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// 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 "base/bind.h"
#include "base/bind_helpers.h"
#include "base/callback.h"
#include "base/memory/ref_counted.h"
#include "base/memory/scoped_ptr.h"
#include "base/message_loop.h"
#include "base/synchronization/waitable_event.h"
#include "base/threading/thread.h"
#include "chrome/browser/sync/glue/ui_model_worker.h"
#include "content/public/test/test_browser_thread.h"
#include "testing/gtest/include/gtest/gtest.h"
using browser_sync::UIModelWorker;
using syncer::SyncerError;
using content::BrowserThread;
// Various boilerplate, primarily for the StopWithPendingWork test.
class UIModelWorkerVisitor {
public:
UIModelWorkerVisitor(base::WaitableEvent* was_run,
bool quit_loop)
: quit_loop_when_run_(quit_loop),
was_run_(was_run) { }
virtual ~UIModelWorkerVisitor() { }
virtual syncer::SyncerError DoWork() {
EXPECT_TRUE(BrowserThread::CurrentlyOn(BrowserThread::UI));
was_run_->Signal();
if (quit_loop_when_run_)
MessageLoop::current()->Quit();
return syncer::SYNCER_OK;
}
private:
bool quit_loop_when_run_;
base::WaitableEvent* was_run_;
DISALLOW_COPY_AND_ASSIGN(UIModelWorkerVisitor);
};
// A faux-syncer that only interacts with its model safe worker.
class Syncer {
public:
explicit Syncer(UIModelWorker* worker) : worker_(worker) {}
~Syncer() {}
void SyncShare(UIModelWorkerVisitor* visitor) {
// We wait until the callback is executed. So it is safe to use Unretained.
syncer::WorkCallback c = base::Bind(&UIModelWorkerVisitor::DoWork,
base::Unretained(visitor));
worker_->DoWorkAndWaitUntilDone(c);
}
private:
scoped_refptr<UIModelWorker> worker_;
DISALLOW_COPY_AND_ASSIGN(Syncer);
};
// A callback run from the CoreThread to simulate terminating syncapi.
void FakeSyncapiShutdownCallback(base::Thread* syncer_thread,
UIModelWorker* worker,
base::WaitableEvent** jobs,
size_t job_count) {
base::WaitableEvent all_jobs_done(false, false);
// In real life, we would try and close a sync directory, which would
// result in the syncer calling it's own destructor, which results in
// the SyncerThread::HaltSyncer being called, which sets the
// syncer in RequestEarlyExit mode and waits until the Syncer finishes
// SyncShare to remove the syncer from its watch. Here we just manually
// wait until all outstanding jobs are done to simulate what happens in
// SyncerThread::HaltSyncer.
all_jobs_done.WaitMany(jobs, job_count);
// These two calls are made from SyncBackendHost::Core::DoShutdown.
syncer_thread->Stop();
worker->OnSyncerShutdownComplete();
}
class SyncUIModelWorkerTest : public testing::Test {
public:
SyncUIModelWorkerTest() : faux_syncer_thread_("FauxSyncerThread"),
faux_core_thread_("FauxCoreThread") { }
virtual void SetUp() {
faux_syncer_thread_.Start();
ui_thread_.reset(new content::TestBrowserThread(BrowserThread::UI,
&faux_ui_loop_));
bmw_ = new UIModelWorker();
syncer_.reset(new Syncer(bmw_.get()));
}
Syncer* syncer() { return syncer_.get(); }
UIModelWorker* bmw() { return bmw_.get(); }
base::Thread* core_thread() { return &faux_core_thread_; }
base::Thread* syncer_thread() { return &faux_syncer_thread_; }
private:
MessageLoop faux_ui_loop_;
scoped_ptr<content::TestBrowserThread> ui_thread_;
base::Thread faux_syncer_thread_;
base::Thread faux_core_thread_;
scoped_refptr<UIModelWorker> bmw_;
scoped_ptr<Syncer> syncer_;
};
TEST_F(SyncUIModelWorkerTest, ScheduledWorkRunsOnUILoop) {
base::WaitableEvent v_was_run(false, false);
scoped_ptr<UIModelWorkerVisitor> v(
new UIModelWorkerVisitor(&v_was_run, true));
syncer_thread()->message_loop()->PostTask(FROM_HERE,
base::Bind(&Syncer::SyncShare, base::Unretained(syncer()), v.get()));
// We are on the UI thread, so run our loop to process the
// (hopefully) scheduled task from a SyncShare invocation.
MessageLoop::current()->Run();
bmw()->OnSyncerShutdownComplete();
bmw()->Stop();
syncer_thread()->Stop();
}
TEST_F(SyncUIModelWorkerTest, StopWithPendingWork) {
// What we want to set up is the following:
// ("ui_thread" is the thread we are currently executing on)
// 1 - simulate the user shutting down the browser, and the ui thread needing
// to terminate the core thread.
// 2 - the core thread is where the syncapi is accessed from, and so it needs
// to shut down the SyncerThread.
// 3 - the syncer is waiting on the UIModelWorker to
// perform a task for it.
// The UIModelWorker's manual shutdown pump will save the day, as the
// UI thread is not actually trying to join() the core thread, it is merely
// waiting for the SyncerThread to give it work or to finish. After that, it
// will join the core thread which should succeed as the SyncerThread has left
// the building. Unfortunately this test as written is not provably decidable,
// as it will always halt on success, but it may not on failure (namely if
// the task scheduled by the Syncer is _never_ run).
core_thread()->Start();
base::WaitableEvent v_ran(false, false);
scoped_ptr<UIModelWorkerVisitor> v(new UIModelWorkerVisitor(
&v_ran, false));
base::WaitableEvent* jobs[] = { &v_ran };
// The current message loop is not running, so queue a task to cause
// UIModelWorker::Stop() to play a crucial role. See comment below.
syncer_thread()->message_loop()->PostTask(FROM_HERE,
base::Bind(&Syncer::SyncShare, base::Unretained(syncer()), v.get()));
// This is what gets the core_thread blocked on the syncer_thread.
core_thread()->message_loop()->PostTask(FROM_HERE,
base::Bind(&FakeSyncapiShutdownCallback, syncer_thread(),
base::Unretained(bmw()),
static_cast<base::WaitableEvent**>(jobs), 1));
// This is what gets the UI thread blocked until NotifyExitRequested,
// which is called when FakeSyncapiShutdownCallback runs and deletes the
// syncer.
bmw()->Stop();
EXPECT_FALSE(syncer_thread()->IsRunning());
core_thread()->Stop();
}
TEST_F(SyncUIModelWorkerTest, HypotheticalManualPumpFlooding) {
// This situation should not happen in real life because the Syncer should
// never send more than one CallDoWork notification after early_exit_requested
// has been set, but our UIModelWorker is built to handle this case
// nonetheless. It may be needed in the future, and since we support it and
// it is not actually exercised in the wild this test is essential.
// It is identical to above except we schedule more than one visitor.
core_thread()->Start();
// Our ammunition.
base::WaitableEvent fox1_ran(false, false);
scoped_ptr<UIModelWorkerVisitor> fox1(new UIModelWorkerVisitor(
&fox1_ran, false));
base::WaitableEvent fox2_ran(false, false);
scoped_ptr<UIModelWorkerVisitor> fox2(new UIModelWorkerVisitor(
&fox2_ran, false));
base::WaitableEvent fox3_ran(false, false);
scoped_ptr<UIModelWorkerVisitor> fox3(new UIModelWorkerVisitor(
&fox3_ran, false));
base::WaitableEvent* jobs[] = { &fox1_ran, &fox2_ran, &fox3_ran };
// The current message loop is not running, so queue a task to cause
// UIModelWorker::Stop() to play a crucial role. See comment below.
syncer_thread()->message_loop()->PostTask(FROM_HERE,
base::Bind(&Syncer::SyncShare, base::Unretained(syncer()), fox1.get()));
syncer_thread()->message_loop()->PostTask(FROM_HERE,
base::Bind(&Syncer::SyncShare, base::Unretained(syncer()), fox2.get()));
// This is what gets the core_thread blocked on the syncer_thread.
core_thread()->message_loop()->PostTask(FROM_HERE,
base::Bind(&FakeSyncapiShutdownCallback, syncer_thread(),
base::Unretained(bmw()),
static_cast<base::WaitableEvent**>(jobs), 3));
syncer_thread()->message_loop()->PostTask(FROM_HERE,
base::Bind(&Syncer::SyncShare, base::Unretained(syncer()), fox3.get()));
// This is what gets the UI thread blocked until NotifyExitRequested,
// which is called when FakeSyncapiShutdownCallback runs and deletes the
// syncer.
bmw()->Stop();
// Was the thread killed?
EXPECT_FALSE(syncer_thread()->IsRunning());
core_thread()->Stop();
}
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