[mojo-edk] Explicitly serialise HANDLEs into messages instead of PlatformHandles.

mojo/edk/system/message_pipe_dispatcher.cc

 // 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.
 
 #include "mojo/edk/system/message_pipe_dispatcher.h"
 
 #include <limits>
 #include <memory>
 
 #include "base/logging.h"
@@ skipping 271 matching lines @@
     CHECK(handles);
     std::vector<DispatcherInTransit> dispatchers(header->num_dispatchers);
     size_t data_payload_index = sizeof(MessageHeader) +
         header->num_dispatchers * sizeof(DispatcherHeader);
     if (data_payload_index > header->header_size)
       return MOJO_RESULT_UNKNOWN;
     const char* dispatcher_data = reinterpret_cast<const char*>(
         dispatcher_headers + header->num_dispatchers);
     size_t port_index = 0;
     size_t platform_handle_index = 0;
+    ScopedPlatformHandleVectorPtr msg_handles = msg->TakeHandles();
     for (size_t i = 0; i < header->num_dispatchers; ++i) {
       const DispatcherHeader& dh = dispatcher_headers[i];
       Type type = static_cast<Type>(dh.type);
 
       size_t next_payload_index = data_payload_index + dh.num_bytes;
       if (msg->num_payload_bytes() < next_payload_index ||
           next_payload_index < data_payload_index) {
         return MOJO_RESULT_UNKNOWN;
       }
 
       size_t next_port_index = port_index + dh.num_ports;
       if (msg->num_ports() < next_port_index || next_port_index < port_index)
         return MOJO_RESULT_UNKNOWN;
 
       size_t next_platform_handle_index =
           platform_handle_index + dh.num_platform_handles;
-      if (msg->num_handles() < next_platform_handle_index ||

[Ken Rockot(use gerrit already), 2016/05/25 15:48:12]

nit: Could you create a local num_handles near msg_handles to store this
(msg_handles ? msg_handles->size() : 0) so these conditions are more readable?

[Anand Mistry (off Chromium), 2016/05/25 23:36:38]

Done.

+      if ((msg_handles && msg_handles->size() < next_platform_handle_index) ||
           next_platform_handle_index < platform_handle_index) {
         return MOJO_RESULT_UNKNOWN;
       }
 
       PlatformHandle* out_handles =
-          msg->num_handles() ? msg->handles() + platform_handle_index : nullptr;
+          (msg_handles && msg_handles->size()) ?
+          msg_handles->data() + platform_handle_index : nullptr;
       dispatchers[i].dispatcher = Dispatcher::Deserialize(
           type, dispatcher_data, dh.num_bytes, msg->ports() + port_index,
           dh.num_ports, out_handles, dh.num_platform_handles);
       if (!dispatchers[i].dispatcher)
         return MOJO_RESULT_UNKNOWN;
 
       dispatcher_data += dh.num_bytes;
       data_payload_index = next_payload_index;
       port_index = next_port_index;
       platform_handle_index = next_platform_handle_index;
@@ skipping 217 matching lines @@
                << " endpoint " << endpoint_ << " [port=" << port_.name() << "]";
     }
   }
 #endif
 
   awakables_.AwakeForStateChange(GetHandleSignalsStateNoLock());
 }
 
 }  // namespace edk
 }  // namespace mojo