1 /*
2 * Copyright (C) 2019 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17 #pragma once
18
19 #include <sys/socket.h>
20 #include <unistd.h>
21
22 #include <string>
23
24 #include "result.h"
25
26 namespace android {
27 namespace init {
28
29 constexpr size_t kBufferSize = 4096;
30
ReadMessage(int socket)31 inline Result<std::string> ReadMessage(int socket) {
32 char buffer[kBufferSize] = {};
33 auto result = TEMP_FAILURE_RETRY(recv(socket, buffer, sizeof(buffer), 0));
34 if (result == 0) {
35 return Error();
36 } else if (result < 0) {
37 return ErrnoError();
38 }
39 return std::string(buffer, result);
40 }
41
42 template <typename T>
SendMessage(int socket,const T & message)43 Result<void> SendMessage(int socket, const T& message) {
44 std::string message_string;
45 if (!message.SerializeToString(&message_string)) {
46 return Error() << "Unable to serialize message";
47 }
48
49 if (message_string.size() > kBufferSize) {
50 return Error() << "Serialized message too long to send";
51 }
52
53 if (auto result =
54 TEMP_FAILURE_RETRY(send(socket, message_string.c_str(), message_string.size(), 0));
55 result != static_cast<long>(message_string.size())) {
56 return ErrnoError() << "send() failed to send message contents";
57 }
58 return {};
59 }
60
61 } // namespace init
62 } // namespace android
63