shm.h revision 50477 
1/* $FreeBSD: head/sys/sys/shm.h 50477 1999-08-28 01:08:13Z peter $ */
2/*	$NetBSD: shm.h,v 1.15 1994/06/29 06:45:17 cgd Exp $	*/
3
4/*
5 * Copyright (c) 1994 Adam Glass
6 * All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 *    notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 *    notice, this list of conditions and the following disclaimer in the
15 *    documentation and/or other materials provided with the distribution.
16 * 3. All advertising materials mentioning features or use of this software
17 *    must display the following acknowledgement:
18 *      This product includes software developed by Adam Glass.
19 * 4. The name of the author may not be used to endorse or promote products
20 *    derived from this software without specific prior written permission
21 *
22 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
23 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
24 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
25 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
26 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
27 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
28 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
29 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
30 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
31 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32 */
33
34/*
35 * As defined+described in "X/Open System Interfaces and Headers"
36 *                         Issue 4, p. XXX
37 */
38
39#ifndef _SYS_SHM_H_
40#define _SYS_SHM_H_
41
42#include <sys/ipc.h>
43
44#define SHM_RDONLY  010000  /* Attach read-only (else read-write) */
45#define SHM_RND     020000  /* Round attach address to SHMLBA */
46#define SHMLBA      PAGE_SIZE /* Segment low boundary address multiple */
47
48/* "official" access mode definitions; somewhat braindead since you have
49   to specify (SHM_* >> 3) for group and (SHM_* >> 6) for world permissions */
50#define SHM_R       (IPC_R)
51#define SHM_W       (IPC_W)
52
53
54struct shmid_ds {
55	struct ipc_perm shm_perm;	/* operation permission structure */
56	int             shm_segsz;	/* size of segment in bytes */
57	pid_t           shm_lpid;   /* process ID of last shared memory op */
58	pid_t           shm_cpid;	/* process ID of creator */
59	short		shm_nattch;	/* number of current attaches */
60	time_t          shm_atime;	/* time of last shmat() */
61	time_t          shm_dtime;	/* time of last shmdt() */
62	time_t          shm_ctime;	/* time of last change by shmctl() */
63	void           *shm_internal;   /* sysv stupidity */
64};
65
66#ifdef KERNEL
67
68/*
69 * System 5 style catch-all structure for shared memory constants that
70 * might be of interest to user programs.  Do we really want/need this?
71 */
72struct shminfo {
73	int	shmmax,		/* max shared memory segment size (bytes) */
74		shmmin,		/* min shared memory segment size (bytes) */
75		shmmni,		/* max number of shared memory identifiers */
76		shmseg,		/* max shared memory segments per process */
77		shmall;		/* max amount of shared memory (pages) */
78};
79extern struct shminfo	shminfo;
80extern struct shmid_ds	*shmsegs;
81
82struct proc;
83
84void	shmexit __P((struct proc *));
85void	shmfork __P((struct proc *, struct proc *));
86#else /* !KERNEL */
87
88#include <sys/cdefs.h>
89
90__BEGIN_DECLS
91int shmsys __P((int, ...));
92void *shmat  __P((int, void *, int));
93int shmget __P((key_t, int, int));
94int shmctl __P((int, int, struct shmid_ds *));
95int shmdt  __P((void *));
96__END_DECLS
97
98#endif /* !KERNEL */
99
100#endif /* !_SYS_SHM_H_ */
101