[project @ 1999-05-11 17:05:43 by keithw]

[ghc-hetmet.git] / ghc / lib / std / cbits / toLocalTime.c

diff --git a/ghc/lib/std/cbits/toLocalTime.c b/ghc/lib/std/cbits/toLocalTime.c
index 6e775b7..1304805 100644 (file)
--- a/ghc/lib/std/cbits/toLocalTime.c
+++ b/ghc/lib/std/cbits/toLocalTime.c
@@ -1,7 +1,7 @@
 /* 
  * (c) The GRASP/AQUA Project, Glasgow University, 1994-1998
  *
- * $Id: toLocalTime.c,v 1.1 1998/04/10 10:54:58 simonm Exp $
+ * $Id: toLocalTime.c,v 1.3 1998/12/02 13:28:02 simonm Exp $
  *
  * toCalendarTime Runtime Support
  */
@@ -65,3 +65,48 @@ toLocalTime(I_ size, StgByteArray d, StgByteArray res)
 
     return (StgAddr)res;
 }
+
+/* Note that we DO NOT return res as a result.
+ * res is typically a MutableByteArray and it seems very dubious
+ * to return a pointer into the middle of it.
+ */
+StgInt prim_toLocalTime ( StgInt64 d, StgByteArray res)
+{
+    struct tm *tm,*tmp=(struct tm *)res;
+    time_t t = (time_t) d;
+
+    if (t < 0) 
+        return 0;
+
+    tm = localtime(&t);
+    
+    if (tm == NULL)
+       return 0;
+
+    /*
+      localtime() may return a ptr to statically allocated storage,
+      so to make toLocalTime reentrant, we manually copy
+      the structure into the (struct tm *) passed in.
+    */
+    tmp->tm_sec    = tm->tm_sec;
+    tmp->tm_min    = tm->tm_min;
+    tmp->tm_hour   = tm->tm_hour;
+    tmp->tm_mday   = tm->tm_mday;
+    tmp->tm_mon    = tm->tm_mon;
+    tmp->tm_year   = tm->tm_year;
+    tmp->tm_wday   = tm->tm_wday;
+    tmp->tm_yday   = tm->tm_yday;
+    tmp->tm_isdst  = tm->tm_isdst;
+    /*
+      If you don't have tm_zone in (struct tm), but
+      you get at it via the shared tmzone[], you'll
+      lose. Same goes for the tm_gmtoff field.
+    
+    */
+#if HAVE_TM_ZONE
+    strcpy(tmp->tm_zone,tm->tm_zone);
+    tmp->tm_gmtoff = tm->tm_gmtoff;
+#endif
+
+    return 1;
+}