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Back-patch fixes to work around broken mktime() in recent glibc releases.

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REL7_2_STABLE
Tom Lane 24 years ago
parent 96464fa37c
commit 407517f039
2 changed files with 94 additions and 27 deletions
Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL
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  1. 22
      src/backend/utils/adt/date.c
  2. 99
      src/backend/utils/adt/datetime.c

22
src/backend/utils/adt/date.c
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@ -8,7 +8,7 @@
*
*
* IDENTIFICATION
* $Header: /cvsroot/pgsql/src/backend/utils/adt/date.c,v 1.64.2.2 2002/08/22 05:27:41 momjian Exp $
* $Header: /cvsroot/pgsql/src/backend/utils/adt/date.c,v 1.64.2.3 2002/09/30 20:57:10 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -274,28 +274,20 @@ date_timestamptz(PG_FUNCTION_ARGS)
TimestampTz result;
struct tm tt,
*tm = &tt;
time_t utime;
j2date((dateVal + date2j(2000, 1, 1)), &(tm->tm_year), &(tm->tm_mon), &(tm->tm_mday));
j2date((dateVal + date2j(2000, 1, 1)),
&(tm->tm_year), &(tm->tm_mon), &(tm->tm_mday));
if (IS_VALID_UTIME(tm->tm_year, tm->tm_mon, tm->tm_mday))
{
#if defined(HAVE_TM_ZONE) || defined(HAVE_INT_TIMEZONE)
int tz;
tm->tm_hour = 0;
tm->tm_min = 0;
tm->tm_sec = 0;
tm->tm_isdst = -1;
tz = DetermineLocalTimeZone(tm);
tm->tm_year -= 1900;
tm->tm_mon -= 1;
utime = mktime(tm);
if (utime == -1)
elog(ERROR, "Unable to convert date to tm");
result = utime + ((date2j(1970, 1, 1) - date2j(2000, 1, 1)) * 86400.0);
#else
result = dateVal * 86400.0 + CTimeZone;
#endif
result = dateVal * 86400.0 + tz;
}
else
{

99
src/backend/utils/adt/datetime.c
Unescape View File

@ -8,7 +8,7 @@
*
*
* IDENTIFICATION
* $Header: /cvsroot/pgsql/src/backend/utils/adt/datetime.c,v 1.87.2.1 2002/02/25 16:22:48 thomas Exp $
* $Header: /cvsroot/pgsql/src/backend/utils/adt/datetime.c,v 1.87.2.2 2002/09/30 20:57:11 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -1427,13 +1427,15 @@ DecodeDateTime(char **field, int *ftype, int nf,
/* DetermineLocalTimeZone()
*
* Given a struct tm in which tm_year, tm_mon, tm_mday, tm_hour, tm_min, and
* tm_sec fields are set, attempt to determine the applicable local zone
* (ie, regular or daylight-savings time) at that time. Set the struct tm's
* tm_isdst field accordingly, and return the actual timezone offset.
*
* This subroutine exists mainly to centralize uses of mktime() and defend
* against mktime() bugs on various platforms...
* This subroutine exists to centralize uses of mktime() and defend against
* mktime() bugs/restrictions on various platforms. This should be
* the *only* call of mktime() in the backend.
*/
int
DetermineLocalTimeZone(struct tm * tm)
@ -1441,7 +1443,10 @@ DetermineLocalTimeZone(struct tm * tm)
int tz;
if (HasCTZSet)
{
tm->tm_isdst = 0; /* for lack of a better idea */
tz = CTimeZone;
}
else if (IS_VALID_UTIME(tm->tm_year, tm->tm_mon, tm->tm_mday))
{
#if defined(HAVE_TM_ZONE) || defined(HAVE_INT_TIMEZONE)
@ -1463,20 +1468,90 @@ DetermineLocalTimeZone(struct tm * tm)
/* indicate timezone unknown */
tmp->tm_isdst = -1;
mktime(tmp);
tm->tm_isdst = tmp->tm_isdst;
if (mktime(tmp) != ((time_t) -1) &&
tmp->tm_isdst >= 0)
{
/* mktime() succeeded, trust its result */
tm->tm_isdst = tmp->tm_isdst;
#if defined(HAVE_TM_ZONE)
/* tm_gmtoff is Sun/DEC-ism */
if (tmp->tm_isdst >= 0)
/* tm_gmtoff is Sun/DEC-ism */
tz = -(tmp->tm_gmtoff);
else
tz = 0; /* assume UTC if mktime failed */
#elif defined(HAVE_INT_TIMEZONE)
tz = ((tmp->tm_isdst > 0) ? (TIMEZONE_GLOBAL - 3600) : TIMEZONE_GLOBAL);
tz = ((tmp->tm_isdst > 0) ? (TIMEZONE_GLOBAL - 3600) : TIMEZONE_GLOBAL);
#endif /* HAVE_INT_TIMEZONE */
}
else
{
/*
* We have a buggy (not to say deliberately brain damaged)
* mktime(). Work around it by using localtime() instead.
*
* First, generate the time_t value corresponding to the given
* y/m/d/h/m/s taken as GMT time. This will not overflow (at
* least not for time_t taken as signed) because of the range
* check we did above.
*/
long day,
mysec,
locsec,
delta1,
delta2;
time_t mytime;
day = (date2j(tm->tm_year, tm->tm_mon, tm->tm_mday) -
date2j(1970, 1, 1));
mysec = tm->tm_sec + (tm->tm_min + (day * 24 + tm->tm_hour) * 60) * 60;
mytime = (time_t) mysec;
/*
* Use localtime to convert that time_t to broken-down time, and
* reassemble to get a representation of local time.
*/
tmp = localtime(&mytime);
day = (date2j(tmp->tm_year + 1900, tmp->tm_mon + 1, tmp->tm_mday) -
date2j(1970, 1, 1));
locsec = tmp->tm_sec + (tmp->tm_min + (day * 24 + tmp->tm_hour) * 60) * 60;
/*
* The local time offset corresponding to that GMT time is
* now computable as mysec - locsec.
*/
delta1 = mysec - locsec;
/*
* However, if that GMT time and the local time we are actually
* interested in are on opposite sides of a daylight-savings-time
* transition, then this is not the time offset we want. So,
* adjust the time_t to be what we think the GMT time corresponding
* to our target local time is, and repeat the localtime() call
* and delta calculation. We may have to do it twice before we
* have a trustworthy delta.
*
* Note: think not to put a loop here, since if we've been given
* an "impossible" local time (in the gap during a spring-forward
* transition) we'd never get out of the loop. Twice is enough
* to give the behavior we want, which is that "impossible" times
* are taken as standard time, while at a fall-back boundary
* ambiguous times are also taken as standard.
*/
mysec += delta1;
mytime = (time_t) mysec;
tmp = localtime(&mytime);
day = (date2j(tmp->tm_year + 1900, tmp->tm_mon + 1, tmp->tm_mday) -
date2j(1970, 1, 1));
locsec = tmp->tm_sec + (tmp->tm_min + (day * 24 + tmp->tm_hour) * 60) * 60;
delta2 = mysec - locsec;
if (delta2 != delta1)
{
mysec += (delta2 - delta1);
mytime = (time_t) mysec;
tmp = localtime(&mytime);
day = (date2j(tmp->tm_year + 1900, tmp->tm_mon + 1, tmp->tm_mday) -
date2j(1970, 1, 1));
locsec = tmp->tm_sec + (tmp->tm_min + (day * 24 + tmp->tm_hour) * 60) * 60;
delta2 = mysec - locsec;
}
tm->tm_isdst = tmp->tm_isdst;
tz = (int) delta2;
}
#else /* not (HAVE_TM_ZONE || HAVE_INT_TIMEZONE) */
tm->tm_isdst = 0;
tz = CTimeZone;

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