Add a threaded test for g_object_replace_data

This is the threaded atomic add test from glib/tests/atomic.c,
redone using qdata instead of an atomic int to store the values.

gobject/tests/Makefile.am

@@ -12,6 +12,7 @@ noinst_PROGRAMS  = $(TEST_PROGS)
 LDADD = ../libgobject-2.0.la $(top_builddir)/gthread/libgthread-2.0.la $(top_builddir)/glib/libglib-2.0.la
 
 TEST_PROGS += 		\
+	qdata		\
 	boxed		\
 	enums		\
 	param		\

gobject/tests/qdata.c

@@ -0,0 +1,93 @@
+/*
+ * Copyright 2012 Red Hat, Inc.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or (at your option) any later version.
+ *
+ * See the included COPYING file for more information.
+ */
+
+#include <glib-object.h>
+
+gboolean fail;
+
+#define THREADS 10
+#define ROUNDS 10000
+
+GObject *object;
+volatile gint bucket[THREADS];
+
+static gpointer
+thread_func (gpointer data)
+{
+  gint idx = GPOINTER_TO_INT (data);
+  gint i;
+  gint d;
+  gint value;
+  gint new_value;
+
+  for (i = 0; i < ROUNDS; i++)
+    {
+      d = g_random_int_range (-10, 100);
+      bucket[idx] += d;
+retry:
+      value = GPOINTER_TO_INT (g_object_get_data (object, "test"));
+      new_value = value + d;
+      if (fail)
+        g_object_set_data (object, "test", GINT_TO_POINTER (new_value));
+      else
+        {
+          if (!g_object_replace_data (object, "test",
+                                      GINT_TO_POINTER (value),
+                                      GINT_TO_POINTER (new_value),
+                                      NULL, NULL))
+            goto retry;
+        }
+      g_thread_yield ();
+    }
+
+  return NULL;
+}
+
+static void
+test_qdata_threaded (void)
+{
+  gint sum;
+  gint i;
+  GThread *threads[THREADS];
+  gint result;
+
+  object = g_object_new (G_TYPE_OBJECT, NULL);
+  g_object_set_data (object, "test", GINT_TO_POINTER (0));
+
+  for (i = 0; i < THREADS; i++)
+    bucket[i] = 0;
+
+  for (i = 0; i < THREADS; i++)
+    threads[i] = g_thread_new ("qdata", thread_func, GINT_TO_POINTER (i));
+
+  for (i = 0; i < THREADS; i++)
+    g_thread_join (threads[i]);
+
+  sum = 0;
+  for (i = 0; i < THREADS; i++)
+    sum += bucket[i];
+
+  result = GPOINTER_TO_INT (g_object_get_data (object, "test"));
+
+  g_assert_cmpint (sum, ==, result);
+}
+
+int
+main (int argc, char **argv)
+{
+  g_test_init (&argc, &argv, NULL);
+  g_type_init ();
+  fail = !!g_getenv ("FAIL");
+
+  g_test_add_func ("/qdata/threaded", test_qdata_threaded);
+
+  return g_test_run ();
+}