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diff --git a/chromium/mojo/embedder/platform_channel_pair.h b/chromium/mojo/embedder/platform_channel_pair.h
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index 00000000000..126bd3d98e1
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+++ b/chromium/mojo/embedder/platform_channel_pair.h
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+// 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_PAIR_H_
+#define MOJO_EMBEDDER_PLATFORM_CHANNEL_PAIR_H_
+
+#include "base/macros.h"
+#include "base/memory/scoped_ptr.h"
+#include "base/process/launch.h"
+#include "build/build_config.h"
+#include "mojo/embedder/scoped_platform_handle.h"
+#include "mojo/system/system_impl_export.h"
+
+namespace base {
+class CommandLine;
+}
+
+namespace mojo {
+namespace embedder {
+
+// It would be nice to refactor base/process/launch.h to have a more platform-
+// independent way of representing handles that are passed to child processes.
+#if defined(OS_WIN)
+typedef base::HandlesToInheritVector HandlePassingInformation;
+#elif defined(OS_POSIX)
+typedef base::FileHandleMappingVector HandlePassingInformation;
+#else
+#error "Unsupported."
+#endif
+
+// This is used to create a pair of |PlatformHandle|s that are connected by a
+// suitable (platform-specific) bidirectional "pipe" (e.g., socket on POSIX,
+// named pipe on Windows). The resulting handles can then be used in the same
+// process (e.g., in tests) or between processes. (The "server" handle is the
+// one that will be used in the process that created the pair, whereas the
+// "client" handle is the one that will be used in a different process.)
+//
+// This class provides facilities for passing the client handle to a child
+// process. The parent should call |PrepareToPassClientHandlelToChildProcess()|
+// to get the data needed to do this, spawn the child using that data, and then
+// call |ChildProcessLaunched()|. Note that on Windows this facility (will) only
+// work on Vista and later (TODO(vtl)).
+//
+// Note: |PlatformChannelPair()|, |PassClientHandleFromParentProcess()| and
+// |PrepareToPassClientHandleToChildProcess()| have platform-specific
+// implementations.
+//
+// Note: On POSIX platforms, to write to the "pipe", use
+// |PlatformChannel{Write,Writev}()| (from platform_channel_utils_posix.h)
+// instead of |write()|, |writev()|, etc. Otherwise, you have to worry about
+// platform differences in suppressing |SIGPIPE|.
+class MOJO_SYSTEM_IMPL_EXPORT PlatformChannelPair {
+ public:
+  PlatformChannelPair();
+  ~PlatformChannelPair();
+
+  ScopedPlatformHandle PassServerHandle();
+
+  // For in-process use (e.g., in tests or to pass over another channel).
+  ScopedPlatformHandle PassClientHandle();
+
+  // To be called in the child process, after the parent process called
+  // |PrepareToPassClientHandleToChildProcess()| and launched the child (using
+  // the provided data), to create a client handle connected to the server
+  // handle (in the parent process).
+  static ScopedPlatformHandle PassClientHandleFromParentProcess(
+      const base::CommandLine& command_line);
+
+  // Prepares to pass the client channel to a new child process, to be launched
+  // using |LaunchProcess()| (from base/launch.h). Modifies |*command_line| and
+  // |*handle_passing_info| as needed.
+  // Note: For Windows, this method only works on Vista and later.
+  void PrepareToPassClientHandleToChildProcess(
+      base::CommandLine* command_line,
+      HandlePassingInformation* handle_passing_info) const;
+
+  // To be called once the child process has been successfully launched, to do
+  // any cleanup necessary.
+  void ChildProcessLaunched();
+
+ private:
+  static const char kMojoPlatformChannelHandleSwitch[];
+
+  ScopedPlatformHandle server_handle_;
+  ScopedPlatformHandle client_handle_;
+
+  DISALLOW_COPY_AND_ASSIGN(PlatformChannelPair);
+};
+
+}  // namespace embedder
+}  // namespace mojo
+
+#endif  // MOJO_EMBEDDER_PLATFORM_CHANNEL_PAIR_H_