wsevent.c revision 1.6 1 /* $NetBSD: wsevent.c,v 1.6 2001/10/13 15:56:16 augustss Exp $ */
2
3 /*
4 * Copyright (c) 1996, 1997 Christopher G. Demetriou. All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 * 3. All advertising materials mentioning features or use of this software
15 * must display the following acknowledgement:
16 * This product includes software developed by Christopher G. Demetriou
17 * for the NetBSD Project.
18 * 4. The name of the author may not be used to endorse or promote products
19 * derived from this software without specific prior written permission
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
22 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
23 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
24 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
25 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
26 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
27 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
28 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
29 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
30 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
31 */
32
33 #include <sys/cdefs.h>
34 __KERNEL_RCSID(0, "$NetBSD: wsevent.c,v 1.6 2001/10/13 15:56:16 augustss Exp $");
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(struct wseventvar *ev)
101 {
102
103 ev->get = ev->put = 0;
104 ev->q = malloc((u_long)WSEVENT_QSIZE * sizeof(struct wscons_event),
105 M_DEVBUF, M_WAITOK);
106 memset((caddr_t)ev->q, 0, WSEVENT_QSIZE * sizeof(struct wscons_event));
107 }
108
109 /*
110 * Tear down a wscons_event queue.
111 */
112 void
113 wsevent_fini(struct wseventvar *ev)
114 {
115
116 free(ev->q, M_DEVBUF);
117 }
118
119 /*
120 * User-level interface: read, poll.
121 * (User cannot write an event queue.)
122 */
123 int
124 wsevent_read(struct wseventvar *ev, struct uio *uio, int flags)
125 {
126 int s, n, cnt, error;
127
128 /*
129 * Make sure we can return at least 1.
130 */
131 if (uio->uio_resid < sizeof(struct wscons_event))
132 return (EMSGSIZE); /* ??? */
133 s = splwsevent();
134 while (ev->get == ev->put) {
135 if (flags & IO_NDELAY) {
136 splx(s);
137 return (EWOULDBLOCK);
138 }
139 ev->wanted = 1;
140 error = tsleep((caddr_t)ev, PWSEVENT | PCATCH,
141 "wsevent_read", 0);
142 if (error) {
143 splx(s);
144 return (error);
145 }
146 }
147 /*
148 * Move wscons_event from tail end of queue (there is at least one
149 * there).
150 */
151 if (ev->put < ev->get)
152 cnt = WSEVENT_QSIZE - ev->get; /* events in [get..QSIZE) */
153 else
154 cnt = ev->put - ev->get; /* events in [get..put) */
155 splx(s);
156 n = howmany(uio->uio_resid, sizeof(struct wscons_event));
157 if (cnt > n)
158 cnt = n;
159 error = uiomove((caddr_t)&ev->q[ev->get],
160 cnt * sizeof(struct wscons_event), uio);
161 n -= cnt;
162 /*
163 * If we do not wrap to 0, used up all our space, or had an error,
164 * stop. Otherwise move from front of queue to put index, if there
165 * is anything there to move.
166 */
167 if ((ev->get = (ev->get + cnt) % WSEVENT_QSIZE) != 0 ||
168 n == 0 || error || (cnt = ev->put) == 0)
169 return (error);
170 if (cnt > n)
171 cnt = n;
172 error = uiomove((caddr_t)&ev->q[0],
173 cnt * sizeof(struct wscons_event), uio);
174 ev->get = cnt;
175 return (error);
176 }
177
178 int
179 wsevent_poll(struct wseventvar *ev, int events, struct proc *p)
180 {
181 int revents = 0;
182 int s = splwsevent();
183
184 if (events & (POLLIN | POLLRDNORM)) {
185 if (ev->get != ev->put)
186 revents |= events & (POLLIN | POLLRDNORM);
187 else
188 selrecord(p, &ev->sel);
189 }
190
191 splx(s);
192 return (revents);
193 }
194