SemaphoreUnix.cpp revision 617e2443dfc17fe44fd44c0675d6aad2ffc9df42
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//////////////////////////////////////////////////////////////////////////
// SemaphoreLinux.cpp
//
// This file contains the linux implementation of the Semaphore class
//////////////////////////////////////////////////////////////////////////
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include "Semaphore.h"
#include <semaphore.h>
class OSSemaphore {
public:
sem_t _sem;
};
Semaphore::Semaphore(int maxval)
{
_osSemaphore = new OSSemaphore;
sem_init(&_osSemaphore->_sem, 0, maxval);
}
Semaphore::~Semaphore()
{
sem_destroy(&_osSemaphore->_sem);
delete _osSemaphore;
}
void Semaphore::acquire()
{
// blocks until value !=0, and decrements the value
sem_wait(&_osSemaphore->_sem);
}
void Semaphore::release()
{
// increments the value by 1
sem_post(&_osSemaphore->_sem);
}
bool Semaphore::acquireTry()
{
// try to acquire the semaphore: return 'true' if succeded
return (sem_trywait(&_osSemaphore->_sem) == 0);
}