1/*
2 * Copyright (C) 2017 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#include "PipeRelay.h"
18
19#include <sys/socket.h>
20#include <utils/Thread.h>
21
22namespace android {
23namespace lshal {
24
25struct PipeRelay::RelayThread : public Thread {
26    explicit RelayThread(int fd, std::ostream &os);
27
28    bool threadLoop() override;
29
30private:
31    int mFd;
32    std::ostream &mOutStream;
33
34    DISALLOW_COPY_AND_ASSIGN(RelayThread);
35};
36
37////////////////////////////////////////////////////////////////////////////////
38
39PipeRelay::RelayThread::RelayThread(int fd, std::ostream &os)
40    : mFd(fd),
41      mOutStream(os) {
42}
43
44bool PipeRelay::RelayThread::threadLoop() {
45    char buffer[1024];
46    ssize_t n = read(mFd, buffer, sizeof(buffer));
47
48    if (n <= 0) {
49        return false;
50    }
51
52    mOutStream.write(buffer, n);
53
54    return true;
55}
56
57////////////////////////////////////////////////////////////////////////////////
58
59PipeRelay::PipeRelay(std::ostream &os)
60    : mOutStream(os),
61      mInitCheck(NO_INIT) {
62    int res = socketpair(AF_UNIX, SOCK_STREAM, 0 /* protocol */, mFds);
63
64    if (res < 0) {
65        mInitCheck = -errno;
66        return;
67    }
68
69    mThread = new RelayThread(mFds[0], os);
70    mInitCheck = mThread->run("RelayThread");
71}
72
73void PipeRelay::CloseFd(int *fd) {
74    if (*fd >= 0) {
75        close(*fd);
76        *fd = -1;
77    }
78}
79
80PipeRelay::~PipeRelay() {
81    if (mFds[1] >= 0) {
82        shutdown(mFds[1], SHUT_WR);
83    }
84
85    if (mFds[0] >= 0) {
86        shutdown(mFds[0], SHUT_RD);
87    }
88
89    if (mThread != NULL) {
90        mThread->join();
91        mThread.clear();
92    }
93
94    CloseFd(&mFds[1]);
95    CloseFd(&mFds[0]);
96}
97
98status_t PipeRelay::initCheck() const {
99    return mInitCheck;
100}
101
102int PipeRelay::fd() const {
103    return mFds[1];
104}
105
106}  // namespace lshal
107}  // namespace android
108