/* $FreeBSD: src/sys/sys/sem.h,v 1.20.2.2 2000/08/04 22:31:10 peter Exp $ */
/*      $NetBSD: sem.h,v 1.5 1994/06/29 06:45:15 cgd Exp $      */

/*
 * SVID compatible sem.h file
 *
 * Author:  Daniel Boulet
 */

#ifndef _SYS_SEM_H_
#define _SYS_SEM_H_

#include <sys/cdefs.h>
#include <sys/ipc.h>
#include <machine/stdint.h>

#ifndef _PID_T_DECLARED
typedef __pid_t         pid_t;
#define _PID_T_DECLARED
#endif

#ifndef _SIZE_T_DECLARED
typedef __size_t        size_t;
#define _SIZE_T_DECLARED
#endif

#ifndef _TIME_T_DECLARED
typedef __time_t        time_t;
#define _TIME_T_DECLARED
#endif

struct sem;

struct semid_ds {
        struct  ipc_perm sem_perm;      /* operation permission struct */
        struct  sem *sem_base;  /* pointer to first semaphore in set */
        unsigned short sem_nsems;       /* number of sems in set */
        time_t  sem_otime;      /* last operation time */
        long    sem_pad1;       /* SVABI/386 says I need this here */
        time_t  sem_ctime;      /* last change time */
                                /* Times measured in secs since */
                                /* 00:00:00 GMT, Jan. 1, 1970 */
        long    sem_pad2;       /* SVABI/386 says I need this here */
        long    sem_pad3[4];    /* SVABI/386 says I need this here */
};

#if defined(_KERNEL) || defined(_KERNEL_STRUCTURES)

#include <sys/lock.h>

struct semid_pool {
        struct lock lk;
        struct semid_ds ds;
        long gen;
};

#endif

/*
 * semop's sops parameter structure
 */
struct sembuf {
        unsigned short sem_num; /* semaphore # */
        short   sem_op;         /* semaphore operation */
        short   sem_flg;        /* operation flags */
};
#define SEM_UNDO        010000

#if __BSD_VISIBLE
#define MAX_SOPS        5       /* maximum # of sembuf's per semop call */

/*
 * semctl's arg parameter structure
 */
union semun {
        int     val;            /* value for SETVAL */
        struct  semid_ds *buf;  /* buffer for IPC_STAT & IPC_SET */
        unsigned short  *array; /* array for GETALL & SETALL */
};
#endif /* __BSD_VISIBLE */

/*
 * commands for semctl
 */
#define GETNCNT 3       /* Return the value of semncnt {READ} */
#define GETPID  4       /* Return the value of sempid {READ} */
#define GETVAL  5       /* Return the value of semval {READ} */
#define GETALL  6       /* Return semvals into arg.array {READ} */
#define GETZCNT 7       /* Return the value of semzcnt {READ} */
#define SETVAL  8       /* Set the value of semval to arg.val {ALTER} */
#define SETALL  9       /* Set semvals from arg.array {ALTER} */
#if __BSD_VISIBLE
#define SEM_STAT 10     /* Like IPC_STAT but treats semid as sema-index */

/*
 * Permissions
 */
#define SEM_A           0200    /* alter permission */
#define SEM_R           0400    /* read permission */
#endif /* __BSD_VISIBLE */

#if defined(_KERNEL) || defined(_KERNEL_STRUCTURES)

/*
 * semaphore info struct
 */
struct seminfo {
        int     semmap,         /* # of entries in semaphore map */
                semmni,         /* # of semaphore identifiers */
                semmns,         /* # of semaphores in system */
                semmnu,         /* # of undo structures in system */
                semmsl,         /* max # of semaphores per id */
                semopm,         /* max # of operations per semop call */
                semume,         /* max # of undo entries per process */
                semusz,         /* size in bytes of undo structure */
                semvmx,         /* semaphore maximum value */
                semaem;         /* adjust on exit max value */
};

/* internal "mode" bits */
#define SEM_ALLOC       01000   /* semaphore is allocated */
#define SEM_DEST        02000   /* semaphore will be destroyed on last detach */

#endif /* _KERNEL || _KERNEL_STRUCTURES */

#ifdef _KERNEL
/*
 * Process sem_undo vectors at proc exit.
 */
void    semexit(struct proc *p);
extern struct seminfo   seminfo;
#else
__BEGIN_DECLS
int     semctl(int, int, int, ...);
int     semget(key_t, int, int);
int     semop(int, struct sembuf *, unsigned);
__END_DECLS
#endif /* !_KERNEL */

#endif /* !_SEM_H_ */