bsd/sys/msg.h

   1 /*
   2  * Copyright (c) 2000-2005 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * The contents of this file constitute Original Code as defined in and
   7  * are subject to the Apple Public Source License Version 1.1 (the
   8  * "License").  You may not use this file except in compliance with the
   9  * License.  Please obtain a copy of the License at
  10  * http://www.apple.com/publicsource and read it before using this file.
  11  *
  12  * This Original Code and all software distributed under the License are
  13  * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  14  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  15  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  16  * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
  17  * License for the specific language governing rights and limitations
  18  * under the License.
  19  *
  20  * @APPLE_LICENSE_HEADER_END@
  21  */
  22 /*      $NetBSD: msg.h,v 1.4 1994/06/29 06:44:43 cgd Exp $      */
  23
  24 /*
  25  * SVID compatible msg.h file
  26  *
  27  * Author:  Daniel Boulet
  28  *
  29  * Copyright 1993 Daniel Boulet and RTMX Inc.
  30  *
  31  * This system call was implemented by Daniel Boulet under contract from RTMX.
  32  *
  33  * Redistribution and use in source forms, with and without modification,
  34  * are permitted provided that this entire comment appears intact.
  35  *
  36  * Redistribution in binary form may occur without any restrictions.
  37  * Obviously, it would be nice if you gave credit where credit is due
  38  * but requiring it would be too onerous.
  39  *
  40  * This software is provided ``AS IS'' without any warranties of any kind.
  41  */
  42
  43 #ifndef _SYS_MSG_H_
  44 #define _SYS_MSG_H_
  45
  46 #include <sys/appleapiopts.h>
  47
  48 #include <sys/_types.h>
  49 #include <sys/cdefs.h>
  50
  51 /*
  52  * [XSI] All of the symbols from <sys/ipc.h> SHALL be defined when this
  53  * header is included
  54  */
  55 #include <sys/ipc.h>
  56
  57
  58 /*
  59  * [XSI] The pid_t, time_t, key_t, size_t, and ssize_t types shall be
  60  * defined as described in <sys/types.h>.
  61  *
  62  * NOTE:        The definition of the key_t type is implicit from the
  63  *              inclusion of <sys/ipc.h>
  64  */
  65 #ifndef _PID_T
  66 typedef __darwin_pid_t          pid_t;
  67 #define _PID_T
  68 #endif
  69
  70 #ifndef _TIME_T
  71 #define _TIME_T
  72 typedef __darwin_time_t         time_t;
  73 #endif
  74
  75 #ifndef _SIZE_T
  76 #define _SIZE_T
  77 typedef __darwin_size_t         size_t;
  78 #endif
  79
  80 #ifndef _SSIZE_T
  81 #define _SSIZE_T
  82 typedef __darwin_ssize_t        ssize_t;
  83 #endif
  84
  85 /* [XSI] Used for the number of messages in the message queue */
  86 typedef unsigned long           msgqnum_t;
  87
  88 /* [XSI] Used for the number of bytes allowed in a message queue */
  89 typedef unsigned long           msglen_t;
  90
  91
  92 /*
  93  * Possible values for the fifth parameter to msgrcv(), in addition to the
  94  * IPC_NOWAIT flag, which is permitted.
  95  */
  96 #define MSG_NOERROR     010000          /* [XSI] No error if big message */
  97
  98
  99 /*
 100  * Technically, we should force all code references to the new structure
 101  * definition, not in just the standards conformance case, and leave the
 102  * legacy interface there for binary compatibility only.  Currently, we
 103  * are only forcing this for programs requesting standards conformance.
 104  */
 105 #if defined(__POSIX_C_SOURCE) || defined(kernel) || defined(__LP64__)
 106 /*
 107  * Structure used internally.
 108  *
 109  * Structure whose address is passed as the third parameter to msgctl()
 110  * when the second parameter is IPC_SET or IPC_STAT.  In the case of the
 111  * IPC_SET command, only the msg_perm.{uid|gid|perm} and msg_qbytes are
 112  * honored.  In the case of IPC_STAT, only the fields indicated as [XSI]
 113  * mandated fields are guaranteed to meaningful: DO NOT depend on the
 114  * contents of the other fields.
 115  *
 116  * NOTES:       Reserved fields are not preserved across IPC_SET/IPC_STAT.
 117  */
 118 struct __msqid_ds_new {
 119         struct __ipc_perm_new   msg_perm; /* [XSI] msg queue permissions */
 120         __int32_t       msg_first;      /* RESERVED: kernel use only */
 121         __int32_t       msg_last;       /* RESERVED: kernel use only */
 122         msglen_t        msg_cbytes;     /* # of bytes on the queue */
 123         msgqnum_t       msg_qnum;       /* [XSI] number of msgs on the queue */
 124         msglen_t        msg_qbytes;     /* [XSI] max bytes on the queue */
 125         pid_t           msg_lspid;      /* [XSI] pid of last msgsnd() */
 126         pid_t           msg_lrpid;      /* [XSI] pid of last msgrcv() */
 127         time_t          msg_stime;      /* [XSI] time of last msgsnd() */
 128         __int32_t       msg_pad1;       /* RESERVED: DO NOT USE */
 129         time_t          msg_rtime;      /* [XSI] time of last msgrcv() */
 130         __int32_t       msg_pad2;       /* RESERVED: DO NOT USE */
 131         time_t          msg_ctime;      /* [XSI] time of last msgctl() */
 132         __int32_t       msg_pad3;       /* RESERVED: DO NOT USE */
 133         __int32_t       msg_pad4[4];    /* RESERVED: DO NOT USE */
 134 };
 135 #define msqid_ds        __msqid_ds_new
 136 #else   /* !_POSIX_C_SOURCE */
 137 #define msqid_ds        __msqid_ds_old
 138 #endif  /* !_POSIX_C_SOURCE */
 139
 140 #if !defined(__POSIX_C_SOURCE) && !defined(__LP64__)
 141 struct __msqid_ds_old {
 142         struct __ipc_perm_old   msg_perm; /* [XSI] msg queue permissions */
 143         __int32_t       msg_first;      /* RESERVED: kernel use only */
 144         __int32_t       msg_last;       /* RESERVED: kernel use only */
 145         msglen_t        msg_cbytes;     /* # of bytes on the queue */
 146         msgqnum_t       msg_qnum;       /* [XSI] number of msgs on the queue */
 147         msglen_t        msg_qbytes;     /* [XSI] max bytes on the queue */
 148         pid_t           msg_lspid;      /* [XSI] pid of last msgsnd() */
 149         pid_t           msg_lrpid;      /* [XSI] pid of last msgrcv() */
 150         time_t          msg_stime;      /* [XSI] time of last msgsnd() */
 151         __int32_t       msg_pad1;       /* RESERVED: DO NOT USE */
 152         time_t          msg_rtime;      /* [XSI] time of last msgrcv() */
 153         __int32_t       msg_pad2;       /* RESERVED: DO NOT USE */
 154         time_t          msg_ctime;      /* [XSI] time of last msgctl() */
 155         __int32_t       msg_pad3;       /* RESERVED: DO NOT USE */
 156         __int32_t       msg_pad4[4];    /* RESERVED: DO NOT USE */
 157 };
 158 #endif  /* !_POSIX_C_SOURCE */
 159
 160 #ifdef KERNEL
 161 #ifdef __APPLE_API_PRIVATE
 162 #include <machine/types.h>
 163
 164 // LP64todo - should this move?
 165
 166 #if __DARWIN_ALIGN_NATURAL
 167 #pragma options align=natural
 168 #endif
 169
 170 struct user_msqid_ds {
 171         struct ipc_perm msg_perm;       /* [XSI] msg queue permissions */
 172         struct msg      *msg_first;     /* first message in the queue */
 173         struct msg      *msg_last;      /* last message in the queue */
 174         msglen_t        msg_cbytes;     /* # of bytes on the queue */
 175         msgqnum_t       msg_qnum;       /* [XSI] number of msgs on the queue */
 176         msglen_t        msg_qbytes;     /* [XSI] max bytes on the queue */
 177         pid_t           msg_lspid;      /* [XSI] pid of last msgsnd() */
 178         pid_t           msg_lrpid;      /* [XSI] pid of last msgrcv() */
 179         user_time_t     msg_stime;      /* [XSI] time of last msgsnd() */
 180         __int32_t       msg_pad1;       /* RESERVED: DO NOT USE */
 181         user_time_t     msg_rtime;      /* [XSI] time of last msgrcv() */
 182         __int32_t       msg_pad2;       /* RESERVED: DO NOT USE */
 183         user_time_t     msg_ctime;      /* [XSI] time of last msgctl() */
 184         __int32_t       msg_pad3;       /* RESERVED: DO NOT USE */
 185         __int32_t       msg_pad4[4];
 186 };
 187
 188 #if __DARWIN_ALIGN_NATURAL
 189 #pragma options align=reset
 190 #endif
 191
 192 #endif  /* __APPLE_API_PRIVATE */
 193 #endif  /* KERNEL */
 194
 195
 196 #ifndef _POSIX_C_SOURCE
 197 #ifdef __APPLE_API_UNSTABLE
 198 /* XXX kernel only; protect with macro later */
 199
 200 struct msg {
 201         struct msg      *msg_next;      /* next msg in the chain */
 202         long            msg_type;       /* type of this message */
 203                                         /* >0 -> type of this message */
 204                                         /* 0 -> free header */
 205         unsigned short  msg_ts;         /* size of this message */
 206         short           msg_spot;       /* location of msg start in buffer */
 207 };
 208
 209 /*
 210  * Example structure describing a message whose address is to be passed as
 211  * the second argument to the functions msgrcv() and msgsnd().  The only
 212  * actual hard requirement is that the first field be of type long, and
 213  * contain the message type.  The user is encouraged to define their own
 214  * application specific structure; this definition is included solely for
 215  * backward compatability with existing source code.
 216  */
 217 struct mymsg {
 218         long    mtype;          /* message type (+ve integer) */
 219         char    mtext[1];       /* message body */
 220 };
 221
 222 /*
 223  * Based on the configuration parameters described in an SVR2 (yes, two)
 224  * config(1m) man page.
 225  *
 226  * Each message is broken up and stored in segments that are msgssz bytes
 227  * long.  For efficiency reasons, this should be a power of two.  Also,
 228  * it doesn't make sense if it is less than 8 or greater than about 256.
 229  * Consequently, msginit in kern/sysv_msg.c checks that msgssz is a power of
 230  * two between 8 and 1024 inclusive (and panic's if it isn't).
 231  */
 232 struct msginfo {
 233         int     msgmax,         /* max chars in a message */
 234                 msgmni,         /* max message queue identifiers */
 235                 msgmnb,         /* max chars in a queue */
 236                 msgtql,         /* max messages in system */
 237                 msgssz,         /* size of a message segment (see notes above) */
 238                 msgseg;         /* number of message segments */
 239 };
 240 #ifdef KERNEL
 241 extern struct msginfo   msginfo;
 242
 243 #ifndef MSGSSZ
 244 #define MSGSSZ  8               /* Each segment must be 2^N long */
 245 #endif
 246 #ifndef MSGSEG
 247 #define MSGSEG  2048            /* must be less than 32767 */
 248 #endif
 249 #define MSGMAX  (MSGSSZ*MSGSEG)
 250 #ifndef MSGMNB
 251 #define MSGMNB  2048            /* max # of bytes in a queue */
 252 #endif
 253 #ifndef MSGMNI
 254 #define MSGMNI  40
 255 #endif
 256 #ifndef MSGTQL
 257 #define MSGTQL  40
 258 #endif
 259
 260 /*
 261  * macros to convert between msqid_ds's and msqid's.
 262  * (specific to this implementation)
 263  */
 264 #define MSQID(ix,ds)    ((ix) & 0xffff | (((ds).msg_perm.seq << 16) & 0xffff0000))
 265 #define MSQID_IX(id)    ((id) & 0xffff)
 266 #define MSQID_SEQ(id)   (((id) >> 16) & 0xffff)
 267
 268 /*
 269  * The rest of this file is specific to this particular implementation.
 270  */
 271
 272
 273 /*
 274  * Stuff allocated in machdep.h
 275  */
 276 struct msgmap {
 277         short   next;           /* next segment in buffer */
 278                                 /* -1 -> available */
 279                                 /* 0..(MSGSEG-1) -> index of next segment */
 280 };
 281
 282 /* The following four externs really, really need to die; should be static */
 283 extern char *msgpool;           /* MSGMAX byte long msg buffer pool */
 284 extern struct msgmap *msgmaps;  /* MSGSEG msgmap structures */
 285 extern struct msg *msghdrs;     /* MSGTQL msg headers */
 286 extern struct user_msqid_ds     *msqids; /* MSGMNI user_msqid_ds struct's */
 287
 288 #define MSG_LOCKED      01000   /* Is this msqid_ds locked? */
 289
 290 #endif  /* KERNEL */
 291 #endif  /* __APPLE_API_UNSTABLE */
 292 #endif  /* !_POSIX_C_SOURCE */
 293
 294 #ifndef KERNEL
 295
 296 __BEGIN_DECLS
 297 #ifndef _POSIX_C_SOURCE
 298 int msgsys(int, ...);
 299 #endif  /* !_POSIX_C_SOURCE */
 300 int msgctl(int, int, struct msqid_ds *) __DARWIN_ALIAS(msgctl);
 301 int msgget(key_t, int);
 302 ssize_t msgrcv(int, void *, size_t, long, int);
 303 int msgsnd(int, const void *, size_t, int);
 304 __END_DECLS
 305
 306 #endif /* !KERNEL */
 307
 308 #endif /* !_SYS_MSG_H_ */