1/*-
2 * SPDX-License-Identifier: BSD-3-Clause
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
32#ifndef _SYS_SIGIO_H_
33#define _SYS_SIGIO_H_
34
35/*
36 * This structure holds the information needed to send a SIGIO or
37 * a SIGURG signal to a process or process group when new data arrives
38 * on a device or socket.  The structure is placed on an SLIST belonging
39 * to the proc or pgrp so that the entire list may be revoked when the
40 * process exits or the process group disappears.
41 *
42 * (c)	const
43 * (pg)	locked by either the process or process group lock
44 */
45struct sigio {
46	union {
47		struct	proc *siu_proc; /* (c)	process to receive SIGIO/SIGURG */
48		struct	pgrp *siu_pgrp; /* (c)	process group to receive ... */
49	} sio_u;
50	SLIST_ENTRY(sigio) sio_pgsigio;	/* (pg)	sigio's for process or group */
51	struct	sigio **sio_myref;	/* (c)	location of the pointer that holds
52					 * 	the reference to this structure */
53	struct	ucred *sio_ucred;	/* (c)	current credentials */
54	pid_t	sio_pgid;		/* (c)	pgid for signals */
55};
56#define	sio_proc	sio_u.siu_proc
57#define	sio_pgrp	sio_u.siu_pgrp
58
59SLIST_HEAD(sigiolst, sigio);
60
61pid_t	fgetown(struct sigio **sigiop);
62int	fsetown(pid_t pgid, struct sigio **sigiop);
63void	funsetown(struct sigio **sigiop);
64void	funsetownlst(struct sigiolst *sigiolst);
65
66#endif /* _SYS_SIGIO_H_ */
67