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Revision: 1.59
Committed: Sun Nov 4 18:15:16 2007 UTC (16 years, 8 months ago) by root
Content type: text/plain
Branch: MAIN
Changes since 1.58: +11 -9 lines
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# Content
1 /*
2 * libev event processing core, watcher management
3 *
4 * Copyright (c) 2007 Marc Alexander Lehmann <libev@schmorp.de>
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions are
9 * met:
10 *
11 * * Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 *
14 * * Redistributions in binary form must reproduce the above
15 * copyright notice, this list of conditions and the following
16 * disclaimer in the documentation and/or other materials provided
17 * with the distribution.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
20 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
21 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
22 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
23 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
24 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
25 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
26 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
27 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
28 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
29 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
30 */
31 #ifndef EV_STANDALONE
32 # include "config.h"
33 #endif
34
35 #include <math.h>
36 #include <stdlib.h>
37 #include <unistd.h>
38 #include <fcntl.h>
39 #include <signal.h>
40 #include <stddef.h>
41
42 #include <stdio.h>
43
44 #include <assert.h>
45 #include <errno.h>
46 #include <sys/types.h>
47 #ifndef WIN32
48 # include <sys/wait.h>
49 #endif
50 #include <sys/time.h>
51 #include <time.h>
52
53 /**/
54
55 #ifndef EV_USE_MONOTONIC
56 # define EV_USE_MONOTONIC 1
57 #endif
58
59 #ifndef EV_USE_SELECT
60 # define EV_USE_SELECT 1
61 #endif
62
63 #ifndef EV_USE_POLL
64 # define EV_USE_POLL 0 /* poll is usually slower than select, and not as well tested */
65 #endif
66
67 #ifndef EV_USE_EPOLL
68 # define EV_USE_EPOLL 0
69 #endif
70
71 #ifndef EV_USE_KQUEUE
72 # define EV_USE_KQUEUE 0
73 #endif
74
75 #ifndef EV_USE_REALTIME
76 # define EV_USE_REALTIME 1
77 #endif
78
79 /**/
80
81 #ifndef CLOCK_MONOTONIC
82 # undef EV_USE_MONOTONIC
83 # define EV_USE_MONOTONIC 0
84 #endif
85
86 #ifndef CLOCK_REALTIME
87 # undef EV_USE_REALTIME
88 # define EV_USE_REALTIME 0
89 #endif
90
91 /**/
92
93 #define MIN_TIMEJUMP 1. /* minimum timejump that gets detected (if monotonic clock available) */
94 #define MAX_BLOCKTIME 59.731 /* never wait longer than this time (to detect time jumps) */
95 #define PID_HASHSIZE 16 /* size of pid hash table, must be power of two */
96 /*#define CLEANUP_INTERVAL 300. /* how often to try to free memory and re-check fds */
97
98 #include "ev.h"
99
100 #if __GNUC__ >= 3
101 # define expect(expr,value) __builtin_expect ((expr),(value))
102 # define inline inline
103 #else
104 # define expect(expr,value) (expr)
105 # define inline static
106 #endif
107
108 #define expect_false(expr) expect ((expr) != 0, 0)
109 #define expect_true(expr) expect ((expr) != 0, 1)
110
111 #define NUMPRI (EV_MAXPRI - EV_MINPRI + 1)
112 #define ABSPRI(w) ((w)->priority - EV_MINPRI)
113
114 typedef struct ev_watcher *W;
115 typedef struct ev_watcher_list *WL;
116 typedef struct ev_watcher_time *WT;
117
118 static int have_monotonic; /* did clock_gettime (CLOCK_MONOTONIC) work? */
119
120 /*****************************************************************************/
121
122 typedef struct
123 {
124 struct ev_watcher_list *head;
125 unsigned char events;
126 unsigned char reify;
127 } ANFD;
128
129 typedef struct
130 {
131 W w;
132 int events;
133 } ANPENDING;
134
135 #if EV_MULTIPLICITY
136
137 struct ev_loop
138 {
139 # define VAR(name,decl) decl;
140 # include "ev_vars.h"
141 };
142 # undef VAR
143 # include "ev_wrap.h"
144
145 #else
146
147 # define VAR(name,decl) static decl;
148 # include "ev_vars.h"
149 # undef VAR
150
151 #endif
152
153 /*****************************************************************************/
154
155 inline ev_tstamp
156 ev_time (void)
157 {
158 #if EV_USE_REALTIME
159 struct timespec ts;
160 clock_gettime (CLOCK_REALTIME, &ts);
161 return ts.tv_sec + ts.tv_nsec * 1e-9;
162 #else
163 struct timeval tv;
164 gettimeofday (&tv, 0);
165 return tv.tv_sec + tv.tv_usec * 1e-6;
166 #endif
167 }
168
169 inline ev_tstamp
170 get_clock (void)
171 {
172 #if EV_USE_MONOTONIC
173 if (expect_true (have_monotonic))
174 {
175 struct timespec ts;
176 clock_gettime (CLOCK_MONOTONIC, &ts);
177 return ts.tv_sec + ts.tv_nsec * 1e-9;
178 }
179 #endif
180
181 return ev_time ();
182 }
183
184 ev_tstamp
185 ev_now (EV_P)
186 {
187 return rt_now;
188 }
189
190 #define array_roundsize(base,n) ((n) | 4 & ~3)
191
192 #define array_needsize(base,cur,cnt,init) \
193 if (expect_false ((cnt) > cur)) \
194 { \
195 int newcnt = cur; \
196 do \
197 { \
198 newcnt = array_roundsize (base, newcnt << 1); \
199 } \
200 while ((cnt) > newcnt); \
201 \
202 base = realloc (base, sizeof (*base) * (newcnt)); \
203 init (base + cur, newcnt - cur); \
204 cur = newcnt; \
205 }
206
207 /*****************************************************************************/
208
209 static void
210 anfds_init (ANFD *base, int count)
211 {
212 while (count--)
213 {
214 base->head = 0;
215 base->events = EV_NONE;
216 base->reify = 0;
217
218 ++base;
219 }
220 }
221
222 static void
223 event (EV_P_ W w, int events)
224 {
225 if (w->pending)
226 {
227 pendings [ABSPRI (w)][w->pending - 1].events |= events;
228 return;
229 }
230
231 w->pending = ++pendingcnt [ABSPRI (w)];
232 array_needsize (pendings [ABSPRI (w)], pendingmax [ABSPRI (w)], pendingcnt [ABSPRI (w)], );
233 pendings [ABSPRI (w)][w->pending - 1].w = w;
234 pendings [ABSPRI (w)][w->pending - 1].events = events;
235 }
236
237 static void
238 queue_events (EV_P_ W *events, int eventcnt, int type)
239 {
240 int i;
241
242 for (i = 0; i < eventcnt; ++i)
243 event (EV_A_ events [i], type);
244 }
245
246 static void
247 fd_event (EV_P_ int fd, int events)
248 {
249 ANFD *anfd = anfds + fd;
250 struct ev_io *w;
251
252 for (w = (struct ev_io *)anfd->head; w; w = (struct ev_io *)((WL)w)->next)
253 {
254 int ev = w->events & events;
255
256 if (ev)
257 event (EV_A_ (W)w, ev);
258 }
259 }
260
261 /*****************************************************************************/
262
263 static void
264 fd_reify (EV_P)
265 {
266 int i;
267
268 for (i = 0; i < fdchangecnt; ++i)
269 {
270 int fd = fdchanges [i];
271 ANFD *anfd = anfds + fd;
272 struct ev_io *w;
273
274 int events = 0;
275
276 for (w = (struct ev_io *)anfd->head; w; w = (struct ev_io *)((WL)w)->next)
277 events |= w->events;
278
279 anfd->reify = 0;
280
281 if (anfd->events != events)
282 {
283 method_modify (EV_A_ fd, anfd->events, events);
284 anfd->events = events;
285 }
286 }
287
288 fdchangecnt = 0;
289 }
290
291 static void
292 fd_change (EV_P_ int fd)
293 {
294 if (anfds [fd].reify || fdchangecnt < 0)
295 return;
296
297 anfds [fd].reify = 1;
298
299 ++fdchangecnt;
300 array_needsize (fdchanges, fdchangemax, fdchangecnt, );
301 fdchanges [fdchangecnt - 1] = fd;
302 }
303
304 static void
305 fd_kill (EV_P_ int fd)
306 {
307 struct ev_io *w;
308
309 while ((w = (struct ev_io *)anfds [fd].head))
310 {
311 ev_io_stop (EV_A_ w);
312 event (EV_A_ (W)w, EV_ERROR | EV_READ | EV_WRITE);
313 }
314 }
315
316 /* called on EBADF to verify fds */
317 static void
318 fd_ebadf (EV_P)
319 {
320 int fd;
321
322 for (fd = 0; fd < anfdmax; ++fd)
323 if (anfds [fd].events)
324 if (fcntl (fd, F_GETFD) == -1 && errno == EBADF)
325 fd_kill (EV_A_ fd);
326 }
327
328 /* called on ENOMEM in select/poll to kill some fds and retry */
329 static void
330 fd_enomem (EV_P)
331 {
332 int fd = anfdmax;
333
334 while (fd--)
335 if (anfds [fd].events)
336 {
337 close (fd);
338 fd_kill (EV_A_ fd);
339 return;
340 }
341 }
342
343 /* susually called after fork if method needs to re-arm all fds from scratch */
344 static void
345 fd_rearm_all (EV_P)
346 {
347 int fd;
348
349 /* this should be highly optimised to not do anything but set a flag */
350 for (fd = 0; fd < anfdmax; ++fd)
351 if (anfds [fd].events)
352 {
353 anfds [fd].events = 0;
354 fd_change (fd);
355 }
356 }
357
358 /*****************************************************************************/
359
360 static void
361 upheap (WT *heap, int k)
362 {
363 WT w = heap [k];
364
365 while (k && heap [k >> 1]->at > w->at)
366 {
367 heap [k] = heap [k >> 1];
368 heap [k]->active = k + 1;
369 k >>= 1;
370 }
371
372 heap [k] = w;
373 heap [k]->active = k + 1;
374
375 }
376
377 static void
378 downheap (WT *heap, int N, int k)
379 {
380 WT w = heap [k];
381
382 while (k < (N >> 1))
383 {
384 int j = k << 1;
385
386 if (j + 1 < N && heap [j]->at > heap [j + 1]->at)
387 ++j;
388
389 if (w->at <= heap [j]->at)
390 break;
391
392 heap [k] = heap [j];
393 heap [k]->active = k + 1;
394 k = j;
395 }
396
397 heap [k] = w;
398 heap [k]->active = k + 1;
399 }
400
401 /*****************************************************************************/
402
403 typedef struct
404 {
405 struct ev_watcher_list *head;
406 sig_atomic_t volatile gotsig;
407 } ANSIG;
408
409 static ANSIG *signals;
410 static int signalmax;
411
412 static int sigpipe [2];
413 static sig_atomic_t volatile gotsig;
414 static struct ev_io sigev;
415
416 static void
417 signals_init (ANSIG *base, int count)
418 {
419 while (count--)
420 {
421 base->head = 0;
422 base->gotsig = 0;
423
424 ++base;
425 }
426 }
427
428 static void
429 sighandler (int signum)
430 {
431 signals [signum - 1].gotsig = 1;
432
433 if (!gotsig)
434 {
435 int old_errno = errno;
436 gotsig = 1;
437 write (sigpipe [1], &signum, 1);
438 errno = old_errno;
439 }
440 }
441
442 static void
443 sigcb (EV_P_ struct ev_io *iow, int revents)
444 {
445 struct ev_watcher_list *w;
446 int signum;
447
448 read (sigpipe [0], &revents, 1);
449 gotsig = 0;
450
451 for (signum = signalmax; signum--; )
452 if (signals [signum].gotsig)
453 {
454 signals [signum].gotsig = 0;
455
456 for (w = signals [signum].head; w; w = w->next)
457 event (EV_A_ (W)w, EV_SIGNAL);
458 }
459 }
460
461 static void
462 siginit (EV_P)
463 {
464 #ifndef WIN32
465 fcntl (sigpipe [0], F_SETFD, FD_CLOEXEC);
466 fcntl (sigpipe [1], F_SETFD, FD_CLOEXEC);
467
468 /* rather than sort out wether we really need nb, set it */
469 fcntl (sigpipe [0], F_SETFL, O_NONBLOCK);
470 fcntl (sigpipe [1], F_SETFL, O_NONBLOCK);
471 #endif
472
473 ev_io_set (&sigev, sigpipe [0], EV_READ);
474 ev_io_start (EV_A_ &sigev);
475 ev_unref (EV_A); /* child watcher should not keep loop alive */
476 }
477
478 /*****************************************************************************/
479
480 #ifndef WIN32
481
482 static struct ev_child *childs [PID_HASHSIZE];
483 static struct ev_signal childev;
484
485 #ifndef WCONTINUED
486 # define WCONTINUED 0
487 #endif
488
489 static void
490 child_reap (EV_P_ struct ev_signal *sw, int chain, int pid, int status)
491 {
492 struct ev_child *w;
493
494 for (w = (struct ev_child *)childs [chain & (PID_HASHSIZE - 1)]; w; w = (struct ev_child *)((WL)w)->next)
495 if (w->pid == pid || !w->pid)
496 {
497 w->priority = sw->priority; /* need to do it *now* */
498 w->rpid = pid;
499 w->rstatus = status;
500 event (EV_A_ (W)w, EV_CHILD);
501 }
502 }
503
504 static void
505 childcb (EV_P_ struct ev_signal *sw, int revents)
506 {
507 int pid, status;
508
509 if (0 < (pid = waitpid (-1, &status, WNOHANG | WUNTRACED | WCONTINUED)))
510 {
511 /* make sure we are called again until all childs have been reaped */
512 event (EV_A_ (W)sw, EV_SIGNAL);
513
514 child_reap (EV_A_ sw, pid, pid, status);
515 child_reap (EV_A_ sw, 0, pid, status); /* this might trigger a watcher twice, but event catches that */
516 }
517 }
518
519 #endif
520
521 /*****************************************************************************/
522
523 #if EV_USE_KQUEUE
524 # include "ev_kqueue.c"
525 #endif
526 #if EV_USE_EPOLL
527 # include "ev_epoll.c"
528 #endif
529 #if EV_USE_POLL
530 # include "ev_poll.c"
531 #endif
532 #if EV_USE_SELECT
533 # include "ev_select.c"
534 #endif
535
536 int
537 ev_version_major (void)
538 {
539 return EV_VERSION_MAJOR;
540 }
541
542 int
543 ev_version_minor (void)
544 {
545 return EV_VERSION_MINOR;
546 }
547
548 /* return true if we are running with elevated privileges and should ignore env variables */
549 static int
550 enable_secure (void)
551 {
552 #ifdef WIN32
553 return 0;
554 #else
555 return getuid () != geteuid ()
556 || getgid () != getegid ();
557 #endif
558 }
559
560 int
561 ev_method (EV_P)
562 {
563 return method;
564 }
565
566 static void
567 loop_init (EV_P_ int methods)
568 {
569 if (!method)
570 {
571 #if EV_USE_MONOTONIC
572 {
573 struct timespec ts;
574 if (!clock_gettime (CLOCK_MONOTONIC, &ts))
575 have_monotonic = 1;
576 }
577 #endif
578
579 rt_now = ev_time ();
580 mn_now = get_clock ();
581 now_floor = mn_now;
582 rtmn_diff = rt_now - mn_now;
583
584 if (methods == EVMETHOD_AUTO)
585 if (!enable_secure () && getenv ("LIBEV_METHODS"))
586 methods = atoi (getenv ("LIBEV_METHODS"));
587 else
588 methods = EVMETHOD_ANY;
589
590 method = 0;
591 #if EV_USE_KQUEUE
592 if (!method && (methods & EVMETHOD_KQUEUE)) method = kqueue_init (EV_A_ methods);
593 #endif
594 #if EV_USE_EPOLL
595 if (!method && (methods & EVMETHOD_EPOLL )) method = epoll_init (EV_A_ methods);
596 #endif
597 #if EV_USE_POLL
598 if (!method && (methods & EVMETHOD_POLL )) method = poll_init (EV_A_ methods);
599 #endif
600 #if EV_USE_SELECT
601 if (!method && (methods & EVMETHOD_SELECT)) method = select_init (EV_A_ methods);
602 #endif
603 }
604 }
605
606 void
607 loop_destroy (EV_P)
608 {
609 #if EV_USE_KQUEUE
610 if (method == EVMETHOD_KQUEUE) kqueue_destroy (EV_A);
611 #endif
612 #if EV_USE_EPOLL
613 if (method == EVMETHOD_EPOLL ) epoll_destroy (EV_A);
614 #endif
615 #if EV_USE_POLL
616 if (method == EVMETHOD_POLL ) poll_destroy (EV_A);
617 #endif
618 #if EV_USE_SELECT
619 if (method == EVMETHOD_SELECT) select_destroy (EV_A);
620 #endif
621
622 method = 0;
623 /*TODO*/
624 }
625
626 void
627 loop_fork (EV_P)
628 {
629 /*TODO*/
630 #if EV_USE_EPOLL
631 if (method == EVMETHOD_EPOLL ) epoll_fork (EV_A);
632 #endif
633 #if EV_USE_KQUEUE
634 if (method == EVMETHOD_KQUEUE) kqueue_fork (EV_A);
635 #endif
636 }
637
638 #if EV_MULTIPLICITY
639 struct ev_loop *
640 ev_loop_new (int methods)
641 {
642 struct ev_loop *loop = (struct ev_loop *)calloc (1, sizeof (struct ev_loop));
643
644 loop_init (EV_A_ methods);
645
646 if (ev_methods (EV_A))
647 return loop;
648
649 return 0;
650 }
651
652 void
653 ev_loop_destroy (EV_P)
654 {
655 loop_destroy (EV_A);
656 free (loop);
657 }
658
659 void
660 ev_loop_fork (EV_P)
661 {
662 loop_fork (EV_A);
663 }
664
665 #endif
666
667 #if EV_MULTIPLICITY
668 struct ev_loop default_loop_struct;
669 static struct ev_loop *default_loop;
670
671 struct ev_loop *
672 #else
673 static int default_loop;
674
675 int
676 #endif
677 ev_default_loop (int methods)
678 {
679 if (sigpipe [0] == sigpipe [1])
680 if (pipe (sigpipe))
681 return 0;
682
683 if (!default_loop)
684 {
685 #if EV_MULTIPLICITY
686 struct ev_loop *loop = default_loop = &default_loop_struct;
687 #else
688 default_loop = 1;
689 #endif
690
691 loop_init (EV_A_ methods);
692
693 if (ev_method (EV_A))
694 {
695 ev_watcher_init (&sigev, sigcb);
696 ev_set_priority (&sigev, EV_MAXPRI);
697 siginit (EV_A);
698
699 #ifndef WIN32
700 ev_signal_init (&childev, childcb, SIGCHLD);
701 ev_set_priority (&childev, EV_MAXPRI);
702 ev_signal_start (EV_A_ &childev);
703 ev_unref (EV_A); /* child watcher should not keep loop alive */
704 #endif
705 }
706 else
707 default_loop = 0;
708 }
709
710 return default_loop;
711 }
712
713 void
714 ev_default_destroy (void)
715 {
716 #if EV_MULTIPLICITY
717 struct ev_loop *loop = default_loop;
718 #endif
719
720 ev_ref (EV_A); /* child watcher */
721 ev_signal_stop (EV_A_ &childev);
722
723 ev_ref (EV_A); /* signal watcher */
724 ev_io_stop (EV_A_ &sigev);
725
726 close (sigpipe [0]); sigpipe [0] = 0;
727 close (sigpipe [1]); sigpipe [1] = 0;
728
729 loop_destroy (EV_A);
730 }
731
732 void
733 ev_default_fork (EV_P)
734 {
735 loop_fork (EV_A);
736
737 ev_io_stop (EV_A_ &sigev);
738 close (sigpipe [0]);
739 close (sigpipe [1]);
740 pipe (sigpipe);
741
742 ev_ref (EV_A); /* signal watcher */
743 siginit (EV_A);
744 }
745
746 /*****************************************************************************/
747
748 static void
749 call_pending (EV_P)
750 {
751 int pri;
752
753 for (pri = NUMPRI; pri--; )
754 while (pendingcnt [pri])
755 {
756 ANPENDING *p = pendings [pri] + --pendingcnt [pri];
757
758 if (p->w)
759 {
760 p->w->pending = 0;
761 p->w->cb (EV_A_ p->w, p->events);
762 }
763 }
764 }
765
766 static void
767 timers_reify (EV_P)
768 {
769 while (timercnt && timers [0]->at <= mn_now)
770 {
771 struct ev_timer *w = timers [0];
772
773 /* first reschedule or stop timer */
774 if (w->repeat)
775 {
776 assert (("negative ev_timer repeat value found while processing timers", w->repeat > 0.));
777 w->at = mn_now + w->repeat;
778 downheap ((WT *)timers, timercnt, 0);
779 }
780 else
781 ev_timer_stop (EV_A_ w); /* nonrepeating: stop timer */
782
783 event (EV_A_ (W)w, EV_TIMEOUT);
784 }
785 }
786
787 static void
788 periodics_reify (EV_P)
789 {
790 while (periodiccnt && periodics [0]->at <= rt_now)
791 {
792 struct ev_periodic *w = periodics [0];
793
794 /* first reschedule or stop timer */
795 if (w->interval)
796 {
797 w->at += floor ((rt_now - w->at) / w->interval + 1.) * w->interval;
798 assert (("ev_periodic timeout in the past detected while processing timers, negative interval?", w->at > rt_now));
799 downheap ((WT *)periodics, periodiccnt, 0);
800 }
801 else
802 ev_periodic_stop (EV_A_ w); /* nonrepeating: stop timer */
803
804 event (EV_A_ (W)w, EV_PERIODIC);
805 }
806 }
807
808 static void
809 periodics_reschedule (EV_P)
810 {
811 int i;
812
813 /* adjust periodics after time jump */
814 for (i = 0; i < periodiccnt; ++i)
815 {
816 struct ev_periodic *w = periodics [i];
817
818 if (w->interval)
819 {
820 ev_tstamp diff = ceil ((rt_now - w->at) / w->interval) * w->interval;
821
822 if (fabs (diff) >= 1e-4)
823 {
824 ev_periodic_stop (EV_A_ w);
825 ev_periodic_start (EV_A_ w);
826
827 i = 0; /* restart loop, inefficient, but time jumps should be rare */
828 }
829 }
830 }
831 }
832
833 inline int
834 time_update_monotonic (EV_P)
835 {
836 mn_now = get_clock ();
837
838 if (expect_true (mn_now - now_floor < MIN_TIMEJUMP * .5))
839 {
840 rt_now = rtmn_diff + mn_now;
841 return 0;
842 }
843 else
844 {
845 now_floor = mn_now;
846 rt_now = ev_time ();
847 return 1;
848 }
849 }
850
851 static void
852 time_update (EV_P)
853 {
854 int i;
855
856 #if EV_USE_MONOTONIC
857 if (expect_true (have_monotonic))
858 {
859 if (time_update_monotonic (EV_A))
860 {
861 ev_tstamp odiff = rtmn_diff;
862
863 for (i = 4; --i; ) /* loop a few times, before making important decisions */
864 {
865 rtmn_diff = rt_now - mn_now;
866
867 if (fabs (odiff - rtmn_diff) < MIN_TIMEJUMP)
868 return; /* all is well */
869
870 rt_now = ev_time ();
871 mn_now = get_clock ();
872 now_floor = mn_now;
873 }
874
875 periodics_reschedule (EV_A);
876 /* no timer adjustment, as the monotonic clock doesn't jump */
877 /* timers_reschedule (EV_A_ rtmn_diff - odiff) */
878 }
879 }
880 else
881 #endif
882 {
883 rt_now = ev_time ();
884
885 if (expect_false (mn_now > rt_now || mn_now < rt_now - MAX_BLOCKTIME - MIN_TIMEJUMP))
886 {
887 periodics_reschedule (EV_A);
888
889 /* adjust timers. this is easy, as the offset is the same for all */
890 for (i = 0; i < timercnt; ++i)
891 timers [i]->at += rt_now - mn_now;
892 }
893
894 mn_now = rt_now;
895 }
896 }
897
898 void
899 ev_ref (EV_P)
900 {
901 ++activecnt;
902 }
903
904 void
905 ev_unref (EV_P)
906 {
907 --activecnt;
908 }
909
910 static int loop_done;
911
912 void
913 ev_loop (EV_P_ int flags)
914 {
915 double block;
916 loop_done = flags & (EVLOOP_ONESHOT | EVLOOP_NONBLOCK) ? 1 : 0;
917
918 do
919 {
920 /* queue check watchers (and execute them) */
921 if (expect_false (preparecnt))
922 {
923 queue_events (EV_A_ (W *)prepares, preparecnt, EV_PREPARE);
924 call_pending (EV_A);
925 }
926
927 /* update fd-related kernel structures */
928 fd_reify (EV_A);
929
930 /* calculate blocking time */
931
932 /* we only need this for !monotonic clockor timers, but as we basically
933 always have timers, we just calculate it always */
934 #if EV_USE_MONOTONIC
935 if (expect_true (have_monotonic))
936 time_update_monotonic (EV_A);
937 else
938 #endif
939 {
940 rt_now = ev_time ();
941 mn_now = rt_now;
942 }
943
944 if (flags & EVLOOP_NONBLOCK || idlecnt)
945 block = 0.;
946 else
947 {
948 block = MAX_BLOCKTIME;
949
950 if (timercnt)
951 {
952 ev_tstamp to = timers [0]->at - mn_now + method_fudge;
953 if (block > to) block = to;
954 }
955
956 if (periodiccnt)
957 {
958 ev_tstamp to = periodics [0]->at - rt_now + method_fudge;
959 if (block > to) block = to;
960 }
961
962 if (block < 0.) block = 0.;
963 }
964
965 method_poll (EV_A_ block);
966
967 /* update rt_now, do magic */
968 time_update (EV_A);
969
970 /* queue pending timers and reschedule them */
971 timers_reify (EV_A); /* relative timers called last */
972 periodics_reify (EV_A); /* absolute timers called first */
973
974 /* queue idle watchers unless io or timers are pending */
975 if (!pendingcnt)
976 queue_events (EV_A_ (W *)idles, idlecnt, EV_IDLE);
977
978 /* queue check watchers, to be executed first */
979 if (checkcnt)
980 queue_events (EV_A_ (W *)checks, checkcnt, EV_CHECK);
981
982 call_pending (EV_A);
983 }
984 while (activecnt && !loop_done);
985
986 if (loop_done != 2)
987 loop_done = 0;
988 }
989
990 void
991 ev_unloop (EV_P_ int how)
992 {
993 loop_done = how;
994 }
995
996 /*****************************************************************************/
997
998 inline void
999 wlist_add (WL *head, WL elem)
1000 {
1001 elem->next = *head;
1002 *head = elem;
1003 }
1004
1005 inline void
1006 wlist_del (WL *head, WL elem)
1007 {
1008 while (*head)
1009 {
1010 if (*head == elem)
1011 {
1012 *head = elem->next;
1013 return;
1014 }
1015
1016 head = &(*head)->next;
1017 }
1018 }
1019
1020 inline void
1021 ev_clear_pending (EV_P_ W w)
1022 {
1023 if (w->pending)
1024 {
1025 pendings [ABSPRI (w)][w->pending - 1].w = 0;
1026 w->pending = 0;
1027 }
1028 }
1029
1030 inline void
1031 ev_start (EV_P_ W w, int active)
1032 {
1033 if (w->priority < EV_MINPRI) w->priority = EV_MINPRI;
1034 if (w->priority > EV_MAXPRI) w->priority = EV_MAXPRI;
1035
1036 w->active = active;
1037 ev_ref (EV_A);
1038 }
1039
1040 inline void
1041 ev_stop (EV_P_ W w)
1042 {
1043 ev_unref (EV_A);
1044 w->active = 0;
1045 }
1046
1047 /*****************************************************************************/
1048
1049 void
1050 ev_io_start (EV_P_ struct ev_io *w)
1051 {
1052 int fd = w->fd;
1053
1054 if (ev_is_active (w))
1055 return;
1056
1057 assert (("ev_io_start called with negative fd", fd >= 0));
1058
1059 ev_start (EV_A_ (W)w, 1);
1060 array_needsize (anfds, anfdmax, fd + 1, anfds_init);
1061 wlist_add ((WL *)&anfds[fd].head, (WL)w);
1062
1063 fd_change (EV_A_ fd);
1064 }
1065
1066 void
1067 ev_io_stop (EV_P_ struct ev_io *w)
1068 {
1069 ev_clear_pending (EV_A_ (W)w);
1070 if (!ev_is_active (w))
1071 return;
1072
1073 wlist_del ((WL *)&anfds[w->fd].head, (WL)w);
1074 ev_stop (EV_A_ (W)w);
1075
1076 fd_change (EV_A_ w->fd);
1077 }
1078
1079 void
1080 ev_timer_start (EV_P_ struct ev_timer *w)
1081 {
1082 if (ev_is_active (w))
1083 return;
1084
1085 w->at += mn_now;
1086
1087 assert (("ev_timer_start called with negative timer repeat value", w->repeat >= 0.));
1088
1089 ev_start (EV_A_ (W)w, ++timercnt);
1090 array_needsize (timers, timermax, timercnt, );
1091 timers [timercnt - 1] = w;
1092 upheap ((WT *)timers, timercnt - 1);
1093 }
1094
1095 void
1096 ev_timer_stop (EV_P_ struct ev_timer *w)
1097 {
1098 ev_clear_pending (EV_A_ (W)w);
1099 if (!ev_is_active (w))
1100 return;
1101
1102 if (w->active < timercnt--)
1103 {
1104 timers [w->active - 1] = timers [timercnt];
1105 downheap ((WT *)timers, timercnt, w->active - 1);
1106 }
1107
1108 w->at = w->repeat;
1109
1110 ev_stop (EV_A_ (W)w);
1111 }
1112
1113 void
1114 ev_timer_again (EV_P_ struct ev_timer *w)
1115 {
1116 if (ev_is_active (w))
1117 {
1118 if (w->repeat)
1119 {
1120 w->at = mn_now + w->repeat;
1121 downheap ((WT *)timers, timercnt, w->active - 1);
1122 }
1123 else
1124 ev_timer_stop (EV_A_ w);
1125 }
1126 else if (w->repeat)
1127 ev_timer_start (EV_A_ w);
1128 }
1129
1130 void
1131 ev_periodic_start (EV_P_ struct ev_periodic *w)
1132 {
1133 if (ev_is_active (w))
1134 return;
1135
1136 assert (("ev_periodic_start called with negative interval value", w->interval >= 0.));
1137
1138 /* this formula differs from the one in periodic_reify because we do not always round up */
1139 if (w->interval)
1140 w->at += ceil ((rt_now - w->at) / w->interval) * w->interval;
1141
1142 ev_start (EV_A_ (W)w, ++periodiccnt);
1143 array_needsize (periodics, periodicmax, periodiccnt, );
1144 periodics [periodiccnt - 1] = w;
1145 upheap ((WT *)periodics, periodiccnt - 1);
1146 }
1147
1148 void
1149 ev_periodic_stop (EV_P_ struct ev_periodic *w)
1150 {
1151 ev_clear_pending (EV_A_ (W)w);
1152 if (!ev_is_active (w))
1153 return;
1154
1155 if (w->active < periodiccnt--)
1156 {
1157 periodics [w->active - 1] = periodics [periodiccnt];
1158 downheap ((WT *)periodics, periodiccnt, w->active - 1);
1159 }
1160
1161 ev_stop (EV_A_ (W)w);
1162 }
1163
1164 void
1165 ev_idle_start (EV_P_ struct ev_idle *w)
1166 {
1167 if (ev_is_active (w))
1168 return;
1169
1170 ev_start (EV_A_ (W)w, ++idlecnt);
1171 array_needsize (idles, idlemax, idlecnt, );
1172 idles [idlecnt - 1] = w;
1173 }
1174
1175 void
1176 ev_idle_stop (EV_P_ struct ev_idle *w)
1177 {
1178 ev_clear_pending (EV_A_ (W)w);
1179 if (ev_is_active (w))
1180 return;
1181
1182 idles [w->active - 1] = idles [--idlecnt];
1183 ev_stop (EV_A_ (W)w);
1184 }
1185
1186 void
1187 ev_prepare_start (EV_P_ struct ev_prepare *w)
1188 {
1189 if (ev_is_active (w))
1190 return;
1191
1192 ev_start (EV_A_ (W)w, ++preparecnt);
1193 array_needsize (prepares, preparemax, preparecnt, );
1194 prepares [preparecnt - 1] = w;
1195 }
1196
1197 void
1198 ev_prepare_stop (EV_P_ struct ev_prepare *w)
1199 {
1200 ev_clear_pending (EV_A_ (W)w);
1201 if (ev_is_active (w))
1202 return;
1203
1204 prepares [w->active - 1] = prepares [--preparecnt];
1205 ev_stop (EV_A_ (W)w);
1206 }
1207
1208 void
1209 ev_check_start (EV_P_ struct ev_check *w)
1210 {
1211 if (ev_is_active (w))
1212 return;
1213
1214 ev_start (EV_A_ (W)w, ++checkcnt);
1215 array_needsize (checks, checkmax, checkcnt, );
1216 checks [checkcnt - 1] = w;
1217 }
1218
1219 void
1220 ev_check_stop (EV_P_ struct ev_check *w)
1221 {
1222 ev_clear_pending (EV_A_ (W)w);
1223 if (ev_is_active (w))
1224 return;
1225
1226 checks [w->active - 1] = checks [--checkcnt];
1227 ev_stop (EV_A_ (W)w);
1228 }
1229
1230 #ifndef SA_RESTART
1231 # define SA_RESTART 0
1232 #endif
1233
1234 void
1235 ev_signal_start (EV_P_ struct ev_signal *w)
1236 {
1237 #if EV_MULTIPLICITY
1238 assert (("signal watchers are only supported in the default loop", loop == default_loop));
1239 #endif
1240 if (ev_is_active (w))
1241 return;
1242
1243 assert (("ev_signal_start called with illegal signal number", w->signum > 0));
1244
1245 ev_start (EV_A_ (W)w, 1);
1246 array_needsize (signals, signalmax, w->signum, signals_init);
1247 wlist_add ((WL *)&signals [w->signum - 1].head, (WL)w);
1248
1249 if (!w->next)
1250 {
1251 struct sigaction sa;
1252 sa.sa_handler = sighandler;
1253 sigfillset (&sa.sa_mask);
1254 sa.sa_flags = SA_RESTART; /* if restarting works we save one iteration */
1255 sigaction (w->signum, &sa, 0);
1256 }
1257 }
1258
1259 void
1260 ev_signal_stop (EV_P_ struct ev_signal *w)
1261 {
1262 ev_clear_pending (EV_A_ (W)w);
1263 if (!ev_is_active (w))
1264 return;
1265
1266 wlist_del ((WL *)&signals [w->signum - 1].head, (WL)w);
1267 ev_stop (EV_A_ (W)w);
1268
1269 if (!signals [w->signum - 1].head)
1270 signal (w->signum, SIG_DFL);
1271 }
1272
1273 void
1274 ev_child_start (EV_P_ struct ev_child *w)
1275 {
1276 #if EV_MULTIPLICITY
1277 assert (("child watchers are only supported in the default loop", loop == default_loop));
1278 #endif
1279 if (ev_is_active (w))
1280 return;
1281
1282 ev_start (EV_A_ (W)w, 1);
1283 wlist_add ((WL *)&childs [w->pid & (PID_HASHSIZE - 1)], (WL)w);
1284 }
1285
1286 void
1287 ev_child_stop (EV_P_ struct ev_child *w)
1288 {
1289 ev_clear_pending (EV_A_ (W)w);
1290 if (ev_is_active (w))
1291 return;
1292
1293 wlist_del ((WL *)&childs [w->pid & (PID_HASHSIZE - 1)], (WL)w);
1294 ev_stop (EV_A_ (W)w);
1295 }
1296
1297 /*****************************************************************************/
1298
1299 struct ev_once
1300 {
1301 struct ev_io io;
1302 struct ev_timer to;
1303 void (*cb)(int revents, void *arg);
1304 void *arg;
1305 };
1306
1307 static void
1308 once_cb (EV_P_ struct ev_once *once, int revents)
1309 {
1310 void (*cb)(int revents, void *arg) = once->cb;
1311 void *arg = once->arg;
1312
1313 ev_io_stop (EV_A_ &once->io);
1314 ev_timer_stop (EV_A_ &once->to);
1315 free (once);
1316
1317 cb (revents, arg);
1318 }
1319
1320 static void
1321 once_cb_io (EV_P_ struct ev_io *w, int revents)
1322 {
1323 once_cb (EV_A_ (struct ev_once *)(((char *)w) - offsetof (struct ev_once, io)), revents);
1324 }
1325
1326 static void
1327 once_cb_to (EV_P_ struct ev_timer *w, int revents)
1328 {
1329 once_cb (EV_A_ (struct ev_once *)(((char *)w) - offsetof (struct ev_once, to)), revents);
1330 }
1331
1332 void
1333 ev_once (EV_P_ int fd, int events, ev_tstamp timeout, void (*cb)(int revents, void *arg), void *arg)
1334 {
1335 struct ev_once *once = malloc (sizeof (struct ev_once));
1336
1337 if (!once)
1338 cb (EV_ERROR | EV_READ | EV_WRITE | EV_TIMEOUT, arg);
1339 else
1340 {
1341 once->cb = cb;
1342 once->arg = arg;
1343
1344 ev_watcher_init (&once->io, once_cb_io);
1345 if (fd >= 0)
1346 {
1347 ev_io_set (&once->io, fd, events);
1348 ev_io_start (EV_A_ &once->io);
1349 }
1350
1351 ev_watcher_init (&once->to, once_cb_to);
1352 if (timeout >= 0.)
1353 {
1354 ev_timer_set (&once->to, timeout, 0.);
1355 ev_timer_start (EV_A_ &once->to);
1356 }
1357 }
1358 }
1359