base/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_PUMP_AURAX11_H
   6 #define BASE_MESSAGE_PUMP_AURAX11_H
   7
   8 #include <bitset>
   9 #include <map>
  10
  11 #include "base/memory/scoped_ptr.h"
  12 #include "base/message_pump.h"
  13 #include "base/message_pump_glib.h"
  14 #include "base/message_pump_dispatcher.h"
  15 #include "base/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.h, and X11's crappy #define
  21 // 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
  39   // Returns default X Display.
  40   static Display* GetDefaultXDisplay();
  41
  42   // Returns true if the system supports XINPUT2.
  43   static bool HasXInput2();
  44
  45   // Returns the UI message pump.
  46   static MessagePumpAuraX11* Current();
  47
  48   // Adds/Removes |dispatcher| for the |xid|. This will route all messages from
  49   // the window |xid| to |dispatcher.
  50   void AddDispatcherForWindow(MessagePumpDispatcher* dispatcher,
  51                               unsigned long xid);
  52   void RemoveDispatcherForWindow(unsigned long xid);
  53
  54   // Adds/Removes |dispatcher| to receive all events sent to the X root
  55   // window. A root window can have multiple dispatchers, and events on root
  56   // windows will be dispatched to all.
  57   void AddDispatcherForRootWindow(MessagePumpDispatcher* dispatcher);
  58   void RemoveDispatcherForRootWindow(MessagePumpDispatcher* dispatcher);
  59
  60   // Internal function. Called by the glib source dispatch function. Processes
  61   // all available X events.
  62   bool DispatchXEvents();
  63
  64   // Blocks on the X11 event queue until we receive notification from the
  65   // xserver that |w| has been mapped; StructureNotifyMask events on |w| are
  66   // pulled out from the queue and dispatched out of order.
  67   //
  68   // For those that know X11, this is really a wrapper around XWindowEvent
  69   // which still makes sure the preempted event is dispatched instead of
  70   // dropped on the floor. This method exists because mapping a window is
  71   // asynchronous (and we receive an XEvent when mapped), while there are also
  72   // functions which require a mapped window.
  73   void BlockUntilWindowMapped(unsigned long xid);
  74
  75  protected:
  76   virtual ~MessagePumpAuraX11();
  77
  78  private:
  79   typedef std::map<unsigned long, MessagePumpDispatcher*> DispatchersMap;
  80
  81   // Initializes the glib event source for X.
  82   void InitXSource();
  83
  84   // Dispatches the XEvent and returns true if we should exit the current loop
  85   // of message processing.
  86   bool ProcessXEvent(MessagePumpDispatcher* dispatcher, XEvent* event);
  87
  88   // Sends the event to the observers. If an observer returns true, then it does
  89   // not send the event to any other observers and returns true. Returns false
  90   // if no observer returns true.
  91   bool WillProcessXEvent(XEvent* xevent);
  92   void DidProcessXEvent(XEvent* xevent);
  93
  94   // Returns the Dispatcher based on the event's target window.
  95   MessagePumpDispatcher* GetDispatcherForXEvent(
  96       const base::NativeEvent& xev) const;
  97
  98   // Overridden from MessagePumpDispatcher:
  99   virtual bool Dispatch(const base::NativeEvent& event) OVERRIDE;
 100
 101   // The event source for X events.
 102   GSource* x_source_;
 103
 104   // The poll attached to |x_source_|.
 105   scoped_ptr<GPollFD> x_poll_;
 106
 107   DispatchersMap dispatchers_;
 108
 109   // Dispatch calls can cause addition of new dispatchers as we iterate
 110   // through them. Use ObserverList to ensure the iterator remains valid across
 111   // additions.
 112   ObserverList<MessagePumpDispatcher> root_window_dispatchers_;
 113
 114   unsigned long x_root_window_;
 115
 116   DISALLOW_COPY_AND_ASSIGN(MessagePumpAuraX11);
 117 };
 118
 119 typedef MessagePumpAuraX11 MessagePumpForUI;
 120
 121 }  // namespace base
 122
 123 #endif  // BASE_MESSAGE_PUMP_AURAX11_H