[babl] babl: fix memory leaks on error paths

[Øyvind Kolås <ok src gnome org>]

commit 23def34b96fb69cfe9ca3c8e8cee7c01383779ff
Author: Tobias Stoeckmann <tobias stoeckmann org>
Date:   Fri Oct 13 18:32:52 2017 +0200

    babl: fix memory leaks on error paths
    
    The database-focused functions of babl-cache are prone to
    memory leaks when errors occur.
    
    Signed-off-by: Tobias Stoeckmann <tobias stoeckmann org>

 babl/babl-cache.c |    7 +++++++
 1 files changed, 7 insertions(+), 0 deletions(-)
---
diff --git a/babl/babl-cache.c b/babl/babl-cache.c
index 13badc5..dcc76f4 100644
--- a/babl/babl-cache.c
+++ b/babl/babl-cache.c
@@ -170,10 +170,15 @@ void babl_store_db (void)
   char *tmpp = calloc(8000,1);
   FILE *dbfile;
 
+  if (!tmpp)
+    return;
   snprintf (tmpp, 8000, "%s~", fish_cache_path ());
   dbfile  = fopen (tmpp, "w");
   if (!dbfile)
+  {
+    free (tmpp);
     return;
+  }
   fprintf (dbfile, "%s\n", cache_header ());
 
   /* sort the list of fishes by usage, making next run more efficient -
@@ -273,6 +278,7 @@ void babl_init_db (void)
             {
               fprintf (stderr, "%s:%i: loading of cache failed\n",
                               __FUNCTION__, __LINE__);
+              free (contents);
               return;
             }
 
@@ -315,6 +321,7 @@ void babl_init_db (void)
             Babl *conv = (void*)babl_db_find(babl_conversion_db(), &token[1]);
             if (!conv)
             {
+              free (contents);
               return;
             }
             else