wsevent.c revision 1.14
1/* $OpenBSD: wsevent.c,v 1.14 2015/09/10 18:14:52 mpi 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#include <sys/selinfo.h> 83#include <sys/poll.h> 84 85#include <dev/wscons/wsconsio.h> 86#include <dev/wscons/wseventvar.h> 87 88void filt_wseventdetach(struct knote *); 89int filt_wseventread(struct knote *, long); 90 91const struct filterops wsevent_filtops = { 92 1, 93 NULL, 94 filt_wseventdetach, 95 filt_wseventread 96}; 97 98/* 99 * Initialize a wscons_event queue. 100 */ 101void 102wsevent_init(struct wseventvar *ev) 103{ 104 105 if (ev->q != NULL) { 106#ifdef DIAGNOSTIC 107 printf("wsevent_init: already initialized\n"); 108#endif 109 return; 110 } 111 ev->get = ev->put = 0; 112 ev->q = malloc(WSEVENT_QSIZE * sizeof(struct wscons_event), 113 M_DEVBUF, M_WAITOK | M_ZERO); 114} 115 116/* 117 * Tear down a wscons_event queue. 118 */ 119void 120wsevent_fini(struct wseventvar *ev) 121{ 122 if (ev->q == NULL) { 123#ifdef DIAGNOSTIC 124 printf("wsevent_fini: already invoked\n"); 125#endif 126 return; 127 } 128 free(ev->q, M_DEVBUF, 0); 129 ev->q = NULL; 130} 131 132/* 133 * User-level interface: read, poll. 134 * (User cannot write an event queue.) 135 */ 136int 137wsevent_read(struct wseventvar *ev, struct uio *uio, int flags) 138{ 139 int s, n, cnt, error; 140 141 /* 142 * Make sure we can return at least 1. 143 */ 144 if (uio->uio_resid < sizeof(struct wscons_event)) 145 return (EMSGSIZE); /* ??? */ 146 s = splwsevent(); 147 while (ev->get == ev->put) { 148 if (flags & IO_NDELAY) { 149 splx(s); 150 return (EWOULDBLOCK); 151 } 152 ev->wanted = 1; 153 error = tsleep(ev, PWSEVENT | PCATCH, 154 "wsevent_read", 0); 155 if (error) { 156 splx(s); 157 return (error); 158 } 159 } 160 /* 161 * Move wscons_event from tail end of queue (there is at least one 162 * there). 163 */ 164 if (ev->put < ev->get) 165 cnt = WSEVENT_QSIZE - ev->get; /* events in [get..QSIZE) */ 166 else 167 cnt = ev->put - ev->get; /* events in [get..put) */ 168 splx(s); 169 n = howmany(uio->uio_resid, sizeof(struct wscons_event)); 170 if (cnt > n) 171 cnt = n; 172 error = uiomovei((caddr_t)&ev->q[ev->get], 173 cnt * sizeof(struct wscons_event), uio); 174 n -= cnt; 175 /* 176 * If we do not wrap to 0, used up all our space, or had an error, 177 * stop. Otherwise move from front of queue to put index, if there 178 * is anything there to move. 179 */ 180 if ((ev->get = (ev->get + cnt) % WSEVENT_QSIZE) != 0 || 181 n == 0 || error || (cnt = ev->put) == 0) 182 return (error); 183 if (cnt > n) 184 cnt = n; 185 error = uiomovei((caddr_t)&ev->q[0], 186 cnt * sizeof(struct wscons_event), uio); 187 ev->get = cnt; 188 return (error); 189} 190 191int 192wsevent_poll(struct wseventvar *ev, int events, struct proc *p) 193{ 194 int revents = 0; 195 int s = splwsevent(); 196 197 if (events & (POLLIN | POLLRDNORM)) { 198 if (ev->get != ev->put) 199 revents |= events & (POLLIN | POLLRDNORM); 200 else 201 selrecord(p, &ev->sel); 202 } 203 204 splx(s); 205 return (revents); 206} 207 208int 209wsevent_kqfilter(struct wseventvar *ev, struct knote *kn) 210{ 211 struct klist *klist; 212 int s; 213 214 klist = &ev->sel.si_note; 215 216 switch (kn->kn_filter) { 217 case EVFILT_READ: 218 kn->kn_fop = &wsevent_filtops; 219 break; 220 default: 221 return (EINVAL); 222 } 223 224 kn->kn_hook = ev; 225 226 s = splwsevent(); 227 SLIST_INSERT_HEAD(klist, kn, kn_selnext); 228 splx(s); 229 230 return (0); 231} 232 233void 234filt_wseventdetach(struct knote *kn) 235{ 236 struct wseventvar *ev = kn->kn_hook; 237 struct klist *klist = &ev->sel.si_note; 238 int s; 239 240 s = splwsevent(); 241 SLIST_REMOVE(klist, kn, knote, kn_selnext); 242 splx(s); 243} 244 245int 246filt_wseventread(struct knote *kn, long hint) 247{ 248 struct wseventvar *ev = kn->kn_hook; 249 250 if (ev->get == ev->put) 251 return (0); 252 253 if (ev->get < ev->put) 254 kn->kn_data = ev->put - ev->get; 255 else 256 kn->kn_data = (WSEVENT_QSIZE - ev->get) + ev->put; 257 258 return (1); 259} 260