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Comparing libev/ev.c (file contents):
Revision 1.2 by root, Tue Oct 30 21:42:12 2007 UTC vs.
Revision 1.7 by root, Wed Oct 31 00:24:16 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);
38 44
39ev_tstamp 45ev_tstamp
40ev_time (void) 46ev_time (void)
41{ 47{
… …
129 if (ev) 135 if (ev)
130 event ((struct ev_watcher *)w, ev); 136 event ((struct ev_watcher *)w, ev);
131 } 137 }
132} 138}
133 139
134static struct ev_timer **timers; 140static struct ev_timer **atimers;
135static int timermax, timercnt; 141static int atimermax, atimercnt;
136 142
143static struct ev_timer **rtimers;
144static int rtimermax, rtimercnt;
145
137static void 146static void
138upheap (int k) 147upheap (struct ev_timer **timers, int k)
139{ 148{
140 struct ev_timer *w = timers [k]; 149 struct ev_timer *w = timers [k];
141 150
142 while (k && timers [k >> 1]->at > w->at) 151 while (k && timers [k >> 1]->at > w->at)
143 { 152 {
… …
150 timers [k]->active = k + 1; 159 timers [k]->active = k + 1;
151 160
152} 161}
153 162
154static void 163static void
155downheap (int k) 164downheap (struct ev_timer **timers, int N, int k)
156{ 165{
157 struct ev_timer *w = timers [k]; 166 struct ev_timer *w = timers [k];
158 167
159 while (k < (timercnt >> 1)) 168 while (k < (N >> 1))
160 { 169 {
161 int j = k << 1; 170 int j = k << 1;
162 171
163 if (j + 1 < timercnt && timers [j]->at > timers [j + 1]->at) 172 if (j + 1 < N && timers [j]->at > timers [j + 1]->at)
164 ++j; 173 ++j;
165 174
166 if (w->at <= timers [j]->at) 175 if (w->at <= timers [j]->at)
167 break; 176 break;
168 177
… …
173 182
174 timers [k] = w; 183 timers [k] = w;
175 timers [k]->active = k + 1; 184 timers [k]->active = k + 1;
176} 185}
177 186
178static struct ev_signal **signals; 187typedef struct
188{
189 struct ev_signal *head;
190 sig_atomic_t gotsig;
191} ANSIG;
192
193static ANSIG *signals;
179static int signalmax, signalcnt; 194static int signalmax;
180 195
196static int sigpipe [2];
197static sig_atomic_t gotsig;
198static struct ev_io sigev;
199
181static void 200static void
182signals_init (struct ev_signal **base, int count) 201signals_init (ANSIG *base, int count)
183{ 202{
184 while (count--) 203 while (count--)
185 *base++ = 0; 204 {
205 base->head = 0;
206 base->gotsig = 0;
207 ++base;
208 }
209}
210
211static void
212sighandler (int signum)
213{
214 signals [signum - 1].gotsig = 1;
215
216 if (!gotsig)
217 {
218 gotsig = 1;
219 write (sigpipe [1], &gotsig, 1);
220 }
221}
222
223static void
224sigcb (struct ev_io *iow, int revents)
225{
226 struct ev_signal *w;
227 int sig;
228
229 gotsig = 0;
230 read (sigpipe [0], &revents, 1);
231
232 for (sig = signalmax; sig--; )
233 if (signals [sig].gotsig)
234 {
235 signals [sig].gotsig = 0;
236
237 for (w = signals [sig].head; w; w = w->next)
238 event ((struct ev_watcher *)w, EV_SIGNAL);
239 }
240}
241
242static void
243siginit (void)
244{
245 fcntl (sigpipe [0], F_SETFD, FD_CLOEXEC);
246 fcntl (sigpipe [1], F_SETFD, FD_CLOEXEC);
247
248 /* rather than sort out wether we really need nb, set it */
249 fcntl (sigpipe [0], F_SETFL, O_NONBLOCK);
250 fcntl (sigpipe [1], F_SETFL, O_NONBLOCK);
251
252 evio_set (&sigev, sigpipe [0], EV_READ);
253 evio_start (&sigev);
186} 254}
187 255
188#if HAVE_EPOLL 256#if HAVE_EPOLL
189# include "ev_epoll.c" 257# include "ev_epoll.c"
190#endif 258#endif
… …
201 have_monotonic = 1; 269 have_monotonic = 1;
202 } 270 }
203#endif 271#endif
204 272
205 ev_now = ev_time (); 273 ev_now = ev_time ();
274 now = get_clock ();
275 diff = ev_now - now;
206 276
277 if (pipe (sigpipe))
278 return 0;
279
280 ev_method = EVMETHOD_NONE;
207#if HAVE_EPOLL 281#if HAVE_EPOLL
208 if (epoll_init (flags)) 282 if (ev_method == EVMETHOD_NONE) epoll_init (flags);
209 return ev_method;
210#endif 283#endif
211#if HAVE_SELECT 284#if HAVE_SELECT
212 if (select_init (flags)) 285 if (ev_method == EVMETHOD_NONE) select_init (flags);
213 return ev_method;
214#endif 286#endif
215 287
216 ev_method = EVMETHOD_NONE; 288 if (ev_method)
289 {
290 evw_init (&sigev, sigcb, 0);
291 siginit ();
292 }
293
217 return ev_method; 294 return ev_method;
218} 295}
219 296
220void ev_prefork (void) 297void ev_prefork (void)
221{ 298{
… …
226} 303}
227 304
228void ev_postfork_child (void) 305void ev_postfork_child (void)
229{ 306{
230#if HAVE_EPOLL 307#if HAVE_EPOLL
308 if (ev_method == EVMETHOD_EPOLL)
231 epoll_postfork_child (); 309 epoll_postfork_child ();
232#endif 310#endif
311
312 evio_stop (&sigev);
313 close (sigpipe [0]);
314 close (sigpipe [1]);
315 pipe (sigpipe);
316 siginit ();
317}
318
319static void
320fd_reify (void)
321{
322 int i;
323
324 for (i = 0; i < fdchangecnt; ++i)
325 {
326 int fd = fdchanges [i];
327 ANFD *anfd = anfds + fd;
328 struct ev_io *w;
329
330 int wev = 0;
331
332 for (w = anfd->head; w; w = w->next)
333 wev |= w->events;
334
335 if (anfd->wev != wev)
336 {
337 method_modify (fd, anfd->wev, wev);
338 anfd->wev = wev;
339 }
340 }
341
342 fdchangecnt = 0;
233} 343}
234 344
235static void 345static void
236call_pending () 346call_pending ()
237{ 347{
… …
250 360
251 pendingcnt = 0; 361 pendingcnt = 0;
252} 362}
253 363
254static void 364static void
255timer_reify (void) 365timers_reify (struct ev_timer **timers, int timercnt, ev_tstamp now)
256{ 366{
257 while (timercnt && timers [0]->at <= ev_now) 367 while (timercnt && timers [0]->at <= now)
258 { 368 {
259 struct ev_timer *w = timers [0]; 369 struct ev_timer *w = timers [0];
260 370
261 fprintf (stderr, "0 %f, %d c%d\n", w->at, w->active, timercnt);//D
262 /* first reschedule timer */ 371 /* first reschedule or stop timer */
263 if (w->repeat) 372 if (w->repeat)
264 { 373 {
265 fprintf (stderr, "a %f now %f repeat %f, %f\n", w->at, ev_now, w->repeat, w->repeat *1e30);//D
266 if (w->is_abs) 374 if (w->is_abs)
267 w->at += ceil ((ev_now - w->at) / w->repeat + 1.) * w->repeat; 375 w->at += floor ((now - w->at) / w->repeat + 1.) * w->repeat;
268 else 376 else
269 w->at = ev_now + w->repeat; 377 w->at = now + w->repeat;
270 378
271 fprintf (stderr, "b %f\n", w->at);//D 379 assert (w->at > now);
272 380
273 downheap (0); 381 downheap (timers, timercnt, 0);
274 } 382 }
275 else 383 else
276 { 384 {
277 fprintf (stderr, "c %f, %d c%d\n", w->at, w->active, timercnt);//D
278 evtimer_stop (w); /* nonrepeating: stop timer */ 385 evtimer_stop (w); /* nonrepeating: stop timer */
386 --timercnt; /* maybe pass by reference instead? */
279 } 387 }
280 388
281 event ((struct ev_watcher *)w, EV_TIMEOUT); 389 event ((struct ev_watcher *)w, EV_TIMEOUT);
282 } 390 }
283} 391}
284 392
393static void
394time_update ()
395{
396 int i;
397 ev_now = ev_time ();
398
399 if (have_monotonic)
400 {
401 ev_tstamp odiff = diff;
402
403 /* detecting time jumps is much more difficult */
404 for (i = 2; --i; ) /* loop a few times, before making important decisions */
405 {
406 now = get_clock ();
407 diff = ev_now - now;
408
409 if (fabs (odiff - diff) < MIN_TIMEJUMP)
410 return; /* all is well */
411
412 ev_now = ev_time ();
413 }
414
415 /* time jump detected, reschedule atimers */
416 for (i = 0; i < atimercnt; ++i)
417 {
418 struct ev_timer *w = atimers [i];
419 w->at += ceil ((ev_now - w->at) / w->repeat + 1.) * w->repeat;
420 }
421 }
422 else
423 {
424 if (now > ev_now || now < ev_now - MAX_BLOCKTIME - MIN_TIMEJUMP)
425 /* time jump detected, adjust rtimers */
426 for (i = 0; i < rtimercnt; ++i)
427 rtimers [i]->at += ev_now - now;
428
429 now = ev_now;
430 }
431}
432
285int ev_loop_done; 433int ev_loop_done;
286 434
287int ev_loop (int flags) 435void ev_loop (int flags)
288{ 436{
289 double block; 437 double block;
290 ev_loop_done = flags & EVLOOP_ONESHOT; 438 ev_loop_done = flags & EVLOOP_ONESHOT;
291 439
292 do 440 do
293 { 441 {
294 /* update fd-related kernel structures */ 442 /* update fd-related kernel structures */
295 method_reify (); fdchangecnt = 0; 443 fd_reify ();
296 444
297 /* calculate blocking time */ 445 /* calculate blocking time */
298 ev_now = ev_time ();
299
300 if (flags & EVLOOP_NONBLOCK) 446 if (flags & EVLOOP_NONBLOCK)
301 block = 0.; 447 block = 0.;
302 else if (!timercnt)
303 block = MAX_BLOCKTIME;
304 else 448 else
305 { 449 {
450 block = MAX_BLOCKTIME;
451
452 if (rtimercnt)
453 {
306 block = timers [0]->at - ev_now + method_fudge; 454 ev_tstamp to = rtimers [0]->at - get_clock () + method_fudge;
455 if (block > to) block = to;
456 }
457
458 if (atimercnt)
459 {
460 ev_tstamp to = atimers [0]->at - ev_time () + method_fudge;
461 if (block > to) block = to;
462 }
463
307 if (block < 0.) block = 0.; 464 if (block < 0.) block = 0.;
308 else if (block > MAX_BLOCKTIME) block = MAX_BLOCKTIME;
309 } 465 }
310 466
311 fprintf (stderr, "block %f\n", block);//D
312 method_poll (block); 467 method_poll (block);
313 468
469 /* update ev_now, do magic */
470 time_update ();
471
314 /* put pending timers into pendign queue and reschedule them */ 472 /* put pending timers into pendign queue and reschedule them */
315 timer_reify (); 473 /* absolute timers first */
474 timers_reify (atimers, atimercnt, ev_now);
475 /* relative timers second */
476 timers_reify (rtimers, rtimercnt, now);
316 477
317 ev_now = ev_time ();
318 call_pending (); 478 call_pending ();
319 } 479 }
320 while (!ev_loop_done); 480 while (!ev_loop_done);
321} 481}
322 482
… …
394evtimer_start (struct ev_timer *w) 554evtimer_start (struct ev_timer *w)
395{ 555{
396 if (ev_is_active (w)) 556 if (ev_is_active (w))
397 return; 557 return;
398 558
399 fprintf (stderr, "t1 %f a %d\n", w->at, w->is_abs);//D
400 if (w->is_abs) 559 if (w->is_abs)
401 { 560 {
402 /* this formula differs from the one in timer_reify becuse we do not round up */ 561 /* this formula differs from the one in timer_reify becuse we do not round up */
403 if (w->repeat) 562 if (w->repeat)
404 w->at += ceil ((ev_now - w->at) / w->repeat) * w->repeat; 563 w->at += ceil ((ev_now - w->at) / w->repeat) * w->repeat;
564
565 ev_start ((struct ev_watcher *)w, ++atimercnt);
566 array_needsize (atimers, atimermax, atimercnt, );
567 atimers [atimercnt - 1] = w;
568 upheap (atimers, atimercnt - 1);
405 } 569 }
406 else 570 else
571 {
407 w->at += ev_now; 572 w->at += now;
408 fprintf (stderr, "t2 %f a %d\n", w->at, w->is_abs);//D
409 573
410 ev_start ((struct ev_watcher *)w, ++timercnt); 574 ev_start ((struct ev_watcher *)w, ++rtimercnt);
411 array_needsize (timers, timermax, timercnt, ); 575 array_needsize (rtimers, rtimermax, rtimercnt, );
412 timers [timercnt - 1] = w; 576 rtimers [rtimercnt - 1] = w;
413 upheap (timercnt - 1); 577 upheap (rtimers, rtimercnt - 1);
578 }
579
414} 580}
415 581
416void 582void
417evtimer_stop (struct ev_timer *w) 583evtimer_stop (struct ev_timer *w)
418{ 584{
419 fprintf (stderr, "-topping %d, %d\n", w->active, timercnt);//D
420 if (!ev_is_active (w)) 585 if (!ev_is_active (w))
421 return; 586 return;
422 587
423 fprintf (stderr, "stopping %d, %d\n", w->active, timercnt);//D 588 if (w->is_abs)
589 {
424 if (w->active < timercnt) 590 if (w->active < atimercnt--)
425 { 591 {
426 timers [w->active - 1] = timers [--timercnt]; 592 atimers [w->active - 1] = atimers [atimercnt];
427 downheap (w->active - 1); 593 downheap (atimers, atimercnt, w->active - 1);
594 }
595 }
596 else
597 {
598 if (w->active < rtimercnt--)
599 {
600 rtimers [w->active - 1] = rtimers [rtimercnt];
601 downheap (rtimers, rtimercnt, w->active - 1);
602 }
428 } 603 }
429 604
430 ev_stop ((struct ev_watcher *)w); 605 ev_stop ((struct ev_watcher *)w);
431} 606}
432 607
… …
436 if (ev_is_active (w)) 611 if (ev_is_active (w))
437 return; 612 return;
438 613
439 ev_start ((struct ev_watcher *)w, 1); 614 ev_start ((struct ev_watcher *)w, 1);
440 array_needsize (signals, signalmax, w->signum, signals_init); 615 array_needsize (signals, signalmax, w->signum, signals_init);
441 wlist_add ((struct ev_watcher_list **)&signals [w->signum - 1], (struct ev_watcher_list *)w); 616 wlist_add ((struct ev_watcher_list **)&signals [w->signum - 1].head, (struct ev_watcher_list *)w);
617
618 if (!w->next)
619 {
620 struct sigaction sa;
621 sa.sa_handler = sighandler;
622 sigfillset (&sa.sa_mask);
623 sa.sa_flags = 0;
624 sigaction (w->signum, &sa, 0);
625 }
442} 626}
443 627
444void 628void
445evsignal_stop (struct ev_signal *w) 629evsignal_stop (struct ev_signal *w)
446{ 630{
447 if (!ev_is_active (w)) 631 if (!ev_is_active (w))
448 return; 632 return;
449 633
450 wlist_del ((struct ev_watcher_list **)&signals [w->signum - 1], (struct ev_watcher_list *)w); 634 wlist_del ((struct ev_watcher_list **)&signals [w->signum - 1].head, (struct ev_watcher_list *)w);
451 ev_stop ((struct ev_watcher *)w); 635 ev_stop ((struct ev_watcher *)w);
636
637 if (!signals [w->signum - 1].head)
638 signal (w->signum, SIG_DFL);
452} 639}
453 640
454/*****************************************************************************/ 641/*****************************************************************************/
455#if 1 642#if 1
456 643
… …
461} 648}
462 649
463static void 650static void
464ocb (struct ev_timer *w, int revents) 651ocb (struct ev_timer *w, int revents)
465{ 652{
466 fprintf (stderr, "timer %f,%f (%x) (%f) d%p\n", w->at, w->repeat, revents, w->at - ev_time (), w->data); 653 //fprintf (stderr, "timer %f,%f (%x) (%f) d%p\n", w->at, w->repeat, revents, w->at - ev_time (), w->data);
654 evtimer_stop (w);
655 evtimer_start (w);
656}
657
658static void
659scb (struct ev_signal *w, int revents)
660{
661 fprintf (stderr, "signal %x,%d\n", revents, w->signum);
467} 662}
468 663
469int main (void) 664int main (void)
470{ 665{
471 struct ev_io sin; 666 struct ev_io sin;
… …
474 669
475 evw_init (&sin, sin_cb, 55); 670 evw_init (&sin, sin_cb, 55);
476 evio_set (&sin, 0, EV_READ); 671 evio_set (&sin, 0, EV_READ);
477 evio_start (&sin); 672 evio_start (&sin);
478 673
479 struct ev_timer t[1000]; 674 struct ev_timer t[10000];
480 675
676#if 0
481 int i; 677 int i;
482 for (i = 0; i < 1000; ++i) 678 for (i = 0; i < 10000; ++i)
483 { 679 {
484 struct ev_timer *w = t + i; 680 struct ev_timer *w = t + i;
485 evw_init (w, ocb, i); 681 evw_init (w, ocb, i);
486 evtimer_set_rel (w, drand48 (), 0); 682 evtimer_set_abs (w, drand48 (), 0.99775533);
487 evtimer_start (w); 683 evtimer_start (w);
488 if (drand48 () < 0.5) 684 if (drand48 () < 0.5)
489 evtimer_stop (w); 685 evtimer_stop (w);
490 } 686 }
687#endif
688
689 struct ev_timer t1;
690 evw_init (&t1, ocb, 0);
691 evtimer_set_abs (&t1, 5, 10);
692 evtimer_start (&t1);
693
694 struct ev_signal sig;
695 evw_init (&sig, scb, 65535);
696 evsignal_set (&sig, SIGQUIT);
697 evsignal_start (&sig);
491 698
492 ev_loop (0); 699 ev_loop (0);
493 700
494 return 0; 701 return 0;
495} 702}

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