PPAPI: Make PPB_MessageLoop_Dev::GetForMainThread work

ppapi/tests/test_message_loop.cc

+// Copyright (c) 2012 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "ppapi/tests/test_message_loop.h"
+
+#include "ppapi/c/pp_macros.h"
+#include "ppapi/cpp/core.h"
+#include "ppapi/cpp/logging.h"
+#include "ppapi/cpp/module.h"
+#include "ppapi/cpp/dev/message_loop_dev.h"
+#include "ppapi/tests/testing_instance.h"
+#include "ppapi/utility/threading/simple_thread.h"
+
+REGISTER_TEST_CASE(MessageLoop);
+
+TestMessageLoop::TestMessageLoop(TestingInstance* instance)
+    : TestCase(instance),
+      param_(kInvalid),
+      PP_ALLOW_THIS_IN_INITIALIZER_LIST(callback_factory_(this)),
+      main_loop_task_ran_(instance->pp_instance()) {
+}
+
+TestMessageLoop::~TestMessageLoop() {
+}
+
+void TestMessageLoop::RunTests(const std::string& filter) {
+  RUN_TEST(Basics, filter);
+  RUN_TEST(Post, filter);
+}
+
+std::string TestMessageLoop::TestBasics() {
+  // The main thread message loop should be valid, and equal to the "current"
+  // one.
+  ASSERT_NE(0, pp::MessageLoop_Dev::GetForMainThread().pp_resource());
+  ASSERT_EQ(pp::MessageLoop_Dev::GetForMainThread().pp_resource(),
+            pp::MessageLoop_Dev::GetCurrent().pp_resource());
+
+  // We shouldn't be able to attach a new loop to the main thread.
+  pp::MessageLoop_Dev loop(instance_);
+  ASSERT_EQ(PP_ERROR_INPROGRESS, loop.AttachToCurrentThread());
+
+  // Nested loops aren't allowed.
+  ASSERT_EQ(PP_ERROR_INPROGRESS,
+            pp::MessageLoop_Dev::GetForMainThread().Run());
+
+  // We can't run on a loop that isn't attached to a thread.
+  ASSERT_EQ(PP_ERROR_WRONG_THREAD, loop.Run());
+
+  PASS();
+}
+
+std::string TestMessageLoop::TestPost() {
+  // Make sure we can post a task from the main thread back to the main thread.
+  pp::MessageLoop_Dev::GetCurrent().PostWork(callback_factory_.NewCallback(
+      &TestMessageLoop::SetParamAndQuitTask, kMainToMain));
+  main_loop_task_ran_.Wait();
+  ASSERT_EQ(param_, kMainToMain);
+  main_loop_task_ran_.Reset();
+
+  pp::SimpleThread thread(instance_);
+  // Post a task before the thread is started, to make sure it is run.
+  // TODO(dmichael): CompletionCallbackFactory is not 100% thread safe for
+  // posting tasks to a thread other than where the factory was created. It
+  // should be OK for this test, since we know that the
+  // CompletionCallbackFactory and its target object outlive all callbacks. But
+  // developers are likely to misuse CompletionCallbackFactory. Maybe we should
+  // make it safe to use a callback on another thread?
+  thread.message_loop().PostWork(callback_factory_.NewCallback(
+      &TestMessageLoop::EchoParamToMainTask, kBeforeStart));
+  ASSERT_TRUE(thread.Start());
+  main_loop_task_ran_.Wait();
+  ASSERT_EQ(param_, kBeforeStart);
+  main_loop_task_ran_.Reset();
+
+  // Now post another one after start. This is the more normal case.
+
+  // Nested loops aren't allowed.
+  ASSERT_EQ(PP_ERROR_INPROGRESS,
+            pp::MessageLoop_Dev::GetForMainThread().Run());
+  thread.message_loop().PostWork(callback_factory_.NewCallback(
+      &TestMessageLoop::EchoParamToMainTask, kAfterStart));
+  main_loop_task_ran_.Wait();
+  ASSERT_EQ(param_, kAfterStart);
+  main_loop_task_ran_.Reset();
+
+  // Quit and join the thread.
+  ASSERT_TRUE(thread.Join());
+
+  PASS();
+}
+
+void TestMessageLoop::SetParamAndQuitTask(int32_t result, TestParam param) {
+  PP_DCHECK(result == PP_OK);
+  param_ = param;
+  main_loop_task_ran_.Signal();
+}
+
+void TestMessageLoop::EchoParamToMainTask(int32_t result, TestParam param) {
+  PP_DCHECK(result == PP_OK);
+  pp::MessageLoop_Dev::GetForMainThread().PostWork(
+      callback_factory_.NewCallback(
+          &TestMessageLoop::SetParamAndQuitTask, param));
+}
+