */ val = rint(val); if (val > INT_MAX || val < INT_MIN) { if (hintmsg) *hintmsg = gettext_noop("Value exceeds integer range."); return false; } if (result) *result = (int) val; return true; } /* * Try to parse value as a floating point number in the usual format. * Optionally, the value can be followed by a unit name if "flags" indicates * a unit is allowed. * * If the string parses okay, return true, else false. * If okay and result is not NULL, return the value in *result. * If not okay and hintmsg is not NULL, *hintmsg is set to a suitable * HINT message, or NULL if no hint provided. */ bool parse_real(const char *value, double *result, int flags, const char **hintmsg) { double val; char *endptr; /* To suppress compiler warnings, always set output params */ if (result) *result = 0; if (hintmsg) *hintmsg = NULL; errno = 0; val = strtod(value, &endptr); if (endptr == value || errno == ERANGE) return false; /* no HINT for these cases */ /* reject NaN (infinities will fail range checks later) */ if (isnan(val)) return false; /* treat same as syntax error; no HINT */ /* allow whitespace between number and unit */ while (isspace((unsigned char) *endptr)) endptr++; /* Handle possible unit */ if (*endptr != '\0') { if ((flags & GUC_UNIT) == 0) return false; /* this setting does not accept a unit */ if (!convert_to_base_unit(val, endptr, (flags & GUC_UNIT), &val)) { /* invalid unit, or garbage after the unit; set hint and fail. */ if (hintmsg) { if (flags & GUC_UNIT_MEMORY) *hintmsg = memory_units_hint; else *hintmsg = time_units_hint; } return false; } } if (result) *result = val; return true; } /* * Lookup the name for an enum option with the selected value. * Should only ever be called with known-valid values, so throws * an elog(ERROR) if the enum option is not found. * * The returned string is a pointer to static data and not * allocated for modification. */ const char * config_enum_lookup_by_value(struct config_enum *record, int val) { const struct config_enum_entry *entry; for (entry = record->options; entry && entry->name; entry++) { if (entry->val == val) return entry->name; } elog(ERROR, "could not find enum option %d for %s", val, record->gen.name); return NULL; /* silence compiler */ } /* * Lookup the value for an enum option with the selected name * (case-insensitive). * If the enum option is found, sets the retval value and returns * 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, int *retval) { const struct config_enum_entry *entry; for (entry = record->options; entry && entry->name; entry++) { if (pg_strcasecmp(value, entry->name) == 0) { *retval = entry->val; return true; } } *retval = 0; return false; } /* * Return a palloc'd string listing all the available options for an enum GUC * (excluding hidden ones), separated by the given separator. * If prefix is non-NULL, it is added before the first enum value. * If suffix is non-NULL, it is added to the end of the string. */ char * 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; int seplen; initStringInfo(&retstr); appendStringInfoString(&retstr, prefix); seplen = strlen(separator); for (entry = record->options; entry && entry->name; entry++) { if (!entry->hidden) { appendStringInfoString(&retstr, entry->name); appendBinaryStringInfo(&retstr, separator, seplen); } } /* * 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) { /* Replace final separator */ retstr.data[retstr.len - seplen] = '\0'; retstr.len -= seplen; } appendStringInfoString(&retstr, suffix); return retstr.data; } /* * Parse and validate a proposed value for the specified configuration * parameter. * * This does built-in checks (such as range limits for an integer parameter) * and also calls any check hook the parameter may have. * * record: GUC variable's info record * value: proposed value, as a string * source: identifies source of value (check hooks may need this) * elevel: level to log any error reports at * newval: on success, converted parameter value is returned here * newextra: on success, receives any "extra" data returned by check hook * (caller must initialize *newextra to NULL) * * Returns true if OK, false if not (or throws error, if elevel >= ERROR) */ static bool parse_and_validate_value(struct config_generic *record, const char *value, GucSource source, int elevel, union config_var_val *newval, void **newextra) { switch (record->vartype) { case PGC_BOOL: { struct config_bool *conf = (struct config_bool *) record; if (!parse_bool(value, &newval->boolval)) { ereport(elevel, (errcode(ERRCODE_INVALID_PARAMETER_VALUE), errmsg("parameter \"%s\" requires a Boolean value", conf->gen.name))); return false; } if (!call_bool_check_hook(conf, &newval->boolval, newextra, source, elevel)) return false; } break; case PGC_INT: { struct config_int *conf = (struct config_int *) record; const char *hintmsg; if (!parse_int(value, &newval->intval, conf->gen.flags, &hintmsg)) { ereport(elevel, (errcode(ERRCODE_INVALID_PARAMETER_VALUE), errmsg("invalid value for parameter \"%s\": \"%s\"", conf->gen.name, value), hintmsg ? errhint("%s", _(hintmsg)) : 0)); return false; } if (newval->intval < conf->min || newval->intval > conf->max) { const char *unit = get_config_unit_name(conf->gen.flags); const char *unitspace; if (unit) unitspace = " "; else unit = unitspace = ""; ereport(elevel, (errcode(ERRCODE_INVALID_PARAMETER_VALUE), errmsg("%d%s%s is outside the valid range for parameter \"%s\" (%d%s%s .. %d%s%s)", newval->intval, unitspace, unit, conf->gen.name, conf->min, unitspace, unit, conf->max, unitspace, unit))); return false; } if (!call_int_check_hook(conf, &newval->intval, newextra, source, elevel)) return false; } break; case PGC_REAL: { struct config_real *conf = (struct config_real *) record; const char *hintmsg; if (!parse_real(value, &newval->realval, conf->gen.flags, &hintmsg)) { ereport(elevel, (errcode(ERRCODE_INVALID_PARAMETER_VALUE), errmsg("invalid value for parameter \"%s\": \"%s\"", conf->gen.name, value), hintmsg ? errhint("%s", _(hintmsg)) : 0)); return false; } if (newval->realval < conf->min || newval->realval > conf->max) { const char *unit = get_config_unit_name(conf->gen.flags); const char *unitspace; if (unit) unitspace = " "; else unit = unitspace = ""; ereport(elevel, (errcode(ERRCODE_INVALID_PARAMETER_VALUE), errmsg("%g%s%s is outside the valid range for parameter \"%s\" (%g%s%s .. %g%s%s)", newval->realval, unitspace, unit, conf->gen.name, conf->min, unitspace, unit, conf->max, unitspace, unit))); return false; } if (!call_real_check_hook(conf, &newval->realval, newextra, source, elevel)) return false; } break; case PGC_STRING: { struct config_string *conf = (struct config_string *) record; /* * The value passed by the caller could be transient, so we * always strdup it. */ newval->stringval = guc_strdup(elevel, value); if (newval->stringval == NULL) return false; /* * The only built-in "parsing" check we have is to apply * truncation if GUC_IS_NAME. */ if (conf->gen.flags & GUC_IS_NAME) truncate_identifier(newval->stringval, strlen(newval->stringval), true); if (!call_string_check_hook(conf, &newval->stringval, newextra, source, elevel)) { guc_free(newval->stringval); newval->stringval = NULL; return false; } } break; case PGC_ENUM: { struct config_enum *conf = (struct config_enum *) record; if (!config_enum_lookup_by_name(conf, value, &newval->enumval)) { char *hintmsg; hintmsg = config_enum_get_options(conf, "Available values: ", ".", ", "); ereport(elevel, (errcode(ERRCODE_INVALID_PARAMETER_VALUE), errmsg("invalid value for parameter \"%s\": \"%s\"", conf->gen.name, value), hintmsg ? errhint("%s", _(hintmsg)) : 0)); if (hintmsg) pfree(hintmsg); return false; } if (!call_enum_check_hook(conf, &newval->enumval, newextra, source, elevel)) return false; } break; } return true; } /* * set_config_option: sets option `name' to given value. * * The value should be a string, which will be parsed and converted to * the appropriate data type. The context and source parameters indicate * in which context this function is being called, so that it can apply the * access restrictions properly. * * If value is NULL, set the option to its default value (normally the * reset_val, but if source == PGC_S_DEFAULT we instead use the boot_val). * * action indicates whether to set the value globally in the session, locally * to the current top transaction, or just for the duration of a function call. * * If changeVal is false then don't really set the option but do all * the checks to see if it would work. * * elevel should normally be passed as zero, allowing this function to make * its standard choice of ereport level. However some callers need to be * able to override that choice; they should pass the ereport level to use. * * is_reload should be true only when called from read_nondefault_variables() * or RestoreGUCState(), where we are trying to load some other process's * GUC settings into a new process. * * Return value: * +1: the value is valid and was successfully applied. * 0: the name or value is invalid, or it's invalid to try to set * this GUC now; but elevel was less than ERROR (see below). * -1: no error detected, but the value was not applied, either * because changeVal is false or there is some overriding setting. * * If there is an error (non-existing option, invalid value, etc) then an * ereport(ERROR) is thrown *unless* this is called for a source for which * we don't want an ERROR (currently, those are defaults, the config file, * and per-database or per-user settings, as well as callers who specify * a less-than-ERROR elevel). In those cases we write a suitable error * message via ereport() and return 0. * * See also SetConfigOption for an external interface. */ int set_config_option(const char *name, const char *value, GucContext context, GucSource source, GucAction action, bool changeVal, int elevel, bool is_reload) { Oid srole; /* * Non-interactive sources should be treated as having all privileges, * except for PGC_S_CLIENT. Note in particular that this is true for * pg_db_role_setting sources (PGC_S_GLOBAL etc): we assume a suitable * privilege check was done when the pg_db_role_setting entry was made. */ if (source >= PGC_S_INTERACTIVE || source == PGC_S_CLIENT) srole = GetUserId(); else srole = BOOTSTRAP_SUPERUSERID; return set_config_with_handle(name, NULL, value, context, source, srole, action, changeVal, elevel, is_reload); } /* * set_config_option_ext: sets option `name' to given value. * * This API adds the ability to explicitly specify which role OID * is considered to be setting the value. Most external callers can use * set_config_option() and let it determine that based on the GucSource, * but there are a few that are supplying a value that was determined * in some special way and need to override the decision. Also, when * restoring a previously-assigned value, it's important to supply the * same role OID that set the value originally; so all guc.c callers * that are doing that type of thing need to call this directly. * * Generally, srole should be GetUserId() when the source is a SQL operation, * or BOOTSTRAP_SUPERUSERID if the source is a config file or similar. */ int set_config_option_ext(const char *name, const char *value, GucContext context, GucSource source, Oid srole, GucAction action, bool changeVal, int elevel, bool is_reload) { return set_config_with_handle(name, NULL, value, context, source, srole, action, changeVal, elevel, is_reload); } /* * set_config_with_handle: sets option `name' to given value. * * This API adds the ability to pass a 'handle' argument, which can be * obtained by the caller from get_config_handle(). NULL has no effect, * but a non-null value avoids the need to search the GUC tables. * * This should be used by callers which repeatedly set the same config * option(s), and want to avoid the overhead of a hash lookup each time. */ int set_config_with_handle(const char *name, config_handle *handle, const char *value, GucContext context, GucSource source, Oid srole, GucAction action, bool changeVal, int elevel, bool is_reload) { struct config_generic *record; union config_var_val newval_union; void *newextra = NULL; bool prohibitValueChange = false; bool makeDefault; if (elevel == 0) { if (source == PGC_S_DEFAULT || source == PGC_S_FILE) { /* * To avoid cluttering the log, only the postmaster bleats loudly * about problems with the config file. */ elevel = IsUnderPostmaster ? DEBUG3 : LOG; } else if (source == PGC_S_GLOBAL || source == PGC_S_DATABASE || source == PGC_S_USER || source == PGC_S_DATABASE_USER) elevel = WARNING; else elevel = ERROR; } /* if handle is specified, no need to look up option */ if (!handle) { record = find_option(name, true, false, elevel); if (record == NULL) return 0; } else record = handle; /* * GUC_ACTION_SAVE changes are acceptable during a parallel operation, * because the current worker will also pop the change. We're probably * dealing with a function having a proconfig entry. Only the function's * body should observe the change, and peer workers do not share in the * execution of a function call started by this worker. * * Also allow normal setting if the GUC is marked GUC_ALLOW_IN_PARALLEL. * * Other changes might need to affect other workers, so forbid them. */ if (IsInParallelMode() && changeVal && action != GUC_ACTION_SAVE && (record->flags & GUC_ALLOW_IN_PARALLEL) == 0) { ereport(elevel, (errcode(ERRCODE_INVALID_TRANSACTION_STATE), errmsg("parameter \"%s\" cannot be set during a parallel operation", record->name))); return 0; } /* * Check if the option can be set at this time. See guc.h for the precise * rules. */ switch (record->context) { case PGC_INTERNAL: if (context != PGC_INTERNAL) { ereport(elevel, (errcode(ERRCODE_CANT_CHANGE_RUNTIME_PARAM), errmsg("parameter \"%s\" cannot be changed", record->name))); return 0; } break; case PGC_POSTMASTER: if (context == PGC_SIGHUP) { /* * We are re-reading a PGC_POSTMASTER variable from * postgresql.conf. We can't change the setting, so we should * give a warning if the DBA tries to change it. However, * because of variant formats, canonicalization by check * hooks, etc, we can't just compare the given string directly * to what's stored. Set a flag to check below after we have * the final storable value. */ prohibitValueChange = true; } else if (context != PGC_POSTMASTER) { ereport(elevel, (errcode(ERRCODE_CANT_CHANGE_RUNTIME_PARAM), errmsg("parameter \"%s\" cannot be changed without restarting the server", record->name))); return 0; } break; case PGC_SIGHUP: if (context != PGC_SIGHUP && context != PGC_POSTMASTER) { ereport(elevel, (errcode(ERRCODE_CANT_CHANGE_RUNTIME_PARAM), errmsg("parameter \"%s\" cannot be changed now", record->name))); return 0; } /* * Hmm, the idea of the SIGHUP context is "ought to be global, but * can be changed after postmaster start". But there's nothing * that prevents a crafty administrator from sending SIGHUP * signals to individual backends only. */ break; case PGC_SU_BACKEND: if (context == PGC_BACKEND) { /* * Check whether the requesting user has been granted * privilege to set this GUC. */ AclResult aclresult; aclresult = pg_parameter_aclcheck(record->name, srole, ACL_SET); if (aclresult != ACLCHECK_OK) { /* No granted privilege */ ereport(elevel, (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE), errmsg("permission denied to set parameter \"%s\"", record->name))); return 0; } } /* fall through to process the same as PGC_BACKEND */ /* FALLTHROUGH */ case PGC_BACKEND: if (context == PGC_SIGHUP) { /* * If a PGC_BACKEND or PGC_SU_BACKEND parameter is changed in * the config file, we want to accept the new value in the * postmaster (whence it will propagate to * subsequently-started backends), but ignore it in existing * backends. This is a tad klugy, but necessary because we * don't re-read the config file during backend start. * * However, if changeVal is false then plow ahead anyway since * we are trying to find out if the value is potentially good, * not actually use it. * * In EXEC_BACKEND builds, this works differently: we load all * non-default settings from the CONFIG_EXEC_PARAMS file * during backend start. In that case we must accept * PGC_SIGHUP settings, so as to have the same value as if * we'd forked from the postmaster. This can also happen when * using RestoreGUCState() within a background worker that * needs to have the same settings as the user backend that * started it. is_reload will be true when either situation * applies. */ if (IsUnderPostmaster && changeVal && !is_reload) return -1; } else if (context != PGC_POSTMASTER && context != PGC_BACKEND && context != PGC_SU_BACKEND && source != PGC_S_CLIENT) { ereport(elevel, (errcode(ERRCODE_CANT_CHANGE_RUNTIME_PARAM), errmsg("parameter \"%s\" cannot be set after connection start", record->name))); return 0; } break; case PGC_SUSET: if (context == PGC_USERSET || context == PGC_BACKEND) { /* * Check whether the requesting user has been granted * privilege to set this GUC. */ AclResult aclresult; aclresult = pg_parameter_aclcheck(record->name, srole, ACL_SET); if (aclresult != ACLCHECK_OK) { /* No granted privilege */ ereport(elevel, (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE), errmsg("permission denied to set parameter \"%s\"", record->name))); return 0; } } break; case PGC_USERSET: /* always okay */ 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", record->name))); return 0; } if (InSecurityRestrictedOperation()) { ereport(elevel, (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE), errmsg("cannot set parameter \"%s\" within security-restricted operation", record->name))); return 0; } } /* Disallow resetting and saving GUC_NO_RESET values */ if (record->flags & GUC_NO_RESET) { if (value == NULL) { ereport(elevel, (errcode(ERRCODE_FEATURE_NOT_SUPPORTED), errmsg("parameter \"%s\" cannot be reset", record->name))); return 0; } if (action == GUC_ACTION_SAVE) { ereport(elevel, (errcode(ERRCODE_FEATURE_NOT_SUPPORTED), errmsg("parameter \"%s\" cannot be set locally in functions", record->name))); return 0; } } /* * Should we set reset/stacked values? (If so, the behavior is not * transactional.) This is done either when we get a default value from * the database's/user's/client's default settings or when we reset a * value to its default. */ makeDefault = changeVal && (source <= PGC_S_OVERRIDE) && ((value != NULL) || source == PGC_S_DEFAULT); /* * Ignore attempted set if overridden by previously processed setting. * However, if changeVal is false then plow ahead anyway since we are * trying to find out if the value is potentially good, not actually use * it. Also keep going if makeDefault is true, since we may want to set * the reset/stacked values even if we can't set the variable itself. */ if (record->source > source) { if (changeVal && !makeDefault) { elog(DEBUG3, "\"%s\": setting ignored because previous source is higher priority", record->name); return -1; } changeVal = false; } /* * Evaluate value and set variable. */ switch (record->vartype) { case PGC_BOOL: { struct config_bool *conf = (struct config_bool *) record; #define newval (newval_union.boolval) if (value) { if (!parse_and_validate_value(record, value, source, elevel, &newval_union, &newextra)) return 0; } else if (source == PGC_S_DEFAULT) { newval = conf->boot_val; if (!call_bool_check_hook(conf, &newval, &newextra, source, elevel)) return 0; } else { newval = conf->reset_val; newextra = conf->reset_extra; source = conf->gen.reset_source; context = conf->gen.reset_scontext; srole = conf->gen.reset_srole; } if (prohibitValueChange) { /* Release newextra, unless it's reset_extra */ if (newextra && !extra_field_used(&conf->gen, newextra)) guc_free(newextra); if (*conf->variable != newval) { record->status |= GUC_PENDING_RESTART; ereport(elevel, (errcode(ERRCODE_CANT_CHANGE_RUNTIME_PARAM), errmsg("parameter \"%s\" cannot be changed without restarting the server", conf->gen.name))); return 0; } record->status &= ~GUC_PENDING_RESTART; return -1; } if (changeVal) { /* Save old value to support transaction abort */ if (!makeDefault) push_old_value(&conf->gen, action); if (conf->assign_hook) conf->assign_hook(newval, newextra); *conf->variable = newval; set_extra_field(&conf->gen, &conf->gen.extra, newextra); set_guc_source(&conf->gen, source); conf->gen.scontext = context; conf->gen.srole = srole; } if (makeDefault) { GucStack *stack; if (conf->gen.reset_source <= source) { conf->reset_val = newval; set_extra_field(&conf->gen, &conf->reset_extra, newextra); conf->gen.reset_source = source; conf->gen.reset_scontext = context; conf->gen.reset_srole = srole; } for (stack = conf->gen.stack; stack; stack = stack->prev) { if (stack->source <= source) { stack->prior.val.boolval = newval; set_extra_field(&conf->gen, &stack->prior.extra, newextra); stack->source = source; stack->scontext = context; stack->srole = srole; } } } /* Perhaps we didn't install newextra anywhere */ if (newextra && !extra_field_used(&conf->gen, newextra)) guc_free(newextra); break; #undef newval } case PGC_INT: { struct config_int *conf = (struct config_int *) record; #define newval (newval_union.intval) if (value) { if (!parse_and_validate_value(record, value, source, elevel, &newval_union, &newextra)) return 0; } else if (source == PGC_S_DEFAULT) { newval = conf->boot_val; if (!call_int_check_hook(conf, &newval, &newextra, source, elevel)) return 0; } else { newval = conf->reset_val; newextra = conf->reset_extra; source = conf->gen.reset_source; context = conf->gen.reset_scontext; srole = conf->gen.reset_srole; } if (prohibitValueChange) { /* Release newextra, unless it's reset_extra */ if (newextra && !extra_field_used(&conf->gen, newextra)) guc_free(newextra); if (*conf->variable != newval) { record->status |= GUC_PENDING_RESTART; ereport(elevel, (errcode(ERRCODE_CANT_CHANGE_RUNTIME_PARAM), errmsg("parameter \"%s\" cannot be changed without restarting the server", conf->gen.name))); return 0; } record->status &= ~GUC_PENDING_RESTART; return -1; } if (changeVal) { /* Save old value to support transaction abort */ if (!makeDefault) push_old_value(&conf->gen, action); if (conf->assign_hook) conf->assign_hook(newval, newextra); *conf->variable = newval; set_extra_field(&conf->gen, &conf->gen.extra, newextra); set_guc_source(&conf->gen, source); conf->gen.scontext = context; conf->gen.srole = srole; } if (makeDefault) { GucStack *stack; if (conf->gen.reset_source <= source) { conf->reset_val = newval; set_extra_field(&conf->gen, &conf->reset_extra, newextra); conf->gen.reset_source = source; conf->gen.reset_scontext = context; conf->gen.reset_srole = srole; } for (stack = conf->gen.stack; stack; stack = stack->prev) { if (stack->source <= source) { stack->prior.val.intval = newval; set_extra_field(&conf->gen, &stack->prior.extra, newextra); stack->source = source; stack->scontext = context; stack->srole = srole; } } } /* Perhaps we didn't install newextra anywhere */ if (newextra && !extra_field_used(&conf->gen, newextra)) guc_free(newextra); break; #undef newval } case PGC_REAL: { struct config_real *conf = (struct config_real *) record; #define newval (newval_union.realval) if (value) { if (!parse_and_validate_value(record, value, source, elevel, &newval_union, &newextra)) return 0; } else if (source == PGC_S_DEFAULT) { newval = conf->boot_val; if (!call_real_check_hook(conf, &newval, &newextra, source, elevel)) return 0; } else { newval = conf->reset_val; newextra = conf->reset_extra; source = conf->gen.reset_source; context = conf->gen.reset_scontext; srole = conf->gen.reset_srole; } if (prohibitValueChange) { /* Release newextra, unless it's reset_extra */ if (newextra && !extra_field_used(&conf->gen, newextra)) guc_free(newextra); if (*conf->variable != newval) { record->status |= GUC_PENDING_RESTART; ereport(elevel, (errcode(ERRCODE_CANT_CHANGE_RUNTIME_PARAM), errmsg("parameter \"%s\" cannot be changed without restarting the server", conf->gen.name))); return 0; } record->status &= ~GUC_PENDING_RESTART; return -1; } if (changeVal) { /* Save old value to support transaction abort */ if (!makeDefault) push_old_value(&conf->gen, action); if (conf->assign_hook) conf->assign_hook(newval, newextra); *conf->variable = newval; set_extra_field(&conf->gen, &conf->gen.extra, newextra); set_guc_source(&conf->gen, source); conf->gen.scontext = context; conf->gen.srole = srole; } if (makeDefault) { GucStack *stack; if (conf->gen.reset_source <= source) { conf->reset_val = newval; set_extra_field(&conf->gen, &conf->reset_extra, newextra); conf->gen.reset_source = source; conf->gen.reset_scontext = context; conf->gen.reset_srole = srole; } for (stack = conf->gen.stack; stack; stack = stack->prev) { if (stack->source <= source) { stack->prior.val.realval = newval; set_extra_field(&conf->gen, &stack->prior.extra, newextra); stack->source = source; stack->scontext = context; stack->srole = srole; } } } /* Perhaps we didn't install newextra anywhere */ if (newextra && !extra_field_used(&conf->gen, newextra)) guc_free(newextra); break; #undef newval } case PGC_STRING: { struct config_string *conf = (struct config_string *) record; GucContext orig_context = context; GucSource orig_source = source; Oid orig_srole = srole; #define newval (newval_union.stringval) if (value) { if (!parse_and_validate_value(record, value, source, elevel, &newval_union, &newextra)) return 0; } else if (source == PGC_S_DEFAULT) { /* non-NULL boot_val must always get strdup'd */ if (conf->boot_val != NULL) { newval = guc_strdup(elevel, conf->boot_val); if (newval == NULL) return 0; } else newval = NULL; if (!call_string_check_hook(conf, &newval, &newextra, source, elevel)) { guc_free(newval); return 0; } } else { /* * strdup not needed, since reset_val is already under * guc.c's control */ newval = conf->reset_val; newextra = conf->reset_extra; source = conf->gen.reset_source; context = conf->gen.reset_scontext; srole = conf->gen.reset_srole; } if (prohibitValueChange) { bool newval_different; /* newval shouldn't be NULL, so we're a bit sloppy here */ newval_different = (*conf->variable == NULL || newval == NULL || strcmp(*conf->variable, newval) != 0); /* Release newval, unless it's reset_val */ if (newval && !string_field_used(conf, newval)) guc_free(newval); /* Release newextra, unless it's reset_extra */ if (newextra && !extra_field_used(&conf->gen, newextra)) guc_free(newextra); if (newval_different) { record->status |= GUC_PENDING_RESTART; ereport(elevel, (errcode(ERRCODE_CANT_CHANGE_RUNTIME_PARAM), errmsg("parameter \"%s\" cannot be changed without restarting the server", conf->gen.name))); return 0; } record->status &= ~GUC_PENDING_RESTART; return -1; } if (changeVal) { /* Save old value to support transaction abort */ if (!makeDefault) push_old_value(&conf->gen, action); if (conf->assign_hook) conf->assign_hook(newval, newextra); set_string_field(conf, conf->variable, newval); set_extra_field(&conf->gen, &conf->gen.extra, newextra); set_guc_source(&conf->gen, source); conf->gen.scontext = context; conf->gen.srole = srole; /* * Ugly hack: during SET session_authorization, forcibly * do SET ROLE NONE with the same context/source/etc, so * that the effects will have identical lifespan. This is * required by the SQL spec, and it's not possible to do * it within the variable's check hook or assign hook * because our APIs for those don't pass enough info. * However, don't do it if is_reload: in that case we * expect that if "role" isn't supposed to be default, it * has been or will be set by a separate reload action. * * Also, for the call from InitializeSessionUserId with * source == PGC_S_OVERRIDE, use PGC_S_DYNAMIC_DEFAULT for * "role"'s source, so that it's still possible to set * "role" from pg_db_role_setting entries. (See notes in * InitializeSessionUserId before changing this.) * * A fine point: for RESET session_authorization, we do * "RESET role" not "SET ROLE NONE" (by passing down NULL * rather than "none" for the value). This would have the * same effects in typical cases, but if the reset value * of "role" is not "none" it seems better to revert to * that. */ if (!is_reload && strcmp(conf->gen.name, "session_authorization") == 0) (void) set_config_with_handle("role", NULL, value ? "none" : NULL, orig_context, (orig_source == PGC_S_OVERRIDE) ? PGC_S_DYNAMIC_DEFAULT : orig_source, orig_srole, action, true, elevel, false); } if (makeDefault) { GucStack *stack; if (conf->gen.reset_source <= source) { set_string_field(conf, &conf->reset_val, newval); set_extra_field(&conf->gen, &conf->reset_extra, newextra); conf->gen.reset_source = source; conf->gen.reset_scontext = context; conf->gen.reset_srole = srole; } for (stack = conf->gen.stack; stack; stack = stack->prev) { if (stack->source <= source) { set_string_field(conf, &stack->prior.val.stringval, newval); set_extra_field(&conf->gen, &stack->prior.extra, newextra); stack->source = source; stack->scontext = context; stack->srole = srole; } } } /* Perhaps we didn't install newval anywhere */ if (newval && !string_field_used(conf, newval)) guc_free(newval); /* Perhaps we didn't install newextra anywhere */ if (newextra && !extra_field_used(&conf->gen, newextra)) guc_free(newextra); break; #undef newval } case PGC_ENUM: { struct config_enum *conf = (struct config_enum *) record; #define newval (newval_union.enumval) if (value) { if (!parse_and_validate_value(record, value, source, elevel, &newval_union, &newextra)) return 0; } else if (source == PGC_S_DEFAULT) { newval = conf->boot_val; if (!call_enum_check_hook(conf, &newval, &newextra, source, elevel)) return 0; } else { newval = conf->reset_val; newextra = conf->reset_extra; source = conf->gen.reset_source; context = conf->gen.reset_scontext; srole = conf->gen.reset_srole; } if (prohibitValueChange) { /* Release newextra, unless it's reset_extra */ if (newextra && !extra_field_used(&conf->gen, newextra)) guc_free(newextra); if (*conf->variable != newval) { record->status |= GUC_PENDING_RESTART; ereport(elevel, (errcode(ERRCODE_CANT_CHANGE_RUNTIME_PARAM), errmsg("parameter \"%s\" cannot be changed without restarting the server", conf->gen.name))); return 0; } record->status &= ~GUC_PENDING_RESTART; return -1; } if (changeVal) { /* Save old value to support transaction abort */ if (!makeDefault) push_old_value(&conf->gen, action); if (conf->assign_hook) conf->assign_hook(newval, newextra); *conf->variable = newval; set_extra_field(&conf->gen, &conf->gen.extra, newextra); set_guc_source(&conf->gen, source); conf->gen.scontext = context; conf->gen.srole = srole; } if (makeDefault) { GucStack *stack; if (conf->gen.reset_source <= source) { conf->reset_val = newval; set_extra_field(&conf->gen, &conf->reset_extra, newextra); conf->gen.reset_source = source; conf->gen.reset_scontext = context; conf->gen.reset_srole = srole; } for (stack = conf->gen.stack; stack; stack = stack->prev) { if (stack->source <= source) { stack->prior.val.enumval = newval; set_extra_field(&conf->gen, &stack->prior.extra, newextra); stack->source = source; stack->scontext = context; stack->srole = srole; } } } /* Perhaps we didn't install newextra anywhere */ if (newextra && !extra_field_used(&conf->gen, newextra)) guc_free(newextra); break; #undef newval } } if (changeVal && (record->flags & GUC_REPORT) && !(record->status & GUC_NEEDS_REPORT)) { record->status |= GUC_NEEDS_REPORT; slist_push_head(&guc_report_list, &record->report_link); } return changeVal ? 1 : -1; } /* * Retrieve a config_handle for the given name, suitable for calling * set_config_with_handle(). Only return handle to permanent GUC. */ config_handle * get_config_handle(const char *name) { struct config_generic *gen = find_option(name, false, false, 0); if (gen && ((gen->flags & GUC_CUSTOM_PLACEHOLDER) == 0)) return gen; return NULL; } /* * Set the fields for source file and line number the setting came from. */ static void set_config_sourcefile(const char *name, char *sourcefile, int sourceline) { struct config_generic *record; int elevel; /* * To avoid cluttering the log, only the postmaster bleats loudly about * problems with the config file. */ elevel = IsUnderPostmaster ? DEBUG3 : LOG; record = find_option(name, true, false, elevel); /* should not happen */ if (record == NULL) return; sourcefile = guc_strdup(elevel, sourcefile); guc_free(record->sourcefile); record->sourcefile = sourcefile; record->sourceline = sourceline; } /* * Set a config option to the given value. * * See also set_config_option; this is just the wrapper to be called from * outside GUC. (This function should be used when possible, because its API * is more stable than set_config_option's.) * * Note: there is no support here for setting source file/line, as it * is currently not needed. */ void SetConfigOption(const char *name, const char *value, GucContext context, GucSource source) { (void) set_config_option(name, value, context, source, GUC_ACTION_SET, true, 0, false); } /* * Fetch the current value of the option `name', as a string. * * If the option doesn't exist, return NULL if missing_ok is true, * otherwise throw an ereport and don't return. * * If restrict_privileged is true, we also enforce that only superusers and * members of the pg_read_all_settings role 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, bool missing_ok, bool restrict_privileged) { struct config_generic *record; static char buffer[256]; record = find_option(name, false, missing_ok, ERROR); if (record == NULL) return NULL; if (restrict_privileged && !ConfigOptionIsVisible(record)) ereport(ERROR, (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE), errmsg("permission denied to examine \"%s\"", name), errdetail("Only roles with privileges of the \"%s\" role may examine this parameter.", "pg_read_all_settings"))); switch (record->vartype) { case PGC_BOOL: return *((struct config_bool *) record)->variable ? "on" : "off"; case PGC_INT: snprintf(buffer, sizeof(buffer), "%d", *((struct config_int *) record)->variable); return buffer; case PGC_REAL: snprintf(buffer, sizeof(buffer), "%g", *((struct config_real *) record)->variable); return buffer; case PGC_STRING: return *((struct config_string *) record)->variable ? *((struct config_string *) record)->variable : ""; case PGC_ENUM: return config_enum_lookup_by_value((struct config_enum *) record, *((struct config_enum *) record)->variable); } return NULL; } /* * Get the RESET value associated with the given option. * * Note: this is not re-entrant, due to use of static result buffer; * not to mention that a string variable could have its reset_val changed. * Beware of assuming the result value is good for very long. */ const char * GetConfigOptionResetString(const char *name) { struct config_generic *record; static char buffer[256]; record = find_option(name, false, false, ERROR); Assert(record != NULL); if (!ConfigOptionIsVisible(record)) ereport(ERROR, (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE), errmsg("permission denied to examine \"%s\"", name), errdetail("Only roles with privileges of the \"%s\" role may examine this parameter.", "pg_read_all_settings"))); switch (record->vartype) { case PGC_BOOL: return ((struct config_bool *) record)->reset_val ? "on" : "off"; case PGC_INT: snprintf(buffer, sizeof(buffer), "%d", ((struct config_int *) record)->reset_val); return buffer; case PGC_REAL: snprintf(buffer, sizeof(buffer), "%g", ((struct config_real *) record)->reset_val); return buffer; case PGC_STRING: return ((struct config_string *) record)->reset_val ? ((struct config_string *) record)->reset_val : ""; case PGC_ENUM: return config_enum_lookup_by_value((struct config_enum *) record, ((struct config_enum *) record)->reset_val); } return NULL; } /* * Get the GUC flags associated with the given option. * * If the option doesn't exist, return 0 if missing_ok is true, * otherwise throw an ereport and don't return. */ int GetConfigOptionFlags(const char *name, bool missing_ok) { struct config_generic *record; record = find_option(name, false, missing_ok, ERROR); if (record == NULL) return 0; return record->flags; } /* * Write updated configuration parameter values into a temporary file. * This function traverses the list of parameters and quotes the string * values before writing them. */ static void write_auto_conf_file(int fd, const char *filename, ConfigVariable *head) { StringInfoData buf; ConfigVariable *item; initStringInfo(&buf); /* Emit file header containing warning comment */ appendStringInfoString(&buf, "# Do not edit this file manually!\n"); appendStringInfoString(&buf, "# It will be overwritten by the ALTER SYSTEM command.\n"); errno = 0; if (write(fd, buf.data, buf.len) != buf.len) { /* if write didn't set errno, assume problem is no disk space */ if (errno == 0) errno = ENOSPC; ereport(ERROR, (errcode_for_file_access(), errmsg("could not write to file \"%s\": %m", filename))); } /* Emit each parameter, properly quoting the value */ for (item = head; item != NULL; item = item->next) { char *escaped; resetStringInfo(&buf); appendStringInfoString(&buf, item->name); appendStringInfoString(&buf, " = '"); escaped = escape_single_quotes_ascii(item->value); if (!escaped) ereport(ERROR, (errcode(ERRCODE_OUT_OF_MEMORY), errmsg("out of memory"))); appendStringInfoString(&buf, escaped); free(escaped); appendStringInfoString(&buf, "'\n"); errno = 0; if (write(fd, buf.data, buf.len) != buf.len) { /* if write didn't set errno, assume problem is no disk space */ if (errno == 0) errno = ENOSPC; ereport(ERROR, (errcode_for_file_access(), errmsg("could not write to file \"%s\": %m", filename))); } } /* fsync before considering the write to be successful */ if (pg_fsync(fd) != 0) ereport(ERROR, (errcode_for_file_access(), errmsg("could not fsync file \"%s\": %m", filename))); pfree(buf.data); } /* * Update the given list of configuration parameters, adding, replacing * or deleting the entry for item "name" (delete if "value" == NULL). */ static void replace_auto_config_value(ConfigVariable **head_p, ConfigVariable **tail_p, const char *name, const char *value) { ConfigVariable *item, *next, *prev = NULL; /* * Remove any existing match(es) for "name". Normally there'd be at most * one, but if external tools have modified the config file, there could * be more. */ for (item = *head_p; item != NULL; item = next) { next = item->next; if (guc_name_compare(item->name, name) == 0) { /* found a match, delete it */ if (prev) prev->next = next; else *head_p = next; if (next == NULL) *tail_p = prev; pfree(item->name); pfree(item->value); pfree(item->filename); pfree(item); } else prev = item; } /* Done if we're trying to delete it */ if (value == NULL) return; /* OK, append a new entry */ item = palloc(sizeof *item); item->name = pstrdup(name); item->value = pstrdup(value); item->errmsg = NULL; item->filename = pstrdup(""); /* new item has no location */ item->sourceline = 0; item->ignore = false; item->applied = false; item->next = NULL; if (*head_p == NULL) *head_p = item; else (*tail_p)->next = item; *tail_p = item; } /* * Execute ALTER SYSTEM statement. * * Read the old PG_AUTOCONF_FILENAME file, merge in the new variable value, * and write out an updated file. If the command is ALTER SYSTEM RESET ALL, * we can skip reading the old file and just write an empty file. * * An LWLock is used to serialize updates of the configuration file. * * In case of an error, we leave the original automatic * configuration file (PG_AUTOCONF_FILENAME) intact. */ void AlterSystemSetConfigFile(AlterSystemStmt *altersysstmt) { char *name; char *value; bool resetall = false; ConfigVariable *head = NULL; ConfigVariable *tail = NULL; volatile int Tmpfd; char AutoConfFileName[MAXPGPATH]; char AutoConfTmpFileName[MAXPGPATH]; /* * Extract statement arguments */ name = altersysstmt->setstmt->name; if (!AllowAlterSystem) ereport(ERROR, (errcode(ERRCODE_FEATURE_NOT_SUPPORTED), errmsg("ALTER SYSTEM is not allowed in this environment"))); switch (altersysstmt->setstmt->kind) { case VAR_SET_VALUE: value = ExtractSetVariableArgs(altersysstmt->setstmt); break; case VAR_SET_DEFAULT: case VAR_RESET: value = NULL; break; case VAR_RESET_ALL: value = NULL; resetall = true; break; default: elog(ERROR, "unrecognized alter system stmt type: %d", altersysstmt->setstmt->kind); break; } /* * Check permission to run ALTER SYSTEM on the target variable */ if (!superuser()) { if (resetall) ereport(ERROR, (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE), errmsg("permission denied to perform ALTER SYSTEM RESET ALL"))); else { AclResult aclresult; aclresult = pg_parameter_aclcheck(name, GetUserId(), ACL_ALTER_SYSTEM); if (aclresult != ACLCHECK_OK) ereport(ERROR, (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE), errmsg("permission denied to set parameter \"%s\"", name))); } } /* * Unless it's RESET_ALL, validate the target variable and value */ if (!resetall) { struct config_generic *record; /* We don't want to create a placeholder if there's not one already */ record = find_option(name, false, true, DEBUG5); if (record != NULL) { /* * Don't allow parameters that can't be set in configuration files * to be set in PG_AUTOCONF_FILENAME file. */ if ((record->context == PGC_INTERNAL) || (record->flags & GUC_DISALLOW_IN_FILE) || (record->flags & GUC_DISALLOW_IN_AUTO_FILE)) ereport(ERROR, (errcode(ERRCODE_CANT_CHANGE_RUNTIME_PARAM), errmsg("parameter \"%s\" cannot be changed", name))); /* * If a value is specified, verify that it's sane. */ if (value) { union config_var_val newval; void *newextra = NULL; if (!parse_and_validate_value(record, value, PGC_S_FILE, ERROR, &newval, &newextra)) ereport(ERROR, (errcode(ERRCODE_INVALID_PARAMETER_VALUE), errmsg("invalid value for parameter \"%s\": \"%s\"", name, value))); if (record->vartype == PGC_STRING && newval.stringval != NULL) guc_free(newval.stringval); guc_free(newextra); } } else { /* * Variable not known; check we'd be allowed to create it. (We * cannot validate the value, but that's fine. A non-core GUC in * the config file cannot cause postmaster start to fail, so we * don't have to be too tense about possibly installing a bad * value.) */ (void) assignable_custom_variable_name(name, false, ERROR); } /* * We must also reject values containing newlines, because the grammar * for config files doesn't support embedded newlines in string * literals. */ if (value && strchr(value, '\n')) ereport(ERROR, (errcode(ERRCODE_INVALID_PARAMETER_VALUE), errmsg("parameter value for ALTER SYSTEM must not contain a newline"))); } /* * PG_AUTOCONF_FILENAME and its corresponding temporary file are always in * the data directory, so we can reference them by simple relative paths. */ snprintf(AutoConfFileName, sizeof(AutoConfFileName), "%s", PG_AUTOCONF_FILENAME); snprintf(AutoConfTmpFileName, sizeof(AutoConfTmpFileName), "%s.%s", AutoConfFileName, "tmp"); /* * Only one backend is allowed to operate on PG_AUTOCONF_FILENAME at a * time. Use AutoFileLock to ensure that. We must hold the lock while * reading the old file contents. */ LWLockAcquire(AutoFileLock, LW_EXCLUSIVE); /* * If we're going to reset everything, then no need to open or parse the * old file. We'll just write out an empty list. */ if (!resetall) { struct stat st; if (stat(AutoConfFileName, &st) == 0) { /* open old file PG_AUTOCONF_FILENAME */ FILE *infile; infile = AllocateFile(AutoConfFileName, "r"); if (infile == NULL) ereport(ERROR, (errcode_for_file_access(), errmsg("could not open file \"%s\": %m", AutoConfFileName))); /* parse it */ if (!ParseConfigFp(infile, AutoConfFileName, CONF_FILE_START_DEPTH, LOG, &head, &tail)) ereport(ERROR, (errcode(ERRCODE_CONFIG_FILE_ERROR), errmsg("could not parse contents of file \"%s\"", AutoConfFileName))); FreeFile(infile); } /* * Now, replace any existing entry with the new value, or add it if * not present. */ replace_auto_config_value(&head, &tail, name, value); } /* * Invoke the post-alter hook for setting this GUC variable. GUCs * typically do not have corresponding entries in pg_parameter_acl, so we * call the hook using the name rather than a potentially-non-existent * OID. Nonetheless, we pass ParameterAclRelationId so that this call * context can be distinguished from others. (Note that "name" will be * NULL in the RESET ALL case.) * * We do this here rather than at the end, because ALTER SYSTEM is not * transactional. If the hook aborts our transaction, it will be cleaner * to do so before we touch any files. */ InvokeObjectPostAlterHookArgStr(ParameterAclRelationId, name, ACL_ALTER_SYSTEM, altersysstmt->setstmt->kind, false); /* * To ensure crash safety, first write the new file data to a temp file, * then atomically rename it into place. * * If there is a temp file left over due to a previous crash, it's okay to * truncate and reuse it. */ Tmpfd = BasicOpenFile(AutoConfTmpFileName, O_CREAT | O_RDWR | O_TRUNC); if (Tmpfd < 0) ereport(ERROR, (errcode_for_file_access(), errmsg("could not open file \"%s\": %m", AutoConfTmpFileName))); /* * Use a TRY block to clean up the file if we fail. Since we need a TRY * block anyway, OK to use BasicOpenFile rather than OpenTransientFile. */ PG_TRY(); { /* Write and sync the new contents to the temporary file */ write_auto_conf_file(Tmpfd, AutoConfTmpFileName, head); /* Close before renaming; may be required on some platforms */ close(Tmpfd); Tmpfd = -1; /* * As the rename is atomic operation, if any problem occurs after this * at worst it can lose the parameters set by last ALTER SYSTEM * command. */ durable_rename(AutoConfTmpFileName, AutoConfFileName, ERROR); } PG_CATCH(); { /* Close file first, else unlink might fail on some platforms */ if (Tmpfd >= 0) close(Tmpfd); /* Unlink, but ignore any error */ (void) unlink(AutoConfTmpFileName); PG_RE_THROW(); } PG_END_TRY(); FreeConfigVariables(head); LWLockRelease(AutoFileLock); } /* * Common code for DefineCustomXXXVariable subroutines: allocate the * new variable's config struct and fill in generic fields. */ static struct config_generic * init_custom_variable(const char *name, const char *short_desc, const char *long_desc, GucContext context, int flags, enum config_type type, size_t sz) { 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"); /* * We can't support custom GUC_LIST_QUOTE variables, because the wrong * things would happen if such a variable were set or pg_dump'd when the * defining extension isn't loaded. Again, treat this as fatal because * the loadable module may be partly initialized already. */ if (flags & GUC_LIST_QUOTE) elog(FATAL, "extensions cannot define GUC_LIST_QUOTE variables"); /* * Before pljava commit 398f3b876ed402bdaec8bc804f29e2be95c75139 * (2015-12-15), two of that module's PGC_USERSET variables facilitated * trivial escalation to superuser privileges. Restrict the variables to * protect sites that have yet to upgrade pljava. */ if (context == PGC_USERSET && (strcmp(name, "pljava.classpath") == 0 || strcmp(name, "pljava.vmoptions") == 0)) context = PGC_SUSET; /* As above, an OOM here is FATAL */ gen = (struct config_generic *) guc_malloc(FATAL, sz); memset(gen, 0, sz); gen->name = guc_strdup(FATAL, name); gen->context = context; gen->group = CUSTOM_OPTIONS; gen->short_desc = short_desc; gen->long_desc = long_desc; gen->flags = flags; gen->vartype = type; return gen; } /* * Common code for DefineCustomXXXVariable subroutines: insert the new * variable into the GUC variable hash, replacing any placeholder. */ static void define_custom_variable(struct config_generic *variable) { const char *name = variable->name; GUCHashEntry *hentry; struct config_string *pHolder; /* Check mapping between initial and default value */ Assert(check_GUC_init(variable)); /* * See if there's a placeholder by the same name. */ hentry = (GUCHashEntry *) hash_search(guc_hashtab, &name, HASH_FIND, NULL); if (hentry == NULL) { /* * No placeholder to replace, so we can just add it ... but first, * make sure it's initialized to its default value. */ InitializeOneGUCOption(variable); add_guc_variable(variable, ERROR); return; } /* * This better be a placeholder */ if ((hentry->gucvar->flags & GUC_CUSTOM_PLACEHOLDER) == 0) ereport(ERROR, (errcode(ERRCODE_INTERNAL_ERROR), errmsg("attempt to redefine parameter \"%s\"", name))); Assert(hentry->gucvar->vartype == PGC_STRING); pHolder = (struct config_string *) hentry->gucvar; /* * First, set the variable to its default value. We must do this even * though we intend to immediately apply a new value, since it's possible * that the new value is invalid. */ InitializeOneGUCOption(variable); /* * Replace the placeholder in the hash table. We aren't changing the name * (at least up to case-folding), so the hash value is unchanged. */ hentry->gucname = name; hentry->gucvar = variable; /* * Remove the placeholder from any lists it's in, too. */ RemoveGUCFromLists(&pHolder->gen); /* * Assign the string value(s) stored in the placeholder to the real * variable. Essentially, we need to duplicate all the active and stacked * values, but with appropriate validation and datatype adjustment. * * If an assignment fails, we report a WARNING and keep going. We don't * want to throw ERROR for bad values, because it'd bollix the add-on * module that's presumably halfway through getting loaded. In such cases * the default or previous state will become active instead. */ /* First, apply the reset value if any */ if (pHolder->reset_val) (void) set_config_option_ext(name, pHolder->reset_val, pHolder->gen.reset_scontext, pHolder->gen.reset_source, pHolder->gen.reset_srole, GUC_ACTION_SET, true, WARNING, false); /* That should not have resulted in stacking anything */ Assert(variable->stack == NULL); /* Now, apply current and stacked values, in the order they were stacked */ reapply_stacked_values(variable, pHolder, pHolder->gen.stack, *(pHolder->variable), pHolder->gen.scontext, pHolder->gen.source, pHolder->gen.srole); /* 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. * (This neglects any stack items, so it's possible for some memory to be * leaked. Since this can only happen once per session per variable, it * doesn't seem worth spending much code on.) */ set_string_field(pHolder, pHolder->variable, NULL); set_string_field(pHolder, &pHolder->reset_val, NULL); guc_free(pHolder); } /* * Recursive subroutine for define_custom_variable: reapply non-reset values * * We recurse so that the values are applied in the same order as originally. * At each recursion level, apply the upper-level value (passed in) in the * fashion implied by the stack entry. */ static void reapply_stacked_values(struct config_generic *variable, struct config_string *pHolder, GucStack *stack, const char *curvalue, GucContext curscontext, GucSource cursource, Oid cursrole) { const char *name = variable->name; GucStack *oldvarstack = variable->stack; if (stack != NULL) { /* First, recurse, so that stack items are processed bottom to top */ reapply_stacked_values(variable, pHolder, stack->prev, stack->prior.val.stringval, stack->scontext, stack->source, stack->srole); /* See how to apply the passed-in value */ switch (stack->state) { case GUC_SAVE: (void) set_config_option_ext(name, curvalue, curscontext, cursource, cursrole, GUC_ACTION_SAVE, true, WARNING, false); break; case GUC_SET: (void) set_config_option_ext(name, curvalue, curscontext, cursource, cursrole, GUC_ACTION_SET, true, WARNING, false); break; case GUC_LOCAL: (void) set_config_option_ext(name, curvalue, curscontext, cursource, cursrole, GUC_ACTION_LOCAL, true, WARNING, false); break; case GUC_SET_LOCAL: /* first, apply the masked value as SET */ (void) set_config_option_ext(name, stack->masked.val.stringval, stack->masked_scontext, PGC_S_SESSION, stack->masked_srole, GUC_ACTION_SET, true, WARNING, false); /* then apply the current value as LOCAL */ (void) set_config_option_ext(name, curvalue, curscontext, cursource, cursrole, GUC_ACTION_LOCAL, true, WARNING, false); break; } /* If we successfully made a stack entry, adjust its nest level */ if (variable->stack != oldvarstack) variable->stack->nest_level = stack->nest_level; } else { /* * We are at the end of the stack. If the active/previous value is * different from the reset value, it must represent a previously * committed session value. Apply it, and then drop the stack entry * that set_config_option will have created under the impression that * this is to be just a transactional assignment. (We leak the stack * entry.) */ if (curvalue != pHolder->reset_val || curscontext != pHolder->gen.reset_scontext || cursource != pHolder->gen.reset_source || cursrole != pHolder->gen.reset_srole) { (void) set_config_option_ext(name, curvalue, curscontext, cursource, cursrole, GUC_ACTION_SET, true, WARNING, false); if (variable->stack != NULL) { slist_delete(&guc_stack_list, &variable->stack_link); variable->stack = NULL; } } } } /* * Functions for extensions to call to define their custom GUC variables. */ void DefineCustomBoolVariable(const char *name, const char *short_desc, const char *long_desc, bool *valueAddr, bool bootValue, GucContext context, int flags, GucBoolCheckHook check_hook, GucBoolAssignHook assign_hook, GucShowHook show_hook) { struct config_bool *var; var = (struct config_bool *) init_custom_variable(name, short_desc, long_desc, context, flags, PGC_BOOL, sizeof(struct config_bool)); var->variable = valueAddr; var->boot_val = bootValue; var->reset_val = bootValue; var->check_hook = check_hook; var->assign_hook = assign_hook; var->show_hook = show_hook; define_custom_variable(&var->gen); } void DefineCustomIntVariable(const char *name, const char *short_desc, const char *long_desc, int *valueAddr, int bootValue, int minValue, int maxValue, GucContext context, int flags, GucIntCheckHook check_hook, GucIntAssignHook assign_hook, GucShowHook show_hook) { struct config_int *var; var = (struct config_int *) init_custom_variable(name, short_desc, long_desc, context, flags, PGC_INT, sizeof(struct config_int)); var->variable = valueAddr; var->boot_val = bootValue; var->reset_val = bootValue; var->min = minValue; var->max = maxValue; var->check_hook = check_hook; var->assign_hook = assign_hook; var->show_hook = show_hook; define_custom_variable(&var->gen); } void DefineCustomRealVariable(const char *name, const char *short_desc, const char *long_desc, double *valueAddr, double bootValue, double minValue, double maxValue, GucContext context, int flags, GucRealCheckHook check_hook, GucRealAssignHook assign_hook, GucShowHook show_hook) { struct config_real *var; var = (struct config_real *) init_custom_variable(name, short_desc, long_desc, context, flags, PGC_REAL, sizeof(struct config_real)); var->variable = valueAddr; var->boot_val = bootValue; var->reset_val = bootValue; var->min = minValue; var->max = maxValue; var->check_hook = check_hook; var->assign_hook = assign_hook; var->show_hook = show_hook; define_custom_variable(&var->gen); } void DefineCustomStringVariable(const char *name, const char *short_desc, const char *long_desc, char **valueAddr, const char *bootValue, GucContext context, int flags, GucStringCheckHook check_hook, GucStringAssignHook assign_hook, GucShowHook show_hook) { struct config_string *var; var = (struct config_string *) init_custom_variable(name, short_desc, long_desc, context, flags, PGC_STRING, sizeof(struct config_string)); var->variable = valueAddr; var->boot_val = bootValue; var->check_hook = check_hook; var->assign_hook = assign_hook; var->show_hook = show_hook; define_custom_variable(&var->gen); } void DefineCustomEnumVariable(const char *name, const char *short_desc, const char *long_desc, int *valueAddr, int bootValue, const struct config_enum_entry *options, GucContext context, int flags, GucEnumCheckHook check_hook, GucEnumAssignHook assign_hook, GucShowHook show_hook) { struct config_enum *var; var = (struct config_enum *) init_custom_variable(name, short_desc, long_desc, context, flags, PGC_ENUM, sizeof(struct config_enum)); var->variable = valueAddr; var->boot_val = bootValue; var->reset_val = bootValue; var->options = options; var->check_hook = check_hook; var->assign_hook = assign_hook; var->show_hook = show_hook; define_custom_variable(&var->gen); } /* * Mark the given GUC prefix as "reserved". * * This deletes any existing placeholders matching the prefix, * and then prevents new ones from being created. * Extensions should call this after they've defined all of their custom * GUCs, to help catch misspelled config-file entries. */ void MarkGUCPrefixReserved(const char *className) { int classLen = strlen(className); HASH_SEQ_STATUS status; GUCHashEntry *hentry; MemoryContext oldcontext; /* * Check for existing placeholders. We must actually remove invalid * placeholders, else future parallel worker startups will fail. (We * don't bother trying to free associated memory, since this shouldn't * happen often.) */ hash_seq_init(&status, guc_hashtab); while ((hentry = (GUCHashEntry *) hash_seq_search(&status)) != NULL) { struct config_generic *var = hentry->gucvar; if ((var->flags & GUC_CUSTOM_PLACEHOLDER) != 0 && strncmp(className, var->name, classLen) == 0 && var->name[classLen] == GUC_QUALIFIER_SEPARATOR) { ereport(WARNING, (errcode(ERRCODE_INVALID_NAME), errmsg("invalid configuration parameter name \"%s\", removing it", var->name), errdetail("\"%s\" is now a reserved prefix.", className))); /* Remove it from the hash table */ hash_search(guc_hashtab, &var->name, HASH_REMOVE, NULL); /* Remove it from any lists it's in, too */ RemoveGUCFromLists(var); } } /* And remember the name so we can prevent future mistakes. */ oldcontext = MemoryContextSwitchTo(GUCMemoryContext); reserved_class_prefix = lappend(reserved_class_prefix, pstrdup(className)); MemoryContextSwitchTo(oldcontext); } /* * Return an array of modified GUC options to show in EXPLAIN. * * We only report options related to query planning (marked with GUC_EXPLAIN), * with values different from their built-in defaults. */ struct config_generic ** get_explain_guc_options(int *num) { struct config_generic **result; dlist_iter iter; *num = 0; /* * While only a fraction of all the GUC variables are marked GUC_EXPLAIN, * it doesn't seem worth dynamically resizing this array. */ result = palloc(sizeof(struct config_generic *) * hash_get_num_entries(guc_hashtab)); /* We need only consider GUCs with source not PGC_S_DEFAULT */ dlist_foreach(iter, &guc_nondef_list) { struct config_generic *conf = dlist_container(struct config_generic, nondef_link, iter.cur); bool modified; /* return only parameters marked for inclusion in explain */ if (!(conf->flags & GUC_EXPLAIN)) continue; /* return only options visible to the current user */ if (!ConfigOptionIsVisible(conf)) continue; /* return only options that are different from their boot values */ modified = false; switch (conf->vartype) { case PGC_BOOL: { struct config_bool *lconf = (struct config_bool *) conf; modified = (lconf->boot_val != *(lconf->variable)); } break; case PGC_INT: { struct config_int *lconf = (struct config_int *) conf; modified = (lconf->boot_val != *(lconf->variable)); } break; case PGC_REAL: { struct config_real *lconf = (struct config_real *) conf; modified = (lconf->boot_val != *(lconf->variable)); } break; case PGC_STRING: { struct config_string *lconf = (struct config_string *) conf; if (lconf->boot_val == NULL && *lconf->variable == NULL) modified = false; else if (lconf->boot_val == NULL || *lconf->variable == NULL) modified = true; else modified = (strcmp(lconf->boot_val, *(lconf->variable)) != 0); } break; case PGC_ENUM: { struct config_enum *lconf = (struct config_enum *) conf; modified = (lconf->boot_val != *(lconf->variable)); } break; default: elog(ERROR, "unexpected GUC type: %d", conf->vartype); } if (!modified) continue; /* OK, report it */ result[*num] = conf; *num = *num + 1; } return result; } /* * Return GUC variable value by name; optionally return canonical form of * name. If the GUC is unset, then throw an error unless missing_ok is true, * in which case return NULL. Return value is palloc'd (but *varname isn't). */ char * GetConfigOptionByName(const char *name, const char **varname, bool missing_ok) { struct config_generic *record; record = find_option(name, false, missing_ok, ERROR); if (record == NULL) { if (varname) *varname = NULL; return NULL; } if (!ConfigOptionIsVisible(record)) ereport(ERROR, (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE), errmsg("permission denied to examine \"%s\"", name), errdetail("Only roles with privileges of the \"%s\" role may examine this parameter.", "pg_read_all_settings"))); if (varname) *varname = record->name; return ShowGUCOption(record, true); } /* * ShowGUCOption: get string value of variable * * We express a numeric value in appropriate units if it has units and * use_units is true; else you just get the raw number. * The result string is palloc'd. */ char * ShowGUCOption(struct config_generic *record, bool use_units) { char buffer[256]; const char *val; switch (record->vartype) { case PGC_BOOL: { struct config_bool *conf = (struct config_bool *) record; if (conf->show_hook) val = conf->show_hook(); else val = *conf->variable ? "on" : "off"; } break; case PGC_INT: { struct config_int *conf = (struct config_int *) record; if (conf->show_hook) val = conf->show_hook(); else { /* * Use int64 arithmetic to avoid overflows in units * conversion. */ int64 result = *conf->variable; const char *unit; if (use_units && result > 0 && (record->flags & GUC_UNIT)) convert_int_from_base_unit(result, record->flags & GUC_UNIT, &result, &unit); else unit = ""; snprintf(buffer, sizeof(buffer), INT64_FORMAT "%s", result, unit); val = buffer; } } break; case PGC_REAL: { struct config_real *conf = (struct config_real *) record; if (conf->show_hook) val = conf->show_hook(); else { double result = *conf->variable; const char *unit; if (use_units && result > 0 && (record->flags & GUC_UNIT)) convert_real_from_base_unit(result, record->flags & GUC_UNIT, &result, &unit); else unit = ""; snprintf(buffer, sizeof(buffer), "%g%s", result, unit); val = buffer; } } break; case PGC_STRING: { struct config_string *conf = (struct config_string *) record; if (conf->show_hook) val = conf->show_hook(); else if (*conf->variable && **conf->variable) val = *conf->variable; else val = ""; } break; case PGC_ENUM: { struct config_enum *conf = (struct config_enum *) record; if (conf->show_hook) val = conf->show_hook(); else val = config_enum_lookup_by_value(conf, *conf->variable); } break; default: /* just to keep compiler quiet */ val = "???"; break; } return pstrdup(val); } #ifdef EXEC_BACKEND /* * 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 sourcefile, string, null terminated (empty if none) * variable sourceline, integer * variable source, integer * variable scontext, integer * variable srole, OID */ static void write_one_nondefault_variable(FILE *fp, struct config_generic *gconf) { Assert(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) 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; fprintf(fp, "%.17g", *conf->variable); } break; case PGC_STRING: { struct config_string *conf = (struct config_string *) gconf; if (*conf->variable) 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); if (gconf->sourcefile) fprintf(fp, "%s", gconf->sourcefile); fputc(0, fp); fwrite(&gconf->sourceline, 1, sizeof(gconf->sourceline), fp); fwrite(&gconf->source, 1, sizeof(gconf->source), fp); fwrite(&gconf->scontext, 1, sizeof(gconf->scontext), fp); fwrite(&gconf->srole, 1, sizeof(gconf->srole), fp); } void write_nondefault_variables(GucContext context) { int elevel; FILE *fp; dlist_iter iter; Assert(context == PGC_POSTMASTER || context == PGC_SIGHUP); elevel = (context == PGC_SIGHUP) ? LOG : ERROR; /* * Open file */ fp = AllocateFile(CONFIG_EXEC_PARAMS_NEW, "w"); if (!fp) { ereport(elevel, (errcode_for_file_access(), errmsg("could not write to file \"%s\": %m", CONFIG_EXEC_PARAMS_NEW))); return; } /* We need only consider GUCs with source not PGC_S_DEFAULT */ dlist_foreach(iter, &guc_nondef_list) { struct config_generic *gconf = dlist_container(struct config_generic, nondef_link, iter.cur); write_one_nondefault_variable(fp, gconf); } if (FreeFile(fp)) { ereport(elevel, (errcode_for_file_access(), errmsg("could not write to file \"%s\": %m", CONFIG_EXEC_PARAMS_NEW))); return; } /* * Put new file in place. This could delay on Win32, but we don't hold * any exclusive locks. */ rename(CONFIG_EXEC_PARAMS_NEW, CONFIG_EXEC_PARAMS); } /* * Read string, including null byte from file * * Return NULL on EOF and nothing read */ static char * read_string_with_null(FILE *fp) { int i = 0, ch, maxlen = 256; char *str = NULL; do { if ((ch = fgetc(fp)) == EOF) { if (i == 0) return NULL; else elog(FATAL, "invalid format of exec config params file"); } if (i == 0) str = guc_malloc(FATAL, maxlen); else if (i == maxlen) str = guc_realloc(FATAL, str, maxlen *= 2); str[i++] = ch; } while (ch != 0); return str; } /* * This routine loads a previous postmaster dump of its non-default * settings. */ void read_nondefault_variables(void) { FILE *fp; char *varname, *varvalue, *varsourcefile; int varsourceline; GucSource varsource; GucContext varscontext; Oid varsrole; /* * Open file */ fp = AllocateFile(CONFIG_EXEC_PARAMS, "r"); if (!fp) { /* File not found is fine */ if (errno != ENOENT) ereport(FATAL, (errcode_for_file_access(), errmsg("could not read from file \"%s\": %m", CONFIG_EXEC_PARAMS))); return; } for (;;) { if ((varname = read_string_with_null(fp)) == NULL) break; if (find_option(varname, true, false, FATAL) == NULL) elog(FATAL, "failed to locate variable \"%s\" in exec config params file", varname); if ((varvalue = read_string_with_null(fp)) == NULL) elog(FATAL, "invalid format of exec config params file"); if ((varsourcefile = read_string_with_null(fp)) == NULL) elog(FATAL, "invalid format of exec config params file"); if (fread(&varsourceline, 1, sizeof(varsourceline), fp) != sizeof(varsourceline)) elog(FATAL, "invalid format of exec config params file"); if (fread(&varsource, 1, sizeof(varsource), fp) != sizeof(varsource)) elog(FATAL, "invalid format of exec config params file"); if (fread(&varscontext, 1, sizeof(varscontext), fp) != sizeof(varscontext)) elog(FATAL, "invalid format of exec config params file"); if (fread(&varsrole, 1, sizeof(varsrole), fp) != sizeof(varsrole)) elog(FATAL, "invalid format of exec config params file"); (void) set_config_option_ext(varname, varvalue, varscontext, varsource, varsrole, GUC_ACTION_SET, true, 0, true); if (varsourcefile[0]) set_config_sourcefile(varname, varsourcefile, varsourceline); guc_free(varname); guc_free(varvalue); guc_free(varsourcefile); } FreeFile(fp); } #endif /* EXEC_BACKEND */ /* * can_skip_gucvar: * Decide whether SerializeGUCState can skip sending this GUC variable, * or whether RestoreGUCState can skip resetting this GUC to default. * * It is somewhat magical and fragile that the same test works for both cases. * Realize in particular that we are very likely selecting different sets of * GUCs on the leader and worker sides! Be sure you've understood the * comments here and in RestoreGUCState thoroughly before changing this. */ static bool can_skip_gucvar(struct config_generic *gconf) { /* * We can skip GUCs that are guaranteed to have the same values in leaders * and workers. (Note it is critical that the leader and worker have the * same idea of which GUCs fall into this category. It's okay to consider * context and name for this purpose, since those are unchanging * properties of a GUC.) * * PGC_POSTMASTER variables always have the same value in every child of a * particular postmaster, so the worker will certainly have the right * value already. Likewise, PGC_INTERNAL variables are set by special * mechanisms (if indeed they aren't compile-time constants). So we may * always skip these. * * For all other GUCs, we skip if the GUC has its compiled-in default * value (i.e., source == PGC_S_DEFAULT). On the leader side, this means * we don't send GUCs that have their default values, which typically * saves lots of work. On the worker side, this means we don't need to * reset the GUC to default because it already has that value. See * comments in RestoreGUCState for more info. */ return gconf->context == PGC_POSTMASTER || gconf->context == PGC_INTERNAL || gconf->source == PGC_S_DEFAULT; } /* * estimate_variable_size: * Compute space needed for dumping the given GUC variable. * * It's OK to overestimate, but not to underestimate. */ static Size estimate_variable_size(struct config_generic *gconf) { Size size; Size valsize = 0; /* Skippable GUCs consume zero space. */ if (can_skip_gucvar(gconf)) return 0; /* Name, plus trailing zero byte. */ size = strlen(gconf->name) + 1; /* Get the maximum display length of the GUC value. */ switch (gconf->vartype) { case PGC_BOOL: { valsize = 5; /* max(strlen('true'), strlen('false')) */ } break; case PGC_INT: { struct config_int *conf = (struct config_int *) gconf; /* * Instead of getting the exact display length, use max * length. Also reduce the max length for typical ranges of * small values. Maximum value is 2147483647, i.e. 10 chars. * Include one byte for sign. */ if (abs(*conf->variable) < 1000) valsize = 3 + 1; else valsize = 10 + 1; } break; case PGC_REAL: { /* * We are going to print it with %e with REALTYPE_PRECISION * fractional digits. Account for sign, leading digit, * decimal point, and exponent with up to 3 digits. E.g. * -3.99329042340000021e+110 */ valsize = 1 + 1 + 1 + REALTYPE_PRECISION + 5; } break; case PGC_STRING: { struct config_string *conf = (struct config_string *) gconf; /* * If the value is NULL, we transmit it as an empty string. * Although this is not physically the same value, GUC * generally treats a NULL the same as empty string. */ if (*conf->variable) valsize = strlen(*conf->variable); else valsize = 0; } break; case PGC_ENUM: { struct config_enum *conf = (struct config_enum *) gconf; valsize = strlen(config_enum_lookup_by_value(conf, *conf->variable)); } break; } /* Allow space for terminating zero-byte for value */ size = add_size(size, valsize + 1); if (gconf->sourcefile) size = add_size(size, strlen(gconf->sourcefile)); /* Allow space for terminating zero-byte for sourcefile */ size = add_size(size, 1); /* Include line whenever file is nonempty. */ if (gconf->sourcefile && gconf->sourcefile[0]) size = add_size(size, sizeof(gconf->sourceline)); size = add_size(size, sizeof(gconf->source)); size = add_size(size, sizeof(gconf->scontext)); size = add_size(size, sizeof(gconf->srole)); return size; } /* * EstimateGUCStateSpace: * Returns the size needed to store the GUC state for the current process */ Size EstimateGUCStateSpace(void) { Size size; dlist_iter iter; /* Add space reqd for saving the data size of the guc state */ size = sizeof(Size); /* * Add up the space needed for each GUC variable. * * We need only process non-default GUCs. */ dlist_foreach(iter, &guc_nondef_list) { struct config_generic *gconf = dlist_container(struct config_generic, nondef_link, iter.cur); size = add_size(size, estimate_variable_size(gconf)); } return size; } /* * do_serialize: * Copies the formatted string into the destination. Moves ahead the * destination pointer, and decrements the maxbytes by that many bytes. If * maxbytes is not sufficient to copy the string, error out. */ static void do_serialize(char **destptr, Size *maxbytes, const char *fmt,...) { va_list vargs; int n; if (*maxbytes <= 0) elog(ERROR, "not enough space to serialize GUC state"); va_start(vargs, fmt); n = vsnprintf(*destptr, *maxbytes, fmt, vargs); va_end(vargs); if (n < 0) { /* Shouldn't happen. Better show errno description. */ elog(ERROR, "vsnprintf failed: %m with format string \"%s\"", fmt); } if (n >= *maxbytes) { /* This shouldn't happen either, really. */ elog(ERROR, "not enough space to serialize GUC state"); } /* Shift the destptr ahead of the null terminator */ *destptr += n + 1; *maxbytes -= n + 1; } /* Binary copy version of do_serialize() */ static void do_serialize_binary(char **destptr, Size *maxbytes, void *val, Size valsize) { if (valsize > *maxbytes) elog(ERROR, "not enough space to serialize GUC state"); memcpy(*destptr, val, valsize); *destptr += valsize; *maxbytes -= valsize; } /* * serialize_variable: * Dumps name, value and other information of a GUC variable into destptr. */ static void serialize_variable(char **destptr, Size *maxbytes, struct config_generic *gconf) { /* Ignore skippable GUCs. */ if (can_skip_gucvar(gconf)) return; do_serialize(destptr, maxbytes, "%s", gconf->name); switch (gconf->vartype) { case PGC_BOOL: { struct config_bool *conf = (struct config_bool *) gconf; do_serialize(destptr, maxbytes, (*conf->variable ? "true" : "false")); } break; case PGC_INT: { struct config_int *conf = (struct config_int *) gconf; do_serialize(destptr, maxbytes, "%d", *conf->variable); } break; case PGC_REAL: { struct config_real *conf = (struct config_real *) gconf; do_serialize(destptr, maxbytes, "%.*e", REALTYPE_PRECISION, *conf->variable); } break; case PGC_STRING: { struct config_string *conf = (struct config_string *) gconf; /* NULL becomes empty string, see estimate_variable_size() */ do_serialize(destptr, maxbytes, "%s", *conf->variable ? *conf->variable : ""); } break; case PGC_ENUM: { struct config_enum *conf = (struct config_enum *) gconf; do_serialize(destptr, maxbytes, "%s", config_enum_lookup_by_value(conf, *conf->variable)); } break; } do_serialize(destptr, maxbytes, "%s", (gconf->sourcefile ? gconf->sourcefile : "")); if (gconf->sourcefile && gconf->sourcefile[0]) do_serialize_binary(destptr, maxbytes, &gconf->sourceline, sizeof(gconf->sourceline)); do_serialize_binary(destptr, maxbytes, &gconf->source, sizeof(gconf->source)); do_serialize_binary(destptr, maxbytes, &gconf->scontext, sizeof(gconf->scontext)); do_serialize_binary(destptr, maxbytes, &gconf->srole, sizeof(gconf->srole)); } /* * SerializeGUCState: * Dumps the complete GUC state onto the memory location at start_address. */ void SerializeGUCState(Size maxsize, char *start_address) { char *curptr; Size actual_size; Size bytes_left; dlist_iter iter; /* Reserve space for saving the actual size of the guc state */ Assert(maxsize > sizeof(actual_size)); curptr = start_address + sizeof(actual_size); bytes_left = maxsize - sizeof(actual_size); /* We need only consider GUCs with source not PGC_S_DEFAULT */ dlist_foreach(iter, &guc_nondef_list) { struct config_generic *gconf = dlist_container(struct config_generic, nondef_link, iter.cur); serialize_variable(&curptr, &bytes_left, gconf); } /* Store actual size without assuming alignment of start_address. */ actual_size = maxsize - bytes_left - sizeof(actual_size); memcpy(start_address, &actual_size, sizeof(actual_size)); } /* * read_gucstate: * Actually it does not read anything, just returns the srcptr. But it does * move the srcptr past the terminating zero byte, so that the caller is ready * to read the next string. */ static char * read_gucstate(char **srcptr, char *srcend) { char *retptr = *srcptr; char *ptr; if (*srcptr >= srcend) elog(ERROR, "incomplete GUC state"); /* The string variables are all null terminated */ for (ptr = *srcptr; ptr < srcend && *ptr != '\0'; ptr++) ; if (ptr >= srcend) elog(ERROR, "could not find null terminator in GUC state"); /* Set the new position to the byte following the terminating NUL */ *srcptr = ptr + 1; return retptr; } /* Binary read version of read_gucstate(). Copies into dest */ static void read_gucstate_binary(char **srcptr, char *srcend, void *dest, Size size) { if (*srcptr + size > srcend) elog(ERROR, "incomplete GUC state"); memcpy(dest, *srcptr, size); *srcptr += size; } /* * Callback used to add a context message when reporting errors that occur * while trying to restore GUCs in parallel workers. */ static void guc_restore_error_context_callback(void *arg) { char **error_context_name_and_value = (char **) arg; if (error_context_name_and_value) errcontext("while setting parameter \"%s\" to \"%s\"", error_context_name_and_value[0], error_context_name_and_value[1]); } /* * RestoreGUCState: * Reads the GUC state at the specified address and sets this process's * GUCs to match. * * Note that this provides the worker with only a very shallow view of the * leader's GUC state: we'll know about the currently active values, but not * about stacked or reset values. That's fine since the worker is just * executing one part of a query, within which the active values won't change * and the stacked values are invisible. */ void RestoreGUCState(void *gucstate) { char *varname, *varvalue, *varsourcefile; int varsourceline; GucSource varsource; GucContext varscontext; Oid varsrole; char *srcptr = (char *) gucstate; char *srcend; Size len; dlist_mutable_iter iter; ErrorContextCallback error_context_callback; /* * First, ensure that all potentially-shippable GUCs are reset to their * default values. We must not touch those GUCs that the leader will * never ship, while there is no need to touch those that are shippable * but already have their default values. Thus, this ends up being the * same test that SerializeGUCState uses, even though the sets of * variables involved may well be different since the leader's set of * variables-not-at-default-values can differ from the set that are * not-default in this freshly started worker. * * Once we have set all the potentially-shippable GUCs to default values, * restoring the GUCs that the leader sent (because they had non-default * values over there) leads us to exactly the set of GUC values that the * leader has. This is true even though the worker may have initially * absorbed postgresql.conf settings that the leader hasn't yet seen, or * ALTER USER/DATABASE SET settings that were established after the leader * started. * * Note that ensuring all the potential target GUCs are at PGC_S_DEFAULT * also ensures that set_config_option won't refuse to set them because of * source-priority comparisons. */ dlist_foreach_modify(iter, &guc_nondef_list) { struct config_generic *gconf = dlist_container(struct config_generic, nondef_link, iter.cur); /* Do nothing if non-shippable or if already at PGC_S_DEFAULT. */ if (can_skip_gucvar(gconf)) continue; /* * We can use InitializeOneGUCOption to reset the GUC to default, but * first we must free any existing subsidiary data to avoid leaking * memory. The stack must be empty, but we have to clean up all other * fields. Beware that there might be duplicate value or "extra" * pointers. We also have to be sure to take it out of any lists it's * in. */ Assert(gconf->stack == NULL); guc_free(gconf->extra); guc_free(gconf->last_reported); guc_free(gconf->sourcefile); switch (gconf->vartype) { case PGC_BOOL: { struct config_bool *conf = (struct config_bool *) gconf; if (conf->reset_extra && conf->reset_extra != gconf->extra) guc_free(conf->reset_extra); break; } case PGC_INT: { struct config_int *conf = (struct config_int *) gconf; if (conf->reset_extra && conf->reset_extra != gconf->extra) guc_free(conf->reset_extra); break; } case PGC_REAL: { struct config_real *conf = (struct config_real *) gconf; if (conf->reset_extra && conf->reset_extra != gconf->extra) guc_free(conf->reset_extra); break; } case PGC_STRING: { struct config_string *conf = (struct config_string *) gconf; guc_free(*conf->variable); if (conf->reset_val && conf->reset_val != *conf->variable) guc_free(conf->reset_val); if (conf->reset_extra && conf->reset_extra != gconf->extra) guc_free(conf->reset_extra); break; } case PGC_ENUM: { struct config_enum *conf = (struct config_enum *) gconf; if (conf->reset_extra && conf->reset_extra != gconf->extra) guc_free(conf->reset_extra); break; } } /* Remove it from any lists it's in. */ RemoveGUCFromLists(gconf); /* Now we can reset the struct to PGS_S_DEFAULT state. */ InitializeOneGUCOption(gconf); } /* First item is the length of the subsequent data */ memcpy(&len, gucstate, sizeof(len)); srcptr += sizeof(len); srcend = srcptr + len; /* If the GUC value check fails, we want errors to show useful context. */ error_context_callback.callback = guc_restore_error_context_callback; error_context_callback.previous = error_context_stack; error_context_callback.arg = NULL; error_context_stack = &error_context_callback; /* Restore all the listed GUCs. */ while (srcptr < srcend) { int result; char *error_context_name_and_value[2]; varname = read_gucstate(&srcptr, srcend); varvalue = read_gucstate(&srcptr, srcend); varsourcefile = read_gucstate(&srcptr, srcend); if (varsourcefile[0]) read_gucstate_binary(&srcptr, srcend, &varsourceline, sizeof(varsourceline)); else varsourceline = 0; read_gucstate_binary(&srcptr, srcend, &varsource, sizeof(varsource)); read_gucstate_binary(&srcptr, srcend, &varscontext, sizeof(varscontext)); read_gucstate_binary(&srcptr, srcend, &varsrole, sizeof(varsrole)); error_context_name_and_value[0] = varname; error_context_name_and_value[1] = varvalue; error_context_callback.arg = &error_context_name_and_value[0]; result = set_config_option_ext(varname, varvalue, varscontext, varsource, varsrole, GUC_ACTION_SET, true, ERROR, true); if (result <= 0) ereport(ERROR, (errcode(ERRCODE_INTERNAL_ERROR), errmsg("parameter \"%s\" could not be set", varname))); if (varsourcefile[0]) set_config_sourcefile(varname, varsourcefile, varsourceline); error_context_callback.arg = NULL; } error_context_stack = error_context_callback.previous; } /* * A little "long argument" simulation, although not quite GNU * compliant. Takes a string of the form "some-option=some value" and * returns name = "some_option" and value = "some value" in palloc'ed * storage. Note that '-' is converted to '_' in the option name. If * there is no '=' in the input string then value will be NULL. */ void ParseLongOption(const char *string, char **name, char **value) { size_t equal_pos; char *cp; Assert(string); Assert(name); Assert(value); equal_pos = strcspn(string, "="); if (string[equal_pos] == '=') { *name = palloc(equal_pos + 1); strlcpy(*name, string, equal_pos + 1); *value = pstrdup(&string[equal_pos + 1]); } else { /* no equal sign in string */ *name = pstrdup(string); *value = NULL; } for (cp = *name; *cp; cp++) if (*cp == '-') *cp = '_'; } /* * Transform array of GUC settings into lists of names and values. The lists * are faster to process in cases where the settings must be applied * repeatedly (e.g. for each function invocation). */ void TransformGUCArray(ArrayType *array, List **names, List **values) { int i; Assert(array != NULL); Assert(ARR_ELEMTYPE(array) == TEXTOID); Assert(ARR_NDIM(array) == 1); Assert(ARR_LBOUND(array)[0] == 1); *names = NIL; *values = NIL; for (i = 1; i <= ARR_DIMS(array)[0]; i++) { Datum d; bool isnull; char *s; char *name; char *value; d = array_ref(array, 1, &i, -1 /* varlenarray */ , -1 /* TEXT's typlen */ , false /* TEXT's typbyval */ , TYPALIGN_INT /* TEXT's typalign */ , &isnull); if (isnull) continue; s = TextDatumGetCString(d); ParseLongOption(s, &name, &value); if (!value) { ereport(WARNING, (errcode(ERRCODE_SYNTAX_ERROR), errmsg("could not parse setting for parameter \"%s\"", name))); pfree(name); continue; } *names = lappend(*names, name); *values = lappend(*values, value); pfree(s); } } /* * Handle options fetched from pg_db_role_setting.setconfig, * pg_proc.proconfig, etc. Caller must specify proper context/source/action. * * The array parameter must be an array of TEXT (it must not be NULL). */ void ProcessGUCArray(ArrayType *array, GucContext context, GucSource source, GucAction action) { List *gucNames; List *gucValues; ListCell *lc1; ListCell *lc2; TransformGUCArray(array, &gucNames, &gucValues); forboth(lc1, gucNames, lc2, gucValues) { char *name = lfirst(lc1); char *value = lfirst(lc2); (void) set_config_option(name, value, context, source, action, true, 0, false); pfree(name); pfree(value); } list_free(gucNames); list_free(gucValues); } /* * Add an entry to an option array. The array parameter may be NULL * to indicate the current table entry is NULL. */ ArrayType * GUCArrayAdd(ArrayType *array, const char *name, const char *value) { struct config_generic *record; Datum datum; char *newval; ArrayType *a; Assert(name); Assert(value); /* test if the option is valid and we're allowed to set it */ (void) validate_option_array_item(name, value, false); /* normalize name (converts obsolete GUC names to modern spellings) */ record = find_option(name, false, true, WARNING); if (record) name = record->name; /* build new item for array */ newval = psprintf("%s=%s", name, value); datum = CStringGetTextDatum(newval); if (array) { int index; bool isnull; int i; Assert(ARR_ELEMTYPE(array) == TEXTOID); Assert(ARR_NDIM(array) == 1); Assert(ARR_LBOUND(array)[0] == 1); index = ARR_DIMS(array)[0] + 1; /* add after end */ for (i = 1; i <= ARR_DIMS(array)[0]; i++) { Datum d; char *current; d = array_ref(array, 1, &i, -1 /* varlenarray */ , -1 /* TEXT's typlen */ , false /* TEXT's typbyval */ , TYPALIGN_INT /* TEXT's typalign */ , &isnull); if (isnull) continue; current = TextDatumGetCString(d); /* check for match up through and including '=' */ if (strncmp(current, newval, strlen(name) + 1) == 0) { index = i; break; } } a = array_set(array, 1, &index, datum, false, -1 /* varlena array */ , -1 /* TEXT's typlen */ , false /* TEXT's typbyval */ , TYPALIGN_INT /* TEXT's typalign */ ); } else a = construct_array_builtin(&datum, 1, TEXTOID); return a; } /* * Delete an entry from an option array. The array parameter may be NULL * to indicate the current table entry is NULL. Also, if the return value * is NULL then a null should be stored. */ ArrayType * GUCArrayDelete(ArrayType *array, const char *name) { struct config_generic *record; ArrayType *newarray; int i; int index; Assert(name); /* test if the option is valid and we're allowed to set it */ (void) validate_option_array_item(name, NULL, false); /* normalize name (converts obsolete GUC names to modern spellings) */ record = find_option(name, false, true, WARNING); if (record) name = record->name; /* if array is currently null, then surely nothing to delete */ if (!array) return NULL; newarray = NULL; index = 1; for (i = 1; i <= ARR_DIMS(array)[0]; i++) { Datum d; char *val; bool isnull; d = array_ref(array, 1, &i, -1 /* varlenarray */ , -1 /* TEXT's typlen */ , false /* TEXT's typbyval */ , TYPALIGN_INT /* TEXT's typalign */ , &isnull); if (isnull) continue; val = TextDatumGetCString(d); /* ignore entry if it's what we want to delete */ if (strncmp(val, name, strlen(name)) == 0 && val[strlen(name)] == '=') continue; /* else add it to the output array */ if (newarray) newarray = array_set(newarray, 1, &index, d, false, -1 /* varlenarray */ , -1 /* TEXT's typlen */ , false /* TEXT's typbyval */ , TYPALIGN_INT /* TEXT's typalign */ ); else newarray = construct_array_builtin(&d, 1, TEXTOID); index++; } return newarray; } /* * Given a GUC array, delete all settings from it that our permission * level allows: if superuser, delete them all; if regular user, only * those that are PGC_USERSET or we have permission to set */ ArrayType * GUCArrayReset(ArrayType *array) { ArrayType *newarray; int i; int index; /* if array is currently null, nothing to do */ if (!array) return NULL; /* if we're superuser, we can delete everything, so just do it */ if (superuser()) return NULL; newarray = NULL; index = 1; for (i = 1; i <= ARR_DIMS(array)[0]; i++) { Datum d; char *val; char *eqsgn; bool isnull; d = array_ref(array, 1, &i, -1 /* varlenarray */ , -1 /* TEXT's typlen */ , false /* TEXT's typbyval */ , TYPALIGN_INT /* TEXT's typalign */ , &isnull); if (isnull) continue; val = TextDatumGetCString(d); eqsgn = strchr(val, '='); *eqsgn = '\0'; /* skip if we have permission to delete it */ if (validate_option_array_item(val, NULL, true)) continue; /* else add it to the output array */ if (newarray) newarray = array_set(newarray, 1, &index, d, false, -1 /* varlenarray */ , -1 /* TEXT's typlen */ , false /* TEXT's typbyval */ , TYPALIGN_INT /* TEXT's typalign */ ); else newarray = construct_array_builtin(&d, 1, TEXTOID); index++; pfree(val); } return newarray; } /* * Validate a proposed option setting for GUCArrayAdd/Delete/Reset. * * name is the option name. value is the proposed value for the Add case, * or NULL for the Delete/Reset cases. If skipIfNoPermissions is true, it's * not an error to have no permissions to set the option. * * Returns true if OK, false if skipIfNoPermissions is true and user does not * have permission to change this option (all other error cases result in an * error being thrown). */ static bool validate_option_array_item(const char *name, const char *value, bool skipIfNoPermissions) { struct config_generic *gconf; /* * There are three cases to consider: * * name is a known GUC variable. Check the value normally, check * permissions normally (i.e., allow if variable is USERSET, or if it's * SUSET and user is superuser or holds ACL_SET permissions). * * name is not known, but exists or can be created as a placeholder (i.e., * it has a valid custom name). We allow this case if you're a superuser, * otherwise not. Superusers are assumed to know what they're doing. We * can't allow it for other users, because when the placeholder is * resolved it might turn out to be a SUSET variable. (With currently * available infrastructure, we can actually handle such cases within the * current session --- but once an entry is made in pg_db_role_setting, * it's assumed to be fully validated.) * * name is not known and can't be created as a placeholder. Throw error, * unless skipIfNoPermissions is true, in which case return false. */ gconf = find_option(name, true, skipIfNoPermissions, ERROR); if (!gconf) { /* not known, failed to make a placeholder */ return false; } if (gconf->flags & GUC_CUSTOM_PLACEHOLDER) { /* * We cannot do any meaningful check on the value, so only permissions * are useful to check. */ if (superuser() || pg_parameter_aclcheck(name, GetUserId(), ACL_SET) == ACLCHECK_OK) return true; if (skipIfNoPermissions) return false; ereport(ERROR, (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE), errmsg("permission denied to set parameter \"%s\"", name))); } /* manual permissions check so we can avoid an error being thrown */ if (gconf->context == PGC_USERSET) /* ok */ ; else if (gconf->context == PGC_SUSET && (superuser() || pg_parameter_aclcheck(name, GetUserId(), ACL_SET) == ACLCHECK_OK)) /* ok */ ; else if (skipIfNoPermissions) return false; /* if a permissions error should be thrown, let set_config_option do it */ /* test for permissions and valid option value */ (void) set_config_option(name, value, superuser() ? PGC_SUSET : PGC_USERSET, PGC_S_TEST, GUC_ACTION_SET, false, 0, false); return true; } /* * Called by check_hooks that want to override the normal * ERRCODE_INVALID_PARAMETER_VALUE SQLSTATE for check hook failures. * * Note that GUC_check_errmsg() etc are just macros that result in a direct * assignment to the associated variables. That is ugly, but forced by the * limitations of C's macro mechanisms. */ void GUC_check_errcode(int sqlerrcode) { GUC_check_errcode_value = sqlerrcode; } /* * Convenience functions to manage calling a variable's check_hook. * These mostly take care of the protocol for letting check hooks supply * portions of the error report on failure. */ static bool call_bool_check_hook(struct config_bool *conf, bool *newval, void **extra, GucSource source, int elevel) { /* Quick success if no hook */ if (!conf->check_hook) return true; /* Reset variables that might be set by hook */ GUC_check_errcode_value = ERRCODE_INVALID_PARAMETER_VALUE; GUC_check_errmsg_string = NULL; GUC_check_errdetail_string = NULL; GUC_check_errhint_string = NULL; if (!conf->check_hook(newval, extra, source)) { ereport(elevel, (errcode(GUC_check_errcode_value), GUC_check_errmsg_string ? errmsg_internal("%s", GUC_check_errmsg_string) : errmsg("invalid value for parameter \"%s\": %d", conf->gen.name, (int) *newval), GUC_check_errdetail_string ? errdetail_internal("%s", GUC_check_errdetail_string) : 0, GUC_check_errhint_string ? errhint("%s", GUC_check_errhint_string) : 0)); /* Flush any strings created in ErrorContext */ FlushErrorState(); return false; } return true; } static bool call_int_check_hook(struct config_int *conf, int *newval, void **extra, GucSource source, int elevel) { /* Quick success if no hook */ if (!conf->check_hook) return true; /* Reset variables that might be set by hook */ GUC_check_errcode_value = ERRCODE_INVALID_PARAMETER_VALUE; GUC_check_errmsg_string = NULL; GUC_check_errdetail_string = NULL; GUC_check_errhint_string = NULL; if (!conf->check_hook(newval, extra, source)) { ereport(elevel, (errcode(GUC_check_errcode_value), GUC_check_errmsg_string ? errmsg_internal("%s", GUC_check_errmsg_string) : errmsg("invalid value for parameter \"%s\": %d", conf->gen.name, *newval), GUC_check_errdetail_string ? errdetail_internal("%s", GUC_check_errdetail_string) : 0, GUC_check_errhint_string ? errhint("%s", GUC_check_errhint_string) : 0)); /* Flush any strings created in ErrorContext */ FlushErrorState(); return false; } return true; } static bool call_real_check_hook(struct config_real *conf, double *newval, void **extra, GucSource source, int elevel) { /* Quick success if no hook */ if (!conf->check_hook) return true; /* Reset variables that might be set by hook */ GUC_check_errcode_value = ERRCODE_INVALID_PARAMETER_VALUE; GUC_check_errmsg_string = NULL; GUC_check_errdetail_string = NULL; GUC_check_errhint_string = NULL; if (!conf->check_hook(newval, extra, source)) { ereport(elevel, (errcode(GUC_check_errcode_value), GUC_check_errmsg_string ? errmsg_internal("%s", GUC_check_errmsg_string) : errmsg("invalid value for parameter \"%s\": %g", conf->gen.name, *newval), GUC_check_errdetail_string ? errdetail_internal("%s", GUC_check_errdetail_string) : 0, GUC_check_errhint_string ? errhint("%s", GUC_check_errhint_string) : 0)); /* Flush any strings created in ErrorContext */ FlushErrorState(); return false; } return true; } static bool call_string_check_hook(struct config_string *conf, char **newval, void **extra, GucSource source, int elevel) { volatile bool result = true; /* Quick success if no hook */ if (!conf->check_hook) return true; /* * If elevel is ERROR, or if the check_hook itself throws an elog * (undesirable, but not always avoidable), make sure we don't leak the * already-malloc'd newval string. */ PG_TRY(); { /* Reset variables that might be set by hook */ GUC_check_errcode_value = ERRCODE_INVALID_PARAMETER_VALUE; GUC_check_errmsg_string = NULL; GUC_check_errdetail_string = NULL; GUC_check_errhint_string = NULL; if (!conf->check_hook(newval, extra, source)) { ereport(elevel, (errcode(GUC_check_errcode_value), GUC_check_errmsg_string ? errmsg_internal("%s", GUC_check_errmsg_string) : errmsg("invalid value for parameter \"%s\": \"%s\"", conf->gen.name, *newval ? *newval : ""), GUC_check_errdetail_string ? errdetail_internal("%s", GUC_check_errdetail_string) : 0, GUC_check_errhint_string ? errhint("%s", GUC_check_errhint_string) : 0)); /* Flush any strings created in ErrorContext */ FlushErrorState(); result = false; } } PG_CATCH(); { guc_free(*newval); PG_RE_THROW(); } PG_END_TRY(); return result; } static bool call_enum_check_hook(struct config_enum *conf, int *newval, void **extra, GucSource source, int elevel) { /* Quick success if no hook */ if (!conf->check_hook) return true; /* Reset variables that might be set by hook */ GUC_check_errcode_value = ERRCODE_INVALID_PARAMETER_VALUE; GUC_check_errmsg_string = NULL; GUC_check_errdetail_string = NULL; GUC_check_errhint_string = NULL; if (!conf->check_hook(newval, extra, source)) { ereport(elevel, (errcode(GUC_check_errcode_value), GUC_check_errmsg_string ? errmsg_internal("%s", GUC_check_errmsg_string) : errmsg("invalid value for parameter \"%s\": \"%s\"", conf->gen.name, config_enum_lookup_by_value(conf, *newval)), GUC_check_errdetail_string ? errdetail_internal("%s", GUC_check_errdetail_string) : 0, GUC_check_errhint_string ? errhint("%s", GUC_check_errhint_string) : 0)); /* Flush any strings created in ErrorContext */ FlushErrorState(); return false; } return true; }