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// Copyright (c) 2010 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 <vector>

#include "base/eintr_wrapper.h"
#include "base/logging.h"
#include "base/message_loop.h"
#include "base/platform_thread.h"
#include "base/ref_counted.h"
#include "base/task.h"
#include "base/thread.h"
#include "testing/gtest/include/gtest/gtest.h"

#if defined(OS_WIN)
#include "base/message_pump_win.h"
#include "base/scoped_handle.h"
#endif
#if defined(OS_POSIX)
#include "base/message_pump_libevent.h"
#endif

using base::Thread;
using base::Time;
using base::TimeDelta;

// TODO(darin): Platform-specific MessageLoop tests should be grouped together
// to avoid chopping this file up with so many #ifdefs.

namespace {

class MessageLoopTest : public testing::Test {};

class Foo : public base::RefCounted<Foo> {
 public:
  Foo() : test_count_(0) {
  }

  void Test0() {
    ++test_count_;
  }

  void Test1ConstRef(const std::string& a) {
    ++test_count_;
    result_.append(a);
  }

  void Test1Ptr(std::string* a) {
    ++test_count_;
    result_.append(*a);
  }

  void Test1Int(int a) {
    test_count_ += a;
  }

  void Test2Ptr(std::string* a, std::string* b) {
    ++test_count_;
    result_.append(*a);
    result_.append(*b);
  }

  void Test2Mixed(const std::string& a, std::string* b) {
    ++test_count_;
    result_.append(a);
    result_.append(*b);
  }

  int test_count() const { return test_count_; }
  const std::string& result() const { return result_; }

 private:
  friend class base::RefCounted<Foo>;

  ~Foo() {}

  int test_count_;
  std::string result_;
};

class QuitMsgLoop : public base::RefCounted<QuitMsgLoop> {
 public:
  void QuitNow() {
    MessageLoop::current()->Quit();
  }

 private:
  friend class base::RefCounted<QuitMsgLoop>;

  ~QuitMsgLoop() {}
};

void RunTest_PostTask(MessageLoop::Type message_loop_type) {
  MessageLoop loop(message_loop_type);

  // Add tests to message loop
  scoped_refptr<Foo> foo(new Foo());
  std::string a("a"), b("b"), c("c"), d("d");
  MessageLoop::current()->PostTask(FROM_HERE, NewRunnableMethod(
      foo.get(), &Foo::Test0));
  MessageLoop::current()->PostTask(FROM_HERE, NewRunnableMethod(
    foo.get(), &Foo::Test1ConstRef, a));
  MessageLoop::current()->PostTask(FROM_HERE, NewRunnableMethod(
      foo.get(), &Foo::Test1Ptr, &b));
  MessageLoop::current()->PostTask(FROM_HERE, NewRunnableMethod(
      foo.get(), &Foo::Test1Int, 100));
  MessageLoop::current()->PostTask(FROM_HERE, NewRunnableMethod(
      foo.get(), &Foo::Test2Ptr, &a, &c));
  MessageLoop::current()->PostTask(FROM_HERE, NewRunnableMethod(
    foo.get(), &Foo::Test2Mixed, a, &d));

  // After all tests, post a message that will shut down the message loop
  scoped_refptr<QuitMsgLoop> quit(new QuitMsgLoop());
  MessageLoop::current()->PostTask(FROM_HERE, NewRunnableMethod(
      quit.get(), &QuitMsgLoop::QuitNow));

  // Now kick things off
  MessageLoop::current()->Run();

  EXPECT_EQ(foo->test_count(), 105);
  EXPECT_EQ(foo->result(), "abacad");
}

void RunTest_PostTask_SEH(MessageLoop::Type message_loop_type) {
  MessageLoop loop(message_loop_type);

  // Add tests to message loop
  scoped_refptr<Foo> foo(new Foo());
  std::string a("a"), b("b"), c("c"), d("d");
  MessageLoop::current()->PostTask(FROM_HERE, NewRunnableMethod(
      foo.get(), &Foo::Test0));
  MessageLoop::current()->PostTask(FROM_HERE, NewRunnableMethod(
      foo.get(), &Foo::Test1ConstRef, a));
  MessageLoop::current()->PostTask(FROM_HERE, NewRunnableMethod(
      foo.get(), &Foo::Test1Ptr, &b));
  MessageLoop::current()->PostTask(FROM_HERE, NewRunnableMethod(
      foo.get(), &Foo::Test1Int, 100));
  MessageLoop::current()->PostTask(FROM_HERE, NewRunnableMethod(
      foo.get(), &Foo::Test2Ptr, &a, &c));
  MessageLoop::current()->PostTask(FROM_HERE, NewRunnableMethod(
      foo.get(), &Foo::Test2Mixed, a, &d));

  // After all tests, post a message that will shut down the message loop
  scoped_refptr<QuitMsgLoop> quit(new QuitMsgLoop());
  MessageLoop::current()->PostTask(FROM_HERE, NewRunnableMethod(
      quit.get(), &QuitMsgLoop::QuitNow));

  // Now kick things off with the SEH block active.
  MessageLoop::current()->set_exception_restoration(true);
  MessageLoop::current()->Run();
  MessageLoop::current()->set_exception_restoration(false);

  EXPECT_EQ(foo->test_count(), 105);
  EXPECT_EQ(foo->result(), "abacad");
}

// This class runs slowly to simulate a large amount of work being done.
class SlowTask : public Task {
 public:
  SlowTask(int pause_ms, int* quit_counter)
      : pause_ms_(pause_ms), quit_counter_(quit_counter) {
  }
  virtual void Run() {
    PlatformThread::Sleep(pause_ms_);
    if (--(*quit_counter_) == 0)
      MessageLoop::current()->Quit();
  }
 private:
  int pause_ms_;
  int* quit_counter_;
};

// This class records the time when Run was called in a Time object, which is
// useful for building a variety of MessageLoop tests.
class RecordRunTimeTask : public SlowTask {
 public:
  RecordRunTimeTask(Time* run_time, int* quit_counter)
      : SlowTask(10, quit_counter), run_time_(run_time) {
  }
  virtual void Run() {
    *run_time_ = Time::Now();
    // Cause our Run function to take some time to execute.  As a result we can
    // count on subsequent RecordRunTimeTask objects running at a future time,
    // without worry about the resolution of our system clock being an issue.
    SlowTask::Run();
  }
 private:
  Time* run_time_;
};

void RunTest_PostDelayedTask_Basic(MessageLoop::Type message_loop_type) {
  MessageLoop loop(message_loop_type);

  // Test that PostDelayedTask results in a delayed task.

  const int kDelayMS = 100;

  int num_tasks = 1;
  Time run_time;

  loop.PostDelayedTask(
      FROM_HERE, new RecordRunTimeTask(&run_time, &num_tasks), kDelayMS);

  Time time_before_run = Time::Now();
  loop.Run();
  Time time_after_run = Time::Now();

  EXPECT_EQ(0, num_tasks);
  EXPECT_LT(kDelayMS, (time_after_run - time_before_run).InMilliseconds());
}

void RunTest_PostDelayedTask_InDelayOrder(MessageLoop::Type message_loop_type) {
  MessageLoop loop(message_loop_type);

  // Test that two tasks with different delays run in the right order.

  int num_tasks = 2;
  Time run_time1, run_time2;

  loop.PostDelayedTask(
      FROM_HERE, new RecordRunTimeTask(&run_time1, &num_tasks), 200);
  // If we get a large pause in execution (due to a context switch) here, this
  // test could fail.
  loop.PostDelayedTask(
      FROM_HERE, new RecordRunTimeTask(&run_time2, &num_tasks), 10);

  loop.Run();
  EXPECT_EQ(0, num_tasks);

  EXPECT_TRUE(run_time2 < run_time1);
}

void RunTest_PostDelayedTask_InPostOrder(MessageLoop::Type message_loop_type) {
  MessageLoop loop(message_loop_type);

  // Test that two tasks with the same delay run in the order in which they
  // were posted.
  //
  // NOTE: This is actually an approximate test since the API only takes a
  // "delay" parameter, so we are not exactly simulating two tasks that get
  // posted at the exact same time.  It would be nice if the API allowed us to
  // specify the desired run time.

  const int kDelayMS = 100;

  int num_tasks = 2;
  Time run_time1, run_time2;

  loop.PostDelayedTask(
      FROM_HERE, new RecordRunTimeTask(&run_time1, &num_tasks), kDelayMS);
  loop.PostDelayedTask(
      FROM_HERE, new RecordRunTimeTask(&run_time2, &num_tasks), kDelayMS);

  loop.Run();
  EXPECT_EQ(0, num_tasks);

  EXPECT_TRUE(run_time1 < run_time2);
}

void RunTest_PostDelayedTask_InPostOrder_2(
    MessageLoop::Type message_loop_type) {
  MessageLoop loop(message_loop_type);

  // Test that a delayed task still runs after a normal tasks even if the
  // normal tasks take a long time to run.

  const int kPauseMS = 50;

  int num_tasks = 2;
  Time run_time;

  loop.PostTask(
      FROM_HERE, new SlowTask(kPauseMS, &num_tasks));
  loop.PostDelayedTask(
      FROM_HERE, new RecordRunTimeTask(&run_time, &num_tasks), 10);

  Time time_before_run = Time::Now();
  loop.Run();
  Time time_after_run = Time::Now();

  EXPECT_EQ(0, num_tasks);

  EXPECT_LT(kPauseMS, (time_after_run - time_before_run).InMilliseconds());
}

void RunTest_PostDelayedTask_InPostOrder_3(
    MessageLoop::Type message_loop_type) {
  MessageLoop loop(message_loop_type);

  // Test that a delayed task still runs after a pile of normal tasks.  The key
  // difference between this test and the previous one is that here we return
  // the MessageLoop a lot so we give the MessageLoop plenty of opportunities
  // to maybe run the delayed task.  It should know not to do so until the
  // delayed task's delay has passed.

  int num_tasks = 11;
  Time run_time1, run_time2;

  // Clutter the ML with tasks.
  for (int i = 1; i < num_tasks; ++i)
    loop.PostTask(FROM_HERE, new RecordRunTimeTask(&run_time1, &num_tasks));

  loop.PostDelayedTask(
      FROM_HERE, new RecordRunTimeTask(&run_time2, &num_tasks), 1);

  loop.Run();
  EXPECT_EQ(0, num_tasks);

  EXPECT_TRUE(run_time2 > run_time1);
}

void RunTest_PostDelayedTask_SharedTimer(MessageLoop::Type message_loop_type) {
  MessageLoop loop(message_loop_type);

  // Test that the interval of the timer, used to run the next delayed task, is
  // set to a value corresponding to when the next delayed task should run.

  // By setting num_tasks to 1, we ensure that the first task to run causes the
  // run loop to exit.
  int num_tasks = 1;
  Time run_time1, run_time2;

  loop.PostDelayedTask(
      FROM_HERE, new RecordRunTimeTask(&run_time1, &num_tasks), 1000000);
  loop.PostDelayedTask(
      FROM_HERE, new RecordRunTimeTask(&run_time2, &num_tasks), 10);

  Time start_time = Time::Now();

  loop.Run();
  EXPECT_EQ(0, num_tasks);

  // Ensure that we ran in far less time than the slower timer.
  TimeDelta total_time = Time::Now() - start_time;
  EXPECT_GT(5000, total_time.InMilliseconds());

  // In case both timers somehow run at nearly the same time, sleep a little
  // and then run all pending to force them both to have run.  This is just
  // encouraging flakiness if there is any.
  PlatformThread::Sleep(100);
  loop.RunAllPending();

  EXPECT_TRUE(run_time1.is_null());
  EXPECT_FALSE(run_time2.is_null());
}

#if defined(OS_WIN)

class SubPumpTask : public Task {
 public:
  virtual void Run() {
    MessageLoop::current()->SetNestableTasksAllowed(true);
    MSG msg;
    while (GetMessage(&msg, NULL, 0, 0)) {
      TranslateMessage(&msg);
      DispatchMessage(&msg);
    }
    MessageLoop::current()->Quit();
  }
};

class SubPumpQuitTask : public Task {
 public:
  SubPumpQuitTask() {
  }
  virtual void Run() {
    PostQuitMessage(0);
  }
};

void RunTest_PostDelayedTask_SharedTimer_SubPump() {
  MessageLoop loop(MessageLoop::TYPE_UI);

  // Test that the interval of the timer, used to run the next delayed task, is
  // set to a value corresponding to when the next delayed task should run.

  // By setting num_tasks to 1, we ensure that the first task to run causes the
  // run loop to exit.
  int num_tasks = 1;
  Time run_time;

  loop.PostTask(FROM_HERE, new SubPumpTask());

  // This very delayed task should never run.
  loop.PostDelayedTask(
      FROM_HERE, new RecordRunTimeTask(&run_time, &num_tasks), 1000000);

  // This slightly delayed task should run from within SubPumpTask::Run().
  loop.PostDelayedTask(
      FROM_HERE, new SubPumpQuitTask(), 10);

  Time start_time = Time::Now();

  loop.Run();
  EXPECT_EQ(1, num_tasks);

  // Ensure that we ran in far less time than the slower timer.
  TimeDelta total_time = Time::Now() - start_time;
  EXPECT_GT(5000, total_time.InMilliseconds());

  // In case both timers somehow run at nearly the same time, sleep a little
  // and then run all pending to force them both to have run.  This is just
  // encouraging flakiness if there is any.
  PlatformThread::Sleep(100);
  loop.RunAllPending();

  EXPECT_TRUE(run_time.is_null());
}

#endif  // defined(OS_WIN)

class RecordDeletionTask : public Task {
 public:
  RecordDeletionTask(Task* post_on_delete, bool* was_deleted)
      : post_on_delete_(post_on_delete), was_deleted_(was_deleted) {
  }
  ~RecordDeletionTask() {
    *was_deleted_ = true;
    if (post_on_delete_)
      MessageLoop::current()->PostTask(FROM_HERE, post_on_delete_);
  }
  virtual void Run() {}
 private:
  Task* post_on_delete_;
  bool* was_deleted_;
};

void RunTest_EnsureTaskDeletion(MessageLoop::Type message_loop_type) {
  bool a_was_deleted = false;
  bool b_was_deleted = false;
  {
    MessageLoop loop(message_loop_type);
    loop.PostTask(
        FROM_HERE, new RecordDeletionTask(NULL, &a_was_deleted));
    loop.PostDelayedTask(
        FROM_HERE, new RecordDeletionTask(NULL, &b_was_deleted), 1000);
  }
  EXPECT_TRUE(a_was_deleted);
  EXPECT_TRUE(b_was_deleted);
}

void RunTest_EnsureTaskDeletion_Chain(MessageLoop::Type message_loop_type) {
  bool a_was_deleted = false;
  bool b_was_deleted = false;
  bool c_was_deleted = false;
  {
    MessageLoop loop(message_loop_type);
    RecordDeletionTask* a = new RecordDeletionTask(NULL, &a_was_deleted);
    RecordDeletionTask* b = new RecordDeletionTask(a, &b_was_deleted);
    RecordDeletionTask* c = new RecordDeletionTask(b, &c_was_deleted);
    loop.PostTask(FROM_HERE, c);
  }
  EXPECT_TRUE(a_was_deleted);
  EXPECT_TRUE(b_was_deleted);
  EXPECT_TRUE(c_was_deleted);
}

class NestingTest : public Task {
 public:
  explicit NestingTest(int* depth) : depth_(depth) {
  }
  void Run() {
    if (*depth_ > 0) {
      *depth_ -= 1;
      MessageLoop::current()->PostTask(FROM_HERE, new NestingTest(depth_));

      MessageLoop::current()->SetNestableTasksAllowed(true);
      MessageLoop::current()->Run();
    }
    MessageLoop::current()->Quit();
  }
 private:
  int* depth_;
};

#if defined(OS_WIN)

LONG WINAPI BadExceptionHandler(EXCEPTION_POINTERS *ex_info) {
  ADD_FAILURE() << "bad exception handler";
  ::ExitProcess(ex_info->ExceptionRecord->ExceptionCode);
  return EXCEPTION_EXECUTE_HANDLER;
}

// This task throws an SEH exception: initially write to an invalid address.
// If the right SEH filter is installed, it will fix the error.
class CrasherTask : public Task {
 public:
  // Ctor. If trash_SEH_handler is true, the task will override the unhandled
  // exception handler with one sure to crash this test.
  explicit CrasherTask(bool trash_SEH_handler)
      : trash_SEH_handler_(trash_SEH_handler) {
  }
  void Run() {
    PlatformThread::Sleep(1);
    if (trash_SEH_handler_)
      ::SetUnhandledExceptionFilter(&BadExceptionHandler);
    // Generate a SEH fault. We do it in asm to make sure we know how to undo
    // the damage.

#if defined(_M_IX86)

    __asm {
      mov eax, dword ptr [CrasherTask::bad_array_]
      mov byte ptr [eax], 66
    }

#elif defined(_M_X64)

    bad_array_[0] = 66;

#else
#error "needs architecture support"
#endif

    MessageLoop::current()->Quit();
  }
  // Points the bad array to a valid memory location.
  static void FixError() {
    bad_array_ = &valid_store_;
  }

 private:
  bool trash_SEH_handler_;
  static volatile char* bad_array_;
  static char valid_store_;
};

volatile char* CrasherTask::bad_array_ = 0;
char CrasherTask::valid_store_ = 0;

// This SEH filter fixes the problem and retries execution. Fixing requires
// that the last instruction: mov eax, [CrasherTask::bad_array_] to be retried
// so we move the instruction pointer 5 bytes back.
LONG WINAPI HandleCrasherTaskException(EXCEPTION_POINTERS *ex_info) {
  if (ex_info->ExceptionRecord->ExceptionCode != EXCEPTION_ACCESS_VIOLATION)
    return EXCEPTION_EXECUTE_HANDLER;

  CrasherTask::FixError();

#if defined(_M_IX86)

  ex_info->ContextRecord->Eip -= 5;

#elif defined(_M_X64)

  ex_info->ContextRecord->Rip -= 5;

#endif

  return EXCEPTION_CONTINUE_EXECUTION;
}

void RunTest_Crasher(MessageLoop::Type message_loop_type) {
  MessageLoop loop(message_loop_type);

  if (::IsDebuggerPresent())
    return;

  LPTOP_LEVEL_EXCEPTION_FILTER old_SEH_filter =
      ::SetUnhandledExceptionFilter(&HandleCrasherTaskException);

  MessageLoop::current()->PostTask(FROM_HERE, new CrasherTask(false));
  MessageLoop::current()->set_exception_restoration(true);
  MessageLoop::current()->Run();
  MessageLoop::current()->set_exception_restoration(false);

  ::SetUnhandledExceptionFilter(old_SEH_filter);
}

void RunTest_CrasherNasty(MessageLoop::Type message_loop_type) {
  MessageLoop loop(message_loop_type);

  if (::IsDebuggerPresent())
    return;

  LPTOP_LEVEL_EXCEPTION_FILTER old_SEH_filter =
      ::SetUnhandledExceptionFilter(&HandleCrasherTaskException);

  MessageLoop::current()->PostTask(FROM_HERE, new CrasherTask(true));
  MessageLoop::current()->set_exception_restoration(true);
  MessageLoop::current()->Run();
  MessageLoop::current()->set_exception_restoration(false);

  ::SetUnhandledExceptionFilter(old_SEH_filter);
}

#endif  // defined(OS_WIN)

void RunTest_Nesting(MessageLoop::Type message_loop_type) {
  MessageLoop loop(message_loop_type);

  int depth = 100;
  MessageLoop::current()->PostTask(FROM_HERE, new NestingTest(&depth));
  MessageLoop::current()->Run();
  EXPECT_EQ(depth, 0);
}

const wchar_t* const kMessageBoxTitle = L"MessageLoop Unit Test";

enum TaskType {
  MESSAGEBOX,
  ENDDIALOG,
  RECURSIVE,
  TIMEDMESSAGELOOP,
  QUITMESSAGELOOP,
  ORDERERD,
  PUMPS,
  SLEEP,
};

// Saves the order in which the tasks executed.
struct TaskItem {
  TaskItem(TaskType t, int c, bool s)
      : type(t),
        cookie(c),
        start(s) {
  }

  TaskType type;
  int cookie;
  bool start;

  bool operator == (const TaskItem& other) const {
    return type == other.type && cookie == other.cookie && start == other.start;
  }
};

typedef std::vector<TaskItem> TaskList;

std::ostream& operator <<(std::ostream& os, TaskType type) {
  switch (type) {
  case MESSAGEBOX:        os << "MESSAGEBOX"; break;
  case ENDDIALOG:         os << "ENDDIALOG"; break;
  case RECURSIVE:         os << "RECURSIVE"; break;
  case TIMEDMESSAGELOOP:  os << "TIMEDMESSAGELOOP"; break;
  case QUITMESSAGELOOP:   os << "QUITMESSAGELOOP"; break;
  case ORDERERD:          os << "ORDERERD"; break;
  case PUMPS:             os << "PUMPS"; break;
  case SLEEP:             os << "SLEEP"; break;
  default:
    NOTREACHED();
    os << "Unknown TaskType";
    break;
  }
  return os;
}

std::ostream& operator <<(std::ostream& os, const TaskItem& item) {
  if (item.start)
    return os << item.type << " " << item.cookie << " starts";
  else
    return os << item.type << " " << item.cookie << " ends";
}

// Saves the order the tasks ran.
class OrderedTasks : public Task {
 public:
  OrderedTasks(TaskList* order, int cookie)
      : order_(order),
        type_(ORDERERD),
        cookie_(cookie) {
  }
  OrderedTasks(TaskList* order, TaskType type, int cookie)
      : order_(order),
        type_(type),
        cookie_(cookie) {
  }

  void RunStart() {
    TaskItem item(type_, cookie_, true);
    DVLOG(1) << item;
    order_->push_back(item);
  }
  void RunEnd() {
    TaskItem item(type_, cookie_, false);
    DVLOG(1) << item;
    order_->push_back(item);
  }

  virtual void Run() {
    RunStart();
    RunEnd();
  }

 protected:
  TaskList* order() const {
    return order_;
  }

  int cookie() const {
    return cookie_;
  }

 private:
  TaskList* order_;
  TaskType type_;
  int cookie_;
};

#if defined(OS_WIN)

// MessageLoop implicitly start a "modal message loop". Modal dialog boxes,
// common controls (like OpenFile) and StartDoc printing function can cause
// implicit message loops.
class MessageBoxTask : public OrderedTasks {
 public:
  MessageBoxTask(TaskList* order, int cookie, bool is_reentrant)
      : OrderedTasks(order, MESSAGEBOX, cookie),
        is_reentrant_(is_reentrant) {
  }

  virtual void Run() {
    RunStart();
    if (is_reentrant_)
      MessageLoop::current()->SetNestableTasksAllowed(true);
    MessageBox(NULL, L"Please wait...", kMessageBoxTitle, MB_OK);
    RunEnd();
  }

 private:
  bool is_reentrant_;
};

// Will end the MessageBox.
class EndDialogTask : public OrderedTasks {
 public:
  EndDialogTask(TaskList* order, int cookie)
      : OrderedTasks(order, ENDDIALOG, cookie) {
  }

  virtual void Run() {
    RunStart();
    HWND window = GetActiveWindow();
    if (window != NULL) {
      EXPECT_NE(EndDialog(window, IDCONTINUE), 0);
      // Cheap way to signal that the window wasn't found if RunEnd() isn't
      // called.
      RunEnd();
    }
  }
};

#endif  // defined(OS_WIN)

class RecursiveTask : public OrderedTasks {
 public:
  RecursiveTask(int depth, TaskList* order, int cookie, bool is_reentrant)
      : OrderedTasks(order, RECURSIVE, cookie),
        depth_(depth),
        is_reentrant_(is_reentrant) {
  }

  virtual void Run() {
    RunStart();
    if (depth_ > 0) {
      if (is_reentrant_)
        MessageLoop::current()->SetNestableTasksAllowed(true);
      MessageLoop::current()->PostTask(FROM_HERE,
          new RecursiveTask(depth_ - 1, order(), cookie(), is_reentrant_));
    }
    RunEnd();
  }

 private:
  int depth_;
  bool is_reentrant_;
};

class QuitTask : public OrderedTasks {
 public:
  QuitTask(TaskList* order, int cookie)
      : OrderedTasks(order, QUITMESSAGELOOP, cookie) {
  }

  virtual void Run() {
    RunStart();
    MessageLoop::current()->Quit();
    RunEnd();
  }
};

class SleepTask : public OrderedTasks {
 public:
  SleepTask(TaskList* order, int cookie, int ms)
      : OrderedTasks(order, SLEEP, cookie), ms_(ms) {
  }

  virtual void Run() {
    RunStart();
    PlatformThread::Sleep(ms_);
    RunEnd();
  }

 private:
  int ms_;
};

#if defined(OS_WIN)

class Recursive2Tasks : public Task {
 public:
  Recursive2Tasks(MessageLoop* target,
                  HANDLE event,
                  bool expect_window,
                  TaskList* order,
                  bool is_reentrant)
      : target_(target),
        event_(event),
        expect_window_(expect_window),
        order_(order),
        is_reentrant_(is_reentrant) {
  }

  virtual void Run() {
    target_->PostTask(FROM_HERE,
                      new RecursiveTask(2, order_, 1, is_reentrant_));
    target_->PostTask(FROM_HERE,
                      new MessageBoxTask(order_, 2, is_reentrant_));
    target_->PostTask(FROM_HERE,
                      new RecursiveTask(2, order_, 3, is_reentrant_));
    // The trick here is that for recursive task processing, this task will be
    // ran _inside_ the MessageBox message loop, dismissing the MessageBox
    // without a chance.
    // For non-recursive task processing, this will be executed _after_ the
    // MessageBox will have been dismissed by the code below, where
    // expect_window_ is true.
    target_->PostTask(FROM_HERE, new EndDialogTask(order_, 4));
    target_->PostTask(FROM_HERE, new QuitTask(order_, 5));

    // Enforce that every tasks are sent before starting to run the main thread
    // message loop.
    ASSERT_TRUE(SetEvent(event_));

    // Poll for the MessageBox. Don't do this at home! At the speed we do it,
    // you will never realize one MessageBox was shown.
    for (; expect_window_;) {
      HWND window = FindWindow(L"#32770", kMessageBoxTitle);
      if (window) {
        // Dismiss it.
        for (;;) {
          HWND button = FindWindowEx(window, NULL, L"Button", NULL);
          if (button != NULL) {
            EXPECT_EQ(0, SendMessage(button, WM_LBUTTONDOWN, 0, 0));
            EXPECT_EQ(0, SendMessage(button, WM_LBUTTONUP, 0, 0));
            break;
          }
        }
        break;
      }
    }
  }

 private:
  MessageLoop* target_;
  HANDLE event_;
  TaskList* order_;
  bool expect_window_;
  bool is_reentrant_;
};

#endif  // defined(OS_WIN)

void RunTest_RecursiveDenial1(MessageLoop::Type message_loop_type) {
  MessageLoop loop(message_loop_type);

  EXPECT_TRUE(MessageLoop::current()->NestableTasksAllowed());
  TaskList order;
  MessageLoop::current()->PostTask(FROM_HERE,
                                   new RecursiveTask(2, &order, 1, false));
  MessageLoop::current()->PostTask(FROM_HERE,
                                   new RecursiveTask(2, &order, 2, false));
  MessageLoop::current()->PostTask(FROM_HERE, new QuitTask(&order, 3));

  MessageLoop::current()->Run();

  // FIFO order.
  ASSERT_EQ(14U, order.size());
  EXPECT_EQ(order[ 0], TaskItem(RECURSIVE, 1, true));
  EXPECT_EQ(order[ 1], TaskItem(RECURSIVE, 1, false));
  EXPECT_EQ(order[ 2], TaskItem(RECURSIVE, 2, true));
  EXPECT_EQ(order[ 3], TaskItem(RECURSIVE, 2, false));
  EXPECT_EQ(order[ 4], TaskItem(QUITMESSAGELOOP, 3, true));
  EXPECT_EQ(order[ 5], TaskItem(QUITMESSAGELOOP, 3, false));
  EXPECT_EQ(order[ 6], TaskItem(RECURSIVE, 1, true));
  EXPECT_EQ(order[ 7], TaskItem(RECURSIVE, 1, false));
  EXPECT_EQ(order[ 8], TaskItem(RECURSIVE, 2, true));
  EXPECT_EQ(order[ 9], TaskItem(RECURSIVE, 2, false));
  EXPECT_EQ(order[10], TaskItem(RECURSIVE, 1, true));
  EXPECT_EQ(order[11], TaskItem(RECURSIVE, 1, false));
  EXPECT_EQ(order[12], TaskItem(RECURSIVE, 2, true));
  EXPECT_EQ(order[13], TaskItem(RECURSIVE, 2, false));
}

void RunTest_RecursiveSupport1(MessageLoop::Type message_loop_type) {
  MessageLoop loop(message_loop_type);

  TaskList order;
  MessageLoop::current()->PostTask(FROM_HERE,
                                   new RecursiveTask(2, &order, 1, true));
  MessageLoop::current()->PostTask(FROM_HERE,
                                   new RecursiveTask(2, &order, 2, true));
  MessageLoop::current()->PostTask(FROM_HERE,
                                   new QuitTask(&order, 3));

  MessageLoop::current()->Run();

  // FIFO order.
  ASSERT_EQ(14U, order.size());
  EXPECT_EQ(order[ 0], TaskItem(RECURSIVE, 1, true));
  EXPECT_EQ(order[ 1], TaskItem(RECURSIVE, 1, false));
  EXPECT_EQ(order[ 2], TaskItem(RECURSIVE, 2, true));
  EXPECT_EQ(order[ 3], TaskItem(RECURSIVE, 2, false));
  EXPECT_EQ(order[ 4], TaskItem(QUITMESSAGELOOP, 3, true));
  EXPECT_EQ(order[ 5], TaskItem(QUITMESSAGELOOP, 3, false));
  EXPECT_EQ(order[ 6], TaskItem(RECURSIVE, 1, true));
  EXPECT_EQ(order[ 7], TaskItem(RECURSIVE, 1, false));
  EXPECT_EQ(order[ 8], TaskItem(RECURSIVE, 2, true));
  EXPECT_EQ(order[ 9], TaskItem(RECURSIVE, 2, false));
  EXPECT_EQ(order[10], TaskItem(RECURSIVE, 1, true));
  EXPECT_EQ(order[11], TaskItem(RECURSIVE, 1, false));
  EXPECT_EQ(order[12], TaskItem(RECURSIVE, 2, true));
  EXPECT_EQ(order[13], TaskItem(RECURSIVE, 2, false));
}

#if defined(OS_WIN)
// TODO(darin): These tests need to be ported since they test critical
// message loop functionality.

// A side effect of this test is the generation a beep. Sorry.
void RunTest_RecursiveDenial2(MessageLoop::Type message_loop_type) {
  MessageLoop loop(message_loop_type);

  Thread worker("RecursiveDenial2_worker");
  Thread::Options options;
  options.message_loop_type = message_loop_type;
  ASSERT_EQ(true, worker.StartWithOptions(options));
  TaskList order;
  ScopedHandle event(CreateEvent(NULL, FALSE, FALSE, NULL));
  worker.message_loop()->PostTask(FROM_HERE,
                                  new Recursive2Tasks(MessageLoop::current(),
                                                      event,
                                                      true,
                                                      &order,
                                                      false));
  // Let the other thread execute.
  WaitForSingleObject(event, INFINITE);
  MessageLoop::current()->Run();

  ASSERT_EQ(order.size(), 17);
  EXPECT_EQ(order[ 0], TaskItem(RECURSIVE, 1, true));
  EXPECT_EQ(order[ 1], TaskItem(RECURSIVE, 1, false));
  EXPECT_EQ(order[ 2], TaskItem(MESSAGEBOX, 2, true));
  EXPECT_EQ(order[ 3], TaskItem(MESSAGEBOX, 2, false));
  EXPECT_EQ(order[ 4], TaskItem(RECURSIVE, 3, true));
  EXPECT_EQ(order[ 5], TaskItem(RECURSIVE, 3, false));
  // When EndDialogTask is processed, the window is already dismissed, hence no
  // "end" entry.
  EXPECT_EQ(order[ 6], TaskItem(ENDDIALOG, 4, true));
  EXPECT_EQ(order[ 7], TaskItem(QUITMESSAGELOOP, 5, true));
  EXPECT_EQ(order[ 8], TaskItem(QUITMESSAGELOOP, 5, false));
  EXPECT_EQ(order[ 9], TaskItem(RECURSIVE, 1, true));
  EXPECT_EQ(order[10], TaskItem(RECURSIVE, 1, false));
  EXPECT_EQ(order[11], TaskItem(RECURSIVE, 3, true));
  EXPECT_EQ(order[12], TaskItem(RECURSIVE, 3, false));
  EXPECT_EQ(order[13], TaskItem(RECURSIVE, 1, true));
  EXPECT_EQ(order[14], TaskItem(RECURSIVE, 1, false));
  EXPECT_EQ(order[15], TaskItem(RECURSIVE, 3, true));
  EXPECT_EQ(order[16], TaskItem(RECURSIVE, 3, false));
}

// A side effect of this test is the generation a beep. Sorry.  This test also
// needs to process windows messages on the current thread.
void RunTest_RecursiveSupport2(MessageLoop::Type message_loop_type) {
  MessageLoop loop(message_loop_type);

  Thread worker("RecursiveSupport2_worker");
  Thread::Options options;
  options.message_loop_type = message_loop_type;
  ASSERT_EQ(true, worker.StartWithOptions(options));
  TaskList order;
  ScopedHandle event(CreateEvent(NULL, FALSE, FALSE, NULL));
  worker.message_loop()->PostTask(FROM_HERE,
                                  new Recursive2Tasks(MessageLoop::current(),
                                                      event,
                                                      false,
                                                      &order,
                                                      true));
  // Let the other thread execute.
  WaitForSingleObject(event, INFINITE);
  MessageLoop::current()->Run();

  ASSERT_EQ(order.size(), 18);
  EXPECT_EQ(order[ 0], TaskItem(RECURSIVE, 1, true));
  EXPECT_EQ(order[ 1], TaskItem(RECURSIVE, 1, false));
  EXPECT_EQ(order[ 2], TaskItem(MESSAGEBOX, 2, true));
  // Note that this executes in the MessageBox modal loop.
  EXPECT_EQ(order[ 3], TaskItem(RECURSIVE, 3, true));
  EXPECT_EQ(order[ 4], TaskItem(RECURSIVE, 3, false));
  EXPECT_EQ(order[ 5], TaskItem(ENDDIALOG, 4, true));
  EXPECT_EQ(order[ 6], TaskItem(ENDDIALOG, 4, false));
  EXPECT_EQ(order[ 7], TaskItem(MESSAGEBOX, 2, false));
  /* The order can subtly change here. The reason is that when RecursiveTask(1)
     is called in the main thread, if it is faster than getting to the
     PostTask(FROM_HERE, QuitTask) execution, the order of task execution can
     change. We don't care anyway that the order isn't correct.
  EXPECT_EQ(order[ 8], TaskItem(QUITMESSAGELOOP, 5, true));
  EXPECT_EQ(order[ 9], TaskItem(QUITMESSAGELOOP, 5, false));
  EXPECT_EQ(order[10], TaskItem(RECURSIVE, 1, true));
  EXPECT_EQ(order[11], TaskItem(RECURSIVE, 1, false));
  */
  EXPECT_EQ(order[12], TaskItem(RECURSIVE, 3, true));
  EXPECT_EQ(order[13], TaskItem(RECURSIVE, 3, false));
  EXPECT_EQ(order[14], TaskItem(RECURSIVE, 1, true));
  EXPECT_EQ(order[15], TaskItem(RECURSIVE, 1, false));
  EXPECT_EQ(order[16], TaskItem(RECURSIVE, 3, true));
  EXPECT_EQ(order[17], TaskItem(RECURSIVE, 3, false));
}

#endif  // defined(OS_WIN)

class TaskThatPumps : public OrderedTasks {
 public:
  TaskThatPumps(TaskList* order, int cookie)
      : OrderedTasks(order, PUMPS, cookie) {
  }

  virtual void Run() {
    RunStart();
    bool old_state = MessageLoop::current()->NestableTasksAllowed();
    MessageLoop::current()->SetNestableTasksAllowed(true);
    MessageLoop::current()->RunAllPending();
    MessageLoop::current()->SetNestableTasksAllowed(old_state);
    RunEnd();
  }
};

// Tests that non nestable tasks run in FIFO if there are no nested loops.
void RunTest_NonNestableWithNoNesting(MessageLoop::Type message_loop_type) {
  MessageLoop loop(message_loop_type);

  TaskList order;

  Task* task = new OrderedTasks(&order, 1);
  MessageLoop::current()->PostNonNestableTask(FROM_HERE, task);
  MessageLoop::current()->PostTask(FROM_HERE, new OrderedTasks(&order, 2));
  MessageLoop::current()->PostTask(FROM_HERE, new QuitTask(&order, 3));
  MessageLoop::current()->Run();

  // FIFO order.
  ASSERT_EQ(6U, order.size());
  EXPECT_EQ(order[ 0], TaskItem(ORDERERD, 1, true));
  EXPECT_EQ(order[ 1], TaskItem(ORDERERD, 1, false));
  EXPECT_EQ(order[ 2], TaskItem(ORDERERD, 2, true));
  EXPECT_EQ(order[ 3], TaskItem(ORDERERD, 2, false));
  EXPECT_EQ(order[ 4], TaskItem(QUITMESSAGELOOP, 3, true));
  EXPECT_EQ(order[ 5], TaskItem(QUITMESSAGELOOP, 3, false));
}

// Tests that non nestable tasks don't run when there's code in the call stack.
void RunTest_NonNestableInNestedLoop(MessageLoop::Type message_loop_type,
                                     bool use_delayed) {
  MessageLoop loop(message_loop_type);

  TaskList order;

  MessageLoop::current()->PostTask(FROM_HERE,
                                   new TaskThatPumps(&order, 1));
  Task* task = new OrderedTasks(&order, 2);
  if (use_delayed) {
    MessageLoop::current()->PostNonNestableDelayedTask(FROM_HERE, task, 1);
  } else {
    MessageLoop::current()->PostNonNestableTask(FROM_HERE, task);
  }
  MessageLoop::current()->PostTask(FROM_HERE, new OrderedTasks(&order, 3));
  MessageLoop::current()->PostTask(FROM_HERE, new SleepTask(&order, 4, 50));
  MessageLoop::current()->PostTask(FROM_HERE, new OrderedTasks(&order, 5));
  Task* non_nestable_quit = new QuitTask(&order, 6);
  if (use_delayed) {
    MessageLoop::current()->PostNonNestableDelayedTask(FROM_HERE,
                                                       non_nestable_quit,
                                                       2);
  } else {
    MessageLoop::current()->PostNonNestableTask(FROM_HERE, non_nestable_quit);
  }

  MessageLoop::current()->Run();

  // FIFO order.
  ASSERT_EQ(12U, order.size());
  EXPECT_EQ(order[ 0], TaskItem(PUMPS, 1, true));
  EXPECT_EQ(order[ 1], TaskItem(ORDERERD, 3, true));
  EXPECT_EQ(order[ 2], TaskItem(ORDERERD, 3, false));
  EXPECT_EQ(order[ 3], TaskItem(SLEEP, 4, true));
  EXPECT_EQ(order[ 4], TaskItem(SLEEP, 4, false));
  EXPECT_EQ(order[ 5], TaskItem(ORDERERD, 5, true));
  EXPECT_EQ(order[ 6], TaskItem(ORDERERD, 5, false));
  EXPECT_EQ(order[ 7], TaskItem(PUMPS, 1, false));
  EXPECT_EQ(order[ 8], TaskItem(ORDERERD, 2, true));
  EXPECT_EQ(order[ 9], TaskItem(ORDERERD, 2, false));
  EXPECT_EQ(order[10], TaskItem(QUITMESSAGELOOP, 6, true));
  EXPECT_EQ(order[11], TaskItem(QUITMESSAGELOOP, 6, false));
}

#if defined(OS_WIN)

class DispatcherImpl : public MessageLoopForUI::Dispatcher {
 public:
  DispatcherImpl() : dispatch_count_(0) {}

  virtual bool Dispatch(const MSG& msg) {
    ::TranslateMessage(&msg);
    ::DispatchMessage(&msg);
    // Do not count WM_TIMER since it is not what we post and it will cause
    // flakiness.
    if (msg.message != WM_TIMER)
      ++dispatch_count_;
    // We treat WM_LBUTTONUP as the last message.
    return msg.message != WM_LBUTTONUP;
  }

  int dispatch_count_;
};

void RunTest_Dispatcher(MessageLoop::Type message_loop_type) {
  MessageLoop loop(message_loop_type);

  class MyTask : public Task {
  public:
    virtual void Run() {
      PostMessage(NULL, WM_LBUTTONDOWN, 0, 0);
      PostMessage(NULL, WM_LBUTTONUP, 'A', 0);
    }
  };
  Task* task = new MyTask();
  MessageLoop::current()->PostDelayedTask(FROM_HERE, task, 100);
  DispatcherImpl dispatcher;
  MessageLoopForUI::current()->Run(&dispatcher);
  ASSERT_EQ(2, dispatcher.dispatch_count_);
}

LRESULT CALLBACK MsgFilterProc(int code, WPARAM wparam, LPARAM lparam) {
  if (code == base::MessagePumpForUI::kMessageFilterCode) {
    MSG* msg = reinterpret_cast<MSG*>(lparam);
    if (msg->message == WM_LBUTTONDOWN)
      return TRUE;
  }
  return FALSE;
}

void RunTest_DispatcherWithMessageHook(MessageLoop::Type message_loop_type) {
  MessageLoop loop(message_loop_type);

  class MyTask : public Task {
  public:
    virtual void Run() {
      PostMessage(NULL, WM_LBUTTONDOWN, 0, 0);
      PostMessage(NULL, WM_LBUTTONUP, 'A', 0);
    }
  };
  Task* task = new MyTask();
  MessageLoop::current()->PostDelayedTask(FROM_HERE, task, 100);
  HHOOK msg_hook = SetWindowsHookEx(WH_MSGFILTER,
                                    MsgFilterProc,
                                    NULL,
                                    GetCurrentThreadId());
  DispatcherImpl dispatcher;
  MessageLoopForUI::current()->Run(&dispatcher);
  ASSERT_EQ(1, dispatcher.dispatch_count_);
  UnhookWindowsHookEx(msg_hook);
}

class TestIOHandler : public MessageLoopForIO::IOHandler {
 public:
  TestIOHandler(const wchar_t* name, HANDLE signal, bool wait);

  virtual void OnIOCompleted(MessageLoopForIO::IOContext* context,
                             DWORD bytes_transfered, DWORD error);

  void Init();
  void WaitForIO();
  OVERLAPPED* context() { return &context_.overlapped; }
  DWORD size() { return sizeof(buffer_); }

 private:
  char buffer_[48];
  MessageLoopForIO::IOContext context_;
  HANDLE signal_;
  ScopedHandle file_;
  bool wait_;
};

TestIOHandler::TestIOHandler(const wchar_t* name, HANDLE signal, bool wait)
    : signal_(signal), wait_(wait) {
  memset(buffer_, 0, sizeof(buffer_));
  memset(&context_, 0, sizeof(context_));
  context_.handler = this;

  file_.Set(CreateFile(name, GENERIC_READ, 0, NULL, OPEN_EXISTING,
                       FILE_FLAG_OVERLAPPED, NULL));
  EXPECT_TRUE(file_.IsValid());
}

void TestIOHandler::Init() {
  MessageLoopForIO::current()->RegisterIOHandler(file_, this);

  DWORD read;
  EXPECT_FALSE(ReadFile(file_, buffer_, size(), &read, context()));
  EXPECT_EQ(ERROR_IO_PENDING, GetLastError());
  if (wait_)
    WaitForIO();
}

void TestIOHandler::OnIOCompleted(MessageLoopForIO::IOContext* context,
                                  DWORD bytes_transfered, DWORD error) {
  ASSERT_TRUE(context == &context_);
  ASSERT_TRUE(SetEvent(signal_));
}

void TestIOHandler::WaitForIO() {
  EXPECT_TRUE(MessageLoopForIO::current()->WaitForIOCompletion(300, this));
  EXPECT_TRUE(MessageLoopForIO::current()->WaitForIOCompletion(400, this));
}

class IOHandlerTask : public Task {
 public:
  explicit IOHandlerTask(TestIOHandler* handler) : handler_(handler) {}
  virtual void Run() {
    handler_->Init();
  }

 private:
  TestIOHandler* handler_;
};

void RunTest_IOHandler() {
  ScopedHandle callback_called(CreateEvent(NULL, TRUE, FALSE, NULL));
  ASSERT_TRUE(callback_called.IsValid());

  const wchar_t* kPipeName = L"\\\\.\\pipe\\iohandler_pipe";
  ScopedHandle server(CreateNamedPipe(kPipeName, PIPE_ACCESS_OUTBOUND, 0, 1,
                                      0, 0, 0, NULL));
  ASSERT_TRUE(server.IsValid());

  Thread thread("IOHandler test");
  Thread::Options options;
  options.message_loop_type = MessageLoop::TYPE_IO;
  ASSERT_TRUE(thread.StartWithOptions(options));

  MessageLoop* thread_loop = thread.message_loop();
  ASSERT_TRUE(NULL != thread_loop);

  TestIOHandler handler(kPipeName, callback_called, false);
  IOHandlerTask* task = new IOHandlerTask(&handler);
  thread_loop->PostTask(FROM_HERE, task);
  Sleep(100);  // Make sure the thread runs and sleeps for lack of work.

  const char buffer[] = "Hello there!";
  DWORD written;
  EXPECT_TRUE(WriteFile(server, buffer, sizeof(buffer), &written, NULL));

  DWORD result = WaitForSingleObject(callback_called, 1000);
  EXPECT_EQ(WAIT_OBJECT_0, result);

  thread.Stop();
}

void RunTest_WaitForIO() {
  ScopedHandle callback1_called(CreateEvent(NULL, TRUE, FALSE, NULL));
  ScopedHandle callback2_called(CreateEvent(NULL, TRUE, FALSE, NULL));
  ASSERT_TRUE(callback1_called.IsValid());
  ASSERT_TRUE(callback2_called.IsValid());

  const wchar_t* kPipeName1 = L"\\\\.\\pipe\\iohandler_pipe1";
  const wchar_t* kPipeName2 = L"\\\\.\\pipe\\iohandler_pipe2";
  ScopedHandle server1(CreateNamedPipe(kPipeName1, PIPE_ACCESS_OUTBOUND, 0, 1,
                                       0, 0, 0, NULL));
  ScopedHandle server2(CreateNamedPipe(kPipeName2, PIPE_ACCESS_OUTBOUND, 0, 1,
                                       0, 0, 0, NULL));
  ASSERT_TRUE(server1.IsValid());
  ASSERT_TRUE(server2.IsValid());

  Thread thread("IOHandler test");
  Thread::Options options;
  options.message_loop_type = MessageLoop::TYPE_IO;
  ASSERT_TRUE(thread.StartWithOptions(options));

  MessageLoop* thread_loop = thread.message_loop();
  ASSERT_TRUE(NULL != thread_loop);

  TestIOHandler handler1(kPipeName1, callback1_called, false);
  TestIOHandler handler2(kPipeName2, callback2_called, true);
  IOHandlerTask* task1 = new IOHandlerTask(&handler1);
  IOHandlerTask* task2 = new IOHandlerTask(&handler2);
  thread_loop->PostTask(FROM_HERE, task1);
  Sleep(100);  // Make sure the thread runs and sleeps for lack of work.
  thread_loop->PostTask(FROM_HERE, task2);
  Sleep(100);

  // At this time handler1 is waiting to be called, and the thread is waiting
  // on the Init method of handler2, filtering only handler2 callbacks.

  const char buffer[] = "Hello there!";
  DWORD written;
  EXPECT_TRUE(WriteFile(server1, buffer, sizeof(buffer), &written, NULL));
  Sleep(200);
  EXPECT_EQ(WAIT_TIMEOUT, WaitForSingleObject(callback1_called, 0)) <<
      "handler1 has not been called";

  EXPECT_TRUE(WriteFile(server2, buffer, sizeof(buffer), &written, NULL));

  HANDLE objects[2] = { callback1_called.Get(), callback2_called.Get() };
  DWORD result = WaitForMultipleObjects(2, objects, TRUE, 1000);
  EXPECT_EQ(WAIT_OBJECT_0, result);

  thread.Stop();
}

#endif  // defined(OS_WIN)

}  // namespace

//-----------------------------------------------------------------------------
// Each test is run against each type of MessageLoop.  That way we are sure
// that message loops work properly in all configurations.  Of course, in some
// cases, a unit test may only be for a particular type of loop.

TEST(MessageLoopTest, PostTask) {
  RunTest_PostTask(MessageLoop::TYPE_DEFAULT);
  RunTest_PostTask(MessageLoop::TYPE_UI);
  RunTest_PostTask(MessageLoop::TYPE_IO);
}

TEST(MessageLoopTest, PostTask_SEH) {
  RunTest_PostTask_SEH(MessageLoop::TYPE_DEFAULT);
  RunTest_PostTask_SEH(MessageLoop::TYPE_UI);
  RunTest_PostTask_SEH(MessageLoop::TYPE_IO);
}

TEST(MessageLoopTest, PostDelayedTask_Basic) {
  RunTest_PostDelayedTask_Basic(MessageLoop::TYPE_DEFAULT);
  RunTest_PostDelayedTask_Basic(MessageLoop::TYPE_UI);
  RunTest_PostDelayedTask_Basic(MessageLoop::TYPE_IO);
}

TEST(MessageLoopTest, PostDelayedTask_InDelayOrder) {
  RunTest_PostDelayedTask_InDelayOrder(MessageLoop::TYPE_DEFAULT);
  RunTest_PostDelayedTask_InDelayOrder(MessageLoop::TYPE_UI);
  RunTest_PostDelayedTask_InDelayOrder(MessageLoop::TYPE_IO);
}

TEST(MessageLoopTest, PostDelayedTask_InPostOrder) {
  RunTest_PostDelayedTask_InPostOrder(MessageLoop::TYPE_DEFAULT);
  RunTest_PostDelayedTask_InPostOrder(MessageLoop::TYPE_UI);
  RunTest_PostDelayedTask_InPostOrder(MessageLoop::TYPE_IO);
}

TEST(MessageLoopTest, PostDelayedTask_InPostOrder_2) {
  RunTest_PostDelayedTask_InPostOrder_2(MessageLoop::TYPE_DEFAULT);
  RunTest_PostDelayedTask_InPostOrder_2(MessageLoop::TYPE_UI);
  RunTest_PostDelayedTask_InPostOrder_2(MessageLoop::TYPE_IO);
}

TEST(MessageLoopTest, PostDelayedTask_InPostOrder_3) {
  RunTest_PostDelayedTask_InPostOrder_3(MessageLoop::TYPE_DEFAULT);
  RunTest_PostDelayedTask_InPostOrder_3(MessageLoop::TYPE_UI);
  RunTest_PostDelayedTask_InPostOrder_3(MessageLoop::TYPE_IO);
}

TEST(MessageLoopTest, PostDelayedTask_SharedTimer) {
  RunTest_PostDelayedTask_SharedTimer(MessageLoop::TYPE_DEFAULT);
  RunTest_PostDelayedTask_SharedTimer(MessageLoop::TYPE_UI);
  RunTest_PostDelayedTask_SharedTimer(MessageLoop::TYPE_IO);
}

#if defined(OS_WIN)
TEST(MessageLoopTest, PostDelayedTask_SharedTimer_SubPump) {
  RunTest_PostDelayedTask_SharedTimer_SubPump();
}
#endif

// TODO(darin): MessageLoop does not support deleting all tasks in the
// destructor.
// Fails, http://crbug.com/50272.
TEST(MessageLoopTest, FAILS_EnsureTaskDeletion) {
  RunTest_EnsureTaskDeletion(MessageLoop::TYPE_DEFAULT);
  RunTest_EnsureTaskDeletion(MessageLoop::TYPE_UI);
  RunTest_EnsureTaskDeletion(MessageLoop::TYPE_IO);
}

// TODO(darin): MessageLoop does not support deleting all tasks in the
// destructor.
// Fails, http://crbug.com/50272.
TEST(MessageLoopTest, FAILS_EnsureTaskDeletion_Chain) {
  RunTest_EnsureTaskDeletion_Chain(MessageLoop::TYPE_DEFAULT);
  RunTest_EnsureTaskDeletion_Chain(MessageLoop::TYPE_UI);
  RunTest_EnsureTaskDeletion_Chain(MessageLoop::TYPE_IO);
}

#if defined(OS_WIN)
TEST(MessageLoopTest, Crasher) {
  RunTest_Crasher(MessageLoop::TYPE_DEFAULT);
  RunTest_Crasher(MessageLoop::TYPE_UI);
  RunTest_Crasher(MessageLoop::TYPE_IO);
}

TEST(MessageLoopTest, CrasherNasty) {
  RunTest_CrasherNasty(MessageLoop::TYPE_DEFAULT);
  RunTest_CrasherNasty(MessageLoop::TYPE_UI);
  RunTest_CrasherNasty(MessageLoop::TYPE_IO);
}
#endif  // defined(OS_WIN)

TEST(MessageLoopTest, Nesting) {
  RunTest_Nesting(MessageLoop::TYPE_DEFAULT);
  RunTest_Nesting(MessageLoop::TYPE_UI);
  RunTest_Nesting(MessageLoop::TYPE_IO);
}

TEST(MessageLoopTest, RecursiveDenial1) {
  RunTest_RecursiveDenial1(MessageLoop::TYPE_DEFAULT);
  RunTest_RecursiveDenial1(MessageLoop::TYPE_UI);
  RunTest_RecursiveDenial1(MessageLoop::TYPE_IO);
}

TEST(MessageLoopTest, RecursiveSupport1) {
  RunTest_RecursiveSupport1(MessageLoop::TYPE_DEFAULT);
  RunTest_RecursiveSupport1(MessageLoop::TYPE_UI);
  RunTest_RecursiveSupport1(MessageLoop::TYPE_IO);
}

#if defined(OS_WIN)
// This test occasionally hangs http://crbug.com/44567
TEST(MessageLoopTest, DISABLED_RecursiveDenial2) {
  RunTest_RecursiveDenial2(MessageLoop::TYPE_DEFAULT);
  RunTest_RecursiveDenial2(MessageLoop::TYPE_UI);
  RunTest_RecursiveDenial2(MessageLoop::TYPE_IO);
}

TEST(MessageLoopTest, RecursiveSupport2) {
  // This test requires a UI loop
  RunTest_RecursiveSupport2(MessageLoop::TYPE_UI);
}
#endif  // defined(OS_WIN)

TEST(MessageLoopTest, NonNestableWithNoNesting) {
  RunTest_NonNestableWithNoNesting(MessageLoop::TYPE_DEFAULT);
  RunTest_NonNestableWithNoNesting(MessageLoop::TYPE_UI);
  RunTest_NonNestableWithNoNesting(MessageLoop::TYPE_IO);
}

TEST(MessageLoopTest, NonNestableInNestedLoop) {
  RunTest_NonNestableInNestedLoop(MessageLoop::TYPE_DEFAULT, false);
  RunTest_NonNestableInNestedLoop(MessageLoop::TYPE_UI, false);
  RunTest_NonNestableInNestedLoop(MessageLoop::TYPE_IO, false);
}

TEST(MessageLoopTest, NonNestableDelayedInNestedLoop) {
  RunTest_NonNestableInNestedLoop(MessageLoop::TYPE_DEFAULT, true);
  RunTest_NonNestableInNestedLoop(MessageLoop::TYPE_UI, true);
  RunTest_NonNestableInNestedLoop(MessageLoop::TYPE_IO, true);
}

class DummyTask : public Task {
 public:
  explicit DummyTask(int num_tasks) : num_tasks_(num_tasks) {}

  virtual void Run() {
    if (num_tasks_ > 1) {
      MessageLoop::current()->PostTask(
          FROM_HERE,
          new DummyTask(num_tasks_ - 1));
    } else {
      MessageLoop::current()->Quit();
    }
  }

 private:
  const int num_tasks_;
};

class DummyTaskObserver : public MessageLoop::TaskObserver {
 public:
  explicit DummyTaskObserver(int num_tasks)
      : num_tasks_started_(0),
        num_tasks_processed_(0),
        num_tasks_(num_tasks) {}

  virtual ~DummyTaskObserver() {}

  virtual void WillProcessTask(const Task* task) {
    num_tasks_started_++;
    EXPECT_TRUE(task != NULL);
    EXPECT_LE(num_tasks_started_, num_tasks_);
    EXPECT_EQ(num_tasks_started_, num_tasks_processed_ + 1);
  }

  virtual void DidProcessTask(const Task* task) {
    num_tasks_processed_++;
    EXPECT_TRUE(task != NULL);
    EXPECT_LE(num_tasks_started_, num_tasks_);
    EXPECT_EQ(num_tasks_started_, num_tasks_processed_);
  }

  int num_tasks_started() const { return num_tasks_started_; }
  int num_tasks_processed() const { return num_tasks_processed_; }

 private:
  int num_tasks_started_;
  int num_tasks_processed_;
  const int num_tasks_;

  DISALLOW_COPY_AND_ASSIGN(DummyTaskObserver);
};

TEST(MessageLoopTest, TaskObserver) {
  const int kNumTasks = 6;
  DummyTaskObserver observer(kNumTasks);

  MessageLoop loop;
  loop.AddTaskObserver(&observer);
  loop.PostTask(FROM_HERE, new DummyTask(kNumTasks));
  loop.Run();
  loop.RemoveTaskObserver(&observer);

  EXPECT_EQ(kNumTasks, observer.num_tasks_started());
  EXPECT_EQ(kNumTasks, observer.num_tasks_processed());
}

#if defined(OS_WIN)
TEST(MessageLoopTest, Dispatcher) {
  // This test requires a UI loop
  RunTest_Dispatcher(MessageLoop::TYPE_UI);
}

TEST(MessageLoopTest, DispatcherWithMessageHook) {
  // This test requires a UI loop
  RunTest_DispatcherWithMessageHook(MessageLoop::TYPE_UI);
}

TEST(MessageLoopTest, IOHandler) {
  RunTest_IOHandler();
}

TEST(MessageLoopTest, WaitForIO) {
  RunTest_WaitForIO();
}

TEST(MessageLoopTest, HighResolutionTimer) {
  MessageLoop loop;

  const int kFastTimerMs = 5;
  const int kSlowTimerMs = 100;

  EXPECT_EQ(false, loop.high_resolution_timers_enabled());

  // Post a fast task to enable the high resolution timers.
  loop.PostDelayedTask(FROM_HERE, new DummyTask(1), kFastTimerMs);
  loop.Run();
  EXPECT_EQ(true, loop.high_resolution_timers_enabled());

  // Post a slow task and verify high resolution timers
  // are still enabled.
  loop.PostDelayedTask(FROM_HERE, new DummyTask(1), kSlowTimerMs);
  loop.Run();
  EXPECT_EQ(true, loop.high_resolution_timers_enabled());

  // Wait for a while so that high-resolution mode elapses.
  Sleep(MessageLoop::kHighResolutionTimerModeLeaseTimeMs);

  // Post a slow task to disable the high resolution timers.
  loop.PostDelayedTask(FROM_HERE, new DummyTask(1), kSlowTimerMs);
  loop.Run();
  EXPECT_EQ(false, loop.high_resolution_timers_enabled());
}

#endif  // defined(OS_WIN)

#if defined(OS_POSIX)

namespace {

class QuitDelegate : public base::MessagePumpLibevent::Watcher {
 public:
  virtual void OnFileCanWriteWithoutBlocking(int fd) {
    MessageLoop::current()->Quit();
  }
  virtual void OnFileCanReadWithoutBlocking(int fd) {
    MessageLoop::current()->Quit();
  }
};

TEST(MessageLoopTest, FileDescriptorWatcherOutlivesMessageLoop) {
  // Simulate a MessageLoop that dies before an FileDescriptorWatcher.
  // This could happen when people use the Singleton pattern or atexit.

  // Create a file descriptor.  Doesn't need to be readable or writable,
  // as we don't need to actually get any notifications.
  // pipe() is just the easiest way to do it.
  int pipefds[2];
  int err = pipe(pipefds);
  ASSERT_EQ(0, err);
  int fd = pipefds[1];
  {
    // Arrange for controller to live longer than message loop.
    base::MessagePumpLibevent::FileDescriptorWatcher controller;
    {
      MessageLoopForIO message_loop;

      QuitDelegate delegate;
      message_loop.WatchFileDescriptor(fd,
          true, MessageLoopForIO::WATCH_WRITE, &controller, &delegate);
      // and don't run the message loop, just destroy it.
    }
  }
  if (HANDLE_EINTR(close(pipefds[0])) < 0)
    PLOG(ERROR) << "close";
  if (HANDLE_EINTR(close(pipefds[1])) < 0)
    PLOG(ERROR) << "close";
}

TEST(MessageLoopTest, FileDescriptorWatcherDoubleStop) {
  // Verify that it's ok to call StopWatchingFileDescriptor().
  // (Errors only showed up in valgrind.)
  int pipefds[2];
  int err = pipe(pipefds);
  ASSERT_EQ(0, err);
  int fd = pipefds[1];
  {
    // Arrange for message loop to live longer than controller.
    MessageLoopForIO message_loop;
    {
      base::MessagePumpLibevent::FileDescriptorWatcher controller;

      QuitDelegate delegate;
      message_loop.WatchFileDescriptor(fd,
          true, MessageLoopForIO::WATCH_WRITE, &controller, &delegate);
      controller.StopWatchingFileDescriptor();
    }
  }
  if (HANDLE_EINTR(close(pipefds[0])) < 0)
    PLOG(ERROR) << "close";
  if (HANDLE_EINTR(close(pipefds[1])) < 0)
    PLOG(ERROR) << "close";
}

}  // namespace

#endif  // defined(OS_POSIX)

namespace {
class RunAtDestructionTask : public Task {
 public:
  RunAtDestructionTask(bool* task_destroyed, bool* destruction_observer_called)
      : task_destroyed_(task_destroyed),
        destruction_observer_called_(destruction_observer_called) {
  }
  ~RunAtDestructionTask() {
    EXPECT_FALSE(*destruction_observer_called_);
    *task_destroyed_ = true;
  }
  virtual void Run() {
    // This task should never run.
    ADD_FAILURE();
  }
 private:
  bool* task_destroyed_;
  bool* destruction_observer_called_;
};

class MLDestructionObserver : public MessageLoop::DestructionObserver {
 public:
  MLDestructionObserver(bool* task_destroyed, bool* destruction_observer_called)
      : task_destroyed_(task_destroyed),
        destruction_observer_called_(destruction_observer_called),
        task_destroyed_before_message_loop_(false) {
  }
  virtual void WillDestroyCurrentMessageLoop() {
    task_destroyed_before_message_loop_ = *task_destroyed_;
    *destruction_observer_called_ = true;
  }
  bool task_destroyed_before_message_loop() const {
    return task_destroyed_before_message_loop_;
  }
 private:
  bool* task_destroyed_;
  bool* destruction_observer_called_;
  bool task_destroyed_before_message_loop_;
};

}  // namespace

TEST(MessageLoopTest, DestructionObserverTest) {
  // Verify that the destruction observer gets called at the very end (after
  // all the pending tasks have been destroyed).
  MessageLoop* loop = new MessageLoop;
  const int kDelayMS = 100;

  bool task_destroyed = false;
  bool destruction_observer_called = false;

  MLDestructionObserver observer(&task_destroyed, &destruction_observer_called);
  loop->AddDestructionObserver(&observer);
  loop->PostDelayedTask(
      FROM_HERE,
      new RunAtDestructionTask(&task_destroyed, &destruction_observer_called),
      kDelayMS);
  delete loop;
  EXPECT_TRUE(observer.task_destroyed_before_message_loop());
  // The task should have been destroyed when we deleted the loop.
  EXPECT_TRUE(task_destroyed);
  EXPECT_TRUE(destruction_observer_called);
}