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Revision: 1.70
Committed: Tue Nov 6 00:52:32 2007 UTC (16 years, 6 months ago) by root
Content type: text/plain
Branch: MAIN
Changes since 1.69: +38 -22 lines
Log Message:
better fork

File Contents

# 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_WIN32
98 # ifdef WIN32
99 # define EV_USE_WIN32 1
100 # else
101 # define EV_USE_WIN32 0
102 # endif
103 #endif
104
105 #ifndef EV_USE_REALTIME
106 # define EV_USE_REALTIME 1
107 #endif
108
109 /**/
110
111 #ifndef CLOCK_MONOTONIC
112 # undef EV_USE_MONOTONIC
113 # define EV_USE_MONOTONIC 0
114 #endif
115
116 #ifndef CLOCK_REALTIME
117 # undef EV_USE_REALTIME
118 # define EV_USE_REALTIME 0
119 #endif
120
121 /**/
122
123 #define MIN_TIMEJUMP 1. /* minimum timejump that gets detected (if monotonic clock available) */
124 #define MAX_BLOCKTIME 59.731 /* never wait longer than this time (to detect time jumps) */
125 #define PID_HASHSIZE 16 /* size of pid hash table, must be power of two */
126 /*#define CLEANUP_INTERVAL 300. /* how often to try to free memory and re-check fds */
127
128 #include "ev.h"
129
130 #if __GNUC__ >= 3
131 # define expect(expr,value) __builtin_expect ((expr),(value))
132 # define inline inline
133 #else
134 # define expect(expr,value) (expr)
135 # define inline static
136 #endif
137
138 #define expect_false(expr) expect ((expr) != 0, 0)
139 #define expect_true(expr) expect ((expr) != 0, 1)
140
141 #define NUMPRI (EV_MAXPRI - EV_MINPRI + 1)
142 #define ABSPRI(w) ((w)->priority - EV_MINPRI)
143
144 typedef struct ev_watcher *W;
145 typedef struct ev_watcher_list *WL;
146 typedef struct ev_watcher_time *WT;
147
148 static int have_monotonic; /* did clock_gettime (CLOCK_MONOTONIC) work? */
149
150 #if WIN32
151 /* note: the comment below could not be substantiated, but what would I care */
152 /* MSDN says this is required to handle SIGFPE */
153 volatile double SIGFPE_REQ = 0.0f;
154 #endif
155
156 /*****************************************************************************/
157
158 static void (*syserr_cb)(const char *msg);
159
160 void ev_set_syserr_cb (void (*cb)(const char *msg))
161 {
162 syserr_cb = cb;
163 }
164
165 static void
166 syserr (const char *msg)
167 {
168 if (!msg)
169 msg = "(libev) system error";
170
171 if (syserr_cb)
172 syserr_cb (msg);
173 else
174 {
175 perror (msg);
176 abort ();
177 }
178 }
179
180 static void *(*alloc)(void *ptr, long size);
181
182 void ev_set_allocator (void *(*cb)(void *ptr, long size))
183 {
184 alloc = cb;
185 }
186
187 static void *
188 ev_realloc (void *ptr, long size)
189 {
190 ptr = alloc ? alloc (ptr, size) : realloc (ptr, size);
191
192 if (!ptr && size)
193 {
194 fprintf (stderr, "libev: cannot allocate %ld bytes, aborting.", size);
195 abort ();
196 }
197
198 return ptr;
199 }
200
201 #define ev_malloc(size) ev_realloc (0, (size))
202 #define ev_free(ptr) ev_realloc ((ptr), 0)
203
204 /*****************************************************************************/
205
206 typedef struct
207 {
208 WL head;
209 unsigned char events;
210 unsigned char reify;
211 } ANFD;
212
213 typedef struct
214 {
215 W w;
216 int events;
217 } ANPENDING;
218
219 #if EV_MULTIPLICITY
220
221 struct ev_loop
222 {
223 # define VAR(name,decl) decl;
224 # include "ev_vars.h"
225 };
226 # undef VAR
227 # include "ev_wrap.h"
228
229 #else
230
231 # define VAR(name,decl) static decl;
232 # include "ev_vars.h"
233 # undef VAR
234
235 #endif
236
237 /*****************************************************************************/
238
239 inline ev_tstamp
240 ev_time (void)
241 {
242 #if EV_USE_REALTIME
243 struct timespec ts;
244 clock_gettime (CLOCK_REALTIME, &ts);
245 return ts.tv_sec + ts.tv_nsec * 1e-9;
246 #else
247 struct timeval tv;
248 gettimeofday (&tv, 0);
249 return tv.tv_sec + tv.tv_usec * 1e-6;
250 #endif
251 }
252
253 inline ev_tstamp
254 get_clock (void)
255 {
256 #if EV_USE_MONOTONIC
257 if (expect_true (have_monotonic))
258 {
259 struct timespec ts;
260 clock_gettime (CLOCK_MONOTONIC, &ts);
261 return ts.tv_sec + ts.tv_nsec * 1e-9;
262 }
263 #endif
264
265 return ev_time ();
266 }
267
268 ev_tstamp
269 ev_now (EV_P)
270 {
271 return rt_now;
272 }
273
274 #define array_roundsize(base,n) ((n) | 4 & ~3)
275
276 #define array_needsize(base,cur,cnt,init) \
277 if (expect_false ((cnt) > cur)) \
278 { \
279 int newcnt = cur; \
280 do \
281 { \
282 newcnt = array_roundsize (base, newcnt << 1); \
283 } \
284 while ((cnt) > newcnt); \
285 \
286 base = ev_realloc (base, sizeof (*base) * (newcnt)); \
287 init (base + cur, newcnt - cur); \
288 cur = newcnt; \
289 }
290
291 #define array_slim(stem) \
292 if (stem ## max < array_roundsize (stem ## cnt >> 2)) \
293 { \
294 stem ## max = array_roundsize (stem ## cnt >> 1); \
295 base = ev_realloc (base, sizeof (*base) * (stem ## max)); \
296 fprintf (stderr, "slimmed down " # stem " to %d\n", stem ## max);/*D*/\
297 }
298
299 #define array_free(stem, idx) \
300 ev_free (stem ## s idx); stem ## cnt idx = stem ## max idx = 0;
301
302 /*****************************************************************************/
303
304 static void
305 anfds_init (ANFD *base, int count)
306 {
307 while (count--)
308 {
309 base->head = 0;
310 base->events = EV_NONE;
311 base->reify = 0;
312
313 ++base;
314 }
315 }
316
317 static void
318 event (EV_P_ W w, int events)
319 {
320 if (w->pending)
321 {
322 pendings [ABSPRI (w)][w->pending - 1].events |= events;
323 return;
324 }
325
326 w->pending = ++pendingcnt [ABSPRI (w)];
327 array_needsize (pendings [ABSPRI (w)], pendingmax [ABSPRI (w)], pendingcnt [ABSPRI (w)], );
328 pendings [ABSPRI (w)][w->pending - 1].w = w;
329 pendings [ABSPRI (w)][w->pending - 1].events = events;
330 }
331
332 static void
333 queue_events (EV_P_ W *events, int eventcnt, int type)
334 {
335 int i;
336
337 for (i = 0; i < eventcnt; ++i)
338 event (EV_A_ events [i], type);
339 }
340
341 static void
342 fd_event (EV_P_ int fd, int events)
343 {
344 ANFD *anfd = anfds + fd;
345 struct ev_io *w;
346
347 for (w = (struct ev_io *)anfd->head; w; w = (struct ev_io *)((WL)w)->next)
348 {
349 int ev = w->events & events;
350
351 if (ev)
352 event (EV_A_ (W)w, ev);
353 }
354 }
355
356 /*****************************************************************************/
357
358 static void
359 fd_reify (EV_P)
360 {
361 int i;
362
363 for (i = 0; i < fdchangecnt; ++i)
364 {
365 int fd = fdchanges [i];
366 ANFD *anfd = anfds + fd;
367 struct ev_io *w;
368
369 int events = 0;
370
371 for (w = (struct ev_io *)anfd->head; w; w = (struct ev_io *)((WL)w)->next)
372 events |= w->events;
373
374 anfd->reify = 0;
375
376 method_modify (EV_A_ fd, anfd->events, events);
377 anfd->events = events;
378 }
379
380 fdchangecnt = 0;
381 }
382
383 static void
384 fd_change (EV_P_ int fd)
385 {
386 if (anfds [fd].reify)
387 return;
388
389 anfds [fd].reify = 1;
390
391 ++fdchangecnt;
392 array_needsize (fdchanges, fdchangemax, fdchangecnt, );
393 fdchanges [fdchangecnt - 1] = fd;
394 }
395
396 static void
397 fd_kill (EV_P_ int fd)
398 {
399 struct ev_io *w;
400
401 while ((w = (struct ev_io *)anfds [fd].head))
402 {
403 ev_io_stop (EV_A_ w);
404 event (EV_A_ (W)w, EV_ERROR | EV_READ | EV_WRITE);
405 }
406 }
407
408 /* called on EBADF to verify fds */
409 static void
410 fd_ebadf (EV_P)
411 {
412 int fd;
413
414 for (fd = 0; fd < anfdmax; ++fd)
415 if (anfds [fd].events)
416 if (fcntl (fd, F_GETFD) == -1 && errno == EBADF)
417 fd_kill (EV_A_ fd);
418 }
419
420 /* called on ENOMEM in select/poll to kill some fds and retry */
421 static void
422 fd_enomem (EV_P)
423 {
424 int fd;
425
426 for (fd = anfdmax; fd--; )
427 if (anfds [fd].events)
428 {
429 fd_kill (EV_A_ fd);
430 return;
431 }
432 }
433
434 /* usually called after fork if method needs to re-arm all fds from scratch */
435 static void
436 fd_rearm_all (EV_P)
437 {
438 int fd;
439
440 /* this should be highly optimised to not do anything but set a flag */
441 for (fd = 0; fd < anfdmax; ++fd)
442 if (anfds [fd].events)
443 {
444 anfds [fd].events = 0;
445 fd_change (EV_A_ fd);
446 }
447 }
448
449 /*****************************************************************************/
450
451 static void
452 upheap (WT *heap, int k)
453 {
454 WT w = heap [k];
455
456 while (k && heap [k >> 1]->at > w->at)
457 {
458 heap [k] = heap [k >> 1];
459 ((W)heap [k])->active = k + 1;
460 k >>= 1;
461 }
462
463 heap [k] = w;
464 ((W)heap [k])->active = k + 1;
465
466 }
467
468 static void
469 downheap (WT *heap, int N, int k)
470 {
471 WT w = heap [k];
472
473 while (k < (N >> 1))
474 {
475 int j = k << 1;
476
477 if (j + 1 < N && heap [j]->at > heap [j + 1]->at)
478 ++j;
479
480 if (w->at <= heap [j]->at)
481 break;
482
483 heap [k] = heap [j];
484 ((W)heap [k])->active = k + 1;
485 k = j;
486 }
487
488 heap [k] = w;
489 ((W)heap [k])->active = k + 1;
490 }
491
492 /*****************************************************************************/
493
494 typedef struct
495 {
496 WL head;
497 sig_atomic_t volatile gotsig;
498 } ANSIG;
499
500 static ANSIG *signals;
501 static int signalmax;
502
503 static int sigpipe [2];
504 static sig_atomic_t volatile gotsig;
505 static struct ev_io sigev;
506
507 static void
508 signals_init (ANSIG *base, int count)
509 {
510 while (count--)
511 {
512 base->head = 0;
513 base->gotsig = 0;
514
515 ++base;
516 }
517 }
518
519 static void
520 sighandler (int signum)
521 {
522 #if WIN32
523 signal (signum, sighandler);
524 #endif
525
526 signals [signum - 1].gotsig = 1;
527
528 if (!gotsig)
529 {
530 int old_errno = errno;
531 gotsig = 1;
532 write (sigpipe [1], &signum, 1);
533 errno = old_errno;
534 }
535 }
536
537 static void
538 sigcb (EV_P_ struct ev_io *iow, int revents)
539 {
540 WL w;
541 int signum;
542
543 read (sigpipe [0], &revents, 1);
544 gotsig = 0;
545
546 for (signum = signalmax; signum--; )
547 if (signals [signum].gotsig)
548 {
549 signals [signum].gotsig = 0;
550
551 for (w = signals [signum].head; w; w = w->next)
552 event (EV_A_ (W)w, EV_SIGNAL);
553 }
554 }
555
556 static void
557 siginit (EV_P)
558 {
559 #ifndef WIN32
560 fcntl (sigpipe [0], F_SETFD, FD_CLOEXEC);
561 fcntl (sigpipe [1], F_SETFD, FD_CLOEXEC);
562
563 /* rather than sort out wether we really need nb, set it */
564 fcntl (sigpipe [0], F_SETFL, O_NONBLOCK);
565 fcntl (sigpipe [1], F_SETFL, O_NONBLOCK);
566 #endif
567
568 ev_io_set (&sigev, sigpipe [0], EV_READ);
569 ev_io_start (EV_A_ &sigev);
570 ev_unref (EV_A); /* child watcher should not keep loop alive */
571 }
572
573 /*****************************************************************************/
574
575 #ifndef WIN32
576
577 static struct ev_child *childs [PID_HASHSIZE];
578 static struct ev_signal childev;
579
580 #ifndef WCONTINUED
581 # define WCONTINUED 0
582 #endif
583
584 static void
585 child_reap (EV_P_ struct ev_signal *sw, int chain, int pid, int status)
586 {
587 struct ev_child *w;
588
589 for (w = (struct ev_child *)childs [chain & (PID_HASHSIZE - 1)]; w; w = (struct ev_child *)((WL)w)->next)
590 if (w->pid == pid || !w->pid)
591 {
592 ev_priority (w) = ev_priority (sw); /* need to do it *now* */
593 w->rpid = pid;
594 w->rstatus = status;
595 event (EV_A_ (W)w, EV_CHILD);
596 }
597 }
598
599 static void
600 childcb (EV_P_ struct ev_signal *sw, int revents)
601 {
602 int pid, status;
603
604 if (0 < (pid = waitpid (-1, &status, WNOHANG | WUNTRACED | WCONTINUED)))
605 {
606 /* make sure we are called again until all childs have been reaped */
607 event (EV_A_ (W)sw, EV_SIGNAL);
608
609 child_reap (EV_A_ sw, pid, pid, status);
610 child_reap (EV_A_ sw, 0, pid, status); /* this might trigger a watcher twice, but event catches that */
611 }
612 }
613
614 #endif
615
616 /*****************************************************************************/
617
618 #if EV_USE_KQUEUE
619 # include "ev_kqueue.c"
620 #endif
621 #if EV_USE_EPOLL
622 # include "ev_epoll.c"
623 #endif
624 #if EV_USE_POLL
625 # include "ev_poll.c"
626 #endif
627 #if EV_USE_SELECT
628 # include "ev_select.c"
629 #endif
630
631 int
632 ev_version_major (void)
633 {
634 return EV_VERSION_MAJOR;
635 }
636
637 int
638 ev_version_minor (void)
639 {
640 return EV_VERSION_MINOR;
641 }
642
643 /* return true if we are running with elevated privileges and should ignore env variables */
644 static int
645 enable_secure (void)
646 {
647 #ifdef WIN32
648 return 0;
649 #else
650 return getuid () != geteuid ()
651 || getgid () != getegid ();
652 #endif
653 }
654
655 int
656 ev_method (EV_P)
657 {
658 return method;
659 }
660
661 static void
662 loop_init (EV_P_ int methods)
663 {
664 if (!method)
665 {
666 #if EV_USE_MONOTONIC
667 {
668 struct timespec ts;
669 if (!clock_gettime (CLOCK_MONOTONIC, &ts))
670 have_monotonic = 1;
671 }
672 #endif
673
674 rt_now = ev_time ();
675 mn_now = get_clock ();
676 now_floor = mn_now;
677 rtmn_diff = rt_now - mn_now;
678
679 if (methods == EVMETHOD_AUTO)
680 if (!enable_secure () && getenv ("LIBEV_METHODS"))
681 methods = atoi (getenv ("LIBEV_METHODS"));
682 else
683 methods = EVMETHOD_ANY;
684
685 method = 0;
686 #if EV_USE_WIN32
687 if (!method && (methods & EVMETHOD_WIN32 )) method = win32_init (EV_A_ methods);
688 #endif
689 #if EV_USE_KQUEUE
690 if (!method && (methods & EVMETHOD_KQUEUE)) method = kqueue_init (EV_A_ methods);
691 #endif
692 #if EV_USE_EPOLL
693 if (!method && (methods & EVMETHOD_EPOLL )) method = epoll_init (EV_A_ methods);
694 #endif
695 #if EV_USE_POLL
696 if (!method && (methods & EVMETHOD_POLL )) method = poll_init (EV_A_ methods);
697 #endif
698 #if EV_USE_SELECT
699 if (!method && (methods & EVMETHOD_SELECT)) method = select_init (EV_A_ methods);
700 #endif
701
702 ev_watcher_init (&sigev, sigcb);
703 ev_set_priority (&sigev, EV_MAXPRI);
704 }
705 }
706
707 void
708 loop_destroy (EV_P)
709 {
710 int i;
711
712 #if EV_USE_WIN32
713 if (method == EVMETHOD_WIN32 ) win32_destroy (EV_A);
714 #endif
715 #if EV_USE_KQUEUE
716 if (method == EVMETHOD_KQUEUE) kqueue_destroy (EV_A);
717 #endif
718 #if EV_USE_EPOLL
719 if (method == EVMETHOD_EPOLL ) epoll_destroy (EV_A);
720 #endif
721 #if EV_USE_POLL
722 if (method == EVMETHOD_POLL ) poll_destroy (EV_A);
723 #endif
724 #if EV_USE_SELECT
725 if (method == EVMETHOD_SELECT) select_destroy (EV_A);
726 #endif
727
728 for (i = NUMPRI; i--; )
729 array_free (pending, [i]);
730
731 array_free (fdchange, );
732 array_free (timer, );
733 array_free (periodic, );
734 array_free (idle, );
735 array_free (prepare, );
736 array_free (check, );
737
738 method = 0;
739 }
740
741 static void
742 loop_fork (EV_P)
743 {
744 #if EV_USE_EPOLL
745 if (method == EVMETHOD_EPOLL ) epoll_fork (EV_A);
746 #endif
747 #if EV_USE_KQUEUE
748 if (method == EVMETHOD_KQUEUE) kqueue_fork (EV_A);
749 #endif
750
751 if (ev_is_active (&sigev))
752 {
753 /* default loop */
754
755 ev_ref (EV_A);
756 ev_io_stop (EV_A_ &sigev);
757 close (sigpipe [0]);
758 close (sigpipe [1]);
759
760 while (pipe (sigpipe))
761 syserr ("(libev) error creating pipe");
762
763 siginit (EV_A);
764 }
765
766 postfork = 0;
767 }
768
769 #if EV_MULTIPLICITY
770 struct ev_loop *
771 ev_loop_new (int methods)
772 {
773 struct ev_loop *loop = (struct ev_loop *)ev_malloc (sizeof (struct ev_loop));
774
775 memset (loop, 0, sizeof (struct ev_loop));
776
777 loop_init (EV_A_ methods);
778
779 if (ev_method (EV_A))
780 return loop;
781
782 return 0;
783 }
784
785 void
786 ev_loop_destroy (EV_P)
787 {
788 loop_destroy (EV_A);
789 ev_free (loop);
790 }
791
792 void
793 ev_loop_fork (EV_P)
794 {
795 postfork = 1;
796 }
797
798 #endif
799
800 #if EV_MULTIPLICITY
801 struct ev_loop default_loop_struct;
802 static struct ev_loop *default_loop;
803
804 struct ev_loop *
805 #else
806 static int default_loop;
807
808 int
809 #endif
810 ev_default_loop (int methods)
811 {
812 if (sigpipe [0] == sigpipe [1])
813 if (pipe (sigpipe))
814 return 0;
815
816 if (!default_loop)
817 {
818 #if EV_MULTIPLICITY
819 struct ev_loop *loop = default_loop = &default_loop_struct;
820 #else
821 default_loop = 1;
822 #endif
823
824 loop_init (EV_A_ methods);
825
826 if (ev_method (EV_A))
827 {
828 siginit (EV_A);
829
830 #ifndef WIN32
831 ev_signal_init (&childev, childcb, SIGCHLD);
832 ev_set_priority (&childev, EV_MAXPRI);
833 ev_signal_start (EV_A_ &childev);
834 ev_unref (EV_A); /* child watcher should not keep loop alive */
835 #endif
836 }
837 else
838 default_loop = 0;
839 }
840
841 return default_loop;
842 }
843
844 void
845 ev_default_destroy (void)
846 {
847 #if EV_MULTIPLICITY
848 struct ev_loop *loop = default_loop;
849 #endif
850
851 ev_ref (EV_A); /* child watcher */
852 ev_signal_stop (EV_A_ &childev);
853
854 ev_ref (EV_A); /* signal watcher */
855 ev_io_stop (EV_A_ &sigev);
856
857 close (sigpipe [0]); sigpipe [0] = 0;
858 close (sigpipe [1]); sigpipe [1] = 0;
859
860 loop_destroy (EV_A);
861 }
862
863 void
864 ev_default_fork (void)
865 {
866 #if EV_MULTIPLICITY
867 struct ev_loop *loop = default_loop;
868 #endif
869
870 if (method)
871 postfork = 1;
872 }
873
874 /*****************************************************************************/
875
876 static void
877 call_pending (EV_P)
878 {
879 int pri;
880
881 for (pri = NUMPRI; pri--; )
882 while (pendingcnt [pri])
883 {
884 ANPENDING *p = pendings [pri] + --pendingcnt [pri];
885
886 if (p->w)
887 {
888 p->w->pending = 0;
889 p->w->cb (EV_A_ p->w, p->events);
890 }
891 }
892 }
893
894 static void
895 timers_reify (EV_P)
896 {
897 while (timercnt && ((WT)timers [0])->at <= mn_now)
898 {
899 struct ev_timer *w = timers [0];
900
901 assert (("inactive timer on timer heap detected", ev_is_active (w)));
902
903 /* first reschedule or stop timer */
904 if (w->repeat)
905 {
906 assert (("negative ev_timer repeat value found while processing timers", w->repeat > 0.));
907 ((WT)w)->at = mn_now + w->repeat;
908 downheap ((WT *)timers, timercnt, 0);
909 }
910 else
911 ev_timer_stop (EV_A_ w); /* nonrepeating: stop timer */
912
913 event (EV_A_ (W)w, EV_TIMEOUT);
914 }
915 }
916
917 static void
918 periodics_reify (EV_P)
919 {
920 while (periodiccnt && ((WT)periodics [0])->at <= rt_now)
921 {
922 struct ev_periodic *w = periodics [0];
923
924 assert (("inactive timer on periodic heap detected", ev_is_active (w)));
925
926 /* first reschedule or stop timer */
927 if (w->interval)
928 {
929 ((WT)w)->at += floor ((rt_now - ((WT)w)->at) / w->interval + 1.) * w->interval;
930 assert (("ev_periodic timeout in the past detected while processing timers, negative interval?", ((WT)w)->at > rt_now));
931 downheap ((WT *)periodics, periodiccnt, 0);
932 }
933 else
934 ev_periodic_stop (EV_A_ w); /* nonrepeating: stop timer */
935
936 event (EV_A_ (W)w, EV_PERIODIC);
937 }
938 }
939
940 static void
941 periodics_reschedule (EV_P)
942 {
943 int i;
944
945 /* adjust periodics after time jump */
946 for (i = 0; i < periodiccnt; ++i)
947 {
948 struct ev_periodic *w = periodics [i];
949
950 if (w->interval)
951 {
952 ev_tstamp diff = ceil ((rt_now - ((WT)w)->at) / w->interval) * w->interval;
953
954 if (fabs (diff) >= 1e-4)
955 {
956 ev_periodic_stop (EV_A_ w);
957 ev_periodic_start (EV_A_ w);
958
959 i = 0; /* restart loop, inefficient, but time jumps should be rare */
960 }
961 }
962 }
963 }
964
965 inline int
966 time_update_monotonic (EV_P)
967 {
968 mn_now = get_clock ();
969
970 if (expect_true (mn_now - now_floor < MIN_TIMEJUMP * .5))
971 {
972 rt_now = rtmn_diff + mn_now;
973 return 0;
974 }
975 else
976 {
977 now_floor = mn_now;
978 rt_now = ev_time ();
979 return 1;
980 }
981 }
982
983 static void
984 time_update (EV_P)
985 {
986 int i;
987
988 #if EV_USE_MONOTONIC
989 if (expect_true (have_monotonic))
990 {
991 if (time_update_monotonic (EV_A))
992 {
993 ev_tstamp odiff = rtmn_diff;
994
995 for (i = 4; --i; ) /* loop a few times, before making important decisions */
996 {
997 rtmn_diff = rt_now - mn_now;
998
999 if (fabs (odiff - rtmn_diff) < MIN_TIMEJUMP)
1000 return; /* all is well */
1001
1002 rt_now = ev_time ();
1003 mn_now = get_clock ();
1004 now_floor = mn_now;
1005 }
1006
1007 periodics_reschedule (EV_A);
1008 /* no timer adjustment, as the monotonic clock doesn't jump */
1009 /* timers_reschedule (EV_A_ rtmn_diff - odiff) */
1010 }
1011 }
1012 else
1013 #endif
1014 {
1015 rt_now = ev_time ();
1016
1017 if (expect_false (mn_now > rt_now || mn_now < rt_now - MAX_BLOCKTIME - MIN_TIMEJUMP))
1018 {
1019 periodics_reschedule (EV_A);
1020
1021 /* adjust timers. this is easy, as the offset is the same for all */
1022 for (i = 0; i < timercnt; ++i)
1023 ((WT)timers [i])->at += rt_now - mn_now;
1024 }
1025
1026 mn_now = rt_now;
1027 }
1028 }
1029
1030 void
1031 ev_ref (EV_P)
1032 {
1033 ++activecnt;
1034 }
1035
1036 void
1037 ev_unref (EV_P)
1038 {
1039 --activecnt;
1040 }
1041
1042 static int loop_done;
1043
1044 void
1045 ev_loop (EV_P_ int flags)
1046 {
1047 double block;
1048 loop_done = flags & (EVLOOP_ONESHOT | EVLOOP_NONBLOCK) ? 1 : 0;
1049
1050 do
1051 {
1052 /* queue check watchers (and execute them) */
1053 if (expect_false (preparecnt))
1054 {
1055 queue_events (EV_A_ (W *)prepares, preparecnt, EV_PREPARE);
1056 call_pending (EV_A);
1057 }
1058
1059 /* we might have forked, so reify kernel state if necessary */
1060 if (expect_false (postfork))
1061 loop_fork (EV_A);
1062
1063 /* update fd-related kernel structures */
1064 fd_reify (EV_A);
1065
1066 /* calculate blocking time */
1067
1068 /* we only need this for !monotonic clockor timers, but as we basically
1069 always have timers, we just calculate it always */
1070 #if EV_USE_MONOTONIC
1071 if (expect_true (have_monotonic))
1072 time_update_monotonic (EV_A);
1073 else
1074 #endif
1075 {
1076 rt_now = ev_time ();
1077 mn_now = rt_now;
1078 }
1079
1080 if (flags & EVLOOP_NONBLOCK || idlecnt)
1081 block = 0.;
1082 else
1083 {
1084 block = MAX_BLOCKTIME;
1085
1086 if (timercnt)
1087 {
1088 ev_tstamp to = ((WT)timers [0])->at - mn_now + method_fudge;
1089 if (block > to) block = to;
1090 }
1091
1092 if (periodiccnt)
1093 {
1094 ev_tstamp to = ((WT)periodics [0])->at - rt_now + method_fudge;
1095 if (block > to) block = to;
1096 }
1097
1098 if (block < 0.) block = 0.;
1099 }
1100
1101 method_poll (EV_A_ block);
1102
1103 /* update rt_now, do magic */
1104 time_update (EV_A);
1105
1106 /* queue pending timers and reschedule them */
1107 timers_reify (EV_A); /* relative timers called last */
1108 periodics_reify (EV_A); /* absolute timers called first */
1109
1110 /* queue idle watchers unless io or timers are pending */
1111 if (!pendingcnt)
1112 queue_events (EV_A_ (W *)idles, idlecnt, EV_IDLE);
1113
1114 /* queue check watchers, to be executed first */
1115 if (checkcnt)
1116 queue_events (EV_A_ (W *)checks, checkcnt, EV_CHECK);
1117
1118 call_pending (EV_A);
1119 }
1120 while (activecnt && !loop_done);
1121
1122 if (loop_done != 2)
1123 loop_done = 0;
1124 }
1125
1126 void
1127 ev_unloop (EV_P_ int how)
1128 {
1129 loop_done = how;
1130 }
1131
1132 /*****************************************************************************/
1133
1134 inline void
1135 wlist_add (WL *head, WL elem)
1136 {
1137 elem->next = *head;
1138 *head = elem;
1139 }
1140
1141 inline void
1142 wlist_del (WL *head, WL elem)
1143 {
1144 while (*head)
1145 {
1146 if (*head == elem)
1147 {
1148 *head = elem->next;
1149 return;
1150 }
1151
1152 head = &(*head)->next;
1153 }
1154 }
1155
1156 inline void
1157 ev_clear_pending (EV_P_ W w)
1158 {
1159 if (w->pending)
1160 {
1161 pendings [ABSPRI (w)][w->pending - 1].w = 0;
1162 w->pending = 0;
1163 }
1164 }
1165
1166 inline void
1167 ev_start (EV_P_ W w, int active)
1168 {
1169 if (w->priority < EV_MINPRI) w->priority = EV_MINPRI;
1170 if (w->priority > EV_MAXPRI) w->priority = EV_MAXPRI;
1171
1172 w->active = active;
1173 ev_ref (EV_A);
1174 }
1175
1176 inline void
1177 ev_stop (EV_P_ W w)
1178 {
1179 ev_unref (EV_A);
1180 w->active = 0;
1181 }
1182
1183 /*****************************************************************************/
1184
1185 void
1186 ev_io_start (EV_P_ struct ev_io *w)
1187 {
1188 int fd = w->fd;
1189
1190 if (ev_is_active (w))
1191 return;
1192
1193 assert (("ev_io_start called with negative fd", fd >= 0));
1194
1195 ev_start (EV_A_ (W)w, 1);
1196 array_needsize (anfds, anfdmax, fd + 1, anfds_init);
1197 wlist_add ((WL *)&anfds[fd].head, (WL)w);
1198
1199 fd_change (EV_A_ fd);
1200 }
1201
1202 void
1203 ev_io_stop (EV_P_ struct ev_io *w)
1204 {
1205 ev_clear_pending (EV_A_ (W)w);
1206 if (!ev_is_active (w))
1207 return;
1208
1209 wlist_del ((WL *)&anfds[w->fd].head, (WL)w);
1210 ev_stop (EV_A_ (W)w);
1211
1212 fd_change (EV_A_ w->fd);
1213 }
1214
1215 void
1216 ev_timer_start (EV_P_ struct ev_timer *w)
1217 {
1218 if (ev_is_active (w))
1219 return;
1220
1221 ((WT)w)->at += mn_now;
1222
1223 assert (("ev_timer_start called with negative timer repeat value", w->repeat >= 0.));
1224
1225 ev_start (EV_A_ (W)w, ++timercnt);
1226 array_needsize (timers, timermax, timercnt, );
1227 timers [timercnt - 1] = w;
1228 upheap ((WT *)timers, timercnt - 1);
1229
1230 assert (("internal timer heap corruption", timers [((W)w)->active - 1] == w));
1231 }
1232
1233 void
1234 ev_timer_stop (EV_P_ struct ev_timer *w)
1235 {
1236 ev_clear_pending (EV_A_ (W)w);
1237 if (!ev_is_active (w))
1238 return;
1239
1240 assert (("internal timer heap corruption", timers [((W)w)->active - 1] == w));
1241
1242 if (((W)w)->active < timercnt--)
1243 {
1244 timers [((W)w)->active - 1] = timers [timercnt];
1245 downheap ((WT *)timers, timercnt, ((W)w)->active - 1);
1246 }
1247
1248 ((WT)w)->at = w->repeat;
1249
1250 ev_stop (EV_A_ (W)w);
1251 }
1252
1253 void
1254 ev_timer_again (EV_P_ struct ev_timer *w)
1255 {
1256 if (ev_is_active (w))
1257 {
1258 if (w->repeat)
1259 {
1260 ((WT)w)->at = mn_now + w->repeat;
1261 downheap ((WT *)timers, timercnt, ((W)w)->active - 1);
1262 }
1263 else
1264 ev_timer_stop (EV_A_ w);
1265 }
1266 else if (w->repeat)
1267 ev_timer_start (EV_A_ w);
1268 }
1269
1270 void
1271 ev_periodic_start (EV_P_ struct ev_periodic *w)
1272 {
1273 if (ev_is_active (w))
1274 return;
1275
1276 assert (("ev_periodic_start called with negative interval value", w->interval >= 0.));
1277
1278 /* this formula differs from the one in periodic_reify because we do not always round up */
1279 if (w->interval)
1280 ((WT)w)->at += ceil ((rt_now - ((WT)w)->at) / w->interval) * w->interval;
1281
1282 ev_start (EV_A_ (W)w, ++periodiccnt);
1283 array_needsize (periodics, periodicmax, periodiccnt, );
1284 periodics [periodiccnt - 1] = w;
1285 upheap ((WT *)periodics, periodiccnt - 1);
1286
1287 assert (("internal periodic heap corruption", periodics [((W)w)->active - 1] == w));
1288 }
1289
1290 void
1291 ev_periodic_stop (EV_P_ struct ev_periodic *w)
1292 {
1293 ev_clear_pending (EV_A_ (W)w);
1294 if (!ev_is_active (w))
1295 return;
1296
1297 assert (("internal periodic heap corruption", periodics [((W)w)->active - 1] == w));
1298
1299 if (((W)w)->active < periodiccnt--)
1300 {
1301 periodics [((W)w)->active - 1] = periodics [periodiccnt];
1302 downheap ((WT *)periodics, periodiccnt, ((W)w)->active - 1);
1303 }
1304
1305 ev_stop (EV_A_ (W)w);
1306 }
1307
1308 void
1309 ev_idle_start (EV_P_ struct ev_idle *w)
1310 {
1311 if (ev_is_active (w))
1312 return;
1313
1314 ev_start (EV_A_ (W)w, ++idlecnt);
1315 array_needsize (idles, idlemax, idlecnt, );
1316 idles [idlecnt - 1] = w;
1317 }
1318
1319 void
1320 ev_idle_stop (EV_P_ struct ev_idle *w)
1321 {
1322 ev_clear_pending (EV_A_ (W)w);
1323 if (ev_is_active (w))
1324 return;
1325
1326 idles [((W)w)->active - 1] = idles [--idlecnt];
1327 ev_stop (EV_A_ (W)w);
1328 }
1329
1330 void
1331 ev_prepare_start (EV_P_ struct ev_prepare *w)
1332 {
1333 if (ev_is_active (w))
1334 return;
1335
1336 ev_start (EV_A_ (W)w, ++preparecnt);
1337 array_needsize (prepares, preparemax, preparecnt, );
1338 prepares [preparecnt - 1] = w;
1339 }
1340
1341 void
1342 ev_prepare_stop (EV_P_ struct ev_prepare *w)
1343 {
1344 ev_clear_pending (EV_A_ (W)w);
1345 if (ev_is_active (w))
1346 return;
1347
1348 prepares [((W)w)->active - 1] = prepares [--preparecnt];
1349 ev_stop (EV_A_ (W)w);
1350 }
1351
1352 void
1353 ev_check_start (EV_P_ struct ev_check *w)
1354 {
1355 if (ev_is_active (w))
1356 return;
1357
1358 ev_start (EV_A_ (W)w, ++checkcnt);
1359 array_needsize (checks, checkmax, checkcnt, );
1360 checks [checkcnt - 1] = w;
1361 }
1362
1363 void
1364 ev_check_stop (EV_P_ struct ev_check *w)
1365 {
1366 ev_clear_pending (EV_A_ (W)w);
1367 if (ev_is_active (w))
1368 return;
1369
1370 checks [((W)w)->active - 1] = checks [--checkcnt];
1371 ev_stop (EV_A_ (W)w);
1372 }
1373
1374 #ifndef SA_RESTART
1375 # define SA_RESTART 0
1376 #endif
1377
1378 void
1379 ev_signal_start (EV_P_ struct ev_signal *w)
1380 {
1381 #if EV_MULTIPLICITY
1382 assert (("signal watchers are only supported in the default loop", loop == default_loop));
1383 #endif
1384 if (ev_is_active (w))
1385 return;
1386
1387 assert (("ev_signal_start called with illegal signal number", w->signum > 0));
1388
1389 ev_start (EV_A_ (W)w, 1);
1390 array_needsize (signals, signalmax, w->signum, signals_init);
1391 wlist_add ((WL *)&signals [w->signum - 1].head, (WL)w);
1392
1393 if (!((WL)w)->next)
1394 {
1395 #if WIN32
1396 signal (w->signum, sighandler);
1397 #else
1398 struct sigaction sa;
1399 sa.sa_handler = sighandler;
1400 sigfillset (&sa.sa_mask);
1401 sa.sa_flags = SA_RESTART; /* if restarting works we save one iteration */
1402 sigaction (w->signum, &sa, 0);
1403 #endif
1404 }
1405 }
1406
1407 void
1408 ev_signal_stop (EV_P_ struct ev_signal *w)
1409 {
1410 ev_clear_pending (EV_A_ (W)w);
1411 if (!ev_is_active (w))
1412 return;
1413
1414 wlist_del ((WL *)&signals [w->signum - 1].head, (WL)w);
1415 ev_stop (EV_A_ (W)w);
1416
1417 if (!signals [w->signum - 1].head)
1418 signal (w->signum, SIG_DFL);
1419 }
1420
1421 void
1422 ev_child_start (EV_P_ struct ev_child *w)
1423 {
1424 #if EV_MULTIPLICITY
1425 assert (("child watchers are only supported in the default loop", loop == default_loop));
1426 #endif
1427 if (ev_is_active (w))
1428 return;
1429
1430 ev_start (EV_A_ (W)w, 1);
1431 wlist_add ((WL *)&childs [w->pid & (PID_HASHSIZE - 1)], (WL)w);
1432 }
1433
1434 void
1435 ev_child_stop (EV_P_ struct ev_child *w)
1436 {
1437 ev_clear_pending (EV_A_ (W)w);
1438 if (ev_is_active (w))
1439 return;
1440
1441 wlist_del ((WL *)&childs [w->pid & (PID_HASHSIZE - 1)], (WL)w);
1442 ev_stop (EV_A_ (W)w);
1443 }
1444
1445 /*****************************************************************************/
1446
1447 struct ev_once
1448 {
1449 struct ev_io io;
1450 struct ev_timer to;
1451 void (*cb)(int revents, void *arg);
1452 void *arg;
1453 };
1454
1455 static void
1456 once_cb (EV_P_ struct ev_once *once, int revents)
1457 {
1458 void (*cb)(int revents, void *arg) = once->cb;
1459 void *arg = once->arg;
1460
1461 ev_io_stop (EV_A_ &once->io);
1462 ev_timer_stop (EV_A_ &once->to);
1463 ev_free (once);
1464
1465 cb (revents, arg);
1466 }
1467
1468 static void
1469 once_cb_io (EV_P_ struct ev_io *w, int revents)
1470 {
1471 once_cb (EV_A_ (struct ev_once *)(((char *)w) - offsetof (struct ev_once, io)), revents);
1472 }
1473
1474 static void
1475 once_cb_to (EV_P_ struct ev_timer *w, int revents)
1476 {
1477 once_cb (EV_A_ (struct ev_once *)(((char *)w) - offsetof (struct ev_once, to)), revents);
1478 }
1479
1480 void
1481 ev_once (EV_P_ int fd, int events, ev_tstamp timeout, void (*cb)(int revents, void *arg), void *arg)
1482 {
1483 struct ev_once *once = ev_malloc (sizeof (struct ev_once));
1484
1485 if (!once)
1486 cb (EV_ERROR | EV_READ | EV_WRITE | EV_TIMEOUT, arg);
1487 else
1488 {
1489 once->cb = cb;
1490 once->arg = arg;
1491
1492 ev_watcher_init (&once->io, once_cb_io);
1493 if (fd >= 0)
1494 {
1495 ev_io_set (&once->io, fd, events);
1496 ev_io_start (EV_A_ &once->io);
1497 }
1498
1499 ev_watcher_init (&once->to, once_cb_to);
1500 if (timeout >= 0.)
1501 {
1502 ev_timer_set (&once->to, timeout, 0.);
1503 ev_timer_start (EV_A_ &once->to);
1504 }
1505 }
1506 }
1507