bsd/sys/shm.h

   1 /*
   2  * Copyright (c) 2000-2002 Apple Computer, 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: shm.h,v 1.15 1994/06/29 06:45:17 cgd Exp $     */
  29
  30 /*
  31  * Copyright (c) 1994 Adam Glass
  32  * All rights reserved.
  33  *
  34  * Redistribution and use in source and binary forms, with or without
  35  * modification, are permitted provided that the following conditions
  36  * are met:
  37  * 1. Redistributions of source code must retain the above copyright
  38  *    notice, this list of conditions and the following disclaimer.
  39  * 2. Redistributions in binary form must reproduce the above copyright
  40  *    notice, this list of conditions and the following disclaimer in the
  41  *    documentation and/or other materials provided with the distribution.
  42  * 3. All advertising materials mentioning features or use of this software
  43  *    must display the following acknowledgement:
  44  *      This product includes software developed by Adam Glass.
  45  * 4. The name of the author may not be used to endorse or promote products
  46  *    derived from this software without specific prior written permission
  47  *
  48  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  49  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  50  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  51  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  52  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  53  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  54  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  55  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  56  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  57  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  58  */
  59
  60 /*
  61  * As defined+described in "X/Open System Interfaces and Headers"
  62  *                         Issue 4, p. XXX
  63  */
  64
  65 #ifndef _SYS_SHM_H_
  66 #define _SYS_SHM_H_
  67
  68 #include <sys/cdefs.h>
  69 #include <sys/_types.h>
  70
  71 /*
  72  * [XSI]        All of the symbols from <sys/ipc.h> SHALL be defined
  73  *              when this header is included
  74  */
  75 #include <sys/ipc.h>
  76
  77 /*
  78  * [XSI] The pid_t, time_t, key_t, and size_t types shall be defined as
  79  * described in <sys/types.h>.
  80  *
  81  * NOTE:        The definition of the key_t type is implicit from the
  82  *              inclusion of <sys/ipc.h>
  83  */
  84 #include <sys/_types/_pid_t.h>
  85 #include <sys/_types/_time_t.h>
  86 #include <sys/_types/_size_t.h>
  87
  88 /*
  89  * [XSI] The unsigned integer type used for the number of current attaches
  90  * that MUST be able to store values at least as large as a type unsigned
  91  * short.
  92  */
  93 typedef unsigned short  shmatt_t;
  94
  95
  96 /*
  97  * Possible flag values which may be OR'ed into the third argument to
  98  * shmat()
  99  */
 100 #define SHM_RDONLY      010000  /* [XSI] Attach read-only (else read-write) */
 101 #define SHM_RND         020000  /* [XSI] Round attach address to SHMLBA */
 102
 103 /*
 104  * This value is symbolic, and generally not expected to be sed by user
 105  * programs directly, although such ise is permitted by the standard.  Its
 106  * value in our implementation is equal to the number of bytes per page.
 107  *
 108  * NOTE:        We DO NOT obtain this value from the appropriate system
 109  *              headers at this time, to avoid the resulting namespace
 110  *              pollution, which is why we discourages its use.
 111  */
 112 #define SHMLBA      4096        /* [XSI] Segment low boundary address multiple*/
 113
 114 /* "official" access mode definitions; somewhat braindead since you have
 115    to specify (SHM_* >> 3) for group and (SHM_* >> 6) for world permissions */
 116 #define SHM_R       (IPC_R)
 117 #define SHM_W       (IPC_W)
 118
 119 #pragma pack(4)
 120
 121 /*
 122  * Technically, we should force all code references to the new structure
 123  * definition, not in just the standards conformance case, and leave the
 124  * legacy interface there for binary compatibility only.  Currently, we
 125  * are only forcing this for programs requesting standards conformance.
 126  */
 127 #if __DARWIN_UNIX03 || defined(KERNEL)
 128 /*
 129  * Structure used internally.
 130  *
 131  * This structure is exposed because standards dictate that it is used as
 132  * the third argment to shmctl().
 133  *
 134  * NOTE:        The field shm_internal is not meaningful in user space,
 135  *              and must not be used there.
 136  */
 137 #if (defined(_POSIX_C_SOURCE) && !defined(_DARWIN_C_SOURCE))
 138 struct shmid_ds
 139 #else
 140 #define shmid_ds        __shmid_ds_new
 141 struct __shmid_ds_new
 142 #endif
 143 {
 144         struct __ipc_perm_new shm_perm; /* [XSI] Operation permission value */
 145         size_t          shm_segsz;      /* [XSI] Size of segment in bytes */
 146         pid_t           shm_lpid;       /* [XSI] PID of last shared memory op */
 147         pid_t           shm_cpid;       /* [XSI] PID of creator */
 148         shmatt_t        shm_nattch;     /* [XSI] Number of current attaches */
 149         time_t          shm_atime;      /* [XSI] Time of last shmat() */
 150         time_t          shm_dtime;      /* [XSI] Time of last shmdt() */
 151         time_t          shm_ctime;      /* [XSI] Time of last shmctl() change */
 152         void            *shm_internal;  /* reserved for kernel use */
 153 };
 154 #else   /* !__DARWIN_UNIX03 */
 155 #define shmid_ds        __shmid_ds_old
 156 #endif  /* !__DARWIN_UNIX03 */
 157
 158 #if !__DARWIN_UNIX03
 159 struct __shmid_ds_old {
 160         struct __ipc_perm_old shm_perm; /* [XSI] Operation permission value */
 161         size_t          shm_segsz;      /* [XSI] Size of segment in bytes */
 162         pid_t           shm_lpid;       /* [XSI] PID of last shared memory op */
 163         pid_t           shm_cpid;       /* [XSI] PID of creator */
 164         shmatt_t        shm_nattch;     /* [XSI] Number of current attaches */
 165         time_t          shm_atime;      /* [XSI] Time of last shmat() */
 166         time_t          shm_dtime;      /* [XSI] Time of last shmdt() */
 167         time_t          shm_ctime;      /* [XSI] Time of last shmctl() change */
 168         void            *shm_internal;  /* reserved for kernel use */
 169 };
 170 #endif  /* !__DARWIN_UNIX03 */
 171
 172 #pragma pack()
 173
 174 #ifndef KERNEL
 175
 176 __BEGIN_DECLS
 177 #if !defined(_POSIX_C_SOURCE) || defined(_DARWIN_C_SOURCE)
 178 int     shmsys(int, ...);
 179 #endif /* (!_POSIX_C_SOURCE || _DARWIN_C_SOURCE) */
 180 void    *shmat (int, const void *, int);
 181 int     shmctl(int, int, struct shmid_ds *) __DARWIN_ALIAS(shmctl);
 182 int     shmdt(const void *);
 183 int     shmget(key_t, size_t, int);
 184 __END_DECLS
 185
 186 #endif /* !KERNEL */
 187
 188 #endif /* !_SYS_SHM_H_ */