Bug #680687 - System timezone name differs from set in Gnome

diff --git a/calendar/libecal/e-cal-system-timezone.c b/calendar/libecal/e-cal-system-timezone.c
index bf7d523..dd51836 100644 (file)
--- a/calendar/libecal/e-cal-system-timezone.c
+++ b/calendar/libecal/e-cal-system-timezone.c
@@ -412,10 +412,10 @@ system_timezone_read_etc_localtime_content (GHashTable *ical_zones)
        static gchar *last_timezone = NULL;
        static GStaticRecMutex mutex = G_STATIC_REC_MUTEX_INIT;
 
-       struct stat  stat_localtime;
-       gchar   *localtime_content = NULL;
-       gsize   localtime_content_len = -1;
-       gchar   *retval, *fallback = NULL;
+       struct stat stat_localtime;
+       gchar *localtime_content = NULL;
+       gsize localtime_content_len = -1;
+       gchar *retval, *fallback = NULL;
 
        if (g_stat (ETC_LOCALTIME, &stat_localtime) != 0)
                return NULL;
@@ -478,13 +478,7 @@ system_timezone_read_etc_localtime_content (GHashTable *ical_zones)
 typedef gchar * (*GetSystemTimezone) (GHashTable *ical_zones);
 /* The order of the functions here define the priority of the methods used
  * to find the timezone. First method has higher priority. */
-static GetSystemTimezone get_system_timezone_methods[] = {
-       /* cheap and "more correct" than data from a config file */
-       system_timezone_read_etc_localtime_softlink,
-       /* reading /etc/timezone directly. Expensive since we have to stat
-        * many files, but it returns always correct values, even on KDE */
-       system_timezone_read_etc_localtime_content,
-       system_timezone_read_etc_localtime_hardlink,
+static GetSystemTimezone get_system_timezone_methods_config[] = {
        /* reading various config files */
        system_timezone_read_etc_timezone,
        system_timezone_read_etc_sysconfig_clock,
@@ -496,6 +490,14 @@ static GetSystemTimezone get_system_timezone_methods[] = {
        NULL
 };
 
+static GetSystemTimezone get_system_timezone_methods_slow[] = {
+       /* reading /etc/timezone directly. Expensive since we have to stat
+        * many files, but it returns always correct values, even on KDE */
+       system_timezone_read_etc_localtime_content,
+       system_timezone_read_etc_localtime_hardlink,
+       NULL
+};
+
 static gboolean
 system_timezone_is_valid (const gchar *tz,
                           GHashTable *ical_zones)
@@ -523,7 +525,7 @@ system_timezone_find (void)
        GHashTable *ical_zones;
        icalarray *builtin_timezones;
        gint ii;
-       gchar *tz;
+       gchar *tz, *config_tz = NULL;
 
        /* return only timezones known to libical */
        ical_zones = g_hash_table_new_full (g_str_hash, g_str_equal, g_free, NULL);
@@ -543,11 +545,74 @@ system_timezone_find (void)
                        g_hash_table_insert (ical_zones, g_strdup (location), GINT_TO_POINTER (1));
        }
 
-       for (ii = 0; get_system_timezone_methods[ii] != NULL; ii++) {
-               tz = get_system_timezone_methods[ii] (ical_zones);
+       /* softlink is the best option, it points to the correct file */
+       tz = system_timezone_read_etc_localtime_softlink (ical_zones);
+       if (system_timezone_is_valid (tz, ical_zones)) {
+               g_hash_table_destroy (ical_zones);
+               return tz;
+       }
+
+       g_free (tz);
+
+       config_tz = NULL;
+
+       /* read correct timezone name from config file; checking
+          on /etc/localtime content can pick wrong timezone name,
+          even the file is same
+        */
+       for (ii = 0; get_system_timezone_methods_config[ii] != NULL; ii++) {
+               config_tz = get_system_timezone_methods_config[ii] (ical_zones);
+
+               if (system_timezone_is_valid (config_tz, ical_zones)) {
+                       break;
+               }
+
+               g_free (config_tz);
+               config_tz = NULL;
+       }
+
+       if (config_tz) {
+               struct stat stat_localtime;
+               gchar *localtime_content = NULL;
+               gsize localtime_content_len = -1;
+
+               if (g_stat (ETC_LOCALTIME, &stat_localtime) == 0 &&
+                   S_ISREG (stat_localtime.st_mode) &&
+                   g_file_get_contents (ETC_LOCALTIME,
+                                        &localtime_content,
+                                        &localtime_content_len,
+                                        NULL)) {
+                       struct stat stat_config_tz;
+                       gchar *filename = g_build_filename (SYSTEM_ZONEINFODIR, config_tz, NULL);
+
+                       if (filename &&
+                           g_stat (filename, &stat_config_tz) == 0 &&
+                           files_are_identical_content (&stat_localtime,
+                               &stat_config_tz,
+                               localtime_content,
+                               localtime_content_len,
+                               filename)) {
+                               g_free (filename);
+                               g_free (localtime_content);
+
+                               /* corresponding file name to config_tz matches /etc/localtime,
+                                  thus that's the correct one - return it as system timezone;
+                                  bonus is that it might match configured system timezone name too
+                               */
+                               return config_tz;
+                       }
+                       g_free (filename);
+               }
+
+               g_free (localtime_content);
+       }
+
+       for (ii = 0; get_system_timezone_methods_slow[ii] != NULL; ii++) {
+               tz = get_system_timezone_methods_slow[ii] (ical_zones);
 
                if (system_timezone_is_valid (tz, ical_zones)) {
                        g_hash_table_destroy (ical_zones);
+                       g_free (config_tz);
                        return tz;
                }
 
@@ -556,7 +621,7 @@ system_timezone_find (void)
 
        g_hash_table_destroy (ical_zones);
 
-       return NULL;
+       return config_tz;
 }
 
 #else /* G_OS_WIN32 */