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: sem.h,v 1.5 1994/06/29 06:45:15 cgd Exp $ */ 29 30/* 31 * SVID compatible sem.h file 32 * 33 * Author: Daniel Boulet 34 * John Bellardo modified the implementation for Darwin. 12/2000 35 */ 36 37#ifndef _SYS_SEM_H_ 38#define _SYS_SEM_H_ 39 40 41#include <sys/cdefs.h> 42#include <sys/_types.h> 43 44/* 45 * [XSI] All of the symbols from <sys/ipc.h> SHALL be defined 46 * when this header is included 47 */ 48#include <sys/ipc.h> 49 50 51/* 52 * [XSI] The pid_t, time_t, key_t, and size_t types shall be defined as 53 * described in <sys/types.h>. 54 * 55 * NOTE: The definition of the key_t type is implicit from the 56 * inclusion of <sys/ipc.h> 57 */ 58#ifndef _PID_T 59typedef __darwin_pid_t pid_t; 60#define _PID_T 61#endif 62 63#ifndef _TIME_T 64#define _TIME_T 65typedef __darwin_time_t time_t; 66#endif 67 68#ifndef _SIZE_T 69#define _SIZE_T 70typedef __darwin_size_t size_t; 71#endif 72 73/* 74 * Technically, we should force all code references to the new structure 75 * definition, not in just the standards conformance case, and leave the 76 * legacy interface there for binary compatibility only. Currently, we 77 * are only forcing this for programs requesting standards conformance. 78 */ 79#if __DARWIN_UNIX03 || defined(KERNEL) 80#pragma pack(4) 81/* 82 * Structure used internally. 83 * 84 * This structure is exposed because standards dictate that it is used as 85 * the semun union member 'buf' as the fourth argment to semctl() when the 86 * third argument is IPC_STAT or IPC_SET. 87 * 88 * Note: only the fields sem_perm, sem_nsems, sem_otime, and sem_ctime 89 * are meaningful in user space. 90 */ 91#if (defined(_POSIX_C_SOURCE) && !defined(_DARWIN_C_SOURCE)) 92struct semid_ds 93#else 94#define semid_ds __semid_ds_new 95struct __semid_ds_new 96#endif 97{ 98 struct __ipc_perm_new sem_perm; /* [XSI] operation permission struct */ 99 __int32_t sem_base; /* 32 bit base ptr for semaphore set */ 100 unsigned short sem_nsems; /* [XSI] number of sems in set */ 101 time_t sem_otime; /* [XSI] last operation time */ 102 __int32_t sem_pad1; /* RESERVED: DO NOT USE! */ 103 time_t sem_ctime; /* [XSI] last change time */ 104 /* Times measured in secs since */ 105 /* 00:00:00 GMT, Jan. 1, 1970 */ 106 __int32_t sem_pad2; /* RESERVED: DO NOT USE! */ 107 __int32_t sem_pad3[4]; /* RESERVED: DO NOT USE! */ 108}; 109#pragma pack() 110#else /* !__DARWIN_UNIX03 */ 111#define semid_ds __semid_ds_old 112#endif /* __DARWIN_UNIX03 */ 113 114#if !__DARWIN_UNIX03 115struct __semid_ds_old { 116 struct __ipc_perm_old sem_perm; /* [XSI] operation permission struct */ 117 __int32_t sem_base; /* 32 bit base ptr for semaphore set */ 118 unsigned short sem_nsems; /* [XSI] number of sems in set */ 119 time_t sem_otime; /* [XSI] last operation time */ 120 __int32_t sem_pad1; /* RESERVED: DO NOT USE! */ 121 time_t sem_ctime; /* [XSI] last change time */ 122 /* Times measured in secs since */ 123 /* 00:00:00 GMT, Jan. 1, 1970 */ 124 __int32_t sem_pad2; /* RESERVED: DO NOT USE! */ 125 __int32_t sem_pad3[4]; /* RESERVED: DO NOT USE! */ 126}; 127#endif /* !__DARWIN_UNIX03 */ 128 129/* 130 * Possible values for the third argument to semctl() 131 */ 132#define GETNCNT 3 /* [XSI] Return the value of semncnt {READ} */ 133#define GETPID 4 /* [XSI] Return the value of sempid {READ} */ 134#define GETVAL 5 /* [XSI] Return the value of semval {READ} */ 135#define GETALL 6 /* [XSI] Return semvals into arg.array {READ} */ 136#define GETZCNT 7 /* [XSI] Return the value of semzcnt {READ} */ 137#define SETVAL 8 /* [XSI] Set the value of semval to arg.val {ALTER} */ 138#define SETALL 9 /* [XSI] Set semvals from arg.array {ALTER} */ 139 140 141/* A semaphore; this is an anonymous structure, not for external use */ 142struct sem { 143 unsigned short semval; /* semaphore value */ 144 pid_t sempid; /* pid of last operation */ 145 unsigned short semncnt; /* # awaiting semval > cval */ 146 unsigned short semzcnt; /* # awaiting semval == 0 */ 147}; 148 149 150/* 151 * Structure of array element for second argument to semop() 152 */ 153struct sembuf { 154 unsigned short sem_num; /* [XSI] semaphore # */ 155 short sem_op; /* [XSI] semaphore operation */ 156 short sem_flg; /* [XSI] operation flags */ 157}; 158 159/* 160 * Possible flag values for sem_flg 161 */ 162#define SEM_UNDO 010000 /* [XSI] Set up adjust on exit entry */ 163 164 165#if !defined(_POSIX_C_SOURCE) || defined(_DARWIN_C_SOURCE) 166 167/* 168 * Union used as the fourth argment to semctl() in all cases. Specific 169 * member values are used for different values of the third parameter: 170 * 171 * Command Member 172 * ------------------------------------------- ------ 173 * GETALL, SETALL array 174 * SETVAL val 175 * IPC_STAT, IPC_SET buf 176 * 177 * The union definition is intended to be defined by the user application 178 * in conforming applications; it is provided here for two reasons: 179 * 180 * 1) Historical source compatability for non-conforming applications 181 * expecting this header to declare the union type on their behalf 182 * 183 * 2) Documentation; specifically, 64 bit applications that do not pass 184 * this structure for 'val', or, alternately, a 64 bit type, will 185 * not function correctly 186 */ 187union semun { 188 int val; /* value for SETVAL */ 189 struct semid_ds *buf; /* buffer for IPC_STAT & IPC_SET */ 190 unsigned short *array; /* array for GETALL & SETALL */ 191}; 192typedef union semun semun_t; 193 194 195/* 196 * Permissions 197 */ 198#define SEM_A 0200 /* alter permission */ 199#define SEM_R 0400 /* read permission */ 200 201#endif /* (!_POSIX_C_SOURCE || _DARWIN_C_SOURCE) */ 202 203 204 205#ifndef KERNEL 206 207__BEGIN_DECLS 208#if !defined(_POSIX_C_SOURCE) || defined(_DARWIN_C_SOURCE) 209int semsys(int, ...); 210#endif /* (!_POSIX_C_SOURCE || _DARWIN_C_SOURCE) */ 211int semctl(int, int, int, ...) __DARWIN_ALIAS(semctl); 212int semget(key_t, int, int); 213int semop(int, struct sembuf *, size_t); 214__END_DECLS 215 216#endif /* !KERNEL */ 217 218#endif /* !_SEM_H_ */ 219