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 #ifndef _PID_T
  85 typedef __darwin_pid_t  pid_t;
  86 #define _PID_T
  87 #endif
  88
  89 #ifndef _TIME_T
  90 #define _TIME_T
  91 typedef __darwin_time_t time_t;
  92 #endif
  93
  94 #ifndef _SIZE_T
  95 #define _SIZE_T
  96 typedef __darwin_size_t size_t;
  97 #endif
  98
  99 /*
 100  * [XSI] The unsigned integer type used for the number of current attaches
 101  * that MUST be able to store values at least as large as a type unsigned
 102  * short.
 103  */
 104 typedef unsigned short  shmatt_t;
 105
 106
 107 /*
 108  * Possible flag values which may be OR'ed into the third argument to
 109  * shmat()
 110  */
 111 #define SHM_RDONLY      010000  /* [XSI] Attach read-only (else read-write) */
 112 #define SHM_RND         020000  /* [XSI] Round attach address to SHMLBA */
 113
 114 /*
 115  * This value is symbolic, and generally not expected to be sed by user
 116  * programs directly, although such ise is permitted by the standard.  Its
 117  * value in our implementation is equal to the number of bytes per page.
 118  *
 119  * NOTE:        We DO NOT obtain this value from the appropriate system
 120  *              headers at this time, to avoid the resulting namespace
 121  *              pollution, which is why we discourages its use.
 122  */
 123 #define SHMLBA      4096        /* [XSI] Segment low boundary address multiple*/
 124
 125 /* "official" access mode definitions; somewhat braindead since you have
 126    to specify (SHM_* >> 3) for group and (SHM_* >> 6) for world permissions */
 127 #define SHM_R       (IPC_R)
 128 #define SHM_W       (IPC_W)
 129
 130 /*
 131  * Technically, we should force all code references to the new structure
 132  * definition, not in just the standards conformance case, and leave the
 133  * legacy interface there for binary compatibility only.  Currently, we
 134  * are only forcing this for programs requesting standards conformance.
 135  */
 136 #if defined(__POSIX_C_SOURCE) || defined(kernel) || defined(__LP64__)
 137 /*
 138  * Structure used internally.
 139  *
 140  * This structure is exposed because standards dictate that it is used as
 141  * the third argment to shmctl().
 142  *
 143  * NOTE:        The field shm_internal is not meaningful in user space,
 144  *              and mst not be used there.
 145  */
 146 struct __shmid_ds_new {
 147         struct __ipc_perm_new shm_perm; /* [XSI] Operation permission value */
 148         size_t          shm_segsz;      /* [XSI] Size of segment in bytes */
 149         pid_t           shm_lpid;       /* [XSI] PID of last shared memory op */
 150         pid_t           shm_cpid;       /* [XSI] PID of creator */
 151         short           shm_nattch;     /* [XSI] Number of current attaches */
 152         time_t          shm_atime;      /* [XSI] Time of last shmat() */
 153         time_t          shm_dtime;      /* [XSI] Time of last shmdt() */
 154         time_t          shm_ctime;      /* [XSI] Time of last shmctl() change */
 155         void            *shm_internal;  /* reserved for kernel use */
 156 };
 157 #define shmid_ds        __shmid_ds_new
 158 #else   /* !_POSIX_C_SOURCE */
 159 #define shmid_ds        __shmid_ds_old
 160 #endif  /* !_POSIX_C_SOURCE */
 161
 162 #if !defined(__POSIX_C_SOURCE) && !defined(__LP64__)
 163 struct __shmid_ds_old {
 164         struct __ipc_perm_old shm_perm; /* [XSI] Operation permission value */
 165         size_t          shm_segsz;      /* [XSI] Size of segment in bytes */
 166         pid_t           shm_lpid;       /* [XSI] PID of last shared memory op */
 167         pid_t           shm_cpid;       /* [XSI] PID of creator */
 168         short           shm_nattch;     /* [XSI] Number of current attaches */
 169         time_t          shm_atime;      /* [XSI] Time of last shmat() */
 170         time_t          shm_dtime;      /* [XSI] Time of last shmdt() */
 171         time_t          shm_ctime;      /* [XSI] Time of last shmctl() change */
 172         void            *shm_internal;  /* reserved for kernel use */
 173 };
 174 #endif  /* !_POSIX_C_SOURCE */
 175
 176 #ifndef KERNEL
 177
 178 __BEGIN_DECLS
 179 #ifndef _POSIX_C_SOURCE
 180 int     shmsys(int, ...);
 181 #endif /* !_POSIX_C_SOURCE */
 182 void    *shmat (int, const void *, int);
 183 int     shmctl(int, int, struct shmid_ds *) __DARWIN_ALIAS(shmctl);
 184 int     shmdt(const void *);
 185 int     shmget(key_t, size_t, int);
 186 __END_DECLS
 187
 188 #endif /* !KERNEL */
 189
 190 #endif /* !_SYS_SHM_H_ */