/
msg.h
158 lines (138 loc) · 4.75 KB
/
msg.h
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
/* $Id: msg.h,v 1.8 1997/02/22 09:45:36 peter Exp $ */
/* $NetBSD: msg.h,v 1.4 1994/06/29 06:44:43 cgd Exp $ */
/*
* SVID compatible msg.h file
*
* Author: Daniel Boulet
*
* Copyright 1993 Daniel Boulet and RTMX Inc.
*
* This system call was implemented by Daniel Boulet under contract from RTMX.
*
* Redistribution and use in source forms, with and without modification,
* are permitted provided that this entire comment appears intact.
*
* Redistribution in binary form may occur without any restrictions.
* Obviously, it would be nice if you gave credit where credit is due
* but requiring it would be too onerous.
*
* This software is provided ``AS IS'' without any warranties of any kind.
*/
#ifndef _SYS_MSG_H_
#define _SYS_MSG_H_
#include <sys/ipc.h>
/*
* The MSG_NOERROR identifier value, the msqid_ds struct and the msg struct
* are as defined by the SV API Intel 386 Processor Supplement.
*/
#define MSG_NOERROR 010000 /* don't complain about too long msgs */
struct msqid_ds {
struct ipc_perm msg_perm; /* msg queue permission bits */
struct msg *msg_first; /* first message in the queue */
struct msg *msg_last; /* last message in the queue */
u_long msg_cbytes; /* number of bytes in use on the queue */
u_long msg_qnum; /* number of msgs in the queue */
u_long msg_qbytes; /* max # of bytes on the queue */
pid_t msg_lspid; /* pid of last msgsnd() */
pid_t msg_lrpid; /* pid of last msgrcv() */
time_t msg_stime; /* time of last msgsnd() */
long msg_pad1;
time_t msg_rtime; /* time of last msgrcv() */
long msg_pad2;
time_t msg_ctime; /* time of last msgctl() */
long msg_pad3;
long msg_pad4[4];
};
struct msg {
struct msg *msg_next; /* next msg in the chain */
long msg_type; /* type of this message */
/* >0 -> type of this message */
/* 0 -> free header */
u_short msg_ts; /* size of this message */
short msg_spot; /* location of start of msg in buffer */
};
/*
* Structure describing a message. The SVID doesn't suggest any
* particular name for this structure. There is a reference in the
* msgop man page that reads "The structure mymsg is an example of what
* this user defined buffer might look like, and includes the following
* members:". This sentence is followed by two lines equivalent
* to the mtype and mtext field declarations below. It isn't clear
* if "mymsg" refers to the naem of the structure type or the name of an
* instance of the structure...
*/
struct mymsg {
long mtype; /* message type (+ve integer) */
char mtext[1]; /* message body */
};
/*
* Based on the configuration parameters described in an SVR2 (yes, two)
* config(1m) man page.
*
* Each message is broken up and stored in segments that are msgssz bytes
* long. For efficiency reasons, this should be a power of two. Also,
* it doesn't make sense if it is less than 8 or greater than about 256.
* Consequently, msginit in kern/sysv_msg.c checks that msgssz is a power of
* two between 8 and 1024 inclusive (and panic's if it isn't).
*/
struct msginfo {
int msgmax, /* max chars in a message */
msgmni, /* max message queue identifiers */
msgmnb, /* max chars in a queue */
msgtql, /* max messages in system */
msgssz, /* size of a message segment (see notes above) */
msgseg; /* number of message segments */
};
#ifdef KERNEL
extern struct msginfo msginfo;
#ifndef MSGSSZ
#define MSGSSZ 8 /* Each segment must be 2^N long */
#endif
#ifndef MSGSEG
#define MSGSEG 2048 /* must be less than 32767 */
#endif
#define MSGMAX (MSGSSZ*MSGSEG)
#ifndef MSGMNB
#define MSGMNB 2048 /* max # of bytes in a queue */
#endif
#ifndef MSGMNI
#define MSGMNI 40
#endif
#ifndef MSGTQL
#define MSGTQL 40
#endif
/*
* macros to convert between msqid_ds's and msqid's.
* (specific to this implementation)
*/
#define MSQID(ix,ds) ((ix) & 0xffff | (((ds).msg_perm.seq << 16) & 0xffff0000))
#define MSQID_IX(id) ((id) & 0xffff)
#define MSQID_SEQ(id) (((id) >> 16) & 0xffff)
/*
* The rest of this file is specific to this particular implementation.
*/
/*
* Stuff allocated in machdep.h
*/
struct msgmap {
short next; /* next segment in buffer */
/* -1 -> available */
/* 0..(MSGSEG-1) -> index of next segment */
};
extern char *msgpool; /* MSGMAX byte long msg buffer pool */
extern struct msgmap *msgmaps; /* MSGSEG msgmap structures */
extern struct msg *msghdrs; /* MSGTQL msg headers */
extern struct msqid_ds *msqids; /* MSGMNI msqid_ds struct's */
#define MSG_LOCKED 01000 /* Is this msqid_ds locked? */
#endif /* KERNEL */
#ifndef KERNEL
#include <sys/cdefs.h>
__BEGIN_DECLS
int msgsys __P((int, ...));
int msgctl __P((int, int, struct msqid_ds *));
int msgget __P((key_t, int));
int msgsnd __P((int, void *, size_t, int));
int msgrcv __P((int, void*, size_t, long, int));
__END_DECLS
#endif /* !KERNEL */
#endif /* !_SYS_MSG_H_ */