gems-kernel/source/THIRDPARTY/xnu/bsd/sys/sem.h
2024-06-03 11:29:39 -05:00

208 lines
7.2 KiB
C

/*
* Copyright (c) 2000-2007 Apple Inc. All rights reserved.
*
* @APPLE_OSREFERENCE_LICENSE_HEADER_START@
*
* This file contains Original Code and/or Modifications of Original Code
* as defined in and that are subject to the Apple Public Source License
* Version 2.0 (the 'License'). You may not use this file except in
* compliance with the License. The rights granted to you under the License
* may not be used to create, or enable the creation or redistribution of,
* unlawful or unlicensed copies of an Apple operating system, or to
* circumvent, violate, or enable the circumvention or violation of, any
* terms of an Apple operating system software license agreement.
*
* Please obtain a copy of the License at
* http://www.opensource.apple.com/apsl/ and read it before using this file.
*
* The Original Code and all software distributed under the License are
* distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
* Please see the License for the specific language governing rights and
* limitations under the License.
*
* @APPLE_OSREFERENCE_LICENSE_HEADER_END@
*/
/* $NetBSD: sem.h,v 1.5 1994/06/29 06:45:15 cgd Exp $ */
/*
* SVID compatible sem.h file
*
* Author: Daniel Boulet
* John Bellardo modified the implementation for Darwin. 12/2000
*/
#ifndef _SYS_SEM_H_
#define _SYS_SEM_H_
#include <sys/cdefs.h>
#include <sys/_types.h>
#include <machine/types.h> /* __int32_t */
/*
* [XSI] All of the symbols from <sys/ipc.h> SHALL be defined
* when this header is included
*/
#include <sys/ipc.h>
/*
* [XSI] The pid_t, time_t, key_t, and size_t types shall be defined as
* described in <sys/types.h>.
*
* NOTE: The definition of the key_t type is implicit from the
* inclusion of <sys/ipc.h>
*/
#include <sys/_types/_pid_t.h>
#include <sys/_types/_time_t.h>
#include <sys/_types/_size_t.h>
/*
* Technically, we should force all code references to the new structure
* definition, not in just the standards conformance case, and leave the
* legacy interface there for binary compatibility only. Currently, we
* are only forcing this for programs requesting standards conformance.
*/
#if __DARWIN_UNIX03 || defined(KERNEL)
#pragma pack(4)
/*
* Structure used internally.
*
* This structure is exposed because standards dictate that it is used as
* the semun union member 'buf' as the fourth argment to semctl() when the
* third argument is IPC_STAT or IPC_SET.
*
* Note: only the fields sem_perm, sem_nsems, sem_otime, and sem_ctime
* are meaningful in user space.
*/
#if (defined(_POSIX_C_SOURCE) && !defined(_DARWIN_C_SOURCE))
struct semid_ds
#else
#define semid_ds __semid_ds_new
struct __semid_ds_new
#endif
{
struct __ipc_perm_new sem_perm; /* [XSI] operation permission struct */
__int32_t sem_base; /* 32 bit base ptr for semaphore set */
unsigned short sem_nsems; /* [XSI] number of sems in set */
time_t sem_otime; /* [XSI] last operation time */
__int32_t sem_pad1; /* RESERVED: DO NOT USE! */
time_t sem_ctime; /* [XSI] last change time */
/* Times measured in secs since */
/* 00:00:00 GMT, Jan. 1, 1970 */
__int32_t sem_pad2; /* RESERVED: DO NOT USE! */
__int32_t sem_pad3[4]; /* RESERVED: DO NOT USE! */
};
#pragma pack()
#else /* !__DARWIN_UNIX03 */
#define semid_ds __semid_ds_old
#endif /* __DARWIN_UNIX03 */
#if !__DARWIN_UNIX03
struct __semid_ds_old {
struct __ipc_perm_old sem_perm; /* [XSI] operation permission struct */
__int32_t sem_base; /* 32 bit base ptr for semaphore set */
unsigned short sem_nsems; /* [XSI] number of sems in set */
time_t sem_otime; /* [XSI] last operation time */
__int32_t sem_pad1; /* RESERVED: DO NOT USE! */
time_t sem_ctime; /* [XSI] last change time */
/* Times measured in secs since */
/* 00:00:00 GMT, Jan. 1, 1970 */
__int32_t sem_pad2; /* RESERVED: DO NOT USE! */
__int32_t sem_pad3[4]; /* RESERVED: DO NOT USE! */
};
#endif /* !__DARWIN_UNIX03 */
/*
* Possible values for the third argument to semctl()
*/
#define GETNCNT 3 /* [XSI] Return the value of semncnt {READ} */
#define GETPID 4 /* [XSI] Return the value of sempid {READ} */
#define GETVAL 5 /* [XSI] Return the value of semval {READ} */
#define GETALL 6 /* [XSI] Return semvals into arg.array {READ} */
#define GETZCNT 7 /* [XSI] Return the value of semzcnt {READ} */
#define SETVAL 8 /* [XSI] Set the value of semval to arg.val {ALTER} */
#define SETALL 9 /* [XSI] Set semvals from arg.array {ALTER} */
/* A semaphore; this is an anonymous structure, not for external use */
struct sem {
unsigned short semval; /* semaphore value */
pid_t sempid; /* pid of last operation */
unsigned short semncnt; /* # awaiting semval > cval */
unsigned short semzcnt; /* # awaiting semval == 0 */
};
/*
* Structure of array element for second argument to semop()
*/
struct sembuf {
unsigned short sem_num; /* [XSI] semaphore # */
short sem_op; /* [XSI] semaphore operation */
short sem_flg; /* [XSI] operation flags */
};
/*
* Possible flag values for sem_flg
*/
#define SEM_UNDO 010000 /* [XSI] Set up adjust on exit entry */
#if !defined(_POSIX_C_SOURCE) || defined(_DARWIN_C_SOURCE)
/*
* Union used as the fourth argment to semctl() in all cases. Specific
* member values are used for different values of the third parameter:
*
* Command Member
* ------------------------------------------- ------
* GETALL, SETALL array
* SETVAL val
* IPC_STAT, IPC_SET buf
*
* The union definition is intended to be defined by the user application
* in conforming applications; it is provided here for two reasons:
*
* 1) Historical source compatability for non-conforming applications
* expecting this header to declare the union type on their behalf
*
* 2) Documentation; specifically, 64 bit applications that do not pass
* this structure for 'val', or, alternately, a 64 bit type, will
* not function correctly
*/
union semun {
int val; /* value for SETVAL */
struct semid_ds *buf; /* buffer for IPC_STAT & IPC_SET */
unsigned short *array; /* array for GETALL & SETALL */
};
typedef union semun semun_t;
/*
* Permissions
*/
#define SEM_A 0200 /* alter permission */
#define SEM_R 0400 /* read permission */
#endif /* (!_POSIX_C_SOURCE || _DARWIN_C_SOURCE) */
#ifndef KERNEL
__BEGIN_DECLS
#if !defined(_POSIX_C_SOURCE) || defined(_DARWIN_C_SOURCE)
int semsys(int, ...);
#endif /* (!_POSIX_C_SOURCE || _DARWIN_C_SOURCE) */
int semctl(int, int, int, ...) __DARWIN_ALIAS(semctl);
int semget(key_t, int, int);
int semop(int, struct sembuf *, size_t);
__END_DECLS
#endif /* !KERNEL */
#endif /* !_SEM_H_ */