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