bsd/sys/shm.h

   1 /*
   2  * Copyright (c) 2006 Apple Computer, Inc. All Rights Reserved.
   3  *
   4  * @APPLE_LICENSE_OSREFERENCE_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
  10  * License may not be used to create, or enable the creation or
  11  * redistribution of, unlawful or unlicensed copies of an Apple operating
  12  * system, or to circumvent, violate, or enable the circumvention or
  13  * violation of, any terms of an Apple operating system software license
  14  * agreement.
  15  *
  16  * Please obtain a copy of the License at
  17  * http://www.opensource.apple.com/apsl/ and read it before using this
  18  * file.
  19  *
  20  * The Original Code and all software distributed under the License are
  21  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  22  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  23  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  24  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  25  * Please see the License for the specific language governing rights and
  26  * limitations under the License.
  27  *
  28  * @APPLE_LICENSE_OSREFERENCE_HEADER_END@
  29  */
  30 /*      $NetBSD: shm.h,v 1.15 1994/06/29 06:45:17 cgd Exp $     */
  31
  32 /*
  33  * Copyright (c) 1994 Adam Glass
  34  * All rights reserved.
  35  *
  36  * Redistribution and use in source and binary forms, with or without
  37  * modification, are permitted provided that the following conditions
  38  * are met:
  39  * 1. Redistributions of source code must retain the above copyright
  40  *    notice, this list of conditions and the following disclaimer.
  41  * 2. Redistributions in binary form must reproduce the above copyright
  42  *    notice, this list of conditions and the following disclaimer in the
  43  *    documentation and/or other materials provided with the distribution.
  44  * 3. All advertising materials mentioning features or use of this software
  45  *    must display the following acknowledgement:
  46  *      This product includes software developed by Adam Glass.
  47  * 4. The name of the author may not be used to endorse or promote products
  48  *    derived from this software without specific prior written permission
  49  *
  50  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  51  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  52  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  53  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  54  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  55  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  56  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  57  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  58  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  59  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  60  */
  61
  62 /*
  63  * As defined+described in "X/Open System Interfaces and Headers"
  64  *                         Issue 4, p. XXX
  65  */
  66
  67 #ifndef _SYS_SHM_H_
  68 #define _SYS_SHM_H_
  69
  70 #include <sys/cdefs.h>
  71 #include <sys/_types.h>
  72
  73 /*
  74  * [XSI]        All of the symbols from <sys/ipc.h> SHALL be defined
  75  *              when this header is included
  76  */
  77 #include <sys/ipc.h>
  78
  79 /*
  80  * [XSI] The pid_t, time_t, key_t, and size_t types shall be defined as
  81  * described in <sys/types.h>.
  82  *
  83  * NOTE:        The definition of the key_t type is implicit from the
  84  *              inclusion of <sys/ipc.h>
  85  */
  86 #ifndef _PID_T
  87 typedef __darwin_pid_t  pid_t;
  88 #define _PID_T
  89 #endif
  90
  91 #ifndef _TIME_T
  92 #define _TIME_T
  93 typedef __darwin_time_t time_t;
  94 #endif
  95
  96 #ifndef _SIZE_T
  97 #define _SIZE_T
  98 typedef __darwin_size_t size_t;
  99 #endif
 100
 101 /*
 102  * [XSI] The unsigned integer type used for the number of current attaches
 103  * that MUST be able to store values at least as large as a type unsigned
 104  * short.
 105  */
 106 typedef unsigned short  shmatt_t;
 107
 108
 109 /*
 110  * Possible flag values which may be OR'ed into the third argument to
 111  * shmat()
 112  */
 113 #define SHM_RDONLY      010000  /* [XSI] Attach read-only (else read-write) */
 114 #define SHM_RND         020000  /* [XSI] Round attach address to SHMLBA */
 115
 116 /*
 117  * This value is symbolic, and generally not expected to be sed by user
 118  * programs directly, although such ise is permitted by the standard.  Its
 119  * value in our implementation is equal to the number of bytes per page.
 120  *
 121  * NOTE:        We DO NOT obtain this value from the appropriate system
 122  *              headers at this time, to avoid the resulting namespace
 123  *              pollution, which is why we discourages its use.
 124  */
 125 #define SHMLBA      4096        /* [XSI] Segment low boundary address multiple*/
 126
 127 /* "official" access mode definitions; somewhat braindead since you have
 128    to specify (SHM_* >> 3) for group and (SHM_* >> 6) for world permissions */
 129 #define SHM_R       (IPC_R)
 130 #define SHM_W       (IPC_W)
 131
 132 /*
 133  * Technically, we should force all code references to the new structure
 134  * definition, not in just the standards conformance case, and leave the
 135  * legacy interface there for binary compatibility only.  Currently, we
 136  * are only forcing this for programs requesting standards conformance.
 137  */
 138 #if defined(__POSIX_C_SOURCE) || defined(kernel) || defined(__LP64__)
 139 /*
 140  * Structure used internally.
 141  *
 142  * This structure is exposed because standards dictate that it is used as
 143  * the third argment to shmctl().
 144  *
 145  * NOTE:        The field shm_internal is not meaningful in user space,
 146  *              and mst not be used there.
 147  */
 148 struct __shmid_ds_new {
 149         struct __ipc_perm_new shm_perm; /* [XSI] Operation permission value */
 150         size_t          shm_segsz;      /* [XSI] Size of segment in bytes */
 151         pid_t           shm_lpid;       /* [XSI] PID of last shared memory op */
 152         pid_t           shm_cpid;       /* [XSI] PID of creator */
 153         short           shm_nattch;     /* [XSI] Number of current attaches */
 154         time_t          shm_atime;      /* [XSI] Time of last shmat() */
 155         time_t          shm_dtime;      /* [XSI] Time of last shmdt() */
 156         time_t          shm_ctime;      /* [XSI] Time of last shmctl() change */
 157         void            *shm_internal;  /* reserved for kernel use */
 158 };
 159 #define shmid_ds        __shmid_ds_new
 160 #else   /* !_POSIX_C_SOURCE */
 161 #define shmid_ds        __shmid_ds_old
 162 #endif  /* !_POSIX_C_SOURCE */
 163
 164 #if !defined(__POSIX_C_SOURCE) && !defined(__LP64__)
 165 struct __shmid_ds_old {
 166         struct __ipc_perm_old shm_perm; /* [XSI] Operation permission value */
 167         size_t          shm_segsz;      /* [XSI] Size of segment in bytes */
 168         pid_t           shm_lpid;       /* [XSI] PID of last shared memory op */
 169         pid_t           shm_cpid;       /* [XSI] PID of creator */
 170         short           shm_nattch;     /* [XSI] Number of current attaches */
 171         time_t          shm_atime;      /* [XSI] Time of last shmat() */
 172         time_t          shm_dtime;      /* [XSI] Time of last shmdt() */
 173         time_t          shm_ctime;      /* [XSI] Time of last shmctl() change */
 174         void            *shm_internal;  /* reserved for kernel use */
 175 };
 176 #endif  /* !_POSIX_C_SOURCE */
 177
 178 #ifndef KERNEL
 179
 180 __BEGIN_DECLS
 181 #ifndef _POSIX_C_SOURCE
 182 int     shmsys(int, ...);
 183 #endif /* !_POSIX_C_SOURCE */
 184 void    *shmat (int, const void *, int);
 185 int     shmctl(int, int, struct shmid_ds *) __DARWIN_ALIAS(shmctl);
 186 int     shmdt(const void *);
 187 int     shmget(key_t, size_t, int);
 188 __END_DECLS
 189
 190 #endif /* !KERNEL */
 191
 192 #endif /* !_SYS_SHM_H_ */