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      1 /*	$NetBSD: ksem.h,v 1.17 2023/07/11 11:37:29 riastradh Exp $	*/
      2 
      3 /*
      4  * Copyright (c) 2002 Alfred Perlstein <alfred (at) FreeBSD.org>
      5  * All rights reserved.
      6  *
      7  * Redistribution and use in source and binary forms, with or without
      8  * modification, are permitted provided that the following conditions
      9  * are met:
     10  * 1. Redistributions of source code must retain the above copyright
     11  *    notice, this list of conditions and the following disclaimer.
     12  * 2. Redistributions in binary form must reproduce the above copyright
     13  *    notice, this list of conditions and the following disclaimer in the
     14  *    documentation and/or other materials provided with the distribution.
     15  *
     16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
     17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
     20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     26  * SUCH DAMAGE.
     27  */
     28 
     29 #ifndef _SYS_KSEM_H_
     30 #define _SYS_KSEM_H_
     31 
     32 #include <sys/cdefs.h>
     33 
     34 #include <sys/types.h>
     35 
     36 struct timespec;
     37 
     38 #ifdef _KERNEL
     39 
     40 #include <sys/condvar.h>
     41 #include <sys/mutex.h>
     42 #include <sys/queue.h>
     43 
     44 #ifndef _KMEMUSER		/* XXX hack for fstat(8) */
     45 #include <sys/systm.h>
     46 #endif
     47 
     48 struct lwp;
     49 struct proc;
     50 
     51 #define	KSEM_MAX	128
     52 
     53 typedef struct ksem {
     54 	LIST_ENTRY(ksem)	ks_entry;	/* global list entry */
     55 	struct proc *		ks_pshared_proc;/* owner of pshared sem */
     56 	intptr_t		ks_pshared_id;	/* global id for pshared sem */
     57 	kmutex_t		ks_lock;	/* lock on this ksem */
     58 	kcondvar_t		ks_cv;		/* condition variable */
     59 	u_int			ks_pshared_fd;	/* fd in owning proc */
     60 	u_int			ks_ref;		/* number of references */
     61 	u_int			ks_value;	/* current value */
     62 	u_int			ks_waiters;	/* number of waiters */
     63 	char *			ks_name;	/* name, if named */
     64 	size_t			ks_namelen;	/* length of name */
     65 	int			ks_flags;	/* for KS_UNLINKED */
     66 	mode_t			ks_mode;	/* protection bits */
     67 	uid_t			ks_uid;		/* creator uid */
     68 	gid_t			ks_gid;		/* creator gid */
     69 } ksem_t;
     70 
     71 int do_ksem_init(struct lwp *, unsigned int, intptr_t *, copyin_t, copyout_t);
     72 int do_ksem_open(struct lwp *, const char *, int, mode_t, unsigned int,
     73     intptr_t *, copyout_t);
     74 int do_ksem_wait(struct lwp *, intptr_t, bool, struct timespec *);
     75 
     76 extern int	ksem_max;
     77 #endif /* _KERNEL */
     78 
     79 #if defined(_KERNEL) || defined(_LIBC)
     80 #define	KSEM_PSHARED		0x50535244U	/* 'PSRD' */
     81 
     82 #define	KSEM_MARKER_MASK	0xff000001U
     83 #define	KSEM_MARKER_MIN		0x01000001U
     84 #define	KSEM_PSHARED_MARKER	0x70000001U	/* 'p' << 24 | 1 */
     85 #endif /* _KERNEL || _LIBC */
     86 
     87 #ifdef _LIBC
     88 __BEGIN_DECLS
     89 int _ksem_close(intptr_t);
     90 int _ksem_destroy(intptr_t);
     91 int _ksem_getvalue(intptr_t, int *);
     92 int _ksem_init(unsigned int, intptr_t *);
     93 int _ksem_open(const char *, int, mode_t, unsigned int, intptr_t *);
     94 int _ksem_post(intptr_t);
     95 int _ksem_timedwait(intptr_t, const struct timespec * __restrict);
     96 int _ksem_trywait(intptr_t);
     97 int _ksem_unlink(const char *);
     98 int _ksem_wait(intptr_t);
     99 __END_DECLS
    100 #endif /* _LIBC */
    101 
    102 #endif /* _SYS_KSEM_H_ */
    103