wsevent.c revision 1.26
1/* $OpenBSD: wsevent.c,v 1.26 2022/07/02 08:50:42 visa Exp $ */ 2/* $NetBSD: wsevent.c,v 1.16 2003/08/07 16:31:29 agc Exp $ */ 3 4/* 5 * Copyright (c) 1996, 1997 Christopher G. Demetriou. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. All advertising materials mentioning features or use of this software 16 * must display the following acknowledgement: 17 * This product includes software developed by Christopher G. Demetriou 18 * for the NetBSD Project. 19 * 4. The name of the author may not be used to endorse or promote products 20 * derived from this software without specific prior written permission 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 23 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 24 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 25 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 26 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 27 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 28 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 29 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 30 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 31 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 32 */ 33 34/* 35 * Copyright (c) 1992, 1993 36 * The Regents of the University of California. All rights reserved. 37 * 38 * This software was developed by the Computer Systems Engineering group 39 * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and 40 * contributed to Berkeley. 41 * 42 * All advertising materials mentioning features or use of this software 43 * must display the following acknowledgement: 44 * This product includes software developed by the University of 45 * California, Lawrence Berkeley Laboratory. 46 * 47 * Redistribution and use in source and binary forms, with or without 48 * modification, are permitted provided that the following conditions 49 * are met: 50 * 1. Redistributions of source code must retain the above copyright 51 * notice, this list of conditions and the following disclaimer. 52 * 2. Redistributions in binary form must reproduce the above copyright 53 * notice, this list of conditions and the following disclaimer in the 54 * documentation and/or other materials provided with the distribution. 55 * 3. Neither the name of the University nor the names of its contributors 56 * may be used to endorse or promote products derived from this software 57 * without specific prior written permission. 58 * 59 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 60 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 61 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 62 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 63 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 64 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 65 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 66 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 67 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 68 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 69 * SUCH DAMAGE. 70 * 71 * @(#)event.c 8.1 (Berkeley) 6/11/93 72 */ 73 74/* 75 * Internal "wscons_event" queue interface for the keyboard and mouse drivers. 76 */ 77 78#include <sys/param.h> 79#include <sys/malloc.h> 80#include <sys/systm.h> 81#include <sys/vnode.h> 82 83#include <dev/wscons/wsconsio.h> 84#include <dev/wscons/wseventvar.h> 85 86void filt_wseventdetach(struct knote *); 87int filt_wseventread(struct knote *, long); 88 89const struct filterops wsevent_filtops = { 90 .f_flags = FILTEROP_ISFD, 91 .f_attach = NULL, 92 .f_detach = filt_wseventdetach, 93 .f_event = filt_wseventread, 94}; 95 96/* 97 * Initialize a wscons_event queue. 98 */ 99int 100wsevent_init(struct wseventvar *ev) 101{ 102 struct wscons_event *queue; 103 104 if (ev->q != NULL) 105 return (0); 106 107 queue = mallocarray(WSEVENT_QSIZE, sizeof(struct wscons_event), 108 M_DEVBUF, M_WAITOK | M_ZERO); 109 if (ev->q != NULL) { 110 free(queue, M_DEVBUF, WSEVENT_QSIZE * sizeof(struct wscons_event)); 111 return (1); 112 } 113 114 ev->q = queue; 115 ev->get = ev->put = 0; 116 117 sigio_init(&ev->sigio); 118 119 return (0); 120} 121 122/* 123 * Tear down a wscons_event queue. 124 */ 125void 126wsevent_fini(struct wseventvar *ev) 127{ 128 if (ev->q == NULL) { 129#ifdef DIAGNOSTIC 130 printf("wsevent_fini: already invoked\n"); 131#endif 132 return; 133 } 134 free(ev->q, M_DEVBUF, WSEVENT_QSIZE * sizeof(struct wscons_event)); 135 ev->q = NULL; 136 137 sigio_free(&ev->sigio); 138} 139 140/* 141 * User-level interface: read, kqueue. 142 * (User cannot write an event queue.) 143 */ 144int 145wsevent_read(struct wseventvar *ev, struct uio *uio, int flags) 146{ 147 int s, error; 148 u_int cnt; 149 size_t n; 150 151 /* 152 * Make sure we can return at least 1. 153 */ 154 if (uio->uio_resid < sizeof(struct wscons_event)) 155 return (EMSGSIZE); /* ??? */ 156 s = splwsevent(); 157 while (ev->get == ev->put) { 158 if (flags & IO_NDELAY) { 159 splx(s); 160 return (EWOULDBLOCK); 161 } 162 ev->wanted = 1; 163 error = tsleep_nsec(ev, PWSEVENT | PCATCH, 164 "wsevent_read", INFSLP); 165 if (error) { 166 splx(s); 167 return (error); 168 } 169 } 170 /* 171 * Move wscons_event from tail end of queue (there is at least one 172 * there). 173 */ 174 if (ev->put < ev->get) 175 cnt = WSEVENT_QSIZE - ev->get; /* events in [get..QSIZE) */ 176 else 177 cnt = ev->put - ev->get; /* events in [get..put) */ 178 splx(s); 179 n = howmany(uio->uio_resid, sizeof(struct wscons_event)); 180 if (cnt > n) 181 cnt = n; 182 error = uiomove((caddr_t)&ev->q[ev->get], 183 cnt * sizeof(struct wscons_event), uio); 184 n -= cnt; 185 /* 186 * If we do not wrap to 0, used up all our space, or had an error, 187 * stop. Otherwise move from front of queue to put index, if there 188 * is anything there to move. 189 */ 190 if ((ev->get = (ev->get + cnt) % WSEVENT_QSIZE) != 0 || 191 n == 0 || error || (cnt = ev->put) == 0) 192 return (error); 193 if (cnt > n) 194 cnt = n; 195 error = uiomove((caddr_t)&ev->q[0], 196 cnt * sizeof(struct wscons_event), uio); 197 ev->get = cnt; 198 return (error); 199} 200 201int 202wsevent_kqfilter(struct wseventvar *ev, struct knote *kn) 203{ 204 struct klist *klist; 205 int s; 206 207 klist = &ev->sel.si_note; 208 209 switch (kn->kn_filter) { 210 case EVFILT_READ: 211 kn->kn_fop = &wsevent_filtops; 212 break; 213 default: 214 return (EINVAL); 215 } 216 217 kn->kn_hook = ev; 218 219 s = splwsevent(); 220 klist_insert_locked(klist, kn); 221 splx(s); 222 223 return (0); 224} 225 226void 227filt_wseventdetach(struct knote *kn) 228{ 229 struct wseventvar *ev = kn->kn_hook; 230 struct klist *klist = &ev->sel.si_note; 231 int s; 232 233 s = splwsevent(); 234 klist_remove_locked(klist, kn); 235 splx(s); 236} 237 238int 239filt_wseventread(struct knote *kn, long hint) 240{ 241 struct wseventvar *ev = kn->kn_hook; 242 243 if (ev->get == ev->put) 244 return (0); 245 246 if (ev->get < ev->put) 247 kn->kn_data = ev->put - ev->get; 248 else 249 kn->kn_data = (WSEVENT_QSIZE - ev->get) + ev->put; 250 251 return (1); 252} 253