diff options
Diffstat (limited to 'src/timezone/pgtz.c')
| -rw-r--r-- | src/timezone/pgtz.c | 63 |
1 files changed, 46 insertions, 17 deletions
diff --git a/src/timezone/pgtz.c b/src/timezone/pgtz.c index b29a781cf8..ce6e7d1add 100644 --- a/src/timezone/pgtz.c +++ b/src/timezone/pgtz.c @@ -3,10 +3,10 @@ * pgtz.c * Timezone Library Integration Functions * - * Portions Copyright (c) 1996-2010, PostgreSQL Global Development Group + * Portions Copyright (c) 1996-2011, PostgreSQL Global Development Group * * IDENTIFICATION - * $PostgreSQL: pgsql/src/timezone/pgtz.c,v 1.74 2010/07/06 19:19:01 momjian Exp $ + * src/timezone/pgtz.c * *------------------------------------------------------------------------- */ @@ -1158,7 +1158,7 @@ identify_system_timezone(void) memset(zonename, 0, sizeof(zonename)); namesize = sizeof(zonename); - if ((r = RegQueryValueEx(key, "Std", NULL, NULL, zonename, &namesize)) != ERROR_SUCCESS) + if ((r = RegQueryValueEx(key, "Std", NULL, NULL, (unsigned char *) zonename, &namesize)) != ERROR_SUCCESS) { ereport(LOG, (errmsg_internal("could not query value for key \"std\" to identify system time zone \"%s\": %i", @@ -1175,7 +1175,7 @@ identify_system_timezone(void) } memset(zonename, 0, sizeof(zonename)); namesize = sizeof(zonename); - if ((r = RegQueryValueEx(key, "Dlt", NULL, NULL, zonename, &namesize)) != ERROR_SUCCESS) + if ((r = RegQueryValueEx(key, "Dlt", NULL, NULL, (unsigned char *) zonename, &namesize)) != ERROR_SUCCESS) { ereport(LOG, (errmsg_internal("could not query value for key \"dlt\" to identify system time zone \"%s\": %i", @@ -1438,34 +1438,63 @@ pg_timezone_pre_initialize(void) * This is called after initial loading of postgresql.conf. If no TimeZone * setting was found therein, we try to derive one from the environment. * Likewise for log_timezone. + * + * Note: this is also called from ProcessConfigFile, to re-establish valid + * GUC settings if the GUCs have been reset to default following their + * removal from postgresql.conf. */ void pg_timezone_initialize(void) { pg_tz *def_tz = NULL; - /* Do we need to try to figure the session timezone? */ - if (pg_strcasecmp(GetConfigOption("timezone", false), "UNKNOWN") == 0) + /* + * Make sure that session_timezone and log_timezone are set. + * (session_timezone could still be NULL even if a timezone value was set + * in postgresql.conf, if that setting was interval-based rather than + * timezone-based.) + */ + if (!session_timezone) { - /* Select setting */ def_tz = select_default_timezone(); session_timezone = def_tz; - /* Tell GUC about the value. Will redundantly call pg_tzset() */ - SetConfigOption("timezone", pg_get_timezone_name(def_tz), - PGC_POSTMASTER, PGC_S_ARGV); } - - /* What about the log timezone? */ - if (pg_strcasecmp(GetConfigOption("log_timezone", false), "UNKNOWN") == 0) + if (!log_timezone) { - /* Select setting, but don't duplicate work */ + /* Don't duplicate work */ if (!def_tz) def_tz = select_default_timezone(); log_timezone = def_tz; - /* Tell GUC about the value. Will redundantly call pg_tzset() */ - SetConfigOption("log_timezone", pg_get_timezone_name(def_tz), - PGC_POSTMASTER, PGC_S_ARGV); } + + /* + * Now, set the timezone and log_timezone GUCs if they're still default. + * (This will redundantly call pg_tzset().) + * + * We choose to label these values PGC_S_ENV_VAR, rather than + * PGC_S_DYNAMIC_DEFAULT which would be functionally equivalent, because + * they came either from getenv("TZ") or from libc behavior that's + * determined by process environment of some kind. + * + * Note: in the case where a setting has just been removed from + * postgresql.conf, this code will not do what you might expect, namely + * call select_default_timezone() and install that value as the setting. + * Rather, the previously active setting --- typically the one from + * postgresql.conf --- will be reinstalled, relabeled as PGC_S_ENV_VAR. If + * we did try to install the "correct" default value, the effect would be + * that each postmaster child would independently run an extremely + * expensive search of the timezone database, bringing the database to its + * knees for possibly multiple seconds. This is so unpleasant, and could + * so easily be triggered quite unintentionally, that it seems better to + * violate the principle of least astonishment. + */ + if (GetConfigOptionResetString("timezone") == NULL) + SetConfigOption("timezone", pg_get_timezone_name(session_timezone), + PGC_POSTMASTER, PGC_S_ENV_VAR); + + if (GetConfigOptionResetString("log_timezone") == NULL) + SetConfigOption("log_timezone", pg_get_timezone_name(log_timezone), + PGC_POSTMASTER, PGC_S_ENV_VAR); } |