ViewVC Help
View File | Revision Log | Show Annotations | Download File
/cvs/libev/ev.c
(Generate patch)

Comparing libev/ev.c (file contents):
Revision 1.3 by root, Tue Oct 30 21:45:00 2007 UTC vs.
Revision 1.8 by root, Wed Oct 31 00:32:33 2007 UTC

1#include <math.h> 1#include <math.h>
2#include <stdlib.h> 2#include <stdlib.h>
3#include <unistd.h>
4#include <fcntl.h>
5#include <signal.h>
3 6
4#include <stdio.h> 7#include <stdio.h>
5 8
9#include <assert.h>
6#include <errno.h> 10#include <errno.h>
7#include <sys/time.h> 11#include <sys/time.h>
8#include <time.h> 12#include <time.h>
9 13
10#ifdef CLOCK_MONOTONIC 14#ifdef CLOCK_MONOTONIC
11# define HAVE_MONOTONIC 1 15# define HAVE_MONOTONIC 1
12#endif 16#endif
13 17
18#define HAVE_REALTIME 1
14#define HAVE_EPOLL 1 19#define HAVE_EPOLL 1
15#define HAVE_REALTIME 1
16#define HAVE_SELECT 0 20#define HAVE_SELECT 1
17 21
22#define MIN_TIMEJUMP 1. /* minimum timejump that gets detected (if monotonic clock available) */
18#define MAX_BLOCKTIME 60. 23#define MAX_BLOCKTIME 60.
19 24
20#include "ev.h" 25#include "ev.h"
21 26
22struct ev_watcher { 27struct ev_watcher {
… …
25 30
26struct ev_watcher_list { 31struct ev_watcher_list {
27 EV_WATCHER_LIST (ev_watcher_list); 32 EV_WATCHER_LIST (ev_watcher_list);
28}; 33};
29 34
35static ev_tstamp now, diff; /* monotonic clock */
30ev_tstamp ev_now; 36ev_tstamp ev_now;
31int ev_method; 37int ev_method;
32 38
33static int have_monotonic; /* runtime */ 39static int have_monotonic; /* runtime */
34 40
35static ev_tstamp method_fudge; /* stupid epoll-returns-early bug */ 41static ev_tstamp method_fudge; /* stupid epoll-returns-early bug */
36static void (*method_reify)(void); 42static void (*method_modify)(int fd, int oev, int nev);
37static void (*method_poll)(ev_tstamp timeout); 43static void (*method_poll)(ev_tstamp timeout);
44
45/*****************************************************************************/
38 46
39ev_tstamp 47ev_tstamp
40ev_time (void) 48ev_time (void)
41{ 49{
42#if HAVE_REALTIME 50#if HAVE_REALTIME
… …
73 base = realloc (base, sizeof (*base) * (newcnt)); \ 81 base = realloc (base, sizeof (*base) * (newcnt)); \
74 init (base + cur, newcnt - cur); \ 82 init (base + cur, newcnt - cur); \
75 cur = newcnt; \ 83 cur = newcnt; \
76 } 84 }
77 85
86/*****************************************************************************/
87
78typedef struct 88typedef struct
79{ 89{
80 struct ev_io *head; 90 struct ev_io *head;
81 unsigned char wev, rev; /* want, received event set */ 91 unsigned char wev, rev; /* want, received event set */
82} ANFD; 92} ANFD;
… …
129 if (ev) 139 if (ev)
130 event ((struct ev_watcher *)w, ev); 140 event ((struct ev_watcher *)w, ev);
131 } 141 }
132} 142}
133 143
144/*****************************************************************************/
145
134static struct ev_timer **timers; 146static struct ev_timer **atimers;
135static int timermax, timercnt; 147static int atimermax, atimercnt;
136 148
149static struct ev_timer **rtimers;
150static int rtimermax, rtimercnt;
151
137static void 152static void
138upheap (int k) 153upheap (struct ev_timer **timers, int k)
139{ 154{
140 struct ev_timer *w = timers [k]; 155 struct ev_timer *w = timers [k];
141 156
142 while (k && timers [k >> 1]->at > w->at) 157 while (k && timers [k >> 1]->at > w->at)
143 { 158 {
… …
150 timers [k]->active = k + 1; 165 timers [k]->active = k + 1;
151 166
152} 167}
153 168
154static void 169static void
155downheap (int k) 170downheap (struct ev_timer **timers, int N, int k)
156{ 171{
157 struct ev_timer *w = timers [k]; 172 struct ev_timer *w = timers [k];
158 173
159 while (k < (timercnt >> 1)) 174 while (k < (N >> 1))
160 { 175 {
161 int j = k << 1; 176 int j = k << 1;
162 177
163 if (j + 1 < timercnt && timers [j]->at > timers [j + 1]->at) 178 if (j + 1 < N && timers [j]->at > timers [j + 1]->at)
164 ++j; 179 ++j;
165 180
166 if (w->at <= timers [j]->at) 181 if (w->at <= timers [j]->at)
167 break; 182 break;
168 183
… …
173 188
174 timers [k] = w; 189 timers [k] = w;
175 timers [k]->active = k + 1; 190 timers [k]->active = k + 1;
176} 191}
177 192
178static struct ev_signal **signals; 193/*****************************************************************************/
194
195typedef struct
196{
197 struct ev_signal *head;
198 sig_atomic_t gotsig;
199} ANSIG;
200
201static ANSIG *signals;
179static int signalmax, signalcnt; 202static int signalmax;
180 203
204static int sigpipe [2];
205static sig_atomic_t gotsig;
206static struct ev_io sigev;
207
181static void 208static void
182signals_init (struct ev_signal **base, int count) 209signals_init (ANSIG *base, int count)
183{ 210{
184 while (count--) 211 while (count--)
185 *base++ = 0; 212 {
213 base->head = 0;
214 base->gotsig = 0;
215 ++base;
216 }
186} 217}
218
219static void
220sighandler (int signum)
221{
222 signals [signum - 1].gotsig = 1;
223
224 if (!gotsig)
225 {
226 gotsig = 1;
227 write (sigpipe [1], &gotsig, 1);
228 }
229}
230
231static void
232sigcb (struct ev_io *iow, int revents)
233{
234 struct ev_signal *w;
235 int sig;
236
237 gotsig = 0;
238 read (sigpipe [0], &revents, 1);
239
240 for (sig = signalmax; sig--; )
241 if (signals [sig].gotsig)
242 {
243 signals [sig].gotsig = 0;
244
245 for (w = signals [sig].head; w; w = w->next)
246 event ((struct ev_watcher *)w, EV_SIGNAL);
247 }
248}
249
250static void
251siginit (void)
252{
253 fcntl (sigpipe [0], F_SETFD, FD_CLOEXEC);
254 fcntl (sigpipe [1], F_SETFD, FD_CLOEXEC);
255
256 /* rather than sort out wether we really need nb, set it */
257 fcntl (sigpipe [0], F_SETFL, O_NONBLOCK);
258 fcntl (sigpipe [1], F_SETFL, O_NONBLOCK);
259
260 evio_set (&sigev, sigpipe [0], EV_READ);
261 evio_start (&sigev);
262}
263
264/*****************************************************************************/
187 265
188#if HAVE_EPOLL 266#if HAVE_EPOLL
189# include "ev_epoll.c" 267# include "ev_epoll.c"
190#endif 268#endif
191#if HAVE_SELECT 269#if HAVE_SELECT
… …
201 have_monotonic = 1; 279 have_monotonic = 1;
202 } 280 }
203#endif 281#endif
204 282
205 ev_now = ev_time (); 283 ev_now = ev_time ();
284 now = get_clock ();
285 diff = ev_now - now;
206 286
287 if (pipe (sigpipe))
288 return 0;
289
290 ev_method = EVMETHOD_NONE;
207#if HAVE_EPOLL 291#if HAVE_EPOLL
208 if (epoll_init (flags)) 292 if (ev_method == EVMETHOD_NONE) epoll_init (flags);
209 return ev_method;
210#endif 293#endif
211#if HAVE_SELECT 294#if HAVE_SELECT
212 if (select_init (flags)) 295 if (ev_method == EVMETHOD_NONE) select_init (flags);
213 return ev_method;
214#endif 296#endif
215 297
216 ev_method = EVMETHOD_NONE; 298 if (ev_method)
299 {
300 evw_init (&sigev, sigcb, 0);
301 siginit ();
302 }
303
217 return ev_method; 304 return ev_method;
218} 305}
219 306
307/*****************************************************************************/
308
220void ev_prefork (void) 309void ev_prefork (void)
221{ 310{
222} 311}
223 312
224void ev_postfork_parent (void) 313void ev_postfork_parent (void)
… …
226} 315}
227 316
228void ev_postfork_child (void) 317void ev_postfork_child (void)
229{ 318{
230#if HAVE_EPOLL 319#if HAVE_EPOLL
320 if (ev_method == EVMETHOD_EPOLL)
231 epoll_postfork_child (); 321 epoll_postfork_child ();
232#endif 322#endif
323
324 evio_stop (&sigev);
325 close (sigpipe [0]);
326 close (sigpipe [1]);
327 pipe (sigpipe);
328 siginit ();
329}
330
331/*****************************************************************************/
332
333static ev_hook hooks [EVHOOK_NUM];
334
335void
336ev_hook_register (int type, ev_hook hook)
337{
338 hooks [type] = hook;
339}
340
341void
342ev_hook_unregister (int type, ev_hook hook)
343{
344 hooks [type] = 0;
345}
346
347static void
348hook_call (int type)
349{
350 if (hooks [type])
351 hooks [type] ();
352}
353
354static void
355fd_reify (void)
356{
357 int i;
358
359 for (i = 0; i < fdchangecnt; ++i)
360 {
361 int fd = fdchanges [i];
362 ANFD *anfd = anfds + fd;
363 struct ev_io *w;
364
365 int wev = 0;
366
367 for (w = anfd->head; w; w = w->next)
368 wev |= w->events;
369
370 if (anfd->wev != wev)
371 {
372 method_modify (fd, anfd->wev, wev);
373 anfd->wev = wev;
374 }
375 }
376
377 fdchangecnt = 0;
233} 378}
234 379
235static void 380static void
236call_pending () 381call_pending ()
237{ 382{
… …
250 395
251 pendingcnt = 0; 396 pendingcnt = 0;
252} 397}
253 398
254static void 399static void
255timer_reify (void) 400timers_reify (struct ev_timer **timers, int timercnt, ev_tstamp now)
256{ 401{
257 while (timercnt && timers [0]->at <= ev_now) 402 while (timercnt && timers [0]->at <= now)
258 { 403 {
259 struct ev_timer *w = timers [0]; 404 struct ev_timer *w = timers [0];
260 405
261 /* first reschedule timer */ 406 /* first reschedule or stop timer */
262 if (w->repeat) 407 if (w->repeat)
263 { 408 {
264 if (w->is_abs) 409 if (w->is_abs)
265 w->at += ceil ((ev_now - w->at) / w->repeat + 1.) * w->repeat; 410 w->at += floor ((now - w->at) / w->repeat + 1.) * w->repeat;
266 else 411 else
267 w->at = ev_now + w->repeat; 412 w->at = now + w->repeat;
268 413
269 downheap (0); 414 assert (w->at > now);
415
416 downheap (timers, timercnt, 0);
270 } 417 }
271 else 418 else
419 {
272 evtimer_stop (w); /* nonrepeating: stop timer */ 420 evtimer_stop (w); /* nonrepeating: stop timer */
421 --timercnt; /* maybe pass by reference instead? */
422 }
273 423
274 event ((struct ev_watcher *)w, EV_TIMEOUT); 424 event ((struct ev_watcher *)w, EV_TIMEOUT);
275 } 425 }
276} 426}
277 427
428static void
429time_update ()
430{
431 int i;
432 ev_now = ev_time ();
433
434 if (have_monotonic)
435 {
436 ev_tstamp odiff = diff;
437
438 /* detecting time jumps is much more difficult */
439 for (i = 2; --i; ) /* loop a few times, before making important decisions */
440 {
441 now = get_clock ();
442 diff = ev_now - now;
443
444 if (fabs (odiff - diff) < MIN_TIMEJUMP)
445 return; /* all is well */
446
447 ev_now = ev_time ();
448 }
449
450 /* time jump detected, reschedule atimers */
451 for (i = 0; i < atimercnt; ++i)
452 {
453 struct ev_timer *w = atimers [i];
454 w->at += ceil ((ev_now - w->at) / w->repeat + 1.) * w->repeat;
455 }
456 }
457 else
458 {
459 if (now > ev_now || now < ev_now - MAX_BLOCKTIME - MIN_TIMEJUMP)
460 /* time jump detected, adjust rtimers */
461 for (i = 0; i < rtimercnt; ++i)
462 rtimers [i]->at += ev_now - now;
463
464 now = ev_now;
465 }
466}
467
278int ev_loop_done; 468int ev_loop_done;
279 469
280int ev_loop (int flags) 470void ev_loop (int flags)
281{ 471{
282 double block; 472 double block;
283 ev_loop_done = flags & EVLOOP_ONESHOT; 473 ev_loop_done = flags & EVLOOP_ONESHOT;
284 474
285 do 475 do
286 { 476 {
477 hook_call (EVHOOK_PREPOLL);
478
287 /* update fd-related kernel structures */ 479 /* update fd-related kernel structures */
288 method_reify (); fdchangecnt = 0; 480 fd_reify ();
289 481
290 /* calculate blocking time */ 482 /* calculate blocking time */
291 ev_now = ev_time ();
292
293 if (flags & EVLOOP_NONBLOCK) 483 if (flags & EVLOOP_NONBLOCK)
294 block = 0.; 484 block = 0.;
295 else if (!timercnt)
296 block = MAX_BLOCKTIME;
297 else 485 else
298 { 486 {
487 block = MAX_BLOCKTIME;
488
489 if (rtimercnt)
490 {
299 block = timers [0]->at - ev_now + method_fudge; 491 ev_tstamp to = rtimers [0]->at - get_clock () + method_fudge;
492 if (block > to) block = to;
493 }
494
495 if (atimercnt)
496 {
497 ev_tstamp to = atimers [0]->at - ev_time () + method_fudge;
498 if (block > to) block = to;
499 }
500
300 if (block < 0.) block = 0.; 501 if (block < 0.) block = 0.;
301 else if (block > MAX_BLOCKTIME) block = MAX_BLOCKTIME;
302 } 502 }
303 503
304 method_poll (block); 504 method_poll (block);
305 505
506 /* update ev_now, do magic */
507 time_update ();
508
509 hook_call (EVHOOK_POSTPOLL);
510
306 /* put pending timers into pendign queue and reschedule them */ 511 /* put pending timers into pendign queue and reschedule them */
307 timer_reify (); 512 /* absolute timers first */
513 timers_reify (atimers, atimercnt, ev_now);
514 /* relative timers second */
515 timers_reify (rtimers, rtimercnt, now);
308 516
309 ev_now = ev_time ();
310 call_pending (); 517 call_pending ();
311 } 518 }
312 while (!ev_loop_done); 519 while (!ev_loop_done);
313} 520}
521
522/*****************************************************************************/
314 523
315static void 524static void
316wlist_add (struct ev_watcher_list **head, struct ev_watcher_list *elem) 525wlist_add (struct ev_watcher_list **head, struct ev_watcher_list *elem)
317{ 526{
318 elem->next = *head; 527 elem->next = *head;
… …
348 pendings [w->pending - 1].w = 0; 557 pendings [w->pending - 1].w = 0;
349 558
350 w->active = 0; 559 w->active = 0;
351 /* nop */ 560 /* nop */
352} 561}
562
563/*****************************************************************************/
353 564
354void 565void
355evio_start (struct ev_io *w) 566evio_start (struct ev_io *w)
356{ 567{
357 if (ev_is_active (w)) 568 if (ev_is_active (w))
… …
391 if (w->is_abs) 602 if (w->is_abs)
392 { 603 {
393 /* this formula differs from the one in timer_reify becuse we do not round up */ 604 /* this formula differs from the one in timer_reify becuse we do not round up */
394 if (w->repeat) 605 if (w->repeat)
395 w->at += ceil ((ev_now - w->at) / w->repeat) * w->repeat; 606 w->at += ceil ((ev_now - w->at) / w->repeat) * w->repeat;
607
608 ev_start ((struct ev_watcher *)w, ++atimercnt);
609 array_needsize (atimers, atimermax, atimercnt, );
610 atimers [atimercnt - 1] = w;
611 upheap (atimers, atimercnt - 1);
396 } 612 }
397 else 613 else
614 {
398 w->at += ev_now; 615 w->at += now;
399 616
400 ev_start ((struct ev_watcher *)w, ++timercnt); 617 ev_start ((struct ev_watcher *)w, ++rtimercnt);
401 array_needsize (timers, timermax, timercnt, ); 618 array_needsize (rtimers, rtimermax, rtimercnt, );
402 timers [timercnt - 1] = w; 619 rtimers [rtimercnt - 1] = w;
403 upheap (timercnt - 1); 620 upheap (rtimers, rtimercnt - 1);
621 }
622
404} 623}
405 624
406void 625void
407evtimer_stop (struct ev_timer *w) 626evtimer_stop (struct ev_timer *w)
408{ 627{
409 if (!ev_is_active (w)) 628 if (!ev_is_active (w))
410 return; 629 return;
411 630
631 if (w->is_abs)
632 {
412 if (w->active < timercnt--) 633 if (w->active < atimercnt--)
413 { 634 {
414 timers [w->active - 1] = timers [timercnt]; 635 atimers [w->active - 1] = atimers [atimercnt];
415 downheap (w->active - 1); 636 downheap (atimers, atimercnt, w->active - 1);
637 }
638 }
639 else
640 {
641 if (w->active < rtimercnt--)
642 {
643 rtimers [w->active - 1] = rtimers [rtimercnt];
644 downheap (rtimers, rtimercnt, w->active - 1);
645 }
416 } 646 }
417 647
418 ev_stop ((struct ev_watcher *)w); 648 ev_stop ((struct ev_watcher *)w);
419} 649}
420 650
… …
424 if (ev_is_active (w)) 654 if (ev_is_active (w))
425 return; 655 return;
426 656
427 ev_start ((struct ev_watcher *)w, 1); 657 ev_start ((struct ev_watcher *)w, 1);
428 array_needsize (signals, signalmax, w->signum, signals_init); 658 array_needsize (signals, signalmax, w->signum, signals_init);
429 wlist_add ((struct ev_watcher_list **)&signals [w->signum - 1], (struct ev_watcher_list *)w); 659 wlist_add ((struct ev_watcher_list **)&signals [w->signum - 1].head, (struct ev_watcher_list *)w);
660
661 if (!w->next)
662 {
663 struct sigaction sa;
664 sa.sa_handler = sighandler;
665 sigfillset (&sa.sa_mask);
666 sa.sa_flags = 0;
667 sigaction (w->signum, &sa, 0);
668 }
430} 669}
431 670
432void 671void
433evsignal_stop (struct ev_signal *w) 672evsignal_stop (struct ev_signal *w)
434{ 673{
435 if (!ev_is_active (w)) 674 if (!ev_is_active (w))
436 return; 675 return;
437 676
438 wlist_del ((struct ev_watcher_list **)&signals [w->signum - 1], (struct ev_watcher_list *)w); 677 wlist_del ((struct ev_watcher_list **)&signals [w->signum - 1].head, (struct ev_watcher_list *)w);
439 ev_stop ((struct ev_watcher *)w); 678 ev_stop ((struct ev_watcher *)w);
679
680 if (!signals [w->signum - 1].head)
681 signal (w->signum, SIG_DFL);
440} 682}
441 683
442/*****************************************************************************/ 684/*****************************************************************************/
443#if 1 685#if 1
444 686
… …
449} 691}
450 692
451static void 693static void
452ocb (struct ev_timer *w, int revents) 694ocb (struct ev_timer *w, int revents)
453{ 695{
454 fprintf (stderr, "timer %f,%f (%x) (%f) d%p\n", w->at, w->repeat, revents, w->at - ev_time (), w->data); 696 //fprintf (stderr, "timer %f,%f (%x) (%f) d%p\n", w->at, w->repeat, revents, w->at - ev_time (), w->data);
697 evtimer_stop (w);
698 evtimer_start (w);
699}
700
701static void
702scb (struct ev_signal *w, int revents)
703{
704 fprintf (stderr, "signal %x,%d\n", revents, w->signum);
455} 705}
456 706
457int main (void) 707int main (void)
458{ 708{
459 struct ev_io sin; 709 struct ev_io sin;
… …
462 712
463 evw_init (&sin, sin_cb, 55); 713 evw_init (&sin, sin_cb, 55);
464 evio_set (&sin, 0, EV_READ); 714 evio_set (&sin, 0, EV_READ);
465 evio_start (&sin); 715 evio_start (&sin);
466 716
467 struct ev_timer t[1000]; 717 struct ev_timer t[10000];
468 718
719#if 1
469 int i; 720 int i;
470 for (i = 0; i < 1000; ++i) 721 for (i = 0; i < 10000; ++i)
471 { 722 {
472 struct ev_timer *w = t + i; 723 struct ev_timer *w = t + i;
473 evw_init (w, ocb, i); 724 evw_init (w, ocb, i);
474 evtimer_set_rel (w, drand48 (), 0); 725 evtimer_set_abs (w, drand48 (), 0.99775533);
475 evtimer_start (w); 726 evtimer_start (w);
476 if (drand48 () < 0.5) 727 if (drand48 () < 0.5)
477 evtimer_stop (w); 728 evtimer_stop (w);
478 } 729 }
730#endif
731
732 struct ev_timer t1;
733 evw_init (&t1, ocb, 0);
734 evtimer_set_abs (&t1, 5, 10);
735 evtimer_start (&t1);
736
737 struct ev_signal sig;
738 evw_init (&sig, scb, 65535);
739 evsignal_set (&sig, SIGQUIT);
740 evsignal_start (&sig);
479 741
480 ev_loop (0); 742 ev_loop (0);
481 743
482 return 0; 744 return 0;
483} 745}

Diff Legend

– Removed lines
+ Added lines
< Changed lines
> Changed lines