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