Make the fuchsia mojo/public repo the source of truth.

mojo/public/cpp/system/buffer.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.
-
-// This file provides a C++ wrapping around the Mojo C API for shared buffers,
-// replacing the prefix of "Mojo" with a "mojo" namespace, and using more
-// strongly-typed representations of |MojoHandle|s.
-//
-// Please see "mojo/public/c/include/mojo/system/buffer.h" for complete
-// documentation of the API.
-
-#ifndef MOJO_PUBLIC_CPP_SYSTEM_BUFFER_H_
-#define MOJO_PUBLIC_CPP_SYSTEM_BUFFER_H_
-
-#include <assert.h>
-#include <mojo/system/buffer.h>
-
-#include "mojo/public/cpp/system/handle.h"
-#include "mojo/public/cpp/system/macros.h"
-
-namespace mojo {
-
-// A strongly-typed representation of a |MojoHandle| referring to a shared
-// buffer.
-class SharedBufferHandle : public Handle {
- public:
-  SharedBufferHandle() {}
-  explicit SharedBufferHandle(MojoHandle value) : Handle(value) {}
-
-  // Copying and assignment allowed.
-};
-
-static_assert(sizeof(SharedBufferHandle) == sizeof(Handle),
-              "Bad size for C++ SharedBufferHandle");
-
-typedef ScopedHandleBase<SharedBufferHandle> ScopedSharedBufferHandle;
-static_assert(sizeof(ScopedSharedBufferHandle) == sizeof(SharedBufferHandle),
-              "Bad size for C++ ScopedSharedBufferHandle");
-
-// Creates a shared buffer. See |MojoCreateSharedBuffer()| for complete
-// documentation.
-inline MojoResult CreateSharedBuffer(
-    const MojoCreateSharedBufferOptions* options,
-    uint64_t num_bytes,
-    ScopedSharedBufferHandle* shared_buffer) {
-  assert(shared_buffer);
-  SharedBufferHandle handle;
-  MojoResult rv =
-      MojoCreateSharedBuffer(options, num_bytes, handle.mutable_value());
-  // Reset even on failure (reduces the chances that a "stale"/incorrect handle
-  // will be used).
-  shared_buffer->reset(handle);
-  return rv;
-}
-
-// Maps a part of a buffer (specified by |buffer|, |offset|, and |num_bytes|)
-// into memory. See |MojoMapBuffer()| for complete documentation.
-template <class BufferHandleType>
-inline MojoResult MapBuffer(BufferHandleType buffer,
-                            uint64_t offset,
-                            uint64_t num_bytes,
-                            void** pointer,
-                            MojoMapBufferFlags flags) {
-  assert(buffer.is_valid());
-  return MojoMapBuffer(buffer.value(), offset, num_bytes, pointer, flags);
-}
-
-// Unmaps a part of a buffer that was previously mapped with |MapBuffer()|.
-// See |MojoUnmapBuffer()| for complete documentation.
-inline MojoResult UnmapBuffer(void* pointer) {
-  assert(pointer);
-  return MojoUnmapBuffer(pointer);
-}
-
-// A wrapper class that automatically creates a shared buffer and owns the
-// handle.
-class SharedBuffer {
- public:
-  explicit SharedBuffer(uint64_t num_bytes);
-  SharedBuffer(uint64_t num_bytes,
-               const MojoCreateSharedBufferOptions& options);
-  ~SharedBuffer();
-
-  ScopedSharedBufferHandle handle;
-};
-
-inline SharedBuffer::SharedBuffer(uint64_t num_bytes) {
-  MojoResult result = CreateSharedBuffer(nullptr, num_bytes, &handle);
-  MOJO_ALLOW_UNUSED_LOCAL(result);
-  assert(result == MOJO_RESULT_OK);
-}
-
-inline SharedBuffer::SharedBuffer(
-    uint64_t num_bytes,
-    const MojoCreateSharedBufferOptions& options) {
-  MojoResult result = CreateSharedBuffer(&options, num_bytes, &handle);
-  MOJO_ALLOW_UNUSED_LOCAL(result);
-  assert(result == MOJO_RESULT_OK);
-}
-
-inline SharedBuffer::~SharedBuffer() {
-}
-
-}  // namespace mojo
-
-#endif  // MOJO_PUBLIC_CPP_SYSTEM_BUFFER_H_