Coherent4.2.10/include/sys/sem.h

/* (-lgl
 *	Coherent 386 release 4.2
 *	Copyright (c) 1982, 1993 by Mark Williams Company.
 *	All rights reserved. May not be copied without permission.
 *	For copying permission and licensing info, write licensing@mwc.com
 -lgl) */

#ifndef __SYS_SEM_H__
#define __SYS_SEM_H__

/*
 * IPC Semaphore Facility
 */

#include <common/feature.h>
#include <common/ccompat.h>
#include <common/__pid.h>
#include <common/__time.h>
#include <common/__size.h>
#include <common/_imode.h>


/*
 * Semaphore Operation Flags.
 */

#define SEM_UNDO 010000		/* set up adjust on exit entry */


/*
 * Semctl Command Definitions.
 */

#define	GETNCNT	3		/* get semncnt */
#define	GETPID	4		/* get sempid  */
#define	GETVAL	5		/* get semval  */
#define	GETALL	6		/* get all semval's */
#define	GETZCNT 7		/* get semzcnt */
#define	SETVAL	8		/* set semval  */
#define	SETALL	9		/* set all semval's */


/*
 * Structure Definitions.
 */

/*
 * There is one semaphore id data structure for each set of semaphores
 * in the system.
 */

#if	_SYSV4

struct semid_ds {
	struct ipc_perm	sem_perm;	/* semaphore permission struct */
	struct sem    *	sem_base;	/* pointer to first semaphore in set */
	unsigned short	sem_nsems;	/* # of semaphores in set */
	__time_t	sem_otime;	/* last semop time */
	long		__pad1;
	__time_t	sem_ctime;	/* last change time */
	long		__pad2;
	long		__pad3 [4];
};

#else

struct semid_ds {
	struct ipc_perm	sem_perm;	/* semaphore permission struct */
	struct sem    *	sem_base;	/* pointer to first semaphore in set */
	unsigned short	sem_nsems;	/* # of semaphores in set */
	__time_t	sem_otime;	/* last semop time */
	__time_t	sem_ctime;	/* last change time */
};

#endif


/*
 * There is one semaphore structure for each semaphore in the system.
 */

struct sem {
	unsigned short	semval;		/* semaphore value */
	short		sempid;		/* pid of last operation */
	unsigned short	semncnt;	/* # awaiting semval > cval */
	unsigned short	semzcnt;	/* # awaiting semval = 0 */
};


/*
 * User semaphore template for semop system calls.
 */

struct sembuf {
	unsigned short	sem_num;	/* semaphore # */
	short		sem_op;		/* semaphore operation */
	short		sem_flg;	/* operation flags */
};


#if	_KERNEL

/*
 * There is one linked list of undo structures per process.
 */

typedef	struct sem_undo	__sem_undo_t;

struct sem_undo {
	__sem_undo_t  *	un_np;		/* ptr to next active undo structure */
	short		un_aoe;		/* adjust on exit values */
	short		un_num;		/* semaphore # */
	int		un_id;		/* semid */
};

#endif	/* _KERNEL */

__EXTERN_C_BEGIN__

int		semctl		__PROTO ((int _semid, int _semnum, int _cmd,
					  ...));
int		semget		__PROTO ((__key_t _key, int _nsems,
					  int _semflg));
int		semop		__PROTO ((int _semid, struct sembuf * _sops,
					  __size_t _nsemops));

__EXTERN_C_END__

#endif /* ! defined (__SYS_SEM_H__) */