content/child/child_thread_impl.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 "content/child/child_thread_impl.h"
   6
   7 #include <signal.h>
   8
   9 #include <string>
  10
  11 #include "base/allocator/allocator_extension.h"
  12 #include "base/base_switches.h"
  13 #include "base/basictypes.h"
  14 #include "base/command_line.h"
  15 #include "base/debug/leak_annotations.h"
  16 #include "base/debug/profiler.h"
  17 #include "base/lazy_instance.h"
  18 #include "base/location.h"
  19 #include "base/logging.h"
  20 #include "base/message_loop/timer_slack.h"
  21 #include "base/metrics/field_trial.h"
  22 #include "base/process/process.h"
  23 #include "base/process/process_handle.h"
  24 #include "base/single_thread_task_runner.h"
  25 #include "base/strings/string_number_conversions.h"
  26 #include "base/strings/string_util.h"
  27 #include "base/synchronization/condition_variable.h"
  28 #include "base/synchronization/lock.h"
  29 #include "base/thread_task_runner_handle.h"
  30 #include "base/threading/thread_local.h"
  31 #include "base/tracked_objects.h"
  32 #include "components/tracing/child_trace_message_filter.h"
  33 #include "content/child/child_discardable_shared_memory_manager.h"
  34 #include "content/child/child_gpu_memory_buffer_manager.h"
  35 #include "content/child/child_histogram_message_filter.h"
  36 #include "content/child/child_process.h"
  37 #include "content/child/child_resource_message_filter.h"
  38 #include "content/child/child_shared_bitmap_manager.h"
  39 #include "content/child/fileapi/file_system_dispatcher.h"
  40 #include "content/child/fileapi/webfilesystem_impl.h"
  41 #include "content/child/geofencing/geofencing_message_filter.h"
  42 #include "content/child/mojo/mojo_application.h"
  43 #include "content/child/notifications/notification_dispatcher.h"
  44 #include "content/child/power_monitor_broadcast_source.h"
  45 #include "content/child/push_messaging/push_dispatcher.h"
  46 #include "content/child/quota_dispatcher.h"
  47 #include "content/child/quota_message_filter.h"
  48 #include "content/child/resource_dispatcher.h"
  49 #include "content/child/service_worker/service_worker_message_filter.h"
  50 #include "content/child/thread_safe_sender.h"
  51 #include "content/child/websocket_dispatcher.h"
  52 #include "content/common/child_process_messages.h"
  53 #include "content/common/in_process_child_thread_params.h"
  54 #include "content/common/resource_messages.h"
  55 #include "content/public/common/content_switches.h"
  56 #include "ipc/attachment_broker_unprivileged.h"
  57 #include "ipc/ipc_channel.h"
  58 #include "ipc/ipc_logging.h"
  59 #include "ipc/ipc_switches.h"
  60 #include "ipc/ipc_sync_channel.h"
  61 #include "ipc/ipc_sync_message_filter.h"
  62 #include "ipc/mojo/ipc_channel_mojo.h"
  63
  64 #if defined(TCMALLOC_TRACE_MEMORY_SUPPORTED)
  65 #include "third_party/tcmalloc/chromium/src/gperftools/heap-profiler.h"
  66 #endif
  67
  68 #if defined(OS_MACOSX)
  69 #include "content/child/child_io_surface_manager_mac.h"
  70 #endif
  71
  72 #if defined(USE_OZONE)
  73 #include "ui/ozone/public/client_native_pixmap_factory.h"
  74 #endif
  75
  76 #if defined(OS_WIN)
  77 #include "ipc/attachment_broker_unprivileged_win.h"
  78 #endif
  79
  80 using tracked_objects::ThreadData;
  81
  82 namespace content {
  83 namespace {
  84
  85 // How long to wait for a connection to the browser process before giving up.
  86 const int kConnectionTimeoutS = 15;
  87
  88 base::LazyInstance<base::ThreadLocalPointer<ChildThreadImpl> > g_lazy_tls =
  89     LAZY_INSTANCE_INITIALIZER;
  90
  91 // This isn't needed on Windows because there the sandbox's job object
  92 // terminates child processes automatically. For unsandboxed processes (i.e.
  93 // plugins), PluginThread has EnsureTerminateMessageFilter.
  94 #if defined(OS_POSIX)
  95
  96 #if defined(ADDRESS_SANITIZER) || defined(LEAK_SANITIZER) || \
  97     defined(MEMORY_SANITIZER) || defined(THREAD_SANITIZER) || \
  98     defined(UNDEFINED_SANITIZER)
  99 // A thread delegate that waits for |duration| and then exits the process with
 100 // _exit(0).
 101 class WaitAndExitDelegate : public base::PlatformThread::Delegate {
 102  public:
 103   explicit WaitAndExitDelegate(base::TimeDelta duration)
 104       : duration_(duration) {}
 105
 106   void ThreadMain() override {
 107     base::PlatformThread::Sleep(duration_);
 108     _exit(0);
 109   }
 110
 111  private:
 112   const base::TimeDelta duration_;
 113   DISALLOW_COPY_AND_ASSIGN(WaitAndExitDelegate);
 114 };
 115
 116 bool CreateWaitAndExitThread(base::TimeDelta duration) {
 117   scoped_ptr<WaitAndExitDelegate> delegate(new WaitAndExitDelegate(duration));
 118
 119   const bool thread_created =
 120       base::PlatformThread::CreateNonJoinable(0, delegate.get());
 121   if (!thread_created)
 122     return false;
 123
 124   // A non joinable thread has been created. The thread will either terminate
 125   // the process or will be terminated by the process. Therefore, keep the
 126   // delegate object alive for the lifetime of the process.
 127   WaitAndExitDelegate* leaking_delegate = delegate.release();
 128   ANNOTATE_LEAKING_OBJECT_PTR(leaking_delegate);
 129   ignore_result(leaking_delegate);
 130   return true;
 131 }
 132 #endif
 133
 134 class SuicideOnChannelErrorFilter : public IPC::MessageFilter {
 135  public:
 136   // IPC::MessageFilter
 137   void OnChannelError() override {
 138     // For renderer/worker processes:
 139     // On POSIX, at least, one can install an unload handler which loops
 140     // forever and leave behind a renderer process which eats 100% CPU forever.
 141     //
 142     // This is because the terminate signals (FrameMsg_BeforeUnload and the
 143     // error from the IPC sender) are routed to the main message loop but never
 144     // processed (because that message loop is stuck in V8).
 145     //
 146     // One could make the browser SIGKILL the renderers, but that leaves open a
 147     // large window where a browser failure (or a user, manually terminating
 148     // the browser because "it's stuck") will leave behind a process eating all
 149     // the CPU.
 150     //
 151     // So, we install a filter on the sender so that we can process this event
 152     // here and kill the process.
 153     base::debug::StopProfiling();
 154 #if defined(ADDRESS_SANITIZER) || defined(LEAK_SANITIZER) || \
 155     defined(MEMORY_SANITIZER) || defined(THREAD_SANITIZER) || \
 156     defined(UNDEFINED_SANITIZER)
 157     // Some sanitizer tools rely on exit handlers (e.g. to run leak detection,
 158     // or dump code coverage data to disk). Instead of exiting the process
 159     // immediately, we give it 60 seconds to run exit handlers.
 160     CHECK(CreateWaitAndExitThread(base::TimeDelta::FromSeconds(60)));
 161 #if defined(LEAK_SANITIZER)
 162     // Invoke LeakSanitizer early to avoid detecting shutdown-only leaks. If
 163     // leaks are found, the process will exit here.
 164     __lsan_do_leak_check();
 165 #endif
 166 #else
 167     _exit(0);
 168 #endif
 169   }
 170
 171  protected:
 172   ~SuicideOnChannelErrorFilter() override {}
 173 };
 174
 175 #endif  // OS(POSIX)
 176
 177 #if defined(OS_MACOSX)
 178 class IOSurfaceManagerFilter : public IPC::MessageFilter {
 179  public:
 180   // Overridden from IPC::MessageFilter:
 181   bool OnMessageReceived(const IPC::Message& message) override {
 182     bool handled = true;
 183     IPC_BEGIN_MESSAGE_MAP(IOSurfaceManagerFilter, message)
 184       IPC_MESSAGE_HANDLER(ChildProcessMsg_SetIOSurfaceManagerToken,
 185                           OnSetIOSurfaceManagerToken)
 186       IPC_MESSAGE_UNHANDLED(handled = false)
 187     IPC_END_MESSAGE_MAP()
 188     return handled;
 189   }
 190
 191  protected:
 192   ~IOSurfaceManagerFilter() override {}
 193
 194   void OnSetIOSurfaceManagerToken(const IOSurfaceManagerToken& token) {
 195     ChildIOSurfaceManager::GetInstance()->set_token(token);
 196   }
 197 };
 198 #endif
 199
 200 #if defined(USE_OZONE)
 201 class ClientNativePixmapFactoryFilter : public IPC::MessageFilter {
 202  public:
 203   // Overridden from IPC::MessageFilter:
 204   bool OnMessageReceived(const IPC::Message& message) override {
 205     bool handled = true;
 206     IPC_BEGIN_MESSAGE_MAP(ClientNativePixmapFactoryFilter, message)
 207       IPC_MESSAGE_HANDLER(ChildProcessMsg_InitializeClientNativePixmapFactory,
 208                           OnInitializeClientNativePixmapFactory)
 209       IPC_MESSAGE_UNHANDLED(handled = false)
 210     IPC_END_MESSAGE_MAP()
 211     return handled;
 212   }
 213
 214  protected:
 215   ~ClientNativePixmapFactoryFilter() override {}
 216
 217   void OnInitializeClientNativePixmapFactory(
 218       const base::FileDescriptor& device_fd) {
 219     ui::ClientNativePixmapFactory::GetInstance()->Initialize(
 220         base::ScopedFD(device_fd.fd));
 221   }
 222 };
 223 #endif
 224
 225 #if defined(OS_ANDROID)
 226 // A class that allows for triggering a clean shutdown from another
 227 // thread through draining the main thread's msg loop.
 228 class QuitClosure {
 229  public:
 230   QuitClosure();
 231   ~QuitClosure();
 232
 233   void BindToMainThread();
 234   void PostQuitFromNonMainThread();
 235
 236  private:
 237   static void PostClosure(
 238       const scoped_refptr<base::SingleThreadTaskRunner>& task_runner,
 239       base::Closure closure);
 240
 241   base::Lock lock_;
 242   base::ConditionVariable cond_var_;
 243   base::Closure closure_;
 244 };
 245
 246 QuitClosure::QuitClosure() : cond_var_(&lock_) {
 247 }
 248
 249 QuitClosure::~QuitClosure() {
 250 }
 251
 252 void QuitClosure::PostClosure(
 253     const scoped_refptr<base::SingleThreadTaskRunner>& task_runner,
 254     base::Closure closure) {
 255   task_runner->PostTask(FROM_HERE, closure);
 256 }
 257
 258 void QuitClosure::BindToMainThread() {
 259   base::AutoLock lock(lock_);
 260   scoped_refptr<base::SingleThreadTaskRunner> task_runner(
 261       base::ThreadTaskRunnerHandle::Get());
 262   base::Closure quit_closure =
 263       base::MessageLoop::current()->QuitWhenIdleClosure();
 264   closure_ = base::Bind(&QuitClosure::PostClosure, task_runner, quit_closure);
 265   cond_var_.Signal();
 266 }
 267
 268 void QuitClosure::PostQuitFromNonMainThread() {
 269   base::AutoLock lock(lock_);
 270   while (closure_.is_null())
 271     cond_var_.Wait();
 272
 273   closure_.Run();
 274 }
 275
 276 base::LazyInstance<QuitClosure> g_quit_closure = LAZY_INSTANCE_INITIALIZER;
 277 #endif
 278
 279 }  // namespace
 280
 281 ChildThread* ChildThread::Get() {
 282   return ChildThreadImpl::current();
 283 }
 284
 285 ChildThreadImpl::Options::Options()
 286     : channel_name(base::CommandLine::ForCurrentProcess()->GetSwitchValueASCII(
 287           switches::kProcessChannelID)),
 288       use_mojo_channel(false) {
 289 }
 290
 291 ChildThreadImpl::Options::~Options() {
 292 }
 293
 294 ChildThreadImpl::Options::Builder::Builder() {
 295 }
 296
 297 ChildThreadImpl::Options::Builder&
 298 ChildThreadImpl::Options::Builder::InBrowserProcess(
 299     const InProcessChildThreadParams& params) {
 300   options_.browser_process_io_runner = params.io_runner();
 301   options_.channel_name = params.channel_name();
 302   return *this;
 303 }
 304
 305 ChildThreadImpl::Options::Builder&
 306 ChildThreadImpl::Options::Builder::UseMojoChannel(bool use_mojo_channel) {
 307   options_.use_mojo_channel = use_mojo_channel;
 308   return *this;
 309 }
 310
 311 ChildThreadImpl::Options::Builder&
 312 ChildThreadImpl::Options::Builder::WithChannelName(
 313     const std::string& channel_name) {
 314   options_.channel_name = channel_name;
 315   return *this;
 316 }
 317
 318 ChildThreadImpl::Options::Builder&
 319 ChildThreadImpl::Options::Builder::AddStartupFilter(
 320     IPC::MessageFilter* filter) {
 321   options_.startup_filters.push_back(filter);
 322   return *this;
 323 }
 324
 325 ChildThreadImpl::Options ChildThreadImpl::Options::Builder::Build() {
 326   return options_;
 327 }
 328
 329 ChildThreadImpl::ChildThreadMessageRouter::ChildThreadMessageRouter(
 330     IPC::Sender* sender)
 331     : sender_(sender) {}
 332
 333 bool ChildThreadImpl::ChildThreadMessageRouter::Send(IPC::Message* msg) {
 334   return sender_->Send(msg);
 335 }
 336
 337 ChildThreadImpl::ChildThreadImpl()
 338     : router_(this),
 339       channel_connected_factory_(this) {
 340   Init(Options::Builder().Build());
 341 }
 342
 343 ChildThreadImpl::ChildThreadImpl(const Options& options)
 344     : router_(this),
 345       browser_process_io_runner_(options.browser_process_io_runner),
 346       channel_connected_factory_(this) {
 347   Init(options);
 348 }
 349
 350 scoped_refptr<base::SequencedTaskRunner> ChildThreadImpl::GetIOTaskRunner() {
 351   if (IsInBrowserProcess())
 352     return browser_process_io_runner_;
 353   return ChildProcess::current()->io_task_runner();
 354 }
 355
 356 void ChildThreadImpl::ConnectChannel(bool use_mojo_channel) {
 357   bool create_pipe_now = true;
 358   if (use_mojo_channel) {
 359     VLOG(1) << "Mojo is enabled on child";
 360     scoped_refptr<base::SequencedTaskRunner> io_task_runner = GetIOTaskRunner();
 361     DCHECK(io_task_runner);
 362     channel_->Init(
 363         IPC::ChannelMojo::CreateClientFactory(io_task_runner, channel_name_),
 364         create_pipe_now);
 365     return;
 366   }
 367
 368   VLOG(1) << "Mojo is disabled on child";
 369   channel_->Init(channel_name_, IPC::Channel::MODE_CLIENT, create_pipe_now);
 370 }
 371
 372 void ChildThreadImpl::Init(const Options& options) {
 373   channel_name_ = options.channel_name;
 374
 375   g_lazy_tls.Pointer()->Set(this);
 376   on_channel_error_called_ = false;
 377   message_loop_ = base::MessageLoop::current();
 378 #ifdef IPC_MESSAGE_LOG_ENABLED
 379   // We must make sure to instantiate the IPC Logger *before* we create the
 380   // channel, otherwise we can get a callback on the IO thread which creates
 381   // the logger, and the logger does not like being created on the IO thread.
 382   IPC::Logging::GetInstance();
 383 #endif
 384
 385 #if defined(OS_WIN)
 386   // The only reason a global would already exist is if the thread is being run
 387   // in the browser process because of a command line switch.
 388   if (!IPC::AttachmentBroker::GetGlobal()) {
 389     attachment_broker_.reset(new IPC::AttachmentBrokerUnprivilegedWin());
 390     IPC::AttachmentBroker::SetGlobal(attachment_broker_.get());
 391   }
 392 #endif
 393
 394   channel_ =
 395       IPC::SyncChannel::Create(this, ChildProcess::current()->io_task_runner(),
 396                                ChildProcess::current()->GetShutDownEvent());
 397 #ifdef IPC_MESSAGE_LOG_ENABLED
 398   if (!IsInBrowserProcess())
 399     IPC::Logging::GetInstance()->SetIPCSender(this);
 400 #endif
 401   // TODO(erikchen): Temporary code to help track http://crbug.com/527588.
 402   IPC::Channel::SetMessageVerifier(
 403       &content::CheckContentsOfDataReceivedMessage);
 404
 405   mojo_application_.reset(new MojoApplication(GetIOTaskRunner()));
 406
 407   sync_message_filter_ = channel_->CreateSyncMessageFilter();
 408   thread_safe_sender_ = new ThreadSafeSender(
 409       message_loop_->task_runner(), sync_message_filter_.get());
 410
 411   resource_dispatcher_.reset(new ResourceDispatcher(
 412       this, message_loop()->task_runner()));
 413   websocket_dispatcher_.reset(new WebSocketDispatcher);
 414   file_system_dispatcher_.reset(new FileSystemDispatcher());
 415
 416   histogram_message_filter_ = new ChildHistogramMessageFilter();
 417   resource_message_filter_ =
 418       new ChildResourceMessageFilter(resource_dispatcher());
 419
 420   service_worker_message_filter_ =
 421       new ServiceWorkerMessageFilter(thread_safe_sender_.get());
 422
 423   quota_message_filter_ =
 424       new QuotaMessageFilter(thread_safe_sender_.get());
 425   quota_dispatcher_.reset(new QuotaDispatcher(thread_safe_sender_.get(),
 426                                               quota_message_filter_.get()));
 427   geofencing_message_filter_ =
 428       new GeofencingMessageFilter(thread_safe_sender_.get());
 429   notification_dispatcher_ =
 430       new NotificationDispatcher(thread_safe_sender_.get());
 431   push_dispatcher_ = new PushDispatcher(thread_safe_sender_.get());
 432
 433   channel_->AddFilter(histogram_message_filter_.get());
 434   channel_->AddFilter(resource_message_filter_.get());
 435   channel_->AddFilter(quota_message_filter_->GetFilter());
 436   channel_->AddFilter(notification_dispatcher_->GetFilter());
 437   channel_->AddFilter(push_dispatcher_->GetFilter());
 438   channel_->AddFilter(service_worker_message_filter_->GetFilter());
 439   channel_->AddFilter(geofencing_message_filter_->GetFilter());
 440
 441   if (!IsInBrowserProcess()) {
 442     // In single process mode, browser-side tracing will cover the whole
 443     // process including renderers.
 444     channel_->AddFilter(new tracing::ChildTraceMessageFilter(
 445         ChildProcess::current()->io_task_runner()));
 446   }
 447
 448   // In single process mode we may already have a power monitor
 449   if (!base::PowerMonitor::Get()) {
 450     scoped_ptr<PowerMonitorBroadcastSource> power_monitor_source(
 451       new PowerMonitorBroadcastSource());
 452     channel_->AddFilter(power_monitor_source->GetMessageFilter());
 453
 454     power_monitor_.reset(new base::PowerMonitor(
 455         power_monitor_source.Pass()));
 456   }
 457
 458 #if defined(OS_POSIX)
 459   // Check that --process-type is specified so we don't do this in unit tests
 460   // and single-process mode.
 461   if (base::CommandLine::ForCurrentProcess()->HasSwitch(switches::kProcessType))
 462     channel_->AddFilter(new SuicideOnChannelErrorFilter());
 463 #endif
 464
 465 #if defined(OS_MACOSX)
 466   channel_->AddFilter(new IOSurfaceManagerFilter());
 467 #endif
 468
 469 #if defined(USE_OZONE)
 470   channel_->AddFilter(new ClientNativePixmapFactoryFilter());
 471 #endif
 472
 473   // Add filters passed here via options.
 474   for (auto startup_filter : options.startup_filters) {
 475     channel_->AddFilter(startup_filter);
 476   }
 477
 478   ConnectChannel(options.use_mojo_channel);
 479   if (attachment_broker_)
 480     attachment_broker_->DesignateBrokerCommunicationChannel(channel_.get());
 481
 482   int connection_timeout = kConnectionTimeoutS;
 483   std::string connection_override =
 484       base::CommandLine::ForCurrentProcess()->GetSwitchValueASCII(
 485           switches::kIPCConnectionTimeout);
 486   if (!connection_override.empty()) {
 487     int temp;
 488     if (base::StringToInt(connection_override, &temp))
 489       connection_timeout = temp;
 490   }
 491
 492   message_loop_->task_runner()->PostDelayedTask(
 493       FROM_HERE, base::Bind(&ChildThreadImpl::EnsureConnected,
 494                             channel_connected_factory_.GetWeakPtr()),
 495       base::TimeDelta::FromSeconds(connection_timeout));
 496
 497 #if defined(OS_ANDROID)
 498   g_quit_closure.Get().BindToMainThread();
 499 #endif
 500
 501 #if defined(TCMALLOC_TRACE_MEMORY_SUPPORTED)
 502   trace_memory_controller_.reset(new base::trace_event::TraceMemoryController(
 503       message_loop_->task_runner(), ::HeapProfilerWithPseudoStackStart,
 504       ::HeapProfilerStop, ::GetHeapProfile));
 505 #endif
 506
 507   shared_bitmap_manager_.reset(
 508       new ChildSharedBitmapManager(thread_safe_sender()));
 509
 510   gpu_memory_buffer_manager_.reset(
 511       new ChildGpuMemoryBufferManager(thread_safe_sender()));
 512
 513   discardable_shared_memory_manager_.reset(
 514       new ChildDiscardableSharedMemoryManager(thread_safe_sender()));
 515 }
 516
 517 ChildThreadImpl::~ChildThreadImpl() {
 518   // ChildDiscardableSharedMemoryManager has to be destroyed while
 519   // |thread_safe_sender_| is still valid.
 520   discardable_shared_memory_manager_.reset();
 521
 522 #ifdef IPC_MESSAGE_LOG_ENABLED
 523   IPC::Logging::GetInstance()->SetIPCSender(NULL);
 524 #endif
 525
 526   channel_->RemoveFilter(histogram_message_filter_.get());
 527   channel_->RemoveFilter(sync_message_filter_.get());
 528
 529   // The ChannelProxy object caches a pointer to the IPC thread, so need to
 530   // reset it as it's not guaranteed to outlive this object.
 531   // NOTE: this also has the side-effect of not closing the main IPC channel to
 532   // the browser process.  This is needed because this is the signal that the
 533   // browser uses to know that this process has died, so we need it to be alive
 534   // until this process is shut down, and the OS closes the handle
 535   // automatically.  We used to watch the object handle on Windows to do this,
 536   // but it wasn't possible to do so on POSIX.
 537   channel_->ClearIPCTaskRunner();
 538   g_lazy_tls.Pointer()->Set(NULL);
 539 }
 540
 541 void ChildThreadImpl::Shutdown() {
 542   // Delete objects that hold references to blink so derived classes can
 543   // safely shutdown blink in their Shutdown implementation.
 544   file_system_dispatcher_.reset();
 545   quota_dispatcher_.reset();
 546   WebFileSystemImpl::DeleteThreadSpecificInstance();
 547 }
 548
 549 void ChildThreadImpl::OnChannelConnected(int32 peer_pid) {
 550   channel_connected_factory_.InvalidateWeakPtrs();
 551 }
 552
 553 void ChildThreadImpl::OnChannelError() {
 554   set_on_channel_error_called(true);
 555   base::MessageLoop::current()->Quit();
 556 }
 557
 558 bool ChildThreadImpl::Send(IPC::Message* msg) {
 559   DCHECK(base::MessageLoop::current() == message_loop());
 560   if (!channel_) {
 561     delete msg;
 562     return false;
 563   }
 564
 565   return channel_->Send(msg);
 566 }
 567
 568 #if defined(OS_WIN)
 569 void ChildThreadImpl::PreCacheFont(const LOGFONT& log_font) {
 570   Send(new ChildProcessHostMsg_PreCacheFont(log_font));
 571 }
 572
 573 void ChildThreadImpl::ReleaseCachedFonts() {
 574   Send(new ChildProcessHostMsg_ReleaseCachedFonts());
 575 }
 576 #endif
 577
 578 MessageRouter* ChildThreadImpl::GetRouter() {
 579   DCHECK(base::MessageLoop::current() == message_loop());
 580   return &router_;
 581 }
 582
 583 scoped_ptr<base::SharedMemory> ChildThreadImpl::AllocateSharedMemory(
 584     size_t buf_size) {
 585   DCHECK(base::MessageLoop::current() == message_loop());
 586   return AllocateSharedMemory(buf_size, this);
 587 }
 588
 589 // static
 590 scoped_ptr<base::SharedMemory> ChildThreadImpl::AllocateSharedMemory(
 591     size_t buf_size,
 592     IPC::Sender* sender) {
 593   scoped_ptr<base::SharedMemory> shared_buf;
 594 #if defined(OS_WIN)
 595   shared_buf.reset(new base::SharedMemory);
 596   if (!shared_buf->CreateAnonymous(buf_size)) {
 597     NOTREACHED();
 598     return NULL;
 599   }
 600 #else
 601   // On POSIX, we need to ask the browser to create the shared memory for us,
 602   // since this is blocked by the sandbox.
 603   base::SharedMemoryHandle shared_mem_handle;
 604   if (sender->Send(new ChildProcessHostMsg_SyncAllocateSharedMemory(
 605                            buf_size, &shared_mem_handle))) {
 606     if (base::SharedMemory::IsHandleValid(shared_mem_handle)) {
 607       shared_buf.reset(new base::SharedMemory(shared_mem_handle, false));
 608     } else {
 609       NOTREACHED() << "Browser failed to allocate shared memory";
 610       return NULL;
 611     }
 612   } else {
 613     NOTREACHED() << "Browser allocation request message failed";
 614     return NULL;
 615   }
 616 #endif
 617   return shared_buf;
 618 }
 619
 620 bool ChildThreadImpl::OnMessageReceived(const IPC::Message& msg) {
 621   if (mojo_application_->OnMessageReceived(msg))
 622     return true;
 623
 624   // Resource responses are sent to the resource dispatcher.
 625   if (resource_dispatcher_->OnMessageReceived(msg))
 626     return true;
 627   if (websocket_dispatcher_->OnMessageReceived(msg))
 628     return true;
 629   if (file_system_dispatcher_->OnMessageReceived(msg))
 630     return true;
 631
 632   bool handled = true;
 633   IPC_BEGIN_MESSAGE_MAP(ChildThreadImpl, msg)
 634     IPC_MESSAGE_HANDLER(ChildProcessMsg_Shutdown, OnShutdown)
 635 #if defined(IPC_MESSAGE_LOG_ENABLED)
 636     IPC_MESSAGE_HANDLER(ChildProcessMsg_SetIPCLoggingEnabled,
 637                         OnSetIPCLoggingEnabled)
 638 #endif
 639     IPC_MESSAGE_HANDLER(ChildProcessMsg_SetProfilerStatus,
 640                         OnSetProfilerStatus)
 641     IPC_MESSAGE_HANDLER(ChildProcessMsg_GetChildProfilerData,
 642                         OnGetChildProfilerData)
 643     IPC_MESSAGE_HANDLER(ChildProcessMsg_ProfilingPhaseCompleted,
 644                         OnProfilingPhaseCompleted)
 645     IPC_MESSAGE_HANDLER(ChildProcessMsg_SetProcessBackgrounded,
 646                         OnProcessBackgrounded)
 647 #if defined(USE_TCMALLOC)
 648     IPC_MESSAGE_HANDLER(ChildProcessMsg_GetTcmallocStats, OnGetTcmallocStats)
 649 #endif
 650     IPC_MESSAGE_UNHANDLED(handled = false)
 651   IPC_END_MESSAGE_MAP()
 652
 653   if (handled)
 654     return true;
 655
 656   if (msg.routing_id() == MSG_ROUTING_CONTROL)
 657     return OnControlMessageReceived(msg);
 658
 659   return router_.OnMessageReceived(msg);
 660 }
 661
 662 bool ChildThreadImpl::OnControlMessageReceived(const IPC::Message& msg) {
 663   return false;
 664 }
 665
 666 void ChildThreadImpl::OnProcessBackgrounded(bool backgrounded) {
 667   // Set timer slack to maximum on main thread when in background.
 668   base::TimerSlack timer_slack = base::TIMER_SLACK_NONE;
 669   if (backgrounded)
 670     timer_slack = base::TIMER_SLACK_MAXIMUM;
 671   base::MessageLoop::current()->SetTimerSlack(timer_slack);
 672 }
 673
 674 void ChildThreadImpl::OnShutdown() {
 675   base::MessageLoop::current()->Quit();
 676 }
 677
 678 #if defined(IPC_MESSAGE_LOG_ENABLED)
 679 void ChildThreadImpl::OnSetIPCLoggingEnabled(bool enable) {
 680   if (enable)
 681     IPC::Logging::GetInstance()->Enable();
 682   else
 683     IPC::Logging::GetInstance()->Disable();
 684 }
 685 #endif  //  IPC_MESSAGE_LOG_ENABLED
 686
 687 void ChildThreadImpl::OnSetProfilerStatus(ThreadData::Status status) {
 688   ThreadData::InitializeAndSetTrackingStatus(status);
 689 }
 690
 691 void ChildThreadImpl::OnGetChildProfilerData(int sequence_number,
 692                                              int current_profiling_phase) {
 693   tracked_objects::ProcessDataSnapshot process_data;
 694   ThreadData::Snapshot(current_profiling_phase, &process_data);
 695
 696   Send(
 697       new ChildProcessHostMsg_ChildProfilerData(sequence_number, process_data));
 698 }
 699
 700 void ChildThreadImpl::OnProfilingPhaseCompleted(int profiling_phase) {
 701   ThreadData::OnProfilingPhaseCompleted(profiling_phase);
 702 }
 703
 704 #if defined(USE_TCMALLOC)
 705 void ChildThreadImpl::OnGetTcmallocStats() {
 706   std::string result;
 707   char buffer[1024 * 32];
 708   base::allocator::GetStats(buffer, sizeof(buffer));
 709   result.append(buffer);
 710   Send(new ChildProcessHostMsg_TcmallocStats(result));
 711 }
 712 #endif
 713
 714 ChildThreadImpl* ChildThreadImpl::current() {
 715   return g_lazy_tls.Pointer()->Get();
 716 }
 717
 718 #if defined(OS_ANDROID)
 719 // The method must NOT be called on the child thread itself.
 720 // It may block the child thread if so.
 721 void ChildThreadImpl::ShutdownThread() {
 722   DCHECK(!ChildThreadImpl::current()) <<
 723       "this method should NOT be called from child thread itself";
 724   g_quit_closure.Get().PostQuitFromNonMainThread();
 725 }
 726 #endif
 727
 728 void ChildThreadImpl::OnProcessFinalRelease() {
 729   if (on_channel_error_called_) {
 730     base::MessageLoop::current()->Quit();
 731     return;
 732   }
 733
 734   // The child process shutdown sequence is a request response based mechanism,
 735   // where we send out an initial feeler request to the child process host
 736   // instance in the browser to verify if it's ok to shutdown the child process.
 737   // The browser then sends back a response if it's ok to shutdown. This avoids
 738   // race conditions if the process refcount is 0 but there's an IPC message
 739   // inflight that would addref it.
 740   Send(new ChildProcessHostMsg_ShutdownRequest);
 741 }
 742
 743 void ChildThreadImpl::EnsureConnected() {
 744   VLOG(0) << "ChildThreadImpl::EnsureConnected()";
 745   base::Process::Current().Terminate(0, false);
 746 }
 747
 748 bool ChildThreadImpl::IsInBrowserProcess() const {
 749   return browser_process_io_runner_;
 750 }
 751
 752 }  // namespace content