1 /* $NetBSD: event.c,v 1.23 2009/03/14 15:36:21 dsl 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 43 /* 44 * Internal `Firm_event' interface for the keyboard and mouse drivers. 45 */ 46 47 #include <sys/cdefs.h> 48 __KERNEL_RCSID(0, "$NetBSD: event.c,v 1.23 2009/03/14 15:36:21 dsl Exp $"); 49 50 #include <sys/param.h> 51 #include <sys/fcntl.h> 52 #include <sys/malloc.h> 53 #include <sys/proc.h> 54 #include <sys/systm.h> 55 #include <sys/vnode.h> 56 #include <sys/select.h> 57 #include <sys/poll.h> 58 59 #include <dev/sun/vuid_event.h> 60 #include <dev/sun/event_var.h> 61 62 int (*ev_out32_hook)(struct firm_event *, int, struct uio *); 63 64 /* 65 * Initialize a firm_event queue. 66 */ 67 void 68 ev_init(struct evvar *ev) 69 { 70 71 ev->ev_get = ev->ev_put = 0; 72 ev->ev_q = malloc((u_long)EV_QSIZE * sizeof(struct firm_event), 73 M_DEVBUF, M_WAITOK|M_ZERO); 74 selinit(&ev->ev_sel); 75 } 76 77 /* 78 * Tear down a firm_event queue. 79 */ 80 void 81 ev_fini(struct evvar *ev) 82 { 83 84 seldestroy(&ev->ev_sel); 85 free(ev->ev_q, M_DEVBUF); 86 } 87 88 /* 89 * User-level interface: read, select. 90 * (User cannot write an event queue.) 91 */ 92 int 93 ev_read(struct evvar *ev, struct uio *uio, int flags) 94 { 95 int s, n, cnt, error; 96 97 /* 98 * Make sure we can return at least 1. 99 */ 100 if (uio->uio_resid < sizeof(struct firm_event)) 101 return (EMSGSIZE); /* ??? */ 102 s = splev(); 103 while (ev->ev_get == ev->ev_put) { 104 if (flags & IO_NDELAY) { 105 splx(s); 106 return (EWOULDBLOCK); 107 } 108 ev->ev_wanted = 1; 109 error = tsleep((void *)ev, PEVENT | PCATCH, "firm_event", 0); 110 if (error) { 111 splx(s); 112 return (error); 113 } 114 } 115 /* 116 * Move firm_events from tail end of queue (there is at least one 117 * there). 118 */ 119 if (ev->ev_put < ev->ev_get) 120 cnt = EV_QSIZE - ev->ev_get; /* events in [get..QSIZE) */ 121 else 122 cnt = ev->ev_put - ev->ev_get; /* events in [get..put) */ 123 splx(s); 124 n = howmany(uio->uio_resid, sizeof(struct firm_event)); 125 if (cnt > n) 126 cnt = n; 127 if ((curproc->p_flag & PK_32) && ev_out32_hook != NULL) 128 error = (*ev_out32_hook)(&ev->ev_q[ev->ev_get], cnt, uio); 129 else 130 error = uiomove((void *)&ev->ev_q[ev->ev_get], 131 cnt * sizeof(struct firm_event), uio); 132 n -= cnt; 133 /* 134 * If we do not wrap to 0, used up all our space, or had an error, 135 * stop. Otherwise move from front of queue to put index, if there 136 * is anything there to move. 137 */ 138 if ((ev->ev_get = (ev->ev_get + cnt) % EV_QSIZE) != 0 || 139 n == 0 || error || (cnt = ev->ev_put) == 0) 140 return (error); 141 if (cnt > n) 142 cnt = n; 143 if ((curproc->p_flag & PK_32) && ev_out32_hook != NULL) 144 error = (*ev_out32_hook)(&ev->ev_q[0], cnt, uio); 145 else 146 error = uiomove((void *)&ev->ev_q[0], 147 cnt * sizeof(struct firm_event), uio); 148 ev->ev_get = cnt; 149 return (error); 150 } 151 152 int 153 ev_poll(struct evvar *ev, int events, struct lwp *l) 154 { 155 int s = splev(), revents = 0; 156 157 if (events & (POLLIN | POLLRDNORM)) { 158 if (ev->ev_get == ev->ev_put) 159 selrecord(l, &ev->ev_sel); 160 else 161 revents |= events & (POLLIN | POLLRDNORM); 162 } 163 revents |= events & (POLLOUT | POLLWRNORM); 164 165 splx(s); 166 return (revents); 167 } 168 169 static void 170 filt_evrdetach(struct knote *kn) 171 { 172 struct evvar *ev = kn->kn_hook; 173 int s; 174 175 s = splev(); 176 SLIST_REMOVE(&ev->ev_sel.sel_klist, kn, knote, kn_selnext); 177 splx(s); 178 } 179 180 static int 181 filt_evread(struct knote *kn, long hint) 182 { 183 struct evvar *ev = kn->kn_hook; 184 185 if (ev->ev_get == ev->ev_put) 186 return (0); 187 188 if (ev->ev_get < ev->ev_put) 189 kn->kn_data = ev->ev_put - ev->ev_get; 190 else 191 kn->kn_data = (EV_QSIZE - ev->ev_get) + 192 ev->ev_put; 193 194 kn->kn_data *= sizeof(struct firm_event); 195 196 return (1); 197 } 198 199 static const struct filterops ev_filtops = 200 { 1, NULL, filt_evrdetach, filt_evread }; 201 202 int 203 ev_kqfilter(struct evvar *ev, struct knote *kn) 204 { 205 struct klist *klist; 206 int s; 207 208 switch (kn->kn_filter) { 209 case EVFILT_READ: 210 klist = &ev->ev_sel.sel_klist; 211 kn->kn_fop = &ev_filtops; 212 break; 213 214 default: 215 return (EINVAL); 216 } 217 218 kn->kn_hook = ev; 219 220 s = splev(); 221 SLIST_INSERT_HEAD(klist, kn, kn_selnext); 222 splx(s); 223 224 return (0); 225 } 226