[glib/new-gsettings] add safety against corrupt gvdb files

[Ryan Lortie <ryanl src gnome org>]

commit 178225a04a70093e895a7572d63214df8188fdb0
Author: Ryan Lortie <desrt desrt ca>
Date:   Wed Apr 14 19:42:26 2010 -0400

    add safety against corrupt gvdb files

 gio/gvdb/gvdb-reader.c |    9 +++++----
 1 files changed, 5 insertions(+), 4 deletions(-)
---
diff --git a/gio/gvdb/gvdb-reader.c b/gio/gvdb/gvdb-reader.c
index 5f80d1f..c4ea31b 100644
--- a/gio/gvdb/gvdb-reader.c
+++ b/gio/gvdb/gvdb-reader.c
@@ -224,6 +224,7 @@ gvdb_table_lookup (GvdbTable   *file,
 {
   guint32 hash_value = 5381;
   guint key_length;
+  guint32 bucket;
   guint32 lastno;
   guint32 itemno;
 
@@ -236,11 +237,11 @@ gvdb_table_lookup (GvdbTable   *file,
   if (!gvdb_table_bloom_filter (file, hash_value))
     return NULL;
 
-  itemno = file->hash_buckets[hash_value % file->n_buckets];
+  bucket = hash_value % file->n_buckets;
+  itemno = file->hash_buckets[bucket];
 
-  if (hash_value % file->n_buckets != file->n_buckets - 1)
-    lastno = file->hash_buckets[hash_value % file->n_buckets + 1];
-  else
+  if (bucket == file->n_buckets - 1 ||
+      (lastno = file->hash_buckets[bucket + 1]) > file->n_hash_items)
     lastno = file->n_hash_items;
 
   while G_LIKELY (itemno < lastno)