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

mojo/edk/system/data_pipe_consumer_dispatcher.h

 // Copyright 2013 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 MOJO_EDK_SYSTEM_DATA_PIPE_CONSUMER_DISPATCHER_H_
 #define MOJO_EDK_SYSTEM_DATA_PIPE_CONSUMER_DISPATCHER_H_
 
 #include "base/memory/ref_counted.h"
+#include "mojo/edk/system/awakable_list.h"
 #include "mojo/edk/system/dispatcher.h"
+#include "mojo/edk/system/raw_channel.h"
 #include "mojo/edk/system/system_impl_export.h"
 #include "mojo/public/cpp/system/macros.h"
 
 namespace mojo {
 namespace system {
 
-class DataPipe;
-
 // This is the |Dispatcher| implementation for the consumer handle for data
 // pipes (created by the Mojo primitive |MojoCreateDataPipe()|). This class is
 // thread-safe.
 class MOJO_SYSTEM_IMPL_EXPORT DataPipeConsumerDispatcher final
-    : public Dispatcher {
+    : public Dispatcher, public RawChannel::Delegate {
  public:
-  static scoped_refptr<DataPipeConsumerDispatcher> Create() {
-    return make_scoped_refptr(new DataPipeConsumerDispatcher());
+  static scoped_refptr<DataPipeConsumerDispatcher> Create(
+      const MojoCreateDataPipeOptions& options) {
+    return make_scoped_refptr(new DataPipeConsumerDispatcher(options));
   }
 
   // Must be called before any other methods.
-  void Init(scoped_refptr<DataPipe> data_pipe) MOJO_NOT_THREAD_SAFE;
+  void Init(embedder::ScopedPlatformHandle message_pipe);
 
   // |Dispatcher| public methods:
   Type GetType() const override;
 
   // The "opposite" of |SerializeAndClose()|. (Typically this is called by
   // |Dispatcher::Deserialize()|.)
   static scoped_refptr<DataPipeConsumerDispatcher>
-  Deserialize(Channel* channel, const void* source, size_t size);
-
-  // Get access to the |DataPipe| for testing.
-  DataPipe* GetDataPipeForTest();
+  Deserialize(const void* source,
+              size_t size,
+              embedder::PlatformHandleVector* platform_handles);
 
  private:
-  DataPipeConsumerDispatcher();
+  DataPipeConsumerDispatcher(const MojoCreateDataPipeOptions& options);
   ~DataPipeConsumerDispatcher() override;
 
+  void InitOnIO();
+  void CloseOnIO();
+
   // |Dispatcher| protected methods:
   void CancelAllAwakablesNoLock() override;
   void CloseImplNoLock() override;
   scoped_refptr<Dispatcher> CreateEquivalentDispatcherAndCloseImplNoLock()
       override;
   MojoResult ReadDataImplNoLock(UserPointer<void> elements,
                                 UserPointer<uint32_t> num_bytes,
                                 MojoReadDataFlags flags) override;
   MojoResult BeginReadDataImplNoLock(UserPointer<const void*> buffer,
                                      UserPointer<uint32_t> buffer_num_bytes,
                                      MojoReadDataFlags flags) override;
   MojoResult EndReadDataImplNoLock(uint32_t num_bytes_read) override;
   HandleSignalsState GetHandleSignalsStateImplNoLock() const override;
   MojoResult AddAwakableImplNoLock(Awakable* awakable,
                                    MojoHandleSignals signals,
                                    uint32_t context,
                                    HandleSignalsState* signals_state) override;
   void RemoveAwakableImplNoLock(Awakable* awakable,
                                 HandleSignalsState* signals_state) override;
-  void StartSerializeImplNoLock(Channel* channel,
-                                size_t* max_size,
-                                size_t* max_platform_handles) override
-      MOJO_NOT_THREAD_SAFE;
+  void StartSerializeImplNoLock(size_t* max_size,
+                                size_t* max_platform_handles) override;
   bool EndSerializeAndCloseImplNoLock(
-      Channel* channel,
       void* destination,
       size_t* actual_size,
-      embedder::PlatformHandleVector* platform_handles) override
-      MOJO_NOT_THREAD_SAFE;
+      embedder::PlatformHandleVector* platform_handles) override;
+  void TransportStarted() override;
+  void TransportEnded() override;
   bool IsBusyNoLock() const override;
 
-  // This will be null if closed.
-  scoped_refptr<DataPipe> data_pipe_ MOJO_GUARDED_BY(mutex());
+  // |RawChannel::Delegate methods:
+  void OnReadMessage(
+    const MessageInTransit::View& message_view,
+    embedder::ScopedPlatformHandleVectorPtr platform_handles) override;
+  void OnError(Error error) override;
+
+  // See comment in MessagePipeDispatcher for this method.
+  void SerializeInternal();
+
+  MojoCreateDataPipeOptions options_;
+
+  // Protected by |lock()|:
+  RawChannel* channel_;  // This will be null if closed.
+
+  // Queue of incoming messages.
+  std::vector<char> data_;
+  AwakableList awakable_list_;
+
+  // if DispatcherTransport crated. must be set before lock() is called to avoid
+  // deadlocks with RawChannel calling us.
+  base::Lock started_transport_;
+
+  bool calling_init_;
+
+  bool in_two_phase_read_;
+  uint32_t two_phase_max_bytes_read_;
+
+  bool error_;
+
+  bool serialized_;
+  std::vector<char> serialized_read_buffer_;
+  embedder::ScopedPlatformHandle serialized_platform_handle_;
 
   MOJO_DISALLOW_COPY_AND_ASSIGN(DataPipeConsumerDispatcher);
 };
 
 }  // namespace system
 }  // namespace mojo
 
 #endif  // MOJO_EDK_SYSTEM_DATA_PIPE_CONSUMER_DISPATCHER_H_