Separates ipc code from common (http://crbug.com/16829)

chrome/common/ipc_channel_proxy.cc

-// Copyright (c) 2006-2008 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 "base/message_loop.h"
-#include "base/thread.h"
-#include "chrome/common/ipc_channel_proxy.h"
-#include "chrome/common/ipc_logging.h"
-#include "chrome/common/ipc_message_utils.h"
-
-namespace IPC {
-
-//-----------------------------------------------------------------------------
-
-ChannelProxy::Context::Context(Channel::Listener* listener,
-                               MessageFilter* filter,
-                               MessageLoop* ipc_message_loop)
-    : listener_message_loop_(MessageLoop::current()),
-      listener_(listener),
-      ipc_message_loop_(ipc_message_loop),
-      channel_(NULL),
-      peer_pid_(0),
-      channel_connected_called_(false) {
-  if (filter)
-    filters_.push_back(filter);
-}
-
-void ChannelProxy::Context::CreateChannel(const std::string& id,
-                                          const Channel::Mode& mode) {
-  DCHECK(channel_ == NULL);
-  channel_id_ = id;
-  channel_ = new Channel(id, mode, this);
-}
-
-bool ChannelProxy::Context::TryFilters(const Message& message) {
-#ifdef IPC_MESSAGE_LOG_ENABLED
-  Logging* logger = Logging::current();
-  if (logger->Enabled())
-    logger->OnPreDispatchMessage(message);
-#endif
-
-  for (size_t i = 0; i < filters_.size(); ++i) {
-    if (filters_[i]->OnMessageReceived(message)) {
-#ifdef IPC_MESSAGE_LOG_ENABLED
-      if (logger->Enabled())
-        logger->OnPostDispatchMessage(message, channel_id_);
-#endif
-      return true;
-    }
-  }
-  return false;
-}
-
-// Called on the IPC::Channel thread
-void ChannelProxy::Context::OnMessageReceived(const Message& message) {
-  // First give a chance to the filters to process this message.
-  if (!TryFilters(message))
-    OnMessageReceivedNoFilter(message);
-}
-
-// Called on the IPC::Channel thread
-void ChannelProxy::Context::OnMessageReceivedNoFilter(const Message& message) {
-  // NOTE: This code relies on the listener's message loop not going away while
-  // this thread is active.  That should be a reasonable assumption, but it
-  // feels risky.  We may want to invent some more indirect way of referring to
-  // a MessageLoop if this becomes a problem.
-  listener_message_loop_->PostTask(FROM_HERE, NewRunnableMethod(
-      this, &Context::OnDispatchMessage, message));
-}
-
-// Called on the IPC::Channel thread
-void ChannelProxy::Context::OnChannelConnected(int32 peer_pid) {
-  peer_pid_ = peer_pid;
-  for (size_t i = 0; i < filters_.size(); ++i)
-    filters_[i]->OnChannelConnected(peer_pid);
-
-  // See above comment about using listener_message_loop_ here.
-  listener_message_loop_->PostTask(FROM_HERE, NewRunnableMethod(
-      this, &Context::OnDispatchConnected));
-}
-
-// Called on the IPC::Channel thread
-void ChannelProxy::Context::OnChannelError() {
-  for (size_t i = 0; i < filters_.size(); ++i)
-    filters_[i]->OnChannelError();
-
-  // See above comment about using listener_message_loop_ here.
-  listener_message_loop_->PostTask(FROM_HERE, NewRunnableMethod(
-      this, &Context::OnDispatchError));
-}
-
-// Called on the IPC::Channel thread
-void ChannelProxy::Context::OnChannelOpened() {
-  DCHECK(channel_ != NULL);
-
-  // Assume a reference to ourselves on behalf of this thread.  This reference
-  // will be released when we are closed.
-  AddRef();
-
-  if (!channel_->Connect()) {
-    OnChannelError();
-    return;
-  }
-
-  for (size_t i = 0; i < filters_.size(); ++i)
-    filters_[i]->OnFilterAdded(channel_);
-}
-
-// Called on the IPC::Channel thread
-void ChannelProxy::Context::OnChannelClosed() {
-  // It's okay for IPC::ChannelProxy::Close to be called more than once, which
-  // would result in this branch being taken.
-  if (!channel_)
-    return;
-
-  for (size_t i = 0; i < filters_.size(); ++i) {
-    filters_[i]->OnChannelClosing();
-    filters_[i]->OnFilterRemoved();
-  }
-
-  // We don't need the filters anymore.
-  filters_.clear();
-
-  delete channel_;
-  channel_ = NULL;
-
-  // Balance with the reference taken during startup.  This may result in
-  // self-destruction.
-  Release();
-}
-
-// Called on the IPC::Channel thread
-void ChannelProxy::Context::OnSendMessage(Message* message) {
-  if (!channel_->Send(message))
-    OnChannelError();
-}
-
-// Called on the IPC::Channel thread
-void ChannelProxy::Context::OnAddFilter(MessageFilter* filter) {
-  filters_.push_back(filter);
-
-  // If the channel has already been created, then we need to send this message
-  // so that the filter gets access to the Channel.
-  if (channel_)
-    filter->OnFilterAdded(channel_);
-
-  // Balances the AddRef in ChannelProxy::AddFilter.
-  filter->Release();
-}
-
-// Called on the IPC::Channel thread
-void ChannelProxy::Context::OnRemoveFilter(MessageFilter* filter) {
-  for (size_t i = 0; i < filters_.size(); ++i) {
-    if (filters_[i].get() == filter) {
-      filter->OnFilterRemoved();
-      filters_.erase(filters_.begin() + i);
-      return;
-    }
-  }
-
-  NOTREACHED() << "filter to be removed not found";
-}
-
-// Called on the listener's thread
-void ChannelProxy::Context::OnDispatchMessage(const Message& message) {
-  if (!listener_)
-    return;
-
-  OnDispatchConnected();
-
-#ifdef IPC_MESSAGE_LOG_ENABLED
-  Logging* logger = Logging::current();
-  if (message.type() == IPC_LOGGING_ID) {
-    logger->OnReceivedLoggingMessage(message);
-    return;
-  }
-
-  if (logger->Enabled())
-    logger->OnPreDispatchMessage(message);
-#endif
-
-  listener_->OnMessageReceived(message);
-
-#ifdef IPC_MESSAGE_LOG_ENABLED
-  if (logger->Enabled())
-    logger->OnPostDispatchMessage(message, channel_id_);
-#endif
-}
-
-// Called on the listener's thread
-void ChannelProxy::Context::OnDispatchConnected() {
-  if (channel_connected_called_)
-    return;
-
-  channel_connected_called_ = true;
-  if (listener_)
-    listener_->OnChannelConnected(peer_pid_);
-}
-
-// Called on the listener's thread
-void ChannelProxy::Context::OnDispatchError() {
-  if (listener_)
-    listener_->OnChannelError();
-}
-
-//-----------------------------------------------------------------------------
-
-ChannelProxy::ChannelProxy(const std::string& channel_id, Channel::Mode mode,
-                           Channel::Listener* listener, MessageFilter* filter,
-                           MessageLoop* ipc_thread)
-    : context_(new Context(listener, filter, ipc_thread)) {
-  Init(channel_id, mode, ipc_thread, true);
-}
-
-ChannelProxy::ChannelProxy(const std::string& channel_id, Channel::Mode mode,
-                           MessageLoop* ipc_thread, Context* context,
-                           bool create_pipe_now)
-    : context_(context) {
-  Init(channel_id, mode, ipc_thread, create_pipe_now);
-}
-
-void ChannelProxy::Init(const std::string& channel_id, Channel::Mode mode,
-                        MessageLoop* ipc_thread_loop, bool create_pipe_now) {
-  if (create_pipe_now) {
-    // Create the channel immediately.  This effectively sets up the
-    // low-level pipe so that the client can connect.  Without creating
-    // the pipe immediately, it is possible for a listener to attempt
-    // to connect and get an error since the pipe doesn't exist yet.
-    context_->CreateChannel(channel_id, mode);
-  } else {
-    context_->ipc_message_loop()->PostTask(FROM_HERE, NewRunnableMethod(
-        context_.get(), &Context::CreateChannel, channel_id, mode));
-  }
-
-  // complete initialization on the background thread
-  context_->ipc_message_loop()->PostTask(FROM_HERE, NewRunnableMethod(
-      context_.get(), &Context::OnChannelOpened));
-}
-
-void ChannelProxy::Close() {
-  // Clear the backpointer to the listener so that any pending calls to
-  // Context::OnDispatchMessage or OnDispatchError will be ignored.  It is
-  // possible that the channel could be closed while it is receiving messages!
-  context_->Clear();
-
-  if (context_->ipc_message_loop()) {
-    context_->ipc_message_loop()->PostTask(FROM_HERE, NewRunnableMethod(
-        context_.get(), &Context::OnChannelClosed));
-  }
-}
-
-bool ChannelProxy::Send(Message* message) {
-#ifdef IPC_MESSAGE_LOG_ENABLED
-  Logging::current()->OnSendMessage(message, context_->channel_id());
-#endif
-
-  context_->ipc_message_loop()->PostTask(FROM_HERE, NewRunnableMethod(
-      context_.get(), &Context::OnSendMessage, message));
-  return true;
-}
-
-void ChannelProxy::AddFilter(MessageFilter* filter) {
-  // We want to addref the filter to prevent it from
-  // being destroyed before the OnAddFilter call is invoked.
-  filter->AddRef();
-  context_->ipc_message_loop()->PostTask(FROM_HERE, NewRunnableMethod(
-      context_.get(), &Context::OnAddFilter, filter));
-}
-
-void ChannelProxy::RemoveFilter(MessageFilter* filter) {
-  context_->ipc_message_loop()->PostTask(FROM_HERE, NewRunnableMethod(
-      context_.get(), &Context::OnRemoveFilter, filter));
-}
-
-#if defined(OS_POSIX)
-// See the TODO regarding lazy initialization of the channel in
-// ChannelProxy::Init().
-// We assume that IPC::Channel::GetClientFileDescriptorMapping() is thread-safe.
-int ChannelProxy::GetClientFileDescriptor() const {
-  Channel *channel = context_.get()->channel_;
-  DCHECK(channel); // Channel must have been created first.
-  return channel->GetClientFileDescriptor();
-}
-#endif
-
-//-----------------------------------------------------------------------------
-
-}  // namespace IPC