1 /* $NetBSD: event.c,v 1.8 2003/07/15 01:44:51 lukem Exp $ */ 2 3 /* 4 * Copyright (c) 1992, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * This software was developed by the Computer Systems Engineering group 8 * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and 9 * contributed to Berkeley. 10 * 11 * All advertising materials mentioning features or use of this software 12 * must display the following acknowledgement: 13 * This product includes software developed by the University of 14 * California, Lawrence Berkeley Laboratory. 15 * 16 * Redistribution and use in source and binary forms, with or without 17 * modification, are permitted provided that the following conditions 18 * are met: 19 * 1. Redistributions of source code must retain the above copyright 20 * notice, this list of conditions and the following disclaimer. 21 * 2. Redistributions in binary form must reproduce the above copyright 22 * notice, this list of conditions and the following disclaimer in the 23 * documentation and/or other materials provided with the distribution. 24 * 3. All advertising materials mentioning features or use of this software 25 * must display the following acknowledgement: 26 * This product includes software developed by the University of 27 * California, Berkeley and its contributors. 28 * 4. Neither the name of the University nor the names of its contributors 29 * may be used to endorse or promote products derived from this software 30 * without specific prior written permission. 31 * 32 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 33 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 34 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 35 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 36 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 37 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 38 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 39 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 40 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 41 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 42 * SUCH DAMAGE. 43 * 44 * @(#)event.c 8.1 (Berkeley) 6/11/93 45 */ 46 47 /* 48 * Internal `Firm_event' interface for the keyboard and mouse drivers. 49 */ 50 51 #include <sys/cdefs.h> 52 __KERNEL_RCSID(0, "$NetBSD: event.c,v 1.8 2003/07/15 01:44:51 lukem Exp $"); 53 54 #include <sys/param.h> 55 #include <sys/fcntl.h> 56 #include <sys/malloc.h> 57 #include <sys/proc.h> 58 #include <sys/systm.h> 59 #include <sys/vnode.h> 60 #include <sys/select.h> 61 #include <sys/poll.h> 62 63 #include <machine/vuid_event.h> 64 #include <x68k/dev/event_var.h> 65 66 /* 67 * Initialize a firm_event queue. 68 */ 69 void 70 ev_init(ev) 71 register struct evvar *ev; 72 { 73 74 ev->ev_get = ev->ev_put = 0; 75 ev->ev_q = malloc((u_long)EV_QSIZE * sizeof(struct firm_event), 76 M_DEVBUF, M_WAITOK); 77 memset((caddr_t)ev->ev_q, 0, EV_QSIZE * sizeof(struct firm_event)); 78 } 79 80 /* 81 * Tear down a firm_event queue. 82 */ 83 void 84 ev_fini(ev) 85 register struct evvar *ev; 86 { 87 88 free(ev->ev_q, M_DEVBUF); 89 } 90 91 /* 92 * User-level interface: read, select. 93 * (User cannot write an event queue.) 94 */ 95 int 96 ev_read(ev, uio, flags) 97 register struct evvar *ev; 98 struct uio *uio; 99 int flags; 100 { 101 int s, n, cnt, error; 102 103 /* 104 * Make sure we can return at least 1. 105 */ 106 if (uio->uio_resid < sizeof(struct firm_event)) 107 return (EMSGSIZE); /* ??? */ 108 s = splev(); 109 while (ev->ev_get == ev->ev_put) { 110 if (flags & IO_NDELAY) { 111 splx(s); 112 return (EWOULDBLOCK); 113 } 114 ev->ev_wanted = 1; 115 error = tsleep((caddr_t)ev, PEVENT | PCATCH, "firm_event", 0); 116 if (error) { 117 splx(s); 118 return (error); 119 } 120 } 121 /* 122 * Move firm_events from tail end of queue (there is at least one 123 * there). 124 */ 125 if (ev->ev_put < ev->ev_get) 126 cnt = EV_QSIZE - ev->ev_get; /* events in [get..QSIZE) */ 127 else 128 cnt = ev->ev_put - ev->ev_get; /* events in [get..put) */ 129 splx(s); 130 n = howmany(uio->uio_resid, sizeof(struct firm_event)); 131 if (cnt > n) 132 cnt = n; 133 error = uiomove((caddr_t)&ev->ev_q[ev->ev_get], 134 cnt * sizeof(struct firm_event), uio); 135 n -= cnt; 136 /* 137 * If we do not wrap to 0, used up all our space, or had an error, 138 * stop. Otherwise move from front of queue to put index, if there 139 * is anything there to move. 140 */ 141 if ((ev->ev_get = (ev->ev_get + cnt) % EV_QSIZE) != 0 || 142 n == 0 || error || (cnt = ev->ev_put) == 0) 143 return (error); 144 if (cnt > n) 145 cnt = n; 146 error = uiomove((caddr_t)&ev->ev_q[0], 147 cnt * sizeof(struct firm_event), uio); 148 ev->ev_get = cnt; 149 return (error); 150 } 151 152 int 153 ev_poll(ev, events, p) 154 register struct evvar *ev; 155 int events; 156 struct proc *p; 157 { 158 int s = splev(), revents = 0; 159 160 if (events & (POLLIN | POLLRDNORM)) { 161 if (ev->ev_get == ev->ev_put) 162 selrecord(p, &ev->ev_sel); 163 else 164 revents |= events & (POLLIN | POLLRDNORM); 165 } 166 revents |= events & (POLLOUT | POLLWRNORM); 167 168 splx(s); 169 return (revents); 170 } 171 172 static void 173 filt_evrdetach(struct knote *kn) 174 { 175 struct evvar *ev = kn->kn_hook; 176 int s; 177 178 s = splev(); 179 SLIST_REMOVE(&ev->ev_sel.sel_klist, kn, knote, kn_selnext); 180 splx(s); 181 } 182 183 static int 184 filt_evread(struct knote *kn, long hint) 185 { 186 struct evvar *ev = kn->kn_hook; 187 188 if (ev->ev_get == ev->ev_put) 189 return (0); 190 191 if (ev->ev_get < ev->ev_put) 192 kn->kn_data = ev->ev_put - ev->ev_get; 193 else 194 kn->kn_data = (EV_QSIZE - ev->ev_get) + 195 ev->ev_put; 196 197 kn->kn_data *= sizeof(struct firm_event); 198 199 return (1); 200 } 201 202 static const struct filterops ev_filtops = 203 { 1, NULL, filt_evrdetach, filt_evread }; 204 205 int 206 ev_kqfilter(struct evvar *ev, struct knote *kn) 207 { 208 struct klist *klist; 209 int s; 210 211 switch (kn->kn_filter) { 212 case EVFILT_READ: 213 klist = &ev->ev_sel.sel_klist; 214 kn->kn_fop = &ev_filtops; 215 break; 216 217 default: 218 return (1); 219 } 220 221 kn->kn_hook = ev; 222 223 s = splev(); 224 SLIST_INSERT_HEAD(klist, kn, kn_selnext); 225 splx(s); 226 227 return (0); 228 } 229