1 /* $FreeBSD: src/sys/sys/msg.h,v 1.10.2.1 2000/08/04 22:31:10 peter Exp $ */ 2 /* $DragonFly: src/sys/sys/msg.h,v 1.4 2003/08/27 02:03:22 dillon Exp $ */ 3 /* $NetBSD: msg.h,v 1.4 1994/06/29 06:44:43 cgd Exp $ */ 4 5 /* 6 * SVID compatible msg.h file 7 * 8 * Author: Daniel Boulet 9 * 10 * Copyright 1993 Daniel Boulet and RTMX Inc. 11 * 12 * This system call was implemented by Daniel Boulet under contract from RTMX. 13 * 14 * Redistribution and use in source forms, with and without modification, 15 * are permitted provided that this entire comment appears intact. 16 * 17 * Redistribution in binary form may occur without any restrictions. 18 * Obviously, it would be nice if you gave credit where credit is due 19 * but requiring it would be too onerous. 20 * 21 * This software is provided ``AS IS'' without any warranties of any kind. 22 */ 23 24 #ifndef _SYS_MSG_H_ 25 #define _SYS_MSG_H_ 26 27 #include <sys/ipc.h> 28 29 /* 30 * The MSG_NOERROR identifier value, the msqid_ds struct and the msg struct 31 * are as defined by the SV API Intel 386 Processor Supplement. 32 */ 33 34 #define MSG_NOERROR 010000 /* don't complain about too long msgs */ 35 36 /*!!! In the kernel implementation, both msg_first and msg_last 37 * have 'struct msg*' type. 38 * In the userland implementation, a pointer to a msg is useless 39 * because each message queue is mapped at different addresses in 40 * the process space address so my choice was to use indexes. 41 */ 42 struct msg; 43 44 struct msqid_ds { 45 struct ipc_perm msg_perm; /* msg queue permission bits */ 46 struct msg *msg_first; /* first message in the queue. */ 47 struct msg *msg_last; /* last message in the queue. */ 48 u_long msg_cbytes; /* number of bytes in use on the queue */ 49 u_long msg_qnum; /* number of msgs in the queue */ 50 u_long msg_qbytes; /* max # of bytes on the queue */ 51 pid_t msg_lspid; /* pid of last msgsnd() */ 52 pid_t msg_lrpid; /* pid of last msgrcv() */ 53 time_t msg_stime; /* time of last msgsnd() */ 54 long msg_pad1; 55 time_t msg_rtime; /* time of last msgrcv() */ 56 long msg_pad2; 57 time_t msg_ctime; /* time of last msgctl() */ 58 long msg_pad3; 59 long msg_pad4[4]; 60 }; 61 62 /* 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... 71 */ 72 struct mymsg { 73 long mtype; /* message type (+ve integer) */ 74 char mtext[1]; /* message body */ 75 }; 76 77 #if defined(_KERNEL) || defined(_KERNEL_STRUCTURES) 78 79 /* 80 * Based on the configuration parameters described in an SVR2 (yes, two) 81 * config(1m) man page. 82 * 83 * Each message is broken up and stored in segments that are msgssz bytes 84 * long. For efficiency reasons, this should be a power of two. Also, 85 * it doesn't make sense if it is less than 8 or greater than about 256. 86 * Consequently, msginit in kern/sysv_msg.c checks that msgssz is a power of 87 * two between 8 and 1024 inclusive (and panic's if it isn't). 88 */ 89 struct msginfo { 90 int msgmax, /* max chars in a message */ 91 msgmni, /* max message queue identifiers */ 92 msgmnb, /* max chars in a queue */ 93 msgtql, /* max messages in system */ 94 msgssz, /* size of a message segment (see notes above) */ 95 msgseg; /* number of message segments */ 96 }; 97 #endif 98 99 #ifdef _KERNEL 100 extern struct msginfo msginfo; 101 #endif 102 103 #ifndef _KERNEL 104 105 #include <sys/cdefs.h> 106 107 __BEGIN_DECLS 108 int msgsys (int, ...); 109 int msgctl (int, int, struct msqid_ds *); 110 int msgget (key_t, int); 111 int msgsnd (int, void *, size_t, int); 112 int msgrcv (int, void*, size_t, long, int); 113 __END_DECLS 114 #endif 115 116 #endif /* !_SYS_MSG_H_ */ 117