Mojo: More plumbing to support sending handles over MessagePipes.

mojo/system/message_pipe_dispatcher.cc

 // 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.
 
 #include "mojo/system/message_pipe_dispatcher.h"
 
 #include "base/logging.h"
 #include "mojo/system/limits.h"
 #include "mojo/system/memory.h"
 #include "mojo/system/message_pipe.h"
@@ skipping 27 matching lines @@
   lock().AssertAcquired();
   message_pipe_->Close(port_);
   message_pipe_ = NULL;
   return MOJO_RESULT_OK;
 }
 
 MojoResult MessagePipeDispatcher::WriteMessageImplNoLock(
     const void* bytes, uint32_t num_bytes,
     const std::vector<Dispatcher*>* dispatchers,
     MojoWriteMessageFlags flags) {
+  DCHECK(!dispatchers || (dispatchers->size() > 0 &&
+                          dispatchers->size() <= kMaxMessageNumHandles));
+
   lock().AssertAcquired();
 
   if (!VerifyUserPointer<void>(bytes, num_bytes))
     return MOJO_RESULT_INVALID_ARGUMENT;
   if (num_bytes > kMaxMessageNumBytes)
     return MOJO_RESULT_RESOURCE_EXHAUSTED;
 
-  if (dispatchers) {
-    DCHECK_GT(dispatchers->size(), 0u);
-    DCHECK_LE(dispatchers->size(), kMaxMessageNumHandles);
-
-    // TODO(vtl)
-    NOTIMPLEMENTED();
-    return MOJO_RESULT_UNIMPLEMENTED;
-  }
-
   return message_pipe_->WriteMessage(port_,
                                      bytes, num_bytes,
                                      dispatchers,
                                      flags);
 }
 
 MojoResult MessagePipeDispatcher::ReadMessageImplNoLock(
     void* bytes, uint32_t* num_bytes,
     uint32_t max_num_dispatchers,
     std::vector<scoped_refptr<Dispatcher> >* dispatchers,
@@ skipping 20 matching lines @@
   return message_pipe_->AddWaiter(port_, waiter, flags, wake_result);
 }
 
 void MessagePipeDispatcher::RemoveWaiterImplNoLock(Waiter* waiter) {
   lock().AssertAcquired();
   message_pipe_->RemoveWaiter(port_, waiter);
 }
 
 }  // namespace system
 }  // namespace mojo