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