1 /* $NetBSD: event.c,v 1.10 2003/08/07 16:26:41 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 * Header: event.c,v 1.5 92/11/26 01:10:44 torek Exp (LBL) 43 */ 44 45 #include <sys/cdefs.h> 46 __KERNEL_RCSID(0, "$NetBSD: event.c,v 1.10 2003/08/07 16:26:41 agc Exp $"); 47 48 /* 49 * Internal `Firm_event' interface for the keyboard and mouse drivers. 50 */ 51 52 #include <sys/param.h> 53 #include <sys/fcntl.h> 54 #include <sys/malloc.h> 55 #include <sys/poll.h> 56 #include <sys/proc.h> 57 #include <sys/select.h> 58 #include <sys/systm.h> 59 #include <sys/vnode.h> 60 61 #include <amiga/dev/vuid_event.h> 62 #include <amiga/dev/event_var.h> 63 64 /* 65 * Initialize a firm_event queue. 66 */ 67 void 68 ev_init(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 bzero((caddr_t)ev->ev_q, EV_QSIZE * sizeof(struct firm_event)); 75 } 76 77 /* 78 * Tear down a firm_event queue. 79 */ 80 void 81 ev_fini(register struct evvar *ev) 82 { 83 84 free(ev->ev_q, M_DEVBUF); 85 } 86 87 /* 88 * User-level interface: read, poll. 89 * (User cannot write an event queue.) 90 */ 91 int 92 ev_read(register struct evvar *ev, struct uio *uio, int flags) 93 { 94 int s, n, cnt, error; 95 96 /* 97 * Make sure we can return at least 1. 98 */ 99 if (uio->uio_resid < sizeof(struct firm_event)) 100 return (EMSGSIZE); /* ??? */ 101 s = splev(); 102 while (ev->ev_get == ev->ev_put) { 103 if (flags & IO_NDELAY) { 104 splx(s); 105 return (EWOULDBLOCK); 106 } 107 ev->ev_wanted = 1; 108 error = tsleep((caddr_t)ev, PEVENT | PCATCH, "firm_event", 0); 109 if (error) { 110 splx(s); 111 return (error); 112 } 113 } 114 /* 115 * Move firm_events from tail end of queue (there is at least one 116 * there). 117 */ 118 if (ev->ev_put < ev->ev_get) 119 cnt = EV_QSIZE - ev->ev_get; /* events in [get..QSIZE) */ 120 else 121 cnt = ev->ev_put - ev->ev_get; /* events in [get..put) */ 122 splx(s); 123 n = howmany(uio->uio_resid, sizeof(struct firm_event)); 124 if (cnt > n) 125 cnt = n; 126 error = uiomove((caddr_t)&ev->ev_q[ev->ev_get], 127 cnt * sizeof(struct firm_event), uio); 128 n -= cnt; 129 /* 130 * If we do not wrap to 0, used up all our space, or had an error, 131 * stop. Otherwise move from front of queue to put index, if there 132 * is anything there to move. 133 */ 134 if ((ev->ev_get = (ev->ev_get + cnt) % EV_QSIZE) != 0 || 135 n == 0 || error || (cnt = ev->ev_put) == 0) 136 return (error); 137 if (cnt > n) 138 cnt = n; 139 error = uiomove((caddr_t)&ev->ev_q[0], 140 cnt * sizeof(struct firm_event), uio); 141 ev->ev_get = cnt; 142 return (error); 143 } 144 145 int 146 ev_poll(register struct evvar *ev, int events, struct proc *p) 147 { 148 int s = splev(); 149 int revents = 0; 150 151 if (events & (POLLIN | POLLRDNORM)) 152 /* succeed if there is something to read */ 153 if (ev->ev_get != ev->ev_put) 154 revents |= events & (POLLIN | POLLRDNORM); 155 if (revents == 0) 156 if (events & (POLLIN | POLLRDNORM)) 157 selrecord(p, &ev->ev_sel); 158 splx(s); 159 return (revents); 160 } 161 162 static void 163 filt_evrdetach(struct knote *kn) 164 { 165 struct evvar *ev = kn->kn_hook; 166 int s; 167 168 s = splev(); 169 SLIST_REMOVE(&ev->ev_sel.sel_klist, kn, knote, kn_selnext); 170 splx(s); 171 } 172 173 static int 174 filt_evread(struct knote *kn, long hint) 175 { 176 struct evvar *ev = kn->kn_hook; 177 178 if (ev->ev_get == ev->ev_put) 179 return (0); 180 181 if (ev->ev_get < ev->ev_put) 182 kn->kn_data = ev->ev_put - ev->ev_get; 183 else 184 kn->kn_data = (EV_QSIZE - ev->ev_get) + 185 ev->ev_put; 186 187 kn->kn_data *= sizeof(struct firm_event); 188 189 return (1); 190 } 191 192 static const struct filterops ev_filtops = 193 { 1, NULL, filt_evrdetach, filt_evread }; 194 195 int 196 ev_kqfilter(struct evvar *ev, struct knote *kn) 197 { 198 struct klist *klist; 199 int s; 200 201 switch (kn->kn_filter) { 202 case EVFILT_READ: 203 klist = &ev->ev_sel.sel_klist; 204 kn->kn_fop = &ev_filtops; 205 break; 206 207 default: 208 return (1); 209 } 210 211 kn->kn_hook = ev; 212 213 s = splev(); 214 SLIST_INSERT_HEAD(klist, kn, kn_selnext); 215 splx(s); 216 217 return (0); 218 } 219