1 /* 2 * event.h 3 */ 4 5 /*- 6 * Copyright (c) 2009 Maksim Yevmenkin <m_evmenkin@yahoo.com> 7 * All rights reserved. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 21 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 28 * SUCH DAMAGE. 29 */ 30 31 /* $FreeBSD$ */ 32 33 /* 34 * Hack to provide libevent (see devel/libevent port) like API. 35 * Should be removed if FreeBSD ever decides to import libevent into base. 36 */ 37 38 #include <sys/select.h> 39 #include <sys/time.h> 40 #include <sys/queue.h> 41 #include <assert.h> 42 #include <stdarg.h> 43 #include <stdio.h> 44 #include <string.h> 45 #include <syslog.h> 46 47 #include "event.h" 48 #define L2CAP_SOCKET_CHECKED 49 #include "btpand.h" 50 51 #define __event_link(ev) \ 52 do { \ 53 TAILQ_INSERT_TAIL(&pending, ev, next); \ 54 ev->flags |= EV_PENDING; \ 55 } while (0) 56 57 static void tv_add(struct timeval *, struct timeval const *); 58 static void tv_sub(struct timeval *, struct timeval const *); 59 static int tv_cmp(struct timeval const *, struct timeval const *); 60 static int __event_dispatch(void); 61 static void __event_add_current(struct event *); 62 static void __event_del_current(struct event *); 63 64 65 static TAILQ_HEAD(, event) pending; 66 static TAILQ_HEAD(, event) current; 67 68 void 69 event_init(void) 70 { 71 TAILQ_INIT(&pending); 72 } 73 74 int 75 event_dispatch(void) 76 { 77 while (__event_dispatch() == 0) 78 ; 79 80 return (-1); 81 } 82 83 static int 84 __event_dispatch(void) 85 { 86 fd_set r, w; 87 int nfd; 88 struct event *ev; 89 struct timeval now, timeout, t; 90 91 FD_ZERO(&r); 92 FD_ZERO(&w); 93 94 nfd = 0; 95 96 gettimeofday(&now, NULL); 97 98 timeout.tv_sec = 10; /* arbitrary */ 99 timeout.tv_usec = 0; 100 101 TAILQ_INIT(¤t); 102 103 /* 104 * Build fd_set's 105 */ 106 107 event_log_debug("%s: building fd set...", __func__); 108 109 while (!TAILQ_EMPTY(&pending)) { 110 ev = TAILQ_FIRST(&pending); 111 event_del(ev); 112 113 if (ev->flags & EV_HAS_TIMEOUT) { 114 if (tv_cmp(&now, &ev->expire) >= 0) 115 t.tv_sec = t.tv_usec = 0; 116 else { 117 t = ev->expire; 118 tv_sub(&t, &now); 119 } 120 121 if (tv_cmp(&t, &timeout) < 0) 122 timeout = t; 123 } 124 125 if (ev->fd >= 0) { 126 if (ev->flags & EV_READ) { 127 FD_SET(ev->fd, &r); 128 nfd = (nfd > ev->fd) ? nfd : ev->fd; 129 } 130 131 if (ev->flags & EV_WRITE) { 132 FD_SET(ev->fd, &w); 133 nfd = (nfd > ev->fd) ? nfd : ev->fd; 134 } 135 } 136 137 __event_add_current(ev); 138 } 139 140 event_log_debug("%s: waiting for events...", __func__); 141 142 nfd = select(nfd + 1, &r, &w, NULL, &timeout); 143 if (nfd < 0) 144 return (-1); 145 146 /* 147 * Process current pending 148 */ 149 150 event_log_debug("%s: processing events...", __func__); 151 152 gettimeofday(&now, NULL); 153 154 while (!TAILQ_EMPTY(¤t)) { 155 ev = TAILQ_FIRST(¤t); 156 __event_del_current(ev); 157 158 /* check if fd is ready for reading/writing */ 159 if (nfd > 0 && ev->fd >= 0) { 160 if (FD_ISSET(ev->fd, &r) || FD_ISSET(ev->fd, &w)) { 161 if (ev->flags & EV_PERSIST) { 162 if (ev->flags & EV_HAS_TIMEOUT) 163 event_add(ev, &ev->timeout); 164 else 165 event_add(ev, NULL); 166 } 167 168 nfd --; 169 170 event_log_debug("%s: calling %p(%d, %p), " \ 171 "ev=%p", __func__, ev->cb, ev->fd, 172 ev->cbarg, ev); 173 174 (ev->cb)(ev->fd, 175 (ev->flags & (EV_READ|EV_WRITE)), 176 ev->cbarg); 177 178 continue; 179 } 180 } 181 182 /* if event has no timeout - just requeue */ 183 if ((ev->flags & EV_HAS_TIMEOUT) == 0) { 184 event_add(ev, NULL); 185 continue; 186 } 187 188 /* check if event has expired */ 189 if (tv_cmp(&now, &ev->expire) >= 0) { 190 if (ev->flags & EV_PERSIST) 191 event_add(ev, &ev->timeout); 192 193 event_log_debug("%s: calling %p(%d, %p), ev=%p", 194 __func__, ev->cb, ev->fd, ev->cbarg, ev); 195 196 (ev->cb)(ev->fd, 197 (ev->flags & (EV_READ|EV_WRITE)), 198 ev->cbarg); 199 200 continue; 201 } 202 203 assert((ev->flags & (EV_PENDING|EV_CURRENT)) == 0); 204 __event_link(ev); 205 } 206 207 return (0); 208 } 209 210 void 211 __event_set(struct event *ev, int fd, short flags, 212 void (*cb)(int, short, void *), void *cbarg) 213 { 214 ev->fd = fd; 215 ev->flags = flags; 216 ev->cb = cb; 217 ev->cbarg = cbarg; 218 } 219 220 int 221 __event_add(struct event *ev, const struct timeval *timeout) 222 { 223 assert((ev->flags & (EV_PENDING|EV_CURRENT)) == 0); 224 225 if (timeout != NULL) { 226 gettimeofday(&ev->expire, NULL); 227 tv_add(&ev->expire, timeout); 228 ev->timeout = *timeout; 229 ev->flags |= EV_HAS_TIMEOUT; 230 } else 231 ev->flags &= ~EV_HAS_TIMEOUT; 232 233 __event_link(ev); 234 235 return (0); 236 } 237 238 int 239 __event_del(struct event *ev) 240 { 241 assert((ev->flags & EV_CURRENT) == 0); 242 243 if ((ev->flags & EV_PENDING) != 0) { 244 TAILQ_REMOVE(&pending, ev, next); 245 ev->flags &= ~EV_PENDING; 246 } 247 248 return (0); 249 } 250 251 static void 252 __event_add_current(struct event *ev) 253 { 254 assert((ev->flags & (EV_PENDING|EV_CURRENT)) == 0); 255 256 TAILQ_INSERT_TAIL(¤t, ev, next); 257 ev->flags |= EV_CURRENT; 258 } 259 260 static void 261 __event_del_current(struct event *ev) 262 { 263 assert((ev->flags & (EV_CURRENT|EV_PENDING)) == EV_CURRENT); 264 265 TAILQ_REMOVE(¤t, ev, next); 266 ev->flags &= ~EV_CURRENT; 267 } 268 269 static void 270 tv_add(struct timeval *a, struct timeval const *b) 271 { 272 a->tv_sec += b->tv_sec; 273 a->tv_usec += b->tv_usec; 274 275 if(a->tv_usec >= 1000000) { 276 a->tv_usec -= 1000000; 277 a->tv_sec += 1; 278 } 279 } 280 281 static void 282 tv_sub(struct timeval *a, struct timeval const *b) 283 { 284 if (a->tv_usec < b->tv_usec) { 285 a->tv_usec += 1000000; 286 a->tv_sec -= 1; 287 } 288 289 a->tv_usec -= b->tv_usec; 290 a->tv_sec -= b->tv_sec; 291 } 292 293 static int 294 tv_cmp(struct timeval const *a, struct timeval const *b) 295 { 296 if (a->tv_sec > b->tv_sec) 297 return (1); 298 299 if (a->tv_sec < b->tv_sec) 300 return (-1); 301 302 if (a->tv_usec > b->tv_usec) 303 return (1); 304 305 if (a->tv_usec < b->tv_usec) 306 return (-1); 307 308 return (0); 309 } 310 311