1/*	$OpenBSD: sigio.h,v 1.4 2020/01/08 16:27:42 visa Exp $	*/
2
3/*-
4 * Copyright (c) 1990, 1993
5 *	The Regents of the University of California.  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 * 3. Neither the name of the University nor the names of its contributors
16 *    may be used to endorse or promote products derived from this software
17 *    without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 *
31 *	@(#)filedesc.h	8.1 (Berkeley) 6/2/93
32 * $FreeBSD: head/sys/sys/sigio.h 326023 2017-11-20 19:43:44Z pfg $
33 */
34
35#ifndef _SYS_SIGIO_H_
36#define _SYS_SIGIO_H_
37
38struct sigio;
39LIST_HEAD(sigiolst, sigio);
40
41/*
42 * sigio registration
43 *
44 * Locking:
45 *	S	sigio_lock
46 */
47struct sigio_ref {
48	struct sigio	*sir_sigio;	/* [S] associated sigio struct */
49};
50
51#ifdef _KERNEL
52
53/*
54 * This structure holds the information needed to send a SIGIO or
55 * a SIGURG signal to a process or process group when new data arrives
56 * on a device or socket.  The structure is placed on an LIST belonging
57 * to the proc or pgrp so that the entire list may be revoked when the
58 * process exits or the process group disappears.
59 *
60 * Locking:
61 *	I	immutable after creation
62 *	S	sigio_lock
63 */
64struct sigio {
65	union {
66		struct	process *siu_proc;
67					/* [I] process to receive
68					 *     SIGIO/SIGURG */
69		struct	pgrp *siu_pgrp; /* [I] process group to receive ... */
70	} sio_u;
71	LIST_ENTRY(sigio) sio_pgsigio;	/* [S] sigio's for process or group */
72	struct	sigio_ref *sio_myref;	/* [I] location of the pointer that
73					 *     holds the reference to
74					 *     this structure */
75	struct	ucred *sio_ucred;	/* [I] current credentials */
76	pid_t	sio_pgid;		/* [I] pgid for signals */
77};
78#define	sio_proc	sio_u.siu_proc
79#define	sio_pgrp	sio_u.siu_pgrp
80
81static inline void
82sigio_init(struct sigio_ref *sir)
83{
84	sir->sir_sigio = NULL;
85}
86
87void	sigio_copy(struct sigio_ref *, struct sigio_ref *);
88void	sigio_free(struct sigio_ref *);
89void	sigio_freelist(struct sigiolst *);
90void	sigio_getown(struct sigio_ref *, u_long, caddr_t);
91int	sigio_setown(struct sigio_ref *, u_long, caddr_t);
92
93#endif /* _KERNEL */
94
95#endif /* _SYS_SIGIO_H_ */
96