Must guard against NULL return from localtime() when probing pre-1970

dates.  Per Magnus Hagander.

diff --git a/src/timezone/pgtz.c b/src/timezone/pgtz.c
index c3b8811fda76b6288e16c2b438be67a5c12c9df7..ced1f76251091fee3f32982cecdf63cdd44dc5f4 100644 (file)
--- a/src/timezone/pgtz.c
+++ b/src/timezone/pgtz.c
@@ -6,7 +6,7 @@
  * Portions Copyright (c) 1996-2003, PostgreSQL Global Development Group
  *
  * IDENTIFICATION
- *   $PostgreSQL: pgsql/src/timezone/pgtz.c,v 1.19 2004/07/22 05:28:30 tgl Exp $
+ *   $PostgreSQL: pgsql/src/timezone/pgtz.c,v 1.20 2004/07/30 17:31:24 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -182,6 +182,15 @@ score_timezone(const char *tzname, struct tztry *tt)
        if (!pgtm)
            return -1;      /* probably shouldn't happen */
        systm = localtime(&(tt->test_times[i]));
+       if (!systm)
+       {
+           elog(DEBUG4, "TZ \"%s\" scores %d: at %ld %04d-%02d-%02d %02d:%02d:%02d %s, system had no data",
+                tzname, i, (long) pgtt,
+                pgtm->tm_year + 1900, pgtm->tm_mon + 1, pgtm->tm_mday,
+                pgtm->tm_hour, pgtm->tm_min, pgtm->tm_sec,
+                pgtm->tm_isdst ? "dst" : "std");
+           return i;
+       }
        if (!compare_tm(systm, pgtm))
        {
            elog(DEBUG4, "TZ \"%s\" scores %d: at %ld %04d-%02d-%02d %02d:%02d:%02d %s versus %04d-%02d-%02d %02d:%02d:%02d %s",
@@ -302,6 +311,8 @@ identify_system_timezone(void)
    for (t = tnow; t <= tnow + T_MONTH * 14; t += T_MONTH)
    {
        tm = localtime(&t);
+       if (!tm)
+           continue;
        if (tm->tm_isdst < 0)
            continue;
        if (tm->tm_isdst == 0 && std_zone_name[0] == '\0')
@@ -491,7 +502,7 @@ tz_acceptable(void)
     */
    time2000 = (POSTGRES_EPOCH_JDATE - UNIX_EPOCH_JDATE) * 86400;
    tt = pg_localtime(&time2000);
-   if (tt->tm_sec != 0)
+   if (!tt || tt->tm_sec != 0)
        return false;
 
    return true;