xref: /netbsd-src/sys/dev/wscons/wsevent.c (revision aaf4ece63a859a04e37cf3a7229b5fab0157cc06)
1 /* $NetBSD: wsevent.c,v 1.17 2005/12/11 12:24:12 christos 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 /*
34  * Copyright (c) 1992, 1993
35  *	The Regents of the University of California.  All rights reserved.
36  *
37  * This software was developed by the Computer Systems Engineering group
38  * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
39  * contributed to Berkeley.
40  *
41  * All advertising materials mentioning features or use of this software
42  * must display the following acknowledgement:
43  *	This product includes software developed by the University of
44  *	California, Lawrence Berkeley Laboratory.
45  *
46  * Redistribution and use in source and binary forms, with or without
47  * modification, are permitted provided that the following conditions
48  * are met:
49  * 1. Redistributions of source code must retain the above copyright
50  *    notice, this list of conditions and the following disclaimer.
51  * 2. Redistributions in binary form must reproduce the above copyright
52  *    notice, this list of conditions and the following disclaimer in the
53  *    documentation and/or other materials provided with the distribution.
54  * 3. Neither the name of the University nor the names of its contributors
55  *    may be used to endorse or promote products derived from this software
56  *    without specific prior written permission.
57  *
58  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
59  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
60  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
61  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
62  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
63  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
64  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
65  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
66  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
67  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
68  * SUCH DAMAGE.
69  *
70  *	@(#)event.c	8.1 (Berkeley) 6/11/93
71  */
72 
73 /*
74  * Internal "wscons_event" queue interface for the keyboard and mouse drivers.
75  */
76 
77 #include <sys/cdefs.h>
78 __KERNEL_RCSID(0, "$NetBSD: wsevent.c,v 1.17 2005/12/11 12:24:12 christos Exp $");
79 
80 #include <sys/param.h>
81 #include <sys/fcntl.h>
82 #include <sys/malloc.h>
83 #include <sys/proc.h>
84 #include <sys/systm.h>
85 #include <sys/vnode.h>
86 #include <sys/select.h>
87 #include <sys/poll.h>
88 
89 #include <dev/wscons/wsconsio.h>
90 #include <dev/wscons/wseventvar.h>
91 
92 /*
93  * Initialize a wscons_event queue.
94  */
95 void
96 wsevent_init(struct wseventvar *ev)
97 {
98 
99 	if (ev->q != NULL) {
100 #ifdef DIAGNOSTIC
101 		printf("wsevent_init: already init\n");
102 #endif
103 		return;
104 	}
105 	ev->get = ev->put = 0;
106 	ev->q = malloc((u_long)WSEVENT_QSIZE * sizeof(struct wscons_event),
107 		       M_DEVBUF, M_WAITOK|M_ZERO);
108 }
109 
110 /*
111  * Tear down a wscons_event queue.
112  */
113 void
114 wsevent_fini(struct wseventvar *ev)
115 {
116 	if (ev->q == NULL) {
117 #ifdef DIAGNOSTIC
118 		printf("wsevent_fini: already fini\n");
119 #endif
120 		return;
121 	}
122 	free(ev->q, M_DEVBUF);
123 	ev->q = NULL;
124 }
125 
126 /*
127  * User-level interface: read, poll.
128  * (User cannot write an event queue.)
129  */
130 int
131 wsevent_read(struct wseventvar *ev, struct uio *uio, int flags)
132 {
133 	int s, n, cnt, error;
134 
135 	/*
136 	 * Make sure we can return at least 1.
137 	 */
138 	if (uio->uio_resid < sizeof(struct wscons_event))
139 		return (EMSGSIZE);	/* ??? */
140 	s = splwsevent();
141 	while (ev->get == ev->put) {
142 		if (flags & IO_NDELAY) {
143 			splx(s);
144 			return (EWOULDBLOCK);
145 		}
146 		ev->wanted = 1;
147 		error = tsleep(ev, PWSEVENT | PCATCH,
148 		    "wsevent_read", 0);
149 		if (error) {
150 			splx(s);
151 			return (error);
152 		}
153 	}
154 	/*
155 	 * Move wscons_event from tail end of queue (there is at least one
156 	 * there).
157 	 */
158 	if (ev->put < ev->get)
159 		cnt = WSEVENT_QSIZE - ev->get;	/* events in [get..QSIZE) */
160 	else
161 		cnt = ev->put - ev->get;	/* events in [get..put) */
162 	splx(s);
163 	n = howmany(uio->uio_resid, sizeof(struct wscons_event));
164 	if (cnt > n)
165 		cnt = n;
166 	error = uiomove(&ev->q[ev->get],
167 	    cnt * sizeof(struct wscons_event), uio);
168 	n -= cnt;
169 	/*
170 	 * If we do not wrap to 0, used up all our space, or had an error,
171 	 * stop.  Otherwise move from front of queue to put index, if there
172 	 * is anything there to move.
173 	 */
174 	if ((ev->get = (ev->get + cnt) % WSEVENT_QSIZE) != 0 ||
175 	    n == 0 || error || (cnt = ev->put) == 0)
176 		return (error);
177 	if (cnt > n)
178 		cnt = n;
179 	error = uiomove(&ev->q[0],
180 	    cnt * sizeof(struct wscons_event), uio);
181 	ev->get = cnt;
182 	return (error);
183 }
184 
185 int
186 wsevent_poll(struct wseventvar *ev, int events, struct lwp *l)
187 {
188 	int revents = 0;
189 	int s = splwsevent();
190 
191         if (events & (POLLIN | POLLRDNORM)) {
192 		if (ev->get != ev->put)
193 			revents |= events & (POLLIN | POLLRDNORM);
194 		else
195 			selrecord(l, &ev->sel);
196 	}
197 
198 	splx(s);
199 	return (revents);
200 }
201 
202 static void
203 filt_wseventrdetach(struct knote *kn)
204 {
205 	struct wseventvar *ev = kn->kn_hook;
206 	int s;
207 
208 	s = splwsevent();
209 	SLIST_REMOVE(&ev->sel.sel_klist, kn, knote, kn_selnext);
210 	splx(s);
211 }
212 
213 static int
214 filt_wseventread(struct knote *kn, long hint)
215 {
216 	struct wseventvar *ev = kn->kn_hook;
217 
218 	if (ev->get == ev->put)
219 		return (0);
220 
221 	if (ev->get < ev->put)
222 		kn->kn_data = ev->put - ev->get;
223 	else
224 		kn->kn_data = (WSEVENT_QSIZE - ev->get) +
225 		    ev->put;
226 
227 	kn->kn_data *= sizeof(struct wscons_event);
228 
229 	return (1);
230 }
231 
232 static const struct filterops wsevent_filtops =
233 	{ 1, NULL, filt_wseventrdetach, filt_wseventread };
234 
235 int
236 wsevent_kqfilter(struct wseventvar *ev, struct knote *kn)
237 {
238 	struct klist *klist;
239 	int s;
240 
241 	switch (kn->kn_filter) {
242 	case EVFILT_READ:
243 		klist = &ev->sel.sel_klist;
244 		kn->kn_fop = &wsevent_filtops;
245 		break;
246 
247 	default:
248 		return (1);
249 	}
250 
251 	kn->kn_hook = ev;
252 
253 	s = splwsevent();
254 	SLIST_INSERT_HEAD(klist, kn, kn_selnext);
255 	splx(s);
256 
257 	return (0);
258 }
259