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
|
/*
* Copyright 2019 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.
*/
#include "reactive_semaphore.h"
#include <error.h>
#include <string.h>
#include <sys/eventfd.h>
#include <unistd.h>
#include <functional>
#include "os/linux_generic/linux.h"
#include "os/log.h"
namespace bluetooth {
namespace os {
ReactiveSemaphore::ReactiveSemaphore(unsigned int value) : fd_(eventfd(value, EFD_SEMAPHORE | EFD_NONBLOCK)) {
ASSERT(fd_ != -1);
}
ReactiveSemaphore::~ReactiveSemaphore() {
int close_status;
RUN_NO_INTR(close_status = close(fd_));
ASSERT_LOG(close_status != -1, "close failed: %s", strerror(errno));
}
void ReactiveSemaphore::Decrease() {
uint64_t val = 0;
auto read_result = eventfd_read(fd_, &val);
ASSERT_LOG(read_result != -1, "decrease failed: %s", strerror(errno));
}
void ReactiveSemaphore::Increase() {
uint64_t val = 1;
auto write_result = eventfd_write(fd_, val);
ASSERT_LOG(write_result != -1, "increase failed: %s", strerror(errno));
}
int ReactiveSemaphore::GetFd() {
return fd_;
}
} // namespace os
} // namespace bluetooth
|
