blob: 1966e5846e74b0661d4e2a3fa37907d5268aaa99 [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 "base/memory/ref_counted.h"
#include "base/process/process.h"
#include "content/common/content_export.h"
#include "content/public/browser/browser_thread.h"
#include "ipc/ipc_channel_proxy.h"
#if defined(OS_WIN)
#include "base/synchronization/lock.h"
namespace base {
class TaskRunner;
namespace IPC {
class MessageFilter;
namespace content {
struct BrowserMessageFilterTraits;
// Base class for message filters in the browser process. You can receive and
// send messages on any thread.
class CONTENT_EXPORT BrowserMessageFilter
: public base::RefCountedThreadSafe<
BrowserMessageFilter, BrowserMessageFilterTraits>,
public IPC::Sender {
explicit BrowserMessageFilter(uint32 message_class_to_filter);
BrowserMessageFilter(const uint32* message_classes_to_filter,
size_t num_message_classes_to_filter);
// These match the corresponding IPC::MessageFilter methods and are always
// called on the IO thread.
virtual void OnFilterAdded(IPC::Sender* sender) {}
virtual void OnFilterRemoved() {}
virtual void OnChannelClosing() {}
virtual void OnChannelConnected(int32 peer_pid) {}
// Called when the message filter is about to be deleted. This gives
// derived classes the option of controlling which thread they're deleted
// on etc.
virtual void OnDestruct() const;
// IPC::Sender implementation. Can be called on any thread. Can't send sync
// messages (since we don't want to block the browser on any other process).
bool Send(IPC::Message* message) override;
// If you want the given message to be dispatched to your OnMessageReceived on
// a different thread, there are two options, either
// OverrideThreadForMessage or OverrideTaskRunnerForMessage.
// If neither is overriden, the message will be dispatched on the IO thread.
// If you want the message to be dispatched on a particular well-known
// browser thread, change |thread| to the id of the target thread
virtual void OverrideThreadForMessage(
const IPC::Message& message,
BrowserThread::ID* thread) {}
// If you want the message to be dispatched via the SequencedWorkerPool,
// return a non-null task runner which will target tasks accordingly.
// Note: To target the UI thread, please use OverrideThreadForMessage
// since that has extra checks to avoid deadlocks.
virtual base::TaskRunner* OverrideTaskRunnerForMessage(
const IPC::Message& message);
// Override this to receive messages.
// Your function will normally be called on the IO thread. However, if your
// OverrideXForMessage modifies the thread used to dispatch the message,
// your function will be called on the requested thread.
virtual bool OnMessageReceived(const IPC::Message& message) = 0;
// Can be called on any thread, after OnChannelConnected is called.
base::ProcessHandle PeerHandle();
// Can be called on any thread, after OnChannelConnected is called.
base::ProcessId peer_pid() const { return peer_process_.Pid(); }
void set_peer_process_for_testing(base::Process peer_process) {
peer_process_ = peer_process.Pass();
// Checks that the given message can be dispatched on the UI thread, depending
// on the platform. If not, returns false and an error ot the sender.
static bool CheckCanDispatchOnUI(const IPC::Message& message,
IPC::Sender* sender);
// Call this if a message couldn't be deserialized. This kills the renderer.
// Can be called on any thread.
virtual void BadMessageReceived();
const std::vector<uint32>& message_classes_to_filter() const {
return message_classes_to_filter_;
~BrowserMessageFilter() override;
friend class base::RefCountedThreadSafe<BrowserMessageFilter,
class Internal;
friend class BrowserChildProcessHostImpl;
friend class BrowserPpapiHost;
friend class RenderProcessHostImpl;
// This is private because the only classes that need access to it are made
// friends above. This is only guaranteed to be valid on creation, after that
// this class could outlive the filter.
IPC::MessageFilter* GetFilter();
// This implements IPC::MessageFilter so that we can hide that from child
// classes. Internal keeps a reference to this class, which is why there's a
// weak pointer back. This class could outlive Internal based on what the
// child class does in its OnDestruct method.
Internal* internal_;
IPC::Sender* sender_;
base::Process peer_process_;
std::vector<uint32> message_classes_to_filter_;
struct BrowserMessageFilterTraits {
static void Destruct(const BrowserMessageFilter* filter) {
} // namespace content