freebsd-dev/sys/sys/sem.h
1999-08-28 01:08:13 +00:00

188 lines
4.8 KiB
C

/* $FreeBSD$ */
/* $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/ipc.h>
struct sem {
u_short semval; /* semaphore value */
pid_t sempid; /* pid of last operation */
u_short semncnt; /* # awaiting semval > cval */
u_short semzcnt; /* # awaiting semval = 0 */
};
struct semid_ds {
struct ipc_perm sem_perm; /* operation permission struct */
struct sem *sem_base; /* pointer to first semaphore in set */
u_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 */
};
/*
* semop's sops parameter structure
*/
struct sembuf {
u_short sem_num; /* semaphore # */
short sem_op; /* semaphore operation */
short sem_flg; /* operation flags */
};
#define SEM_UNDO 010000
#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 */
u_short *array; /* array for GETALL & SETALL */
};
/*
* 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} */
/*
* Permissions
*/
#define SEM_A 0200 /* alter permission */
#define SEM_R 0400 /* read permission */
#ifdef KERNEL
/*
* Kernel implementation stuff
*/
#define SEMVMX 32767 /* semaphore maximum value */
#define SEMAEM 16384 /* adjust on exit max value */
/*
* Undo structure (one per process)
*/
struct sem_undo {
struct sem_undo *un_next; /* ptr to next active undo structure */
struct proc *un_proc; /* owner of this structure */
short un_cnt; /* # of active entries */
struct undo {
short un_adjval; /* adjust on exit values */
short un_num; /* semaphore # */
int un_id; /* semid */
} un_ent[1]; /* undo entries */
};
/*
* 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 */
};
extern struct seminfo seminfo;
/* internal "mode" bits */
#define SEM_ALLOC 01000 /* semaphore is allocated */
#define SEM_DEST 02000 /* semaphore will be destroyed on last detach */
/*
* Configuration parameters
*/
#ifndef SEMMNI
#define SEMMNI 10 /* # of semaphore identifiers */
#endif
#ifndef SEMMNS
#define SEMMNS 60 /* # of semaphores in system */
#endif
#ifndef SEMUME
#define SEMUME 10 /* max # of undo entries per process */
#endif
#ifndef SEMMNU
#define SEMMNU 30 /* # of undo structures in system */
#endif
/* shouldn't need tuning */
#ifndef SEMMAP
#define SEMMAP 30 /* # of entries in semaphore map */
#endif
#ifndef SEMMSL
#define SEMMSL SEMMNS /* max # of semaphores per id */
#endif
#ifndef SEMOPM
#define SEMOPM 100 /* max # of operations per semop call */
#endif
/*
* Due to the way semaphore memory is allocated, we have to ensure that
* SEMUSZ is properly aligned.
*/
#define SEM_ALIGN(bytes) (((bytes) + (sizeof(long) - 1)) & ~(sizeof(long) - 1))
/* actual size of an undo structure */
#define SEMUSZ SEM_ALIGN(offsetof(struct sem_undo, un_ent[SEMUME]))
extern struct semid_ds *sema; /* semaphore id pool */
extern struct sem *sem; /* semaphore pool */
extern int *semu; /* undo structure pool */
/*
* Macro to find a particular sem_undo vector
*/
#define SEMU(ix) ((struct sem_undo *)(((intptr_t)semu)+ix * seminfo.semusz))
/*
* Process sem_undo vectors at proc exit.
*/
void semexit __P((struct proc *p));
/*
* Parameters to the semconfig system call
*/
typedef enum {
SEM_CONFIG_FREEZE, /* Freeze the semaphore facility. */
SEM_CONFIG_THAW /* Thaw the semaphore facility. */
} semconfig_ctl_t;
#endif /* KERNEL */
#ifndef KERNEL
#include <sys/cdefs.h>
__BEGIN_DECLS
int semsys __P((int, ...));
int semctl __P((int, int, int, ...));
int semget __P((key_t, int, int));
int semop __P((int, struct sembuf *,unsigned));
__END_DECLS
#endif /* !KERNEL */
#endif /* !_SEM_H_ */