1 // Copyright 2014 The Crashpad Authors. All rights reserved.
2 //
3 // Licensed under the Apache License, Version 2.0 (the "License");
4 // you may not use this file except in compliance with the License.
5 // You may obtain a copy of the License at
6 //
7 //     http://www.apache.org/licenses/LICENSE-2.0
8 //
9 // Unless required by applicable law or agreed to in writing, software
10 // distributed under the License is distributed on an "AS IS" BASIS,
11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 // See the License for the specific language governing permissions and
13 // limitations under the License.
14 
15 #include "util/synchronization/semaphore.h"
16 
17 #include <cmath>
18 
19 #include "base/logging.h"
20 
21 namespace crashpad {
22 
Semaphore(int value)23 Semaphore::Semaphore(int value)
24     : semaphore_(dispatch_semaphore_create(value)) {
25   CHECK(semaphore_) << "dispatch_semaphore_create";
26 }
27 
~Semaphore()28 Semaphore::~Semaphore() {
29   dispatch_release(semaphore_);
30 }
31 
Wait()32 void Semaphore::Wait() {
33   CHECK_EQ(dispatch_semaphore_wait(semaphore_, DISPATCH_TIME_FOREVER), 0);
34 }
35 
TimedWait(double seconds)36 bool Semaphore::TimedWait(double seconds) {
37   DCHECK_GE(seconds, 0.0);
38 
39   if (std::isinf(seconds)) {
40     Wait();
41     return true;
42   }
43 
44   const dispatch_time_t timeout =
45       dispatch_time(DISPATCH_TIME_NOW, seconds * NSEC_PER_SEC);
46   return dispatch_semaphore_wait(semaphore_, timeout) == 0;
47 }
48 
Signal()49 void Semaphore::Signal() {
50   dispatch_semaphore_signal(semaphore_);
51 }
52 
53 }  // namespace crashpad
54