Allow data pipe producer/consumer handles to be re-sent.

mojo/edk/system/data_pipe_impl.h

 // Copyright 2015 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_IMPL_H_
 #define MOJO_EDK_SYSTEM_DATA_PIPE_IMPL_H_
 
 #include <stdint.h>
 
 #include "base/compiler_specific.h"
@@ skipping 72 matching lines @@
       void* destination,
       size_t* actual_size,
       embedder::PlatformHandleVector* platform_handles) = 0;
 
   virtual bool OnReadMessage(unsigned port, MessageInTransit* message) = 0;
   virtual void OnDetachFromChannel(unsigned port) = 0;
 
  protected:
   DataPipeImpl() : owner_() {}
 
+  // Helper to convert the given circular buffer into messages. The input is a
+  // circular buffer |buffer| (with appropriate element size and capacity), with
+  // current contents starting at |start_index| of length |current_num_bytes|.
+  // This will convert all of the contents.
+  void ConvertDataToMessages(const char* buffer,
+                             size_t* start_index,
+                             size_t* current_num_bytes,
+                             MessageInTransitQueue* message_queue);
+
   DataPipe* owner() const { return owner_; }
 
   const MojoCreateDataPipeOptions& validated_options() const {
     return owner_->validated_options();
   }
   size_t element_num_bytes() const { return owner_->element_num_bytes(); }
   size_t capacity_num_bytes() const { return owner_->capacity_num_bytes(); }
   bool producer_open() const { return owner_->producer_open_no_lock(); }
   bool consumer_open() const { return owner_->consumer_open_no_lock(); }
   uint32_t producer_two_phase_max_num_bytes_written() const {
@@ skipping 41 matching lines @@
 struct ALIGNAS(8) SerializedDataPipeConsumerDispatcher {
   // Only validated (and thus canonicalized) options should be serialized.
   // However, the deserializer must revalidate (as with everything received).
   MojoCreateDataPipeOptions validated_options;
 };
 
 }  // namespace system
 }  // namespace mojo
 
 #endif  // MOJO_EDK_SYSTEM_DATA_PIPE_IMPL_H_