Merge lp:~mhr3/dee/fix-963991 into lp:dee

[Michal Hruby]

Prevent a possible crash when prefix searching near the end of sequence

Prefix searching near the end of the index sequence could cause a crash because we were calling g_sequence_get on the end iterator followed by dereferencing of a (possibly) NULL pointer.

Added a check whether the found iterator isn't end iterator.

Also added unit test for the issue.

[Gord Allott (gordallott)]

seems good

review: Approve

[Unity Merger (unity-merger)]

No commit message specified.

[Mikkel Kamstrup Erlandsen (kamstrup)]

Well, spotted. Rock on dude.

=== modified file 'src/dee-tree-index.c'
--- src/dee-tree-index.c	2012-03-16 11:48:56 +0000
+++ src/dee-tree-index.c	2012-04-02 10:51:21 +0000
@@ -266,7 +266,7 @@
           if (g_str_has_prefix (term_result->term, term)) iter = previous;
           else break;
         }
-      if (iter == found_iter)
+      if (iter == found_iter && iter != end)
         {
           /* We never checked this one */
           term_result = g_sequence_get (iter);

=== modified file 'tests/test-index.c'
--- tests/test-index.c	2012-02-28 09:59:38 +0000
+++ tests/test-index.c	2012-04-02 10:51:21 +0000
@@ -505,6 +505,47 @@
   g_assert_cmpint (dee_index_get_n_rows (fix->index), ==, 0);
   
 }
+
+static void
+test_prefix_search_empty (Fixture *fix, gconstpointer data)
+{
+  DeeResultSet *rs;
+
+  g_assert_cmpint (dee_index_get_n_rows (fix->index), ==, 0);
+  
+  rs = dee_index_lookup (fix->index, "a", DEE_TERM_MATCH_PREFIX);
+  g_assert_cmpuint (0, ==, dee_result_set_get_n_rows (rs));
+  g_object_unref (rs);
+}
+
+static void
+test_prefix_search_near_beginning (Fixture *fix, gconstpointer data)
+{
+  DeeResultSet *rs;
+
+  dee_model_append (fix->model, "vl", 44);
+  
+  g_assert_cmpint (dee_index_get_n_rows (fix->index), ==, 1);
+  
+  rs = dee_index_lookup (fix->index, "a", DEE_TERM_MATCH_PREFIX);
+  g_assert_cmpuint (0, ==, dee_result_set_get_n_rows (rs));
+  g_object_unref (rs);
+}
+
+static void
+test_prefix_search_near_end (Fixture *fix, gconstpointer data)
+{
+  DeeResultSet *rs;
+
+  dee_model_append (fix->model, "a", 44);
+  
+  g_assert_cmpint (dee_index_get_n_rows (fix->index), ==, 1);
+  
+  rs = dee_index_lookup (fix->index, "vl", DEE_TERM_MATCH_PREFIX);
+  g_assert_cmpuint (0, ==, dee_result_set_get_n_rows (rs));
+  g_object_unref (rs);
+}
+
 void
 test_hash_index_create_suite (void)
 {
@@ -544,4 +585,10 @@
               setup_text_tree, test_prefix_3_rows, teardown);
   g_test_add ("/Index/Tree/Prefix4RowsAndClear", Fixture, 0,
               setup_text_tree, test_prefix_4_rows_and_clear, teardown);
+  g_test_add ("/Index/Tree/PrefixSearchEmpty", Fixture, 0,
+              setup_text_tree, test_prefix_search_empty, teardown);
+  g_test_add ("/Index/Tree/PrefixSearchNearBeginning", Fixture, 0,
+              setup_text_tree, test_prefix_search_near_beginning, teardown);
+  g_test_add ("/Index/Tree/PrefixSearchNearEnd", Fixture, 0,
+              setup_text_tree, test_prefix_search_near_end, teardown);
 }