1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
|
/*
* Copyright (C) 2021 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#define LOG_TAG "FdTrigger"
#include <log/log.h>
#include <poll.h>
#include <android-base/macros.h>
#include "FdTrigger.h"
namespace android {
std::unique_ptr<FdTrigger> FdTrigger::make() {
auto ret = std::make_unique<FdTrigger>();
if (!android::base::Pipe(&ret->mRead, &ret->mWrite)) {
ALOGE("Could not create pipe %s", strerror(errno));
return nullptr;
}
return ret;
}
void FdTrigger::trigger() {
mWrite.reset();
}
bool FdTrigger::isTriggered() {
return mWrite == -1;
}
status_t FdTrigger::triggerablePoll(base::borrowed_fd fd, int16_t event) {
while (true) {
pollfd pfd[]{{.fd = fd.get(), .events = static_cast<int16_t>(event), .revents = 0},
{.fd = mRead.get(), .events = 0, .revents = 0}};
int ret = TEMP_FAILURE_RETRY(poll(pfd, arraysize(pfd), -1));
if (ret < 0) {
return -errno;
}
if (ret == 0) {
continue;
}
if (pfd[1].revents & POLLHUP) {
return -ECANCELED;
}
return pfd[0].revents & event ? OK : DEAD_OBJECT;
}
}
} // namespace android
|