[glib] gtimezone: consider a leading : in TZ environment variable

[Giovanni Campagna <gcampagna src gnome org>]

commit 1faed130dc227f983f42f23df2a242bd004c4ac8
Author: Giovanni Campagna <gcampagna src gnome org>
Date:   Thu Nov 17 00:52:59 2011 +0100

    gtimezone: consider a leading : in TZ environment variable
    
    When set to represent a zoneinfo file, TZ may start with :, therefore
    glib needs to check it and ignore the first char when building the
    resulting filename, or it won't be found.
    Also, the path could be absolute, in which case it is wrong to
    append /usr/share/timezone
    
    https://bugzilla.gnome.org/show_bug.cgi?id=664237

 glib/gtimezone.c |   12 +++++++++++-
 1 files changed, 11 insertions(+), 1 deletions(-)
---
diff --git a/glib/gtimezone.c b/glib/gtimezone.c
index 2785d22..8195106 100644
--- a/glib/gtimezone.c
+++ b/glib/gtimezone.c
@@ -368,6 +368,10 @@ g_time_zone_new (const gchar *identifier)
         {
           gchar *filename;
 
+	  /* identifier can be a relative or absolute path name;
+	     if relative, it is interpreted starting from /usr/share/timezone
+	     while the POSIX standard says it should start with :,
+	     glibc allows both syntaxes, so we should too */
           if (identifier != NULL)
             {
               const gchar *tzdir;
@@ -376,7 +380,13 @@ g_time_zone_new (const gchar *identifier)
               if (tzdir == NULL)
                 tzdir = "/usr/share/zoneinfo";
 
-              filename = g_build_filename (tzdir, identifier, NULL);
+	      if (*identifier == ':')
+		identifier ++;
+
+	      if (g_path_is_absolute (identifier))
+		filename = g_strdup (identifier);
+	      else
+		filename = g_build_filename (tzdir, identifier, NULL);
             }
           else
             filename = g_strdup ("/etc/localtime");