content/child/webmessageportchannel_impl.cc

   1 // Copyright (c) 2011 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/webmessageportchannel_impl.h"
   6
   7 #include "base/bind.h"
   8 #include "base/message_loop/message_loop_proxy.h"
   9 #include "content/child/child_process.h"
  10 #include "content/child/child_thread.h"
  11 #include "content/common/message_port_messages.h"
  12 #include "third_party/WebKit/public/platform/WebMessagePortChannelClient.h"
  13 #include "third_party/WebKit/public/platform/WebString.h"
  14
  15 using blink::WebMessagePortChannel;
  16 using blink::WebMessagePortChannelArray;
  17 using blink::WebMessagePortChannelClient;
  18 using blink::WebString;
  19
  20 namespace content {
  21
  22 WebMessagePortChannelImpl::WebMessagePortChannelImpl(
  23     base::MessageLoopProxy* child_thread_loop)
  24     : client_(NULL),
  25       route_id_(MSG_ROUTING_NONE),
  26       message_port_id_(MSG_ROUTING_NONE),
  27       child_thread_loop_(child_thread_loop) {
  28   AddRef();
  29   Init();
  30 }
  31
  32 WebMessagePortChannelImpl::WebMessagePortChannelImpl(
  33     int route_id,
  34     int message_port_id,
  35     base::MessageLoopProxy* child_thread_loop)
  36     : client_(NULL),
  37       route_id_(route_id),
  38       message_port_id_(message_port_id),
  39       child_thread_loop_(child_thread_loop) {
  40   AddRef();
  41   Init();
  42 }
  43
  44 WebMessagePortChannelImpl::~WebMessagePortChannelImpl() {
  45   // If we have any queued messages with attached ports, manually destroy them.
  46   while (!message_queue_.empty()) {
  47     const std::vector<WebMessagePortChannelImpl*>& channel_array =
  48         message_queue_.front().ports;
  49     for (size_t i = 0; i < channel_array.size(); i++) {
  50       channel_array[i]->destroy();
  51     }
  52     message_queue_.pop();
  53   }
  54
  55   if (message_port_id_ != MSG_ROUTING_NONE)
  56     Send(new MessagePortHostMsg_DestroyMessagePort(message_port_id_));
  57
  58   if (route_id_ != MSG_ROUTING_NONE)
  59     ChildThread::current()->GetRouter()->RemoveRoute(route_id_);
  60 }
  61
  62 // static
  63 void WebMessagePortChannelImpl::CreatePair(
  64     base::MessageLoopProxy* child_thread_loop,
  65     blink::WebMessagePortChannel** channel1,
  66     blink::WebMessagePortChannel** channel2) {
  67   WebMessagePortChannelImpl* impl1 =
  68       new WebMessagePortChannelImpl(child_thread_loop);
  69   WebMessagePortChannelImpl* impl2 =
  70       new WebMessagePortChannelImpl(child_thread_loop);
  71
  72   impl1->Entangle(impl2);
  73   impl2->Entangle(impl1);
  74
  75   *channel1 = impl1;
  76   *channel2 = impl2;
  77 }
  78
  79 // static
  80 std::vector<int> WebMessagePortChannelImpl::ExtractMessagePortIDs(
  81     WebMessagePortChannelArray* channels) {
  82   std::vector<int> message_port_ids;
  83   if (channels) {
  84     message_port_ids.resize(channels->size());
  85     // Extract the port IDs from the source array, then free it.
  86     for (size_t i = 0; i < channels->size(); ++i) {
  87       WebMessagePortChannelImpl* webchannel =
  88           static_cast<WebMessagePortChannelImpl*>((*channels)[i]);
  89       // The message port ids might not be set up yet if this channel
  90       // wasn't created on the main thread.
  91       DCHECK(webchannel->child_thread_loop_->BelongsToCurrentThread());
  92       message_port_ids[i] = webchannel->message_port_id();
  93       webchannel->QueueMessages();
  94       DCHECK(message_port_ids[i] != MSG_ROUTING_NONE);
  95     }
  96     delete channels;
  97   }
  98   return message_port_ids;
  99 }
 100
 101 void WebMessagePortChannelImpl::setClient(WebMessagePortChannelClient* client) {
 102   // Must lock here since client_ is called on the main thread.
 103   base::AutoLock auto_lock(lock_);
 104   client_ = client;
 105 }
 106
 107 void WebMessagePortChannelImpl::destroy() {
 108   setClient(NULL);
 109
 110   // Release the object on the main thread, since the destructor might want to
 111   // send an IPC, and that has to happen on the main thread.
 112   child_thread_loop_->ReleaseSoon(FROM_HERE, this);
 113 }
 114
 115 void WebMessagePortChannelImpl::postMessage(
 116     const WebString& message,
 117     WebMessagePortChannelArray* channels) {
 118   if (!child_thread_loop_->BelongsToCurrentThread()) {
 119     child_thread_loop_->PostTask(
 120         FROM_HERE,
 121         base::Bind(
 122             &WebMessagePortChannelImpl::PostMessage, this,
 123             static_cast<base::string16>(message), channels));
 124   } else {
 125     PostMessage(message, channels);
 126   }
 127 }
 128
 129 void WebMessagePortChannelImpl::PostMessage(
 130     const base::string16& message,
 131     WebMessagePortChannelArray* channels) {
 132   IPC::Message* msg = new MessagePortHostMsg_PostMessage(
 133       message_port_id_, message, ExtractMessagePortIDs(channels));
 134   Send(msg);
 135 }
 136
 137 bool WebMessagePortChannelImpl::tryGetMessage(
 138     WebString* message,
 139     WebMessagePortChannelArray& channels) {
 140   base::AutoLock auto_lock(lock_);
 141   if (message_queue_.empty())
 142     return false;
 143
 144   *message = message_queue_.front().message;
 145   const std::vector<WebMessagePortChannelImpl*>& channel_array =
 146       message_queue_.front().ports;
 147   WebMessagePortChannelArray result_ports(channel_array.size());
 148   for (size_t i = 0; i < channel_array.size(); i++) {
 149     result_ports[i] = channel_array[i];
 150   }
 151
 152   channels.swap(result_ports);
 153   message_queue_.pop();
 154   return true;
 155 }
 156
 157 void WebMessagePortChannelImpl::Init() {
 158   if (!child_thread_loop_->BelongsToCurrentThread()) {
 159     child_thread_loop_->PostTask(
 160         FROM_HERE, base::Bind(&WebMessagePortChannelImpl::Init, this));
 161     return;
 162   }
 163
 164   if (route_id_ == MSG_ROUTING_NONE) {
 165     DCHECK(message_port_id_ == MSG_ROUTING_NONE);
 166     Send(new MessagePortHostMsg_CreateMessagePort(
 167         &route_id_, &message_port_id_));
 168   }
 169
 170   ChildThread::current()->GetRouter()->AddRoute(route_id_, this);
 171 }
 172
 173 void WebMessagePortChannelImpl::Entangle(
 174     scoped_refptr<WebMessagePortChannelImpl> channel) {
 175   // The message port ids might not be set up yet, if this channel wasn't
 176   // created on the main thread.  So need to wait until we're on the main thread
 177   // before getting the other message port id.
 178   if (!child_thread_loop_->BelongsToCurrentThread()) {
 179     child_thread_loop_->PostTask(
 180         FROM_HERE,
 181         base::Bind(&WebMessagePortChannelImpl::Entangle, this, channel));
 182     return;
 183   }
 184
 185   Send(new MessagePortHostMsg_Entangle(
 186       message_port_id_, channel->message_port_id()));
 187 }
 188
 189 void WebMessagePortChannelImpl::QueueMessages() {
 190   if (!child_thread_loop_->BelongsToCurrentThread()) {
 191     child_thread_loop_->PostTask(
 192         FROM_HERE, base::Bind(&WebMessagePortChannelImpl::QueueMessages, this));
 193     return;
 194   }
 195   // This message port is being sent elsewhere (perhaps to another process).
 196   // The new endpoint needs to receive the queued messages, including ones that
 197   // could still be in-flight.  So we tell the browser to queue messages, and it
 198   // sends us an ack, whose receipt we know means that no more messages are
 199   // in-flight.  We then send the queued messages to the browser, which prepends
 200   // them to the ones it queued and it sends them to the new endpoint.
 201   Send(new MessagePortHostMsg_QueueMessages(message_port_id_));
 202
 203   // The process could potentially go away while we're still waiting for
 204   // in-flight messages.  Ensure it stays alive.
 205   ChildProcess::current()->AddRefProcess();
 206 }
 207
 208 void WebMessagePortChannelImpl::Send(IPC::Message* message) {
 209   if (!child_thread_loop_->BelongsToCurrentThread()) {
 210     DCHECK(!message->is_sync());
 211     child_thread_loop_->PostTask(
 212         FROM_HERE,
 213         base::Bind(&WebMessagePortChannelImpl::Send, this, message));
 214     return;
 215   }
 216
 217   ChildThread::current()->GetRouter()->Send(message);
 218 }
 219
 220 bool WebMessagePortChannelImpl::OnMessageReceived(const IPC::Message& message) {
 221   bool handled = true;
 222   IPC_BEGIN_MESSAGE_MAP(WebMessagePortChannelImpl, message)
 223     IPC_MESSAGE_HANDLER(MessagePortMsg_Message, OnMessage)
 224     IPC_MESSAGE_HANDLER(MessagePortMsg_MessagesQueued, OnMessagesQueued)
 225     IPC_MESSAGE_UNHANDLED(handled = false)
 226   IPC_END_MESSAGE_MAP()
 227   return handled;
 228 }
 229
 230 void WebMessagePortChannelImpl::OnMessage(
 231     const base::string16& message,
 232     const std::vector<int>& sent_message_port_ids,
 233     const std::vector<int>& new_routing_ids) {
 234   base::AutoLock auto_lock(lock_);
 235   Message msg;
 236   msg.message = message;
 237   if (!sent_message_port_ids.empty()) {
 238     msg.ports.resize(sent_message_port_ids.size());
 239     for (size_t i = 0; i < sent_message_port_ids.size(); ++i) {
 240       msg.ports[i] = new WebMessagePortChannelImpl(new_routing_ids[i],
 241                                                    sent_message_port_ids[i],
 242                                                    child_thread_loop_.get());
 243     }
 244   }
 245
 246   bool was_empty = message_queue_.empty();
 247   message_queue_.push(msg);
 248   if (client_ && was_empty)
 249     client_->messageAvailable();
 250 }
 251
 252 void WebMessagePortChannelImpl::OnMessagesQueued() {
 253   std::vector<QueuedMessage> queued_messages;
 254
 255   {
 256     base::AutoLock auto_lock(lock_);
 257     queued_messages.reserve(message_queue_.size());
 258     while (!message_queue_.empty()) {
 259       base::string16 message = message_queue_.front().message;
 260       const std::vector<WebMessagePortChannelImpl*>& channel_array =
 261           message_queue_.front().ports;
 262       std::vector<int> port_ids(channel_array.size());
 263       for (size_t i = 0; i < channel_array.size(); ++i) {
 264         port_ids[i] = channel_array[i]->message_port_id();
 265         channel_array[i]->QueueMessages();
 266       }
 267       queued_messages.push_back(std::make_pair(message, port_ids));
 268       message_queue_.pop();
 269     }
 270   }
 271
 272   Send(new MessagePortHostMsg_SendQueuedMessages(
 273       message_port_id_, queued_messages));
 274
 275   message_port_id_ = MSG_ROUTING_NONE;
 276
 277   Release();
 278   ChildProcess::current()->ReleaseProcess();
 279 }
 280
 281 WebMessagePortChannelImpl::Message::Message() {}
 282
 283 WebMessagePortChannelImpl::Message::~Message() {}
 284
 285 }  // namespace content