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_;
};