Revert 183382

content/browser/loader/resource_scheduler.cc

Index: content/browser/loader/resource_scheduler.cc
===================================================================
--- content/browser/loader/resource_scheduler.cc	(revision 183842)
+++ content/browser/loader/resource_scheduler.cc	(working copy)
@@ -1,242 +0,0 @@
-// Copyright (c) 2012 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#include "content/browser/loader/resource_scheduler.h"
-
-#include "base/stl_util.h"
-#include "content/common/resource_messages.h"
-#include "content/browser/loader/resource_message_delegate.h"
-#include "content/public/browser/resource_controller.h"
-#include "content/public/browser/resource_throttle.h"
-#include "ipc/ipc_message_macros.h"
-#include "net/base/load_flags.h"
-#include "net/base/request_priority.h"
-#include "net/url_request/url_request.h"
-
-namespace content {
-
-// TODO(simonjam): This is arbitrary. Experiment.
-static const int kMaxNumNavigationsToTrack = 5;
-
-class ResourceScheduler::ScheduledResourceRequest
-    : public ResourceMessageDelegate,
-      public ResourceThrottle {
- public:
-  ScheduledResourceRequest(const ClientId& client_id,
-                           net::URLRequest* request,
-                           ResourceScheduler* scheduler)
-      : ResourceMessageDelegate(request),
-        client_id_(client_id),
-        request_(request),
-        ready_(false),
-        deferred_(false),
-        scheduler_(scheduler) {
-  }
-
-  virtual ~ScheduledResourceRequest() {
-    scheduler_->RemoveRequest(this);
-  }
-
-  void Start() {
-    ready_ = true;
-    if (deferred_ && request_->status().is_success()) {
-      deferred_ = false;
-      controller()->Resume();
-    }
-  }
-
-  const ClientId& client_id() const { return client_id_; }
-  const net::URLRequest& url_request() const { return *request_; }
-
- private:
-  // ResourceMessageDelegate interface:
-  virtual bool OnMessageReceived(const IPC::Message& message,
-                                 bool* message_was_ok) OVERRIDE {
-    bool handled = true;
-    IPC_BEGIN_MESSAGE_MAP_EX(ScheduledResourceRequest, message, *message_was_ok)
-      IPC_MESSAGE_HANDLER(ResourceHostMsg_DidChangePriority, DidChangePriority)
-      IPC_MESSAGE_UNHANDLED(handled = false)
-    IPC_END_MESSAGE_MAP_EX()
-    return handled;
-  }
-
-  // ResourceThrottle interface:
-  virtual void WillStartRequest(bool* defer) OVERRIDE {
-    deferred_ = *defer = !ready_;
-  }
-
-  void DidChangePriority(int request_id, net::RequestPriority new_priority) {
-    net::RequestPriority old_priority = request_->priority();
-    request_->set_priority(new_priority);
-    if (new_priority > old_priority) {
-      Start();
-    }
-  }
-
-  ClientId client_id_;
-  net::URLRequest* request_;
-  bool ready_;
-  bool deferred_;
-  ResourceScheduler* scheduler_;
-
-  DISALLOW_COPY_AND_ASSIGN(ScheduledResourceRequest);
-};
-
-ResourceScheduler::ResourceScheduler()
-    : client_map_(kMaxNumNavigationsToTrack) {
-}
-
-ResourceScheduler::~ResourceScheduler() {
-  for (ClientMap::iterator it ALLOW_UNUSED = client_map_.begin();
-       it != client_map_.end(); ++it) {
-    DCHECK(it->second->pending_requests.empty());
-    DCHECK(it->second->in_flight_requests.empty());
-  }
-  DCHECK(unowned_requests_.empty());
-}
-
-scoped_ptr<ResourceThrottle> ResourceScheduler::ScheduleRequest(
-    int child_id,
-    int route_id,
-    net::URLRequest* url_request) {
-  DCHECK(CalledOnValidThread());
-  ClientId client_id = MakeClientId(child_id, route_id);
-  scoped_ptr<ScheduledResourceRequest> request(
-      new ScheduledResourceRequest(client_id, url_request, this));
-
-  ClientMap::iterator it = client_map_.Get(client_id);
-  if (it == client_map_.end()) {
-    // There are several ways this could happen:
-    // 1. <a ping> requests don't have a route_id.
-    // 2. Most unittests don't send the IPCs needed to register Clients.
-    // 3. The tab is closed while a RequestResource IPC is in flight.
-    // 4. The tab hasn't navigated recently.
-    unowned_requests_.insert(request.get());
-    request->Start();
-    return request.PassAs<ResourceThrottle>();
-  }
-
-  Client* client = it->second;
-
-  bool is_synchronous = (url_request->load_flags() & net::LOAD_IGNORE_LIMITS) ==
-      net::LOAD_IGNORE_LIMITS;
-  bool is_low_priority =
-      url_request->priority() < net::MEDIUM && !is_synchronous;
-
-  if (is_low_priority && !client->in_flight_requests.empty() &&
-      !client->has_body) {
-    client->pending_requests.push_back(request.get());
-  } else {
-    StartRequest(request.get(), client);
-  }
-  return request.PassAs<ResourceThrottle>();
-}
-
-void ResourceScheduler::RemoveRequest(ScheduledResourceRequest* request) {
-  DCHECK(CalledOnValidThread());
-  if (ContainsKey(unowned_requests_, request)) {
-    unowned_requests_.erase(request);
-    return;
-  }
-
-  ClientMap::iterator client_it = client_map_.Get(request->client_id());
-  if (client_it == client_map_.end()) {
-    return;
-  }
-
-  Client* client = client_it->second;
-  RequestSet::iterator request_it = client->in_flight_requests.find(request);
-  if (request_it == client->in_flight_requests.end()) {
-    bool removed = false;
-    RequestQueue::iterator queue_it;
-    for (queue_it = client->pending_requests.begin();
-         queue_it != client->pending_requests.end(); ++queue_it) {
-      if (*queue_it == request) {
-        client->pending_requests.erase(queue_it);
-        removed = true;
-        break;
-      }
-    }
-    DCHECK(removed);
-    DCHECK(!ContainsKey(client->in_flight_requests, request));
-  } else {
-    size_t erased = client->in_flight_requests.erase(request);
-    DCHECK(erased);
-  }
-
-  if (client->in_flight_requests.empty()) {
-    // Since the network is now idle, we may as well load some of the low
-    // priority requests.
-    LoadPendingRequests(client);
-  }
-}
-
-void ResourceScheduler::OnNavigate(int child_id, int route_id) {
-  DCHECK(CalledOnValidThread());
-  ClientId client_id = MakeClientId(child_id, route_id);
-
-  ClientMap::iterator it = client_map_.Get(client_id);
-  if (it == client_map_.end()) {
-    it = client_map_.Put(client_id, new Client(this));
-  }
-
-  Client* client = it->second;
-  client->has_body = false;
-}
-
-void ResourceScheduler::OnWillInsertBody(int child_id, int route_id) {
-  DCHECK(CalledOnValidThread());
-  ClientId client_id = MakeClientId(child_id, route_id);
-  ClientMap::iterator it = client_map_.Get(client_id);
-  if (it == client_map_.end()) {
-    return;
-  }
-
-  Client* client = it->second;
-  if (!client->has_body) {
-    client->has_body = true;
-    LoadPendingRequests(client);
-  }
-}
-
-void ResourceScheduler::StartRequest(ScheduledResourceRequest* request,
-                                     Client* client) {
-  client->in_flight_requests.insert(request);
-  request->Start();
-}
-
-void ResourceScheduler::LoadPendingRequests(Client* client) {
-  while (!client->pending_requests.empty()) {
-    ScheduledResourceRequest* request = client->pending_requests.front();
-    client->pending_requests.erase(client->pending_requests.begin());
-    StartRequest(request, client);
-  }
-}
-
-void ResourceScheduler::RemoveClient(Client* client) {
-  LoadPendingRequests(client);
-  for (RequestSet::iterator it = client->in_flight_requests.begin();
-       it != client->in_flight_requests.end(); ++it) {
-    unowned_requests_.insert(*it);
-  }
-  client->in_flight_requests.clear();
-}
-
-ResourceScheduler::ClientId ResourceScheduler::MakeClientId(
-    int child_id, int route_id) {
-  return (static_cast<ResourceScheduler::ClientId>(child_id) << 32) | route_id;
-}
-
-ResourceScheduler::Client::Client(ResourceScheduler* scheduler)
-    : has_body(false),
-      scheduler_(scheduler) {
-}
-
-ResourceScheduler::Client::~Client() {
-  scheduler_->RemoveClient(this);
-  DCHECK(in_flight_requests.empty());
-  DCHECK(pending_requests.empty());
-}
-
-}  // namespace content