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

mojo/public/c/include/mojo/bindings/message.h

-// Copyright 2016 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_PUBLIC_C_INCLUDE_MOJO_BINDINGS_MESSAGE_H_
-#define MOJO_PUBLIC_C_INCLUDE_MOJO_BINDINGS_MESSAGE_H_
-
-#include <mojo/bindings/struct.h>
-#include <mojo/bindings/validation.h>
-#include <mojo/macros.h>
-#include <stdint.h>
-
-MOJO_BEGIN_EXTERN_C
-
-#define MOJOM_MESSAGE_FLAGS_EXPECTS_RESPONSE ((uint32_t)(1 << 0u))
-#define MOJOM_MESSAGE_FLAGS_IS_RESPONSE ((uint32_t)(1 << 1u))
-
-// All mojom messages (over a message pipe) are framed with a MojomMessage as
-// its header.
-// MojomMessage is actually a mojom struct -- we define it here since it's
-// easier to read, and the validation has more to it than simple mojom struct
-// validation.
-struct MojomMessage {
-  // header.version = 0 (version 1 has a request_id)
-  struct MojomStructHeader header;
-  // The ordinal number associated with this message. This is specified
-  // (implicitly, if not explicitly) in the mojom IDL for an interface message
-  // and is used to identify it.
-  uint32_t ordinal;
-  // Described by the MOJOM_MESSAGE_* flags defined above.
-  uint32_t flags;
-};
-MOJO_STATIC_ASSERT(sizeof(struct MojomMessage) == 16,
-                   "struct MojomMessage must be 16 bytes");
-
-// Using |MojomMessage| as a member of this struct could work, but usability
-// would suffer a little while accessing the |header|. MojomMessageWithRequestId
-// is a "newer" version than MojomMessage.
-struct MojomMessageWithRequestId {
-  // header.version = 1
-  struct MojomStructHeader header;
-  // Which message is it?
-  uint32_t ordinal;
-  // Described by the MOJOM_MESSAGE_* flags defined above.
-  uint32_t flags;
-  uint64_t request_id;
-};
-MOJO_STATIC_ASSERT(sizeof(struct MojomMessageWithRequestId) == 24,
-                   "MojomMessageWithRequestId must be 24 bytes");
-
-// Validates that |in_buf| is a valid mojom message. This does not validate the
-// contents of the message's body, only the message header. This function does
-// not validate whether a message should be a kind of request.
-// |in_buf|: can be a MojomMessage or a MojomMessageWithRequestId.
-// |in_buf_size|: number of bytes in |in_buf|.
-MojomValidationResult MojomMessage_ValidateHeader(const void* in_buf,
-                                                  uint32_t in_buf_size);
-
-// Validates that the given message is a request expecting a response. Assumes
-// that the message is already validated by MojomMessage_ValidateHeader().
-MojomValidationResult MojomMessage_ValidateRequestExpectingResponse(
-    const void* in_buf);
-
-// Validates that the given message is a request which isn't expecting a
-// response. Assumes that the message is already validated by
-// MojomMessage_ValidateHeader().
-MojomValidationResult MojomMessage_ValidateRequestWithoutResponse(
-    const void* in_buf);
-
-// Validates that the given message is a response. Assumes taht the message is
-// already validated by MojomMessage_ValidateHeader().
-MojomValidationResult MojomMessage_ValidateResponse(const void* in_buf);
-
-MOJO_END_EXTERN_C
-
-#endif  // MOJO_PUBLIC_C_INCLUDE_MOJO_BINDINGS_MESSAGE_H_