bsd/sys/msg.h

   1 /*
   2  * Copyright (c) 2000-2007 Apple Inc. All rights reserved.
   3  *
   4  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
   7  * as defined in and that are subject to the Apple Public Source License
   8  * Version 2.0 (the 'License'). You may not use this file except in
   9  * compliance with the License. The rights granted to you under the License
  10  * may not be used to create, or enable the creation or redistribution of,
  11  * unlawful or unlicensed copies of an Apple operating system, or to
  12  * circumvent, violate, or enable the circumvention or violation of, any
  13  * terms of an Apple operating system software license agreement.
  14  *
  15  * Please obtain a copy of the License at
  16  * http://www.opensource.apple.com/apsl/ and read it before using this file.
  17  *
  18  * The Original Code and all software distributed under the License are
  19  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  20  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  21  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  22  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  23  * Please see the License for the specific language governing rights and
  24  * limitations under the License.
  25  *
  26  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
  27  */
  28 /*      $NetBSD: msg.h,v 1.4 1994/06/29 06:44:43 cgd Exp $      */
  29
  30 /*
  31  * SVID compatible msg.h file
  32  *
  33  * Author:  Daniel Boulet
  34  *
  35  * Copyright 1993 Daniel Boulet and RTMX Inc.
  36  *
  37  * This system call was implemented by Daniel Boulet under contract from RTMX.
  38  *
  39  * Redistribution and use in source forms, with and without modification,
  40  * are permitted provided that this entire comment appears intact.
  41  *
  42  * Redistribution in binary form may occur without any restrictions.
  43  * Obviously, it would be nice if you gave credit where credit is due
  44  * but requiring it would be too onerous.
  45  *
  46  * This software is provided ``AS IS'' without any warranties of any kind.
  47  */
  48 /*
  49  * NOTICE: This file was modified by SPARTA, Inc. in 2005 to introduce
  50  * support for mandatory and extensible security protections.  This notice
  51  * is included in support of clause 2.2 (b) of the Apple Public License,
  52  * Version 2.0.
  53  */
  54
  55 #ifndef _SYS_MSG_H_
  56 #define _SYS_MSG_H_
  57
  58 #include <sys/appleapiopts.h>
  59
  60 #include <sys/_types.h>
  61 #include <sys/cdefs.h>
  62
  63 /*
  64  * [XSI] All of the symbols from <sys/ipc.h> SHALL be defined when this
  65  * header is included
  66  */
  67 #include <sys/ipc.h>
  68
  69
  70 /*
  71  * [XSI] The pid_t, time_t, key_t, size_t, and ssize_t types shall be
  72  * defined as described in <sys/types.h>.
  73  *
  74  * NOTE:        The definition of the key_t type is implicit from the
  75  *              inclusion of <sys/ipc.h>
  76  */
  77 #ifndef _PID_T
  78 typedef __darwin_pid_t          pid_t;
  79 #define _PID_T
  80 #endif
  81
  82 #ifndef _TIME_T
  83 #define _TIME_T
  84 typedef __darwin_time_t         time_t;
  85 #endif
  86
  87 #ifndef _SIZE_T
  88 #define _SIZE_T
  89 typedef __darwin_size_t         size_t;
  90 #endif
  91
  92 #ifndef _SSIZE_T
  93 #define _SSIZE_T
  94 typedef __darwin_ssize_t        ssize_t;
  95 #endif
  96
  97 /* [XSI] Used for the number of messages in the message queue */
  98 typedef unsigned long           msgqnum_t;
  99 typedef unsigned long long      user_msgqnum_t;
 100
 101 /* [XSI] Used for the number of bytes allowed in a message queue */
 102 typedef unsigned long           msglen_t;
 103 typedef unsigned long long      user_msglen_t;
 104
 105
 106 /*
 107  * Possible values for the fifth parameter to msgrcv(), in addition to the
 108  * IPC_NOWAIT flag, which is permitted.
 109  */
 110 #define MSG_NOERROR     010000          /* [XSI] No error if big message */
 111
 112
 113 /*
 114  * Technically, we should force all code references to the new structure
 115  * definition, not in just the standards conformance case, and leave the
 116  * legacy interface there for binary compatibility only.  Currently, we
 117  * are only forcing this for programs requesting standards conformance.
 118  */
 119 #if __DARWIN_UNIX03 || defined(KERNEL)
 120 #pragma pack(4)
 121 /*
 122  * Structure used internally.
 123  *
 124  * Structure whose address is passed as the third parameter to msgctl()
 125  * when the second parameter is IPC_SET or IPC_STAT.  In the case of the
 126  * IPC_SET command, only the msg_perm.{uid|gid|perm} and msg_qbytes are
 127  * honored.  In the case of IPC_STAT, only the fields indicated as [XSI]
 128  * mandated fields are guaranteed to meaningful: DO NOT depend on the
 129  * contents of the other fields.
 130  *
 131  * NOTES:       Reserved fields are not preserved across IPC_SET/IPC_STAT.
 132  */
 133 #if (defined(_POSIX_C_SOURCE) && !defined(_DARWIN_C_SOURCE))
 134 struct msqid_ds
 135 #else
 136 #define msqid_ds        __msqid_ds_new
 137 struct __msqid_ds_new
 138 #endif
 139 {
 140         struct __ipc_perm_new   msg_perm; /* [XSI] msg queue permissions */
 141         __int32_t       msg_first;      /* RESERVED: kernel use only */
 142         __int32_t       msg_last;       /* RESERVED: kernel use only */
 143         msglen_t        msg_cbytes;     /* # of bytes on the queue */
 144         msgqnum_t       msg_qnum;       /* [XSI] number of msgs on the queue */
 145         msglen_t        msg_qbytes;     /* [XSI] max bytes on the queue */
 146         pid_t           msg_lspid;      /* [XSI] pid of last msgsnd() */
 147         pid_t           msg_lrpid;      /* [XSI] pid of last msgrcv() */
 148         time_t          msg_stime;      /* [XSI] time of last msgsnd() */
 149         __int32_t       msg_pad1;       /* RESERVED: DO NOT USE */
 150         time_t          msg_rtime;      /* [XSI] time of last msgrcv() */
 151         __int32_t       msg_pad2;       /* RESERVED: DO NOT USE */
 152         time_t          msg_ctime;      /* [XSI] time of last msgctl() */
 153         __int32_t       msg_pad3;       /* RESERVED: DO NOT USE */
 154         __int32_t       msg_pad4[4];    /* RESERVED: DO NOT USE */
 155 };
 156 #pragma pack()
 157 #else   /* !__DARWIN_UNIX03 */
 158 #define msqid_ds        __msqid_ds_old
 159 #endif  /* !__DARWIN_UNIX03 */
 160
 161 #if !__DARWIN_UNIX03
 162 struct __msqid_ds_old {
 163         struct __ipc_perm_old   msg_perm; /* [XSI] msg queue permissions */
 164         __int32_t       msg_first;      /* RESERVED: kernel use only */
 165         __int32_t       msg_last;       /* RESERVED: kernel use only */
 166         msglen_t        msg_cbytes;     /* # of bytes on the queue */
 167         msgqnum_t       msg_qnum;       /* [XSI] number of msgs on the queue */
 168         msglen_t        msg_qbytes;     /* [XSI] max bytes on the queue */
 169         pid_t           msg_lspid;      /* [XSI] pid of last msgsnd() */
 170         pid_t           msg_lrpid;      /* [XSI] pid of last msgrcv() */
 171         time_t          msg_stime;      /* [XSI] time of last msgsnd() */
 172         __int32_t       msg_pad1;       /* RESERVED: DO NOT USE */
 173         time_t          msg_rtime;      /* [XSI] time of last msgrcv() */
 174         __int32_t       msg_pad2;       /* RESERVED: DO NOT USE */
 175         time_t          msg_ctime;      /* [XSI] time of last msgctl() */
 176         __int32_t       msg_pad3;       /* RESERVED: DO NOT USE */
 177         __int32_t       msg_pad4[4];    /* RESERVED: DO NOT USE */
 178 };
 179 #endif  /* !__DARWIN_UNIX03 */
 180
 181 #ifdef KERNEL
 182 #ifdef __APPLE_API_PRIVATE
 183 #include <machine/types.h>
 184
 185 #if __DARWIN_ALIGN_NATURAL
 186 #pragma options align=natural
 187 #endif
 188
 189 struct user_msqid_ds {
 190         struct ipc_perm msg_perm;       /* [XSI] msg queue permissions */
 191         struct msg      *msg_first;     /* first message in the queue */
 192         struct msg      *msg_last;      /* last message in the queue */
 193         user_msglen_t   msg_cbytes;     /* # of bytes on the queue */
 194         user_msgqnum_t  msg_qnum;       /* [XSI] number of msgs on the queue */
 195         user_msglen_t   msg_qbytes;     /* [XSI] max bytes on the queue */
 196         pid_t           msg_lspid;      /* [XSI] pid of last msgsnd() */
 197         pid_t           msg_lrpid;      /* [XSI] pid of last msgrcv() */
 198         user_time_t     msg_stime;      /* [XSI] time of last msgsnd() */
 199         __int32_t       msg_pad1;       /* RESERVED: DO NOT USE */
 200         user_time_t     msg_rtime;      /* [XSI] time of last msgrcv() */
 201         __int32_t       msg_pad2;       /* RESERVED: DO NOT USE */
 202         user_time_t     msg_ctime;      /* [XSI] time of last msgctl() */
 203         __int32_t       msg_pad3;       /* RESERVED: DO NOT USE */
 204         __int32_t       msg_pad4[4];
 205 };
 206
 207 #if __DARWIN_ALIGN_NATURAL
 208 #pragma options align=reset
 209 #endif
 210
 211 struct label;
 212
 213 /*
 214  * Kernel wrapper for the user-level structure
 215  */
 216 struct msqid_kernel {
 217         struct  user_msqid_ds u;
 218         struct  label *label;   /* MAC framework label */
 219 };
 220
 221 #endif  /* __APPLE_API_PRIVATE */
 222 #endif  /* KERNEL */
 223
 224
 225 #if !defined(_POSIX_C_SOURCE) || defined(_DARWIN_C_SOURCE)
 226 #ifdef __APPLE_API_UNSTABLE
 227 /* XXX kernel only; protect with macro later */
 228
 229 struct msg {
 230         struct msg      *msg_next;      /* next msg in the chain */
 231         long            msg_type;       /* type of this message */
 232                                         /* >0 -> type of this message */
 233                                         /* 0 -> free header */
 234         unsigned short  msg_ts;         /* size of this message */
 235         short           msg_spot;       /* location of msg start in buffer */
 236         struct label    *label;         /* MAC label */
 237 };
 238
 239 /*
 240  * Example structure describing a message whose address is to be passed as
 241  * the second argument to the functions msgrcv() and msgsnd().  The only
 242  * actual hard requirement is that the first field be of type long, and
 243  * contain the message type.  The user is encouraged to define their own
 244  * application specific structure; this definition is included solely for
 245  * backward compatability with existing source code.
 246  */
 247 struct mymsg {
 248         long    mtype;          /* message type (+ve integer) */
 249         char    mtext[1];       /* message body */
 250 };
 251
 252 /*
 253  * Based on the configuration parameters described in an SVR2 (yes, two)
 254  * config(1m) man page.
 255  *
 256  * Each message is broken up and stored in segments that are msgssz bytes
 257  * long.  For efficiency reasons, this should be a power of two.  Also,
 258  * it doesn't make sense if it is less than 8 or greater than about 256.
 259  * Consequently, msginit in kern/sysv_msg.c checks that msgssz is a power of
 260  * two between 8 and 1024 inclusive (and panic's if it isn't).
 261  */
 262 struct msginfo {
 263         int     msgmax,         /* max chars in a message */
 264                 msgmni,         /* max message queue identifiers */
 265                 msgmnb,         /* max chars in a queue */
 266                 msgtql,         /* max messages in system */
 267                 msgssz,         /* size of a message segment (see notes above) */
 268                 msgseg;         /* number of message segments */
 269 };
 270 #ifdef KERNEL
 271 extern struct msginfo   msginfo;
 272
 273 #ifndef MSGSSZ
 274 #define MSGSSZ  8               /* Each segment must be 2^N long */
 275 #endif
 276 #ifndef MSGSEG
 277 #define MSGSEG  2048            /* must be less than 32767 */
 278 #endif
 279 #define MSGMAX  (MSGSSZ*MSGSEG)
 280 #ifndef MSGMNB
 281 #define MSGMNB  2048            /* max # of bytes in a queue */
 282 #endif
 283 #ifndef MSGMNI
 284 #define MSGMNI  40
 285 #endif
 286 #ifndef MSGTQL
 287 #define MSGTQL  40
 288 #endif
 289
 290 /*
 291  * macros to convert between msqid_ds's and msqid's.
 292  * (specific to this implementation)
 293  */
 294 #define MSQID(ix,ds)    ((ix) & 0xffff | (((ds).msg_perm.seq << 16) & 0xffff0000))
 295 #define MSQID_IX(id)    ((id) & 0xffff)
 296 #define MSQID_SEQ(id)   (((id) >> 16) & 0xffff)
 297
 298 /*
 299  * The rest of this file is specific to this particular implementation.
 300  */
 301
 302
 303 /*
 304  * Stuff allocated in machdep.h
 305  */
 306 struct msgmap {
 307         short   next;           /* next segment in buffer */
 308                                 /* -1 -> available */
 309                                 /* 0..(MSGSEG-1) -> index of next segment */
 310 };
 311
 312 /* The following four externs really, really need to die; should be static */
 313 extern char *msgpool;           /* MSGMAX byte long msg buffer pool */
 314 extern struct msgmap *msgmaps;  /* MSGSEG msgmap structures */
 315 extern struct msg *msghdrs;     /* MSGTQL msg headers */
 316 extern struct msqid_kernel *msqids;     /* MSGMNI user_msqid_ds struct's */
 317
 318 #define MSG_LOCKED      01000   /* Is this msqid_ds locked? */
 319
 320 #endif  /* KERNEL */
 321 #endif  /* __APPLE_API_UNSTABLE */
 322 #endif  /* (!_POSIX_C_SOURCE || _DARWIN_C_SOURCE) */
 323
 324 #ifndef KERNEL
 325
 326 __BEGIN_DECLS
 327 #if !defined(_POSIX_C_SOURCE) || defined(_DARWIN_C_SOURCE)
 328 int msgsys(int, ...);
 329 #endif  /* (!_POSIX_C_SOURCE || _DARWIN_C_SOURCE) */
 330 int msgctl(int, int, struct msqid_ds *) __DARWIN_ALIAS(msgctl);
 331 int msgget(key_t, int);
 332 ssize_t msgrcv(int, void *, size_t, long, int) __DARWIN_ALIAS_C(msgrcv);
 333 int msgsnd(int, const void *, size_t, int) __DARWIN_ALIAS_C(msgsnd);
 334 __END_DECLS
 335
 336 #endif /* !KERNEL */
 337
 338 #endif /* !_SYS_MSG_H_ */
 339
 340