Mojo: (Theoretically) implement the read side of platform handle passing.

mojo/embedder/platform_channel_utils_posix.h

 // Copyright 2014 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_EMBEDDER_PLATFORM_CHANNEL_UTILS_POSIX_H_
 #define MOJO_EMBEDDER_PLATFORM_CHANNEL_UTILS_POSIX_H_
 
 #include <stddef.h>
 #include <sys/types.h>  // For |ssize_t|.
 
 #include <vector>
 
 #include "base/memory/scoped_ptr.h"
 #include "mojo/embedder/platform_handle.h"
+#include "mojo/embedder/platform_handle_vector.h"
 #include "mojo/system/system_impl_export.h"
 
 struct iovec;  // Declared in <sys/uio.h>.
 
 namespace mojo {
 namespace embedder {
 
 // The maximum number of handles that can be sent "at once" using
 // |PlatformChannelSendHandles()|.
 // TODO(vtl): This number is taken from ipc/file_descriptor_set_posix.h:
 // |FileDescriptorSet::kMaxDescriptorsPerMessage|. Where does it come from?
 const size_t kPlatformChannelMaxNumHandles = 7;
 
-typedef std::vector<PlatformHandle> PlatformHandleVector;
-
 // Use these to write to a socket created using |PlatformChannelPair| (or
 // equivalent). These are like |write()| and |writev()|, but handle |EINTR| and
 // never raise |SIGPIPE|. (Note: On Mac, the suppression of |SIGPIPE| is set up
 // by |PlatformChannelPair|.)
 MOJO_SYSTEM_IMPL_EXPORT ssize_t PlatformChannelWrite(PlatformHandle h,
                                                      const void* bytes,
                                                      size_t num_bytes);
 MOJO_SYSTEM_IMPL_EXPORT ssize_t PlatformChannelWritev(PlatformHandle h,
                                                       struct iovec* iov,
                                                       size_t num_iov);
@@ skipping 15 matching lines @@
 MOJO_SYSTEM_IMPL_EXPORT ssize_t PlatformChannelRecvmsg(
     PlatformHandle h,
     void* buf,
     size_t num_bytes,
     scoped_ptr<PlatformHandleVector>* handles);
 
 }  // namespace embedder
 }  // namespace mojo
 
 #endif  // MOJO_EMBEDDER_PLATFORM_CHANNEL_UTILS_POSIX_H_