platform_system_core/libmemunreachable/Semaphore.h
Colin Cross bcb4ed3eaa imprecise mark and sweep native memory leak detector
libmemunreachable uses an imprecise mark and sweep pass over all memory
allocated by jemalloc in order to find unreachable allocations.

Change-Id: Ia70bbf31f5b40ff71dab28cfd6cd06c5ef01a2d4
2016-02-08 17:08:49 -08:00

56 lines
1.3 KiB
C++

/*
* Copyright (C) 2016 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.
*/
#ifndef LIBMEMUNREACHABLE_SEMAPHORE_H_
#define LIBMEMUNREACHABLE_SEMAPHORE_H_
#include <chrono>
#include <mutex>
#include "android-base/macros.h"
class Semaphore {
public:
Semaphore(int count = 0) : count_(count) {}
~Semaphore() = default;
void Wait(std::chrono::milliseconds ms) {
std::unique_lock<std::mutex> lk(m_);
cv_.wait_for(lk, ms, [&]{
if (count_ > 0) {
count_--;
return true;
}
return false;
});
}
void Post() {
{
std::lock_guard<std::mutex> lk(m_);
count_++;
}
cv_.notify_one();
}
private:
DISALLOW_COPY_AND_ASSIGN(Semaphore);
int count_;
std::mutex m_;
std::condition_variable cv_;
};
#endif // LIBMEMUNREACHABLE_SEMAPHORE_H_