1 /* $NetBSD: event.c,v 1.9 2003/08/07 16:30:22 agc 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. Neither the name of the University nor the names of its contributors 25 * may be used to endorse or promote products derived from this software 26 * without specific prior written permission. 27 * 28 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 29 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 30 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 31 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 32 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 33 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 34 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 35 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 36 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 37 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 38 * SUCH DAMAGE. 39 * 40 * @(#)event.c 8.1 (Berkeley) 6/11/93 41 */ 42 43 /* 44 * Internal `Firm_event' interface for the keyboard and mouse drivers. 45 */ 46 47 #include <sys/cdefs.h> 48 __KERNEL_RCSID(0, "$NetBSD: event.c,v 1.9 2003/08/07 16:30:22 agc Exp $"); 49 50 #include <sys/param.h> 51 #include <sys/fcntl.h> 52 #include <sys/malloc.h> 53 #include <sys/proc.h> 54 #include <sys/systm.h> 55 #include <sys/vnode.h> 56 #include <sys/select.h> 57 #include <sys/poll.h> 58 59 #include <machine/vuid_event.h> 60 #include <x68k/dev/event_var.h> 61 62 /* 63 * Initialize a firm_event queue. 64 */ 65 void 66 ev_init(ev) 67 register struct evvar *ev; 68 { 69 70 ev->ev_get = ev->ev_put = 0; 71 ev->ev_q = malloc((u_long)EV_QSIZE * sizeof(struct firm_event), 72 M_DEVBUF, M_WAITOK); 73 memset((caddr_t)ev->ev_q, 0, EV_QSIZE * sizeof(struct firm_event)); 74 } 75 76 /* 77 * Tear down a firm_event queue. 78 */ 79 void 80 ev_fini(ev) 81 register struct evvar *ev; 82 { 83 84 free(ev->ev_q, M_DEVBUF); 85 } 86 87 /* 88 * User-level interface: read, select. 89 * (User cannot write an event queue.) 90 */ 91 int 92 ev_read(ev, uio, flags) 93 register struct evvar *ev; 94 struct uio *uio; 95 int flags; 96 { 97 int s, n, cnt, error; 98 99 /* 100 * Make sure we can return at least 1. 101 */ 102 if (uio->uio_resid < sizeof(struct firm_event)) 103 return (EMSGSIZE); /* ??? */ 104 s = splev(); 105 while (ev->ev_get == ev->ev_put) { 106 if (flags & IO_NDELAY) { 107 splx(s); 108 return (EWOULDBLOCK); 109 } 110 ev->ev_wanted = 1; 111 error = tsleep((caddr_t)ev, PEVENT | PCATCH, "firm_event", 0); 112 if (error) { 113 splx(s); 114 return (error); 115 } 116 } 117 /* 118 * Move firm_events from tail end of queue (there is at least one 119 * there). 120 */ 121 if (ev->ev_put < ev->ev_get) 122 cnt = EV_QSIZE - ev->ev_get; /* events in [get..QSIZE) */ 123 else 124 cnt = ev->ev_put - ev->ev_get; /* events in [get..put) */ 125 splx(s); 126 n = howmany(uio->uio_resid, sizeof(struct firm_event)); 127 if (cnt > n) 128 cnt = n; 129 error = uiomove((caddr_t)&ev->ev_q[ev->ev_get], 130 cnt * sizeof(struct firm_event), uio); 131 n -= cnt; 132 /* 133 * If we do not wrap to 0, used up all our space, or had an error, 134 * stop. Otherwise move from front of queue to put index, if there 135 * is anything there to move. 136 */ 137 if ((ev->ev_get = (ev->ev_get + cnt) % EV_QSIZE) != 0 || 138 n == 0 || error || (cnt = ev->ev_put) == 0) 139 return (error); 140 if (cnt > n) 141 cnt = n; 142 error = uiomove((caddr_t)&ev->ev_q[0], 143 cnt * sizeof(struct firm_event), uio); 144 ev->ev_get = cnt; 145 return (error); 146 } 147 148 int 149 ev_poll(ev, events, p) 150 register struct evvar *ev; 151 int events; 152 struct proc *p; 153 { 154 int s = splev(), revents = 0; 155 156 if (events & (POLLIN | POLLRDNORM)) { 157 if (ev->ev_get == ev->ev_put) 158 selrecord(p, &ev->ev_sel); 159 else 160 revents |= events & (POLLIN | POLLRDNORM); 161 } 162 revents |= events & (POLLOUT | POLLWRNORM); 163 164 splx(s); 165 return (revents); 166 } 167 168 static void 169 filt_evrdetach(struct knote *kn) 170 { 171 struct evvar *ev = kn->kn_hook; 172 int s; 173 174 s = splev(); 175 SLIST_REMOVE(&ev->ev_sel.sel_klist, kn, knote, kn_selnext); 176 splx(s); 177 } 178 179 static int 180 filt_evread(struct knote *kn, long hint) 181 { 182 struct evvar *ev = kn->kn_hook; 183 184 if (ev->ev_get == ev->ev_put) 185 return (0); 186 187 if (ev->ev_get < ev->ev_put) 188 kn->kn_data = ev->ev_put - ev->ev_get; 189 else 190 kn->kn_data = (EV_QSIZE - ev->ev_get) + 191 ev->ev_put; 192 193 kn->kn_data *= sizeof(struct firm_event); 194 195 return (1); 196 } 197 198 static const struct filterops ev_filtops = 199 { 1, NULL, filt_evrdetach, filt_evread }; 200 201 int 202 ev_kqfilter(struct evvar *ev, struct knote *kn) 203 { 204 struct klist *klist; 205 int s; 206 207 switch (kn->kn_filter) { 208 case EVFILT_READ: 209 klist = &ev->ev_sel.sel_klist; 210 kn->kn_fop = &ev_filtops; 211 break; 212 213 default: 214 return (1); 215 } 216 217 kn->kn_hook = ev; 218 219 s = splev(); 220 SLIST_INSERT_HEAD(klist, kn, kn_selnext); 221 splx(s); 222 223 return (0); 224 } 225