| // 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. |
| |
| #ifndef CONTENT_PUBLIC_BROWSER_BROWSER_MESSAGE_FILTER_H_ |
| #define CONTENT_PUBLIC_BROWSER_BROWSER_MESSAGE_FILTER_H_ |
| |
| #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" |
| #endif |
| |
| namespace base { |
| class TaskRunner; |
| } |
| |
| 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 { |
| public: |
| BrowserMessageFilter(); |
| |
| // These match the corresponding IPC::ChannelProxy::MessageFilter methods and |
| // are always called on the IO thread. |
| virtual void OnFilterAdded(IPC::Channel* channel) {} |
| 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). |
| virtual 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, |
| bool* message_was_ok) = 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_pid_; } |
| |
| void set_peer_pid_for_testing(base::ProcessId peer_pid) { |
| peer_pid_ = peer_pid; |
| } |
| |
| // 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(); |
| |
| protected: |
| virtual ~BrowserMessageFilter(); |
| |
| private: |
| friend class base::RefCountedThreadSafe<BrowserMessageFilter, |
| BrowserMessageFilterTraits>; |
| |
| 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::ChannelProxy::MessageFilter* GetFilter(); |
| |
| // This implements IPC::ChannelProxy::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::Channel* channel_; |
| base::ProcessId peer_pid_; |
| |
| #if defined(OS_WIN) |
| base::Lock peer_handle_lock_; |
| base::ProcessHandle peer_handle_; |
| #endif |
| }; |
| |
| struct BrowserMessageFilterTraits { |
| static void Destruct(const BrowserMessageFilter* filter) { |
| filter->OnDestruct(); |
| } |
| }; |
| |
| } // namespace content |
| |
| #endif // CONTENT_PUBLIC_BROWSER_BROWSER_MESSAGE_FILTER_H_ |