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Revision: 1.61
Committed: Sun Nov 4 19:45:09 2007 UTC (16 years, 6 months ago) by root
Content type: text/plain
Branch: MAIN
Changes since 1.60: +4 -0 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
34 # if HAVE_CLOCK_GETTIME
35 # define EV_USE_MONOTONIC 1
36 # define EV_USE_REALTIME 1
37 # endif
38
39 # if HAVE_SELECT && HAVE_SYS_SELECT_H
40 # define EV_USE_SELECT 1
41 # endif
42
43 # if HAVE_POLL && HAVE_POLL_H
44 # define EV_USE_POLL 1
45 # endif
46
47 # if HAVE_EPOLL && HAVE_EPOLL_CTL && HAVE_SYS_EPOLL_H
48 # define EV_USE_EPOLL 1
49 # endif
50
51 # if HAVE_KQUEUE && HAVE_WORKING_KQUEUE && HAVE_SYS_EVENT_H && HAVE_SYS_QUEUE_H
52 # define EV_USE_KQUEUE 1
53 # endif
54
55 #endif
56
57 #include <math.h>
58 #include <stdlib.h>
59 #include <unistd.h>
60 #include <fcntl.h>
61 #include <signal.h>
62 #include <stddef.h>
63
64 #include <stdio.h>
65
66 #include <assert.h>
67 #include <errno.h>
68 #include <sys/types.h>
69 #ifndef WIN32
70 # include <sys/wait.h>
71 #endif
72 #include <sys/time.h>
73 #include <time.h>
74
75 /**/
76
77 #ifndef EV_USE_MONOTONIC
78 # define EV_USE_MONOTONIC 1
79 #endif
80
81 #ifndef EV_USE_SELECT
82 # define EV_USE_SELECT 1
83 #endif
84
85 #ifndef EV_USE_POLL
86 # define EV_USE_POLL 0 /* poll is usually slower than select, and not as well tested */
87 #endif
88
89 #ifndef EV_USE_EPOLL
90 # define EV_USE_EPOLL 0
91 #endif
92
93 #ifndef EV_USE_KQUEUE
94 # define EV_USE_KQUEUE 0
95 #endif
96
97 #ifndef EV_USE_REALTIME
98 # define EV_USE_REALTIME 1
99 #endif
100
101 /**/
102
103 #ifndef CLOCK_MONOTONIC
104 # undef EV_USE_MONOTONIC
105 # define EV_USE_MONOTONIC 0
106 #endif
107
108 #ifndef CLOCK_REALTIME
109 # undef EV_USE_REALTIME
110 # define EV_USE_REALTIME 0
111 #endif
112
113 /**/
114
115 #define MIN_TIMEJUMP 1. /* minimum timejump that gets detected (if monotonic clock available) */
116 #define MAX_BLOCKTIME 59.731 /* never wait longer than this time (to detect time jumps) */
117 #define PID_HASHSIZE 16 /* size of pid hash table, must be power of two */
118 /*#define CLEANUP_INTERVAL 300. /* how often to try to free memory and re-check fds */
119
120 #include "ev.h"
121
122 #if __GNUC__ >= 3
123 # define expect(expr,value) __builtin_expect ((expr),(value))
124 # define inline inline
125 #else
126 # define expect(expr,value) (expr)
127 # define inline static
128 #endif
129
130 #define expect_false(expr) expect ((expr) != 0, 0)
131 #define expect_true(expr) expect ((expr) != 0, 1)
132
133 #define NUMPRI (EV_MAXPRI - EV_MINPRI + 1)
134 #define ABSPRI(w) ((w)->priority - EV_MINPRI)
135
136 typedef struct ev_watcher *W;
137 typedef struct ev_watcher_list *WL;
138 typedef struct ev_watcher_time *WT;
139
140 static int have_monotonic; /* did clock_gettime (CLOCK_MONOTONIC) work? */
141
142 /*****************************************************************************/
143
144 typedef struct
145 {
146 struct ev_watcher_list *head;
147 unsigned char events;
148 unsigned char reify;
149 } ANFD;
150
151 typedef struct
152 {
153 W w;
154 int events;
155 } ANPENDING;
156
157 #if EV_MULTIPLICITY
158
159 struct ev_loop
160 {
161 # define VAR(name,decl) decl;
162 # include "ev_vars.h"
163 };
164 # undef VAR
165 # include "ev_wrap.h"
166
167 #else
168
169 # define VAR(name,decl) static decl;
170 # include "ev_vars.h"
171 # undef VAR
172
173 #endif
174
175 /*****************************************************************************/
176
177 inline ev_tstamp
178 ev_time (void)
179 {
180 #if EV_USE_REALTIME
181 struct timespec ts;
182 clock_gettime (CLOCK_REALTIME, &ts);
183 return ts.tv_sec + ts.tv_nsec * 1e-9;
184 #else
185 struct timeval tv;
186 gettimeofday (&tv, 0);
187 return tv.tv_sec + tv.tv_usec * 1e-6;
188 #endif
189 }
190
191 inline ev_tstamp
192 get_clock (void)
193 {
194 #if EV_USE_MONOTONIC
195 if (expect_true (have_monotonic))
196 {
197 struct timespec ts;
198 clock_gettime (CLOCK_MONOTONIC, &ts);
199 return ts.tv_sec + ts.tv_nsec * 1e-9;
200 }
201 #endif
202
203 return ev_time ();
204 }
205
206 ev_tstamp
207 ev_now (EV_P)
208 {
209 return rt_now;
210 }
211
212 #define array_roundsize(base,n) ((n) | 4 & ~3)
213
214 #define array_needsize(base,cur,cnt,init) \
215 if (expect_false ((cnt) > cur)) \
216 { \
217 int newcnt = cur; \
218 do \
219 { \
220 newcnt = array_roundsize (base, newcnt << 1); \
221 } \
222 while ((cnt) > newcnt); \
223 \
224 base = realloc (base, sizeof (*base) * (newcnt)); \
225 init (base + cur, newcnt - cur); \
226 cur = newcnt; \
227 }
228
229 /*****************************************************************************/
230
231 static void
232 anfds_init (ANFD *base, int count)
233 {
234 while (count--)
235 {
236 base->head = 0;
237 base->events = EV_NONE;
238 base->reify = 0;
239
240 ++base;
241 }
242 }
243
244 static void
245 event (EV_P_ W w, int events)
246 {
247 if (w->pending)
248 {
249 pendings [ABSPRI (w)][w->pending - 1].events |= events;
250 return;
251 }
252
253 w->pending = ++pendingcnt [ABSPRI (w)];
254 array_needsize (pendings [ABSPRI (w)], pendingmax [ABSPRI (w)], pendingcnt [ABSPRI (w)], );
255 pendings [ABSPRI (w)][w->pending - 1].w = w;
256 pendings [ABSPRI (w)][w->pending - 1].events = events;
257 }
258
259 static void
260 queue_events (EV_P_ W *events, int eventcnt, int type)
261 {
262 int i;
263
264 for (i = 0; i < eventcnt; ++i)
265 event (EV_A_ events [i], type);
266 }
267
268 static void
269 fd_event (EV_P_ int fd, int events)
270 {
271 ANFD *anfd = anfds + fd;
272 struct ev_io *w;
273
274 for (w = (struct ev_io *)anfd->head; w; w = (struct ev_io *)((WL)w)->next)
275 {
276 int ev = w->events & events;
277
278 if (ev)
279 event (EV_A_ (W)w, ev);
280 }
281 }
282
283 /*****************************************************************************/
284
285 static void
286 fd_reify (EV_P)
287 {
288 int i;
289
290 for (i = 0; i < fdchangecnt; ++i)
291 {
292 int fd = fdchanges [i];
293 ANFD *anfd = anfds + fd;
294 struct ev_io *w;
295
296 int events = 0;
297
298 for (w = (struct ev_io *)anfd->head; w; w = (struct ev_io *)((WL)w)->next)
299 events |= w->events;
300
301 anfd->reify = 0;
302
303 if (anfd->events != events)
304 {
305 method_modify (EV_A_ fd, anfd->events, events);
306 anfd->events = events;
307 }
308 }
309
310 fdchangecnt = 0;
311 }
312
313 static void
314 fd_change (EV_P_ int fd)
315 {
316 if (anfds [fd].reify || fdchangecnt < 0)
317 return;
318
319 anfds [fd].reify = 1;
320
321 ++fdchangecnt;
322 array_needsize (fdchanges, fdchangemax, fdchangecnt, );
323 fdchanges [fdchangecnt - 1] = fd;
324 }
325
326 static void
327 fd_kill (EV_P_ int fd)
328 {
329 struct ev_io *w;
330
331 while ((w = (struct ev_io *)anfds [fd].head))
332 {
333 ev_io_stop (EV_A_ w);
334 event (EV_A_ (W)w, EV_ERROR | EV_READ | EV_WRITE);
335 }
336 }
337
338 /* called on EBADF to verify fds */
339 static void
340 fd_ebadf (EV_P)
341 {
342 int fd;
343
344 for (fd = 0; fd < anfdmax; ++fd)
345 if (anfds [fd].events)
346 if (fcntl (fd, F_GETFD) == -1 && errno == EBADF)
347 fd_kill (EV_A_ fd);
348 }
349
350 /* called on ENOMEM in select/poll to kill some fds and retry */
351 static void
352 fd_enomem (EV_P)
353 {
354 int fd = anfdmax;
355
356 while (fd--)
357 if (anfds [fd].events)
358 {
359 close (fd);
360 fd_kill (EV_A_ fd);
361 return;
362 }
363 }
364
365 /* susually called after fork if method needs to re-arm all fds from scratch */
366 static void
367 fd_rearm_all (EV_P)
368 {
369 int fd;
370
371 /* this should be highly optimised to not do anything but set a flag */
372 for (fd = 0; fd < anfdmax; ++fd)
373 if (anfds [fd].events)
374 {
375 anfds [fd].events = 0;
376 fd_change (EV_A_ fd);
377 }
378 }
379
380 /*****************************************************************************/
381
382 static void
383 upheap (WT *heap, int k)
384 {
385 WT w = heap [k];
386
387 while (k && heap [k >> 1]->at > w->at)
388 {
389 heap [k] = heap [k >> 1];
390 heap [k]->active = k + 1;
391 k >>= 1;
392 }
393
394 heap [k] = w;
395 heap [k]->active = k + 1;
396
397 }
398
399 static void
400 downheap (WT *heap, int N, int k)
401 {
402 WT w = heap [k];
403
404 while (k < (N >> 1))
405 {
406 int j = k << 1;
407
408 if (j + 1 < N && heap [j]->at > heap [j + 1]->at)
409 ++j;
410
411 if (w->at <= heap [j]->at)
412 break;
413
414 heap [k] = heap [j];
415 heap [k]->active = k + 1;
416 k = j;
417 }
418
419 heap [k] = w;
420 heap [k]->active = k + 1;
421 }
422
423 /*****************************************************************************/
424
425 typedef struct
426 {
427 struct ev_watcher_list *head;
428 sig_atomic_t volatile gotsig;
429 } ANSIG;
430
431 static ANSIG *signals;
432 static int signalmax;
433
434 static int sigpipe [2];
435 static sig_atomic_t volatile gotsig;
436 static struct ev_io sigev;
437
438 static void
439 signals_init (ANSIG *base, int count)
440 {
441 while (count--)
442 {
443 base->head = 0;
444 base->gotsig = 0;
445
446 ++base;
447 }
448 }
449
450 static void
451 sighandler (int signum)
452 {
453 signals [signum - 1].gotsig = 1;
454
455 if (!gotsig)
456 {
457 int old_errno = errno;
458 gotsig = 1;
459 write (sigpipe [1], &signum, 1);
460 errno = old_errno;
461 }
462 }
463
464 static void
465 sigcb (EV_P_ struct ev_io *iow, int revents)
466 {
467 struct ev_watcher_list *w;
468 int signum;
469
470 read (sigpipe [0], &revents, 1);
471 gotsig = 0;
472
473 for (signum = signalmax; signum--; )
474 if (signals [signum].gotsig)
475 {
476 signals [signum].gotsig = 0;
477
478 for (w = signals [signum].head; w; w = w->next)
479 event (EV_A_ (W)w, EV_SIGNAL);
480 }
481 }
482
483 static void
484 siginit (EV_P)
485 {
486 #ifndef WIN32
487 fcntl (sigpipe [0], F_SETFD, FD_CLOEXEC);
488 fcntl (sigpipe [1], F_SETFD, FD_CLOEXEC);
489
490 /* rather than sort out wether we really need nb, set it */
491 fcntl (sigpipe [0], F_SETFL, O_NONBLOCK);
492 fcntl (sigpipe [1], F_SETFL, O_NONBLOCK);
493 #endif
494
495 ev_io_set (&sigev, sigpipe [0], EV_READ);
496 ev_io_start (EV_A_ &sigev);
497 ev_unref (EV_A); /* child watcher should not keep loop alive */
498 }
499
500 /*****************************************************************************/
501
502 #ifndef WIN32
503
504 static struct ev_child *childs [PID_HASHSIZE];
505 static struct ev_signal childev;
506
507 #ifndef WCONTINUED
508 # define WCONTINUED 0
509 #endif
510
511 static void
512 child_reap (EV_P_ struct ev_signal *sw, int chain, int pid, int status)
513 {
514 struct ev_child *w;
515
516 for (w = (struct ev_child *)childs [chain & (PID_HASHSIZE - 1)]; w; w = (struct ev_child *)((WL)w)->next)
517 if (w->pid == pid || !w->pid)
518 {
519 w->priority = sw->priority; /* need to do it *now* */
520 w->rpid = pid;
521 w->rstatus = status;
522 event (EV_A_ (W)w, EV_CHILD);
523 }
524 }
525
526 static void
527 childcb (EV_P_ struct ev_signal *sw, int revents)
528 {
529 int pid, status;
530
531 if (0 < (pid = waitpid (-1, &status, WNOHANG | WUNTRACED | WCONTINUED)))
532 {
533 /* make sure we are called again until all childs have been reaped */
534 event (EV_A_ (W)sw, EV_SIGNAL);
535
536 child_reap (EV_A_ sw, pid, pid, status);
537 child_reap (EV_A_ sw, 0, pid, status); /* this might trigger a watcher twice, but event catches that */
538 }
539 }
540
541 #endif
542
543 /*****************************************************************************/
544
545 #if EV_USE_KQUEUE
546 # include "ev_kqueue.c"
547 #endif
548 #if EV_USE_EPOLL
549 # include "ev_epoll.c"
550 #endif
551 #if EV_USE_POLL
552 # include "ev_poll.c"
553 #endif
554 #if EV_USE_SELECT
555 # include "ev_select.c"
556 #endif
557
558 int
559 ev_version_major (void)
560 {
561 return EV_VERSION_MAJOR;
562 }
563
564 int
565 ev_version_minor (void)
566 {
567 return EV_VERSION_MINOR;
568 }
569
570 /* return true if we are running with elevated privileges and should ignore env variables */
571 static int
572 enable_secure (void)
573 {
574 #ifdef WIN32
575 return 0;
576 #else
577 return getuid () != geteuid ()
578 || getgid () != getegid ();
579 #endif
580 }
581
582 int
583 ev_method (EV_P)
584 {
585 return method;
586 }
587
588 static void
589 loop_init (EV_P_ int methods)
590 {
591 if (!method)
592 {
593 #if EV_USE_MONOTONIC
594 {
595 struct timespec ts;
596 if (!clock_gettime (CLOCK_MONOTONIC, &ts))
597 have_monotonic = 1;
598 }
599 #endif
600
601 rt_now = ev_time ();
602 mn_now = get_clock ();
603 now_floor = mn_now;
604 rtmn_diff = rt_now - mn_now;
605
606 if (methods == EVMETHOD_AUTO)
607 if (!enable_secure () && getenv ("LIBEV_METHODS"))
608 methods = atoi (getenv ("LIBEV_METHODS"));
609 else
610 methods = EVMETHOD_ANY;
611
612 method = 0;
613 #if EV_USE_KQUEUE
614 if (!method && (methods & EVMETHOD_KQUEUE)) method = kqueue_init (EV_A_ methods);
615 #endif
616 #if EV_USE_EPOLL
617 if (!method && (methods & EVMETHOD_EPOLL )) method = epoll_init (EV_A_ methods);
618 #endif
619 #if EV_USE_POLL
620 if (!method && (methods & EVMETHOD_POLL )) method = poll_init (EV_A_ methods);
621 #endif
622 #if EV_USE_SELECT
623 if (!method && (methods & EVMETHOD_SELECT)) method = select_init (EV_A_ methods);
624 #endif
625 }
626 }
627
628 void
629 loop_destroy (EV_P)
630 {
631 #if EV_USE_KQUEUE
632 if (method == EVMETHOD_KQUEUE) kqueue_destroy (EV_A);
633 #endif
634 #if EV_USE_EPOLL
635 if (method == EVMETHOD_EPOLL ) epoll_destroy (EV_A);
636 #endif
637 #if EV_USE_POLL
638 if (method == EVMETHOD_POLL ) poll_destroy (EV_A);
639 #endif
640 #if EV_USE_SELECT
641 if (method == EVMETHOD_SELECT) select_destroy (EV_A);
642 #endif
643
644 method = 0;
645 /*TODO*/
646 }
647
648 void
649 loop_fork (EV_P)
650 {
651 /*TODO*/
652 #if EV_USE_EPOLL
653 if (method == EVMETHOD_EPOLL ) epoll_fork (EV_A);
654 #endif
655 #if EV_USE_KQUEUE
656 if (method == EVMETHOD_KQUEUE) kqueue_fork (EV_A);
657 #endif
658 }
659
660 #if EV_MULTIPLICITY
661 struct ev_loop *
662 ev_loop_new (int methods)
663 {
664 struct ev_loop *loop = (struct ev_loop *)calloc (1, sizeof (struct ev_loop));
665
666 loop_init (EV_A_ methods);
667
668 if (ev_method (EV_A))
669 return loop;
670
671 return 0;
672 }
673
674 void
675 ev_loop_destroy (EV_P)
676 {
677 loop_destroy (EV_A);
678 free (loop);
679 }
680
681 void
682 ev_loop_fork (EV_P)
683 {
684 loop_fork (EV_A);
685 }
686
687 #endif
688
689 #if EV_MULTIPLICITY
690 struct ev_loop default_loop_struct;
691 static struct ev_loop *default_loop;
692
693 struct ev_loop *
694 #else
695 static int default_loop;
696
697 int
698 #endif
699 ev_default_loop (int methods)
700 {
701 if (sigpipe [0] == sigpipe [1])
702 if (pipe (sigpipe))
703 return 0;
704
705 if (!default_loop)
706 {
707 #if EV_MULTIPLICITY
708 struct ev_loop *loop = default_loop = &default_loop_struct;
709 #else
710 default_loop = 1;
711 #endif
712
713 loop_init (EV_A_ methods);
714
715 if (ev_method (EV_A))
716 {
717 ev_watcher_init (&sigev, sigcb);
718 ev_set_priority (&sigev, EV_MAXPRI);
719 siginit (EV_A);
720
721 #ifndef WIN32
722 ev_signal_init (&childev, childcb, SIGCHLD);
723 ev_set_priority (&childev, EV_MAXPRI);
724 ev_signal_start (EV_A_ &childev);
725 ev_unref (EV_A); /* child watcher should not keep loop alive */
726 #endif
727 }
728 else
729 default_loop = 0;
730 }
731
732 return default_loop;
733 }
734
735 void
736 ev_default_destroy (void)
737 {
738 #if EV_MULTIPLICITY
739 struct ev_loop *loop = default_loop;
740 #endif
741
742 ev_ref (EV_A); /* child watcher */
743 ev_signal_stop (EV_A_ &childev);
744
745 ev_ref (EV_A); /* signal watcher */
746 ev_io_stop (EV_A_ &sigev);
747
748 close (sigpipe [0]); sigpipe [0] = 0;
749 close (sigpipe [1]); sigpipe [1] = 0;
750
751 loop_destroy (EV_A);
752 }
753
754 void
755 ev_default_fork (void)
756 {
757 #if EV_MULTIPLICITY
758 struct ev_loop *loop = default_loop;
759 #endif
760
761 loop_fork (EV_A);
762
763 ev_io_stop (EV_A_ &sigev);
764 close (sigpipe [0]);
765 close (sigpipe [1]);
766 pipe (sigpipe);
767
768 ev_ref (EV_A); /* signal watcher */
769 siginit (EV_A);
770 }
771
772 /*****************************************************************************/
773
774 static void
775 call_pending (EV_P)
776 {
777 int pri;
778
779 for (pri = NUMPRI; pri--; )
780 while (pendingcnt [pri])
781 {
782 ANPENDING *p = pendings [pri] + --pendingcnt [pri];
783
784 if (p->w)
785 {
786 p->w->pending = 0;
787 p->w->cb (EV_A_ p->w, p->events);
788 }
789 }
790 }
791
792 static void
793 timers_reify (EV_P)
794 {
795 while (timercnt && timers [0]->at <= mn_now)
796 {
797 struct ev_timer *w = timers [0];
798
799 assert (("inactive timer on timer heap detected", ev_is_active (w)));
800
801 /* first reschedule or stop timer */
802 if (w->repeat)
803 {
804 assert (("negative ev_timer repeat value found while processing timers", w->repeat > 0.));
805 w->at = mn_now + w->repeat;
806 downheap ((WT *)timers, timercnt, 0);
807 }
808 else
809 ev_timer_stop (EV_A_ w); /* nonrepeating: stop timer */
810
811 event (EV_A_ (W)w, EV_TIMEOUT);
812 }
813 }
814
815 static void
816 periodics_reify (EV_P)
817 {
818 while (periodiccnt && periodics [0]->at <= rt_now)
819 {
820 struct ev_periodic *w = periodics [0];
821
822 assert (("inactive timer on periodic heap detected", ev_is_active (w)));
823
824 /* first reschedule or stop timer */
825 if (w->interval)
826 {
827 w->at += floor ((rt_now - w->at) / w->interval + 1.) * w->interval;
828 assert (("ev_periodic timeout in the past detected while processing timers, negative interval?", w->at > rt_now));
829 downheap ((WT *)periodics, periodiccnt, 0);
830 }
831 else
832 ev_periodic_stop (EV_A_ w); /* nonrepeating: stop timer */
833
834 event (EV_A_ (W)w, EV_PERIODIC);
835 }
836 }
837
838 static void
839 periodics_reschedule (EV_P)
840 {
841 int i;
842
843 /* adjust periodics after time jump */
844 for (i = 0; i < periodiccnt; ++i)
845 {
846 struct ev_periodic *w = periodics [i];
847
848 if (w->interval)
849 {
850 ev_tstamp diff = ceil ((rt_now - w->at) / w->interval) * w->interval;
851
852 if (fabs (diff) >= 1e-4)
853 {
854 ev_periodic_stop (EV_A_ w);
855 ev_periodic_start (EV_A_ w);
856
857 i = 0; /* restart loop, inefficient, but time jumps should be rare */
858 }
859 }
860 }
861 }
862
863 inline int
864 time_update_monotonic (EV_P)
865 {
866 mn_now = get_clock ();
867
868 if (expect_true (mn_now - now_floor < MIN_TIMEJUMP * .5))
869 {
870 rt_now = rtmn_diff + mn_now;
871 return 0;
872 }
873 else
874 {
875 now_floor = mn_now;
876 rt_now = ev_time ();
877 return 1;
878 }
879 }
880
881 static void
882 time_update (EV_P)
883 {
884 int i;
885
886 #if EV_USE_MONOTONIC
887 if (expect_true (have_monotonic))
888 {
889 if (time_update_monotonic (EV_A))
890 {
891 ev_tstamp odiff = rtmn_diff;
892
893 for (i = 4; --i; ) /* loop a few times, before making important decisions */
894 {
895 rtmn_diff = rt_now - mn_now;
896
897 if (fabs (odiff - rtmn_diff) < MIN_TIMEJUMP)
898 return; /* all is well */
899
900 rt_now = ev_time ();
901 mn_now = get_clock ();
902 now_floor = mn_now;
903 }
904
905 periodics_reschedule (EV_A);
906 /* no timer adjustment, as the monotonic clock doesn't jump */
907 /* timers_reschedule (EV_A_ rtmn_diff - odiff) */
908 }
909 }
910 else
911 #endif
912 {
913 rt_now = ev_time ();
914
915 if (expect_false (mn_now > rt_now || mn_now < rt_now - MAX_BLOCKTIME - MIN_TIMEJUMP))
916 {
917 periodics_reschedule (EV_A);
918
919 /* adjust timers. this is easy, as the offset is the same for all */
920 for (i = 0; i < timercnt; ++i)
921 timers [i]->at += rt_now - mn_now;
922 }
923
924 mn_now = rt_now;
925 }
926 }
927
928 void
929 ev_ref (EV_P)
930 {
931 ++activecnt;
932 }
933
934 void
935 ev_unref (EV_P)
936 {
937 --activecnt;
938 }
939
940 static int loop_done;
941
942 void
943 ev_loop (EV_P_ int flags)
944 {
945 double block;
946 loop_done = flags & (EVLOOP_ONESHOT | EVLOOP_NONBLOCK) ? 1 : 0;
947
948 do
949 {
950 /* queue check watchers (and execute them) */
951 if (expect_false (preparecnt))
952 {
953 queue_events (EV_A_ (W *)prepares, preparecnt, EV_PREPARE);
954 call_pending (EV_A);
955 }
956
957 /* update fd-related kernel structures */
958 fd_reify (EV_A);
959
960 /* calculate blocking time */
961
962 /* we only need this for !monotonic clockor timers, but as we basically
963 always have timers, we just calculate it always */
964 #if EV_USE_MONOTONIC
965 if (expect_true (have_monotonic))
966 time_update_monotonic (EV_A);
967 else
968 #endif
969 {
970 rt_now = ev_time ();
971 mn_now = rt_now;
972 }
973
974 if (flags & EVLOOP_NONBLOCK || idlecnt)
975 block = 0.;
976 else
977 {
978 block = MAX_BLOCKTIME;
979
980 if (timercnt)
981 {
982 ev_tstamp to = timers [0]->at - mn_now + method_fudge;
983 if (block > to) block = to;
984 }
985
986 if (periodiccnt)
987 {
988 ev_tstamp to = periodics [0]->at - rt_now + method_fudge;
989 if (block > to) block = to;
990 }
991
992 if (block < 0.) block = 0.;
993 }
994
995 method_poll (EV_A_ block);
996
997 /* update rt_now, do magic */
998 time_update (EV_A);
999
1000 /* queue pending timers and reschedule them */
1001 timers_reify (EV_A); /* relative timers called last */
1002 periodics_reify (EV_A); /* absolute timers called first */
1003
1004 /* queue idle watchers unless io or timers are pending */
1005 if (!pendingcnt)
1006 queue_events (EV_A_ (W *)idles, idlecnt, EV_IDLE);
1007
1008 /* queue check watchers, to be executed first */
1009 if (checkcnt)
1010 queue_events (EV_A_ (W *)checks, checkcnt, EV_CHECK);
1011
1012 call_pending (EV_A);
1013 }
1014 while (activecnt && !loop_done);
1015
1016 if (loop_done != 2)
1017 loop_done = 0;
1018 }
1019
1020 void
1021 ev_unloop (EV_P_ int how)
1022 {
1023 loop_done = how;
1024 }
1025
1026 /*****************************************************************************/
1027
1028 inline void
1029 wlist_add (WL *head, WL elem)
1030 {
1031 elem->next = *head;
1032 *head = elem;
1033 }
1034
1035 inline void
1036 wlist_del (WL *head, WL elem)
1037 {
1038 while (*head)
1039 {
1040 if (*head == elem)
1041 {
1042 *head = elem->next;
1043 return;
1044 }
1045
1046 head = &(*head)->next;
1047 }
1048 }
1049
1050 inline void
1051 ev_clear_pending (EV_P_ W w)
1052 {
1053 if (w->pending)
1054 {
1055 pendings [ABSPRI (w)][w->pending - 1].w = 0;
1056 w->pending = 0;
1057 }
1058 }
1059
1060 inline void
1061 ev_start (EV_P_ W w, int active)
1062 {
1063 if (w->priority < EV_MINPRI) w->priority = EV_MINPRI;
1064 if (w->priority > EV_MAXPRI) w->priority = EV_MAXPRI;
1065
1066 w->active = active;
1067 ev_ref (EV_A);
1068 }
1069
1070 inline void
1071 ev_stop (EV_P_ W w)
1072 {
1073 ev_unref (EV_A);
1074 w->active = 0;
1075 }
1076
1077 /*****************************************************************************/
1078
1079 void
1080 ev_io_start (EV_P_ struct ev_io *w)
1081 {
1082 int fd = w->fd;
1083
1084 if (ev_is_active (w))
1085 return;
1086
1087 assert (("ev_io_start called with negative fd", fd >= 0));
1088
1089 ev_start (EV_A_ (W)w, 1);
1090 array_needsize (anfds, anfdmax, fd + 1, anfds_init);
1091 wlist_add ((WL *)&anfds[fd].head, (WL)w);
1092
1093 fd_change (EV_A_ fd);
1094 }
1095
1096 void
1097 ev_io_stop (EV_P_ struct ev_io *w)
1098 {
1099 ev_clear_pending (EV_A_ (W)w);
1100 if (!ev_is_active (w))
1101 return;
1102
1103 wlist_del ((WL *)&anfds[w->fd].head, (WL)w);
1104 ev_stop (EV_A_ (W)w);
1105
1106 fd_change (EV_A_ w->fd);
1107 }
1108
1109 void
1110 ev_timer_start (EV_P_ struct ev_timer *w)
1111 {
1112 if (ev_is_active (w))
1113 return;
1114
1115 w->at += mn_now;
1116
1117 assert (("ev_timer_start called with negative timer repeat value", w->repeat >= 0.));
1118
1119 ev_start (EV_A_ (W)w, ++timercnt);
1120 array_needsize (timers, timermax, timercnt, );
1121 timers [timercnt - 1] = w;
1122 upheap ((WT *)timers, timercnt - 1);
1123 }
1124
1125 void
1126 ev_timer_stop (EV_P_ struct ev_timer *w)
1127 {
1128 ev_clear_pending (EV_A_ (W)w);
1129 if (!ev_is_active (w))
1130 return;
1131
1132 if (w->active < timercnt--)
1133 {
1134 timers [w->active - 1] = timers [timercnt];
1135 downheap ((WT *)timers, timercnt, w->active - 1);
1136 }
1137
1138 w->at = w->repeat;
1139
1140 ev_stop (EV_A_ (W)w);
1141 }
1142
1143 void
1144 ev_timer_again (EV_P_ struct ev_timer *w)
1145 {
1146 if (ev_is_active (w))
1147 {
1148 if (w->repeat)
1149 {
1150 w->at = mn_now + w->repeat;
1151 downheap ((WT *)timers, timercnt, w->active - 1);
1152 }
1153 else
1154 ev_timer_stop (EV_A_ w);
1155 }
1156 else if (w->repeat)
1157 ev_timer_start (EV_A_ w);
1158 }
1159
1160 void
1161 ev_periodic_start (EV_P_ struct ev_periodic *w)
1162 {
1163 if (ev_is_active (w))
1164 return;
1165
1166 assert (("ev_periodic_start called with negative interval value", w->interval >= 0.));
1167
1168 /* this formula differs from the one in periodic_reify because we do not always round up */
1169 if (w->interval)
1170 w->at += ceil ((rt_now - w->at) / w->interval) * w->interval;
1171
1172 ev_start (EV_A_ (W)w, ++periodiccnt);
1173 array_needsize (periodics, periodicmax, periodiccnt, );
1174 periodics [periodiccnt - 1] = w;
1175 upheap ((WT *)periodics, periodiccnt - 1);
1176 }
1177
1178 void
1179 ev_periodic_stop (EV_P_ struct ev_periodic *w)
1180 {
1181 ev_clear_pending (EV_A_ (W)w);
1182 if (!ev_is_active (w))
1183 return;
1184
1185 if (w->active < periodiccnt--)
1186 {
1187 periodics [w->active - 1] = periodics [periodiccnt];
1188 downheap ((WT *)periodics, periodiccnt, w->active - 1);
1189 }
1190
1191 ev_stop (EV_A_ (W)w);
1192 }
1193
1194 void
1195 ev_idle_start (EV_P_ struct ev_idle *w)
1196 {
1197 if (ev_is_active (w))
1198 return;
1199
1200 ev_start (EV_A_ (W)w, ++idlecnt);
1201 array_needsize (idles, idlemax, idlecnt, );
1202 idles [idlecnt - 1] = w;
1203 }
1204
1205 void
1206 ev_idle_stop (EV_P_ struct ev_idle *w)
1207 {
1208 ev_clear_pending (EV_A_ (W)w);
1209 if (ev_is_active (w))
1210 return;
1211
1212 idles [w->active - 1] = idles [--idlecnt];
1213 ev_stop (EV_A_ (W)w);
1214 }
1215
1216 void
1217 ev_prepare_start (EV_P_ struct ev_prepare *w)
1218 {
1219 if (ev_is_active (w))
1220 return;
1221
1222 ev_start (EV_A_ (W)w, ++preparecnt);
1223 array_needsize (prepares, preparemax, preparecnt, );
1224 prepares [preparecnt - 1] = w;
1225 }
1226
1227 void
1228 ev_prepare_stop (EV_P_ struct ev_prepare *w)
1229 {
1230 ev_clear_pending (EV_A_ (W)w);
1231 if (ev_is_active (w))
1232 return;
1233
1234 prepares [w->active - 1] = prepares [--preparecnt];
1235 ev_stop (EV_A_ (W)w);
1236 }
1237
1238 void
1239 ev_check_start (EV_P_ struct ev_check *w)
1240 {
1241 if (ev_is_active (w))
1242 return;
1243
1244 ev_start (EV_A_ (W)w, ++checkcnt);
1245 array_needsize (checks, checkmax, checkcnt, );
1246 checks [checkcnt - 1] = w;
1247 }
1248
1249 void
1250 ev_check_stop (EV_P_ struct ev_check *w)
1251 {
1252 ev_clear_pending (EV_A_ (W)w);
1253 if (ev_is_active (w))
1254 return;
1255
1256 checks [w->active - 1] = checks [--checkcnt];
1257 ev_stop (EV_A_ (W)w);
1258 }
1259
1260 #ifndef SA_RESTART
1261 # define SA_RESTART 0
1262 #endif
1263
1264 void
1265 ev_signal_start (EV_P_ struct ev_signal *w)
1266 {
1267 #if EV_MULTIPLICITY
1268 assert (("signal watchers are only supported in the default loop", loop == default_loop));
1269 #endif
1270 if (ev_is_active (w))
1271 return;
1272
1273 assert (("ev_signal_start called with illegal signal number", w->signum > 0));
1274
1275 ev_start (EV_A_ (W)w, 1);
1276 array_needsize (signals, signalmax, w->signum, signals_init);
1277 wlist_add ((WL *)&signals [w->signum - 1].head, (WL)w);
1278
1279 if (!w->next)
1280 {
1281 struct sigaction sa;
1282 sa.sa_handler = sighandler;
1283 sigfillset (&sa.sa_mask);
1284 sa.sa_flags = SA_RESTART; /* if restarting works we save one iteration */
1285 sigaction (w->signum, &sa, 0);
1286 }
1287 }
1288
1289 void
1290 ev_signal_stop (EV_P_ struct ev_signal *w)
1291 {
1292 ev_clear_pending (EV_A_ (W)w);
1293 if (!ev_is_active (w))
1294 return;
1295
1296 wlist_del ((WL *)&signals [w->signum - 1].head, (WL)w);
1297 ev_stop (EV_A_ (W)w);
1298
1299 if (!signals [w->signum - 1].head)
1300 signal (w->signum, SIG_DFL);
1301 }
1302
1303 void
1304 ev_child_start (EV_P_ struct ev_child *w)
1305 {
1306 #if EV_MULTIPLICITY
1307 assert (("child watchers are only supported in the default loop", loop == default_loop));
1308 #endif
1309 if (ev_is_active (w))
1310 return;
1311
1312 ev_start (EV_A_ (W)w, 1);
1313 wlist_add ((WL *)&childs [w->pid & (PID_HASHSIZE - 1)], (WL)w);
1314 }
1315
1316 void
1317 ev_child_stop (EV_P_ struct ev_child *w)
1318 {
1319 ev_clear_pending (EV_A_ (W)w);
1320 if (ev_is_active (w))
1321 return;
1322
1323 wlist_del ((WL *)&childs [w->pid & (PID_HASHSIZE - 1)], (WL)w);
1324 ev_stop (EV_A_ (W)w);
1325 }
1326
1327 /*****************************************************************************/
1328
1329 struct ev_once
1330 {
1331 struct ev_io io;
1332 struct ev_timer to;
1333 void (*cb)(int revents, void *arg);
1334 void *arg;
1335 };
1336
1337 static void
1338 once_cb (EV_P_ struct ev_once *once, int revents)
1339 {
1340 void (*cb)(int revents, void *arg) = once->cb;
1341 void *arg = once->arg;
1342
1343 ev_io_stop (EV_A_ &once->io);
1344 ev_timer_stop (EV_A_ &once->to);
1345 free (once);
1346
1347 cb (revents, arg);
1348 }
1349
1350 static void
1351 once_cb_io (EV_P_ struct ev_io *w, int revents)
1352 {
1353 once_cb (EV_A_ (struct ev_once *)(((char *)w) - offsetof (struct ev_once, io)), revents);
1354 }
1355
1356 static void
1357 once_cb_to (EV_P_ struct ev_timer *w, int revents)
1358 {
1359 once_cb (EV_A_ (struct ev_once *)(((char *)w) - offsetof (struct ev_once, to)), revents);
1360 }
1361
1362 void
1363 ev_once (EV_P_ int fd, int events, ev_tstamp timeout, void (*cb)(int revents, void *arg), void *arg)
1364 {
1365 struct ev_once *once = malloc (sizeof (struct ev_once));
1366
1367 if (!once)
1368 cb (EV_ERROR | EV_READ | EV_WRITE | EV_TIMEOUT, arg);
1369 else
1370 {
1371 once->cb = cb;
1372 once->arg = arg;
1373
1374 ev_watcher_init (&once->io, once_cb_io);
1375 if (fd >= 0)
1376 {
1377 ev_io_set (&once->io, fd, events);
1378 ev_io_start (EV_A_ &once->io);
1379 }
1380
1381 ev_watcher_init (&once->to, once_cb_to);
1382 if (timeout >= 0.)
1383 {
1384 ev_timer_set (&once->to, timeout, 0.);
1385 ev_timer_start (EV_A_ &once->to);
1386 }
1387 }
1388 }
1389