Jankometer: Generalize the code more. Add better support for monitoring IO thread.

base/message_pump_win.cc

 // 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 "base/message_pump_win.h"
 
 #include <math.h>
 
 #include "base/histogram.h"
 #include "base/win_util.h"
@@ skipping 479 matching lines @@
 
     if (ProcessInternalIOItem(item))
       return true;
   }
 
   if (item.context->handler) {
     if (filter && item.handler != filter) {
       // Save this item for later
       completed_io_.push_back(item);
     } else {
-      DCHECK(item.context->handler == item.handler);
+      DCHECK_EQ(item.context->handler, item.handler);
+      WillProcessIOEvent();
       item.handler->OnIOCompleted(item.context, item.bytes_transfered,
                                   item.error);
+      DidProcessIOEvent();
     }
   } else {
     // The handler must be gone by now, just cleanup the mess.
     delete item.context;
   }
   return true;
 }
 
 // Asks the OS for another IO completion result.
 bool MessagePumpForIO::GetIOItem(DWORD timeout, IOItem* item) {
@@ skipping 31 matching lines @@
        it != completed_io_.end(); ++it) {
     if (!filter || it->handler == filter) {
       *item = *it;
       completed_io_.erase(it);
       return true;
     }
   }
   return false;
 }
 
+void MessagePumpForIO::AddIOObserver(IOObserver *obs) {
+  io_observers_.AddObserver(obs);
+}
+
+void MessagePumpForIO::RemoveIOObserver(IOObserver *obs) {
+  io_observers_.RemoveObserver(obs);
+}
+
+void MessagePumpForIO::WillProcessIOEvent() {
+  FOR_EACH_OBSERVER(IOObserver, io_observers_, WillProcessIOEvent());
+}
+
+void MessagePumpForIO::DidProcessIOEvent() {
+  FOR_EACH_OBSERVER(IOObserver, io_observers_, DidProcessIOEvent());
+}
+
 }  // namespace base