1778 lines
45 KiB
C
1778 lines
45 KiB
C
/*-------------------------------------------------------------------------
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*
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* findtimezone.c
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* Functions for determining the default timezone to use.
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*
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* Portions Copyright (c) 1996-2024, PostgreSQL Global Development Group
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*
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* IDENTIFICATION
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* src/bin/initdb/findtimezone.c
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*
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*-------------------------------------------------------------------------
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*/
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#include "postgres_fe.h"
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#include <fcntl.h>
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#include <sys/stat.h>
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#include <time.h>
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#include <unistd.h>
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#include "pgtz.h"
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/* Ideally this would be in a .h file, but it hardly seems worth the trouble */
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extern const char *select_default_timezone(const char *share_path);
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#ifndef SYSTEMTZDIR
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static char tzdirpath[MAXPGPATH];
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#endif
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/*
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* Return full pathname of timezone data directory
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*
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* In this file, tzdirpath is assumed to be set up by select_default_timezone.
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*/
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static const char *
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pg_TZDIR(void)
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{
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#ifndef SYSTEMTZDIR
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/* normal case: timezone stuff is under our share dir */
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return tzdirpath;
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#else
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/* we're configured to use system's timezone database */
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return SYSTEMTZDIR;
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#endif
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}
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/*
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* Given a timezone name, open() the timezone data file. Return the
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* file descriptor if successful, -1 if not.
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*
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* This is simpler than the backend function of the same name because
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* we assume that the input string has the correct case already, so there
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* is no need for case-folding. (This is obviously true if we got the file
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* name from the filesystem to start with. The only other place it can come
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* from is the environment variable TZ, and there seems no need to allow
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* case variation in that; other programs aren't likely to.)
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*
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* If "canonname" is not NULL, then on success the canonical spelling of the
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* given name is stored there (the buffer must be > TZ_STRLEN_MAX bytes!).
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* This is redundant but kept for compatibility with the backend code.
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*/
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int
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pg_open_tzfile(const char *name, char *canonname)
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{
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char fullname[MAXPGPATH];
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if (canonname)
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strlcpy(canonname, name, TZ_STRLEN_MAX + 1);
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strlcpy(fullname, pg_TZDIR(), sizeof(fullname));
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if (strlen(fullname) + 1 + strlen(name) >= MAXPGPATH)
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return -1; /* not gonna fit */
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strcat(fullname, "/");
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strcat(fullname, name);
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return open(fullname, O_RDONLY | PG_BINARY, 0);
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}
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/*
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* Load a timezone definition.
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* Does not verify that the timezone is acceptable!
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*
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* This corresponds to the backend's pg_tzset(), except that we only support
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* one loaded timezone at a time.
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*/
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static pg_tz *
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pg_load_tz(const char *name)
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{
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static pg_tz tz;
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if (strlen(name) > TZ_STRLEN_MAX)
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return NULL; /* not going to fit */
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/*
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* "GMT" is always sent to tzparse(); see comments for pg_tzset().
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*/
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if (strcmp(name, "GMT") == 0)
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{
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if (!tzparse(name, &tz.state, true))
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{
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/* This really, really should not happen ... */
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return NULL;
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}
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}
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else if (tzload(name, NULL, &tz.state, true) != 0)
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{
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if (name[0] == ':' || !tzparse(name, &tz.state, false))
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{
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return NULL; /* unknown timezone */
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}
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}
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strcpy(tz.TZname, name);
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return &tz;
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}
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/*
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* The following block of code attempts to determine which timezone in our
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* timezone database is the best match for the active system timezone.
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*
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* On most systems, we rely on trying to match the observable behavior of
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* the C library's localtime() function. The database zone that matches
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* furthest into the past is the one to use. Often there will be several
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* zones with identical rankings (since the IANA database assigns multiple
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* names to many zones). We break ties by first checking for "preferred"
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* names (such as "UTC"), and then arbitrarily by preferring shorter, then
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* alphabetically earlier zone names. (If we did not explicitly prefer
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* "UTC", we would get the alias name "UCT" instead due to alphabetic
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* ordering.)
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*
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* Many modern systems use the IANA database, so if we can determine the
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* system's idea of which zone it is using and its behavior matches our zone
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* of the same name, we can skip the rather-expensive search through all the
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* zones in our database. This short-circuit path also ensures that we spell
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* the zone name the same way the system setting does, even in the presence
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* of multiple aliases for the same zone.
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*
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* Win32's native knowledge about timezones appears to be too incomplete
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* and too different from the IANA database for the above matching strategy
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* to be of any use. But there is just a limited number of timezones
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* available, so we can rely on a handmade mapping table instead.
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*/
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#ifndef WIN32
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#define T_DAY ((time_t) (60*60*24))
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#define T_WEEK ((time_t) (60*60*24*7))
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#define T_MONTH ((time_t) (60*60*24*31))
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#define MAX_TEST_TIMES (52*100) /* 100 years */
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struct tztry
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{
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int n_test_times;
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time_t test_times[MAX_TEST_TIMES];
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};
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static bool check_system_link_file(const char *linkname, struct tztry *tt,
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char *bestzonename);
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static void scan_available_timezones(char *tzdir, char *tzdirsub,
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struct tztry *tt,
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int *bestscore, char *bestzonename);
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/*
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* Get GMT offset from a system struct tm
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*/
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static int
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get_timezone_offset(struct tm *tm)
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{
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#if defined(HAVE_STRUCT_TM_TM_ZONE)
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return tm->tm_gmtoff;
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#elif defined(HAVE_INT_TIMEZONE)
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return -TIMEZONE_GLOBAL;
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#else
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#error No way to determine TZ? Can this happen?
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#endif
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}
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/*
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* Convenience subroutine to convert y/m/d to time_t (NOT pg_time_t)
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*/
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static time_t
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build_time_t(int year, int month, int day)
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{
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struct tm tm;
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memset(&tm, 0, sizeof(tm));
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tm.tm_mday = day;
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tm.tm_mon = month - 1;
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tm.tm_year = year - 1900;
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tm.tm_isdst = -1;
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return mktime(&tm);
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}
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/*
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* Does a system tm value match one we computed ourselves?
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*/
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static bool
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compare_tm(struct tm *s, struct pg_tm *p)
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{
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if (s->tm_sec != p->tm_sec ||
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s->tm_min != p->tm_min ||
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s->tm_hour != p->tm_hour ||
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s->tm_mday != p->tm_mday ||
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s->tm_mon != p->tm_mon ||
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s->tm_year != p->tm_year ||
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s->tm_wday != p->tm_wday ||
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s->tm_yday != p->tm_yday ||
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s->tm_isdst != p->tm_isdst)
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return false;
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return true;
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}
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/*
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* See how well a specific timezone setting matches the system behavior
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*
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* We score a timezone setting according to the number of test times it
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* matches. (The test times are ordered later-to-earlier, but this routine
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* doesn't actually know that; it just scans until the first non-match.)
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*
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* We return -1 for a completely unusable setting; this is worse than the
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* score of zero for a setting that works but matches not even the first
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* test time.
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*/
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static int
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score_timezone(const char *tzname, struct tztry *tt)
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{
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int i;
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pg_time_t pgtt;
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struct tm *systm;
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struct pg_tm *pgtm;
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char cbuf[TZ_STRLEN_MAX + 1];
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pg_tz *tz;
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/* Load timezone definition */
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tz = pg_load_tz(tzname);
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if (!tz)
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return -1; /* unrecognized zone name */
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/* Reject if leap seconds involved */
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if (!pg_tz_acceptable(tz))
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{
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#ifdef DEBUG_IDENTIFY_TIMEZONE
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fprintf(stderr, "Reject TZ \"%s\": uses leap seconds\n", tzname);
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#endif
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return -1;
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}
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/* Check for match at all the test times */
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for (i = 0; i < tt->n_test_times; i++)
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{
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pgtt = (pg_time_t) (tt->test_times[i]);
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pgtm = pg_localtime(&pgtt, tz);
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if (!pgtm)
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return -1; /* probably shouldn't happen */
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systm = localtime(&(tt->test_times[i]));
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if (!systm)
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{
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#ifdef DEBUG_IDENTIFY_TIMEZONE
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fprintf(stderr, "TZ \"%s\" scores %d: at %ld %04d-%02d-%02d %02d:%02d:%02d %s, system had no data\n",
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tzname, i, (long) pgtt,
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pgtm->tm_year + 1900, pgtm->tm_mon + 1, pgtm->tm_mday,
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pgtm->tm_hour, pgtm->tm_min, pgtm->tm_sec,
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pgtm->tm_isdst ? "dst" : "std");
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#endif
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return i;
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}
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if (!compare_tm(systm, pgtm))
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{
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#ifdef DEBUG_IDENTIFY_TIMEZONE
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fprintf(stderr, "TZ \"%s\" scores %d: at %ld %04d-%02d-%02d %02d:%02d:%02d %s versus %04d-%02d-%02d %02d:%02d:%02d %s\n",
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tzname, i, (long) pgtt,
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pgtm->tm_year + 1900, pgtm->tm_mon + 1, pgtm->tm_mday,
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pgtm->tm_hour, pgtm->tm_min, pgtm->tm_sec,
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pgtm->tm_isdst ? "dst" : "std",
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systm->tm_year + 1900, systm->tm_mon + 1, systm->tm_mday,
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systm->tm_hour, systm->tm_min, systm->tm_sec,
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systm->tm_isdst ? "dst" : "std");
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#endif
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return i;
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}
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if (systm->tm_isdst >= 0)
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{
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/* Check match of zone names, too */
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if (pgtm->tm_zone == NULL)
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return -1; /* probably shouldn't happen */
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memset(cbuf, 0, sizeof(cbuf));
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strftime(cbuf, sizeof(cbuf) - 1, "%Z", systm); /* zone abbr */
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if (strcmp(cbuf, pgtm->tm_zone) != 0)
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{
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#ifdef DEBUG_IDENTIFY_TIMEZONE
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fprintf(stderr, "TZ \"%s\" scores %d: at %ld \"%s\" versus \"%s\"\n",
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tzname, i, (long) pgtt,
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pgtm->tm_zone, cbuf);
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#endif
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return i;
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}
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}
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}
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#ifdef DEBUG_IDENTIFY_TIMEZONE
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fprintf(stderr, "TZ \"%s\" gets max score %d\n", tzname, i);
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#endif
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return i;
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}
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/*
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* Test whether given zone name is a perfect match to localtime() behavior
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*/
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static bool
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perfect_timezone_match(const char *tzname, struct tztry *tt)
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{
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return (score_timezone(tzname, tt) == tt->n_test_times);
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}
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/*
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* Try to identify a timezone name (in our terminology) that best matches the
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* observed behavior of the system localtime() function.
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*/
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static const char *
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identify_system_timezone(void)
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{
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static char resultbuf[TZ_STRLEN_MAX + 1];
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time_t tnow;
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time_t t;
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struct tztry tt;
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struct tm *tm;
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int thisyear;
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int bestscore;
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char tmptzdir[MAXPGPATH];
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int std_ofs;
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char std_zone_name[TZ_STRLEN_MAX + 1],
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dst_zone_name[TZ_STRLEN_MAX + 1];
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char cbuf[TZ_STRLEN_MAX + 1];
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/* Initialize OS timezone library */
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tzset();
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/*
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* Set up the list of dates to be probed to see how well our timezone
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* matches the system zone. We first probe January and July of the
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* current year; this serves to quickly eliminate the vast majority of the
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* TZ database entries. If those dates match, we probe every week for 100
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* years backwards from the current July. (Weekly resolution is good
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* enough to identify DST transition rules, since everybody switches on
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* Sundays.) This is sufficient to cover most of the Unix time_t range,
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* and we don't want to look further than that since many systems won't
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* have sane TZ behavior further back anyway. The further back the zone
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* matches, the better we score it. This may seem like a rather random
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* way of doing things, but experience has shown that system-supplied
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* timezone definitions are likely to have DST behavior that is right for
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* the recent past and not so accurate further back. Scoring in this way
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* allows us to recognize zones that have some commonality with the IANA
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* database, without insisting on exact match. (Note: we probe Thursdays,
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* not Sundays, to avoid triggering DST-transition bugs in localtime
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* itself.)
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*/
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tnow = time(NULL);
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tm = localtime(&tnow);
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if (!tm)
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return NULL; /* give up if localtime is broken... */
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thisyear = tm->tm_year + 1900;
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t = build_time_t(thisyear, 1, 15);
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/*
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* Round back to GMT midnight Thursday. This depends on the knowledge
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* that the time_t origin is Thu Jan 01 1970. (With a different origin
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* we'd be probing some other day of the week, but it wouldn't matter
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* anyway unless localtime() had DST-transition bugs.)
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*/
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t -= (t % T_WEEK);
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tt.n_test_times = 0;
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tt.test_times[tt.n_test_times++] = t;
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t = build_time_t(thisyear, 7, 15);
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t -= (t % T_WEEK);
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tt.test_times[tt.n_test_times++] = t;
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while (tt.n_test_times < MAX_TEST_TIMES)
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{
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t -= T_WEEK;
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tt.test_times[tt.n_test_times++] = t;
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}
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/*
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* Try to avoid the brute-force search by seeing if we can recognize the
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* system's timezone setting directly.
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*
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* Currently we just check /etc/localtime; there are other conventions for
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* this, but that seems to be the only one used on enough platforms to be
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* worth troubling over.
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*/
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if (check_system_link_file("/etc/localtime", &tt, resultbuf))
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return resultbuf;
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/* No luck, so search for the best-matching timezone file */
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strlcpy(tmptzdir, pg_TZDIR(), sizeof(tmptzdir));
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bestscore = -1;
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resultbuf[0] = '\0';
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scan_available_timezones(tmptzdir, tmptzdir + strlen(tmptzdir) + 1,
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&tt,
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&bestscore, resultbuf);
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if (bestscore > 0)
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{
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/* Ignore IANA's rather silly "Factory" zone; use GMT instead */
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if (strcmp(resultbuf, "Factory") == 0)
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return NULL;
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return resultbuf;
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}
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/*
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* Couldn't find a match in the database, so next we try constructed zone
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* names (like "PST8PDT").
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*
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* First we need to determine the names of the local standard and daylight
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* zones. The idea here is to scan forward from today until we have seen
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* both zones, if both are in use.
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*/
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memset(std_zone_name, 0, sizeof(std_zone_name));
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memset(dst_zone_name, 0, sizeof(dst_zone_name));
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std_ofs = 0;
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tnow = time(NULL);
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|
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/*
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* Round back to a GMT midnight so results don't depend on local time of
|
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* day
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*/
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tnow -= (tnow % T_DAY);
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|
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/*
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* We have to look a little further ahead than one year, in case today is
|
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* just past a DST boundary that falls earlier in the year than the next
|
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* similar boundary. Arbitrarily scan up to 14 months.
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*/
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for (t = tnow; t <= tnow + T_MONTH * 14; t += T_MONTH)
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{
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tm = localtime(&t);
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if (!tm)
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continue;
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if (tm->tm_isdst < 0)
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continue;
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if (tm->tm_isdst == 0 && std_zone_name[0] == '\0')
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{
|
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/* found STD zone */
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memset(cbuf, 0, sizeof(cbuf));
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strftime(cbuf, sizeof(cbuf) - 1, "%Z", tm); /* zone abbr */
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strcpy(std_zone_name, cbuf);
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std_ofs = get_timezone_offset(tm);
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}
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if (tm->tm_isdst > 0 && dst_zone_name[0] == '\0')
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{
|
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/* found DST zone */
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memset(cbuf, 0, sizeof(cbuf));
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strftime(cbuf, sizeof(cbuf) - 1, "%Z", tm); /* zone abbr */
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strcpy(dst_zone_name, cbuf);
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}
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/* Done if found both */
|
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if (std_zone_name[0] && dst_zone_name[0])
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break;
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}
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|
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/* We should have found a STD zone name by now... */
|
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if (std_zone_name[0] == '\0')
|
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{
|
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#ifdef DEBUG_IDENTIFY_TIMEZONE
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fprintf(stderr, "could not determine system time zone\n");
|
|
#endif
|
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return NULL; /* go to GMT */
|
|
}
|
|
|
|
/* If we found DST then try STD<ofs>DST */
|
|
if (dst_zone_name[0] != '\0')
|
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{
|
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snprintf(resultbuf, sizeof(resultbuf), "%s%d%s",
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std_zone_name, -std_ofs / 3600, dst_zone_name);
|
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if (score_timezone(resultbuf, &tt) > 0)
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return resultbuf;
|
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}
|
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|
|
/* Try just the STD timezone (works for GMT at least) */
|
|
strcpy(resultbuf, std_zone_name);
|
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if (score_timezone(resultbuf, &tt) > 0)
|
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return resultbuf;
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|
|
/* Try STD<ofs> */
|
|
snprintf(resultbuf, sizeof(resultbuf), "%s%d",
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std_zone_name, -std_ofs / 3600);
|
|
if (score_timezone(resultbuf, &tt) > 0)
|
|
return resultbuf;
|
|
|
|
/*
|
|
* Did not find the timezone. Fallback to use a GMT zone. Note that the
|
|
* IANA timezone database names the GMT-offset zones in POSIX style: plus
|
|
* is west of Greenwich. It's unfortunate that this is opposite of SQL
|
|
* conventions. Should we therefore change the names? Probably not...
|
|
*/
|
|
snprintf(resultbuf, sizeof(resultbuf), "Etc/GMT%s%d",
|
|
(-std_ofs > 0) ? "+" : "", -std_ofs / 3600);
|
|
|
|
#ifdef DEBUG_IDENTIFY_TIMEZONE
|
|
fprintf(stderr, "could not recognize system time zone, using \"%s\"\n",
|
|
resultbuf);
|
|
#endif
|
|
return resultbuf;
|
|
}
|
|
|
|
/*
|
|
* Examine a system-provided symlink file to see if it tells us the timezone.
|
|
*
|
|
* Unfortunately, there is little standardization of how the system default
|
|
* timezone is determined in the absence of a TZ environment setting.
|
|
* But a common strategy is to create a symlink at a well-known place.
|
|
* If "linkname" identifies a readable symlink, and the tail of its contents
|
|
* matches a zone name we know, and the actual behavior of localtime() agrees
|
|
* with what we think that zone means, then we may use that zone name.
|
|
*
|
|
* We insist on a perfect behavioral match, which might not happen if the
|
|
* system has a different IANA database version than we do; but in that case
|
|
* it seems best to fall back to the brute-force search.
|
|
*
|
|
* linkname is the symlink file location to probe.
|
|
*
|
|
* tt tells about the system timezone behavior we need to match.
|
|
*
|
|
* If we successfully identify a zone name, store it in *bestzonename and
|
|
* return true; else return false. bestzonename must be a buffer of length
|
|
* TZ_STRLEN_MAX + 1.
|
|
*/
|
|
static bool
|
|
check_system_link_file(const char *linkname, struct tztry *tt,
|
|
char *bestzonename)
|
|
{
|
|
#ifdef HAVE_READLINK
|
|
char link_target[MAXPGPATH];
|
|
int len;
|
|
const char *cur_name;
|
|
|
|
/*
|
|
* Try to read the symlink. If not there, not a symlink, etc etc, just
|
|
* quietly fail; the precise reason needn't concern us.
|
|
*/
|
|
len = readlink(linkname, link_target, sizeof(link_target));
|
|
if (len < 0 || len >= sizeof(link_target))
|
|
return false;
|
|
link_target[len] = '\0';
|
|
|
|
#ifdef DEBUG_IDENTIFY_TIMEZONE
|
|
fprintf(stderr, "symbolic link \"%s\" contains \"%s\"\n",
|
|
linkname, link_target);
|
|
#endif
|
|
|
|
/*
|
|
* The symlink is probably of the form "/path/to/zones/zone/name", or
|
|
* possibly it is a relative path. Nobody puts their zone DB directly in
|
|
* the root directory, so we can definitely skip the first component; but
|
|
* after that it's trial-and-error to identify which path component begins
|
|
* the zone name.
|
|
*/
|
|
cur_name = link_target;
|
|
while (*cur_name)
|
|
{
|
|
/* Advance to next segment of path */
|
|
cur_name = strchr(cur_name + 1, '/');
|
|
if (cur_name == NULL)
|
|
break;
|
|
/* If there are consecutive slashes, skip all, as the kernel would */
|
|
do
|
|
{
|
|
cur_name++;
|
|
} while (*cur_name == '/');
|
|
|
|
/*
|
|
* Test remainder of path to see if it is a matching zone name.
|
|
* Relative paths might contain ".."; we needn't bother testing if the
|
|
* first component is that. Also defend against overlength names.
|
|
*/
|
|
if (*cur_name && *cur_name != '.' &&
|
|
strlen(cur_name) <= TZ_STRLEN_MAX &&
|
|
perfect_timezone_match(cur_name, tt))
|
|
{
|
|
/* Success! */
|
|
strcpy(bestzonename, cur_name);
|
|
return true;
|
|
}
|
|
}
|
|
|
|
/* Couldn't extract a matching zone name */
|
|
return false;
|
|
#else
|
|
/* No symlinks? Forget it */
|
|
return false;
|
|
#endif
|
|
}
|
|
|
|
/*
|
|
* Given a timezone name, determine whether it should be preferred over other
|
|
* names which are equally good matches. The output is arbitrary but we will
|
|
* use 0 for "neutral" default preference; larger values are more preferred.
|
|
*/
|
|
static int
|
|
zone_name_pref(const char *zonename)
|
|
{
|
|
/*
|
|
* Prefer UTC over alternatives such as UCT. Also prefer Etc/UTC over
|
|
* Etc/UCT; but UTC is preferred to Etc/UTC.
|
|
*/
|
|
if (strcmp(zonename, "UTC") == 0)
|
|
return 50;
|
|
if (strcmp(zonename, "Etc/UTC") == 0)
|
|
return 40;
|
|
|
|
/*
|
|
* We don't want to pick "localtime" or "posixrules", unless we can find
|
|
* no other name for the prevailing zone. Those aren't real zone names.
|
|
*/
|
|
if (strcmp(zonename, "localtime") == 0 ||
|
|
strcmp(zonename, "posixrules") == 0)
|
|
return -50;
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Recursively scan the timezone database looking for the best match to
|
|
* the system timezone behavior.
|
|
*
|
|
* tzdir points to a buffer of size MAXPGPATH. On entry, it holds the
|
|
* pathname of a directory containing TZ files. We internally modify it
|
|
* to hold pathnames of sub-directories and files, but must restore it
|
|
* to its original contents before exit.
|
|
*
|
|
* tzdirsub points to the part of tzdir that represents the subfile name
|
|
* (ie, tzdir + the original directory name length, plus one for the
|
|
* first added '/').
|
|
*
|
|
* tt tells about the system timezone behavior we need to match.
|
|
*
|
|
* *bestscore and *bestzonename on entry hold the best score found so far
|
|
* and the name of the best zone. We overwrite them if we find a better
|
|
* score. bestzonename must be a buffer of length TZ_STRLEN_MAX + 1.
|
|
*/
|
|
static void
|
|
scan_available_timezones(char *tzdir, char *tzdirsub, struct tztry *tt,
|
|
int *bestscore, char *bestzonename)
|
|
{
|
|
int tzdir_orig_len = strlen(tzdir);
|
|
char **names;
|
|
char **namep;
|
|
|
|
names = pgfnames(tzdir);
|
|
if (!names)
|
|
return;
|
|
|
|
for (namep = names; *namep; namep++)
|
|
{
|
|
char *name = *namep;
|
|
struct stat statbuf;
|
|
|
|
/* Ignore . and .., plus any other "hidden" files */
|
|
if (name[0] == '.')
|
|
continue;
|
|
|
|
snprintf(tzdir + tzdir_orig_len, MAXPGPATH - tzdir_orig_len,
|
|
"/%s", name);
|
|
|
|
if (stat(tzdir, &statbuf) != 0)
|
|
{
|
|
#ifdef DEBUG_IDENTIFY_TIMEZONE
|
|
fprintf(stderr, "could not stat \"%s\": %m\n",
|
|
tzdir);
|
|
#endif
|
|
tzdir[tzdir_orig_len] = '\0';
|
|
continue;
|
|
}
|
|
|
|
if (S_ISDIR(statbuf.st_mode))
|
|
{
|
|
/* Recurse into subdirectory */
|
|
scan_available_timezones(tzdir, tzdirsub, tt,
|
|
bestscore, bestzonename);
|
|
}
|
|
else
|
|
{
|
|
/* Load and test this file */
|
|
int score = score_timezone(tzdirsub, tt);
|
|
|
|
if (score > *bestscore)
|
|
{
|
|
*bestscore = score;
|
|
strlcpy(bestzonename, tzdirsub, TZ_STRLEN_MAX + 1);
|
|
}
|
|
else if (score == *bestscore)
|
|
{
|
|
/* Consider how to break a tie */
|
|
int namepref = (zone_name_pref(tzdirsub) -
|
|
zone_name_pref(bestzonename));
|
|
|
|
if (namepref > 0 ||
|
|
(namepref == 0 &&
|
|
(strlen(tzdirsub) < strlen(bestzonename) ||
|
|
(strlen(tzdirsub) == strlen(bestzonename) &&
|
|
strcmp(tzdirsub, bestzonename) < 0))))
|
|
strlcpy(bestzonename, tzdirsub, TZ_STRLEN_MAX + 1);
|
|
}
|
|
}
|
|
|
|
/* Restore tzdir */
|
|
tzdir[tzdir_orig_len] = '\0';
|
|
}
|
|
|
|
pgfnames_cleanup(names);
|
|
}
|
|
#else /* WIN32 */
|
|
|
|
static const struct
|
|
{
|
|
const char *stdname; /* Windows name of standard timezone */
|
|
const char *dstname; /* Windows name of daylight timezone */
|
|
const char *pgtzname; /* Name of pgsql timezone to map to */
|
|
} win32_tzmap[] =
|
|
|
|
{
|
|
/*
|
|
* This list was built from the contents of the registry at
|
|
* HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Time
|
|
* Zones on Windows 7, Windows 10, and Windows Server 2019. Some recent
|
|
* additions have been made by comparing to the CLDR project's
|
|
* windowsZones.xml file.
|
|
*
|
|
* The zones have been matched to IANA timezones based on CLDR's mapping
|
|
* for "territory 001".
|
|
*/
|
|
{
|
|
/* (UTC+04:30) Kabul */
|
|
"Afghanistan Standard Time", "Afghanistan Daylight Time",
|
|
"Asia/Kabul"
|
|
},
|
|
{
|
|
/* (UTC-09:00) Alaska */
|
|
"Alaskan Standard Time", "Alaskan Daylight Time",
|
|
"America/Anchorage"
|
|
},
|
|
{
|
|
/* (UTC-10:00) Aleutian Islands */
|
|
"Aleutian Standard Time", "Aleutian Daylight Time",
|
|
"America/Adak"
|
|
},
|
|
{
|
|
/* (UTC+07:00) Barnaul, Gorno-Altaysk */
|
|
"Altai Standard Time", "Altai Daylight Time",
|
|
"Asia/Barnaul"
|
|
},
|
|
{
|
|
/* (UTC+03:00) Kuwait, Riyadh */
|
|
"Arab Standard Time", "Arab Daylight Time",
|
|
"Asia/Riyadh"
|
|
},
|
|
{
|
|
/* (UTC+04:00) Abu Dhabi, Muscat */
|
|
"Arabian Standard Time", "Arabian Daylight Time",
|
|
"Asia/Dubai"
|
|
},
|
|
{
|
|
/* (UTC+03:00) Baghdad */
|
|
"Arabic Standard Time", "Arabic Daylight Time",
|
|
"Asia/Baghdad"
|
|
},
|
|
{
|
|
/* (UTC-03:00) City of Buenos Aires */
|
|
"Argentina Standard Time", "Argentina Daylight Time",
|
|
"America/Buenos_Aires"
|
|
},
|
|
{
|
|
/* (UTC+04:00) Baku, Tbilisi, Yerevan */
|
|
"Armenian Standard Time", "Armenian Daylight Time",
|
|
"Asia/Yerevan"
|
|
},
|
|
{
|
|
/* (UTC+04:00) Astrakhan, Ulyanovsk */
|
|
"Astrakhan Standard Time", "Astrakhan Daylight Time",
|
|
"Europe/Astrakhan"
|
|
},
|
|
{
|
|
/* (UTC-04:00) Atlantic Time (Canada) */
|
|
"Atlantic Standard Time", "Atlantic Daylight Time",
|
|
"America/Halifax"
|
|
},
|
|
{
|
|
/* (UTC+09:30) Darwin */
|
|
"AUS Central Standard Time", "AUS Central Daylight Time",
|
|
"Australia/Darwin"
|
|
},
|
|
{
|
|
/* (UTC+08:45) Eucla */
|
|
"Aus Central W. Standard Time", "Aus Central W. Daylight Time",
|
|
"Australia/Eucla"
|
|
},
|
|
{
|
|
/* (UTC+10:00) Canberra, Melbourne, Sydney */
|
|
"AUS Eastern Standard Time", "AUS Eastern Daylight Time",
|
|
"Australia/Sydney"
|
|
},
|
|
{
|
|
/* (UTC+04:00) Baku */
|
|
"Azerbaijan Standard Time", "Azerbaijan Daylight Time",
|
|
"Asia/Baku"
|
|
},
|
|
{
|
|
/* (UTC-01:00) Azores */
|
|
"Azores Standard Time", "Azores Daylight Time",
|
|
"Atlantic/Azores"
|
|
},
|
|
{
|
|
/* (UTC-03:00) Salvador */
|
|
"Bahia Standard Time", "Bahia Daylight Time",
|
|
"America/Bahia"
|
|
},
|
|
{
|
|
/* (UTC+06:00) Dhaka */
|
|
"Bangladesh Standard Time", "Bangladesh Daylight Time",
|
|
"Asia/Dhaka"
|
|
},
|
|
{
|
|
/* (UTC+03:00) Minsk */
|
|
"Belarus Standard Time", "Belarus Daylight Time",
|
|
"Europe/Minsk"
|
|
},
|
|
{
|
|
/* (UTC+11:00) Bougainville Island */
|
|
"Bougainville Standard Time", "Bougainville Daylight Time",
|
|
"Pacific/Bougainville"
|
|
},
|
|
{
|
|
/* (UTC-01:00) Cabo Verde Is. */
|
|
"Cabo Verde Standard Time", "Cabo Verde Daylight Time",
|
|
"Atlantic/Cape_Verde"
|
|
},
|
|
{
|
|
/* (UTC-06:00) Saskatchewan */
|
|
"Canada Central Standard Time", "Canada Central Daylight Time",
|
|
"America/Regina"
|
|
},
|
|
{
|
|
/* (UTC-01:00) Cape Verde Is. */
|
|
"Cape Verde Standard Time", "Cape Verde Daylight Time",
|
|
"Atlantic/Cape_Verde"
|
|
},
|
|
{
|
|
/* (UTC+04:00) Yerevan */
|
|
"Caucasus Standard Time", "Caucasus Daylight Time",
|
|
"Asia/Yerevan"
|
|
},
|
|
{
|
|
/* (UTC+09:30) Adelaide */
|
|
"Cen. Australia Standard Time", "Cen. Australia Daylight Time",
|
|
"Australia/Adelaide"
|
|
},
|
|
{
|
|
/* (UTC-06:00) Central America */
|
|
"Central America Standard Time", "Central America Daylight Time",
|
|
"America/Guatemala"
|
|
},
|
|
{
|
|
/* (UTC+06:00) Astana */
|
|
"Central Asia Standard Time", "Central Asia Daylight Time",
|
|
"Asia/Almaty"
|
|
},
|
|
{
|
|
/* (UTC-04:00) Cuiaba */
|
|
"Central Brazilian Standard Time", "Central Brazilian Daylight Time",
|
|
"America/Cuiaba"
|
|
},
|
|
{
|
|
/* (UTC+01:00) Belgrade, Bratislava, Budapest, Ljubljana, Prague */
|
|
"Central Europe Standard Time", "Central Europe Daylight Time",
|
|
"Europe/Budapest"
|
|
},
|
|
{
|
|
/* (UTC+01:00) Sarajevo, Skopje, Warsaw, Zagreb */
|
|
"Central European Standard Time", "Central European Daylight Time",
|
|
"Europe/Warsaw"
|
|
},
|
|
{
|
|
/* (UTC+11:00) Solomon Is., New Caledonia */
|
|
"Central Pacific Standard Time", "Central Pacific Daylight Time",
|
|
"Pacific/Guadalcanal"
|
|
},
|
|
{
|
|
/* (UTC-06:00) Central Time (US & Canada) */
|
|
"Central Standard Time", "Central Daylight Time",
|
|
"America/Chicago"
|
|
},
|
|
{
|
|
/* (UTC-06:00) Guadalajara, Mexico City, Monterrey */
|
|
"Central Standard Time (Mexico)", "Central Daylight Time (Mexico)",
|
|
"America/Mexico_City"
|
|
},
|
|
{
|
|
/* (UTC+12:45) Chatham Islands */
|
|
"Chatham Islands Standard Time", "Chatham Islands Daylight Time",
|
|
"Pacific/Chatham"
|
|
},
|
|
{
|
|
/* (UTC+08:00) Beijing, Chongqing, Hong Kong, Urumqi */
|
|
"China Standard Time", "China Daylight Time",
|
|
"Asia/Shanghai"
|
|
},
|
|
{
|
|
/* (UTC) Coordinated Universal Time */
|
|
"Coordinated Universal Time", "Coordinated Universal Time",
|
|
"UTC"
|
|
},
|
|
{
|
|
/* (UTC-05:00) Havana */
|
|
"Cuba Standard Time", "Cuba Daylight Time",
|
|
"America/Havana"
|
|
},
|
|
{
|
|
/* (UTC-12:00) International Date Line West */
|
|
"Dateline Standard Time", "Dateline Daylight Time",
|
|
"Etc/GMT+12"
|
|
},
|
|
{
|
|
/* (UTC+03:00) Nairobi */
|
|
"E. Africa Standard Time", "E. Africa Daylight Time",
|
|
"Africa/Nairobi"
|
|
},
|
|
{
|
|
/* (UTC+10:00) Brisbane */
|
|
"E. Australia Standard Time", "E. Australia Daylight Time",
|
|
"Australia/Brisbane"
|
|
},
|
|
{
|
|
/* (UTC+02:00) Chisinau */
|
|
"E. Europe Standard Time", "E. Europe Daylight Time",
|
|
"Europe/Chisinau"
|
|
},
|
|
{
|
|
/* (UTC-03:00) Brasilia */
|
|
"E. South America Standard Time", "E. South America Daylight Time",
|
|
"America/Sao_Paulo"
|
|
},
|
|
{
|
|
/* (UTC-06:00) Easter Island */
|
|
"Easter Island Standard Time", "Easter Island Daylight Time",
|
|
"Pacific/Easter"
|
|
},
|
|
{
|
|
/* (UTC-05:00) Eastern Time (US & Canada) */
|
|
"Eastern Standard Time", "Eastern Daylight Time",
|
|
"America/New_York"
|
|
},
|
|
{
|
|
/* (UTC-05:00) Chetumal */
|
|
"Eastern Standard Time (Mexico)", "Eastern Daylight Time (Mexico)",
|
|
"America/Cancun"
|
|
},
|
|
{
|
|
/* (UTC+02:00) Cairo */
|
|
"Egypt Standard Time", "Egypt Daylight Time",
|
|
"Africa/Cairo"
|
|
},
|
|
{
|
|
/* (UTC+05:00) Ekaterinburg */
|
|
"Ekaterinburg Standard Time", "Ekaterinburg Daylight Time",
|
|
"Asia/Yekaterinburg"
|
|
},
|
|
{
|
|
/* (UTC+12:00) Fiji */
|
|
"Fiji Standard Time", "Fiji Daylight Time",
|
|
"Pacific/Fiji"
|
|
},
|
|
{
|
|
/* (UTC+02:00) Helsinki, Kyiv, Riga, Sofia, Tallinn, Vilnius */
|
|
"FLE Standard Time", "FLE Daylight Time",
|
|
"Europe/Kiev"
|
|
},
|
|
{
|
|
/* (UTC+04:00) Tbilisi */
|
|
"Georgian Standard Time", "Georgian Daylight Time",
|
|
"Asia/Tbilisi"
|
|
},
|
|
{
|
|
/* (UTC+00:00) Dublin, Edinburgh, Lisbon, London */
|
|
"GMT Standard Time", "GMT Daylight Time",
|
|
"Europe/London"
|
|
},
|
|
{
|
|
/* (UTC-03:00) Greenland */
|
|
"Greenland Standard Time", "Greenland Daylight Time",
|
|
"America/Godthab"
|
|
},
|
|
{
|
|
/*
|
|
* Windows uses this zone name in various places that lie near the
|
|
* prime meridian, but are not in the UK. However, most people
|
|
* probably think that "Greenwich" means UK civil time, or maybe even
|
|
* straight-up UTC. Atlantic/Reykjavik is a decent match for that
|
|
* interpretation because Iceland hasn't observed DST since 1968.
|
|
*/
|
|
/* (UTC+00:00) Monrovia, Reykjavik */
|
|
"Greenwich Standard Time", "Greenwich Daylight Time",
|
|
"Atlantic/Reykjavik"
|
|
},
|
|
{
|
|
/* (UTC+02:00) Athens, Bucharest */
|
|
"GTB Standard Time", "GTB Daylight Time",
|
|
"Europe/Bucharest"
|
|
},
|
|
{
|
|
/* (UTC-05:00) Haiti */
|
|
"Haiti Standard Time", "Haiti Daylight Time",
|
|
"America/Port-au-Prince"
|
|
},
|
|
{
|
|
/* (UTC-10:00) Hawaii */
|
|
"Hawaiian Standard Time", "Hawaiian Daylight Time",
|
|
"Pacific/Honolulu"
|
|
},
|
|
{
|
|
/* (UTC+05:30) Chennai, Kolkata, Mumbai, New Delhi */
|
|
"India Standard Time", "India Daylight Time",
|
|
"Asia/Calcutta"
|
|
},
|
|
{
|
|
/* (UTC+03:30) Tehran */
|
|
"Iran Standard Time", "Iran Daylight Time",
|
|
"Asia/Tehran"
|
|
},
|
|
{
|
|
/* (UTC+02:00) Jerusalem */
|
|
"Israel Standard Time", "Israel Daylight Time",
|
|
"Asia/Jerusalem"
|
|
},
|
|
{
|
|
/* (UTC+02:00) Jerusalem (old spelling of zone name) */
|
|
"Jerusalem Standard Time", "Jerusalem Daylight Time",
|
|
"Asia/Jerusalem"
|
|
},
|
|
{
|
|
/* (UTC+02:00) Amman */
|
|
"Jordan Standard Time", "Jordan Daylight Time",
|
|
"Asia/Amman"
|
|
},
|
|
{
|
|
/* (UTC+02:00) Kaliningrad */
|
|
"Kaliningrad Standard Time", "Kaliningrad Daylight Time",
|
|
"Europe/Kaliningrad"
|
|
},
|
|
{
|
|
/* (UTC+12:00) Petropavlovsk-Kamchatsky - Old */
|
|
"Kamchatka Standard Time", "Kamchatka Daylight Time",
|
|
"Asia/Kamchatka"
|
|
},
|
|
{
|
|
/* (UTC+09:00) Seoul */
|
|
"Korea Standard Time", "Korea Daylight Time",
|
|
"Asia/Seoul"
|
|
},
|
|
{
|
|
/* (UTC+02:00) Tripoli */
|
|
"Libya Standard Time", "Libya Daylight Time",
|
|
"Africa/Tripoli"
|
|
},
|
|
{
|
|
/* (UTC+14:00) Kiritimati Island */
|
|
"Line Islands Standard Time", "Line Islands Daylight Time",
|
|
"Pacific/Kiritimati"
|
|
},
|
|
{
|
|
/* (UTC+10:30) Lord Howe Island */
|
|
"Lord Howe Standard Time", "Lord Howe Daylight Time",
|
|
"Australia/Lord_Howe"
|
|
},
|
|
{
|
|
/* (UTC+11:00) Magadan */
|
|
"Magadan Standard Time", "Magadan Daylight Time",
|
|
"Asia/Magadan"
|
|
},
|
|
{
|
|
/* (UTC-03:00) Punta Arenas */
|
|
"Magallanes Standard Time", "Magallanes Daylight Time",
|
|
"America/Punta_Arenas"
|
|
},
|
|
{
|
|
/* (UTC+08:00) Kuala Lumpur, Singapore */
|
|
"Malay Peninsula Standard Time", "Malay Peninsula Daylight Time",
|
|
"Asia/Kuala_Lumpur"
|
|
},
|
|
{
|
|
/* (UTC-09:30) Marquesas Islands */
|
|
"Marquesas Standard Time", "Marquesas Daylight Time",
|
|
"Pacific/Marquesas"
|
|
},
|
|
{
|
|
/* (UTC+04:00) Port Louis */
|
|
"Mauritius Standard Time", "Mauritius Daylight Time",
|
|
"Indian/Mauritius"
|
|
},
|
|
{
|
|
/* (UTC-06:00) Guadalajara, Mexico City, Monterrey */
|
|
"Mexico Standard Time", "Mexico Daylight Time",
|
|
"America/Mexico_City"
|
|
},
|
|
{
|
|
/* (UTC-07:00) Chihuahua, La Paz, Mazatlan */
|
|
"Mexico Standard Time 2", "Mexico Daylight Time 2",
|
|
"America/Chihuahua"
|
|
},
|
|
{
|
|
/* (UTC-02:00) Mid-Atlantic - Old */
|
|
"Mid-Atlantic Standard Time", "Mid-Atlantic Daylight Time",
|
|
"Atlantic/South_Georgia"
|
|
},
|
|
{
|
|
/* (UTC+02:00) Beirut */
|
|
"Middle East Standard Time", "Middle East Daylight Time",
|
|
"Asia/Beirut"
|
|
},
|
|
{
|
|
/* (UTC-03:00) Montevideo */
|
|
"Montevideo Standard Time", "Montevideo Daylight Time",
|
|
"America/Montevideo"
|
|
},
|
|
{
|
|
/* (UTC+01:00) Casablanca */
|
|
"Morocco Standard Time", "Morocco Daylight Time",
|
|
"Africa/Casablanca"
|
|
},
|
|
{
|
|
/* (UTC-07:00) Mountain Time (US & Canada) */
|
|
"Mountain Standard Time", "Mountain Daylight Time",
|
|
"America/Denver"
|
|
},
|
|
{
|
|
/* (UTC-07:00) Chihuahua, La Paz, Mazatlan */
|
|
"Mountain Standard Time (Mexico)", "Mountain Daylight Time (Mexico)",
|
|
"America/Chihuahua"
|
|
},
|
|
{
|
|
/* (UTC+06:30) Yangon (Rangoon) */
|
|
"Myanmar Standard Time", "Myanmar Daylight Time",
|
|
"Asia/Rangoon"
|
|
},
|
|
{
|
|
/* (UTC+07:00) Novosibirsk */
|
|
"N. Central Asia Standard Time", "N. Central Asia Daylight Time",
|
|
"Asia/Novosibirsk"
|
|
},
|
|
{
|
|
/* (UTC+02:00) Windhoek */
|
|
"Namibia Standard Time", "Namibia Daylight Time",
|
|
"Africa/Windhoek"
|
|
},
|
|
{
|
|
/* (UTC+05:45) Kathmandu */
|
|
"Nepal Standard Time", "Nepal Daylight Time",
|
|
"Asia/Katmandu"
|
|
},
|
|
{
|
|
/* (UTC+12:00) Auckland, Wellington */
|
|
"New Zealand Standard Time", "New Zealand Daylight Time",
|
|
"Pacific/Auckland"
|
|
},
|
|
{
|
|
/* (UTC-03:30) Newfoundland */
|
|
"Newfoundland Standard Time", "Newfoundland Daylight Time",
|
|
"America/St_Johns"
|
|
},
|
|
{
|
|
/* (UTC+11:00) Norfolk Island */
|
|
"Norfolk Standard Time", "Norfolk Daylight Time",
|
|
"Pacific/Norfolk"
|
|
},
|
|
{
|
|
/* (UTC+08:00) Irkutsk */
|
|
"North Asia East Standard Time", "North Asia East Daylight Time",
|
|
"Asia/Irkutsk"
|
|
},
|
|
{
|
|
/* (UTC+07:00) Krasnoyarsk */
|
|
"North Asia Standard Time", "North Asia Daylight Time",
|
|
"Asia/Krasnoyarsk"
|
|
},
|
|
{
|
|
/* (UTC+09:00) Pyongyang */
|
|
"North Korea Standard Time", "North Korea Daylight Time",
|
|
"Asia/Pyongyang"
|
|
},
|
|
{
|
|
/* (UTC+07:00) Novosibirsk */
|
|
"Novosibirsk Standard Time", "Novosibirsk Daylight Time",
|
|
"Asia/Novosibirsk"
|
|
},
|
|
{
|
|
/* (UTC+06:00) Omsk */
|
|
"Omsk Standard Time", "Omsk Daylight Time",
|
|
"Asia/Omsk"
|
|
},
|
|
{
|
|
/* (UTC-04:00) Santiago */
|
|
"Pacific SA Standard Time", "Pacific SA Daylight Time",
|
|
"America/Santiago"
|
|
},
|
|
{
|
|
/* (UTC-08:00) Pacific Time (US & Canada) */
|
|
"Pacific Standard Time", "Pacific Daylight Time",
|
|
"America/Los_Angeles"
|
|
},
|
|
{
|
|
/* (UTC-08:00) Baja California */
|
|
"Pacific Standard Time (Mexico)", "Pacific Daylight Time (Mexico)",
|
|
"America/Tijuana"
|
|
},
|
|
{
|
|
/* (UTC+05:00) Islamabad, Karachi */
|
|
"Pakistan Standard Time", "Pakistan Daylight Time",
|
|
"Asia/Karachi"
|
|
},
|
|
{
|
|
/* (UTC-04:00) Asuncion */
|
|
"Paraguay Standard Time", "Paraguay Daylight Time",
|
|
"America/Asuncion"
|
|
},
|
|
{
|
|
/* (UTC+05:00) Qyzylorda */
|
|
"Qyzylorda Standard Time", "Qyzylorda Daylight Time",
|
|
"Asia/Qyzylorda"
|
|
},
|
|
{
|
|
/* (UTC+01:00) Brussels, Copenhagen, Madrid, Paris */
|
|
"Romance Standard Time", "Romance Daylight Time",
|
|
"Europe/Paris"
|
|
},
|
|
{
|
|
/* (UTC+04:00) Izhevsk, Samara */
|
|
"Russia Time Zone 3", "Russia Time Zone 3",
|
|
"Europe/Samara"
|
|
},
|
|
{
|
|
/* (UTC+11:00) Chokurdakh */
|
|
"Russia Time Zone 10", "Russia Time Zone 10",
|
|
"Asia/Srednekolymsk"
|
|
},
|
|
{
|
|
/* (UTC+12:00) Anadyr, Petropavlovsk-Kamchatsky */
|
|
"Russia Time Zone 11", "Russia Time Zone 11",
|
|
"Asia/Kamchatka"
|
|
},
|
|
{
|
|
/* (UTC+02:00) Kaliningrad */
|
|
"Russia TZ 1 Standard Time", "Russia TZ 1 Daylight Time",
|
|
"Europe/Kaliningrad"
|
|
},
|
|
{
|
|
/* (UTC+03:00) Moscow, St. Petersburg */
|
|
"Russia TZ 2 Standard Time", "Russia TZ 2 Daylight Time",
|
|
"Europe/Moscow"
|
|
},
|
|
{
|
|
/* (UTC+04:00) Izhevsk, Samara */
|
|
"Russia TZ 3 Standard Time", "Russia TZ 3 Daylight Time",
|
|
"Europe/Samara"
|
|
},
|
|
{
|
|
/* (UTC+05:00) Ekaterinburg */
|
|
"Russia TZ 4 Standard Time", "Russia TZ 4 Daylight Time",
|
|
"Asia/Yekaterinburg"
|
|
},
|
|
{
|
|
/* (UTC+06:00) Novosibirsk (RTZ 5) */
|
|
"Russia TZ 5 Standard Time", "Russia TZ 5 Daylight Time",
|
|
"Asia/Novosibirsk"
|
|
},
|
|
{
|
|
/* (UTC+07:00) Krasnoyarsk */
|
|
"Russia TZ 6 Standard Time", "Russia TZ 6 Daylight Time",
|
|
"Asia/Krasnoyarsk"
|
|
},
|
|
{
|
|
/* (UTC+08:00) Irkutsk */
|
|
"Russia TZ 7 Standard Time", "Russia TZ 7 Daylight Time",
|
|
"Asia/Irkutsk"
|
|
},
|
|
{
|
|
/* (UTC+09:00) Yakutsk */
|
|
"Russia TZ 8 Standard Time", "Russia TZ 8 Daylight Time",
|
|
"Asia/Yakutsk"
|
|
},
|
|
{
|
|
/* (UTC+10:00) Vladivostok */
|
|
"Russia TZ 9 Standard Time", "Russia TZ 9 Daylight Time",
|
|
"Asia/Vladivostok"
|
|
},
|
|
{
|
|
/* (UTC+11:00) Chokurdakh */
|
|
"Russia TZ 10 Standard Time", "Russia TZ 10 Daylight Time",
|
|
"Asia/Magadan"
|
|
},
|
|
{
|
|
/* (UTC+12:00) Anadyr, Petropavlovsk-Kamchatsky */
|
|
"Russia TZ 11 Standard Time", "Russia TZ 11 Daylight Time",
|
|
"Asia/Anadyr"
|
|
},
|
|
{
|
|
/* (UTC+03:00) Moscow, St. Petersburg */
|
|
"Russian Standard Time", "Russian Daylight Time",
|
|
"Europe/Moscow"
|
|
},
|
|
{
|
|
/* (UTC-03:00) Cayenne, Fortaleza */
|
|
"SA Eastern Standard Time", "SA Eastern Daylight Time",
|
|
"America/Cayenne"
|
|
},
|
|
{
|
|
/* (UTC-05:00) Bogota, Lima, Quito, Rio Branco */
|
|
"SA Pacific Standard Time", "SA Pacific Daylight Time",
|
|
"America/Bogota"
|
|
},
|
|
{
|
|
/* (UTC-04:00) Georgetown, La Paz, Manaus, San Juan */
|
|
"SA Western Standard Time", "SA Western Daylight Time",
|
|
"America/La_Paz"
|
|
},
|
|
{
|
|
/* (UTC-03:00) Saint Pierre and Miquelon */
|
|
"Saint Pierre Standard Time", "Saint Pierre Daylight Time",
|
|
"America/Miquelon"
|
|
},
|
|
{
|
|
/* (UTC+11:00) Sakhalin */
|
|
"Sakhalin Standard Time", "Sakhalin Daylight Time",
|
|
"Asia/Sakhalin"
|
|
},
|
|
{
|
|
/* (UTC+13:00) Samoa */
|
|
"Samoa Standard Time", "Samoa Daylight Time",
|
|
"Pacific/Apia"
|
|
},
|
|
{
|
|
/* (UTC+00:00) Sao Tome */
|
|
"Sao Tome Standard Time", "Sao Tome Daylight Time",
|
|
"Africa/Sao_Tome"
|
|
},
|
|
{
|
|
/* (UTC+04:00) Saratov */
|
|
"Saratov Standard Time", "Saratov Daylight Time",
|
|
"Europe/Saratov"
|
|
},
|
|
{
|
|
/* (UTC+07:00) Bangkok, Hanoi, Jakarta */
|
|
"SE Asia Standard Time", "SE Asia Daylight Time",
|
|
"Asia/Bangkok"
|
|
},
|
|
{
|
|
/* (UTC+08:00) Kuala Lumpur, Singapore */
|
|
"Singapore Standard Time", "Singapore Daylight Time",
|
|
"Asia/Singapore"
|
|
},
|
|
{
|
|
/* (UTC+02:00) Harare, Pretoria */
|
|
"South Africa Standard Time", "South Africa Daylight Time",
|
|
"Africa/Johannesburg"
|
|
},
|
|
{
|
|
/* (UTC+02:00) Juba */
|
|
"South Sudan Standard Time", "South Sudan Daylight Time",
|
|
"Africa/Juba"
|
|
},
|
|
{
|
|
/* (UTC+05:30) Sri Jayawardenepura */
|
|
"Sri Lanka Standard Time", "Sri Lanka Daylight Time",
|
|
"Asia/Colombo"
|
|
},
|
|
{
|
|
/* (UTC+02:00) Khartoum */
|
|
"Sudan Standard Time", "Sudan Daylight Time",
|
|
"Africa/Khartoum"
|
|
},
|
|
{
|
|
/* (UTC+02:00) Damascus */
|
|
"Syria Standard Time", "Syria Daylight Time",
|
|
"Asia/Damascus"
|
|
},
|
|
{
|
|
/* (UTC+08:00) Taipei */
|
|
"Taipei Standard Time", "Taipei Daylight Time",
|
|
"Asia/Taipei"
|
|
},
|
|
{
|
|
/* (UTC+10:00) Hobart */
|
|
"Tasmania Standard Time", "Tasmania Daylight Time",
|
|
"Australia/Hobart"
|
|
},
|
|
{
|
|
/* (UTC-03:00) Araguaina */
|
|
"Tocantins Standard Time", "Tocantins Daylight Time",
|
|
"America/Araguaina"
|
|
},
|
|
{
|
|
/* (UTC+09:00) Osaka, Sapporo, Tokyo */
|
|
"Tokyo Standard Time", "Tokyo Daylight Time",
|
|
"Asia/Tokyo"
|
|
},
|
|
{
|
|
/* (UTC+07:00) Tomsk */
|
|
"Tomsk Standard Time", "Tomsk Daylight Time",
|
|
"Asia/Tomsk"
|
|
},
|
|
{
|
|
/* (UTC+13:00) Nuku'alofa */
|
|
"Tonga Standard Time", "Tonga Daylight Time",
|
|
"Pacific/Tongatapu"
|
|
},
|
|
{
|
|
/* (UTC+09:00) Chita */
|
|
"Transbaikal Standard Time", "Transbaikal Daylight Time",
|
|
"Asia/Chita"
|
|
},
|
|
{
|
|
/* (UTC+03:00) Istanbul */
|
|
"Turkey Standard Time", "Turkey Daylight Time",
|
|
"Europe/Istanbul"
|
|
},
|
|
{
|
|
/* (UTC-05:00) Turks and Caicos */
|
|
"Turks And Caicos Standard Time", "Turks And Caicos Daylight Time",
|
|
"America/Grand_Turk"
|
|
},
|
|
{
|
|
/* (UTC+08:00) Ulaanbaatar */
|
|
"Ulaanbaatar Standard Time", "Ulaanbaatar Daylight Time",
|
|
"Asia/Ulaanbaatar"
|
|
},
|
|
{
|
|
/* (UTC-05:00) Indiana (East) */
|
|
"US Eastern Standard Time", "US Eastern Daylight Time",
|
|
"America/Indianapolis"
|
|
},
|
|
{
|
|
/* (UTC-07:00) Arizona */
|
|
"US Mountain Standard Time", "US Mountain Daylight Time",
|
|
"America/Phoenix"
|
|
},
|
|
{
|
|
/* (UTC) Coordinated Universal Time */
|
|
"UTC", "UTC",
|
|
"UTC"
|
|
},
|
|
{
|
|
/* (UTC+12:00) Coordinated Universal Time+12 */
|
|
"UTC+12", "UTC+12",
|
|
"Etc/GMT-12"
|
|
},
|
|
{
|
|
/* (UTC+13:00) Coordinated Universal Time+13 */
|
|
"UTC+13", "UTC+13",
|
|
"Etc/GMT-13"
|
|
},
|
|
{
|
|
/* (UTC-02:00) Coordinated Universal Time-02 */
|
|
"UTC-02", "UTC-02",
|
|
"Etc/GMT+2"
|
|
},
|
|
{
|
|
/* (UTC-08:00) Coordinated Universal Time-08 */
|
|
"UTC-08", "UTC-08",
|
|
"Etc/GMT+8"
|
|
},
|
|
{
|
|
/* (UTC-09:00) Coordinated Universal Time-09 */
|
|
"UTC-09", "UTC-09",
|
|
"Etc/GMT+9"
|
|
},
|
|
{
|
|
/* (UTC-11:00) Coordinated Universal Time-11 */
|
|
"UTC-11", "UTC-11",
|
|
"Etc/GMT+11"
|
|
},
|
|
{
|
|
/* (UTC-04:00) Caracas */
|
|
"Venezuela Standard Time", "Venezuela Daylight Time",
|
|
"America/Caracas"
|
|
},
|
|
{
|
|
/* (UTC+10:00) Vladivostok */
|
|
"Vladivostok Standard Time", "Vladivostok Daylight Time",
|
|
"Asia/Vladivostok"
|
|
},
|
|
{
|
|
/* (UTC+04:00) Volgograd */
|
|
"Volgograd Standard Time", "Volgograd Daylight Time",
|
|
"Europe/Volgograd"
|
|
},
|
|
{
|
|
/* (UTC+08:00) Perth */
|
|
"W. Australia Standard Time", "W. Australia Daylight Time",
|
|
"Australia/Perth"
|
|
},
|
|
{
|
|
/* (UTC+01:00) West Central Africa */
|
|
"W. Central Africa Standard Time", "W. Central Africa Daylight Time",
|
|
"Africa/Lagos"
|
|
},
|
|
{
|
|
/* (UTC+01:00) Amsterdam, Berlin, Bern, Rome, Stockholm, Vienna */
|
|
"W. Europe Standard Time", "W. Europe Daylight Time",
|
|
"Europe/Berlin"
|
|
},
|
|
{
|
|
/* (UTC+07:00) Hovd */
|
|
"W. Mongolia Standard Time", "W. Mongolia Daylight Time",
|
|
"Asia/Hovd"
|
|
},
|
|
{
|
|
/* (UTC+05:00) Ashgabat, Tashkent */
|
|
"West Asia Standard Time", "West Asia Daylight Time",
|
|
"Asia/Tashkent"
|
|
},
|
|
{
|
|
/* (UTC+02:00) Gaza, Hebron */
|
|
"West Bank Gaza Standard Time", "West Bank Gaza Daylight Time",
|
|
"Asia/Gaza"
|
|
},
|
|
{
|
|
/* (UTC+02:00) Gaza, Hebron */
|
|
"West Bank Standard Time", "West Bank Daylight Time",
|
|
"Asia/Hebron"
|
|
},
|
|
{
|
|
/* (UTC+10:00) Guam, Port Moresby */
|
|
"West Pacific Standard Time", "West Pacific Daylight Time",
|
|
"Pacific/Port_Moresby"
|
|
},
|
|
{
|
|
/* (UTC+09:00) Yakutsk */
|
|
"Yakutsk Standard Time", "Yakutsk Daylight Time",
|
|
"Asia/Yakutsk"
|
|
},
|
|
{
|
|
/* (UTC-07:00) Yukon */
|
|
"Yukon Standard Time", "Yukon Daylight Time",
|
|
"America/Whitehorse"
|
|
},
|
|
{
|
|
NULL, NULL, NULL
|
|
}
|
|
};
|
|
|
|
static const char *
|
|
identify_system_timezone(void)
|
|
{
|
|
int i;
|
|
char tzname[128];
|
|
char localtzname[256];
|
|
time_t t = time(NULL);
|
|
struct tm *tm = localtime(&t);
|
|
HKEY rootKey;
|
|
int idx;
|
|
|
|
if (!tm)
|
|
{
|
|
#ifdef DEBUG_IDENTIFY_TIMEZONE
|
|
fprintf(stderr, "could not identify system time zone: localtime() failed\n");
|
|
#endif
|
|
return NULL; /* go to GMT */
|
|
}
|
|
|
|
memset(tzname, 0, sizeof(tzname));
|
|
strftime(tzname, sizeof(tzname) - 1, "%Z", tm);
|
|
|
|
for (i = 0; win32_tzmap[i].stdname != NULL; i++)
|
|
{
|
|
if (strcmp(tzname, win32_tzmap[i].stdname) == 0 ||
|
|
strcmp(tzname, win32_tzmap[i].dstname) == 0)
|
|
{
|
|
#ifdef DEBUG_IDENTIFY_TIMEZONE
|
|
fprintf(stderr, "TZ \"%s\" matches system time zone \"%s\"\n",
|
|
win32_tzmap[i].pgtzname, tzname);
|
|
#endif
|
|
return win32_tzmap[i].pgtzname;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Localized Windows versions return localized names for the timezone.
|
|
* Scan the registry to find the English name, and then try matching
|
|
* against our table again.
|
|
*/
|
|
memset(localtzname, 0, sizeof(localtzname));
|
|
if (RegOpenKeyEx(HKEY_LOCAL_MACHINE,
|
|
"SOFTWARE\\Microsoft\\Windows NT\\CurrentVersion\\Time Zones",
|
|
0,
|
|
KEY_READ,
|
|
&rootKey) != ERROR_SUCCESS)
|
|
{
|
|
#ifdef DEBUG_IDENTIFY_TIMEZONE
|
|
fprintf(stderr, "could not open registry key to identify system time zone: error code %lu\n",
|
|
GetLastError());
|
|
#endif
|
|
return NULL; /* go to GMT */
|
|
}
|
|
|
|
for (idx = 0;; idx++)
|
|
{
|
|
char keyname[256];
|
|
char zonename[256];
|
|
DWORD namesize;
|
|
FILETIME lastwrite;
|
|
HKEY key;
|
|
LONG r;
|
|
|
|
memset(keyname, 0, sizeof(keyname));
|
|
namesize = sizeof(keyname);
|
|
if ((r = RegEnumKeyEx(rootKey,
|
|
idx,
|
|
keyname,
|
|
&namesize,
|
|
NULL,
|
|
NULL,
|
|
NULL,
|
|
&lastwrite)) != ERROR_SUCCESS)
|
|
{
|
|
if (r == ERROR_NO_MORE_ITEMS)
|
|
break;
|
|
#ifdef DEBUG_IDENTIFY_TIMEZONE
|
|
fprintf(stderr, "could not enumerate registry subkeys to identify system time zone: %d\n",
|
|
(int) r);
|
|
#endif
|
|
break;
|
|
}
|
|
|
|
if ((r = RegOpenKeyEx(rootKey, keyname, 0, KEY_READ, &key)) != ERROR_SUCCESS)
|
|
{
|
|
#ifdef DEBUG_IDENTIFY_TIMEZONE
|
|
fprintf(stderr, "could not open registry subkey to identify system time zone: %d\n",
|
|
(int) r);
|
|
#endif
|
|
break;
|
|
}
|
|
|
|
memset(zonename, 0, sizeof(zonename));
|
|
namesize = sizeof(zonename);
|
|
if ((r = RegQueryValueEx(key, "Std", NULL, NULL, (unsigned char *) zonename, &namesize)) != ERROR_SUCCESS)
|
|
{
|
|
#ifdef DEBUG_IDENTIFY_TIMEZONE
|
|
fprintf(stderr, "could not query value for key \"std\" to identify system time zone \"%s\": %d\n",
|
|
keyname, (int) r);
|
|
#endif
|
|
RegCloseKey(key);
|
|
continue; /* Proceed to look at the next timezone */
|
|
}
|
|
if (strcmp(tzname, zonename) == 0)
|
|
{
|
|
/* Matched zone */
|
|
strcpy(localtzname, keyname);
|
|
RegCloseKey(key);
|
|
break;
|
|
}
|
|
memset(zonename, 0, sizeof(zonename));
|
|
namesize = sizeof(zonename);
|
|
if ((r = RegQueryValueEx(key, "Dlt", NULL, NULL, (unsigned char *) zonename, &namesize)) != ERROR_SUCCESS)
|
|
{
|
|
#ifdef DEBUG_IDENTIFY_TIMEZONE
|
|
fprintf(stderr, "could not query value for key \"dlt\" to identify system time zone \"%s\": %d\n",
|
|
keyname, (int) r);
|
|
#endif
|
|
RegCloseKey(key);
|
|
continue; /* Proceed to look at the next timezone */
|
|
}
|
|
if (strcmp(tzname, zonename) == 0)
|
|
{
|
|
/* Matched DST zone */
|
|
strcpy(localtzname, keyname);
|
|
RegCloseKey(key);
|
|
break;
|
|
}
|
|
|
|
RegCloseKey(key);
|
|
}
|
|
|
|
RegCloseKey(rootKey);
|
|
|
|
if (localtzname[0])
|
|
{
|
|
/* Found a localized name, so scan for that one too */
|
|
for (i = 0; win32_tzmap[i].stdname != NULL; i++)
|
|
{
|
|
if (strcmp(localtzname, win32_tzmap[i].stdname) == 0 ||
|
|
strcmp(localtzname, win32_tzmap[i].dstname) == 0)
|
|
{
|
|
#ifdef DEBUG_IDENTIFY_TIMEZONE
|
|
fprintf(stderr, "TZ \"%s\" matches localized system time zone \"%s\" (\"%s\")\n",
|
|
win32_tzmap[i].pgtzname, tzname, localtzname);
|
|
#endif
|
|
return win32_tzmap[i].pgtzname;
|
|
}
|
|
}
|
|
}
|
|
|
|
#ifdef DEBUG_IDENTIFY_TIMEZONE
|
|
fprintf(stderr, "could not find a match for system time zone \"%s\"\n",
|
|
tzname);
|
|
#endif
|
|
return NULL; /* go to GMT */
|
|
}
|
|
#endif /* WIN32 */
|
|
|
|
|
|
/*
|
|
* Return true if the given zone name is valid and is an "acceptable" zone.
|
|
*/
|
|
static bool
|
|
validate_zone(const char *tzname)
|
|
{
|
|
pg_tz *tz;
|
|
|
|
if (!tzname || !tzname[0])
|
|
return false;
|
|
|
|
tz = pg_load_tz(tzname);
|
|
if (!tz)
|
|
return false;
|
|
|
|
if (!pg_tz_acceptable(tz))
|
|
return false;
|
|
|
|
return true;
|
|
}
|
|
|
|
/*
|
|
* Identify a suitable default timezone setting based on the environment.
|
|
*
|
|
* The installation share_path must be passed in, as that is the default
|
|
* location for the timezone database directory.
|
|
*
|
|
* We first look to the TZ environment variable. If not found or not
|
|
* recognized by our own code, we see if we can identify the timezone
|
|
* from the behavior of the system timezone library. When all else fails,
|
|
* return NULL, indicating that we should default to GMT.
|
|
*/
|
|
const char *
|
|
select_default_timezone(const char *share_path)
|
|
{
|
|
const char *tzname;
|
|
|
|
/* Initialize timezone directory path, if needed */
|
|
#ifndef SYSTEMTZDIR
|
|
snprintf(tzdirpath, sizeof(tzdirpath), "%s/timezone", share_path);
|
|
#endif
|
|
|
|
/* Check TZ environment variable */
|
|
tzname = getenv("TZ");
|
|
if (validate_zone(tzname))
|
|
return tzname;
|
|
|
|
/* Nope, so try to identify the system timezone */
|
|
tzname = identify_system_timezone();
|
|
if (validate_zone(tzname))
|
|
return tzname;
|
|
|
|
return NULL;
|
|
}
|