xref: /openbsd/sys/dev/wscons/wsevent.c (revision 78b63d65)
1 /* $OpenBSD: wsevent.c,v 1.2 2000/08/01 13:51:18 mickey Exp $ */
2 /* $NetBSD: wsevent.c,v 1.5 2000/03/30 12:45:44 augustss Exp $ */
3 
4 /*
5  * Copyright (c) 1996, 1997 Christopher G. Demetriou.  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. All advertising materials mentioning features or use of this software
16  *    must display the following acknowledgement:
17  *      This product includes software developed by Christopher G. Demetriou
18  *	for the NetBSD Project.
19  * 4. The name of the author may not be used to endorse or promote products
20  *    derived from this software without specific prior written permission
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
23  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
24  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
25  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
26  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
27  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
28  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
29  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
30  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
31  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32  */
33 
34 #include <sys/cdefs.h>
35 
36 /*
37  * Copyright (c) 1992, 1993
38  *	The Regents of the University of California.  All rights reserved.
39  *
40  * This software was developed by the Computer Systems Engineering group
41  * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
42  * contributed to Berkeley.
43  *
44  * All advertising materials mentioning features or use of this software
45  * must display the following acknowledgement:
46  *	This product includes software developed by the University of
47  *	California, Lawrence Berkeley Laboratory.
48  *
49  * Redistribution and use in source and binary forms, with or without
50  * modification, are permitted provided that the following conditions
51  * are met:
52  * 1. Redistributions of source code must retain the above copyright
53  *    notice, this list of conditions and the following disclaimer.
54  * 2. Redistributions in binary form must reproduce the above copyright
55  *    notice, this list of conditions and the following disclaimer in the
56  *    documentation and/or other materials provided with the distribution.
57  * 3. All advertising materials mentioning features or use of this software
58  *    must display the following acknowledgement:
59  *	This product includes software developed by the University of
60  *	California, Berkeley and its contributors.
61  * 4. Neither the name of the University nor the names of its contributors
62  *    may be used to endorse or promote products derived from this software
63  *    without specific prior written permission.
64  *
65  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
66  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
67  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
68  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
69  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
70  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
71  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
72  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
73  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
74  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
75  * SUCH DAMAGE.
76  *
77  *	@(#)event.c	8.1 (Berkeley) 6/11/93
78  */
79 
80 /*
81  * Internal "wscons_event" queue interface for the keyboard and mouse drivers.
82  */
83 
84 #include <sys/param.h>
85 #include <sys/fcntl.h>
86 #include <sys/malloc.h>
87 #include <sys/proc.h>
88 #include <sys/systm.h>
89 #include <sys/vnode.h>
90 #include <sys/select.h>
91 #include <sys/poll.h>
92 
93 #include <dev/wscons/wsconsio.h>
94 #include <dev/wscons/wseventvar.h>
95 
96 /*
97  * Initialize a wscons_event queue.
98  */
99 void
100 wsevent_init(ev)
101 	struct wseventvar *ev;
102 {
103 
104 	ev->get = ev->put = 0;
105 	ev->q = malloc((u_long)WSEVENT_QSIZE * sizeof(struct wscons_event),
106 	    M_DEVBUF, M_WAITOK);
107 	memset((caddr_t)ev->q, 0, WSEVENT_QSIZE * sizeof(struct wscons_event));
108 }
109 
110 /*
111  * Tear down a wscons_event queue.
112  */
113 void
114 wsevent_fini(ev)
115 	struct wseventvar *ev;
116 {
117 
118 	free(ev->q, M_DEVBUF);
119 }
120 
121 /*
122  * User-level interface: read, poll.
123  * (User cannot write an event queue.)
124  */
125 int
126 wsevent_read(ev, uio, flags)
127 	struct wseventvar *ev;
128 	struct uio *uio;
129 	int flags;
130 {
131 	int s, n, cnt, error;
132 
133 	/*
134 	 * Make sure we can return at least 1.
135 	 */
136 	if (uio->uio_resid < sizeof(struct wscons_event))
137 		return (EMSGSIZE);	/* ??? */
138 	s = splwsevent();
139 	while (ev->get == ev->put) {
140 		if (flags & IO_NDELAY) {
141 			splx(s);
142 			return (EWOULDBLOCK);
143 		}
144 		ev->wanted = 1;
145 		error = tsleep((caddr_t)ev, PWSEVENT | PCATCH,
146 		    "wsevent_read", 0);
147 		if (error) {
148 			splx(s);
149 			return (error);
150 		}
151 	}
152 	/*
153 	 * Move wscons_event from tail end of queue (there is at least one
154 	 * there).
155 	 */
156 	if (ev->put < ev->get)
157 		cnt = WSEVENT_QSIZE - ev->get;	/* events in [get..QSIZE) */
158 	else
159 		cnt = ev->put - ev->get;	/* events in [get..put) */
160 	splx(s);
161 	n = howmany(uio->uio_resid, sizeof(struct wscons_event));
162 	if (cnt > n)
163 		cnt = n;
164 	error = uiomove((caddr_t)&ev->q[ev->get],
165 	    cnt * sizeof(struct wscons_event), uio);
166 	n -= cnt;
167 	/*
168 	 * If we do not wrap to 0, used up all our space, or had an error,
169 	 * stop.  Otherwise move from front of queue to put index, if there
170 	 * is anything there to move.
171 	 */
172 	if ((ev->get = (ev->get + cnt) % WSEVENT_QSIZE) != 0 ||
173 	    n == 0 || error || (cnt = ev->put) == 0)
174 		return (error);
175 	if (cnt > n)
176 		cnt = n;
177 	error = uiomove((caddr_t)&ev->q[0],
178 	    cnt * sizeof(struct wscons_event), uio);
179 	ev->get = cnt;
180 	return (error);
181 }
182 
183 int
184 wsevent_poll(ev, events, p)
185 	struct wseventvar *ev;
186 	int events;
187 	struct proc *p;
188 {
189 	int revents = 0;
190 	int s = splwsevent();
191 
192         if (events & (POLLIN | POLLRDNORM)) {
193 		if (ev->get != ev->put)
194 			revents |= events & (POLLIN | POLLRDNORM);
195 		else
196 			selrecord(p, &ev->sel);
197 	}
198 
199 	splx(s);
200 	return (revents);
201 }
202