/*
    File        : sema.h
    Date        : 19-Sep-02
    Description : Semaphore handling for the PsiFS module.

    Copyright  1998, 1999, 2000, 2001, 2002 Alexander Thoukydides

    This program is free software; you can redistribute it and/or
    modify it under the terms of the GNU General Public License
    as published by the Free Software Foundation; either version 2
    of the License, or (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program; if not, write to the Free Software
    Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
*/

// Only include header file once
#ifndef SEMA_H
#define SEMA_H

// Include oslib header files
#include "oslib/types.h"

// A semaphore type
typedef bool semaphore;
#define SEMA_CLAIMED ((semaphore) 1)
#define SEMA_RELEASED ((semaphore) 0)

#ifdef __cplusplus
    extern "C" {
#endif

/*
    Parameters  : sema  - The semaphore to claim.
    Returns     : bool  - Was the semaphore claimed.
    Description : Attempt to claim the specified semaphore. This fails if the
                  semaphore has already been claimed.
*/
bool sema_claim(semaphore *sema);

/*
    Parameters  : sema  - The semaphore to release.
    Returns     : void
    Description : Release the specified semaphore. The semaphore must have been
                  claimed previously.
*/
void sema_release(semaphore *sema);

#ifdef __cplusplus
    }
#endif

#endif
