Replace PeekMessage for TSF awareness

base/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_pump_win.h"
 
 #include <math.h>
 
 #include "base/debug/trace_event.h"
 #include "base/message_loop.h"
 #include "base/metrics/histogram.h"
 #include "base/process_util.h"
 #include "base/win/wrapped_window_proc.h"
 
 namespace {
 
 enum MessageLoopProblems {
   MESSAGE_POST_ERROR,
   COMPLETION_POST_ERROR,
   SET_TIMER_ERROR,
   MESSAGE_LOOP_PROBLEM_MAX,
 };
 
+class SimpleMessageFilter : public base::MessagePumpForUI::MessageFilter {
+ public:
+  virtual ~SimpleMessageFilter() {}
+  virtual bool Init() OVERRIDE {
+    return true;
+  }
+  virtual BOOL DoPeekMessage(MSG* message,
+                             HWND window,
+                             UINT msg_filter_min,
+                             UINT msg_filter_max,
+                             UINT remove_msg) OVERRIDE {
+    return PeekMessage(message, window, msg_filter_min, msg_filter_max,
+                       remove_msg);
+  }
+  virtual bool ProcessMessage(const MSG& message) OVERRIDE {
+    return false;
+  }
+};
+
 }  // namespace
 
 namespace base {
 
 static const wchar_t kWndClass[] = L"Chrome_MessagePumpWindow";
 
 // 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;
 
@@ skipping 54 matching lines @@
   int delay = static_cast<int>(timeout);
   if (delay < 0)
     delay = 0;
 
   return delay;
 }
 
 //-----------------------------------------------------------------------------
 // MessagePumpForUI public:
 
-MessagePumpForUI::MessagePumpForUI() : instance_(NULL) {
+MessagePumpForUI::MessagePumpForUI()
+    : instance_(NULL),
+      message_filter_(new SimpleMessageFilter) {
+  DCHECK(message_filter_->Init());
+
   InitMessageWnd();
 }
 
 MessagePumpForUI::~MessagePumpForUI() {
   DestroyWindow(message_hwnd_);
   UnregisterClass(kWndClass, instance_);
 }
 
 void MessagePumpForUI::ScheduleWork() {
   if (InterlockedExchange(&have_work_, 1))
@@ skipping 65 matching lines @@
   if (!state_)
     return;
 
   // Create a mini-message-pump to force immediate processing of only Windows
   // WM_PAINT messages.  Don't provide an infinite loop, but do enough peeking
   // to get the job done.  Actual common max is 4 peeks, but we'll be a little
   // safe here.
   const int kMaxPeekCount = 20;
   int peek_count;
   for (peek_count = 0; peek_count < kMaxPeekCount; ++peek_count) {
-    MSG msg;
-    if (!PeekMessage(&msg, NULL, 0, 0, PM_REMOVE | PM_QS_PAINT))
+    MSG message;
+    if (!message_filter_->DoPeekMessage(&message, NULL, 0, 0,

[rvargas (doing something else), 2012/08/31 21:39:49]

This is also a candidate for not using the filter.

[yoichio, 2012/09/03 04:45:08]

Done.

+                                        PM_REMOVE | PM_QS_PAINT))
       break;
-    ProcessMessageHelper(msg);
+    ProcessMessageHelper(message);
     if (state_->should_quit)  // Handle WM_QUIT.
       break;
   }
   // Histogram what was really being used, to help to adjust kMaxPeekCount.
   DHISTOGRAM_COUNTS("Loop.PumpOutPendingPaintMessages Peeks", peek_count);
 }
 
 //-----------------------------------------------------------------------------
 // MessagePumpForUI private:
 
@@ skipping 90 matching lines @@
 
   DWORD result;
   result = MsgWaitForMultipleObjectsEx(0, NULL, delay, QS_ALLINPUT,
                                        MWMO_INPUTAVAILABLE);
 
   if (WAIT_OBJECT_0 == result) {
     // A WM_* message is available.
     // If a parent child relationship exists between windows across threads
     // then their thread inputs are implicitly attached.
     // This causes the MsgWaitForMultipleObjectsEx API to return indicating
-    // that messages are ready for processing (specifically mouse messages
-    // intended for the child window. Occurs if the child window has capture)
-    // The subsequent PeekMessages call fails to return any messages thus
+    // that messages are ready for processing (Specifically, mouse messages
+    // intended for the child window may appear if the child window has
+    // capture).
+    // The subsequent PeekMessages call may fail to return any messages thus
     // causing us to enter a tight loop at times.
     // The WaitMessage call below is a workaround to give the child window
-    // sometime to process its input messages.
+    // some time to process its input messages.
     MSG msg = {0};
     DWORD queue_status = GetQueueStatus(QS_MOUSE);
     if (HIWORD(queue_status) & QS_MOUSE &&
-       !PeekMessage(&msg, NULL, WM_MOUSEFIRST, WM_MOUSELAST, PM_NOREMOVE)) {
+        !message_filter_->DoPeekMessage(&msg, NULL, WM_MOUSEFIRST, WM_MOUSELAST,

[rvargas (doing something else), 2012/08/31 21:39:49]

I assume that TSF can generate mouse events... and that's why this is here

[yoichio, 2012/09/03 04:45:08]

Done.

+                                        PM_NOREMOVE)) {
       WaitMessage();
     }
     return;
   }
 
   DCHECK_NE(WAIT_FAILED, result) << GetLastError();
 }
 
 void MessagePumpForUI::HandleWorkMessage() {
   // If we are being called outside of the context of Run, then don't try to do
@@ skipping 36 matching lines @@
   // If there are sent messages in the queue then PeekMessage internally
   // dispatches the message and returns false. We return true in this
   // case to ensure that the message loop peeks again instead of calling
   // MsgWaitForMultipleObjectsEx again.
   bool sent_messages_in_queue = false;
   DWORD queue_status = GetQueueStatus(QS_SENDMESSAGE);
   if (HIWORD(queue_status) & QS_SENDMESSAGE)
     sent_messages_in_queue = true;
 
   MSG msg;
-  if (PeekMessage(&msg, NULL, 0, 0, PM_REMOVE))
+  if (message_filter_->DoPeekMessage(&msg, NULL, 0, 0, PM_REMOVE))
     return ProcessMessageHelper(msg);
 
   return sent_messages_in_queue;
 }
 
-bool MessagePumpForUI::ProcessMessageHelper(const MSG& msg) {
+bool MessagePumpForUI::ProcessMessageHelper(const MSG& message) {
   TRACE_EVENT1("base", "MessagePumpForUI::ProcessMessageHelper",
-               "message", msg.message);
-  if (WM_QUIT == msg.message) {
+               "message", message.message);
+  if (WM_QUIT == message.message) {
     // 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));
+    PostQuitMessage(static_cast<int>(message.wParam));
     return false;
   }
 
   // While running our main message pump, we discard kMsgHaveWork messages.
-  if (msg.message == kMsgHaveWork && msg.hwnd == message_hwnd_)
+  if (message.message == kMsgHaveWork && message.hwnd == message_hwnd_)
     return ProcessPumpReplacementMessage();
 
-  if (CallMsgFilter(const_cast<MSG*>(&msg), kMessageFilterCode))
+  if (CallMsgFilter(const_cast<MSG*>(&message), kMessageFilterCode))
     return true;
 
-  WillProcessMessage(msg);
+  WillProcessMessage(message);
 
-  if (state_->dispatcher) {
-    if (!state_->dispatcher->Dispatch(msg))
-      state_->should_quit = true;
-  } else {
-    TranslateMessage(&msg);
-    DispatchMessage(&msg);
+  if (!message_filter_->ProcessMessage(message)) {
+    if (state_->dispatcher) {
+      if (!state_->dispatcher->Dispatch(message))
+        state_->should_quit = true;
+    } else {
+      TranslateMessage(&message);
+      DispatchMessage(&message);
+    }
   }
 
-  DidProcessMessage(msg);
+  DidProcessMessage(message);
   return true;
 }
 
 bool MessagePumpForUI::ProcessPumpReplacementMessage() {
   // When we encounter a kMsgHaveWork message, this method is called to peek
   // and process a replacement message, such as a WM_PAINT or WM_TIMER.  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!!
 
   bool have_message = false;
-  MSG msg;
+  MSG message;
   // We should not process all window messages if we are in the context of an
   // OS modal loop, i.e. in the context of a windows API call like MessageBox.
   // This is to ensure that these messages are peeked out by the OS modal loop.
   if (MessageLoop::current()->os_modal_loop()) {
     // We only peek out WM_PAINT and WM_TIMER here for reasons mentioned above.
-    have_message = PeekMessage(&msg, NULL, WM_PAINT, WM_PAINT, PM_REMOVE) ||
-                   PeekMessage(&msg, NULL, WM_TIMER, WM_TIMER, PM_REMOVE);
+    have_message = PeekMessage(&message, NULL, WM_PAINT, WM_PAINT, PM_REMOVE) ||
+                   PeekMessage(&message, NULL, WM_TIMER, WM_TIMER, PM_REMOVE);
   } else {
-    have_message = (0 != PeekMessage(&msg, NULL, 0, 0, PM_REMOVE));
+    have_message = !!message_filter_->DoPeekMessage(&message, NULL, 0, 0,
+                                                    PM_REMOVE);
   }
 
-  DCHECK(!have_message || kMsgHaveWork != msg.message ||
-         msg.hwnd != message_hwnd_);
+  DCHECK(!have_message || kMsgHaveWork != message.message ||
+         message.hwnd != message_hwnd_);
 
   // Since we discarded a kMsgHaveWork message, we must update the flag.
   int old_have_work = InterlockedExchange(&have_work_, 0);
   DCHECK(old_have_work);
 
   // 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);
+  return ProcessMessageHelper(message);
+}
+
+void MessagePumpForUI::SetMessageFilter(MessageFilter *message_filter) {
+  message_filter_.reset(message_filter);
 }
 
 //-----------------------------------------------------------------------------
 // MessagePumpForIO public:
 
 MessagePumpForIO::MessagePumpForIO() {
   port_.Set(CreateIoCompletionPort(INVALID_HANDLE_VALUE, NULL, NULL, 1));
   DCHECK(port_.IsValid());
 }
 
@@ skipping 208 matching lines @@
 
 // static
 MessagePumpForIO::IOHandler* MessagePumpForIO::KeyToHandler(
     ULONG_PTR key,
     bool* has_valid_io_context) {
   *has_valid_io_context = ((key & 1) == 0);
   return reinterpret_cast<IOHandler*>(key & ~static_cast<ULONG_PTR>(1));
 }
 
 }  // namespace base