Switch MessagePumpWin to use base::win::MessageWindow

base/message_loop/message_pump_win.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 "base/message_loop/message_pump_win.h"
 
 #include <math.h>
 #include <stdint.h>
 
 #include <limits>
@@ skipping 13 matching lines @@
 enum MessageLoopProblems {
   MESSAGE_POST_ERROR,
   COMPLETION_POST_ERROR,
   SET_TIMER_ERROR,
   RECEIVED_WM_QUIT_ERROR,
   MESSAGE_LOOP_PROBLEM_MAX,
 };
 
 }  // namespace
 
-static const wchar_t kWndClassFormat[] = L"Chrome_MessagePumpWindow_%p";
-
 // Message sent to get an additional time slice for pumping (processing) another
 // task (a series of such messages creates a continuous task pump).
 static const int kMsgHaveWork = WM_USER + 1;
 
 // The application-defined code passed to the hook procedure.
 static const int kMessageFilterCode = 0x5001;
 
 //-----------------------------------------------------------------------------
 // MessagePumpWin public:
 
-MessagePumpWin::MessagePumpWin() {
-}
+MessagePumpWin::MessagePumpWin() = default;
 
 void MessagePumpWin::Run(Delegate* delegate) {
   RunState s;
   s.delegate = delegate;
   s.should_quit = false;
   s.run_depth = state_ ? state_->run_depth + 1 : 1;
 
   // TODO(stanisc): crbug.com/596190: Remove this code once the bug is fixed.
   s.schedule_work_error_count = 0;
   s.last_schedule_work_error_time = Time();
@@ skipping 29 matching lines @@
   // "overflowingly" large, that means a delayed task was posted with a
   // super-long delay.
   return timeout < 0 ? 0 :
       (timeout > std::numeric_limits<int>::max() ?
        std::numeric_limits<int>::max() : static_cast<int>(timeout));
 }
 
 //-----------------------------------------------------------------------------
 // MessagePumpForUI public:
 
-MessagePumpForUI::MessagePumpForUI()
-    : atom_(0) {
-  InitMessageWnd();
+MessagePumpForUI::MessagePumpForUI() {
+  bool succeeded = message_window_.Create(
+      Bind(&MessagePumpForUI::MessageCallback, Unretained(this)));
+  DCHECK(succeeded);
 }
 
-MessagePumpForUI::~MessagePumpForUI() {
-  DestroyWindow(message_hwnd_);
-  UnregisterClass(MAKEINTATOM(atom_), CURRENT_MODULE());
-}
+MessagePumpForUI::~MessagePumpForUI() = default;
 
 void MessagePumpForUI::ScheduleWork() {
   if (InterlockedExchange(&work_state_, HAVE_WORK) != READY)
     return;  // Someone else continued the pumping.
 
   // Make sure the MessagePump does some work for us.
-  BOOL ret = PostMessage(message_hwnd_, kMsgHaveWork,
-                         reinterpret_cast<WPARAM>(this), 0);
+  BOOL ret = PostMessage(message_window_.hwnd(), kMsgHaveWork, 0, 0);
   if (ret)
     return;  // There was room in the Window Message queue.
 
   // We have failed to insert a have-work message, so there is a chance that we
   // will starve tasks/timers while sitting in a nested message loop.  Nested
   // loops only look at Windows Message queues, and don't look at *our* task
   // queues, etc., so we might not get a time slice in such. :-(
   // We could abort here, but the fear is that this failure mode is plausibly
   // common (queue is full, of about 2000 messages), so we'll do a near-graceful
   // recovery.  Nested loops are pretty transient (we think), so this will
   // probably be recoverable.
 
   // Clarify that we didn't really insert.
   InterlockedExchange(&work_state_, READY);
   UMA_HISTOGRAM_ENUMERATION("Chrome.MessageLoopProblem", MESSAGE_POST_ERROR,
                             MESSAGE_LOOP_PROBLEM_MAX);
   state_->schedule_work_error_count++;
   state_->last_schedule_work_error_time = Time::Now();
 }
 
 void MessagePumpForUI::ScheduleDelayedWork(const TimeTicks& delayed_work_time) {
   delayed_work_time_ = delayed_work_time;
   RescheduleTimer();
 }
 
 //-----------------------------------------------------------------------------
 // MessagePumpForUI private:
 
-// static
-LRESULT CALLBACK MessagePumpForUI::WndProcThunk(
-    HWND hwnd, UINT message, WPARAM wparam, LPARAM lparam) {
+bool MessagePumpForUI::MessageCallback(
+    UINT message, WPARAM wparam, LPARAM lparam, LRESULT* result) {
   switch (message) {
     case kMsgHaveWork:
-      reinterpret_cast<MessagePumpForUI*>(wparam)->HandleWorkMessage();
+      HandleWorkMessage();
       break;
     case WM_TIMER:
-      reinterpret_cast<MessagePumpForUI*>(wparam)->HandleTimerMessage();
+      HandleTimerMessage();
       break;
   }
-  return DefWindowProc(hwnd, message, wparam, lparam);
+  return false;
 }
 
 void MessagePumpForUI::DoRunLoop() {
   // IF this was just a simple PeekMessage() loop (servicing all possible work
   // queues), then Windows would try to achieve the following order according
   // to MSDN documentation about PeekMessage with no filter):
   //    * Sent messages
   //    * Posted messages
   //    * Sent messages (again)
   //    * WM_PAINT messages
@@ skipping 20 matching lines @@
     if (state_->should_quit)
       break;
 
     more_work_is_plausible |=
         state_->delegate->DoDelayedWork(&delayed_work_time_);
     // If we did not process any delayed work, then we can assume that our
     // existing WM_TIMER if any will fire when delayed work should run.  We
     // don't want to disturb that timer if it is already in flight.  However,
     // if we did do all remaining delayed work, then lets kill the WM_TIMER.
     if (more_work_is_plausible && delayed_work_time_.is_null())
-      KillTimer(message_hwnd_, reinterpret_cast<UINT_PTR>(this));
+      KillTimer(message_window_.hwnd(), reinterpret_cast<UINT_PTR>(this));
     if (state_->should_quit)
       break;
 
     if (more_work_is_plausible)
       continue;
 
     more_work_is_plausible = state_->delegate->DoIdleWork();
     if (state_->should_quit)
       break;
 
     if (more_work_is_plausible)
       continue;
 
     WaitForWork();  // Wait (sleep) until we have work to do again.
   }
 }
 
-void MessagePumpForUI::InitMessageWnd() {
-  // Generate a unique window class name.
-  string16 class_name = StringPrintf(kWndClassFormat, this);
-
-  HINSTANCE instance = CURRENT_MODULE();
-  WNDCLASSEX wc = {0};
-  wc.cbSize = sizeof(wc);
-  wc.lpfnWndProc = base::win::WrappedWindowProc<WndProcThunk>;
-  wc.hInstance = instance;
-  wc.lpszClassName = class_name.c_str();
-  atom_ = RegisterClassEx(&wc);
-  DCHECK(atom_);
-
-  message_hwnd_ = CreateWindowEx(0, MAKEINTATOM(atom_), 0, 0, 0, 0, 0, 0,
-                                 HWND_MESSAGE, 0, instance, 0);
-  DCHECK(message_hwnd_);
-}
-
 void MessagePumpForUI::WaitForWork() {
   // Wait until a message is available, up to the time needed by the timer
   // manager to fire the next set of timers.
   int delay;
   DWORD wait_flags = MWMO_INPUTAVAILABLE;
 
   while ((delay = GetCurrentDelay()) != 0) {
     if (delay < 0)  // Negative value means no timers waiting.
       delay = INFINITE;
 
@@ skipping 49 matching lines @@
 
   // Now give the delegate a chance to do some work.  It'll let us know if it
   // needs to do more work.
   if (state_->delegate->DoWork())
     ScheduleWork();
   state_->delegate->DoDelayedWork(&delayed_work_time_);
   RescheduleTimer();
 }
 
 void MessagePumpForUI::HandleTimerMessage() {
-  KillTimer(message_hwnd_, reinterpret_cast<UINT_PTR>(this));
+  KillTimer(message_window_.hwnd(), reinterpret_cast<UINT_PTR>(this));
 
   // If we are being called outside of the context of Run, then don't do
   // anything.  This could correspond to a MessageBox call or something of
   // that sort.
   if (!state_)
     return;
 
   state_->delegate->DoDelayedWork(&delayed_work_time_);
   RescheduleTimer();
 }
@@ skipping 24 matching lines @@
   int delay_msec = GetCurrentDelay();
   DCHECK_GE(delay_msec, 0);
   if (delay_msec == 0) {
     ScheduleWork();
   } else {
     if (delay_msec < USER_TIMER_MINIMUM)
       delay_msec = USER_TIMER_MINIMUM;
 
     // Create a WM_TIMER event that will wake us up to check for any pending
     // timers (in case we are running within a nested, external sub-pump).
-    BOOL ret = SetTimer(message_hwnd_, reinterpret_cast<UINT_PTR>(this),
-                        delay_msec, nullptr);
+    BOOL ret = SetTimer(message_window_.hwnd(), 0, delay_msec, nullptr);
     if (ret)
       return;
     // If we can't set timers, we are in big trouble... but cross our fingers
     // for now.
     // TODO(jar): If we don't see this error, use a CHECK() here instead.
     UMA_HISTOGRAM_ENUMERATION("Chrome.MessageLoopProblem", SET_TIMER_ERROR,
                               MESSAGE_LOOP_PROBLEM_MAX);
   }
 }
 
@@ skipping 22 matching lines @@
     UMA_HISTOGRAM_ENUMERATION("Chrome.MessageLoopProblem",
                               RECEIVED_WM_QUIT_ERROR, MESSAGE_LOOP_PROBLEM_MAX);
     // Repost the QUIT message so that it will be retrieved by the primary
     // GetMessage() loop.
     state_->should_quit = true;
     PostQuitMessage(static_cast<int>(msg.wParam));
     return false;
   }
 
   // While running our main message pump, we discard kMsgHaveWork messages.
-  if (msg.message == kMsgHaveWork && msg.hwnd == message_hwnd_)
+  if (msg.message == kMsgHaveWork && msg.hwnd == message_window_.hwnd())
     return ProcessPumpReplacementMessage();
 
   if (CallMsgFilter(const_cast<MSG*>(&msg), kMessageFilterCode))
     return true;
 
   TranslateMessage(&msg);
   DispatchMessage(&msg);
 
   return true;
 }
 
 bool MessagePumpForUI::ProcessPumpReplacementMessage() {
   // When we encounter a kMsgHaveWork message, this method is called to peek and
   // process a replacement message. The goal is to make the kMsgHaveWork as non-
   // intrusive as possible, even though a continuous stream of such messages are
   // posted. This method carefully peeks a message while there is no chance for
   // a kMsgHaveWork to be pending, then resets the |have_work_| flag (allowing a
   // replacement kMsgHaveWork to possibly be posted), and finally dispatches
   // that peeked replacement. Note that the re-post of kMsgHaveWork may be
   // asynchronous to this thread!!
 
   MSG msg;
   const bool have_message =
       PeekMessage(&msg, nullptr, 0, 0, PM_REMOVE) != FALSE;
 
   // Expect no message or a message different than kMsgHaveWork.
   DCHECK(!have_message || kMsgHaveWork != msg.message ||
-         msg.hwnd != message_hwnd_);
+         msg.hwnd != message_window_.hwnd());
 
   // Since we discarded a kMsgHaveWork message, we must update the flag.
   int old_work_state_ = InterlockedExchange(&work_state_, READY);
   DCHECK_EQ(HAVE_WORK, old_work_state_);
 
   // We don't need a special time slice if we didn't have_message to process.
   if (!have_message)
     return false;
 
   // Guarantee we'll get another time slice in the case where we go into native
   // windows code.   This ScheduleWork() may hurt performance a tiny bit when
   // tasks appear very infrequently, but when the event queue is busy, the
   // kMsgHaveWork events get (percentage wise) rarer and rarer.
   ScheduleWork();
   return ProcessMessageHelper(msg);
 }
 
 //-----------------------------------------------------------------------------
 // MessagePumpForGpu public:
 
 MessagePumpForGpu::MessagePumpForGpu() {
   event_.Set(CreateEvent(nullptr, FALSE, FALSE, nullptr));
 }
 
-MessagePumpForGpu::~MessagePumpForGpu() {}
+MessagePumpForGpu::~MessagePumpForGpu() = default;
 
 // static
 void MessagePumpForGpu::InitFactory() {
   bool init_result = MessageLoop::InitMessagePumpForUIFactory(
       &MessagePumpForGpu::CreateMessagePumpForGpu);
   DCHECK(init_result);
 }
 
 // static
 std::unique_ptr<MessagePump> MessagePumpForGpu::CreateMessagePumpForGpu() {
@@ skipping 290 matching lines @@
     if (!filter || it->handler == filter) {
       *item = *it;
       completed_io_.erase(it);
       return true;
     }
   }
   return false;
 }
 
 }  // namespace base