2 /* $NetBSD: msg.h,v 1.4 1994/06/29 06:44:43 cgd Exp $ */
5 * SVID compatible msg.h file
7 * Author: Daniel Boulet
9 * Copyright 1993 Daniel Boulet and RTMX Inc.
11 * This system call was implemented by Daniel Boulet under contract from RTMX.
13 * Redistribution and use in source forms, with and without modification,
14 * are permitted provided that this entire comment appears intact.
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.
20 * This software is provided ``AS IS'' without any warranties of any kind.
29 * The MSG_NOERROR identifier value, the msqid_ds struct and the msg struct
30 * are as defined by the SV API Intel 386 Processor Supplement.
33 #define MSG_NOERROR 010000 /* don't complain about too long msgs */
36 struct ipc_perm msg_perm; /* msg queue permission bits */
37 struct msg *msg_first; /* first message in the queue */
38 struct msg *msg_last; /* last message in the queue */
39 u_long msg_cbytes; /* number of bytes in use on the queue */
40 u_long msg_qnum; /* number of msgs in the queue */
41 u_long msg_qbytes; /* max # of bytes on the queue */
42 pid_t msg_lspid; /* pid of last msgsnd() */
43 pid_t msg_lrpid; /* pid of last msgrcv() */
44 time_t msg_stime; /* time of last msgsnd() */
46 time_t msg_rtime; /* time of last msgrcv() */
48 time_t msg_ctime; /* time of last msgctl() */
54 struct msg *msg_next; /* next msg in the chain */
55 long msg_type; /* type of this message */
56 /* >0 -> type of this message */
57 /* 0 -> free header */
58 u_short msg_ts; /* size of this message */
59 short msg_spot; /* location of start of msg in buffer */
63 * Structure describing a message. The SVID doesn't suggest any
64 * particular name for this structure. There is a reference in the
65 * msgop man page that reads "The structure mymsg is an example of what
66 * this user defined buffer might look like, and includes the following
67 * members:". This sentence is followed by two lines equivalent
68 * to the mtype and mtext field declarations below. It isn't clear
69 * if "mymsg" refers to the naem of the structure type or the name of an
70 * instance of the structure...
73 long mtype; /* message type (+ve integer) */
74 char mtext[1]; /* message body */
78 * Based on the configuration parameters described in an SVR2 (yes, two)
79 * config(1m) man page.
81 * Each message is broken up and stored in segments that are msgssz bytes
82 * long. For efficiency reasons, this should be a power of two. Also,
83 * it doesn't make sense if it is less than 8 or greater than about 256.
84 * Consequently, msginit in kern/sysv_msg.c checks that msgssz is a power of
85 * two between 8 and 1024 inclusive (and panic's if it isn't).
88 int msgmax, /* max chars in a message */
89 msgmni, /* max message queue identifiers */
90 msgmnb, /* max chars in a queue */
91 msgtql, /* max messages in system */
92 msgssz, /* size of a message segment (see notes above) */
93 msgseg; /* number of message segments */
96 extern struct msginfo msginfo;
99 #define MSGSSZ 8 /* Each segment must be 2^N long */
102 #define MSGSEG 2048 /* must be less than 32767 */
104 #define MSGMAX (MSGSSZ*MSGSEG)
106 #define MSGMNB 2048 /* max # of bytes in a queue */
116 * macros to convert between msqid_ds's and msqid's.
117 * (specific to this implementation)
119 #define MSQID(ix,ds) ((ix) & 0xffff | (((ds).msg_perm.seq << 16) & 0xffff0000))
120 #define MSQID_IX(id) ((id) & 0xffff)
121 #define MSQID_SEQ(id) (((id) >> 16) & 0xffff)
124 * The rest of this file is specific to this particular implementation.
129 * Stuff allocated in machdep.h
132 short next; /* next segment in buffer */
133 /* -1 -> available */
134 /* 0..(MSGSEG-1) -> index of next segment */
137 extern char *msgpool; /* MSGMAX byte long msg buffer pool */
138 extern struct msgmap *msgmaps; /* MSGSEG msgmap structures */
139 extern struct msg *msghdrs; /* MSGTQL msg headers */
140 extern struct msqid_ds *msqids; /* MSGMNI msqid_ds struct's */
142 #define MSG_LOCKED 01000 /* Is this msqid_ds locked? */
147 #include <sys/cdefs.h>
150 int msgsys __P((int, ...));
151 int msgctl __P((int, int, struct msqid_ds *));
152 int msgget __P((key_t, int));
153 int msgsnd __P((int, void *, size_t, int));
154 int msgrcv __P((int, void*, size_t, long, int));
158 #endif /* !_SYS_MSG_H_ */