base/run_loop.cc

   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 #include "base/run_loop.h"
   6
   7 #include "base/bind.h"
   8
   9 #if defined(OS_WIN)
  10 #include "base/message_loop/message_pump_dispatcher.h"
  11 #endif
  12
  13 namespace base {
  14
  15 RunLoop::RunLoop()
  16     : loop_(MessageLoop::current()),
  17       previous_run_loop_(NULL),
  18       run_depth_(0),
  19       run_called_(false),
  20       quit_called_(false),
  21       running_(false),
  22       quit_when_idle_received_(false),
  23       weak_factory_(this) {
  24 #if defined(OS_WIN)
  25    dispatcher_ = NULL;
  26 #endif
  27 }
  28
  29 #if defined(OS_WIN)
  30 RunLoop::RunLoop(MessagePumpDispatcher* dispatcher)
  31     : loop_(MessageLoop::current()),
  32       previous_run_loop_(NULL),
  33       dispatcher_(dispatcher),
  34       run_depth_(0),
  35       run_called_(false),
  36       quit_called_(false),
  37       running_(false),
  38       quit_when_idle_received_(false),
  39       weak_factory_(this) {
  40 }
  41 #endif
  42
  43 RunLoop::~RunLoop() {
  44 }
  45
  46 void RunLoop::Run() {
  47   if (!BeforeRun())
  48     return;
  49   loop_->RunHandler();
  50   AfterRun();
  51 }
  52
  53 void RunLoop::RunUntilIdle() {
  54   quit_when_idle_received_ = true;
  55   Run();
  56 }
  57
  58 void RunLoop::Quit() {
  59   quit_called_ = true;
  60   if (running_ && loop_->run_loop_ == this) {
  61     // This is the inner-most RunLoop, so quit now.
  62     loop_->QuitNow();
  63   }
  64 }
  65
  66 base::Closure RunLoop::QuitClosure() {
  67   return base::Bind(&RunLoop::Quit, weak_factory_.GetWeakPtr());
  68 }
  69
  70 bool RunLoop::BeforeRun() {
  71   DCHECK(!run_called_);
  72   run_called_ = true;
  73
  74   // Allow Quit to be called before Run.
  75   if (quit_called_)
  76     return false;
  77
  78   // Push RunLoop stack:
  79   previous_run_loop_ = loop_->run_loop_;
  80   run_depth_ = previous_run_loop_? previous_run_loop_->run_depth_ + 1 : 1;
  81   loop_->run_loop_ = this;
  82
  83   running_ = true;
  84   return true;
  85 }
  86
  87 void RunLoop::AfterRun() {
  88   running_ = false;
  89
  90   // Pop RunLoop stack:
  91   loop_->run_loop_ = previous_run_loop_;
  92
  93   // Execute deferred QuitNow, if any:
  94   if (previous_run_loop_ && previous_run_loop_->quit_called_)
  95     loop_->QuitNow();
  96 }
  97
  98 }  // namespace base