1 /* $NetBSD: wsevent.c,v 1.12 2002/11/26 18:49:50 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. All advertising materials mentioning features or use of this software 55 * must display the following acknowledgement: 56 * This product includes software developed by the University of 57 * California, Berkeley and its contributors. 58 * 4. Neither the name of the University nor the names of its contributors 59 * may be used to endorse or promote products derived from this software 60 * without specific prior written permission. 61 * 62 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 63 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 64 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 65 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 66 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 67 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 68 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 69 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 70 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 71 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 72 * SUCH DAMAGE. 73 * 74 * @(#)event.c 8.1 (Berkeley) 6/11/93 75 */ 76 77 /* 78 * Internal "wscons_event" queue interface for the keyboard and mouse drivers. 79 */ 80 81 #include <sys/cdefs.h> 82 __KERNEL_RCSID(0, "$NetBSD: wsevent.c,v 1.12 2002/11/26 18:49:50 christos Exp $"); 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 #ifdef DIAGNOSTIC 104 if (ev->q != NULL) { 105 printf("wsevent_init: already init\n"); 106 return; 107 } 108 #endif 109 ev->get = ev->put = 0; 110 ev->q = malloc((u_long)WSEVENT_QSIZE * sizeof(struct wscons_event), 111 M_DEVBUF, M_WAITOK|M_ZERO); 112 } 113 114 /* 115 * Tear down a wscons_event queue. 116 */ 117 void 118 wsevent_fini(struct wseventvar *ev) 119 { 120 121 free(ev->q, M_DEVBUF); 122 ev->q = NULL; 123 } 124 125 /* 126 * User-level interface: read, poll. 127 * (User cannot write an event queue.) 128 */ 129 int 130 wsevent_read(struct wseventvar *ev, struct uio *uio, int flags) 131 { 132 int s, n, cnt, error; 133 134 /* 135 * Make sure we can return at least 1. 136 */ 137 if (uio->uio_resid < sizeof(struct wscons_event)) 138 return (EMSGSIZE); /* ??? */ 139 s = splwsevent(); 140 while (ev->get == ev->put) { 141 if (flags & IO_NDELAY) { 142 splx(s); 143 return (EWOULDBLOCK); 144 } 145 ev->wanted = 1; 146 error = tsleep(ev, PWSEVENT | PCATCH, 147 "wsevent_read", 0); 148 if (error) { 149 splx(s); 150 return (error); 151 } 152 } 153 /* 154 * Move wscons_event from tail end of queue (there is at least one 155 * there). 156 */ 157 if (ev->put < ev->get) 158 cnt = WSEVENT_QSIZE - ev->get; /* events in [get..QSIZE) */ 159 else 160 cnt = ev->put - ev->get; /* events in [get..put) */ 161 splx(s); 162 n = howmany(uio->uio_resid, sizeof(struct wscons_event)); 163 if (cnt > n) 164 cnt = n; 165 error = uiomove(&ev->q[ev->get], 166 cnt * sizeof(struct wscons_event), uio); 167 n -= cnt; 168 /* 169 * If we do not wrap to 0, used up all our space, or had an error, 170 * stop. Otherwise move from front of queue to put index, if there 171 * is anything there to move. 172 */ 173 if ((ev->get = (ev->get + cnt) % WSEVENT_QSIZE) != 0 || 174 n == 0 || error || (cnt = ev->put) == 0) 175 return (error); 176 if (cnt > n) 177 cnt = n; 178 error = uiomove(&ev->q[0], 179 cnt * sizeof(struct wscons_event), uio); 180 ev->get = cnt; 181 return (error); 182 } 183 184 int 185 wsevent_poll(struct wseventvar *ev, int events, struct proc *p) 186 { 187 int revents = 0; 188 int s = splwsevent(); 189 190 if (events & (POLLIN | POLLRDNORM)) { 191 if (ev->get != ev->put) 192 revents |= events & (POLLIN | POLLRDNORM); 193 else 194 selrecord(p, &ev->sel); 195 } 196 197 splx(s); 198 return (revents); 199 } 200 201 static void 202 filt_wseventrdetach(struct knote *kn) 203 { 204 struct wseventvar *ev = kn->kn_hook; 205 int s; 206 207 s = splwsevent(); 208 SLIST_REMOVE(&ev->sel.sel_klist, kn, knote, kn_selnext); 209 splx(s); 210 } 211 212 static int 213 filt_wseventread(struct knote *kn, long hint) 214 { 215 struct wseventvar *ev = kn->kn_hook; 216 217 if (ev->get == ev->put) 218 return (0); 219 220 if (ev->get < ev->put) 221 kn->kn_data = ev->put - ev->get; 222 else 223 kn->kn_data = (WSEVENT_QSIZE - ev->get) + 224 ev->put; 225 226 kn->kn_data *= sizeof(struct wscons_event); 227 228 return (1); 229 } 230 231 static const struct filterops wsevent_filtops = 232 { 1, NULL, filt_wseventrdetach, filt_wseventread }; 233 234 int 235 wsevent_kqfilter(struct wseventvar *ev, struct knote *kn) 236 { 237 struct klist *klist; 238 int s; 239 240 switch (kn->kn_filter) { 241 case EVFILT_READ: 242 klist = &ev->sel.sel_klist; 243 kn->kn_fop = &wsevent_filtops; 244 break; 245 246 default: 247 return (1); 248 } 249 250 kn->kn_hook = ev; 251 252 s = splwsevent(); 253 SLIST_INSERT_HEAD(klist, kn, kn_selnext); 254 splx(s); 255 256 return (0); 257 } 258