[glib/glib-2-30] g_strcompress: check that source is non-NULL rather than just crashing

[Simon McVittie <smcv src gnome org>]

commit 7ddaec08f48296b451f12d47d9275f38eb46c7f3
Author: Simon McVittie <simon mcvittie collabora co uk>
Date:   Mon Dec 12 18:37:10 2011 +0000

    g_strcompress: check that source is non-NULL rather than just crashing
    
    Calling this function with a NULL argument is considered to be invalid,
    but one of the regression tests does it anyway (to watch it crash), which
    seems a good indication that it's expected to be somewhat common.
    Let's check it rather than segfaulting.
    
    Signed-off-by: Simon McVittie <simon mcvittie collabora co uk>
    Bug: https://bugzilla.gnome.org/show_bug.cgi?id=666113
    Reviewed-by: Emmanuele Bassi <ebassi linux intel com>
    Reviewed-by: Matthias Clasen <mclasen redhat com>

 glib/gstrfuncs.c |    9 +++++++--
 1 files changed, 7 insertions(+), 2 deletions(-)
---
diff --git a/glib/gstrfuncs.c b/glib/gstrfuncs.c
index aecde5b..aa9decd 100644
--- a/glib/gstrfuncs.c
+++ b/glib/gstrfuncs.c
@@ -2207,8 +2207,13 @@ gchar*
 g_strcompress (const gchar *source)
 {
   const gchar *p = source, *octal;
-  gchar *dest = g_malloc (strlen (source) + 1);
-  gchar *q = dest;
+  gchar *dest;
+  gchar *q;
+
+  g_return_val_if_fail (source != NULL, NULL);
+
+  dest = g_malloc (strlen (source) + 1);
+  q = dest;
 
   while (*p)
     {