1/* $FreeBSD: stable/11/sys/sys/msg.h 347995 2019-05-20 16:31:45Z kib $ */
2/*	$NetBSD: msg.h,v 1.4 1994/06/29 06:44:43 cgd Exp $	*/
3
4/*-
5 * SVID compatible msg.h file
6 *
7 * Author:  Daniel Boulet
8 *
9 * Copyright 1993 Daniel Boulet and RTMX Inc.
10 *
11 * This system call was implemented by Daniel Boulet under contract from RTMX.
12 *
13 * Redistribution and use in source forms, with and without modification,
14 * are permitted provided that this entire comment appears intact.
15 *
16 * Redistribution in binary form may occur without any restrictions.
17 * Obviously, it would be nice if you gave credit where credit is due
18 * but requiring it would be too onerous.
19 *
20 * This software is provided ``AS IS'' without any warranties of any kind.
21 */
22
23#ifndef _SYS_MSG_H_
24#define _SYS_MSG_H_
25
26#include <sys/cdefs.h>
27#include <sys/_types.h>
28#ifdef _WANT_SYSVMSG_INTERNALS
29#define	_WANT_SYSVIPC_INTERNALS
30#endif
31#include <sys/ipc.h>
32
33/*
34 * The MSG_NOERROR identifier value, the msqid_ds struct and the msg struct
35 * are as defined by the SV API Intel 386 Processor Supplement.
36 */
37
38#define MSG_NOERROR	010000		/* don't complain about too long msgs */
39
40typedef	unsigned long	msglen_t;
41typedef	unsigned long	msgqnum_t;
42
43#ifndef _PID_T_DECLARED
44typedef	__pid_t		pid_t;
45#define	_PID_T_DECLARED
46#endif
47
48#ifndef _SIZE_T_DECLARED
49typedef	__size_t	size_t;
50#define	_SIZE_T_DECLARED
51#endif
52
53#ifndef _SSIZE_T_DECLARED
54typedef	__ssize_t	ssize_t;
55#define	_SSIZE_T_DECLARED
56#endif
57
58#ifndef _TIME_T_DECLARED
59typedef	__time_t	time_t;
60#define	_TIME_T_DECLARED
61#endif
62
63#if defined(COMPAT_FREEBSD4) || defined(COMPAT_FREEBSD5) || \
64    defined(COMPAT_FREEBSD6) || defined(COMPAT_FREEBSD7)
65struct msqid_ds_old {
66	struct	ipc_perm_old msg_perm;	/* msg queue permission bits */
67	struct	msg *msg_first;	/* first message in the queue */
68	struct	msg *msg_last;	/* last message in the queue */
69	msglen_t msg_cbytes;	/* number of bytes in use on the queue */
70	msgqnum_t msg_qnum;	/* number of msgs in the queue */
71	msglen_t msg_qbytes;	/* max # of bytes on the queue */
72	pid_t	msg_lspid;	/* pid of last msgsnd() */
73	pid_t	msg_lrpid;	/* pid of last msgrcv() */
74	time_t	msg_stime;	/* time of last msgsnd() */
75	long	msg_pad1;
76	time_t	msg_rtime;	/* time of last msgrcv() */
77	long	msg_pad2;
78	time_t	msg_ctime;	/* time of last msgctl() */
79	long	msg_pad3;
80	long	msg_pad4[4];
81};
82#endif
83
84/*
85 * XXX there seems to be no prefix reserved for this header, so the name
86 * "msg" in "struct msg" and the names of all of the nonstandard members
87 * (mainly "msg_pad*) are namespace pollution.
88 */
89
90struct msqid_ds {
91	struct	ipc_perm msg_perm;	/* msg queue permission bits */
92	struct	msg *msg_first;	/* first message in the queue */
93	struct	msg *msg_last;	/* last message in the queue */
94	msglen_t msg_cbytes;	/* number of bytes in use on the queue */
95	msgqnum_t msg_qnum;	/* number of msgs in the queue */
96	msglen_t msg_qbytes;	/* max # of bytes on the queue */
97	pid_t	msg_lspid;	/* pid of last msgsnd() */
98	pid_t	msg_lrpid;	/* pid of last msgrcv() */
99	time_t	msg_stime;	/* time of last msgsnd() */
100	time_t	msg_rtime;	/* time of last msgrcv() */
101	time_t	msg_ctime;	/* time of last msgctl() */
102};
103
104#if __BSD_VISIBLE
105/*
106 * Structure describing a message.  The SVID doesn't suggest any
107 * particular name for this structure.  There is a reference in the
108 * msgop man page that reads "The structure mymsg is an example of what
109 * this user defined buffer might look like, and includes the following
110 * members:".  This sentence is followed by two lines equivalent
111 * to the mtype and mtext field declarations below.  It isn't clear
112 * if "mymsg" refers to the name of the structure type or the name of an
113 * instance of the structure...
114 */
115struct mymsg {
116	long	mtype;		/* message type (+ve integer) */
117	char	mtext[1];	/* message body */
118};
119#endif
120
121#ifdef _KERNEL
122struct msg {
123	struct	msg *msg_next;  /* next msg in the chain */
124	long	msg_type; 	/* type of this message */
125				/* >0 -> type of this message */
126				/* 0 -> free header */
127	u_short	msg_ts;		/* size of this message */
128	short	msg_spot;	/* location of start of msg in buffer */
129	struct	label *label;	/* MAC Framework label */
130};
131#endif
132
133#if defined(_KERNEL) || defined(_WANT_SYSVMSG_INTERNALS)
134/*
135 * Based on the configuration parameters described in an SVR2 (yes, two)
136 * config(1m) man page.
137 *
138 * Each message is broken up and stored in segments that are msgssz bytes
139 * long.  For efficiency reasons, this should be a power of two.  Also,
140 * it doesn't make sense if it is less than 8 or greater than about 256.
141 * Consequently, msginit in kern/sysv_msg.c checks that msgssz is a power of
142 * two between 8 and 1024 inclusive (and panic's if it isn't).
143 */
144struct msginfo {
145	int	msgmax,		/* max chars in a message */
146		msgmni,		/* max message queue identifiers */
147		msgmnb,		/* max chars in a queue */
148		msgtql,		/* max messages in system */
149		msgssz,		/* size of a message segment (see notes above) */
150		msgseg;		/* number of message segments */
151};
152
153/*
154 * Kernel wrapper for the user-level structure.
155 */
156struct msqid_kernel {
157	/*
158	 * Data structure exposed to user space.
159	 */
160	struct	msqid_ds u;
161
162	/*
163	 * Kernel-private components of the message queue.
164	 */
165	struct	label *label;	/* MAC label */
166	struct	ucred *cred;	/* creator's credentials */
167};
168#endif
169
170#ifdef _KERNEL
171extern struct msginfo	msginfo;
172
173#else /* _KERNEL */
174
175__BEGIN_DECLS
176int msgctl(int, int, struct msqid_ds *);
177int msgget(key_t, int);
178/* XXX return value should be ssize_t. */
179int msgrcv(int, void *, size_t, long, int);
180int msgsnd(int, const void *, size_t, int);
181#if __BSD_VISIBLE
182int msgsys(int, ...);
183#endif
184__END_DECLS
185#endif /* !_KERNEL */
186
187#endif /* !_SYS_MSG_H_ */
188