tor-browser

The Tor Browser
git clone https://git.dasho.dev/tor-browser.git
Log | Files | Refs | README | LICENSE

message_pump_glib.h (3165B)

      1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
      2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
      3 // Copyright (c) 2008 The Chromium Authors. All rights reserved.
      4 // Use of this source code is governed by a BSD-style license that can be
      5 // found in the LICENSE file.
      6 
      7 #ifndef BASE_MESSAGE_PUMP_GLIB_H_
      8 #define BASE_MESSAGE_PUMP_GLIB_H_
      9 
     10 #include "base/message_pump.h"
     11 #include "base/observer_list.h"
     12 #include "base/time.h"
     13 #include "mozilla/UniquePtr.h"
     14 #include "mozilla/Atomics.h"
     15 
     16 typedef struct _GMainContext GMainContext;
     17 typedef struct _GPollFD GPollFD;
     18 typedef struct _GSource GSource;
     19 
     20 namespace base {
     21 
     22 // This class implements a MessagePump needed for TYPE_UI MessageLoops on
     23 // XP_LINUX platforms using GLib.
     24 class MessagePumpForUI : public MessagePump {
     25 public:
     26  MessagePumpForUI();
     27  virtual ~MessagePumpForUI();
     28 
     29  void Run(Delegate* delegate) override;
     30  void Quit() override;
     31  void ScheduleWork() override;
     32  void ScheduleDelayedWork(const TimeTicks& delayed_work_time) override;
     33 
     34  // Internal methods used for processing the pump callbacks.  They are
     35  // public for simplicity but should not be used directly.  HandlePrepare
     36  // is called during the prepare step of glib, and returns a timeout that
     37  // will be passed to the poll. HandleCheck is called after the poll
     38  // has completed, and returns whether or not HandleDispatch should be called.
     39  // HandleDispatch is called if HandleCheck returned true.
     40  int HandlePrepare();
     41  bool HandleCheck();
     42  void HandleDispatch();
     43 
     44 private:
     45  // We may make recursive calls to Run, so we save state that needs to be
     46  // separate between them in this structure type.
     47  struct RunState {
     48    Delegate* delegate;
     49 
     50    // Used to flag that the current Run() invocation should return ASAP.
     51    bool should_quit;
     52 
     53    // Used to count how many Run() invocations are on the stack.
     54    int run_depth;
     55 
     56    // This keeps the state of whether the pump got signaled that there was new
     57    // work to be done. Since we eat the message on the wake up pipe as soon as
     58    // we get it, we keep that state here to stay consistent.
     59    bool has_work;
     60  };
     61 
     62  RunState* state_;
     63 
     64  // This is a GLib structure that we can add event sources to.  We use the
     65  // default GLib context, which is the one to which all GTK events are
     66  // dispatched.
     67  GMainContext* context_;
     68 
     69  // This is the time when we need to do delayed work.
     70  TimeTicks delayed_work_time_;
     71 
     72  // The work source.  It is shared by all calls to Run and destroyed when
     73  // the message pump is destroyed.
     74  GSource* work_source_;
     75 
     76  // We use a wakeup pipe to make sure we'll get out of the glib polling phase
     77  // when another thread has scheduled us to do some work.  There is a glib
     78  // mechanism g_main_context_wakeup, but this won't guarantee that our event's
     79  // Dispatch() will be called.
     80  int wakeup_pipe_read_;
     81  int wakeup_pipe_write_;
     82  // Use an autoptr to avoid needing the definition of GPollFD in the header.
     83  mozilla::UniquePtr<GPollFD> wakeup_gpollfd_;
     84 
     85  mozilla::Atomic<bool> pipe_full_;
     86 
     87  DISALLOW_COPY_AND_ASSIGN(MessagePumpForUI);
     88 };
     89 
     90 }  // namespace base
     91 
     92 #endif  // BASE_MESSAGE_PUMP_GLIB_H_