xref: /openbsd/sys/sys/sigio.h (revision 36b1b8b4)
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 
38 struct sigio;
39 LIST_HEAD(sigiolst, sigio);
40 
41 /*
42  * sigio registration
43  *
44  * Locking:
45  *	S	sigio_lock
46  */
47 struct 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  */
64 struct 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 
81 static inline void
sigio_init(struct sigio_ref * sir)82 sigio_init(struct sigio_ref *sir)
83 {
84 	sir->sir_sigio = NULL;
85 }
86 
87 void	sigio_copy(struct sigio_ref *, struct sigio_ref *);
88 void	sigio_free(struct sigio_ref *);
89 void	sigio_freelist(struct sigiolst *);
90 void	sigio_getown(struct sigio_ref *, u_long, caddr_t);
91 int	sigio_setown(struct sigio_ref *, u_long, caddr_t);
92 
93 #endif /* _KERNEL */
94 
95 #endif /* _SYS_SIGIO_H_ */
96