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/cvs/libev/ev.c
Revision: 1.1
Committed: Tue Oct 30 20:59:31 2007 UTC (16 years, 6 months ago) by root
Content type: text/plain
Branch: MAIN
Log Message:
initial roguh cut that doesn't immediately barf

File Contents

# User Rev Content
1 root 1.1 #include <math.h>
2     #include <stdlib.h>
3    
4     #include <stdio.h>
5    
6     #include <errno.h>
7     #include <sys/time.h>
8     #include <time.h>
9    
10     #ifdef CLOCK_MONOTONIC
11     # define HAVE_MONOTONIC 1
12     #endif
13    
14     #define HAVE_EPOLL 1
15     #define HAVE_REALTIME 1
16     #define HAVE_SELECT 0
17    
18     #define MAX_BLOCKTIME 60.
19    
20     #include "ev.h"
21    
22     struct ev_watcher {
23     EV_WATCHER (ev_watcher);
24     };
25    
26     struct ev_watcher_list {
27     EV_WATCHER_LIST (ev_watcher_list);
28     };
29    
30     ev_tstamp ev_now;
31     int ev_method;
32    
33     static int have_monotonic; /* runtime */
34    
35     static ev_tstamp method_fudge; /* stupid epoll-returns-early bug */
36     static void (*method_reify)(void);
37     static void (*method_poll)(ev_tstamp timeout);
38    
39     ev_tstamp
40     ev_time (void)
41     {
42     #if HAVE_REALTIME
43     struct timespec ts;
44     clock_gettime (CLOCK_REALTIME, &ts);
45     return ts.tv_sec + ts.tv_nsec * 1e-9;
46     #else
47     struct timeval tv;
48     gettimeofday (&tv, 0);
49     return tv.tv_sec + tv.tv_usec * 1e-6;
50     #endif
51     }
52    
53     static ev_tstamp
54     get_clock (void)
55     {
56     #if HAVE_MONOTONIC
57     if (have_monotonic)
58     {
59     struct timespec ts;
60     clock_gettime (CLOCK_MONOTONIC, &ts);
61     return ts.tv_sec + ts.tv_nsec * 1e-9;
62     }
63     #endif
64    
65     return ev_time ();
66     }
67    
68     #define array_needsize(base,cur,cnt,init) \
69     if ((cnt) > cur) \
70     { \
71     int newcnt = cur; \
72     do \
73     { \
74     newcnt += (newcnt >> 1) + 16; \
75     } \
76     while ((cnt) > newcnt); \
77     fprintf (stderr, "resize(" # base ") from %d to %d\n", cur, newcnt);\
78     base = realloc (base, sizeof (*base) * (newcnt)); \
79     init (base + cur, newcnt - cur); \
80     cur = newcnt; \
81     }
82    
83     typedef struct
84     {
85     struct ev_io *head;
86     unsigned char wev, rev; /* want, received event set */
87     } ANFD;
88    
89     static ANFD *anfds;
90     static int anfdmax;
91    
92     static int *fdchanges;
93     static int fdchangemax, fdchangecnt;
94    
95     static void
96     anfds_init (ANFD *base, int count)
97     {
98     while (count--)
99     {
100     base->head = 0;
101     base->wev = base->rev = EV_NONE;
102     ++base;
103     }
104     }
105    
106     typedef struct
107     {
108     struct ev_watcher *w;
109     int events;
110     } ANPENDING;
111    
112     static ANPENDING *pendings;
113     static int pendingmax, pendingcnt;
114    
115     static void
116     event (struct ev_watcher *w, int events)
117     {
118     w->pending = ++pendingcnt;
119     array_needsize (pendings, pendingmax, pendingcnt, );
120     pendings [pendingcnt - 1].w = w;
121     pendings [pendingcnt - 1].events = events;
122     }
123    
124     static void
125     fd_event (int fd, int events)
126     {
127     ANFD *anfd = anfds + fd;
128     struct ev_io *w;
129    
130     for (w = anfd->head; w; w = w->next)
131     {
132     int ev = w->events & events;
133    
134     if (ev)
135     event ((struct ev_watcher *)w, ev);
136     }
137     }
138    
139     static struct ev_timer **timers;
140     static int timermax, timercnt;
141    
142     static void
143     upheap (int k)
144     {
145     struct ev_timer *w = timers [k];
146    
147     while (k && timers [k >> 1]->at > w->at)
148     {
149     timers [k] = timers [k >> 1];
150     timers [k]->active = k + 1;
151     k >>= 1;
152     }
153    
154     timers [k] = w;
155     timers [k]->active = k + 1;
156    
157     }
158    
159     static void
160     downheap (int k)
161     {
162     struct ev_timer *w = timers [k];
163    
164     while (k <= (timercnt >> 1))
165     {
166     int j = k << 1;
167    
168     if (j + 1 < timercnt && timers [j]->at > timers [j + 1]->at)
169     ++j;
170    
171     if (w->at <= timers [j]->at)
172     break;
173    
174     timers [k] = timers [j];
175     timers [k]->active = k;
176     k = j;
177     }
178    
179     timers [k] = w;
180     timers [k]->active = k + 1;
181     }
182    
183     static struct ev_signal **signals;
184     static int signalmax, signalcnt;
185    
186     static void
187     signals_init (struct ev_signal **base, int count)
188     {
189     while (count--)
190     *base++ = 0;
191     }
192    
193     #if HAVE_EPOLL
194     # include "ev_epoll.c"
195     #endif
196     #if HAVE_SELECT
197     # include "ev_select.c"
198     #endif
199    
200     int ev_init (int flags)
201     {
202     #if HAVE_MONOTONIC
203     {
204     struct timespec ts;
205     if (!clock_gettime (CLOCK_MONOTONIC, &ts))
206     have_monotonic = 1;
207     }
208     #endif
209    
210     ev_now = ev_time ();
211    
212     #if HAVE_EPOLL
213     if (epoll_init (flags))
214     return ev_method;
215     #endif
216     #if HAVE_SELECT
217     if (select_init (flags))
218     return ev_method;
219     #endif
220    
221     ev_method = EVMETHOD_NONE;
222     return ev_method;
223     }
224    
225     void ev_prefork (void)
226     {
227     }
228    
229     void ev_postfork_parent (void)
230     {
231     }
232    
233     void ev_postfork_child (void)
234     {
235     #if HAVE_EPOLL
236     epoll_postfork_child ();
237     #endif
238     }
239    
240     static void
241     call_pending ()
242     {
243     int i;
244    
245     for (i = 0; i < pendingcnt; ++i)
246     {
247     ANPENDING *p = pendings + i;
248    
249     if (p->w)
250     {
251     p->w->pending = 0;
252     p->w->cb (p->w, p->events);
253     }
254     }
255    
256     pendingcnt = 0;
257     }
258    
259     static void
260     timer_reify (void)
261     {
262     while (timercnt && timers [0]->at <= ev_now)
263     {
264     struct ev_timer *w = timers [0];
265    
266     /* first reschedule timer */
267     if (w->repeat)
268     {
269     fprintf (stderr, "a %f now %f repeat %f, %f\n", w->at, ev_now, w->repeat, w->repeat *1e30);//D
270     if (w->is_abs)
271     w->at += floor ((ev_now - w->at) / w->repeat + 1.) * w->repeat;
272     else
273     w->at = ev_now + w->repeat;
274    
275     fprintf (stderr, "b %f\n", w->at);//D
276    
277     downheap (0);
278     }
279     else
280     evtimer_stop (w); /* nonrepeating: stop timer */
281    
282     event ((struct ev_watcher *)w, EV_TIMEOUT);
283     }
284     }
285    
286     int ev_loop_done;
287    
288     int ev_loop (int flags)
289     {
290     double block;
291     ev_loop_done = flags & EVLOOP_ONESHOT;
292    
293     do
294     {
295     /* update fd-related kernel structures */
296     method_reify (); fdchangecnt = 0;
297    
298     /* calculate blocking time */
299     ev_now = ev_time ();
300    
301     if (flags & EVLOOP_NONBLOCK)
302     block = 0.;
303     else if (!timercnt)
304     block = MAX_BLOCKTIME;
305     else
306     {
307     block = timers [0]->at - ev_now + method_fudge;
308     if (block < 0.) block = 0.;
309     else if (block > MAX_BLOCKTIME) block = MAX_BLOCKTIME;
310     }
311    
312     fprintf (stderr, "block %f\n", block);//D
313     method_poll (block);
314    
315     /* put pending timers into pendign queue and reschedule them */
316     timer_reify ();
317    
318     ev_now = ev_time ();
319     call_pending ();
320     }
321     while (!ev_loop_done);
322     }
323    
324     static void
325     wlist_add (struct ev_watcher_list **head, struct ev_watcher_list *elem)
326     {
327     elem->next = *head;
328     *head = elem;
329     }
330    
331     static void
332     wlist_del (struct ev_watcher_list **head, struct ev_watcher_list *elem)
333     {
334     while (*head)
335     {
336     if (*head == elem)
337     {
338     *head = elem->next;
339     return;
340     }
341    
342     head = &(*head)->next;
343     }
344     }
345    
346     static void
347     ev_start (struct ev_watcher *w, int active)
348     {
349     w->pending = 0;
350     w->active = active;
351     }
352    
353     static void
354     ev_stop (struct ev_watcher *w)
355     {
356     if (w->pending)
357     pendings [w->pending - 1].w = 0;
358    
359     w->active = 0;
360     /* nop */
361     }
362    
363     void
364     evio_start (struct ev_io *w)
365     {
366     if (ev_is_active (w))
367     return;
368    
369     int fd = w->fd;
370    
371     ev_start ((struct ev_watcher *)w, 1);
372     array_needsize (anfds, anfdmax, fd + 1, anfds_init);
373     wlist_add ((struct ev_watcher_list **)&anfds[fd].head, (struct ev_watcher_list *)w);
374    
375     ++fdchangecnt;
376     array_needsize (fdchanges, fdchangemax, fdchangecnt, );
377     fdchanges [fdchangecnt - 1] = fd;
378     }
379    
380     void
381     evio_stop (struct ev_io *w)
382     {
383     if (!ev_is_active (w))
384     return;
385    
386     wlist_del ((struct ev_watcher_list **)&anfds[w->fd].head, (struct ev_watcher_list *)w);
387     ev_stop ((struct ev_watcher *)w);
388    
389     ++fdchangecnt;
390     array_needsize (fdchanges, fdchangemax, fdchangecnt, );
391     fdchanges [fdchangecnt - 1] = w->fd;
392     }
393    
394     void
395     evtimer_start (struct ev_timer *w)
396     {
397     if (ev_is_active (w))
398     return;
399    
400     fprintf (stderr, "t1 %f a %d\n", w->at, w->is_abs);//D
401     if (w->is_abs)
402     {
403     if (w->repeat)
404     w->at += ceil ((ev_now - w->at) / w->repeat) * w->repeat;
405     }
406     else
407     w->at += ev_now;
408     fprintf (stderr, "t2 %f a %d\n", w->at, w->is_abs);//D
409    
410     ev_start ((struct ev_watcher *)w, ++timercnt);
411     array_needsize (timers, timermax, timercnt, );
412     timers [timercnt - 1] = w;
413     upheap (timercnt - 1);
414     }
415    
416     void
417     evtimer_stop (struct ev_timer *w)
418     {
419     if (!ev_is_active (w))
420     return;
421    
422     timers [w->active - 1] = timers [--timercnt];
423     downheap (w->active - 1);
424     ev_stop ((struct ev_watcher *)w);
425     }
426    
427     void
428     evsignal_start (struct ev_signal *w)
429     {
430     if (ev_is_active (w))
431     return;
432    
433     ev_start ((struct ev_watcher *)w, 1);
434     array_needsize (signals, signalmax, w->signum, signals_init);
435     wlist_add ((struct ev_watcher_list **)&signals [w->signum - 1], (struct ev_watcher_list *)w);
436     }
437    
438     void
439     evsignal_stop (struct ev_signal *w)
440     {
441     if (!ev_is_active (w))
442     return;
443    
444     wlist_del ((struct ev_watcher_list **)&signals [w->signum - 1], (struct ev_watcher_list *)w);
445     ev_stop ((struct ev_watcher *)w);
446     }
447    
448     /*****************************************************************************/
449     #if 1
450    
451     static void
452     sin_cb (struct ev_io *w, int revents)
453     {
454     fprintf (stderr, "sin %d, revents %d\n", w->fd, revents);
455     }
456    
457     static void
458     ocb (struct ev_timer *w, int revents)
459     {
460     fprintf (stderr, "timer %f,%f (%x) (%f) d%p\n", w->at, w->repeat, revents, w->at - ev_time (), w->data);
461     }
462    
463     int main (void)
464     {
465     struct ev_io sin;
466    
467     ev_init (0);
468    
469     evw_init (&sin, sin_cb, 55);
470     evio_set (&sin, 0, EV_READ);
471     evio_start (&sin);
472    
473     struct ev_timer t1;
474     evw_init (&t1, ocb, 1);
475     evtimer_set_rel (&t1, 1, 0);
476     evtimer_start (&t1);
477    
478     struct ev_timer t2;
479     evw_init (&t2, ocb, 2);
480     evtimer_set_abs (&t2, ev_time () + 2, 0);
481     evtimer_start (&t2);
482    
483     ev_loop (0);
484    
485     return 0;
486     }
487    
488     #endif
489    
490    
491    
492