event.c revision 1.7
1 /* $NetBSD: event.c,v 1.7 2001/06/07 17:52:52 mrg 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. All advertising materials mentioning features or use of this software 25 * must display the following acknowledgement: 26 * This product includes software developed by the University of 27 * California, Berkeley and its contributors. 28 * 4. Neither the name of the University nor the names of its contributors 29 * may be used to endorse or promote products derived from this software 30 * without specific prior written permission. 31 * 32 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 33 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 34 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 35 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 36 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 37 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 38 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 39 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 40 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 41 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 42 * SUCH DAMAGE. 43 * 44 * @(#)event.c 8.1 (Berkeley) 6/11/93 45 */ 46 47 /* 48 * Internal `Firm_event' interface for the keyboard and mouse drivers. 49 */ 50 51 #include <sys/param.h> 52 #include <sys/fcntl.h> 53 #include <sys/malloc.h> 54 #include <sys/proc.h> 55 #include <sys/systm.h> 56 #include <sys/vnode.h> 57 #include <sys/select.h> 58 #include <sys/poll.h> 59 60 #include <machine/vuid_event.h> 61 #include <dev/sun/event_var.h> 62 63 int (*ev_out32_hook) __P((struct firm_event *, int, struct uio *)); 64 65 /* 66 * Initialize a firm_event queue. 67 */ 68 void 69 ev_init(ev) 70 struct evvar *ev; 71 { 72 73 ev->ev_get = ev->ev_put = 0; 74 ev->ev_q = malloc((u_long)EV_QSIZE * sizeof(struct firm_event), 75 M_DEVBUF, M_WAITOK); 76 bzero((caddr_t)ev->ev_q, EV_QSIZE * sizeof(struct firm_event)); 77 } 78 79 /* 80 * Tear down a firm_event queue. 81 */ 82 void 83 ev_fini(ev) 84 struct evvar *ev; 85 { 86 87 free(ev->ev_q, M_DEVBUF); 88 } 89 90 /* 91 * User-level interface: read, select. 92 * (User cannot write an event queue.) 93 */ 94 int 95 ev_read(ev, uio, flags) 96 struct evvar *ev; 97 struct uio *uio; 98 int flags; 99 { 100 int s, n, cnt, error; 101 102 /* 103 * Make sure we can return at least 1. 104 */ 105 if (uio->uio_resid < sizeof(struct firm_event)) 106 return (EMSGSIZE); /* ??? */ 107 s = splev(); 108 while (ev->ev_get == ev->ev_put) { 109 if (flags & IO_NDELAY) { 110 splx(s); 111 return (EWOULDBLOCK); 112 } 113 ev->ev_wanted = 1; 114 error = tsleep((caddr_t)ev, PEVENT | PCATCH, "firm_event", 0); 115 if (error) { 116 splx(s); 117 return (error); 118 } 119 } 120 /* 121 * Move firm_events from tail end of queue (there is at least one 122 * there). 123 */ 124 if (ev->ev_put < ev->ev_get) 125 cnt = EV_QSIZE - ev->ev_get; /* events in [get..QSIZE) */ 126 else 127 cnt = ev->ev_put - ev->ev_get; /* events in [get..put) */ 128 splx(s); 129 n = howmany(uio->uio_resid, sizeof(struct firm_event)); 130 if (cnt > n) 131 cnt = n; 132 if ((curproc->p_flag & P_32) && ev_out32_hook != NULL) 133 error = (*ev_out32_hook)(&ev->ev_q[ev->ev_get], cnt, uio); 134 else 135 error = uiomove((caddr_t)&ev->ev_q[ev->ev_get], 136 cnt * sizeof(struct firm_event), uio); 137 n -= cnt; 138 /* 139 * If we do not wrap to 0, used up all our space, or had an error, 140 * stop. Otherwise move from front of queue to put index, if there 141 * is anything there to move. 142 */ 143 if ((ev->ev_get = (ev->ev_get + cnt) % EV_QSIZE) != 0 || 144 n == 0 || error || (cnt = ev->ev_put) == 0) 145 return (error); 146 if (cnt > n) 147 cnt = n; 148 if ((curproc->p_flag & P_32) && ev_out32_hook != NULL) 149 error = (*ev_out32_hook)(&ev->ev_q[0], cnt, uio); 150 else 151 error = uiomove((caddr_t)&ev->ev_q[0], 152 cnt * sizeof(struct firm_event), uio); 153 ev->ev_get = cnt; 154 return (error); 155 } 156 157 int 158 ev_poll(ev, events, p) 159 struct evvar *ev; 160 int events; 161 struct proc *p; 162 { 163 int s = splev(), revents = 0; 164 165 if (events & (POLLIN | POLLRDNORM)) { 166 if (ev->ev_get == ev->ev_put) 167 selrecord(p, &ev->ev_sel); 168 else 169 revents |= events & (POLLIN | POLLRDNORM); 170 } 171 revents |= events & (POLLOUT | POLLWRNORM); 172 173 splx(s); 174 return (revents); 175 } 176
Indexes created Wed Sep 24 05:09:52 GMT 2025