Semaphore.h

Go to the documentation of this file.

#pragma once
#include <misc/gen/TimeSpec.h>
#include <misc/global.h>
#include <semaphore.h>
 
namespace sf
{
 
class _MISC_CLASS Semaphore
{
  public:
    explicit Semaphore(int initialCount = 0);
 
    ~Semaphore();
 
    bool post();
 
    [[nodiscard]] int value() const;
 
    class _MISC_CLASS Lock
    {
      public:
        inline Lock();
 
        explicit inline Lock(const Semaphore& semaphore, const TimeSpec& timeout);
 
        explicit inline Lock(const Semaphore& semaphore, bool tryWait = false);
 
        inline ~Lock();
 
        bool acquire(const Semaphore& semaphore, const TimeSpec& timeout);
 
        bool acquire(const Semaphore& semaphore, bool tryWait = false);
 
        [[nodiscard]] inline bool isAcquired() const;
 
        void release(bool relinquish = true);
 
      private:
        // Holds the semaphore pointer when signaled.
        const Semaphore* _semaphore;
    };
 
  protected:
    typedef sem_t handle_type;
 
    void release();
 
    handle_type _handle;
};
 
inline Semaphore::Lock::Lock()
  : _semaphore(nullptr)
{}
 
inline Semaphore::Lock::Lock(const Semaphore& semaphore, const TimeSpec& timeout)
  : _semaphore(nullptr)
{
  acquire(semaphore, timeout);
}
 
inline Semaphore::Lock::Lock(const Semaphore& semaphore, bool tryWait)
  : _semaphore(nullptr)
{
  acquire(semaphore, tryWait);
}
 
inline Semaphore::Lock::~Lock()
{
  release();
}
 
inline bool Semaphore::Lock::isAcquired() const
{
  // Object was signaled.
  return _semaphore != nullptr;
}
 
}// namespace sf