Refactor the glib message-pump, and use it as the base for a gtk message pump and an X message pump.

The changes:
 * Rename MessagePumpGlibX to MessagePumpX.
 * Rename MessagePumpForUI to MessagePumpGlib.
 * Move some stuff out of MessagePumpGlib, and into MessagePumpGtk and MessagePumpX.
 * Rename MessagePumpForUI::Observer to MessageObserver, moved the platform-specific implementations into MessagePumpGtk and MessagePumpX. Ditto for MessagePumpForUI::Dispatcher.

MessagePumpX is independent of MessagePumpGtk. At the moment, MessagePumpX does process some GDK event, but once we have a complete native_widget_x, we can take out the GDK processing and things should continue to work.

BUG=none
TEST=existing message-pump tests.

Review URL: http://codereview.chromium.org/7250001

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@90418 0039d316-1c4b-4281-b951-d872f2087c98


CrOS-Libchrome-Original-Commit: 2047ef4d68229d47cba8bf7f2e0465ab31f8b3ce
diff --git a/base/base.gypi b/base/base.gypi
index dac1bd2..41ea923 100644
--- a/base/base.gypi
+++ b/base/base.gypi
@@ -368,9 +368,15 @@
               'sources!': [
                 'atomicops_internals_x86_gcc.cc',
                 'message_pump_glib.cc',
-                'message_pump_glib_x.cc',
+                'message_pump_gtk.cc',
+                'message_pump_x.cc',
               ],
           }],
+          [ 'touchui==0', {
+            'sources!' : [ 'message_pump_x.cc', ],
+          }, {
+            'sources!' : [ 'message_pump_gtk.cc', ],
+          }],
           [ 'OS != "linux"', {
               'sources!': [
                 # Not automatically excluded by the *linux.cc rules.
@@ -571,9 +577,10 @@
         'md5.h',
         'message_pump_glib.cc',
         'message_pump_glib.h',
-        'message_pump_glib_x.cc',
-        'message_pump_glib_x.h',
-        'message_pump_glib_x_dispatch.h',
+        'message_pump_gtk.cc',
+        'message_pump_gtk.h',
+        'message_pump_x.cc',
+        'message_pump_x.h',
         'message_pump_libevent.cc',
         'message_pump_libevent.h',
         'message_pump_mac.h',
diff --git a/base/message_loop.cc b/base/message_loop.cc
index b0526f4..e45c0d7 100644
--- a/base/message_loop.cc
+++ b/base/message_loop.cc
@@ -25,14 +25,16 @@
 #if defined(OS_POSIX)
 #include "base/message_pump_libevent.h"
 #endif
+
 #if defined(OS_POSIX) && !defined(OS_MACOSX)
 #include <gdk/gdk.h>
 #include <gdk/gdkx.h>
-#include "base/message_pump_glib.h"
-#endif
 #if defined(TOUCH_UI)
-#include "base/message_pump_glib_x.h"
-#endif
+#include "base/message_pump_x.h"
+#else
+#include "base/message_pump_gtk.h"
+#endif  // defined(TOUCH_UI)
+#endif  // defined(OS_POSIX) && !defined(OS_MACOSX)
 
 using base::TimeDelta;
 using base::TimeTicks;
@@ -176,7 +178,7 @@
 #define MESSAGE_PUMP_UI base::MessagePumpMac::Create()
 #define MESSAGE_PUMP_IO new base::MessagePumpLibevent()
 #elif defined(TOUCH_UI)
-#define MESSAGE_PUMP_UI new base::MessagePumpGlibX()
+#define MESSAGE_PUMP_UI new base::MessagePumpX()
 #define MESSAGE_PUMP_IO new base::MessagePumpLibevent()
 #elif defined(OS_NACL)
 // Currently NaCl doesn't have a UI or an IO MessageLoop.
@@ -184,7 +186,7 @@
 #define MESSAGE_PUMP_UI NULL
 #define MESSAGE_PUMP_IO NULL
 #elif defined(OS_POSIX)  // POSIX but not MACOSX.
-#define MESSAGE_PUMP_UI new base::MessagePumpForUI()
+#define MESSAGE_PUMP_UI new base::MessagePumpGtk()
 #define MESSAGE_PUMP_IO new base::MessagePumpLibevent()
 #else
 #error Not implemented
diff --git a/base/message_loop.h b/base/message_loop.h
index 9a03d6b..8fd9cbc 100644
--- a/base/message_loop.h
+++ b/base/message_loop.h
@@ -27,13 +27,14 @@
 #elif defined(OS_POSIX)
 #include "base/message_pump_libevent.h"
 #if !defined(OS_MACOSX)
-#include "base/message_pump_glib.h"
+#if defined(TOUCH_UI)
+#include "base/message_pump_x.h"
+#else
+#include "base/message_pump_gtk.h"
+#endif
 typedef struct _XDisplay Display;
 #endif
 #endif
-#if defined(TOUCH_UI)
-#include "base/message_pump_glib_x_dispatch.h"
-#endif
 
 namespace base {
 class Histogram;
@@ -80,12 +81,9 @@
 #if defined(OS_WIN)
   typedef base::MessagePumpWin::Dispatcher Dispatcher;
   typedef base::MessagePumpForUI::Observer Observer;
-#elif defined(TOUCH_UI)
-  typedef base::MessagePumpGlibXDispatcher Dispatcher;
-  typedef base::MessagePumpXObserver Observer;
 #elif !defined(OS_MACOSX)
-  typedef base::MessagePumpForUI::Dispatcher Dispatcher;
-  typedef base::MessagePumpForUI::Observer Observer;
+  typedef base::MessagePumpDispatcher Dispatcher;
+  typedef base::MessagePumpObserver Observer;
 #endif
 
   // A MessageLoop has a particular type, which indicates the set of
diff --git a/base/message_pump_glib.cc b/base/message_pump_glib.cc
index 721fedb..20fc8ea 100644
--- a/base/message_pump_glib.cc
+++ b/base/message_pump_glib.cc
@@ -1,4 +1,4 @@
-// Copyright (c) 2010 The Chromium Authors. All rights reserved.
+// Copyright (c) 2011 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.
 
@@ -7,7 +7,6 @@
 #include <fcntl.h>
 #include <math.h>
 
-#include <gtk/gtk.h>
 #include <glib.h>
 
 #include "base/eintr_wrapper.h"
@@ -85,7 +84,7 @@
 // loop, around event handling.
 
 struct WorkSource : public GSource {
-  base::MessagePumpForUI* pump;
+  base::MessagePumpGlib* pump;
 };
 
 gboolean WorkSourcePrepare(GSource* source,
@@ -124,9 +123,9 @@
 
 namespace base {
 
-struct MessagePumpForUI::RunState {
+struct MessagePumpGlib::RunState {
   Delegate* delegate;
-  Dispatcher* dispatcher;
+  MessagePumpDispatcher* dispatcher;
 
   // Used to flag that the current Run() invocation should return ASAP.
   bool should_quit;
@@ -140,7 +139,7 @@
   bool has_work;
 };
 
-MessagePumpForUI::MessagePumpForUI()
+MessagePumpGlib::MessagePumpGlib()
     : state_(NULL),
       context_(g_main_context_default()),
       wakeup_gpollfd_(new GPollFD) {
@@ -160,26 +159,23 @@
   // This is needed to allow Run calls inside Dispatch.
   g_source_set_can_recurse(work_source_, TRUE);
   g_source_attach(work_source_, context_);
-  gdk_event_handler_set(&EventDispatcher, this, NULL);
 }
 
-MessagePumpForUI::~MessagePumpForUI() {
-  gdk_event_handler_set(reinterpret_cast<GdkEventFunc>(gtk_main_do_event),
-                        this, NULL);
+MessagePumpGlib::~MessagePumpGlib() {
   g_source_destroy(work_source_);
   g_source_unref(work_source_);
   close(wakeup_pipe_read_);
   close(wakeup_pipe_write_);
 }
 
-void MessagePumpForUI::RunWithDispatcher(Delegate* delegate,
-                                         Dispatcher* dispatcher) {
+void MessagePumpGlib::RunWithDispatcher(Delegate* delegate,
+                                        MessagePumpDispatcher* dispatcher) {
 #ifndef NDEBUG
-  // Make sure we only run this on one thread.  GTK only has one message pump
+  // Make sure we only run this on one thread. X/GTK only has one message pump
   // so we can only have one UI loop per process.
   static base::PlatformThreadId thread_id = base::PlatformThread::CurrentId();
   DCHECK(thread_id == base::PlatformThread::CurrentId()) <<
-      "Running MessagePumpForUI on two different threads; "
+      "Running MessagePumpGlib on two different threads; "
       "this is unsupported by GLib!";
 #endif
 
@@ -231,13 +227,8 @@
   state_ = previous_state;
 }
 
-bool MessagePumpForUI::RunOnce(GMainContext* context, bool block) {
-  // g_main_context_iteration returns true if events have been dispatched.
-  return g_main_context_iteration(context, block);
-}
-
 // Return the timeout we want passed to poll.
-int MessagePumpForUI::HandlePrepare() {
+int MessagePumpGlib::HandlePrepare() {
   // We know we have work, but we haven't called HandleDispatch yet. Don't let
   // the pump block so that we can do some processing.
   if (state_ &&  // state_ may be null during tests.
@@ -249,7 +240,7 @@
   return GetTimeIntervalMilliseconds(delayed_work_time_);
 }
 
-bool MessagePumpForUI::HandleCheck() {
+bool MessagePumpGlib::HandleCheck() {
   if (!state_)  // state_ may be null during tests.
     return false;
 
@@ -279,11 +270,11 @@
   return false;
 }
 
-void MessagePumpForUI::HandleDispatch() {
+void MessagePumpGlib::HandleDispatch() {
   state_->has_work = false;
   if (state_->delegate->DoWork()) {
     // NOTE: on Windows at this point we would call ScheduleWork (see
-    // MessagePumpForUI::HandleWorkMessage in message_pump_win.cc). But here,
+    // MessagePumpGlib::HandleWorkMessage in message_pump_win.cc). But here,
     // instead of posting a message on the wakeup pipe, we can avoid the
     // syscalls and just signal that we have more work.
     state_->has_work = true;
@@ -295,30 +286,19 @@
   state_->delegate->DoDelayedWork(&delayed_work_time_);
 }
 
-void MessagePumpForUI::AddObserver(Observer* observer) {
+void MessagePumpGlib::AddObserver(MessagePumpObserver* observer) {
   observers_.AddObserver(observer);
 }
 
-void MessagePumpForUI::RemoveObserver(Observer* observer) {
+void MessagePumpGlib::RemoveObserver(MessagePumpObserver* observer) {
   observers_.RemoveObserver(observer);
 }
 
-void MessagePumpForUI::DispatchEvents(GdkEvent* event) {
-  WillProcessEvent(event);
-  if (state_ && state_->dispatcher) { // state_ may be null during tests.
-    if (!state_->dispatcher->Dispatch(event))
-      state_->should_quit = true;
-  } else {
-    gtk_main_do_event(event);
-  }
-  DidProcessEvent(event);
-}
-
-void MessagePumpForUI::Run(Delegate* delegate) {
+void MessagePumpGlib::Run(Delegate* delegate) {
   RunWithDispatcher(delegate, NULL);
 }
 
-void MessagePumpForUI::Quit() {
+void MessagePumpGlib::Quit() {
   if (state_) {
     state_->should_quit = true;
   } else {
@@ -326,7 +306,7 @@
   }
 }
 
-void MessagePumpForUI::ScheduleWork() {
+void MessagePumpGlib::ScheduleWork() {
   // This can be called on any thread, so we don't want to touch any state
   // variables as we would then need locks all over.  This ensures that if
   // we are sleeping in a poll that we will wake up.
@@ -336,29 +316,15 @@
   }
 }
 
-void MessagePumpForUI::ScheduleDelayedWork(const TimeTicks& delayed_work_time) {
+void MessagePumpGlib::ScheduleDelayedWork(const TimeTicks& delayed_work_time) {
   // We need to wake up the loop in case the poll timeout needs to be
   // adjusted.  This will cause us to try to do work, but that's ok.
   delayed_work_time_ = delayed_work_time;
   ScheduleWork();
 }
 
-MessagePumpForUI::Dispatcher* MessagePumpForUI::GetDispatcher() {
+MessagePumpDispatcher* MessagePumpGlib::GetDispatcher() {
   return state_ ? state_->dispatcher : NULL;
 }
 
-void MessagePumpForUI::WillProcessEvent(GdkEvent* event) {
-  FOR_EACH_OBSERVER(Observer, observers_, WillProcessEvent(event));
-}
-
-void MessagePumpForUI::DidProcessEvent(GdkEvent* event) {
-  FOR_EACH_OBSERVER(Observer, observers_, DidProcessEvent(event));
-}
-
-// static
-void MessagePumpForUI::EventDispatcher(GdkEvent* event, gpointer data) {
-  MessagePumpForUI* message_pump = reinterpret_cast<MessagePumpForUI*>(data);
-  message_pump->DispatchEvents(event);
-}
-
 }  // namespace base
diff --git a/base/message_pump_glib.h b/base/message_pump_glib.h
index 32d0d8f..36d75cd 100644
--- a/base/message_pump_glib.h
+++ b/base/message_pump_glib.h
@@ -11,56 +11,40 @@
 #include "base/observer_list.h"
 #include "base/time.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 {
+// MessagePumpObserver is notified prior to an event being dispatched. As
+// Observers are notified of every change, they have to be FAST! The platform
+// specific implementation of the class is in message_pump_gtk/message_pump_x.
+class MessagePumpObserver;
+
+// MessagePumpDispatcher is used during a nested invocation of Run to dispatch
+// events. If Run is invoked with a non-NULL MessagePumpDispatcher, 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 platform specific
+// implementation of the class is in message_pump_gtk/message_pump_x.
+class MessagePumpDispatcher;
+
+// This class implements a base MessagePump needed for TYPE_UI MessageLoops on
+// platforms using GLib.
+class MessagePumpGlib : 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() {}
+  MessagePumpGlib();
+  virtual ~MessagePumpGlib();
 
-    // 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);
+  // Like MessagePump::Run, but events are routed through dispatcher.
+  virtual void RunWithDispatcher(Delegate* delegate,
+                                 MessagePumpDispatcher* dispatcher);
 
   // Run a single iteration of the mainloop. A return value of true indicates
   // that an event was handled. |block| indicates if it should wait if no event
   // is ready for processing.
-  virtual bool RunOnce(GMainContext* context, bool block);
+  virtual bool RunOnce(GMainContext* context, bool block) = 0;
 
   // Internal methods used for processing the pump callbacks.  They are
   // public for simplicity but should not be used directly.  HandlePrepare
@@ -73,15 +57,11 @@
   void HandleDispatch();
 
   // Adds an Observer, which will start receiving notifications immediately.
-  void AddObserver(Observer* observer);
+  void AddObserver(MessagePumpObserver* observer);
 
   // Removes an Observer.  It is safe to call this method while an Observer is
   // receiving a notification callback.
-  void RemoveObserver(Observer* observer);
-
-  // Dispatch an available GdkEvent. Essentially this allows a subclass to do
-  // some task before/after calling the default handler (EventDispatcher).
-  virtual void DispatchEvents(GdkEvent* event);
+  void RemoveObserver(MessagePumpObserver* observer);
 
   // Overridden from MessagePump:
   virtual void Run(Delegate* delegate);
@@ -91,26 +71,15 @@
 
  protected:
   // Returns the dispatcher for the current run state (|state_->dispatcher|).
-  Dispatcher* GetDispatcher();
+  MessagePumpDispatcher* GetDispatcher();
 
-  ObserverList<Observer>& observers() { return observers_; }
+  ObserverList<MessagePumpObserver>& observers() { return observers_; }
 
  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;
 
-  // 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
@@ -135,9 +104,9 @@
   scoped_ptr<GPollFD> wakeup_gpollfd_;
 
   // List of observers.
-  ObserverList<Observer> observers_;
+  ObserverList<MessagePumpObserver> observers_;
 
-  DISALLOW_COPY_AND_ASSIGN(MessagePumpForUI);
+  DISALLOW_COPY_AND_ASSIGN(MessagePumpGlib);
 };
 
 }  // namespace base
diff --git a/base/message_pump_glib_x.h b/base/message_pump_glib_x.h
deleted file mode 100644
index ed29e6a..0000000
--- a/base/message_pump_glib_x.h
+++ /dev/null
@@ -1,97 +0,0 @@
-// Copyright (c) 2011 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_X_H
-#define BASE_MESSAGE_PUMP_GLIB_X_H
-
-#include "base/message_pump.h"
-#include "base/message_pump_glib.h"
-
-#include <bitset>
-
-#include <glib.h>
-#include <gtk/gtk.h>
-#include <X11/X.h>
-
-typedef union _XEvent XEvent;
-
-namespace base {
-
-class MessagePumpGlibX : public MessagePumpForUI {
- public:
-  MessagePumpGlibX();
-  virtual ~MessagePumpGlibX();
-
-  // Indicates whether a GDK event was injected by chrome (when |true|) or if it
-  // was captured and being processed by GDK (when |false|).
-  bool IsDispatchingEvent(void) { return dispatching_event_; }
-
-  // Overridden from MessagePumpForUI:
-  virtual bool RunOnce(GMainContext* context, bool block);
-
- private:
-  // Some XEvent's can't be directly read from X event queue and will go
-  // through GDK's dispatching process and may get discarded. This function
-  // sets up a filter to intercept those XEvent's we are interested in
-  // and dispatches them so that they won't get lost.
-  static GdkFilterReturn GdkEventFilter(GdkXEvent* gxevent,
-                                        GdkEvent* gevent,
-                                        gpointer data);
-
-  static void EventDispatcherX(GdkEvent* event, gpointer data);
-
-  // Decides whether we are interested in processing this XEvent.
-  bool ShouldCaptureXEvent(XEvent* event);
-
-  // Dispatches the XEvent and returns true if we should exit the current loop
-  // of message processing.
-  bool ProcessXEvent(XEvent* event);
-
-  // Sends the event to the observers. If an observer returns true, then it does
-  // not send the event to any other observers and returns true. Returns false
-  // if no observer returns true.
-  bool WillProcessXEvent(XEvent* xevent);
-
-  // Update the lookup table and flag the events that should be captured and
-  // processed so that GDK doesn't get to them.
-  void InitializeEventsToCapture(void);
-
-#if defined(HAVE_XINPUT2)
-  // Initialize X2 input.
-  void InitializeXInput2(void);
-
-  // The opcode used for checking events.
-  int xiopcode_;
-#endif
-
-  // The event source for GDK events.
-  GSource* gdksource_;
-
-  // The default GDK event dispatcher. This is stored so that it can be restored
-  // when necessary during nested event dispatching.
-  gboolean (*gdkdispatcher_)(GSource*, GSourceFunc, void*);
-
-  // Indicates whether a GDK event was injected by chrome (when |true|) or if it
-  // was captured and being processed by GDK (when |false|).
-  bool dispatching_event_;
-
-#if ! GTK_CHECK_VERSION(2,18,0)
-// GDK_EVENT_LAST was introduced in GTK+ 2.18.0. For earlier versions, we pick a
-// large enough value (the value of GDK_EVENT_LAST in 2.18.0) so that it works
-// for all versions.
-#define GDK_EVENT_LAST 37
-#endif
-
-  // We do not want to process all the events ourselves. So we use a lookup
-  // table to quickly check if a particular event should be handled by us or if
-  // it should be passed on to the default GDK handler.
-  std::bitset<LASTEvent> capture_x_events_;
-  std::bitset<GDK_EVENT_LAST> capture_gdk_events_;
-
-  DISALLOW_COPY_AND_ASSIGN(MessagePumpGlibX);
-};
-
-}  // namespace base
-
-#endif  // BASE_MESSAGE_PUMP_GLIB_X_H
diff --git a/base/message_pump_glib_x_dispatch.h b/base/message_pump_glib_x_dispatch.h
deleted file mode 100644
index 9a2358a..0000000
--- a/base/message_pump_glib_x_dispatch.h
+++ /dev/null
@@ -1,46 +0,0 @@
-// Copyright (c) 2011 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_X_DISPATCH_H
-#define BASE_MESSAGE_PUMP_GLIB_X_DISPATCH_H
-
-#include "base/base_api.h"
-#include "base/message_pump.h"
-#include "base/message_pump_glib.h"
-
-typedef union _XEvent XEvent;
-
-namespace base {
-
-// The message pump used for TOUCH_UI on linux is MessagePumpGlibX, which can
-// dispatch both GdkEvents* and XEvents* captured directly from X.
-// MessagePumpForUI::Dispatcher provides the mechanism for dispatching
-// GdkEvents. This class provides additional mechanism for dispatching XEvents.
-class MessagePumpGlibXDispatcher : public MessagePumpForUI::Dispatcher {
- public:
-  enum DispatchStatus {
-    EVENT_IGNORED,    // The event was not processed.
-    EVENT_PROCESSED,  // The event has been processed.
-    EVENT_QUIT        // The event was processed and the message-loop should
-                      // terminate.
-  };
-
-  // Dispatches the event. EVENT_IGNORED is returned if the event was ignored
-  // (i.e. not processed). EVENT_PROCESSED is returned if the event was
-  // processed. The nested loop exits immediately if EVENT_QUIT is returned.
-  virtual DispatchStatus DispatchX(XEvent* xevent) = 0;
-};
-
-class BASE_API MessagePumpXObserver : public MessagePumpForUI::Observer {
- public:
-  // This method is called before processing an XEvent. If the method returns
-  // true, it indicates the event has already been handled, so the event is not
-  // processed any farther. If the method returns false, the event dispatching
-  // proceeds as normal.
-  virtual bool WillProcessXEvent(XEvent* xevent);
-};
-
-}  // namespace base
-
-#endif  // BASE_MESSAGE_PUMP_GLIB_X_DISPATCH_H
diff --git a/base/message_pump_gtk.cc b/base/message_pump_gtk.cc
new file mode 100644
index 0000000..f5ed042
--- /dev/null
+++ b/base/message_pump_gtk.cc
@@ -0,0 +1,52 @@
+// Copyright (c) 2011 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_gtk.h"
+
+#include <gtk/gtk.h>
+
+namespace base {
+
+MessagePumpGtk::MessagePumpGtk() : MessagePumpGlib() {
+  gdk_event_handler_set(&EventDispatcher, this, NULL);
+}
+
+MessagePumpGtk::~MessagePumpGtk() {
+  gdk_event_handler_set(reinterpret_cast<GdkEventFunc>(gtk_main_do_event),
+                        this, NULL);
+}
+
+void MessagePumpGtk::DispatchEvents(GdkEvent* event) {
+  WillProcessEvent(event);
+
+  MessagePumpDispatcher* dispatcher = GetDispatcher();
+  if (!dispatcher)
+    gtk_main_do_event(event);
+  else if (!dispatcher->Dispatch(event))
+    Quit();
+
+  DidProcessEvent(event);
+}
+
+bool MessagePumpGtk::RunOnce(GMainContext* context, bool block) {
+  // g_main_context_iteration returns true if events have been dispatched.
+  return g_main_context_iteration(context, block);
+}
+
+void MessagePumpGtk::WillProcessEvent(GdkEvent* event) {
+  FOR_EACH_OBSERVER(MessagePumpObserver, observers(), WillProcessEvent(event));
+}
+
+void MessagePumpGtk::DidProcessEvent(GdkEvent* event) {
+  FOR_EACH_OBSERVER(MessagePumpObserver, observers(), DidProcessEvent(event));
+}
+
+// static
+void MessagePumpGtk::EventDispatcher(GdkEvent* event, gpointer data) {
+  MessagePumpGtk* message_pump = reinterpret_cast<MessagePumpGtk*>(data);
+  message_pump->DispatchEvents(event);
+}
+
+}  // namespace base
+
diff --git a/base/message_pump_gtk.h b/base/message_pump_gtk.h
new file mode 100644
index 0000000..72eaafa
--- /dev/null
+++ b/base/message_pump_gtk.h
@@ -0,0 +1,74 @@
+// Copyright (c) 2011 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_GTK_H_
+#define BASE_MESSAGE_PUMP_GTK_H_
+#pragma once
+
+#include "base/message_pump_glib.h"
+
+typedef union _GdkEvent GdkEvent;
+
+namespace base {
+
+// The documentation for this class is in message_pump_glib.h
+class MessagePumpObserver {
+ public:
+  // 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;
+
+ protected:
+  virtual ~MessagePumpObserver() {}
+};
+
+// The documentation for this class is in message_pump_glib.h
+//
+// The nested loop is exited by either posting a quit, or returning false
+// from Dispatch.
+class MessagePumpDispatcher {
+ public:
+  // 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;
+
+ protected:
+  virtual ~MessagePumpDispatcher() {}
+};
+
+// This class implements a message-pump for dispatching GTK events.
+class MessagePumpGtk : public MessagePumpGlib {
+ public:
+  MessagePumpGtk();
+  virtual ~MessagePumpGtk();
+
+  // Dispatch an available GdkEvent. Essentially this allows a subclass to do
+  // some task before/after calling the default handler (EventDispatcher).
+  void DispatchEvents(GdkEvent* event);
+
+ private:
+  // Overridden from MessagePumpGlib
+  virtual bool RunOnce(GMainContext* context, bool block) OVERRIDE;
+
+  // 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);
+
+  DISALLOW_COPY_AND_ASSIGN(MessagePumpGtk);
+};
+
+typedef MessagePumpGtk MessagePumpForUI;
+
+}  // namespace base
+
+#endif  // BASE_MESSAGE_PUMP_GTK_H_
diff --git a/base/message_pump_glib_x.cc b/base/message_pump_x.cc
similarity index 72%
rename from base/message_pump_glib_x.cc
rename to base/message_pump_x.cc
index 430d937..a50e182 100644
--- a/base/message_pump_glib_x.cc
+++ b/base/message_pump_x.cc
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#include "base/message_pump_glib_x.h"
+#include "base/message_pump_x.h"
 
 #include <gdk/gdkx.h>
 #if defined(HAVE_XINPUT2)
@@ -11,7 +11,7 @@
 #include <X11/Xlib.h>
 #endif
 
-#include "base/message_pump_glib_x_dispatch.h"
+#include "base/basictypes.h"
 
 namespace {
 
@@ -25,7 +25,7 @@
 
 namespace base {
 
-MessagePumpGlibX::MessagePumpGlibX() : base::MessagePumpForUI(),
+MessagePumpX::MessagePumpX() : MessagePumpGlib(),
 #if defined(HAVE_XINPUT2)
     xiopcode_(-1),
 #endif
@@ -42,15 +42,13 @@
   InitializeEventsToCapture();
 }
 
-MessagePumpGlibX::~MessagePumpGlibX() {
+MessagePumpX::~MessagePumpX() {
   gdk_window_remove_filter(NULL, &GdkEventFilter, this);
-
-  // It is not necessary to reset the GDK event handler using
-  // gdk_event_handler_set since it's done in the destructor for
-  // MessagePumpForUI.
+  gdk_event_handler_set(reinterpret_cast<GdkEventFunc>(gtk_main_do_event),
+                        this, NULL);
 }
 
-bool MessagePumpGlibX::ShouldCaptureXEvent(XEvent* xev) {
+bool MessagePumpX::ShouldCaptureXEvent(XEvent* xev) {
   return capture_x_events_[xev->type]
 #if defined(HAVE_XINPUT2)
         && (xev->type != GenericEvent || xev->xcookie.extension == xiopcode_)
@@ -59,7 +57,7 @@
 }
 
 
-bool MessagePumpGlibX::ProcessXEvent(XEvent* xev) {
+bool MessagePumpX::ProcessXEvent(XEvent* xev) {
   bool should_quit = false;
 
 #if defined(HAVE_XINPUT2)
@@ -70,15 +68,14 @@
   }
 #endif
 
-  if (!WillProcessXEvent(xev)) {
-    MessagePumpGlibXDispatcher::DispatchStatus status =
-      static_cast<MessagePumpGlibXDispatcher*>
-      (GetDispatcher())->DispatchX(xev);
+  if (WillProcessXEvent(xev) == MessagePumpObserver::EVENT_CONTINUE) {
+    MessagePumpDispatcher::DispatchStatus status =
+        GetDispatcher()->Dispatch(xev);
 
-    if (status == MessagePumpGlibXDispatcher::EVENT_QUIT) {
+    if (status == MessagePumpDispatcher::EVENT_QUIT) {
       should_quit = true;
       Quit();
-    } else if (status == MessagePumpGlibXDispatcher::EVENT_IGNORED) {
+    } else if (status == MessagePumpDispatcher::EVENT_IGNORED) {
       VLOG(1) << "Event (" << xev->type << ") not handled.";
     }
   }
@@ -92,10 +89,10 @@
   return should_quit;
 }
 
-bool MessagePumpGlibX::RunOnce(GMainContext* context, bool block) {
+bool MessagePumpX::RunOnce(GMainContext* context, bool block) {
   GdkDisplay* gdisp = gdk_display_get_default();
   if (!gdisp || !GetDispatcher())
-    return MessagePumpForUI::RunOnce(context, block);
+    return g_main_context_iteration(context, block);
 
   Display* display = GDK_DISPLAY_XDISPLAY(gdisp);
 
@@ -137,10 +134,10 @@
   return retvalue;
 }
 
-GdkFilterReturn MessagePumpGlibX::GdkEventFilter(GdkXEvent* gxevent,
-                                                 GdkEvent* gevent,
-                                                 gpointer data) {
-  MessagePumpGlibX* pump = static_cast<MessagePumpGlibX*>(data);
+GdkFilterReturn MessagePumpX::GdkEventFilter(GdkXEvent* gxevent,
+                                             GdkEvent* gevent,
+                                             gpointer data) {
+  MessagePumpX* pump = static_cast<MessagePumpX*>(data);
   XEvent* xev = static_cast<XEvent*>(gxevent);
 
   if (pump->ShouldCaptureXEvent(xev) && pump->GetDispatcher()) {
@@ -151,20 +148,18 @@
   return GDK_FILTER_CONTINUE;
 }
 
-bool MessagePumpGlibX::WillProcessXEvent(XEvent* xevent) {
-  ObserverListBase<Observer>::Iterator it(observers());
-  Observer* obs;
+bool MessagePumpX::WillProcessXEvent(XEvent* xevent) {
+  ObserverListBase<MessagePumpObserver>::Iterator it(observers());
+  MessagePumpObserver* obs;
   while ((obs = it.GetNext()) != NULL) {
-    MessagePumpXObserver* xobs =
-        static_cast<MessagePumpXObserver*>(obs);
-    if (xobs->WillProcessXEvent(xevent))
+    if (obs->WillProcessXEvent(xevent))
       return true;
   }
   return false;
 }
 
-void MessagePumpGlibX::EventDispatcherX(GdkEvent* event, gpointer data) {
-  MessagePumpGlibX* pump_x = reinterpret_cast<MessagePumpGlibX*>(data);
+void MessagePumpX::EventDispatcherX(GdkEvent* event, gpointer data) {
+  MessagePumpX* pump_x = reinterpret_cast<MessagePumpX*>(data);
 
   if (!pump_x->gdksource_) {
     pump_x->gdksource_ = g_main_current_source();
@@ -177,10 +172,10 @@
     }
   }
 
-  pump_x->DispatchEvents(event);
+  gtk_main_do_event(event);
 }
 
-void MessagePumpGlibX::InitializeEventsToCapture(void) {
+void MessagePumpX::InitializeEventsToCapture(void) {
   // TODO(sad): Decide which events we want to capture and update the tables
   // accordingly.
   capture_x_events_[KeyPress] = true;
@@ -204,7 +199,7 @@
 }
 
 #if defined(HAVE_XINPUT2)
-void MessagePumpGlibX::InitializeXInput2(void) {
+void MessagePumpX::InitializeXInput2(void) {
   GdkDisplay* display = gdk_display_get_default();
   if (!display)
     return;
@@ -227,8 +222,11 @@
 }
 #endif  // HAVE_XINPUT2
 
-bool MessagePumpXObserver::WillProcessXEvent(XEvent* xev) {
-  return false;
+MessagePumpObserver::EventStatus
+    MessagePumpObserver::WillProcessXEvent(XEvent* xev) {
+  return EVENT_CONTINUE;
 }
 
+COMPILE_ASSERT(XLASTEvent >= LASTEvent, XLASTEvent_too_small);
+
 }  // namespace base
diff --git a/base/message_pump_x.h b/base/message_pump_x.h
new file mode 100644
index 0000000..f7f271c
--- /dev/null
+++ b/base/message_pump_x.h
@@ -0,0 +1,144 @@
+// Copyright (c) 2011 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_X_H
+#define BASE_MESSAGE_PUMP_X_H
+
+#include "base/message_pump.h"
+#include "base/message_pump_glib.h"
+
+#include <bitset>
+
+#include <glib.h>
+#include <gtk/gtk.h>
+
+typedef union _XEvent XEvent;
+
+namespace base {
+
+// The documentation for this class is in message_pump_glib.h
+class BASE_API MessagePumpObserver {
+ public:
+   enum EventStatus {
+     EVENT_CONTINUE,    // The event should be dispatched as normal.
+     EVENT_HANDLED      // The event should not be processed any farther.
+   };
+
+  // This method is called before processing an XEvent. If the method returns
+  // EVENT_HANDLED, it indicates the event has already been handled, so the
+  // event is not processed any farther. If the method returns EVENT_CONTINUE,
+  // the event dispatching proceeds as normal.
+  virtual EventStatus WillProcessXEvent(XEvent* xevent);
+
+ protected:
+  virtual ~MessagePumpObserver() {}
+};
+
+// The documentation for this class is in message_pump_glib.h
+//
+// The nested loop is exited by either posting a quit, or returning EVENT_QUIT
+// from Dispatch.
+class MessagePumpDispatcher {
+ public:
+  enum DispatchStatus {
+    EVENT_IGNORED,    // The event was not processed.
+    EVENT_PROCESSED,  // The event has been processed.
+    EVENT_QUIT        // The event was processed and the message-loop should
+                      // terminate.
+  };
+
+  // Dispatches the event. EVENT_IGNORED is returned if the event was ignored
+  // (i.e. not processed). EVENT_PROCESSED is returned if the event was
+  // processed. The nested loop exits immediately if EVENT_QUIT is returned.
+  virtual DispatchStatus Dispatch(XEvent* xevent) = 0;
+
+ protected:
+  virtual ~MessagePumpDispatcher() {}
+};
+
+// This class implements a message-pump for dispatching X events.
+class MessagePumpX : public MessagePumpGlib {
+ public:
+  MessagePumpX();
+  virtual ~MessagePumpX();
+
+  // Indicates whether a GDK event was injected by chrome (when |true|) or if it
+  // was captured and being processed by GDK (when |false|).
+  bool IsDispatchingEvent(void) { return dispatching_event_; }
+
+  // Overridden from MessagePumpGlib:
+  virtual bool RunOnce(GMainContext* context, bool block) OVERRIDE;
+
+ private:
+  // Some XEvent's can't be directly read from X event queue and will go
+  // through GDK's dispatching process and may get discarded. This function
+  // sets up a filter to intercept those XEvent's we are interested in
+  // and dispatches them so that they won't get lost.
+  static GdkFilterReturn GdkEventFilter(GdkXEvent* gxevent,
+                                        GdkEvent* gevent,
+                                        gpointer data);
+
+  static void EventDispatcherX(GdkEvent* event, gpointer data);
+
+  // Decides whether we are interested in processing this XEvent.
+  bool ShouldCaptureXEvent(XEvent* event);
+
+  // Dispatches the XEvent and returns true if we should exit the current loop
+  // of message processing.
+  bool ProcessXEvent(XEvent* event);
+
+  // Sends the event to the observers. If an observer returns true, then it does
+  // not send the event to any other observers and returns true. Returns false
+  // if no observer returns true.
+  bool WillProcessXEvent(XEvent* xevent);
+
+  // Update the lookup table and flag the events that should be captured and
+  // processed so that GDK doesn't get to them.
+  void InitializeEventsToCapture(void);
+
+#if defined(HAVE_XINPUT2)
+  // Initialize X2 input.
+  void InitializeXInput2(void);
+
+  // The opcode used for checking events.
+  int xiopcode_;
+#endif
+
+  // The event source for GDK events.
+  GSource* gdksource_;
+
+  // The default GDK event dispatcher. This is stored so that it can be restored
+  // when necessary during nested event dispatching.
+  gboolean (*gdkdispatcher_)(GSource*, GSourceFunc, void*);
+
+  // Indicates whether a GDK event was injected by chrome (when |true|) or if it
+  // was captured and being processed by GDK (when |false|).
+  bool dispatching_event_;
+
+#if ! GTK_CHECK_VERSION(2,18,0)
+// GDK_EVENT_LAST was introduced in GTK+ 2.18.0. For earlier versions, we pick a
+// large enough value (the value of GDK_EVENT_LAST in 2.18.0) so that it works
+// for all versions.
+#define GDK_EVENT_LAST 37
+#endif
+
+// Ideally we would #include X.h for LASTEvent, but it brings in a lot of stupid
+// stuff (like Time, CurrentTime etc.) that messes up a lot of things. So define
+// XLASTEvent here to a large enough value so that it works.
+#define XLASTEvent 40
+
+  // We do not want to process all the events ourselves. So we use a lookup
+  // table to quickly check if a particular event should be handled by us or if
+  // it should be passed on to the default GDK handler.
+  std::bitset<XLASTEvent> capture_x_events_;
+  std::bitset<GDK_EVENT_LAST> capture_gdk_events_;
+
+  DISALLOW_COPY_AND_ASSIGN(MessagePumpX);
+};
+
+typedef MessagePumpX MessagePumpForUI;
+
+}  // namespace base
+
+#endif  // BASE_MESSAGE_PUMP_X_H