xref: /dragonfly/sys/sys/sem.h (revision 8accc937)
1 /* $FreeBSD: src/sys/sys/sem.h,v 1.20.2.2 2000/08/04 22:31:10 peter Exp $ */
2 /* $DragonFly: src/sys/sys/sem.h,v 1.4 2003/08/27 02:03:22 dillon Exp $ */
3 /*	$NetBSD: sem.h,v 1.5 1994/06/29 06:45:15 cgd Exp $	*/
4 
5 /*
6  * SVID compatible sem.h file
7  *
8  * Author:  Daniel Boulet
9  */
10 
11 #ifndef _SYS_SEM_H_
12 #define _SYS_SEM_H_
13 
14 #include <sys/ipc.h>
15 
16 struct sem;
17 
18 struct semid_ds {
19 	struct	ipc_perm sem_perm;	/* operation permission struct */
20 	struct	sem *sem_base;	/* pointer to first semaphore in set */
21 	u_short	sem_nsems;	/* number of sems in set */
22 	time_t	sem_otime;	/* last operation time */
23 	long	sem_pad1;	/* SVABI/386 says I need this here */
24 	time_t	sem_ctime;	/* last change time */
25     				/* Times measured in secs since */
26     				/* 00:00:00 GMT, Jan. 1, 1970 */
27 	long	sem_pad2;	/* SVABI/386 says I need this here */
28 	long	sem_pad3[4];	/* SVABI/386 says I need this here */
29 };
30 
31 #if defined(_KERNEL) || defined(_KERNEL_STRUCTURES)
32 
33 #include <sys/lock.h>
34 
35 struct semid_pool {
36 	struct lock lk;
37 	struct semid_ds ds;
38 	long gen;
39 };
40 
41 #endif
42 
43 /*
44  * semop's sops parameter structure
45  */
46 struct sembuf {
47 	u_short	sem_num;	/* semaphore # */
48 	short	sem_op;		/* semaphore operation */
49 	short	sem_flg;	/* operation flags */
50 };
51 #define SEM_UNDO	010000
52 
53 #define MAX_SOPS	5	/* maximum # of sembuf's per semop call */
54 
55 /*
56  * semctl's arg parameter structure
57  */
58 union semun {
59 	int	val;		/* value for SETVAL */
60 	struct	semid_ds *buf;	/* buffer for IPC_STAT & IPC_SET */
61 	u_short	*array;		/* array for GETALL & SETALL */
62 };
63 
64 /*
65  * commands for semctl
66  */
67 #define GETNCNT	3	/* Return the value of semncnt {READ} */
68 #define GETPID	4	/* Return the value of sempid {READ} */
69 #define GETVAL	5	/* Return the value of semval {READ} */
70 #define GETALL	6	/* Return semvals into arg.array {READ} */
71 #define GETZCNT	7	/* Return the value of semzcnt {READ} */
72 #define SETVAL	8	/* Set the value of semval to arg.val {ALTER} */
73 #define SETALL	9	/* Set semvals from arg.array {ALTER} */
74 #define SEM_STAT 10	/* Like IPC_STAT but treats semid as sema-index */
75 
76 /*
77  * Permissions
78  */
79 #define SEM_A		0200	/* alter permission */
80 #define SEM_R		0400	/* read permission */
81 
82 #if defined(_KERNEL) || defined(_KERNEL_STRUCTURES)
83 
84 /*
85  * semaphore info struct
86  */
87 struct seminfo {
88 	int	semmap,		/* # of entries in semaphore map */
89 		semmni,		/* # of semaphore identifiers */
90 		semmns,		/* # of semaphores in system */
91 		semmnu,		/* # of undo structures in system */
92 		semmsl,		/* max # of semaphores per id */
93 		semopm,		/* max # of operations per semop call */
94 		semume,		/* max # of undo entries per process */
95 		semusz,		/* size in bytes of undo structure */
96 		semvmx,		/* semaphore maximum value */
97 		semaem;		/* adjust on exit max value */
98 };
99 
100 /* internal "mode" bits */
101 #define	SEM_ALLOC	01000	/* semaphore is allocated */
102 #define	SEM_DEST	02000	/* semaphore will be destroyed on last detach */
103 
104 #endif /* _KERNEL || _KERNEL_STRUCTURES */
105 
106 #ifdef _KERNEL
107 
108 /*
109  * Process sem_undo vectors at proc exit.
110  */
111 void	semexit (struct proc *p);
112 extern struct seminfo	seminfo;
113 
114 #endif
115 
116 #ifndef _KERNEL
117 #include <sys/cdefs.h>
118 
119 __BEGIN_DECLS
120 int semsys (int, ...);
121 int semctl (int, int, int, ...);
122 int semget (key_t, int, int);
123 int semop (int, struct sembuf *,unsigned);
124 __END_DECLS
125 #endif /* !_KERNEL */
126 
127 #endif /* !_SEM_H_ */
128