util/system/sem.h


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#pragma once

#include "defaults.h"

#include <util/generic/ptr.h> 
 
//named sempahore 
class TSemaphore { 
public: 
    TSemaphore(const char* name, ui32 maxFreeCount); 
    ~TSemaphore();

    //Increase the semaphore counter. 
    void Release() noexcept;

    //Keep a thread held while the semaphore counter is equal 0. 
    void Acquire() noexcept;

    //Try to enter the semaphore gate. A non-blocking variant of Acquire. 
    //Returns 'true' if the semaphore counter decreased 
    bool TryAcquire() noexcept;

private: 
    class TImpl; 
    THolder<TImpl> Impl_; 
};
 
//unnamed semaphore, faster, than previous 
class TFastSemaphore { 
public: 
    TFastSemaphore(ui32 maxFreeCount); 
    ~TFastSemaphore();
 
    void Release() noexcept;
    void Acquire() noexcept;
    bool TryAcquire() noexcept;
 
private: 
    class TImpl; 
    THolder<TImpl> Impl_; 
};