diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c index ab8b5fd8b4..db81e3bd70 100644 --- a/src/backend/access/transam/xact.c +++ b/src/backend/access/transam/xact.c @@ -10,7 +10,7 @@ * * * IDENTIFICATION - * $PostgreSQL: pgsql/src/backend/access/transam/xact.c,v 1.234 2007/02/09 03:35:33 tgl Exp $ + * $PostgreSQL: pgsql/src/backend/access/transam/xact.c,v 1.235 2007/03/12 22:09:27 petere Exp $ * *------------------------------------------------------------------------- */ @@ -1513,6 +1513,9 @@ CommitTransaction(void) /* NOTIFY commit must come before lower-level cleanup */ AtCommit_Notify(); + /* GUC processing could abort transaction */ + AtEOXact_GUC(true, false); + /* * Update flat files if we changed pg_database, pg_authid or * pg_auth_members. This should be the last step before commit. @@ -1623,7 +1626,6 @@ CommitTransaction(void) /* Check we've released all catcache entries */ AtEOXact_CatCache(true); - AtEOXact_GUC(true, false); AtEOXact_SPI(true); AtEOXact_on_commit_actions(true); AtEOXact_Namespace(true); diff --git a/src/backend/utils/misc/guc-file.l b/src/backend/utils/misc/guc-file.l index c9b6958cee..b9b62bcabf 100644 --- a/src/backend/utils/misc/guc-file.l +++ b/src/backend/utils/misc/guc-file.l @@ -4,7 +4,7 @@ * * Copyright (c) 2000-2007, PostgreSQL Global Development Group * - * $PostgreSQL: pgsql/src/backend/utils/misc/guc-file.l,v 1.47 2007/02/10 14:58:55 petere Exp $ + * $PostgreSQL: pgsql/src/backend/utils/misc/guc-file.l,v 1.48 2007/03/12 22:09:27 petere Exp $ */ %{ @@ -54,6 +54,8 @@ static bool ParseConfigFile(const char *config_file, const char *calling_file, static void free_name_value_list(struct name_value_pair * list); static char *GUC_scanstr(const char *s); +static char *custom_variable_classes_backup; + %} %option 8bit @@ -116,6 +118,10 @@ ProcessConfigFile(GucContext context) { int elevel; struct name_value_pair *item, *head, *tail; + int i; + bool *in_conffile = NULL; + const char *var; + bool success = false; Assert(context == PGC_POSTMASTER || context == PGC_SIGHUP); @@ -132,6 +138,18 @@ ProcessConfigFile(GucContext context) head = tail = NULL; + /* + * We do not know whether we will read the configuration file + * without error. If we encounter an error we have to restore the + * previous value of the custom_variable_classes variable for + * consistency. Therefore we have to save its value. + */ + var = GetConfigOption("custom_variable_classes"); + if (var) + custom_variable_classes_backup = pstrdup(var); + set_config_option("custom_variable_classes", NULL, context, + PGC_S_DEFAULT, false, true); + if (!ParseConfigFile(ConfigFileName, NULL, 0, context, elevel, &head, &tail)) @@ -140,20 +158,198 @@ ProcessConfigFile(GucContext context) /* Check if all options are valid */ for (item = head; item; item = item->next) { + char *sep = strchr(item->name, GUC_QUALIFIER_SEPARATOR); + if (sep && !is_custom_class(item->name, sep - item->name)) + { + ereport(elevel, + (errcode(ERRCODE_UNDEFINED_OBJECT), + errmsg("unrecognized configuration parameter \"%s\"", + item->name))); + goto cleanup_list; + } + if (!set_config_option(item->name, item->value, context, PGC_S_FILE, false, false)) goto cleanup_list; } - /* If we got here all the options checked out okay, so apply them. */ + + /* + * Mark all variables as not showing up in the config file. The + * allocation has to take place after ParseConfigFile() since this + * function can change num_guc_variables due to custom variables. + * It would be easier to add a new field or status bit to struct + * conf_generic, but that way we would expose internal information + * that is just needed here in the following few lines. The price + * to pay for this separation are a few more loops over the set of + * configuration options, but those are expected to be rather few + * and we only have to pay the cost at SIGHUP. We initialize + * in_conffile only here because set_config_option() makes + * guc_variables grow with custom variables. + */ + in_conffile = guc_malloc(elevel, num_guc_variables * sizeof(bool)); + if (!in_conffile) + goto cleanup_list; + for (i = 0; i < num_guc_variables; i++) + in_conffile[i] = false; + for (item = head; item; item = item->next) { - set_config_option(item->name, item->value, context, - PGC_S_FILE, false, true); + /* + * After set_config_option() the variable name item->name is + * known to exist. + */ + Assert(guc_get_index(item->name) >= 0); + in_conffile[guc_get_index(item->name)] = true; } + for (i = 0; i < num_guc_variables; i++) + { + struct config_generic *gconf = guc_variables[i]; + if (!in_conffile[i] && strchr(gconf->name, GUC_QUALIFIER_SEPARATOR)) + { + /* handle custom variables here */ + int j; + + /* + * guc_delete_variable will re-sort the array of + * configuration options and decrease num_guc_variables by + * one. + */ + guc_delete_custom_variable(gconf->name); + + /* + * Since the array is always sorted we just have to shift + * all boolean values after position i by one position to + * the left. + */ + for (j = i; j < num_guc_variables; j++) + in_conffile[j] = in_conffile[j+1]; + + /* + * Decrease the loop variable to re-test the entry at the + * current position that is now a different one. + */ + i--; + + continue; + } + else if (!in_conffile[i] && gconf->source == PGC_S_FILE) + { + if (gconf->context < PGC_SIGHUP) + ereport(elevel, + (errcode(ERRCODE_CANT_CHANGE_RUNTIME_PARAM), + errmsg("parameter \"%s\" cannot be changed after server start; configuration file change ignored", + gconf->name))); + else + { + /* prepare */ + GucStack *stack; + if (gconf->reset_source == PGC_S_FILE) + gconf->reset_source = PGC_S_DEFAULT; + for (stack = gconf->stack; stack; stack = stack->prev) + if (stack->source == PGC_S_FILE) + stack->source = PGC_S_DEFAULT; + /* apply the default */ + set_config_option(gconf->name, NULL, context, + PGC_S_DEFAULT, false, true); + } + } + else if (!in_conffile[i] && gconf->reset_source == PGC_S_FILE) + { + /*------ + * Change the reset_val to default_val. Here's an + * example: In the configuration file we have + * + * seq_page_cost = 3.00 + * + * Now we execute in a session + * + * SET seq_page_cost TO 4.00; + * + * Then we remove this option from the configuration file + * and send SIGHUP. Now when you execute + * + * RESET seq_page_cost; + * + * it should fall back to 1.00 (the default value for + * seq_page_cost) and not to 3.00 (which is the current + * reset_val). + */ + + switch (gconf->vartype) + { + case PGC_BOOL: + { + struct config_bool *conf; + conf = (struct config_bool *) gconf; + conf->reset_val = conf->boot_val; + break; + } + case PGC_INT: + { + struct config_int *conf; + conf = (struct config_int *) gconf; + conf->reset_val = conf->boot_val; + break; + } + case PGC_REAL: + { + struct config_real *conf; + conf = (struct config_real *) gconf; + conf->reset_val = conf->boot_val; + break; + } + case PGC_STRING: + { + struct config_string *conf; + conf = (struct config_string *) gconf; + /* + * We can cast away the const here because we + * won't free the address. It is protected by + * set_string_field() and string_field_used(). + */ + conf->reset_val = (char *) conf->boot_val; + break; + } + } + } + } + + /* If we got here all the options checked out okay, so apply them. */ + for (item = head; item; item = item->next) + set_config_option(item->name, item->value, context, + PGC_S_FILE, false, true); + + /* + * Reset variables to the value of environment variables + * (PGC_S_ENV_VAR overrules PGC_S_FILE). PGPORT is ignored, + * because it cannot be changed without restart. + */ + var = getenv("PGDATESTYLE"); + if (var != NULL) + set_config_option("datestyle", var, context, + PGC_S_ENV_VAR, false, true); + + var = getenv("PGCLIENTENCODING"); + if (var != NULL) + set_config_option("client_encoding", var, context, + PGC_S_ENV_VAR, false, true); + + success = true; + cleanup_list: + free(in_conffile); free_name_value_list(head); + if (!success) + set_config_option("custom_variable_classes", + custom_variable_classes_backup, + context, PGC_S_FILE, false, true); + if (custom_variable_classes_backup) + { + pfree(custom_variable_classes_backup); + custom_variable_classes_backup = NULL; + } } @@ -312,14 +508,14 @@ ParseConfigFile(const char *config_file, const char *calling_file, { pfree(opt_name); pfree(opt_value); - /* we assume error message was logged already */ + + /* We assume the error message was logged already. */ OK = false; goto cleanup_exit; } - pfree(opt_name); - pfree(opt_value); } - else + + if (pg_strcasecmp(opt_name, "include") != 0) { /* append to list */ struct name_value_pair *item; diff --git a/src/backend/utils/misc/guc.c b/src/backend/utils/misc/guc.c index 0fa3489fb6..48ac8705b1 100644 --- a/src/backend/utils/misc/guc.c +++ b/src/backend/utils/misc/guc.c @@ -10,7 +10,7 @@ * Written by Peter Eisentraut . * * IDENTIFICATION - * $PostgreSQL: pgsql/src/backend/utils/misc/guc.c,v 1.379 2007/03/06 02:06:14 momjian Exp $ + * $PostgreSQL: pgsql/src/backend/utils/misc/guc.c,v 1.380 2007/03/12 22:09:28 petere Exp $ * *-------------------------------------------------------------------- */ @@ -2439,7 +2439,8 @@ set_string_field(struct config_string * conf, char **field, char *newval) if (oldval == NULL || oldval == *(conf->variable) || oldval == conf->reset_val || - oldval == conf->tentative_val) + oldval == conf->tentative_val || + oldval == conf->boot_val) return; for (stack = conf->gen.stack; stack; stack = stack->prev) { @@ -2462,7 +2463,8 @@ string_field_used(struct config_string * conf, char *strval) if (strval == *(conf->variable) || strval == conf->reset_val || - strval == conf->tentative_val) + strval == conf->tentative_val || + strval == conf->boot_val) return true; for (stack = conf->gen.stack; stack; stack = stack->prev) { @@ -2631,6 +2633,105 @@ add_guc_variable(struct config_generic * var, int elevel) return true; } +static int +guc_get_index(const char *name) +{ + int i; + + for (i = 0; i < num_guc_variables; i++) + if (strcasecmp(name, guc_variables[i]->name) == 0) + return i; + + return -1; +} + +static void +guc_delete_variable(const char *name) +{ + struct config_generic *gen; + int idx; + GucStack *stack, *prev; + struct config_string *conf; + + idx = guc_get_index(name); + Assert(idx >= 0); + + gen = guc_variables[idx]; + + /* + * Even though this function could delete other types of variables as well, + * at the moment we only call it for custom variables that always have type + * string. + */ + Assert(gen->group == CUSTOM_OPTIONS); + Assert(gen->vartype == PGC_STRING); + + conf = (struct config_string *) gen; + set_string_field(conf, &conf->reset_val, NULL); + set_string_field(conf, &conf->tentative_val, NULL); + for (stack = conf->gen.stack; stack; stack = prev) + { + set_string_field(conf, &stack->tentative_val.stringval, NULL); + set_string_field(conf, &stack->value.stringval, NULL); + prev = stack->prev; + pfree(stack); + } + + /* no pfree() here, gen has been allocated via guc_malloc */ + free(gen); + guc_variables[idx] = guc_variables[num_guc_variables - 1]; + num_guc_variables--; + qsort((void *) guc_variables, num_guc_variables, + sizeof(struct config_generic *), guc_var_compare); +} + +static void +guc_delete_custom_variable(const char *name) +{ + struct config_generic *gen; + struct config_string *conf; + int idx; + + idx = guc_get_index(name); + Assert(idx >= 0); + + gen = guc_variables[idx]; + + Assert(gen->group == CUSTOM_OPTIONS); + Assert(gen->vartype == PGC_STRING); + + conf = (struct config_string *) gen; + + /* + * Here we check whether it is safe to really delete the variable + * or if we have to wait for the end of the transaction. We do + * not remove the physical entry of a custom variable if it has + * been SET to another value in the transaction but has been + * removed from the configuration file. + */ + if (gen->stack) + { + /* + * Make sure this custom variable (which has a definition in + * the configuration file) behaves as any other custom + * variable from now on. We have deleted its former + * definition; that's why "RESET foo.bar" should not fall back + * to this deleted definition from the configuration file. + * The analogy is that any other custom variable that gets + * introduced in a session has no reset value either. And a + * variable that has been SET within a transaction and has + * then been deleted from the configuration file should behave + * as if it had been introduced in the session. + */ + Assert(gen->vartype == PGC_STRING); + gen->reset_source = PGC_S_DEFAULT; + set_string_field(conf, &conf->reset_val, NULL); + } + else + guc_delete_variable(name); +} + + /* * Create and add a placeholder variable. It's presumed to belong * to a valid custom variable class at this point. @@ -2809,39 +2910,39 @@ InitializeGUCOptions(void) struct config_bool *conf = (struct config_bool *) gconf; if (conf->assign_hook) - if (!(*conf->assign_hook) (conf->reset_val, true, + if (!(*conf->assign_hook) (conf->boot_val, true, PGC_S_DEFAULT)) elog(FATAL, "failed to initialize %s to %d", - conf->gen.name, (int) conf->reset_val); - *conf->variable = conf->reset_val; + conf->gen.name, (int) conf->boot_val); + *conf->variable = conf->reset_val = conf->boot_val; break; } case PGC_INT: { struct config_int *conf = (struct config_int *) gconf; - Assert(conf->reset_val >= conf->min); - Assert(conf->reset_val <= conf->max); + Assert(conf->boot_val >= conf->min); + Assert(conf->boot_val <= conf->max); if (conf->assign_hook) - if (!(*conf->assign_hook) (conf->reset_val, true, + if (!(*conf->assign_hook) (conf->boot_val, true, PGC_S_DEFAULT)) elog(FATAL, "failed to initialize %s to %d", - conf->gen.name, conf->reset_val); - *conf->variable = conf->reset_val; + conf->gen.name, conf->boot_val); + *conf->variable = conf->reset_val = conf->boot_val; break; } case PGC_REAL: { struct config_real *conf = (struct config_real *) gconf; - Assert(conf->reset_val >= conf->min); - Assert(conf->reset_val <= conf->max); + Assert(conf->boot_val >= conf->min); + Assert(conf->boot_val <= conf->max); if (conf->assign_hook) - if (!(*conf->assign_hook) (conf->reset_val, true, + if (!(*conf->assign_hook) (conf->boot_val, true, PGC_S_DEFAULT)) elog(FATAL, "failed to initialize %s to %g", - conf->gen.name, conf->reset_val); - *conf->variable = conf->reset_val; + conf->gen.name, conf->boot_val); + *conf->variable = conf->reset_val = conf->boot_val; break; } case PGC_STRING: @@ -3296,8 +3397,25 @@ push_old_value(struct config_generic * gconf) } } -/* +/*------ * Do GUC processing at transaction or subtransaction commit or abort. + * + * GUC can abort the transaction in exactly one case, namely when you + * delete a custom variable class while a still-open transaction has + * SET a custom variable within this class. + * + * Consider the following example. In the configuration file we could + * have: + * + * custom_variable_classes = "foo" + * + * begin; + * set foo.bar to 1; + * + * commit; + * + * This will result in an error because foo.bar is no longer available + * but commit would have to guarantee that the value is preserved. */ void AtEOXact_GUC(bool isCommit, bool isSubXact) @@ -3335,6 +3453,33 @@ AtEOXact_GUC(bool isCommit, bool isSubXact) continue; Assert(stack->nest_level == my_level); + if (!isSubXact && gconf->group == CUSTOM_OPTIONS) + { + char *dot = strchr(gconf->name, GUC_QUALIFIER_SEPARATOR); + Assert(dot != NULL); + if (!is_custom_class(gconf->name, dot - gconf->name)) + { + if (!isCommit) + { + /* We do not commit the transaction. Delete the variable. */ + guc_delete_variable(gconf->name); + /* Call the loop with the same i again, which is + * the next variable. */ + i--; + continue; + } + else + { + /* We commit the transaction. Throw an error that + * the respective custom class does not exist. */ + ereport(ERROR, + (errcode(ERRCODE_UNDEFINED_OBJECT), + errmsg("no valid custom variable class available for " + "parameter \"%s\"", gconf->name))); + } + } + } + /* * We will pop the stack entry. Start by restoring outer xact status * (since we may want to modify it below). Be careful to use @@ -3998,19 +4143,26 @@ set_config_option(const char *name, const char *value, } /* - * Should we set reset/stacked values? (If so, the behavior is not - * transactional.) + * 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); + 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. + * 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. There's one exception to + * this rule: if we want to apply the default value to variables + * that were removed from the configuration file. This is + * indicated by source == PGC_S_DEFAULT. */ - if (record->source > source) + if (record->source > source && source != PGC_S_DEFAULT) { if (changeVal && !makeDefault) { @@ -4042,6 +4194,14 @@ set_config_option(const char *name, const char *value, return false; } } + /* + * If value == NULL and source == PGC_S_DEFAULT then + * we reset some value to its default (removed from + * configuration file). + */ + else if (source == PGC_S_DEFAULT) + newval = conf->boot_val; + /* else we handle a "RESET varname" command */ else { newval = conf->reset_val; @@ -4126,6 +4286,14 @@ set_config_option(const char *name, const char *value, return false; } } + /* + * If value == NULL and source == PGC_S_DEFAULT then + * we reset some value to its default (removed from + * configuration file). + */ + else if (source == PGC_S_DEFAULT) + newval = conf->boot_val; + /* else we handle a "RESET varname" command */ else { newval = conf->reset_val; @@ -4210,6 +4378,14 @@ set_config_option(const char *name, const char *value, return false; } } + /* + * If value == NULL and source == PGC_S_DEFAULT then + * we reset some value to its default (removed from + * configuration file). + */ + else if (source == PGC_S_DEFAULT) + newval = conf->boot_val; + /* else we handle a "RESET varname" command */ else { newval = conf->reset_val; @@ -4288,6 +4464,23 @@ set_config_option(const char *name, const char *value, if (conf->gen.flags & GUC_IS_NAME) truncate_identifier(newval, strlen(newval), true); } + /* + * If value == NULL and source == PGC_S_DEFAULT then + * we reset some value to its default (removed from + * configuration file). + */ + else if (source == PGC_S_DEFAULT) + { + if (conf->boot_val == NULL) + newval = NULL; + else + { + newval = guc_strdup(elevel, conf->boot_val); + if (newval == NULL) + return false; + } + } + /* else we handle a "RESET varname" command */ else if (conf->reset_val) { /* @@ -6304,6 +6497,13 @@ assign_custom_variable_classes(const char *newval, bool doit, GucSource source) int c; StringInfoData buf; + /* + * Resetting custom_variable_classes by removing it from the + * configuration file will lead to newval = NULL + */ + if (newval == NULL) + return guc_strdup(ERROR, ""); + initStringInfo(&buf); while ((c = *cp++) != 0) { @@ -6348,7 +6548,7 @@ assign_custom_variable_classes(const char *newval, bool doit, GucSource source) if (buf.len == 0) newval = NULL; else if (doit) - newval = strdup(buf.data); + newval = guc_strdup(ERROR, buf.data); pfree(buf.data); return newval; diff --git a/src/include/utils/guc_tables.h b/src/include/utils/guc_tables.h index 1b89024eeb..19dd16d15e 100644 --- a/src/include/utils/guc_tables.h +++ b/src/include/utils/guc_tables.h @@ -7,7 +7,7 @@ * * Portions Copyright (c) 1996-2007, PostgreSQL Global Development Group * - * $PostgreSQL: pgsql/src/include/utils/guc_tables.h,v 1.30 2007/01/05 22:19:59 momjian Exp $ + * $PostgreSQL: pgsql/src/include/utils/guc_tables.h,v 1.31 2007/03/12 22:09:28 petere Exp $ * *------------------------------------------------------------------------- */ @@ -154,11 +154,12 @@ struct config_bool /* these fields must be set correctly in initial value: */ /* (all but reset_val are constants) */ bool *variable; - bool reset_val; + bool boot_val; GucBoolAssignHook assign_hook; GucShowHook show_hook; /* variable fields, initialized at runtime: */ bool tentative_val; + bool reset_val; }; struct config_int @@ -167,13 +168,14 @@ struct config_int /* these fields must be set correctly in initial value: */ /* (all but reset_val are constants) */ int *variable; - int reset_val; + int boot_val; int min; int max; GucIntAssignHook assign_hook; GucShowHook show_hook; /* variable fields, initialized at runtime: */ int tentative_val; + int reset_val; }; struct config_real @@ -182,13 +184,14 @@ struct config_real /* these fields must be set correctly in initial value: */ /* (all but reset_val are constants) */ double *variable; - double reset_val; + double boot_val; double min; double max; GucRealAssignHook assign_hook; GucShowHook show_hook; /* variable fields, initialized at runtime: */ double tentative_val; + double reset_val; }; struct config_string