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