mutex.h

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/* ==== mutex.h ============================================================
 * Copyright (c) 1993 by Chris Provenzano, [e-mail]
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *  This product includes software developed by Chris Provenzano.
 * 4. The name of Chris Provenzano may not be used to endorse or promote 
 *	  products derived from this software without specific prior written
 *	  permission.
 *
 * THIS SOFTWARE IS PROVIDED BY CHRIS PROVENZANO ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL CHRIS PROVENZANO BE LIABLE FOR ANY 
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR 
 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 
 * SUCH DAMAGE.
 *
 * $Id$
 *
 * Description : mutex header.
 *
 *  1.00 93/07/20 proven
 *      -Started coding this file.
 */
 
/*
 * New mutex structures
 */
enum pthread_mutextype {
	MUTEX_TYPE_STATIC_FAST		= 0,
	MUTEX_TYPE_FAST				= 1,
	MUTEX_TYPE_COUNTING_FAST	= 2,	/* Recursive */
	MUTEX_TYPE_METERED			= 3,
	MUTEX_TYPE_DEBUG			= 4, 	/* This will have lots of options */
	MUTEX_TYPE_MAX
};

#define PTHREAD_MUTEXTYPE_FAST			1
#define PTHREAD_MUTEXTYPE_DEBUG			4
#define PTHREAD_MUTEXTYPE_RECURSIVE		2

union pthread_mutex_data {
	void 					  * m_ptr;
	int							m_count;
};

typedef struct pthread_mutex {
	enum pthread_mutextype		m_type;
	struct pthread_queue		m_queue;
	struct pthread			  * m_owner;
	semaphore					m_lock;	
	union pthread_mutex_data    m_data;
	long						m_flags;
} pthread_mutex_t;

typedef struct pthread_mutexattr {
	enum pthread_mutextype		m_type;
	long						m_flags;
} pthread_mutexattr_t;

/*
 * Flags for mutexes.
 */
#define MUTEX_FLAGS_PRIVATE		0x01
#define MUTEX_FLAGS_INITED		0x02
#define MUTEX_FLAGS_BUSY		0x04

/*
 * Static mutex initialization values.
 */
#define PTHREAD_MUTEX_INITIALIZER	\
{ MUTEX_TYPE_STATIC_FAST, PTHREAD_QUEUE_INITIALIZER, \
	 NULL, SEMAPHORE_CLEAR, { NULL }, MUTEX_FLAGS_INITED }

/*
 * New functions
 */

__BEGIN_DECLS

int     pthread_mutex_init  	__P_((pthread_mutex_t *, const pthread_mutexattr_t *));
int     pthread_mutex_lock      __P_((pthread_mutex_t *));
int     pthread_mutex_unlock    __P_((pthread_mutex_t *));
int     pthread_mutex_trylock   __P_((pthread_mutex_t *));
int     pthread_mutex_destroy   __P_((pthread_mutex_t *));

__END_DECLS