blob: 5c4d743cb3c9b0274cd23c86037c546a0e3c0009 [file] [log] [blame]
// 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 "ipc/ipc_channel_proxy.h"
#include "base/bind.h"
#include "base/compiler_specific.h"
#include "base/location.h"
#include "base/memory/ref_counted.h"
#include "base/memory/scoped_ptr.h"
#include "base/single_thread_task_runner.h"
#include "base/thread_task_runner_handle.h"
#include "ipc/ipc_listener.h"
#include "ipc/ipc_logging.h"
#include "ipc/ipc_message_macros.h"
#include "ipc/message_filter.h"
#include "ipc/message_filter_router.h"
namespace IPC {
//------------------------------------------------------------------------------
ChannelProxy::Context::Context(Listener* listener,
base::SingleThreadTaskRunner* ipc_task_runner)
: listener_task_runner_(base::ThreadTaskRunnerHandle::Get()),
listener_(listener),
ipc_task_runner_(ipc_task_runner),
channel_connected_called_(false),
message_filter_router_(new MessageFilterRouter()),
peer_pid_(base::kNullProcessId) {
DCHECK(ipc_task_runner_.get());
// The Listener thread where Messages are handled must be a separate thread
// to avoid oversubscribing the IO thread. If you trigger this error, you
// need to either:
// 1) Create the ChannelProxy on a different thread, or
// 2) Just use Channel
// Note, we currently make an exception for a NULL listener. That usage
// basically works, but is outside the intent of ChannelProxy. This support
// will disappear, so please don't rely on it. See crbug.com/364241
DCHECK(!listener || (ipc_task_runner_.get() != listener_task_runner_.get()));
}
ChannelProxy::Context::~Context() {
}
void ChannelProxy::Context::ClearIPCTaskRunner() {
ipc_task_runner_ = NULL;
}
void ChannelProxy::Context::CreateChannel(const IPC::ChannelHandle& handle,
const Channel::Mode& mode) {
DCHECK(!channel_);
channel_id_ = handle.name;
channel_.reset(new Channel(handle, mode, this));
}
bool ChannelProxy::Context::TryFilters(const Message& message) {
DCHECK(message_filter_router_);
#ifdef IPC_MESSAGE_LOG_ENABLED
Logging* logger = Logging::GetInstance();
if (logger->Enabled())
logger->OnPreDispatchMessage(message);
#endif
if (message_filter_router_->TryFilters(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
bool ChannelProxy::Context::OnMessageReceived(const Message& message) {
// First give a chance to the filters to process this message.
if (!TryFilters(message))
OnMessageReceivedNoFilter(message);
return true;
}
// Called on the IPC::Channel thread
bool ChannelProxy::Context::OnMessageReceivedNoFilter(const Message& message) {
listener_task_runner_->PostTask(
FROM_HERE, base::Bind(&Context::OnDispatchMessage, this, message));
return true;
}
// Called on the IPC::Channel thread
void ChannelProxy::Context::OnChannelConnected(int32 peer_pid) {
// We cache off the peer_pid so it can be safely accessed from both threads.
peer_pid_ = channel_->peer_pid();
// Add any pending filters. This avoids a race condition where someone
// creates a ChannelProxy, calls AddFilter, and then right after starts the
// peer process. The IO thread could receive a message before the task to add
// the filter is run on the IO thread.
OnAddFilter();
// See above comment about using listener_task_runner_ here.
listener_task_runner_->PostTask(
FROM_HERE, base::Bind(&Context::OnDispatchConnected, this));
}
// 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_task_runner_ here.
listener_task_runner_->PostTask(
FROM_HERE, base::Bind(&Context::OnDispatchError, this));
}
// 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_.get());
}
// 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.
message_filter_router_->Clear();
filters_.clear();
// We don't need the lock, because at this point, the listener thread can't
// access it any more.
pending_filters_.clear();
channel_.reset();
// Balance with the reference taken during startup. This may result in
// self-destruction.
Release();
}
void ChannelProxy::Context::Clear() {
listener_ = NULL;
}
// Called on the IPC::Channel thread
void ChannelProxy::Context::OnSendMessage(scoped_ptr<Message> message) {
if (!channel_) {
OnChannelClosed();
return;
}
if (!channel_->Send(message.release()))
OnChannelError();
}
// Called on the IPC::Channel thread
void ChannelProxy::Context::OnAddFilter() {
// Our OnChannelConnected method has not yet been called, so we can't be
// sure that channel_ is valid yet. When OnChannelConnected *is* called,
// it invokes OnAddFilter, so any pending filter(s) will be added at that
// time.
if (peer_pid_ == base::kNullProcessId)
return;
std::vector<scoped_refptr<MessageFilter> > new_filters;
{
base::AutoLock auto_lock(pending_filters_lock_);
new_filters.swap(pending_filters_);
}
for (size_t i = 0; i < new_filters.size(); ++i) {
filters_.push_back(new_filters[i]);
message_filter_router_->AddFilter(new_filters[i].get());
// The channel has already been created and connected, so we need to
// inform the filters right now.
new_filters[i]->OnFilterAdded(channel_.get());
new_filters[i]->OnChannelConnected(peer_pid_);
}
}
// Called on the IPC::Channel thread
void ChannelProxy::Context::OnRemoveFilter(MessageFilter* filter) {
if (peer_pid_ == base::kNullProcessId) {
// The channel is not yet connected, so any filters are still pending.
base::AutoLock auto_lock(pending_filters_lock_);
for (size_t i = 0; i < pending_filters_.size(); ++i) {
if (pending_filters_[i].get() == filter) {
filter->OnFilterRemoved();
pending_filters_.erase(pending_filters_.begin() + i);
return;
}
}
return;
}
if (!channel_)
return; // The filters have already been deleted.
message_filter_router_->RemoveFilter(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::AddFilter(MessageFilter* filter) {
base::AutoLock auto_lock(pending_filters_lock_);
pending_filters_.push_back(make_scoped_refptr(filter));
ipc_task_runner_->PostTask(
FROM_HERE, base::Bind(&Context::OnAddFilter, this));
}
// Called on the listener's thread
void ChannelProxy::Context::OnDispatchMessage(const Message& message) {
#ifdef IPC_MESSAGE_LOG_ENABLED
Logging* logger = Logging::GetInstance();
std::string name;
logger->GetMessageText(message.type(), &name, &message, NULL);
TRACE_EVENT1("ipc", "ChannelProxy::Context::OnDispatchMessage",
"name", name);
#else
TRACE_EVENT2("ipc", "ChannelProxy::Context::OnDispatchMessage",
"class", IPC_MESSAGE_ID_CLASS(message.type()),
"line", IPC_MESSAGE_ID_LINE(message.type()));
#endif
if (!listener_)
return;
OnDispatchConnected();
#ifdef IPC_MESSAGE_LOG_ENABLED
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 IPC::ChannelHandle& channel_handle,
Channel::Mode mode,
Listener* listener,
base::SingleThreadTaskRunner* ipc_task_runner)
: context_(new Context(listener, ipc_task_runner)),
did_init_(false) {
Init(channel_handle, mode, true);
}
ChannelProxy::ChannelProxy(Context* context)
: context_(context),
did_init_(false) {
}
ChannelProxy::~ChannelProxy() {
DCHECK(CalledOnValidThread());
Close();
}
void ChannelProxy::Init(const IPC::ChannelHandle& channel_handle,
Channel::Mode mode,
bool create_pipe_now) {
DCHECK(CalledOnValidThread());
DCHECK(!did_init_);
#if defined(OS_POSIX)
// When we are creating a server on POSIX, we need its file descriptor
// to be created immediately so that it can be accessed and passed
// to other processes. Forcing it to be created immediately avoids
// race conditions that may otherwise arise.
if (mode & Channel::MODE_SERVER_FLAG) {
create_pipe_now = true;
}
#endif // defined(OS_POSIX)
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_handle, mode);
} else {
context_->ipc_task_runner()->PostTask(
FROM_HERE, base::Bind(&Context::CreateChannel, context_.get(),
channel_handle, mode));
}
// complete initialization on the background thread
context_->ipc_task_runner()->PostTask(
FROM_HERE, base::Bind(&Context::OnChannelOpened, context_.get()));
did_init_ = true;
}
void ChannelProxy::Close() {
DCHECK(CalledOnValidThread());
// 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_task_runner()) {
context_->ipc_task_runner()->PostTask(
FROM_HERE, base::Bind(&Context::OnChannelClosed, context_.get()));
}
}
bool ChannelProxy::Send(Message* message) {
DCHECK(did_init_);
// TODO(alexeypa): add DCHECK(CalledOnValidThread()) here. Currently there are
// tests that call Send() from a wrong thread. See http://crbug.com/163523.
#ifdef IPC_MESSAGE_LOG_ENABLED
Logging::GetInstance()->OnSendMessage(message, context_->channel_id());
#endif
context_->ipc_task_runner()->PostTask(
FROM_HERE,
base::Bind(&ChannelProxy::Context::OnSendMessage,
context_, base::Passed(scoped_ptr<Message>(message))));
return true;
}
void ChannelProxy::AddFilter(MessageFilter* filter) {
DCHECK(CalledOnValidThread());
context_->AddFilter(filter);
}
void ChannelProxy::RemoveFilter(MessageFilter* filter) {
DCHECK(CalledOnValidThread());
context_->ipc_task_runner()->PostTask(
FROM_HERE, base::Bind(&Context::OnRemoveFilter, context_.get(),
make_scoped_refptr(filter)));
}
void ChannelProxy::ClearIPCTaskRunner() {
DCHECK(CalledOnValidThread());
context()->ClearIPCTaskRunner();
}
#if defined(OS_POSIX) && !defined(OS_NACL)
// See the TODO regarding lazy initialization of the channel in
// ChannelProxy::Init().
int ChannelProxy::GetClientFileDescriptor() {
DCHECK(CalledOnValidThread());
Channel* channel = context_.get()->channel_.get();
// Channel must have been created first.
DCHECK(channel) << context_.get()->channel_id_;
return channel->GetClientFileDescriptor();
}
int ChannelProxy::TakeClientFileDescriptor() {
DCHECK(CalledOnValidThread());
Channel* channel = context_.get()->channel_.get();
// Channel must have been created first.
DCHECK(channel) << context_.get()->channel_id_;
return channel->TakeClientFileDescriptor();
}
bool ChannelProxy::GetPeerEuid(uid_t* peer_euid) const {
DCHECK(CalledOnValidThread());
Channel* channel = context_.get()->channel_.get();
// Channel must have been created first.
DCHECK(channel) << context_.get()->channel_id_;
return channel->GetPeerEuid(peer_euid);
}
#endif
//-----------------------------------------------------------------------------
} // namespace IPC