Add a Mojo EDK for Chrome that uses one OS pipe per message pipe.

mojo/edk/system/raw_channel.h

Index: mojo/edk/system/raw_channel.h
diff --git a/third_party/mojo/src/mojo/edk/system/raw_channel.h b/mojo/edk/system/raw_channel.h
similarity index 82%
copy from third_party/mojo/src/mojo/edk/system/raw_channel.h
copy to mojo/edk/system/raw_channel.h
index cbcc1b3fc63d543ad03560161d57f611a3e83490..cd2b914673ed79c64284234f5590efed325e063c 100644
--- a/third_party/mojo/src/mojo/edk/system/raw_channel.h
+++ b/mojo/edk/system/raw_channel.h
@@ -41,9 +41,6 @@ namespace system {
 // on which |Init()| is called).
 class MOJO_SYSTEM_IMPL_EXPORT RawChannel {
  public:
-  // This object may be destroyed on any thread (if |Init()| was called, after
-  // |Shutdown()| was called).
-  virtual ~RawChannel();
 
   // The |Delegate| is only accessed on the same thread as the message loop
   // (passed in on creation).
@@ -84,7 +81,12 @@ class MOJO_SYSTEM_IMPL_EXPORT RawChannel {
   // Static factory method. |handle| should be a handle to a
   // (platform-appropriate) bidirectional communication channel (e.g., a socket
   // on POSIX, a named pipe on Windows).
-  static scoped_ptr<RawChannel> Create(embedder::ScopedPlatformHandle handle);
+  static RawChannel* Create(embedder::ScopedPlatformHandle handle);
+
+  // Returns the amount of space needed in the |MessageInTransit|'s
+  // |TransportData|'s "platform handle table" per platform handle (to be
+  // attached to a message). (This amount may be zero.)
+  static size_t GetSerializedPlatformHandleSize();
 
   // This must be called (on an I/O thread) before this object is used. Does
   // *not* take ownership of |delegate|. Both the I/O thread and |delegate| must
@@ -95,6 +97,20 @@ class MOJO_SYSTEM_IMPL_EXPORT RawChannel {
   // This must be called (on the I/O thread) before this object is destroyed.
   void Shutdown();
 
+  // Returns the platform handle for the pipe synchronously.
+
+
+  // Flushes all pending writes synchronously.
+
+
+  // TODO(jam): change above to write it to shared memory and return handle as
+  // writing synchronously won't work for lots of pending data.
+  // Returns any partially read data.
+  // NOTE: After calling this, consider the channel shutdown and don't call into
+  // it anymore
+  embedder::ScopedPlatformHandle ReleaseHandle(
+      std::vector<char>* read_buffer);
+
   // Writes the given message (or schedules it to be written). |message| must
   // have no |Dispatcher|s still attached (i.e.,
   // |SerializeAndCloseDispatchers()| should have been called). This method is
@@ -107,10 +123,14 @@ class MOJO_SYSTEM_IMPL_EXPORT RawChannel {
   // becomes empty (or something like that).
   bool IsWriteBufferEmpty();
 
-  // Returns the amount of space needed in the |MessageInTransit|'s
-  // |TransportData|'s "platform handle table" per platform handle (to be
-  // attached to a message). (This amount may be zero.)
-  virtual size_t GetSerializedPlatformHandleSize() const = 0;
+  bool IsReadBufferEmpty();
+
+  void SetInitialReadBufferData(char* data, size_t size);
+
+  void set_debug_started_sending() { debug_started_sending_ = true; }
+  bool debug_started_sending() { return debug_started_sending_; }
+
+  virtual embedder::PlatformHandle HandleForDebuggingNoLock() = 0;
 
  protected:
   // Result of I/O operations.
@@ -132,6 +152,14 @@ class MOJO_SYSTEM_IMPL_EXPORT RawChannel {
 
     void GetBuffer(char** addr, size_t* size);
 
+    void Reset() {num_valid_bytes_ = 0; }
+
+    // temp for debugging
+    // TODO(jam): pass in a cleaner way to ReleaseHandle, just like shutdown
+    // case.
+    char* buffer() { return &buffer_[0]; }
+    size_t num_valid_bytes() {return num_valid_bytes_;}
+
    private:
     friend class RawChannel;
 
@@ -152,7 +180,7 @@ class MOJO_SYSTEM_IMPL_EXPORT RawChannel {
       size_t size;
     };
 
-    explicit WriteBuffer(size_t serialized_platform_handle_size);
+    WriteBuffer();
     ~WriteBuffer();
 
     // Returns true if there are (more) platform handles to be sent (from the
@@ -179,10 +207,23 @@ class MOJO_SYSTEM_IMPL_EXPORT RawChannel {
     // |OnWriteCompletedNoLock()|.
     void GetBuffers(std::vector<Buffer>* buffers) const;
 
-   private:
+
+
+
+
+    // temp for testing
+    size_t queue_size() {return message_queue_.Size();}
+
+    // TODO(jam): better way of giving buffer on release handle
+    MessageInTransitQueue* message_queue() { return &message_queue_; }
+
+
+
+    // TODO JAM REMOVE AND ADD METHODS
+//   private:
     friend class RawChannel;
 
-    const size_t serialized_platform_handle_size_;
+    size_t serialized_platform_handle_size_;
 
     MessageInTransitQueue message_queue_;
     // Platform handles are sent before the message data, but doing so may
@@ -199,6 +240,11 @@ class MOJO_SYSTEM_IMPL_EXPORT RawChannel {
 
   RawChannel();
 
+  // Shutdown must be called on the IO thread. This object deletes itself once
+  // it's flushed all pending writes and insured that the other side of the pipe
+  // read them.
+  virtual ~RawChannel();
+
   // |result| must not be |IO_PENDING|. Must be called on the I/O thread WITHOUT
   // |write_lock_| held. This object may be destroyed by this call.
   void OnReadCompleted(IOResult io_result, size_t bytes_read);
@@ -210,6 +256,7 @@ class MOJO_SYSTEM_IMPL_EXPORT RawChannel {
 
   base::MessageLoopForIO* message_loop_for_io() { return message_loop_for_io_; }
   base::Lock& write_lock() { return write_lock_; }
+  base::Lock& read_lock() { return read_lock_; }
 
   // Should only be called on the I/O thread.

[yzshen1, 2015/09/23 22:47:09]

Now that ReleaseHandle could be called on non-IO thread and it touches
read-related fields, we can no longer declare in the comments that read-related
fields are only accessed from the IO thread. Besides, we either need to append
"no_lock/NoLock" suffix to more methods, or remove the suffix from existing
methods.

(This comment applies to this class and also raw_channel_win.)

   ReadBuffer* read_buffer() { return read_buffer_.get(); }
@@ -234,6 +281,12 @@ class MOJO_SYSTEM_IMPL_EXPORT RawChannel {
   virtual bool OnReadMessageForRawChannel(
       const MessageInTransit::View& message_view);
 
+
+  // Implementation must write any pending messages synchronously.
+  // TODO(jam): change to return shared memory with pending serialized msgs.
+  virtual embedder::ScopedPlatformHandle ReleaseHandleNoLock(
+      std::vector<char>* read_buffer) = 0;
+
   // Reads into |read_buffer()|.
   // This class guarantees that:
   // - the area indicated by |GetBuffer()| will stay valid until read completion
@@ -289,7 +342,11 @@ class MOJO_SYSTEM_IMPL_EXPORT RawChannel {
   virtual void OnShutdownNoLock(scoped_ptr<ReadBuffer> read_buffer,
                                 scoped_ptr<WriteBuffer> write_buffer) = 0;
 
+  void SendQueuedMessagesNoLock();
+
  private:
+  friend class base::DeleteHelper<RawChannel>;
+
   // Converts an |IO_FAILED_...| for a read to a |Delegate::Error|.
   static Delegate::Error ReadIOResultToError(IOResult io_result);
 
@@ -297,6 +354,8 @@ class MOJO_SYSTEM_IMPL_EXPORT RawChannel {
   // |write_lock_| held. This object may be destroyed by this call.
   void CallOnError(Delegate::Error error);
 
+  void LockAndCallOnError(Delegate::Error error);
+
   // If |io_result| is |IO_SUCCESS|, updates the write buffer and schedules a
   // write operation to run later if there is more to write. If |io_result| is
   // failure or any other error occurs, cancels pending writes and returns
@@ -306,19 +365,51 @@ class MOJO_SYSTEM_IMPL_EXPORT RawChannel {
                               size_t platform_handles_written,
                               size_t bytes_written);
 
+  // Handler for the RAW_CHANNEL_QUIT message.
+  void HandleQuitMessage();
+
+  // Helper method to dispatch messages from the read buffer.
+  // |did_dispatch_message| is true iff it dispatched any messages.
+  // |stop_dispatching| is set to true if the code calling this should stop
+  // dispatching, either because we hit an erorr or the delegate shutdown the
+  // channel.
+  void DispatchMessages(bool* did_dispatch_message, bool* stop_dispatching);
+
   // Set in |Init()| and never changed (hence usable on any thread without
   // locking):
   base::MessageLoopForIO* message_loop_for_io_;
 
+
+
+
+
+  // TODO(jam): one lock only....
+
+
+
+
   // Only used on the I/O thread:
-  Delegate* delegate_;
+
   bool* set_on_shutdown_;
+
+  base::Lock read_lock_;  // Protects read_buffer_.
+  // This is usually only accessed on IO thread, except when ReleaseHandle is
+  // called.
   scoped_ptr<ReadBuffer> read_buffer_;
+  // ditto: usually used on io thread except ReleaseHandle
+  Delegate* delegate_;
+
+  // If grabbing both locks, grab read first.
 
   base::Lock write_lock_;  // Protects the following members.
+  bool write_ready_;
   bool write_stopped_;
   scoped_ptr<WriteBuffer> write_buffer_;
 
+  bool debug_started_sending_;
+
+  bool error_occurred_;
+
   // This is used for posting tasks from write threads to the I/O thread. It
   // must only be accessed under |write_lock_|. The weak pointers it produces
   // are only used/invalidated on the I/O thread.