src/content/child/resource_dispatcher.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 // See http://dev.chromium.org/developers/design-documents/multi-process-resource-loading
   6
   7 #include "content/child/resource_dispatcher.h"
   8
   9 #include "base/basictypes.h"
  10 #include "base/bind.h"
  11 #include "base/compiler_specific.h"
  12 #include "base/debug/alias.h"
  13 #include "base/files/file_path.h"
  14 #include "base/memory/shared_memory.h"
  15 #include "base/message_loop/message_loop.h"
  16 #include "base/metrics/histogram.h"
  17 #include "base/strings/string_util.h"
  18 #include "content/child/request_extra_data.h"
  19 #include "content/child/request_info.h"
  20 #include "content/child/site_isolation_policy.h"
  21 #include "content/child/sync_load_response.h"
  22 #include "content/child/threaded_data_provider.h"
  23 #include "content/common/inter_process_time_ticks_converter.h"
  24 #include "content/common/resource_messages.h"
  25 #include "content/public/child/request_peer.h"
  26 #include "content/public/child/resource_dispatcher_delegate.h"
  27 #include "content/public/common/resource_response.h"
  28 #include "content/public/common/resource_type.h"
  29 #include "net/base/net_errors.h"
  30 #include "net/base/net_util.h"
  31 #include "net/base/request_priority.h"
  32 #include "net/http/http_response_headers.h"
  33 #include "webkit/child/resource_loader_bridge.h"
  34
  35 using webkit_glue::ResourceLoaderBridge;
  36
  37 namespace content {
  38
  39 namespace {
  40
  41 // Converts |time| from a remote to local TimeTicks, overwriting the original
  42 // value.
  43 void RemoteToLocalTimeTicks(
  44     const InterProcessTimeTicksConverter& converter,
  45     base::TimeTicks* time) {
  46   RemoteTimeTicks remote_time = RemoteTimeTicks::FromTimeTicks(*time);
  47   *time = converter.ToLocalTimeTicks(remote_time).ToTimeTicks();
  48 }
  49
  50 void CrashOnMapFailure() {
  51 #if defined(OS_WIN)
  52   DWORD last_err = GetLastError();
  53   base::debug::Alias(&last_err);
  54 #endif
  55   CHECK(false);
  56 }
  57
  58 // Each resource request is assigned an ID scoped to this process.
  59 int MakeRequestID() {
  60   // NOTE: The resource_dispatcher_host also needs probably unique
  61   // request_ids, so they count down from -2 (-1 is a special we're
  62   // screwed value), while the renderer process counts up.
  63   static int next_request_id = 0;
  64   return next_request_id++;
  65 }
  66
  67 }  // namespace
  68
  69 // ResourceLoaderBridge implementation ----------------------------------------
  70
  71 class IPCResourceLoaderBridge : public ResourceLoaderBridge {
  72  public:
  73   IPCResourceLoaderBridge(ResourceDispatcher* dispatcher,
  74                           const RequestInfo& request_info);
  75   virtual ~IPCResourceLoaderBridge();
  76
  77   // ResourceLoaderBridge
  78   virtual void SetRequestBody(ResourceRequestBody* request_body) OVERRIDE;
  79   virtual bool Start(RequestPeer* peer) OVERRIDE;
  80   virtual void Cancel() OVERRIDE;
  81   virtual void SetDefersLoading(bool value) OVERRIDE;
  82   virtual void DidChangePriority(net::RequestPriority new_priority,
  83                                  int intra_priority_value) OVERRIDE;
  84   virtual bool AttachThreadedDataReceiver(
  85       blink::WebThreadedDataReceiver* threaded_data_receiver) OVERRIDE;
  86   virtual void SyncLoad(SyncLoadResponse* response) OVERRIDE;
  87
  88  private:
  89   // The resource dispatcher for this loader.  The bridge doesn't own it, but
  90   // it's guaranteed to outlive the bridge.
  91   ResourceDispatcher* dispatcher_;
  92
  93   // The request to send, created on initialization for modification and
  94   // appending data.
  95   ResourceHostMsg_Request request_;
  96
  97   // ID for the request, valid once Start()ed, -1 if not valid yet.
  98   int request_id_;
  99
 100   // The routing id used when sending IPC messages.
 101   int routing_id_;
 102
 103   // The security origin of the frame that initiates this request.
 104   GURL frame_origin_;
 105
 106   bool is_synchronous_request_;
 107 };
 108
 109 IPCResourceLoaderBridge::IPCResourceLoaderBridge(
 110     ResourceDispatcher* dispatcher,
 111     const RequestInfo& request_info)
 112     : dispatcher_(dispatcher),
 113       request_id_(-1),
 114       routing_id_(request_info.routing_id),
 115       is_synchronous_request_(false) {
 116   DCHECK(dispatcher_) << "no resource dispatcher";
 117   request_.method = request_info.method;
 118   request_.url = request_info.url;
 119   request_.first_party_for_cookies = request_info.first_party_for_cookies;
 120   request_.referrer = request_info.referrer;
 121   request_.referrer_policy = request_info.referrer_policy;
 122   request_.headers = request_info.headers;
 123   request_.load_flags = request_info.load_flags;
 124   request_.origin_pid = request_info.requestor_pid;
 125   request_.resource_type = request_info.request_type;
 126   request_.priority = request_info.priority;
 127   request_.request_context = request_info.request_context;
 128   request_.appcache_host_id = request_info.appcache_host_id;
 129   request_.download_to_file = request_info.download_to_file;
 130   request_.has_user_gesture = request_info.has_user_gesture;
 131   request_.enable_load_timing = request_info.enable_load_timing;
 132
 133   const RequestExtraData kEmptyData;
 134   const RequestExtraData* extra_data;
 135   if (request_info.extra_data)
 136     extra_data = static_cast<RequestExtraData*>(request_info.extra_data);
 137   else
 138     extra_data = &kEmptyData;
 139   request_.visiblity_state = extra_data->visibility_state();
 140   request_.render_frame_id = extra_data->render_frame_id();
 141   request_.is_main_frame = extra_data->is_main_frame();
 142   request_.parent_is_main_frame = extra_data->parent_is_main_frame();
 143   request_.parent_render_frame_id = extra_data->parent_render_frame_id();
 144   request_.allow_download = extra_data->allow_download();
 145   request_.transition_type = extra_data->transition_type();
 146   request_.should_replace_current_entry =
 147       extra_data->should_replace_current_entry();
 148   request_.transferred_request_child_id =
 149       extra_data->transferred_request_child_id();
 150   request_.transferred_request_request_id =
 151       extra_data->transferred_request_request_id();
 152   request_.service_worker_provider_id =
 153       extra_data->service_worker_provider_id();
 154   frame_origin_ = extra_data->frame_origin();
 155 }
 156
 157 IPCResourceLoaderBridge::~IPCResourceLoaderBridge() {
 158   // we remove our hook for the resource dispatcher only when going away, since
 159   // it doesn't keep track of whether we've force terminated the request
 160   if (request_id_ >= 0) {
 161     // this operation may fail, as the dispatcher will have preemptively
 162     // removed us when the renderer sends the ReceivedAllData message.
 163     dispatcher_->RemovePendingRequest(request_id_);
 164   }
 165 }
 166
 167 void IPCResourceLoaderBridge::SetRequestBody(
 168     ResourceRequestBody* request_body) {
 169   DCHECK(request_id_ == -1) << "request already started";
 170   request_.request_body = request_body;
 171 }
 172
 173 // Writes a footer on the message and sends it
 174 bool IPCResourceLoaderBridge::Start(RequestPeer* peer) {
 175   if (request_id_ != -1) {
 176     NOTREACHED() << "Starting a request twice";
 177     return false;
 178   }
 179
 180   // generate the request ID, and append it to the message
 181   request_id_ = dispatcher_->AddPendingRequest(peer,
 182                                                request_.resource_type,
 183                                                request_.origin_pid,
 184                                                frame_origin_,
 185                                                request_.url,
 186                                                request_.download_to_file);
 187
 188   return dispatcher_->message_sender()->Send(
 189       new ResourceHostMsg_RequestResource(routing_id_, request_id_, request_));
 190 }
 191
 192 void IPCResourceLoaderBridge::Cancel() {
 193   if (request_id_ < 0) {
 194     NOTREACHED() << "Trying to cancel an unstarted request";
 195     return;
 196   }
 197
 198   if (!is_synchronous_request_) {
 199     // This also removes the the request from the dispatcher.
 200     dispatcher_->CancelPendingRequest(request_id_);
 201   }
 202 }
 203
 204 void IPCResourceLoaderBridge::SetDefersLoading(bool value) {
 205   if (request_id_ < 0) {
 206     NOTREACHED() << "Trying to (un)defer an unstarted request";
 207     return;
 208   }
 209
 210   dispatcher_->SetDefersLoading(request_id_, value);
 211 }
 212
 213 void IPCResourceLoaderBridge::DidChangePriority(
 214     net::RequestPriority new_priority,
 215     int intra_priority_value) {
 216   if (request_id_ < 0) {
 217     NOTREACHED() << "Trying to change priority of an unstarted request";
 218     return;
 219   }
 220
 221   dispatcher_->DidChangePriority(
 222       request_id_, new_priority, intra_priority_value);
 223 }
 224
 225 bool IPCResourceLoaderBridge::AttachThreadedDataReceiver(
 226     blink::WebThreadedDataReceiver* threaded_data_receiver) {
 227   if (request_id_ < 0) {
 228     NOTREACHED() << "Trying to attach threaded receiver on unstarted request";
 229     return false;
 230   }
 231
 232   return dispatcher_->AttachThreadedDataReceiver(request_id_,
 233                                                  threaded_data_receiver);
 234 }
 235
 236 void IPCResourceLoaderBridge::SyncLoad(SyncLoadResponse* response) {
 237   if (request_id_ != -1) {
 238     NOTREACHED() << "Starting a request twice";
 239     response->error_code = net::ERR_FAILED;
 240     return;
 241   }
 242
 243   request_id_ = MakeRequestID();
 244   is_synchronous_request_ = true;
 245
 246   SyncLoadResult result;
 247   IPC::SyncMessage* msg = new ResourceHostMsg_SyncLoad(routing_id_, request_id_,
 248                                                        request_, &result);
 249   // NOTE: This may pump events (see RenderThread::Send).
 250   if (!dispatcher_->message_sender()->Send(msg)) {
 251     response->error_code = net::ERR_FAILED;
 252     return;
 253   }
 254
 255   response->error_code = result.error_code;
 256   response->url = result.final_url;
 257   response->headers = result.headers;
 258   response->mime_type = result.mime_type;
 259   response->charset = result.charset;
 260   response->request_time = result.request_time;
 261   response->response_time = result.response_time;
 262   response->encoded_data_length = result.encoded_data_length;
 263   response->load_timing = result.load_timing;
 264   response->devtools_info = result.devtools_info;
 265   response->data.swap(result.data);
 266   response->download_file_path = result.download_file_path;
 267 }
 268
 269 // ResourceDispatcher ---------------------------------------------------------
 270
 271 ResourceDispatcher::ResourceDispatcher(IPC::Sender* sender)
 272     : message_sender_(sender),
 273       weak_factory_(this),
 274       delegate_(NULL),
 275       io_timestamp_(base::TimeTicks()) {
 276 }
 277
 278 ResourceDispatcher::~ResourceDispatcher() {
 279 }
 280
 281 // ResourceDispatcher implementation ------------------------------------------
 282
 283 bool ResourceDispatcher::OnMessageReceived(const IPC::Message& message) {
 284   if (!IsResourceDispatcherMessage(message)) {
 285     return false;
 286   }
 287
 288   int request_id;
 289
 290   PickleIterator iter(message);
 291   if (!message.ReadInt(&iter, &request_id)) {
 292     NOTREACHED() << "malformed resource message";
 293     return true;
 294   }
 295
 296   PendingRequestInfo* request_info = GetPendingRequestInfo(request_id);
 297   if (!request_info) {
 298     // Release resources in the message if it is a data message.
 299     ReleaseResourcesInDataMessage(message);
 300     return true;
 301   }
 302
 303   if (request_info->is_deferred) {
 304     request_info->deferred_message_queue.push_back(new IPC::Message(message));
 305     return true;
 306   }
 307   // Make sure any deferred messages are dispatched before we dispatch more.
 308   if (!request_info->deferred_message_queue.empty()) {
 309     FlushDeferredMessages(request_id);
 310     // The request could have been deferred now. If yes then the current
 311     // message has to be queued up. The request_info instance should remain
 312     // valid here as there are pending messages for it.
 313     DCHECK(pending_requests_.find(request_id) != pending_requests_.end());
 314     if (request_info->is_deferred) {
 315       request_info->deferred_message_queue.push_back(new IPC::Message(message));
 316       return true;
 317     }
 318   }
 319
 320   DispatchMessage(message);
 321   return true;
 322 }
 323
 324 ResourceDispatcher::PendingRequestInfo*
 325 ResourceDispatcher::GetPendingRequestInfo(int request_id) {
 326   PendingRequestList::iterator it = pending_requests_.find(request_id);
 327   if (it == pending_requests_.end()) {
 328     // This might happen for kill()ed requests on the webkit end.
 329     return NULL;
 330   }
 331   return &(it->second);
 332 }
 333
 334 void ResourceDispatcher::OnUploadProgress(int request_id, int64 position,
 335                                           int64 size) {
 336   PendingRequestInfo* request_info = GetPendingRequestInfo(request_id);
 337   if (!request_info)
 338     return;
 339
 340   request_info->peer->OnUploadProgress(position, size);
 341
 342   // Acknowledge receipt
 343   message_sender_->Send(new ResourceHostMsg_UploadProgress_ACK(request_id));
 344 }
 345
 346 void ResourceDispatcher::OnReceivedResponse(
 347     int request_id, const ResourceResponseHead& response_head) {
 348   TRACE_EVENT0("loader", "ResourceDispatcher::OnReceivedResponse");
 349   PendingRequestInfo* request_info = GetPendingRequestInfo(request_id);
 350   if (!request_info)
 351     return;
 352   request_info->response_start = ConsumeIOTimestamp();
 353
 354   if (delegate_) {
 355     RequestPeer* new_peer =
 356         delegate_->OnReceivedResponse(
 357             request_info->peer, response_head.mime_type, request_info->url);
 358     if (new_peer)
 359       request_info->peer = new_peer;
 360   }
 361
 362   // Updates the response_url if the response was fetched by a ServiceWorker,
 363   // and it was not generated inside the ServiceWorker.
 364   if (response_head.was_fetched_via_service_worker &&
 365       !response_head.original_url_via_service_worker.is_empty()) {
 366     request_info->response_url = response_head.original_url_via_service_worker;
 367   }
 368
 369   ResourceResponseInfo renderer_response_info;
 370   ToResourceResponseInfo(*request_info, response_head, &renderer_response_info);
 371   request_info->site_isolation_metadata =
 372       SiteIsolationPolicy::OnReceivedResponse(request_info->frame_origin,
 373                                               request_info->response_url,
 374                                               request_info->resource_type,
 375                                               request_info->origin_pid,
 376                                               renderer_response_info);
 377   request_info->peer->OnReceivedResponse(renderer_response_info);
 378 }
 379
 380 void ResourceDispatcher::OnReceivedCachedMetadata(
 381       int request_id, const std::vector<char>& data) {
 382   PendingRequestInfo* request_info = GetPendingRequestInfo(request_id);
 383   if (!request_info)
 384     return;
 385
 386   if (data.size())
 387     request_info->peer->OnReceivedCachedMetadata(&data.front(), data.size());
 388 }
 389
 390 void ResourceDispatcher::OnSetDataBuffer(int request_id,
 391                                          base::SharedMemoryHandle shm_handle,
 392                                          int shm_size,
 393                                          base::ProcessId renderer_pid) {
 394   TRACE_EVENT0("loader", "ResourceDispatcher::OnSetDataBuffer");
 395   PendingRequestInfo* request_info = GetPendingRequestInfo(request_id);
 396   if (!request_info)
 397     return;
 398
 399   bool shm_valid = base::SharedMemory::IsHandleValid(shm_handle);
 400   CHECK((shm_valid && shm_size > 0) || (!shm_valid && !shm_size));
 401
 402   request_info->buffer.reset(
 403       new base::SharedMemory(shm_handle, true));  // read only
 404
 405   bool ok = request_info->buffer->Map(shm_size);
 406   if (!ok) {
 407     // Added to help debug crbug/160401.
 408     base::ProcessId renderer_pid_copy = renderer_pid;
 409     base::debug::Alias(&renderer_pid_copy);
 410
 411     base::SharedMemoryHandle shm_handle_copy = shm_handle;
 412     base::debug::Alias(&shm_handle_copy);
 413
 414     CrashOnMapFailure();
 415     return;
 416   }
 417
 418   request_info->buffer_size = shm_size;
 419 }
 420
 421 void ResourceDispatcher::OnReceivedData(int request_id,
 422                                         int data_offset,
 423                                         int data_length,
 424                                         int encoded_data_length) {
 425   TRACE_EVENT0("loader", "ResourceDispatcher::OnReceivedData");
 426   DCHECK_GT(data_length, 0);
 427   PendingRequestInfo* request_info = GetPendingRequestInfo(request_id);
 428   bool send_ack = true;
 429   if (request_info && data_length > 0) {
 430     CHECK(base::SharedMemory::IsHandleValid(request_info->buffer->handle()));
 431     CHECK_GE(request_info->buffer_size, data_offset + data_length);
 432
 433     // Ensure that the SHM buffer remains valid for the duration of this scope.
 434     // It is possible for CancelPendingRequest() to be called before we exit
 435     // this scope.
 436     linked_ptr<base::SharedMemory> retain_buffer(request_info->buffer);
 437
 438     base::TimeTicks time_start = base::TimeTicks::Now();
 439
 440     const char* data_start = static_cast<char*>(request_info->buffer->memory());
 441     CHECK(data_start);
 442     CHECK(data_start + data_offset);
 443     const char* data_ptr = data_start + data_offset;
 444
 445     // Check whether this response data is compliant with our cross-site
 446     // document blocking policy. We only do this for the first packet.
 447     std::string alternative_data;
 448     if (request_info->site_isolation_metadata.get()) {
 449       request_info->blocked_response =
 450           SiteIsolationPolicy::ShouldBlockResponse(
 451               request_info->site_isolation_metadata, data_ptr, data_length,
 452               &alternative_data);
 453       request_info->site_isolation_metadata.reset();
 454
 455       // When the response is blocked we may have any alternative data to
 456       // send to the renderer. When |alternative_data| is zero-sized, we do not
 457       // call peer's callback.
 458       if (request_info->blocked_response && !alternative_data.empty()) {
 459         data_ptr = alternative_data.data();
 460         data_length = alternative_data.size();
 461         encoded_data_length = alternative_data.size();
 462       }
 463     }
 464
 465     if (!request_info->blocked_response || !alternative_data.empty()) {
 466       if (request_info->threaded_data_provider) {
 467         request_info->threaded_data_provider->OnReceivedDataOnForegroundThread(
 468             data_ptr, data_length, encoded_data_length);
 469         // A threaded data provider will take care of its own ACKing, as the
 470         // data may be processed later on another thread.
 471         send_ack = false;
 472       } else {
 473         request_info->peer->OnReceivedData(
 474             data_ptr, data_length, encoded_data_length);
 475       }
 476     }
 477
 478     UMA_HISTOGRAM_TIMES("ResourceDispatcher.OnReceivedDataTime",
 479                         base::TimeTicks::Now() - time_start);
 480   }
 481
 482   // Acknowledge the reception of this data.
 483   if (send_ack)
 484     message_sender_->Send(new ResourceHostMsg_DataReceived_ACK(request_id));
 485 }
 486
 487 void ResourceDispatcher::OnDownloadedData(int request_id,
 488                                           int data_len,
 489                                           int encoded_data_length) {
 490   // Acknowledge the reception of this message.
 491   message_sender_->Send(new ResourceHostMsg_DataDownloaded_ACK(request_id));
 492
 493   PendingRequestInfo* request_info = GetPendingRequestInfo(request_id);
 494   if (!request_info)
 495     return;
 496
 497   request_info->peer->OnDownloadedData(data_len, encoded_data_length);
 498 }
 499
 500 void ResourceDispatcher::OnReceivedRedirect(
 501     int request_id,
 502     const net::RedirectInfo& redirect_info,
 503     const ResourceResponseHead& response_head) {
 504   TRACE_EVENT0("loader", "ResourceDispatcher::OnReceivedRedirect");
 505   PendingRequestInfo* request_info = GetPendingRequestInfo(request_id);
 506   if (!request_info)
 507     return;
 508   request_info->response_start = ConsumeIOTimestamp();
 509
 510   ResourceResponseInfo renderer_response_info;
 511   ToResourceResponseInfo(*request_info, response_head, &renderer_response_info);
 512   if (request_info->peer->OnReceivedRedirect(redirect_info,
 513                                              renderer_response_info)) {
 514     // Double-check if the request is still around. The call above could
 515     // potentially remove it.
 516     request_info = GetPendingRequestInfo(request_id);
 517     if (!request_info)
 518       return;
 519     // We update the response_url here so that we can send it to
 520     // SiteIsolationPolicy later when OnReceivedResponse is called.
 521     request_info->response_url = redirect_info.new_url;
 522     request_info->pending_redirect_message.reset(
 523         new ResourceHostMsg_FollowRedirect(request_id));
 524     if (!request_info->is_deferred) {
 525       FollowPendingRedirect(request_id, *request_info);
 526     }
 527   } else {
 528     CancelPendingRequest(request_id);
 529   }
 530 }
 531
 532 void ResourceDispatcher::FollowPendingRedirect(
 533     int request_id,
 534     PendingRequestInfo& request_info) {
 535   IPC::Message* msg = request_info.pending_redirect_message.release();
 536   if (msg)
 537     message_sender_->Send(msg);
 538 }
 539
 540 void ResourceDispatcher::OnRequestComplete(
 541     int request_id,
 542     const ResourceMsg_RequestCompleteData& request_complete_data) {
 543   TRACE_EVENT0("loader", "ResourceDispatcher::OnRequestComplete");
 544
 545   PendingRequestInfo* request_info = GetPendingRequestInfo(request_id);
 546   if (!request_info)
 547     return;
 548   request_info->completion_time = ConsumeIOTimestamp();
 549   request_info->buffer.reset();
 550   request_info->buffer_size = 0;
 551
 552   RequestPeer* peer = request_info->peer;
 553
 554   if (delegate_) {
 555     RequestPeer* new_peer =
 556         delegate_->OnRequestComplete(
 557             request_info->peer, request_info->resource_type,
 558             request_complete_data.error_code);
 559     if (new_peer)
 560       request_info->peer = new_peer;
 561   }
 562
 563   base::TimeTicks renderer_completion_time = ToRendererCompletionTime(
 564       *request_info, request_complete_data.completion_time);
 565   // The request ID will be removed from our pending list in the destructor.
 566   // Normally, dispatching this message causes the reference-counted request to
 567   // die immediately.
 568   peer->OnCompletedRequest(request_complete_data.error_code,
 569                            request_complete_data.was_ignored_by_handler,
 570                            request_complete_data.exists_in_cache,
 571                            request_complete_data.security_info,
 572                            renderer_completion_time,
 573                            request_complete_data.encoded_data_length);
 574 }
 575
 576 int ResourceDispatcher::AddPendingRequest(RequestPeer* callback,
 577                                           ResourceType resource_type,
 578                                           int origin_pid,
 579                                           const GURL& frame_origin,
 580                                           const GURL& request_url,
 581                                           bool download_to_file) {
 582   // Compute a unique request_id for this renderer process.
 583   int id = MakeRequestID();
 584   pending_requests_[id] = PendingRequestInfo(callback,
 585                                              resource_type,
 586                                              origin_pid,
 587                                              frame_origin,
 588                                              request_url,
 589                                              download_to_file);
 590   return id;
 591 }
 592
 593 bool ResourceDispatcher::RemovePendingRequest(int request_id) {
 594   PendingRequestList::iterator it = pending_requests_.find(request_id);
 595   if (it == pending_requests_.end())
 596     return false;
 597
 598   PendingRequestInfo& request_info = it->second;
 599
 600   bool release_downloaded_file = request_info.download_to_file;
 601
 602   ReleaseResourcesInMessageQueue(&request_info.deferred_message_queue);
 603   pending_requests_.erase(it);
 604
 605   if (release_downloaded_file) {
 606     message_sender_->Send(
 607         new ResourceHostMsg_ReleaseDownloadedFile(request_id));
 608   }
 609
 610   return true;
 611 }
 612
 613 void ResourceDispatcher::CancelPendingRequest(int request_id) {
 614   PendingRequestList::iterator it = pending_requests_.find(request_id);
 615   if (it == pending_requests_.end()) {
 616     DVLOG(1) << "unknown request";
 617     return;
 618   }
 619
 620   // Cancel the request, and clean it up so the bridge will receive no more
 621   // messages.
 622   message_sender_->Send(new ResourceHostMsg_CancelRequest(request_id));
 623   RemovePendingRequest(request_id);
 624 }
 625
 626 void ResourceDispatcher::SetDefersLoading(int request_id, bool value) {
 627   PendingRequestList::iterator it = pending_requests_.find(request_id);
 628   if (it == pending_requests_.end()) {
 629     DLOG(ERROR) << "unknown request";
 630     return;
 631   }
 632   PendingRequestInfo& request_info = it->second;
 633   if (value) {
 634     request_info.is_deferred = value;
 635   } else if (request_info.is_deferred) {
 636     request_info.is_deferred = false;
 637
 638     FollowPendingRedirect(request_id, request_info);
 639
 640     base::MessageLoop::current()->PostTask(
 641         FROM_HERE,
 642         base::Bind(&ResourceDispatcher::FlushDeferredMessages,
 643                    weak_factory_.GetWeakPtr(),
 644                    request_id));
 645   }
 646 }
 647
 648 void ResourceDispatcher::DidChangePriority(int request_id,
 649                                            net::RequestPriority new_priority,
 650                                            int intra_priority_value) {
 651   DCHECK(ContainsKey(pending_requests_, request_id));
 652   message_sender_->Send(new ResourceHostMsg_DidChangePriority(
 653       request_id, new_priority, intra_priority_value));
 654 }
 655
 656 bool ResourceDispatcher::AttachThreadedDataReceiver(
 657     int request_id, blink::WebThreadedDataReceiver* threaded_data_receiver) {
 658   PendingRequestInfo* request_info = GetPendingRequestInfo(request_id);
 659   DCHECK(request_info);
 660
 661   if (request_info->buffer != NULL) {
 662     DCHECK(!request_info->threaded_data_provider);
 663     request_info->threaded_data_provider = new ThreadedDataProvider(
 664         request_id, threaded_data_receiver, request_info->buffer,
 665         request_info->buffer_size);
 666     return true;
 667   }
 668
 669   return false;
 670 }
 671
 672 ResourceDispatcher::PendingRequestInfo::PendingRequestInfo()
 673     : peer(NULL),
 674       threaded_data_provider(NULL),
 675       resource_type(RESOURCE_TYPE_SUB_RESOURCE),
 676       is_deferred(false),
 677       download_to_file(false),
 678       blocked_response(false),
 679       buffer_size(0) {
 680 }
 681
 682 ResourceDispatcher::PendingRequestInfo::PendingRequestInfo(
 683     RequestPeer* peer,
 684     ResourceType resource_type,
 685     int origin_pid,
 686     const GURL& frame_origin,
 687     const GURL& request_url,
 688     bool download_to_file)
 689     : peer(peer),
 690       threaded_data_provider(NULL),
 691       resource_type(resource_type),
 692       origin_pid(origin_pid),
 693       is_deferred(false),
 694       url(request_url),
 695       frame_origin(frame_origin),
 696       response_url(request_url),
 697       download_to_file(download_to_file),
 698       request_start(base::TimeTicks::Now()),
 699       blocked_response(false) {}
 700
 701 ResourceDispatcher::PendingRequestInfo::~PendingRequestInfo() {
 702   if (threaded_data_provider)
 703     threaded_data_provider->Stop();
 704 }
 705
 706 void ResourceDispatcher::DispatchMessage(const IPC::Message& message) {
 707   IPC_BEGIN_MESSAGE_MAP(ResourceDispatcher, message)
 708     IPC_MESSAGE_HANDLER(ResourceMsg_UploadProgress, OnUploadProgress)
 709     IPC_MESSAGE_HANDLER(ResourceMsg_ReceivedResponse, OnReceivedResponse)
 710     IPC_MESSAGE_HANDLER(ResourceMsg_ReceivedCachedMetadata,
 711                         OnReceivedCachedMetadata)
 712     IPC_MESSAGE_HANDLER(ResourceMsg_ReceivedRedirect, OnReceivedRedirect)
 713     IPC_MESSAGE_HANDLER(ResourceMsg_SetDataBuffer, OnSetDataBuffer)
 714     IPC_MESSAGE_HANDLER(ResourceMsg_DataReceived, OnReceivedData)
 715     IPC_MESSAGE_HANDLER(ResourceMsg_DataDownloaded, OnDownloadedData)
 716     IPC_MESSAGE_HANDLER(ResourceMsg_RequestComplete, OnRequestComplete)
 717   IPC_END_MESSAGE_MAP()
 718 }
 719
 720 void ResourceDispatcher::FlushDeferredMessages(int request_id) {
 721   PendingRequestList::iterator it = pending_requests_.find(request_id);
 722   if (it == pending_requests_.end())  // The request could have become invalid.
 723     return;
 724   PendingRequestInfo& request_info = it->second;
 725   if (request_info.is_deferred)
 726     return;
 727   // Because message handlers could result in request_info being destroyed,
 728   // we need to work with a stack reference to the deferred queue.
 729   MessageQueue q;
 730   q.swap(request_info.deferred_message_queue);
 731   while (!q.empty()) {
 732     IPC::Message* m = q.front();
 733     q.pop_front();
 734     DispatchMessage(*m);
 735     delete m;
 736     // If this request is deferred in the context of the above message, then
 737     // we should honor the same and stop dispatching further messages.
 738     // We need to find the request again in the list as it may have completed
 739     // by now and the request_info instance above may be invalid.
 740     PendingRequestList::iterator index = pending_requests_.find(request_id);
 741     if (index != pending_requests_.end()) {
 742       PendingRequestInfo& pending_request = index->second;
 743       if (pending_request.is_deferred) {
 744         pending_request.deferred_message_queue.swap(q);
 745         return;
 746       }
 747     }
 748   }
 749 }
 750
 751 ResourceLoaderBridge* ResourceDispatcher::CreateBridge(
 752     const RequestInfo& request_info) {
 753   return new IPCResourceLoaderBridge(this, request_info);
 754 }
 755
 756 void ResourceDispatcher::ToResourceResponseInfo(
 757     const PendingRequestInfo& request_info,
 758     const ResourceResponseHead& browser_info,
 759     ResourceResponseInfo* renderer_info) const {
 760   *renderer_info = browser_info;
 761   if (request_info.request_start.is_null() ||
 762       request_info.response_start.is_null() ||
 763       browser_info.request_start.is_null() ||
 764       browser_info.response_start.is_null() ||
 765       browser_info.load_timing.request_start.is_null()) {
 766     return;
 767   }
 768   InterProcessTimeTicksConverter converter(
 769       LocalTimeTicks::FromTimeTicks(request_info.request_start),
 770       LocalTimeTicks::FromTimeTicks(request_info.response_start),
 771       RemoteTimeTicks::FromTimeTicks(browser_info.request_start),
 772       RemoteTimeTicks::FromTimeTicks(browser_info.response_start));
 773
 774   net::LoadTimingInfo* load_timing = &renderer_info->load_timing;
 775   RemoteToLocalTimeTicks(converter, &load_timing->request_start);
 776   RemoteToLocalTimeTicks(converter, &load_timing->proxy_resolve_start);
 777   RemoteToLocalTimeTicks(converter, &load_timing->proxy_resolve_end);
 778   RemoteToLocalTimeTicks(converter, &load_timing->connect_timing.dns_start);
 779   RemoteToLocalTimeTicks(converter, &load_timing->connect_timing.dns_end);
 780   RemoteToLocalTimeTicks(converter, &load_timing->connect_timing.connect_start);
 781   RemoteToLocalTimeTicks(converter, &load_timing->connect_timing.connect_end);
 782   RemoteToLocalTimeTicks(converter, &load_timing->connect_timing.ssl_start);
 783   RemoteToLocalTimeTicks(converter, &load_timing->connect_timing.ssl_end);
 784   RemoteToLocalTimeTicks(converter, &load_timing->send_start);
 785   RemoteToLocalTimeTicks(converter, &load_timing->send_end);
 786   RemoteToLocalTimeTicks(converter, &load_timing->receive_headers_end);
 787 }
 788
 789 base::TimeTicks ResourceDispatcher::ToRendererCompletionTime(
 790     const PendingRequestInfo& request_info,
 791     const base::TimeTicks& browser_completion_time) const {
 792   if (request_info.completion_time.is_null()) {
 793     return browser_completion_time;
 794   }
 795
 796   // TODO(simonjam): The optimal lower bound should be the most recent value of
 797   // TimeTicks::Now() returned to WebKit. Is it worth trying to cache that?
 798   // Until then, |response_start| is used as it is the most recent value
 799   // returned for this request.
 800   int64 result = std::max(browser_completion_time.ToInternalValue(),
 801                           request_info.response_start.ToInternalValue());
 802   result = std::min(result, request_info.completion_time.ToInternalValue());
 803   return base::TimeTicks::FromInternalValue(result);
 804 }
 805
 806 base::TimeTicks ResourceDispatcher::ConsumeIOTimestamp() {
 807   if (io_timestamp_ == base::TimeTicks())
 808     return base::TimeTicks::Now();
 809   base::TimeTicks result = io_timestamp_;
 810   io_timestamp_ = base::TimeTicks();
 811   return result;
 812 }
 813
 814 // static
 815 bool ResourceDispatcher::IsResourceDispatcherMessage(
 816     const IPC::Message& message) {
 817   switch (message.type()) {
 818     case ResourceMsg_UploadProgress::ID:
 819     case ResourceMsg_ReceivedResponse::ID:
 820     case ResourceMsg_ReceivedCachedMetadata::ID:
 821     case ResourceMsg_ReceivedRedirect::ID:
 822     case ResourceMsg_SetDataBuffer::ID:
 823     case ResourceMsg_DataReceived::ID:
 824     case ResourceMsg_DataDownloaded::ID:
 825     case ResourceMsg_RequestComplete::ID:
 826       return true;
 827
 828     default:
 829       break;
 830   }
 831
 832   return false;
 833 }
 834
 835 // static
 836 void ResourceDispatcher::ReleaseResourcesInDataMessage(
 837     const IPC::Message& message) {
 838   PickleIterator iter(message);
 839   int request_id;
 840   if (!message.ReadInt(&iter, &request_id)) {
 841     NOTREACHED() << "malformed resource message";
 842     return;
 843   }
 844
 845   // If the message contains a shared memory handle, we should close the handle
 846   // or there will be a memory leak.
 847   if (message.type() == ResourceMsg_SetDataBuffer::ID) {
 848     base::SharedMemoryHandle shm_handle;
 849     if (IPC::ParamTraits<base::SharedMemoryHandle>::Read(&message,
 850                                                          &iter,
 851                                                          &shm_handle)) {
 852       if (base::SharedMemory::IsHandleValid(shm_handle))
 853         base::SharedMemory::CloseHandle(shm_handle);
 854     }
 855   }
 856 }
 857
 858 // static
 859 void ResourceDispatcher::ReleaseResourcesInMessageQueue(MessageQueue* queue) {
 860   while (!queue->empty()) {
 861     IPC::Message* message = queue->front();
 862     ReleaseResourcesInDataMessage(*message);
 863     queue->pop_front();
 864     delete message;
 865   }
 866 }
 867
 868 }  // namespace content