wsevent.c revision 1.8
1/* $OpenBSD: wsevent.c,v 1.8 2012/12/05 23:20:22 deraadt 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/fcntl.h> 80#include <sys/malloc.h> 81#include <sys/proc.h> 82#include <sys/systm.h> 83#include <sys/vnode.h> 84#include <sys/selinfo.h> 85#include <sys/poll.h> 86 87#include <dev/wscons/wsconsio.h> 88#include <dev/wscons/wseventvar.h> 89 90/* 91 * Initialize a wscons_event queue. 92 */ 93void 94wsevent_init(struct wseventvar *ev) 95{ 96 97 if (ev->q != NULL) { 98#ifdef DIAGNOSTIC 99 printf("wsevent_init: already initialized\n"); 100#endif 101 return; 102 } 103 ev->get = ev->put = 0; 104 ev->q = malloc((u_long)WSEVENT_QSIZE * sizeof(struct wscons_event), 105 M_DEVBUF, M_WAITOK | M_ZERO); 106} 107 108/* 109 * Tear down a wscons_event queue. 110 */ 111void 112wsevent_fini(struct wseventvar *ev) 113{ 114 if (ev->q == NULL) { 115#ifdef DIAGNOSTIC 116 printf("wsevent_fini: already invoked\n"); 117#endif 118 return; 119 } 120 free(ev->q, M_DEVBUF); 121 ev->q = NULL; 122} 123 124/* 125 * User-level interface: read, poll. 126 * (User cannot write an event queue.) 127 */ 128int 129wsevent_read(struct wseventvar *ev, struct uio *uio, int flags) 130{ 131 int s, n, cnt, error; 132 133 /* 134 * Make sure we can return at least 1. 135 */ 136 if (uio->uio_resid < sizeof(struct wscons_event)) 137 return (EMSGSIZE); /* ??? */ 138 s = splwsevent(); 139 while (ev->get == ev->put) { 140 if (flags & IO_NDELAY) { 141 splx(s); 142 return (EWOULDBLOCK); 143 } 144 ev->wanted = 1; 145 error = tsleep(ev, PWSEVENT | PCATCH, 146 "wsevent_read", 0); 147 if (error) { 148 splx(s); 149 return (error); 150 } 151 } 152 /* 153 * Move wscons_event from tail end of queue (there is at least one 154 * there). 155 */ 156 if (ev->put < ev->get) 157 cnt = WSEVENT_QSIZE - ev->get; /* events in [get..QSIZE) */ 158 else 159 cnt = ev->put - ev->get; /* events in [get..put) */ 160 splx(s); 161 n = howmany(uio->uio_resid, sizeof(struct wscons_event)); 162 if (cnt > n) 163 cnt = n; 164 error = uiomove((caddr_t)&ev->q[ev->get], 165 cnt * sizeof(struct wscons_event), uio); 166 n -= cnt; 167 /* 168 * If we do not wrap to 0, used up all our space, or had an error, 169 * stop. Otherwise move from front of queue to put index, if there 170 * is anything there to move. 171 */ 172 if ((ev->get = (ev->get + cnt) % WSEVENT_QSIZE) != 0 || 173 n == 0 || error || (cnt = ev->put) == 0) 174 return (error); 175 if (cnt > n) 176 cnt = n; 177 error = uiomove((caddr_t)&ev->q[0], 178 cnt * sizeof(struct wscons_event), uio); 179 ev->get = cnt; 180 return (error); 181} 182 183int 184wsevent_poll(struct wseventvar *ev, int events, struct proc *p) 185{ 186 int revents = 0; 187 int s = splwsevent(); 188 189 if (events & (POLLIN | POLLRDNORM)) { 190 if (ev->get != ev->put) 191 revents |= events & (POLLIN | POLLRDNORM); 192 else 193 selrecord(p, &ev->sel); 194 } 195 196 splx(s); 197 return (revents); 198} 199