wmem: add foreach function to wmem_map.

Makes wmem_map more similar to g_hash.

Change-Id: Ia17a19ab0be8e07fbb64801d54db2ba8217a7fea
Reviewed-on: https://code.wireshark.org/review/15020
Petri-Dish: Anders Broman <a.broman58@gmail.com>
Tested-by: Petri Dish Buildbot <buildbot-no-reply@wireshark.org>
Reviewed-by: Anders Broman <a.broman58@gmail.com>

epan/wmem/wmem_map.c

@@ -214,6 +214,21 @@ wmem_map_remove(wmem_map_t *map, const void *key)
     return NULL;
 }
 
+void
+wmem_map_foreach(wmem_map_t *map, GHFunc foreach_func, gpointer user_data)
+{
+    wmem_map_item_t *cur;
+    unsigned i;
+
+    for (i = 0; i < CAPACITY(map); i++) {
+        cur = map->table[i];
+        while (cur) {
+            foreach_func((gpointer)cur->key, (gpointer)cur->value, user_data);
+            cur = cur->next;
+        }
+    }
+}
+
 /* Borrowed from Perl 5.18. This is based on Bob Jenkin's one-at-a-time
  * algorithm with some additional randomness seeded in. It is believed to be
  * generally secure against collision attacks. See

epan/wmem/wmem_map.h

@@ -102,6 +102,17 @@ WS_DLL_PUBLIC
 void *
 wmem_map_remove(wmem_map_t *map, const void *key);
 
+/** Run a function against all key/value pairs in the map. The order
+ * of the calls is unpredictable, since it is based on the internal
+ * storage of data.
+ *
+ * @param map The map to use
+ * @param foreach_func the function to call for each key/value pair
+ * @param user_data user data to pass to the function
+ */
+WS_DLL_PUBLIC
+void
+wmem_map_foreach(wmem_map_t *map, GHFunc foreach_func, gpointer user_data);
 
 /** Compute a strong hash value for an arbitrary sequence of bytes. Use of this
  * hash value should be secure against algorithmic complexity attacks, even for

epan/wmem/wmem_test.c

@@ -549,7 +549,7 @@ wmem_test_array(void)
 }
 
 static void
-checkval(gpointer val, gpointer val_to_check)
+check_val_list(gpointer val, gpointer val_to_check)
 {
     g_assert(val == val_to_check);
 }
@@ -646,10 +646,16 @@ wmem_test_list(void)
     for (i=0; i<CONTAINER_ITERS; i++) {
         wmem_list_append(list, GINT_TO_POINTER(1));
     }
-    wmem_list_foreach(list, checkval, GINT_TO_POINTER(1));
+    wmem_list_foreach(list, check_val_list, GINT_TO_POINTER(1));
     wmem_destroy_list(list);
 }
 
+void
+check_val_map(gpointer key _U_, gpointer val, gpointer user_data)
+{
+    g_assert(val == user_data);
+}
+
 static void
 wmem_test_map(void)
 {
@@ -696,6 +702,15 @@ wmem_test_map(void)
         g_assert(ret == GINT_TO_POINTER(i));
     }
 
+    /* test foreach */
+    map = wmem_map_new(allocator, wmem_str_hash, g_str_equal);
+    g_assert(map);
+    for (i=0; i<CONTAINER_ITERS; i++) {
+        str_key = wmem_test_rand_string(allocator, 1, 64);
+        wmem_map_insert(map, str_key, GINT_TO_POINTER(2));
+    }
+    wmem_map_foreach(map, check_val_map, GINT_TO_POINTER(2));
+
     wmem_destroy_allocator(allocator);
 }