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/lazy_instance.h"
  17 #include "base/logging.h"
  18 #include "base/message_loop/message_loop.h"
  19 #include "base/message_loop/timer_slack.h"
  20 #include "base/metrics/field_trial.h"
  21 #include "base/process/process.h"
  22 #include "base/process/process_handle.h"
  23 #include "base/strings/string_number_conversions.h"
  24 #include "base/strings/string_util.h"
  25 #include "base/synchronization/condition_variable.h"
  26 #include "base/synchronization/lock.h"
  27 #include "base/threading/thread_local.h"
  28 #include "base/tracked_objects.h"
  29 #include "components/tracing/child_trace_message_filter.h"
  30 #include "content/child/bluetooth/bluetooth_message_filter.h"
  31 #include "content/child/child_discardable_shared_memory_manager.h"
  32 #include "content/child/child_gpu_memory_buffer_manager.h"
  33 #include "content/child/child_histogram_message_filter.h"
  34 #include "content/child/child_process.h"
  35 #include "content/child/child_resource_message_filter.h"
  36 #include "content/child/child_shared_bitmap_manager.h"
  37 #include "content/child/fileapi/file_system_dispatcher.h"
  38 #include "content/child/fileapi/webfilesystem_impl.h"
  39 #include "content/child/geofencing/geofencing_message_filter.h"
  40 #include "content/child/mojo/mojo_application.h"
  41 #include "content/child/navigator_connect/navigator_connect_dispatcher.h"
  42 #include "content/child/notifications/notification_dispatcher.h"
  43 #include "content/child/power_monitor_broadcast_source.h"
  44 #include "content/child/push_messaging/push_dispatcher.h"
  45 #include "content/child/quota_dispatcher.h"
  46 #include "content/child/quota_message_filter.h"
  47 #include "content/child/resource_dispatcher.h"
  48 #include "content/child/service_worker/service_worker_message_filter.h"
  49 #include "content/child/thread_safe_sender.h"
  50 #include "content/child/websocket_dispatcher.h"
  51 #include "content/common/child_process_messages.h"
  52 #include "content/common/in_process_child_thread_params.h"
  53 #include "content/public/common/content_switches.h"
  54 #include "ipc/ipc_logging.h"
  55 #include "ipc/ipc_switches.h"
  56 #include "ipc/ipc_sync_channel.h"
  57 #include "ipc/ipc_sync_message_filter.h"
  58 #include "ipc/mojo/ipc_channel_mojo.h"
  59
  60 #if defined(OS_WIN)
  61 #include "content/common/handle_enumerator_win.h"
  62 #endif
  63
  64 #if defined(TCMALLOC_TRACE_MEMORY_SUPPORTED)
  65 #include "third_party/tcmalloc/chromium/src/gperftools/heap-profiler.h"
  66 #endif
  67
  68 using tracked_objects::ThreadData;
  69
  70 namespace content {
  71 namespace {
  72
  73 // How long to wait for a connection to the browser process before giving up.
  74 const int kConnectionTimeoutS = 15;
  75
  76 base::LazyInstance<base::ThreadLocalPointer<ChildThreadImpl> > g_lazy_tls =
  77     LAZY_INSTANCE_INITIALIZER;
  78
  79 // This isn't needed on Windows because there the sandbox's job object
  80 // terminates child processes automatically. For unsandboxed processes (i.e.
  81 // plugins), PluginThread has EnsureTerminateMessageFilter.
  82 #if defined(OS_POSIX)
  83
  84 #if defined(ADDRESS_SANITIZER) || defined(LEAK_SANITIZER) || \
  85     defined(MEMORY_SANITIZER) || defined(THREAD_SANITIZER) || \
  86     defined(UNDEFINED_SANITIZER)
  87 // A thread delegate that waits for |duration| and then exits the process with
  88 // _exit(0).
  89 class WaitAndExitDelegate : public base::PlatformThread::Delegate {
  90  public:
  91   explicit WaitAndExitDelegate(base::TimeDelta duration)
  92       : duration_(duration) {}
  93
  94   void ThreadMain() override {
  95     base::PlatformThread::Sleep(duration_);
  96     _exit(0);
  97   }
  98
  99  private:
 100   const base::TimeDelta duration_;
 101   DISALLOW_COPY_AND_ASSIGN(WaitAndExitDelegate);
 102 };
 103
 104 bool CreateWaitAndExitThread(base::TimeDelta duration) {
 105   scoped_ptr<WaitAndExitDelegate> delegate(new WaitAndExitDelegate(duration));
 106
 107   const bool thread_created =
 108       base::PlatformThread::CreateNonJoinable(0, delegate.get());
 109   if (!thread_created)
 110     return false;
 111
 112   // A non joinable thread has been created. The thread will either terminate
 113   // the process or will be terminated by the process. Therefore, keep the
 114   // delegate object alive for the lifetime of the process.
 115   WaitAndExitDelegate* leaking_delegate = delegate.release();
 116   ANNOTATE_LEAKING_OBJECT_PTR(leaking_delegate);
 117   ignore_result(leaking_delegate);
 118   return true;
 119 }
 120 #endif
 121
 122 class SuicideOnChannelErrorFilter : public IPC::MessageFilter {
 123  public:
 124   // IPC::MessageFilter
 125   void OnChannelError() override {
 126     // For renderer/worker processes:
 127     // On POSIX, at least, one can install an unload handler which loops
 128     // forever and leave behind a renderer process which eats 100% CPU forever.
 129     //
 130     // This is because the terminate signals (ViewMsg_ShouldClose and the error
 131     // from the IPC sender) are routed to the main message loop but never
 132     // processed (because that message loop is stuck in V8).
 133     //
 134     // One could make the browser SIGKILL the renderers, but that leaves open a
 135     // large window where a browser failure (or a user, manually terminating
 136     // the browser because "it's stuck") will leave behind a process eating all
 137     // the CPU.
 138     //
 139     // So, we install a filter on the sender so that we can process this event
 140     // here and kill the process.
 141 #if defined(ADDRESS_SANITIZER) || defined(LEAK_SANITIZER) || \
 142     defined(MEMORY_SANITIZER) || defined(THREAD_SANITIZER) || \
 143     defined(UNDEFINED_SANITIZER)
 144     // Some sanitizer tools rely on exit handlers (e.g. to run leak detection,
 145     // or dump code coverage data to disk). Instead of exiting the process
 146     // immediately, we give it 60 seconds to run exit handlers.
 147     CHECK(CreateWaitAndExitThread(base::TimeDelta::FromSeconds(60)));
 148 #if defined(LEAK_SANITIZER)
 149     // Invoke LeakSanitizer early to avoid detecting shutdown-only leaks. If
 150     // leaks are found, the process will exit here.
 151     __lsan_do_leak_check();
 152 #endif
 153 #else
 154     _exit(0);
 155 #endif
 156   }
 157
 158  protected:
 159   ~SuicideOnChannelErrorFilter() override {}
 160 };
 161
 162 #endif  // OS(POSIX)
 163
 164 #if defined(OS_ANDROID)
 165 ChildThreadImpl* g_child_thread = NULL;
 166 bool g_child_thread_initialized = false;
 167
 168 // A lock protects g_child_thread.
 169 base::LazyInstance<base::Lock>::Leaky g_lazy_child_thread_lock =
 170     LAZY_INSTANCE_INITIALIZER;
 171
 172 // base::ConditionVariable has an explicit constructor that takes
 173 // a base::Lock pointer as parameter. The base::DefaultLazyInstanceTraits
 174 // doesn't handle the case. Thus, we need our own class here.
 175 struct CondVarLazyInstanceTraits {
 176   static const bool kRegisterOnExit = false;
 177 #ifndef NDEBUG
 178   static const bool kAllowedToAccessOnNonjoinableThread = true;
 179 #endif
 180
 181   static base::ConditionVariable* New(void* instance) {
 182     return new (instance) base::ConditionVariable(
 183         g_lazy_child_thread_lock.Pointer());
 184   }
 185   static void Delete(base::ConditionVariable* instance) {
 186     instance->~ConditionVariable();
 187   }
 188 };
 189
 190 // A condition variable that synchronize threads initializing and waiting
 191 // for g_child_thread.
 192 base::LazyInstance<base::ConditionVariable, CondVarLazyInstanceTraits>
 193     g_lazy_child_thread_cv = LAZY_INSTANCE_INITIALIZER;
 194
 195 void QuitMainThreadMessageLoop() {
 196   base::MessageLoop::current()->Quit();
 197 }
 198
 199 #endif
 200
 201 }  // namespace
 202
 203 ChildThread* ChildThread::Get() {
 204   return ChildThreadImpl::current();
 205 }
 206
 207 ChildThreadImpl::Options::Options()
 208     : channel_name(base::CommandLine::ForCurrentProcess()->GetSwitchValueASCII(
 209           switches::kProcessChannelID)),
 210       use_mojo_channel(false) {
 211 }
 212
 213 ChildThreadImpl::Options::~Options() {
 214 }
 215
 216 ChildThreadImpl::Options::Builder::Builder() {
 217 }
 218
 219 ChildThreadImpl::Options::Builder&
 220 ChildThreadImpl::Options::Builder::InBrowserProcess(
 221     const InProcessChildThreadParams& params) {
 222   options_.browser_process_io_runner = params.io_runner();
 223   options_.channel_name = params.channel_name();
 224   return *this;
 225 }
 226
 227 ChildThreadImpl::Options::Builder&
 228 ChildThreadImpl::Options::Builder::UseMojoChannel(bool use_mojo_channel) {
 229   options_.use_mojo_channel = use_mojo_channel;
 230   return *this;
 231 }
 232
 233 ChildThreadImpl::Options::Builder&
 234 ChildThreadImpl::Options::Builder::WithChannelName(
 235     const std::string& channel_name) {
 236   options_.channel_name = channel_name;
 237   return *this;
 238 }
 239
 240 ChildThreadImpl::Options::Builder&
 241 ChildThreadImpl::Options::Builder::AddStartupFilter(
 242     IPC::MessageFilter* filter) {
 243   options_.startup_filters.push_back(filter);
 244   return *this;
 245 }
 246
 247 ChildThreadImpl::Options ChildThreadImpl::Options::Builder::Build() {
 248   return options_;
 249 }
 250
 251 ChildThreadImpl::ChildThreadMessageRouter::ChildThreadMessageRouter(
 252     IPC::Sender* sender)
 253     : sender_(sender) {}
 254
 255 bool ChildThreadImpl::ChildThreadMessageRouter::Send(IPC::Message* msg) {
 256   return sender_->Send(msg);
 257 }
 258
 259 ChildThreadImpl::ChildThreadImpl()
 260     : router_(this),
 261       channel_connected_factory_(this) {
 262   Init(Options::Builder().Build());
 263 }
 264
 265 ChildThreadImpl::ChildThreadImpl(const Options& options)
 266     : router_(this),
 267       browser_process_io_runner_(options.browser_process_io_runner),
 268       channel_connected_factory_(this) {
 269   Init(options);
 270 }
 271
 272 scoped_refptr<base::SequencedTaskRunner> ChildThreadImpl::GetIOTaskRunner() {
 273   if (IsInBrowserProcess())
 274     return browser_process_io_runner_;
 275   return ChildProcess::current()->io_message_loop_proxy();
 276 }
 277
 278 void ChildThreadImpl::ConnectChannel(bool use_mojo_channel) {
 279   bool create_pipe_now = true;
 280   if (use_mojo_channel) {
 281     VLOG(1) << "Mojo is enabled on child";
 282     scoped_refptr<base::SequencedTaskRunner> io_task_runner = GetIOTaskRunner();
 283     DCHECK(io_task_runner);
 284     channel_->Init(IPC::ChannelMojo::CreateClientFactory(
 285                        nullptr, io_task_runner, channel_name_),
 286                    create_pipe_now);
 287     return;
 288   }
 289
 290   VLOG(1) << "Mojo is disabled on child";
 291   channel_->Init(channel_name_, IPC::Channel::MODE_CLIENT, create_pipe_now);
 292 }
 293
 294 void ChildThreadImpl::Init(const Options& options) {
 295   channel_name_ = options.channel_name;
 296
 297   g_lazy_tls.Pointer()->Set(this);
 298   on_channel_error_called_ = false;
 299   message_loop_ = base::MessageLoop::current();
 300 #ifdef IPC_MESSAGE_LOG_ENABLED
 301   // We must make sure to instantiate the IPC Logger *before* we create the
 302   // channel, otherwise we can get a callback on the IO thread which creates
 303   // the logger, and the logger does not like being created on the IO thread.
 304   IPC::Logging::GetInstance();
 305 #endif
 306   channel_ = IPC::SyncChannel::Create(
 307       this, ChildProcess::current()->io_message_loop_proxy(),
 308       ChildProcess::current()->GetShutDownEvent());
 309 #ifdef IPC_MESSAGE_LOG_ENABLED
 310   if (!IsInBrowserProcess())
 311     IPC::Logging::GetInstance()->SetIPCSender(this);
 312 #endif
 313
 314   mojo_application_.reset(new MojoApplication(GetIOTaskRunner()));
 315
 316   sync_message_filter_ =
 317       new IPC::SyncMessageFilter(ChildProcess::current()->GetShutDownEvent());
 318   thread_safe_sender_ = new ThreadSafeSender(
 319       base::MessageLoopProxy::current().get(), sync_message_filter_.get());
 320
 321   resource_dispatcher_.reset(new ResourceDispatcher(
 322       this, message_loop()->task_runner()));
 323   websocket_dispatcher_.reset(new WebSocketDispatcher);
 324   file_system_dispatcher_.reset(new FileSystemDispatcher());
 325
 326   histogram_message_filter_ = new ChildHistogramMessageFilter();
 327   resource_message_filter_ =
 328       new ChildResourceMessageFilter(resource_dispatcher());
 329
 330   service_worker_message_filter_ =
 331       new ServiceWorkerMessageFilter(thread_safe_sender_.get());
 332
 333   quota_message_filter_ =
 334       new QuotaMessageFilter(thread_safe_sender_.get());
 335   quota_dispatcher_.reset(new QuotaDispatcher(thread_safe_sender_.get(),
 336                                               quota_message_filter_.get()));
 337   geofencing_message_filter_ =
 338       new GeofencingMessageFilter(thread_safe_sender_.get());
 339   bluetooth_message_filter_ =
 340       new BluetoothMessageFilter(thread_safe_sender_.get());
 341   notification_dispatcher_ =
 342       new NotificationDispatcher(thread_safe_sender_.get());
 343   push_dispatcher_ = new PushDispatcher(thread_safe_sender_.get());
 344   navigator_connect_dispatcher_ =
 345       new NavigatorConnectDispatcher(thread_safe_sender_.get());
 346
 347   channel_->AddFilter(histogram_message_filter_.get());
 348   channel_->AddFilter(sync_message_filter_.get());
 349   channel_->AddFilter(resource_message_filter_.get());
 350   channel_->AddFilter(quota_message_filter_->GetFilter());
 351   channel_->AddFilter(notification_dispatcher_->GetFilter());
 352   channel_->AddFilter(push_dispatcher_->GetFilter());
 353   channel_->AddFilter(service_worker_message_filter_->GetFilter());
 354   channel_->AddFilter(geofencing_message_filter_->GetFilter());
 355   channel_->AddFilter(bluetooth_message_filter_->GetFilter());
 356   channel_->AddFilter(navigator_connect_dispatcher_->GetFilter());
 357
 358   if (!IsInBrowserProcess()) {
 359     // In single process mode, browser-side tracing will cover the whole
 360     // process including renderers.
 361     channel_->AddFilter(new tracing::ChildTraceMessageFilter(
 362         ChildProcess::current()->io_message_loop_proxy()));
 363   }
 364
 365   // In single process mode we may already have a power monitor
 366   if (!base::PowerMonitor::Get()) {
 367     scoped_ptr<PowerMonitorBroadcastSource> power_monitor_source(
 368       new PowerMonitorBroadcastSource());
 369     channel_->AddFilter(power_monitor_source->GetMessageFilter());
 370
 371     power_monitor_.reset(new base::PowerMonitor(
 372         power_monitor_source.Pass()));
 373   }
 374
 375 #if defined(OS_POSIX)
 376   // Check that --process-type is specified so we don't do this in unit tests
 377   // and single-process mode.
 378   if (base::CommandLine::ForCurrentProcess()->HasSwitch(switches::kProcessType))
 379     channel_->AddFilter(new SuicideOnChannelErrorFilter());
 380 #endif
 381
 382   // Add filters passed here via options.
 383   for (auto startup_filter : options.startup_filters) {
 384     channel_->AddFilter(startup_filter);
 385   }
 386
 387   ConnectChannel(options.use_mojo_channel);
 388
 389   int connection_timeout = kConnectionTimeoutS;
 390   std::string connection_override =
 391       base::CommandLine::ForCurrentProcess()->GetSwitchValueASCII(
 392           switches::kIPCConnectionTimeout);
 393   if (!connection_override.empty()) {
 394     int temp;
 395     if (base::StringToInt(connection_override, &temp))
 396       connection_timeout = temp;
 397   }
 398
 399   base::MessageLoop::current()->PostDelayedTask(
 400       FROM_HERE,
 401       base::Bind(&ChildThreadImpl::EnsureConnected,
 402                  channel_connected_factory_.GetWeakPtr()),
 403       base::TimeDelta::FromSeconds(connection_timeout));
 404
 405 #if defined(OS_ANDROID)
 406   {
 407     base::AutoLock lock(g_lazy_child_thread_lock.Get());
 408     g_child_thread = this;
 409     g_child_thread_initialized = true;
 410   }
 411   // Signalling without locking is fine here because only
 412   // one thread can wait on the condition variable.
 413   g_lazy_child_thread_cv.Get().Signal();
 414 #endif
 415
 416 #if defined(TCMALLOC_TRACE_MEMORY_SUPPORTED)
 417   trace_memory_controller_.reset(new base::trace_event::TraceMemoryController(
 418       message_loop_->message_loop_proxy(), ::HeapProfilerWithPseudoStackStart,
 419       ::HeapProfilerStop, ::GetHeapProfile));
 420 #endif
 421
 422   shared_bitmap_manager_.reset(
 423       new ChildSharedBitmapManager(thread_safe_sender()));
 424
 425   gpu_memory_buffer_manager_.reset(
 426       new ChildGpuMemoryBufferManager(thread_safe_sender()));
 427
 428   discardable_shared_memory_manager_.reset(
 429       new ChildDiscardableSharedMemoryManager(thread_safe_sender()));
 430 }
 431
 432 ChildThreadImpl::~ChildThreadImpl() {
 433   // ChildDiscardableSharedMemoryManager has to be destroyed while
 434   // |thread_safe_sender_| is still valid.
 435   discardable_shared_memory_manager_.reset();
 436
 437 #if defined(OS_ANDROID)
 438   {
 439     base::AutoLock lock(g_lazy_child_thread_lock.Get());
 440     g_child_thread = nullptr;
 441   }
 442 #endif
 443
 444 #ifdef IPC_MESSAGE_LOG_ENABLED
 445   IPC::Logging::GetInstance()->SetIPCSender(NULL);
 446 #endif
 447
 448   channel_->RemoveFilter(histogram_message_filter_.get());
 449   channel_->RemoveFilter(sync_message_filter_.get());
 450
 451   // The ChannelProxy object caches a pointer to the IPC thread, so need to
 452   // reset it as it's not guaranteed to outlive this object.
 453   // NOTE: this also has the side-effect of not closing the main IPC channel to
 454   // the browser process.  This is needed because this is the signal that the
 455   // browser uses to know that this process has died, so we need it to be alive
 456   // until this process is shut down, and the OS closes the handle
 457   // automatically.  We used to watch the object handle on Windows to do this,
 458   // but it wasn't possible to do so on POSIX.
 459   channel_->ClearIPCTaskRunner();
 460   g_lazy_tls.Pointer()->Set(NULL);
 461 }
 462
 463 void ChildThreadImpl::Shutdown() {
 464   // Delete objects that hold references to blink so derived classes can
 465   // safely shutdown blink in their Shutdown implementation.
 466   file_system_dispatcher_.reset();
 467   quota_dispatcher_.reset();
 468   WebFileSystemImpl::DeleteThreadSpecificInstance();
 469 }
 470
 471 void ChildThreadImpl::OnChannelConnected(int32 peer_pid) {
 472   channel_connected_factory_.InvalidateWeakPtrs();
 473 }
 474
 475 void ChildThreadImpl::OnChannelError() {
 476   set_on_channel_error_called(true);
 477   base::MessageLoop::current()->Quit();
 478 }
 479
 480 bool ChildThreadImpl::Send(IPC::Message* msg) {
 481   DCHECK(base::MessageLoop::current() == message_loop());
 482   if (!channel_) {
 483     delete msg;
 484     return false;
 485   }
 486
 487   return channel_->Send(msg);
 488 }
 489
 490 #if defined(OS_WIN)
 491 void ChildThreadImpl::PreCacheFont(const LOGFONT& log_font) {
 492   Send(new ChildProcessHostMsg_PreCacheFont(log_font));
 493 }
 494
 495 void ChildThreadImpl::ReleaseCachedFonts() {
 496   Send(new ChildProcessHostMsg_ReleaseCachedFonts());
 497 }
 498 #endif
 499
 500 MessageRouter* ChildThreadImpl::GetRouter() {
 501   DCHECK(base::MessageLoop::current() == message_loop());
 502   return &router_;
 503 }
 504
 505 scoped_ptr<base::SharedMemory> ChildThreadImpl::AllocateSharedMemory(
 506     size_t buf_size) {
 507   DCHECK(base::MessageLoop::current() == message_loop());
 508   return AllocateSharedMemory(buf_size, this);
 509 }
 510
 511 // static
 512 scoped_ptr<base::SharedMemory> ChildThreadImpl::AllocateSharedMemory(
 513     size_t buf_size,
 514     IPC::Sender* sender) {
 515   scoped_ptr<base::SharedMemory> shared_buf;
 516 #if defined(OS_WIN)
 517   shared_buf.reset(new base::SharedMemory);
 518   if (!shared_buf->CreateAnonymous(buf_size)) {
 519     NOTREACHED();
 520     return NULL;
 521   }
 522 #else
 523   // On POSIX, we need to ask the browser to create the shared memory for us,
 524   // since this is blocked by the sandbox.
 525   base::SharedMemoryHandle shared_mem_handle;
 526   if (sender->Send(new ChildProcessHostMsg_SyncAllocateSharedMemory(
 527                            buf_size, &shared_mem_handle))) {
 528     if (base::SharedMemory::IsHandleValid(shared_mem_handle)) {
 529       shared_buf.reset(new base::SharedMemory(shared_mem_handle, false));
 530     } else {
 531       NOTREACHED() << "Browser failed to allocate shared memory";
 532       return NULL;
 533     }
 534   } else {
 535     NOTREACHED() << "Browser allocation request message failed";
 536     return NULL;
 537   }
 538 #endif
 539   return shared_buf;
 540 }
 541
 542 bool ChildThreadImpl::OnMessageReceived(const IPC::Message& msg) {
 543   if (mojo_application_->OnMessageReceived(msg))
 544     return true;
 545
 546   // Resource responses are sent to the resource dispatcher.
 547   if (resource_dispatcher_->OnMessageReceived(msg))
 548     return true;
 549   if (websocket_dispatcher_->OnMessageReceived(msg))
 550     return true;
 551   if (file_system_dispatcher_->OnMessageReceived(msg))
 552     return true;
 553
 554   bool handled = true;
 555   IPC_BEGIN_MESSAGE_MAP(ChildThreadImpl, msg)
 556     IPC_MESSAGE_HANDLER(ChildProcessMsg_Shutdown, OnShutdown)
 557 #if defined(IPC_MESSAGE_LOG_ENABLED)
 558     IPC_MESSAGE_HANDLER(ChildProcessMsg_SetIPCLoggingEnabled,
 559                         OnSetIPCLoggingEnabled)
 560 #endif
 561     IPC_MESSAGE_HANDLER(ChildProcessMsg_SetProfilerStatus,
 562                         OnSetProfilerStatus)
 563     IPC_MESSAGE_HANDLER(ChildProcessMsg_GetChildProfilerData,
 564                         OnGetChildProfilerData)
 565     IPC_MESSAGE_HANDLER(ChildProcessMsg_DumpHandles, OnDumpHandles)
 566     IPC_MESSAGE_HANDLER(ChildProcessMsg_SetProcessBackgrounded,
 567                         OnProcessBackgrounded)
 568 #if defined(USE_TCMALLOC)
 569     IPC_MESSAGE_HANDLER(ChildProcessMsg_GetTcmallocStats, OnGetTcmallocStats)
 570 #endif
 571     IPC_MESSAGE_UNHANDLED(handled = false)
 572   IPC_END_MESSAGE_MAP()
 573
 574   if (handled)
 575     return true;
 576
 577   if (msg.routing_id() == MSG_ROUTING_CONTROL)
 578     return OnControlMessageReceived(msg);
 579
 580   return router_.OnMessageReceived(msg);
 581 }
 582
 583 bool ChildThreadImpl::OnControlMessageReceived(const IPC::Message& msg) {
 584   return false;
 585 }
 586
 587 void ChildThreadImpl::OnShutdown() {
 588   base::MessageLoop::current()->Quit();
 589 }
 590
 591 #if defined(IPC_MESSAGE_LOG_ENABLED)
 592 void ChildThreadImpl::OnSetIPCLoggingEnabled(bool enable) {
 593   if (enable)
 594     IPC::Logging::GetInstance()->Enable();
 595   else
 596     IPC::Logging::GetInstance()->Disable();
 597 }
 598 #endif  //  IPC_MESSAGE_LOG_ENABLED
 599
 600 void ChildThreadImpl::OnSetProfilerStatus(ThreadData::Status status) {
 601   ThreadData::InitializeAndSetTrackingStatus(status);
 602 }
 603
 604 void ChildThreadImpl::OnGetChildProfilerData(int sequence_number) {
 605   tracked_objects::ProcessDataSnapshot process_data;
 606   ThreadData::Snapshot(&process_data);
 607
 608   Send(
 609       new ChildProcessHostMsg_ChildProfilerData(sequence_number, process_data));
 610 }
 611
 612 void ChildThreadImpl::OnDumpHandles() {
 613 #if defined(OS_WIN)
 614   scoped_refptr<HandleEnumerator> handle_enum(
 615       new HandleEnumerator(
 616           base::CommandLine::ForCurrentProcess()->HasSwitch(
 617               switches::kAuditAllHandles)));
 618   handle_enum->EnumerateHandles();
 619   Send(new ChildProcessHostMsg_DumpHandlesDone);
 620 #else
 621   NOTIMPLEMENTED();
 622 #endif
 623 }
 624
 625 #if defined(USE_TCMALLOC)
 626 void ChildThreadImpl::OnGetTcmallocStats() {
 627   std::string result;
 628   char buffer[1024 * 32];
 629   base::allocator::GetStats(buffer, sizeof(buffer));
 630   result.append(buffer);
 631   Send(new ChildProcessHostMsg_TcmallocStats(result));
 632 }
 633 #endif
 634
 635 ChildThreadImpl* ChildThreadImpl::current() {
 636   return g_lazy_tls.Pointer()->Get();
 637 }
 638
 639 #if defined(OS_ANDROID)
 640 // The method must NOT be called on the child thread itself.
 641 // It may block the child thread if so.
 642 void ChildThreadImpl::ShutdownThread() {
 643   DCHECK(!ChildThreadImpl::current()) <<
 644       "this method should NOT be called from child thread itself";
 645   {
 646     base::AutoLock lock(g_lazy_child_thread_lock.Get());
 647     while (!g_child_thread_initialized)
 648       g_lazy_child_thread_cv.Get().Wait();
 649
 650     // g_child_thread may already have been destructed while we didn't hold the
 651     // lock.
 652     if (!g_child_thread)
 653       return;
 654
 655     DCHECK_NE(base::MessageLoop::current(), g_child_thread->message_loop());
 656     g_child_thread->message_loop()->PostTask(
 657         FROM_HERE, base::Bind(&QuitMainThreadMessageLoop));
 658   }
 659 }
 660 #endif
 661
 662 void ChildThreadImpl::OnProcessFinalRelease() {
 663   if (on_channel_error_called_) {
 664     base::MessageLoop::current()->Quit();
 665     return;
 666   }
 667
 668   // The child process shutdown sequence is a request response based mechanism,
 669   // where we send out an initial feeler request to the child process host
 670   // instance in the browser to verify if it's ok to shutdown the child process.
 671   // The browser then sends back a response if it's ok to shutdown. This avoids
 672   // race conditions if the process refcount is 0 but there's an IPC message
 673   // inflight that would addref it.
 674   Send(new ChildProcessHostMsg_ShutdownRequest);
 675 }
 676
 677 void ChildThreadImpl::EnsureConnected() {
 678   VLOG(0) << "ChildThreadImpl::EnsureConnected()";
 679   base::Process::Current().Terminate(0, false);
 680 }
 681
 682 bool ChildThreadImpl::IsInBrowserProcess() const {
 683   return browser_process_io_runner_;
 684 }
 685
 686 void ChildThreadImpl::OnProcessBackgrounded(bool background) {
 687   // Set timer slack to maximum on main thread when in background.
 688   base::TimerSlack timer_slack = base::TIMER_SLACK_NONE;
 689   if (background)
 690     timer_slack = base::TIMER_SLACK_MAXIMUM;
 691   base::MessageLoop::current()->SetTimerSlack(timer_slack);
 692
 693 #ifdef OS_WIN
 694   // Windows Vista+ has a fancy process backgrounding mode that can only be set
 695   // from within the process. This used to be how chrome set its renderers into
 696   // background mode on Windows but was removed due to http://crbug.com/398103.
 697   // As we experiment with bringing back some other form of background mode for
 698   // hidden renderers, add a bucket to allow us to trigger this undesired method
 699   // of setting background state in order to confirm that the metrics which were
 700   // added to prevent regressions on the aforementioned issue indeed catch such
 701   // regressions and are thus a reliable way to confirm that our latest proposal
 702   // doesn't cause such issues. TODO(gab): Remove this once the experiment is
 703   // over (http://crbug.com/458594).
 704   base::FieldTrial* trial =
 705       base::FieldTrialList::Find("BackgroundRendererProcesses");
 706   if (trial && trial->group_name() == "AllowBackgroundModeFromRenderer")
 707     base::Process::Current().SetProcessBackgrounded(background);
 708 #endif  // OS_WIN
 709 }
 710
 711 }  // namespace content