From 574d42327191bc1d38e2ac30b0cd20180bedbd44 Mon Sep 17 00:00:00 2001
From: robertl <robertl@f51c46e8-681c-474f-0cfe-069cfd0219fb>
Date: Wed, 8 Jan 2003 15:58:23 +0000
Subject: [PATCH] Fix up timezones on GPX input.  Combination of Park, Fouts,
 and myself.

---
 gpsbabel/gpx.c  | 14 +-------------
 gpsbabel/util.c | 18 ++++++++++++++++++
 2 files changed, 19 insertions(+), 13 deletions(-)

diff --git a/gpsbabel/gpx.c b/gpsbabel/gpx.c
index b73c84302..98af66274 100644
--- a/gpsbabel/gpx.c
+++ b/gpsbabel/gpx.c
@@ -388,19 +388,7 @@ gpx_end(void *data, const char *el)
 			tm.tm_mon -= 1;
 			tm.tm_year -= 1900;
 			tm.tm_isdst = 1;
-			wpt_tmp->creation_time = mktime(&tm);
-#if 0
-			/* mktime assumes local time, and Z is gmtime */
-			/* localtime will initialize timezone and daylight */
-			/* 12/31/02 - RJL - unfortunately, this fix relies
-			 * on non-ANSI extensions, so I've turned this off
-			 * and reverted to the old way.
-			 */
-			localtime( &wpt_tmp->creation_time );
-			wpt_tmp->creation_time -= timezone - (daylight?3600:0);
-#else
-                        wpt_tmp->creation_time = mktime(&tm);
-#endif
+                        wpt_tmp->creation_time = mktime(&tm) + get_tz_offset();
 		}
 		if (in_wpt && in_gs_type && !in_gs_log) {
 			wpt_tmp->gc_data.type = gs_mktype(cdatastr);
diff --git a/gpsbabel/util.c b/gpsbabel/util.c
index c74a6084a..3e64373c8 100644
--- a/gpsbabel/util.c
+++ b/gpsbabel/util.c
@@ -106,6 +106,7 @@ fprintdms(FILE *file, const coord *c, int is_lat)
 	}
 	fprintf(file, "%c%f\t", d, fabs(c->degrees));
 }
+
 void
 fatal(const char *fmt, ...)
 {
@@ -195,3 +196,20 @@ si_round( double d )
 		return (signed int)(d+0.5);
 	}
 }
+
+/*
+ *  Return a time_t suitable for adding to a time_t that is in GMT to
+ *  make it a local time.
+ */
+signed int 
+get_tz_offset(void)
+{
+	time_t now = time(0);
+	time_t later = mktime(gmtime(&now));
+
+	if (later == -1) {
+		return 0;
+	} else {
+		return (signed int) difftime(now, later);
+	}
+}
-- 
2.30.2