base/message_loop/message_pump_aurax11.h

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef BASE_MESSAGE_LOOP_MESSAGE_PUMP_AURAX11_H
   6 #define BASE_MESSAGE_LOOP_MESSAGE_PUMP_AURAX11_H
   7
   8 #include <bitset>
   9 #include <map>
  10
  11 #include "base/memory/scoped_ptr.h"
  12 #include "base/message_loop/message_pump.h"
  13 #include "base/message_loop/message_pump_dispatcher.h"
  14 #include "base/message_loop/message_pump_glib.h"
  15 #include "base/message_loop/message_pump_observer.h"
  16 #include "base/observer_list.h"
  17
  18 // It would be nice to include the X11 headers here so that we use Window
  19 // instead of its typedef of unsigned long, but we can't because everything in
  20 // chrome includes us through base/message_loop/message_loop.h, and X11's crappy
  21 // #define heavy headers muck up half of chrome.
  22
  23 typedef struct _GPollFD GPollFD;
  24 typedef struct _GSource GSource;
  25 typedef struct _XDisplay Display;
  26
  27 namespace base {
  28
  29 // This class implements a message-pump for dispatching X events.
  30 //
  31 // If there's a current dispatcher given through RunWithDispatcher(), that
  32 // dispatcher receives events. Otherwise, we route to messages to dispatchers
  33 // who have subscribed to messages from a specific X11 window.
  34 class BASE_EXPORT MessagePumpAuraX11 : public MessagePumpGlib,
  35                                        public MessagePumpDispatcher {
  36  public:
  37   MessagePumpAuraX11();
  38   virtual ~MessagePumpAuraX11();
  39
  40   // Returns default X Display.
  41   static Display* GetDefaultXDisplay();
  42
  43   // Returns true if the system supports XINPUT2.
  44   static bool HasXInput2();
  45
  46   // Returns the UI message pump.
  47   static MessagePumpAuraX11* Current();
  48
  49   // Adds/Removes |dispatcher| for the |xid|. This will route all messages from
  50   // the window |xid| to |dispatcher.
  51   void AddDispatcherForWindow(MessagePumpDispatcher* dispatcher,
  52                               unsigned long xid);
  53   void RemoveDispatcherForWindow(unsigned long xid);
  54
  55   // Adds/Removes |dispatcher| to receive all events sent to the X root
  56   // window. A root window can have multiple dispatchers, and events on root
  57   // windows will be dispatched to all.
  58   void AddDispatcherForRootWindow(MessagePumpDispatcher* dispatcher);
  59   void RemoveDispatcherForRootWindow(MessagePumpDispatcher* dispatcher);
  60
  61   // Internal function. Called by the glib source dispatch function. Processes
  62   // all available X events.
  63   bool DispatchXEvents();
  64
  65   // Blocks on the X11 event queue until we receive notification from the
  66   // xserver that |w| has been mapped; StructureNotifyMask events on |w| are
  67   // pulled out from the queue and dispatched out of order.
  68   //
  69   // For those that know X11, this is really a wrapper around XWindowEvent
  70   // which still makes sure the preempted event is dispatched instead of
  71   // dropped on the floor. This method exists because mapping a window is
  72   // asynchronous (and we receive an XEvent when mapped), while there are also
  73   // functions which require a mapped window.
  74   void BlockUntilWindowMapped(unsigned long xid);
  75
  76  private:
  77   typedef std::map<unsigned long, MessagePumpDispatcher*> DispatchersMap;
  78
  79   // Initializes the glib event source for X.
  80   void InitXSource();
  81
  82   // Dispatches the XEvent and returns true if we should exit the current loop
  83   // of message processing.
  84   bool ProcessXEvent(MessagePumpDispatcher* dispatcher, XEvent* event);
  85
  86   // Sends the event to the observers. If an observer returns true, then it does
  87   // not send the event to any other observers and returns true. Returns false
  88   // if no observer returns true.
  89   bool WillProcessXEvent(XEvent* xevent);
  90   void DidProcessXEvent(XEvent* xevent);
  91
  92   // Returns the Dispatcher based on the event's target window.
  93   MessagePumpDispatcher* GetDispatcherForXEvent(const NativeEvent& xev) const;
  94
  95   // Overridden from MessagePumpDispatcher:
  96   virtual bool Dispatch(const NativeEvent& event) OVERRIDE;
  97
  98   // The event source for X events.
  99   GSource* x_source_;
 100
 101   // The poll attached to |x_source_|.
 102   scoped_ptr<GPollFD> x_poll_;
 103
 104   DispatchersMap dispatchers_;
 105
 106   // Dispatch calls can cause addition of new dispatchers as we iterate
 107   // through them. Use ObserverList to ensure the iterator remains valid across
 108   // additions.
 109   ObserverList<MessagePumpDispatcher> root_window_dispatchers_;
 110
 111   unsigned long x_root_window_;
 112
 113   DISALLOW_COPY_AND_ASSIGN(MessagePumpAuraX11);
 114 };
 115
 116 typedef MessagePumpAuraX11 MessagePumpForUI;
 117
 118 }  // namespace base
 119
 120 #endif  // BASE_MESSAGE_LOOP_MESSAGE_PUMP_AURAX11_H