wsevent.c revision 1.7
1/* $OpenBSD: wsevent.c,v 1.7 2007/09/11 13:39:34 gilles 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#include <sys/cdefs.h> 35 36/* 37 * Copyright (c) 1992, 1993 38 * The Regents of the University of California. All rights reserved. 39 * 40 * This software was developed by the Computer Systems Engineering group 41 * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and 42 * contributed to Berkeley. 43 * 44 * All advertising materials mentioning features or use of this software 45 * must display the following acknowledgement: 46 * This product includes software developed by the University of 47 * California, Lawrence Berkeley Laboratory. 48 * 49 * Redistribution and use in source and binary forms, with or without 50 * modification, are permitted provided that the following conditions 51 * are met: 52 * 1. Redistributions of source code must retain the above copyright 53 * notice, this list of conditions and the following disclaimer. 54 * 2. Redistributions in binary form must reproduce the above copyright 55 * notice, this list of conditions and the following disclaimer in the 56 * documentation and/or other materials provided with the distribution. 57 * 3. Neither the name of the University nor the names of its contributors 58 * may be used to endorse or promote products derived from this software 59 * without specific prior written permission. 60 * 61 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 62 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 63 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 64 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 65 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 66 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 67 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 68 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 69 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 70 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 71 * SUCH DAMAGE. 72 * 73 * @(#)event.c 8.1 (Berkeley) 6/11/93 74 */ 75 76/* 77 * Internal "wscons_event" queue interface for the keyboard and mouse drivers. 78 */ 79 80#include <sys/param.h> 81#include <sys/fcntl.h> 82#include <sys/malloc.h> 83#include <sys/proc.h> 84#include <sys/systm.h> 85#include <sys/vnode.h> 86#include <sys/selinfo.h> 87#include <sys/poll.h> 88 89#include <dev/wscons/wsconsio.h> 90#include <dev/wscons/wseventvar.h> 91 92/* 93 * Initialize a wscons_event queue. 94 */ 95void 96wsevent_init(struct wseventvar *ev) 97{ 98 99 if (ev->q != NULL) { 100#ifdef DIAGNOSTIC 101 printf("wsevent_init: already initialized\n"); 102#endif 103 return; 104 } 105 ev->get = ev->put = 0; 106 ev->q = malloc((u_long)WSEVENT_QSIZE * sizeof(struct wscons_event), 107 M_DEVBUF, M_WAITOK | M_ZERO); 108} 109 110/* 111 * Tear down a wscons_event queue. 112 */ 113void 114wsevent_fini(struct wseventvar *ev) 115{ 116 if (ev->q == NULL) { 117#ifdef DIAGNOSTIC 118 printf("wsevent_fini: already invoked\n"); 119#endif 120 return; 121 } 122 free(ev->q, M_DEVBUF); 123 ev->q = NULL; 124} 125 126/* 127 * User-level interface: read, poll. 128 * (User cannot write an event queue.) 129 */ 130int 131wsevent_read(struct wseventvar *ev, struct uio *uio, int flags) 132{ 133 int s, n, cnt, error; 134 135 /* 136 * Make sure we can return at least 1. 137 */ 138 if (uio->uio_resid < sizeof(struct wscons_event)) 139 return (EMSGSIZE); /* ??? */ 140 s = splwsevent(); 141 while (ev->get == ev->put) { 142 if (flags & IO_NDELAY) { 143 splx(s); 144 return (EWOULDBLOCK); 145 } 146 ev->wanted = 1; 147 error = tsleep(ev, PWSEVENT | PCATCH, 148 "wsevent_read", 0); 149 if (error) { 150 splx(s); 151 return (error); 152 } 153 } 154 /* 155 * Move wscons_event from tail end of queue (there is at least one 156 * there). 157 */ 158 if (ev->put < ev->get) 159 cnt = WSEVENT_QSIZE - ev->get; /* events in [get..QSIZE) */ 160 else 161 cnt = ev->put - ev->get; /* events in [get..put) */ 162 splx(s); 163 n = howmany(uio->uio_resid, sizeof(struct wscons_event)); 164 if (cnt > n) 165 cnt = n; 166 error = uiomove((caddr_t)&ev->q[ev->get], 167 cnt * sizeof(struct wscons_event), uio); 168 n -= cnt; 169 /* 170 * If we do not wrap to 0, used up all our space, or had an error, 171 * stop. Otherwise move from front of queue to put index, if there 172 * is anything there to move. 173 */ 174 if ((ev->get = (ev->get + cnt) % WSEVENT_QSIZE) != 0 || 175 n == 0 || error || (cnt = ev->put) == 0) 176 return (error); 177 if (cnt > n) 178 cnt = n; 179 error = uiomove((caddr_t)&ev->q[0], 180 cnt * sizeof(struct wscons_event), uio); 181 ev->get = cnt; 182 return (error); 183} 184 185int 186wsevent_poll(struct wseventvar *ev, int events, struct proc *p) 187{ 188 int revents = 0; 189 int s = splwsevent(); 190 191 if (events & (POLLIN | POLLRDNORM)) { 192 if (ev->get != ev->put) 193 revents |= events & (POLLIN | POLLRDNORM); 194 else 195 selrecord(p, &ev->sel); 196 } 197 198 splx(s); 199 return (revents); 200} 201