semaphore.cc

来自「AVR 单片机程序设计用到的模拟器」· CC 代码 · 共 36 行

/* $Id: Semaphore.cc,v 1.2 2000/09/24 13:54:53 pure Exp $ */

#include "Semaphore.h"

Semaphore::Semaphore() : Mutex()
{
	if (pthread_cond_init(&cond, NULL))
		throw;
	value = 0;
}
	
Semaphore::~Semaphore()
{
	pthread_cond_destroy(&cond);
}
	
void Semaphore::signal(int n)
{    	
	value += n;
	pthread_cond_signal(&cond);
}
	
void Semaphore::wait()
{
	lock();
	while (value <= 0) 
		pthread_cond_wait(&cond, (pthread_mutex_t *) this);
	value--;
	unlock();
}
	
Semaphore::operator pthread_cond_t* ()
{
	return &cond;
}