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diff --git a/ipc/chromium/src/base/message_pump_glib.h b/ipc/chromium/src/base/message_pump_glib.h
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+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+// Copyright (c) 2008 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.
+
+#ifndef BASE_MESSAGE_PUMP_GLIB_H_
+#define BASE_MESSAGE_PUMP_GLIB_H_
+
+#include "base/message_pump.h"
+#include "base/observer_list.h"
+#include "base/time.h"
+#include "mozilla/UniquePtr.h"
+#include "mozilla/Atomics.h"
+
+typedef union _GdkEvent GdkEvent;
+typedef struct _GMainContext GMainContext;
+typedef struct _GPollFD GPollFD;
+typedef struct _GSource GSource;
+
+namespace base {
+
+// This class implements a MessagePump needed for TYPE_UI MessageLoops on
+// OS_LINUX platforms using GLib.
+class MessagePumpForUI : public MessagePump {
+ public:
+  // Observer is notified prior to a GdkEvent event being dispatched. As
+  // Observers are notified of every change, they have to be FAST!
+  class Observer {
+   public:
+    virtual ~Observer() {}
+
+    // This method is called before processing a message.
+    virtual void WillProcessEvent(GdkEvent* event) = 0;
+
+    // This method is called after processing a message.
+    virtual void DidProcessEvent(GdkEvent* event) = 0;
+  };
+
+  // Dispatcher is used during a nested invocation of Run to dispatch events.
+  // If Run is invoked with a non-NULL Dispatcher, MessageLoop does not
+  // dispatch events (or invoke gtk_main_do_event), rather every event is
+  // passed to Dispatcher's Dispatch method for dispatch. It is up to the
+  // Dispatcher to dispatch, or not, the event.
+  //
+  // The nested loop is exited by either posting a quit, or returning false
+  // from Dispatch.
+  class Dispatcher {
+   public:
+    virtual ~Dispatcher() {}
+    // Dispatches the event. If true is returned processing continues as
+    // normal. If false is returned, the nested loop exits immediately.
+    virtual bool Dispatch(GdkEvent* event) = 0;
+  };
+
+  MessagePumpForUI();
+  virtual ~MessagePumpForUI();
+
+  // Like MessagePump::Run, but GdkEvent objects are routed through dispatcher.
+  virtual void RunWithDispatcher(Delegate* delegate, Dispatcher* dispatcher);
+
+  virtual void Run(Delegate* delegate) override {
+    RunWithDispatcher(delegate, NULL);
+  }
+  virtual void Quit() override;
+  virtual void ScheduleWork() override;
+  virtual void ScheduleDelayedWork(const TimeTicks& delayed_work_time) override;
+
+  // Internal methods used for processing the pump callbacks.  They are
+  // public for simplicity but should not be used directly.  HandlePrepare
+  // is called during the prepare step of glib, and returns a timeout that
+  // will be passed to the poll. HandleCheck is called after the poll
+  // has completed, and returns whether or not HandleDispatch should be called.
+  // HandleDispatch is called if HandleCheck returned true.
+  int HandlePrepare();
+  bool HandleCheck();
+  void HandleDispatch();
+
+  // Adds an Observer, which will start receiving notifications immediately.
+  void AddObserver(Observer* observer);
+
+  // Removes an Observer.  It is safe to call this method while an Observer is
+  // receiving a notification callback.
+  void RemoveObserver(Observer* observer);
+
+ private:
+  // We may make recursive calls to Run, so we save state that needs to be
+  // separate between them in this structure type.
+  struct RunState {
+    Delegate* delegate;
+    Dispatcher* dispatcher;
+
+    // Used to flag that the current Run() invocation should return ASAP.
+    bool should_quit;
+
+    // Used to count how many Run() invocations are on the stack.
+    int run_depth;
+
+    // This keeps the state of whether the pump got signaled that there was new
+    // work to be done. Since we eat the message on the wake up pipe as soon as
+    // we get it, we keep that state here to stay consistent.
+    bool has_work;
+  };
+
+  // Invoked from EventDispatcher. Notifies all observers we're about to
+  // process an event.
+  void WillProcessEvent(GdkEvent* event);
+
+  // Invoked from EventDispatcher. Notifies all observers we processed an
+  // event.
+  void DidProcessEvent(GdkEvent* event);
+
+  // Callback prior to gdk dispatching an event.
+  static void EventDispatcher(GdkEvent* event, void* data);
+
+  RunState* state_;
+
+  // This is a GLib structure that we can add event sources to.  We use the
+  // default GLib context, which is the one to which all GTK events are
+  // dispatched.
+  GMainContext* context_;
+
+  // This is the time when we need to do delayed work.
+  TimeTicks delayed_work_time_;
+
+  // The work source.  It is shared by all calls to Run and destroyed when
+  // the message pump is destroyed.
+  GSource* work_source_;
+
+  // We use a wakeup pipe to make sure we'll get out of the glib polling phase
+  // when another thread has scheduled us to do some work.  There is a glib
+  // mechanism g_main_context_wakeup, but this won't guarantee that our event's
+  // Dispatch() will be called.
+  int wakeup_pipe_read_;
+  int wakeup_pipe_write_;
+  // Use an autoptr to avoid needing the definition of GPollFD in the header.
+  mozilla::UniquePtr<GPollFD> wakeup_gpollfd_;
+
+  mozilla::Atomic<bool> pipe_full_;
+
+  // List of observers.
+  ObserverList<Observer> observers_;
+
+  DISALLOW_COPY_AND_ASSIGN(MessagePumpForUI);
+};
+
+}  // namespace base
+
+#endif  // BASE_MESSAGE_PUMP_GLIB_H_