1 /* $NetBSD: event.c,v 1.17 2021/09/26 16:36:18 thorpej 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 * from: Header: event.c,v 1.5 92/11/26 01:10:44 torek Exp (LBL) 43 */ 44 45 /* 46 * Internal `Firm_event' interface for the keyboard and mouse drivers. 47 */ 48 49 #include <sys/cdefs.h> 50 __KERNEL_RCSID(0, "$NetBSD: event.c,v 1.17 2021/09/26 16:36:18 thorpej Exp $"); 51 52 #include <sys/param.h> 53 #include <sys/fcntl.h> 54 #include <sys/kmem.h> 55 #include <sys/proc.h> 56 #include <sys/systm.h> 57 #include <sys/vnode.h> 58 #include <sys/select.h> 59 #include <sys/poll.h> 60 61 #include <atari/dev/vuid_event.h> 62 #include <atari/dev/event_var.h> 63 64 #define EV_Q_ALLOCSIZE (EV_QSIZE * sizeof(struct firm_event)) 65 66 /* 67 * Initialize a firm_event queue. 68 */ 69 void 70 ev_init(register struct evvar *ev) 71 { 72 73 ev->ev_get = ev->ev_put = 0; 74 ev->ev_q = kmem_zalloc(EV_Q_ALLOCSIZE, KM_SLEEP); 75 selinit(&ev->ev_sel); 76 } 77 78 /* 79 * Tear down a firm_event queue. 80 */ 81 void 82 ev_fini(register struct evvar *ev) 83 { 84 85 seldestroy(&ev->ev_sel); 86 kmem_free(ev->ev_q, EV_Q_ALLOCSIZE); 87 } 88 89 /* 90 * User-level interface: read, select. 91 * (User cannot write an event queue.) 92 */ 93 int 94 ev_read(register struct evvar *ev, struct uio *uio, int flags) 95 { 96 int s, n, cnt, error; 97 98 /* 99 * Make sure we can return at least 1. 100 */ 101 if (uio->uio_resid < sizeof(struct firm_event)) 102 return (EMSGSIZE); /* ??? */ 103 s = splev(); 104 while (ev->ev_get == ev->ev_put) { 105 if (flags & IO_NDELAY) { 106 splx(s); 107 return (EWOULDBLOCK); 108 } 109 ev->ev_wanted = 1; 110 error = tsleep((void *)ev, PEVENT | PCATCH, "firm_event", 0); 111 if (error) { 112 splx(s); 113 return (error); 114 } 115 } 116 /* 117 * Move firm_events from tail end of queue (there is at least one 118 * there). 119 */ 120 if (ev->ev_put < ev->ev_get) 121 cnt = EV_QSIZE - ev->ev_get; /* events in [get..QSIZE) */ 122 else 123 cnt = ev->ev_put - ev->ev_get; /* events in [get..put) */ 124 splx(s); 125 n = howmany(uio->uio_resid, sizeof(struct firm_event)); 126 if (cnt > n) 127 cnt = n; 128 error = uiomove((void *)&ev->ev_q[ev->ev_get], 129 cnt * sizeof(struct firm_event), uio); 130 n -= cnt; 131 /* 132 * If we do not wrap to 0, used up all our space, or had an error, 133 * stop. Otherwise move from front of queue to put index, if there 134 * is anything there to move. 135 */ 136 if ((ev->ev_get = (ev->ev_get + cnt) % EV_QSIZE) != 0 || 137 n == 0 || error || (cnt = ev->ev_put) == 0) 138 return (error); 139 if (cnt > n) 140 cnt = n; 141 error = uiomove((void *)&ev->ev_q[0], 142 cnt * sizeof(struct firm_event), uio); 143 ev->ev_get = cnt; 144 return (error); 145 } 146 147 int 148 ev_poll(register struct evvar *ev, int events, struct lwp *l) 149 { 150 int revents = 0; 151 int s = splev(); 152 153 if (events & (POLLIN | POLLRDNORM)) { 154 if (ev->ev_get != ev->ev_put) 155 revents |= events & (POLLIN | POLLRDNORM); 156 else 157 selrecord(l, &ev->ev_sel); 158 } 159 splx(s); 160 return (revents); 161 } 162 163 static void 164 filt_evrdetach(struct knote *kn) 165 { 166 struct evvar *ev = kn->kn_hook; 167 int s; 168 169 s = splev(); 170 selremove_knote(&ev->ev_sel, kn); 171 splx(s); 172 } 173 174 static int 175 filt_evread(struct knote *kn, long hint) 176 { 177 struct evvar *ev = kn->kn_hook; 178 179 if (ev->ev_get == ev->ev_put) 180 return (0); 181 182 if (ev->ev_get < ev->ev_put) 183 kn->kn_data = ev->ev_put - ev->ev_get; 184 else 185 kn->kn_data = (EV_QSIZE - ev->ev_get) + 186 ev->ev_put; 187 188 kn->kn_data *= sizeof(struct firm_event); 189 190 return (1); 191 } 192 193 static const struct filterops ev_filtops = { 194 .f_flags = FILTEROP_ISFD, 195 .f_attach = NULL, 196 .f_detach = filt_evrdetach, 197 .f_event = filt_evread, 198 }; 199 200 int 201 ev_kqfilter(struct evvar *ev, struct knote *kn) 202 { 203 int s; 204 205 switch (kn->kn_filter) { 206 case EVFILT_READ: 207 kn->kn_fop = &ev_filtops; 208 break; 209 210 default: 211 return (EINVAL); 212 } 213 214 kn->kn_hook = ev; 215 216 s = splev(); 217 selrecord_knote(&ev->ev_sel, kn); 218 splx(s); 219 220 return (0); 221 } 222
Indexes created Sat Sep 20 22:09:52 GMT 2025