1/* $OpenBSD: msg.h,v 1.21 2024/04/30 17:03:05 op Exp $ */ 2/* $NetBSD: msg.h,v 1.9 1996/02/09 18:25:18 christos 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/ipc.h> 27 28/* 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. 31 */ 32 33#define MSG_NOERROR 010000 /* don't complain about too long msgs */ 34 35typedef unsigned long msgqnum_t; 36typedef unsigned long msglen_t; 37 38struct msqid_ds { 39 struct ipc_perm msg_perm; /* msg queue permission bits */ 40 struct msg *msg_first; /* first message in the queue */ 41 struct msg *msg_last; /* last message in the queue */ 42 msglen_t msg_cbytes; /* number of bytes in use on the queue */ 43 msgqnum_t msg_qnum; /* number of msgs in the queue */ 44 msglen_t msg_qbytes; /* max # of bytes on the queue */ 45 pid_t msg_lspid; /* pid of last msgsnd() */ 46 pid_t msg_lrpid; /* pid of last msgrcv() */ 47 time_t msg_stime; /* time of last msgsnd() */ 48 long msg_pad1; 49 time_t msg_rtime; /* time of last msgrcv() */ 50 long msg_pad2; 51 time_t msg_ctime; /* time of last msgctl() */ 52 long msg_pad3; 53 long msg_pad4[4]; 54}; 55 56#ifdef _KERNEL 57#include <sys/queue.h> 58 59struct msg { 60 long msg_type; 61 size_t msg_len; 62 struct mbuf *msg_data; 63 64 TAILQ_ENTRY(msg) msg_next; 65}; 66 67struct que { 68 struct msqid_ds msqid_ds; 69 int que_ix; /* pseudo-index */ 70 int que_flags; 71 int que_references; 72 73 TAILQ_ENTRY(que) que_next; 74 TAILQ_HEAD(, msg) que_msgs; 75}; 76 77/* for que_flags */ 78#define MSGQ_READERS 0x01 79#define MSGQ_WRITERS 0x02 80#define MSGQ_DYING 0x04 81 82#define QREF(q) (q)->que_references++ 83 84#define QRELE(q) do { \ 85 if (--(q)->que_references == 0 && (q)->que_flags & MSGQ_DYING) \ 86 wakeup_one(&(q)->que_references); \ 87} while (0) 88#endif 89 90/* 91 * Structure describing a message. The SVID doesn't suggest any 92 * particular name for this structure. There is a reference in the 93 * msgop man page that reads "The structure mymsg is an example of what 94 * this user defined buffer might look like, and includes the following 95 * members:". This sentence is followed by two lines equivalent 96 * to the mtype and mtext field declarations below. It isn't clear 97 * if "mymsg" refers to the name of the structure type or the name of an 98 * instance of the structure... 99 */ 100struct mymsg { 101 long mtype; /* message type (+ve integer) */ 102 char mtext[1]; /* message body */ 103}; 104 105 106#ifdef _KERNEL 107/* 108 * Based on the configuration parameters described in an SVR2 (yes, two) 109 * config(1m) man page. 110 * 111 * Each message is broken up and stored in segments that are msgssz bytes 112 * long. For efficiency reasons, this should be a power of two. Also, 113 * it doesn't make sense if it is less than 8 or greater than about 256. 114 * Consequently, msginit in kern/sysv_msg.c checks that msgssz is a power of 115 * two between 8 and 1024 inclusive (and panic's if it isn't). 116 */ 117struct msginfo { 118 int msgmax, /* max chars in a message */ 119 msgmni, /* max message queue identifiers */ 120 msgmnb, /* max chars in a queue */ 121 msgtql, /* max messages in system */ 122 msgssz, /* size of a message segment (see notes above) */ 123 msgseg; /* number of message segments */ 124}; 125#ifdef SYSVMSG 126extern struct msginfo msginfo; 127#endif 128 129int sysctl_sysvmsg(int *, u_int, void *, size_t *); 130 131struct msg_sysctl_info { 132 struct msginfo msginfo; 133 struct msqid_ds msgids[1]; 134}; 135 136#ifndef MSGSSZ 137#define MSGSSZ 8 /* Each segment must be 2^N long */ 138#endif 139#ifndef MSGSEG 140#define MSGSEG 2048 /* must be less than 32767 */ 141#endif 142#undef MSGMAX /* ALWAYS compute MSGMAX! */ 143#define MSGMAX (MSGSSZ*MSGSEG) 144#ifndef MSGMNB 145#define MSGMNB 2048 /* max # of bytes in a queue */ 146#endif 147#ifndef MSGMNI 148#define MSGMNI 40 149#endif 150#ifndef MSGTQL 151#define MSGTQL 40 152#endif 153 154/* 155 * macros to convert between msqid_ds's and msqid's. 156 * XXX unused, going away 157 */ 158#define MSQID(ix,ds) ((ix) & 0xffff | (((ds).msg_perm.seq << 16) & 0xffff0000)) 159#define MSQID_IX(id) ((id) & 0xffff) 160#define MSQID_SEQ(id) (((id) >> 16) & 0xffff) 161#endif 162 163 164#ifndef _KERNEL 165__BEGIN_DECLS 166int msgctl(int, int, struct msqid_ds *); 167int msgget(key_t, int); 168int msgsnd(int, const void *, size_t, int); 169int msgrcv(int, void *, size_t, long, int); 170__END_DECLS 171#else 172struct proc; 173 174void msginit(void); 175#endif /* !_KERNEL */ 176 177#endif /* !_SYS_MSG_H_ */ 178