1/*
2 * Copyright (C) 2016 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#ifndef LIBMEMUNREACHABLE_SCOPED_PIPE_H_
18#define LIBMEMUNREACHABLE_SCOPED_PIPE_H_
19
20#include <unistd.h>
21
22#include "log.h"
23
24class ScopedPipe {
25 public:
26  ScopedPipe() : pipefd_{-1, -1} {
27    int ret = pipe2(pipefd_, O_CLOEXEC);
28    if (ret < 0) {
29      LOG_ALWAYS_FATAL("failed to open pipe");
30    }
31  }
32  ~ScopedPipe() {
33    Close();
34  }
35
36  ScopedPipe(ScopedPipe&& other) {
37    SetReceiver(other.ReleaseReceiver());
38    SetSender(other.ReleaseSender());
39  }
40
41  ScopedPipe& operator = (ScopedPipe&& other) {
42    SetReceiver(other.ReleaseReceiver());
43    SetSender(other.ReleaseSender());
44    return *this;
45  }
46
47  void CloseReceiver() {
48    close(ReleaseReceiver());
49  }
50
51  void CloseSender() {
52    close(ReleaseSender());
53  }
54
55  void Close() {
56    CloseReceiver();
57    CloseSender();
58  }
59
60  int Receiver() { return pipefd_[0]; }
61  int Sender() { return pipefd_[1]; }
62
63  int ReleaseReceiver() {
64    int ret = Receiver();
65    SetReceiver(-1);
66    return ret;
67  }
68
69  int ReleaseSender() {
70    int ret = Sender();
71    SetSender(-1);
72    return ret;
73  }
74
75 private:
76  void SetReceiver(int fd) { pipefd_[0] = fd; };
77  void SetSender(int fd) { pipefd_[1] = fd; };
78
79  int pipefd_[2];
80};
81#endif
82