1 /* $NetBSD: event.c,v 1.7 2002/11/26 19:50:30 christos 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/param.h> 52 #include <sys/fcntl.h> 53 #include <sys/malloc.h> 54 #include <sys/proc.h> 55 #include <sys/systm.h> 56 #include <sys/vnode.h> 57 #include <sys/select.h> 58 #include <sys/poll.h> 59 60 #include <machine/vuid_event.h> 61 #include <x68k/dev/event_var.h> 62 63 /* 64 * Initialize a firm_event queue. 65 */ 66 void 67 ev_init(ev) 68 register struct evvar *ev; 69 { 70 71 ev->ev_get = ev->ev_put = 0; 72 ev->ev_q = malloc((u_long)EV_QSIZE * sizeof(struct firm_event), 73 M_DEVBUF, M_WAITOK); 74 memset((caddr_t)ev->ev_q, 0, EV_QSIZE * sizeof(struct firm_event)); 75 } 76 77 /* 78 * Tear down a firm_event queue. 79 */ 80 void 81 ev_fini(ev) 82 register struct evvar *ev; 83 { 84 85 free(ev->ev_q, M_DEVBUF); 86 } 87 88 /* 89 * User-level interface: read, select. 90 * (User cannot write an event queue.) 91 */ 92 int 93 ev_read(ev, uio, flags) 94 register struct evvar *ev; 95 struct uio *uio; 96 int flags; 97 { 98 int s, n, cnt, error; 99 100 /* 101 * Make sure we can return at least 1. 102 */ 103 if (uio->uio_resid < sizeof(struct firm_event)) 104 return (EMSGSIZE); /* ??? */ 105 s = splev(); 106 while (ev->ev_get == ev->ev_put) { 107 if (flags & IO_NDELAY) { 108 splx(s); 109 return (EWOULDBLOCK); 110 } 111 ev->ev_wanted = 1; 112 error = tsleep((caddr_t)ev, PEVENT | PCATCH, "firm_event", 0); 113 if (error) { 114 splx(s); 115 return (error); 116 } 117 } 118 /* 119 * Move firm_events from tail end of queue (there is at least one 120 * there). 121 */ 122 if (ev->ev_put < ev->ev_get) 123 cnt = EV_QSIZE - ev->ev_get; /* events in [get..QSIZE) */ 124 else 125 cnt = ev->ev_put - ev->ev_get; /* events in [get..put) */ 126 splx(s); 127 n = howmany(uio->uio_resid, sizeof(struct firm_event)); 128 if (cnt > n) 129 cnt = n; 130 error = uiomove((caddr_t)&ev->ev_q[ev->ev_get], 131 cnt * sizeof(struct firm_event), uio); 132 n -= cnt; 133 /* 134 * If we do not wrap to 0, used up all our space, or had an error, 135 * stop. Otherwise move from front of queue to put index, if there 136 * is anything there to move. 137 */ 138 if ((ev->ev_get = (ev->ev_get + cnt) % EV_QSIZE) != 0 || 139 n == 0 || error || (cnt = ev->ev_put) == 0) 140 return (error); 141 if (cnt > n) 142 cnt = n; 143 error = uiomove((caddr_t)&ev->ev_q[0], 144 cnt * sizeof(struct firm_event), uio); 145 ev->ev_get = cnt; 146 return (error); 147 } 148 149 int 150 ev_poll(ev, events, p) 151 register struct evvar *ev; 152 int events; 153 struct proc *p; 154 { 155 int s = splev(), revents = 0; 156 157 if (events & (POLLIN | POLLRDNORM)) { 158 if (ev->ev_get == ev->ev_put) 159 selrecord(p, &ev->ev_sel); 160 else 161 revents |= events & (POLLIN | POLLRDNORM); 162 } 163 revents |= events & (POLLOUT | POLLWRNORM); 164 165 splx(s); 166 return (revents); 167 } 168 169 static void 170 filt_evrdetach(struct knote *kn) 171 { 172 struct evvar *ev = kn->kn_hook; 173 int s; 174 175 s = splev(); 176 SLIST_REMOVE(&ev->ev_sel.sel_klist, kn, knote, kn_selnext); 177 splx(s); 178 } 179 180 static int 181 filt_evread(struct knote *kn, long hint) 182 { 183 struct evvar *ev = kn->kn_hook; 184 185 if (ev->ev_get == ev->ev_put) 186 return (0); 187 188 if (ev->ev_get < ev->ev_put) 189 kn->kn_data = ev->ev_put - ev->ev_get; 190 else 191 kn->kn_data = (EV_QSIZE - ev->ev_get) + 192 ev->ev_put; 193 194 kn->kn_data *= sizeof(struct firm_event); 195 196 return (1); 197 } 198 199 static const struct filterops ev_filtops = 200 { 1, NULL, filt_evrdetach, filt_evread }; 201 202 int 203 ev_kqfilter(struct evvar *ev, struct knote *kn) 204 { 205 struct klist *klist; 206 int s; 207 208 switch (kn->kn_filter) { 209 case EVFILT_READ: 210 klist = &ev->ev_sel.sel_klist; 211 kn->kn_fop = &ev_filtops; 212 break; 213 214 default: 215 return (1); 216 } 217 218 kn->kn_hook = ev; 219 220 s = splev(); 221 SLIST_INSERT_HEAD(klist, kn, kn_selnext); 222 splx(s); 223 224 return (0); 225 } 226