1// Copyright 2016 The Chromium Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style license that can be
3// found in the LICENSE file.
4
5#ifndef MOJO_EDK_SYSTEM_BROKER_MESSAGES_H_
6#define MOJO_EDK_SYSTEM_BROKER_MESSAGES_H_
7
8#include "mojo/edk/system/channel.h"
9
10namespace mojo {
11namespace edk {
12
13#pragma pack(push, 1)
14
15enum BrokerMessageType : uint32_t {
16  INIT,
17  BUFFER_REQUEST,
18  BUFFER_RESPONSE,
19};
20
21struct BrokerMessageHeader {
22  BrokerMessageType type;
23  uint32_t padding;
24};
25
26static_assert(sizeof(BrokerMessageHeader) % kChannelMessageAlignment == 0,
27              "Invalid header size.");
28
29struct BufferRequestData {
30  uint32_t size;
31};
32
33#pragma pack(pop)
34
35template <typename T>
36inline Channel::MessagePtr CreateBrokerMessage(BrokerMessageType type,
37                                               size_t num_handles,
38                                               T** out_message_data) {
39  const size_t message_size = sizeof(BrokerMessageHeader) + sizeof(T);
40  Channel::MessagePtr message(new Channel::Message(message_size, num_handles));
41  BrokerMessageHeader* header =
42      reinterpret_cast<BrokerMessageHeader*>(message->mutable_payload());
43  header->type = type;
44  header->padding = 0;
45  *out_message_data = reinterpret_cast<T*>(header + 1);
46  return message;
47}
48
49inline Channel::MessagePtr CreateBrokerMessage(
50    BrokerMessageType type,
51    size_t num_handles,
52    std::nullptr_t** dummy_out_data) {
53  Channel::MessagePtr message(
54      new Channel::Message(sizeof(BrokerMessageHeader), num_handles));
55  BrokerMessageHeader* header =
56      reinterpret_cast<BrokerMessageHeader*>(message->mutable_payload());
57  header->type = type;
58  header->padding = 0;
59  return message;
60}
61
62}  // namespace edk
63}  // namespace mojo
64
65#endif  // MOJO_EDK_SYSTEM_BROKER_MESSAGES_H_
66