// EPOS Semaphore Implementation
//
// Author: alexandre
// Documentation: $EPOS/doc/synchronizer			Date: 19 May 2004

#include <abstraction/synchronizer/semaphore.h>
#include <mediator/cpu/ia32.h>
//#include <abstraction/thread/concurrent_thread.h>

__BEGIN_SYS
__BEGIN_IMP

Semaphore::Semaphore(int value)
{
	db<Semaphore>(TRC) << "Semaphore(value= " << value << ")\n";

	Semaphore::counter = value;
}

Semaphore::~Semaphore()
{
	db<Semaphore>(TRC) << "~Semaphore()\n";
}

void Semaphore::p()
{
	db<Semaphore>(TRC) << "Semaphore::p()\n";

	Semaphore::self = Concurrent_Thread::running();

	while (Semaphore::counter == 0)
		Semaphore::self->suspend();

	Semaphore::counter--;
}

void Semaphore::v()
{
	db<Semaphore>(TRC) << "Semaphore::v()\n";
	Semaphore::counter++;

	Semaphore::self = Concurrent_Thread::running();
	Semaphore::self->resume();

}
__END_IMP
__END_SYS