libcruft-util/thread/semaphore.hpp

53 lines
1.4 KiB
C++

/*
* 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.
*
* Copyright 2018 Danny Robson <danny@nerdcruft.net>
*/
#ifndef CRUFT_UTIL_THREAD_SEMAPHORE_HPP
#define CRUFT_UTIL_THREAD_SEMAPHORE_HPP
#include <atomic>
namespace util::thread {
/// Explicitly does not conform to BasicLockable.
class semaphore {
public:
semaphore (int initial);
semaphore ();
semaphore (const semaphore&) = delete;
semaphore& operator= (const semaphore&) = delete;
semaphore (semaphore&&) = delete;
semaphore& operator= (semaphore&&) = delete;
int acquire (void);
int acquire (int count);
int release (void);
int release (int count);
auto lock (void) { return acquire (); }
auto unlock (void) { return release (); }
int value (void) const;
int operator++ (void);
int operator-- (void);
private:
std::atomic<int> m_value;
};
};
#endif