/**************************************************************
 * 
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 * 
 *   http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 * 
 *************************************************************/



#include "system.h"

#include <osl/diagnose.h>
#include <osl/semaphor.h>

/*
	Implemetation notes:
	The void* represented by oslSemaphore is used
	to store a WIN32 HANDLE.
*/


/*****************************************************************************/
/* osl_createSemaphore */
/*****************************************************************************/
oslSemaphore SAL_CALL osl_createSemaphore(sal_uInt32 initialCount) 
{
	oslSemaphore Semaphore;

	Semaphore= CreateSemaphore(0, initialCount, INT_MAX, 0);

	/* create failed? */
	if((HANDLE)Semaphore == INVALID_HANDLE_VALUE)
	{
		Semaphore= 0;
	}

	return Semaphore;  
}

/*****************************************************************************/
/* osl_destroySemaphore */
/*****************************************************************************/
void SAL_CALL osl_destroySemaphore(oslSemaphore Semaphore) 
{

	
	if(Semaphore != 0) 
	{
		CloseHandle((HANDLE)Semaphore);
	}

}
			 
/*****************************************************************************/
/* osl_acquireSemaphore */
/*****************************************************************************/
sal_Bool SAL_CALL osl_acquireSemaphore(oslSemaphore Semaphore) 
{
	OSL_ASSERT(Semaphore != 0);

	switch ( WaitForSingleObject( (HANDLE)Semaphore, INFINITE ) )
	{
		case WAIT_OBJECT_0:
			return sal_True;

		default:
			return (sal_False);			
	}
}

/*****************************************************************************/
/* osl_tryToAcquireSemaphore */
/*****************************************************************************/
sal_Bool SAL_CALL osl_tryToAcquireSemaphore(oslSemaphore Semaphore)
{
	OSL_ASSERT(Semaphore != 0);
	return (sal_Bool)(WaitForSingleObject((HANDLE)Semaphore, 0) == WAIT_OBJECT_0);
}


/*****************************************************************************/
/* osl_releaseSemaphore */
/*****************************************************************************/
sal_Bool SAL_CALL osl_releaseSemaphore(oslSemaphore Semaphore) 
{
	OSL_ASSERT(Semaphore != 0);

    /* increase count by one, not interested in previous count */
	return (sal_Bool)(ReleaseSemaphore((HANDLE)Semaphore, 1, NULL) != FALSE);			
}