.

[gnulib.git] / lib / getdate.y

diff --git a/lib/getdate.y b/lib/getdate.y
index 6d93a57..3159c6d 100644 (file)
--- a/lib/getdate.y
+++ b/lib/getdate.y
@@ -102,12 +102,6 @@ extern struct tm   *localtime();
 static int yylex ();
 static int yyerror ();
 
-#if    !defined(lint) && !defined(SABER)
-static char RCS[] =
-       "$Header: str2date.y,v 2.1 90/09/06 08:15:06 cronan Exp $";
-#endif /* !defined(lint) && !defined(SABER) */
-
-
 #define EPOCH          1970
 #define HOUR(x)                ((time_t)(x) * 60)
 #define SECSPERDAY     (24L * 60L * 60L)
@@ -863,38 +857,56 @@ yylex()
     }
 }
 
+#define TM_YEAR_ORIGIN 1900
+
+/* Yield A - B, measured in seconds.  */
+static long
+difftm (a, b)
+     struct tm *a, *b;
+{
+  int ay = a->tm_year + (TM_YEAR_ORIGIN - 1);
+  int by = b->tm_year + (TM_YEAR_ORIGIN - 1);
+  int days = (
+             /* difference in day of year */
+             a->tm_yday - b->tm_yday
+             /* + intervening leap days */
+             +  ((ay >> 2) - (by >> 2))
+             -  (ay/100 - by/100)
+             +  ((ay/100 >> 2) - (by/100 >> 2))
+             /* + difference in years * 365 */
+             +  (long)(ay-by) * 365
+             );
+  return (60*(60*(24*days + (a->tm_hour - b->tm_hour))
+             + (a->tm_min - b->tm_min))
+         + (a->tm_sec - b->tm_sec));
+}
+
 time_t
 get_date(p, now)
     char               *p;
     struct timeb       *now;
 {
-    struct tm          *tm;
+    struct tm          *tm, gmt;
     struct timeb       ftz;
     time_t             Start;
     time_t             tod;
 
     yyInput = p;
-    if (now == NULL)
-      {
-       int tz;
-       struct tm *tmp;
-       time_t epoch = 0;
-
+    if (now == NULL) {
         now = &ftz;
        (void)time(&ftz.time);
 
-       /* Compute local timezone.  Do *not* take daylight savings
-          into account here.  */
-       tmp = localtime (&epoch);
-       tz = tmp->tm_hour * 60 + tmp->tm_min;   /* Minutes east of UTC.  */
-       if (tz > 0)
-         {
-           tz = 24 * 60 - tz;                  /* Minutes west of UTC.  */
-           if (tmp->tm_year == 70)
-             tz -= 24 * 60;                    /* Account for date line.  */
-         }
-       ftz.timezone = tz;
-      }
+       if (! (tm = gmtime (&ftz.time)))
+           return -1;
+       gmt = *tm;      /* Make a copy, in case localtime modifies *tm.  */
+
+       if (! (tm = localtime (&ftz.time)))
+           return -1;
+       
+       ftz.timezone = difftm (&gmt, tm) / 60;
+       if(tm->tm_isdst)
+           ftz.timezone += 60;
+    }
 
     tm = localtime(&now->time);
     yyYear = tm->tm_year;