libev/ev.c

#include <math.h>
#include <stdlib.h>
#include <unistd.h>
#include <fcntl.h>
#include <signal.h>

#include <stdio.h>

#include <assert.h>
#include <errno.h>
#include <sys/time.h>
#include <time.h>

#ifdef CLOCK_MONOTONIC
# define HAVE_MONOTONIC 1
#endif

#define HAVE_REALTIME 1
#define HAVE_EPOLL 1
#define HAVE_SELECT 1

#define MIN_TIMEJUMP  1. /* minimum timejump that gets detected (if monotonic clock available) */
#define MAX_BLOCKTIME 60.

#include "ev.h"

struct ev_watcher {
  EV_WATCHER (ev_watcher);
};

struct ev_watcher_list {
  EV_WATCHER_LIST (ev_watcher_list);
};

static ev_tstamp now, diff; /* monotonic clock */
ev_tstamp ev_now;
int ev_method;

static int have_monotonic; /* runtime */

static ev_tstamp method_fudge; /* stupid epoll-returns-early bug */
static void (*method_modify)(int fd, int oev, int nev);
static void (*method_poll)(ev_tstamp timeout);

ev_tstamp
ev_time (void)
{
#if HAVE_REALTIME
  struct timespec ts;
  clock_gettime (CLOCK_REALTIME, &ts);
  return ts.tv_sec + ts.tv_nsec * 1e-9;
#else
  struct timeval tv;
  gettimeofday (&tv, 0);
  return tv.tv_sec + tv.tv_usec * 1e-6;
#endif
}

static ev_tstamp
get_clock (void)
{
#if HAVE_MONOTONIC
  if (have_monotonic)
    {
      struct timespec ts;
      clock_gettime (CLOCK_MONOTONIC, &ts);
      return ts.tv_sec + ts.tv_nsec * 1e-9;
    }
#endif

  return ev_time ();
}

#define array_needsize(base,cur,cnt,init)               \
  if ((cnt) > cur)                                      \
    {                                                   \
      int newcnt = cur ? cur << 1 : 16;                 \
      fprintf (stderr, "resize(" # base ") from %d to %d\n", cur, newcnt);\
      base = realloc (base, sizeof (*base) * (newcnt)); \
      init (base + cur, newcnt - cur);                  \
      cur = newcnt;                                     \
    }

typedef struct
{
  struct ev_io *head;
  unsigned char wev, rev; /* want, received event set */
} ANFD;

static ANFD *anfds;
static int anfdmax;

static int *fdchanges;
static int fdchangemax, fdchangecnt;

static void
anfds_init (ANFD *base, int count)
{
  while (count--)
    {
      base->head = 0;
      base->wev = base->rev = EV_NONE;
      ++base;
    }
}

typedef struct
{
  struct ev_watcher *w;
  int events;
} ANPENDING;

static ANPENDING *pendings;
static int pendingmax, pendingcnt;

static void
event (struct ev_watcher *w, int events)
{
  w->pending = ++pendingcnt;
  array_needsize (pendings, pendingmax, pendingcnt, );
  pendings [pendingcnt - 1].w      = w;
  pendings [pendingcnt - 1].events = events;
}

static void
fd_event (int fd, int events)
{
  ANFD *anfd = anfds + fd;
  struct ev_io *w;

  for (w = anfd->head; w; w = w->next)
    {
      int ev = w->events & events;

      if (ev)
        event ((struct ev_watcher *)w, ev);
    }
}

static struct ev_timer **atimers;
static int atimermax, atimercnt;

static struct ev_timer **rtimers;
static int rtimermax, rtimercnt;

static void
upheap (struct ev_timer **timers, int k)
{
  struct ev_timer *w = timers [k];

  while (k && timers [k >> 1]->at > w->at)
    {
      timers [k] = timers [k >> 1];
      timers [k]->active = k + 1;
      k >>= 1;
    }

  timers [k] = w;
  timers [k]->active = k + 1;

}

static void
downheap (struct ev_timer **timers, int N, int k)
{
  struct ev_timer *w = timers [k];

  while (k < (N >> 1))
    {
      int j = k << 1;

      if (j + 1 < N && timers [j]->at > timers [j + 1]->at)
        ++j;

      if (w->at <= timers [j]->at)
        break;

      timers [k] = timers [j];
      timers [k]->active = k + 1;
      k = j;
    }

  timers [k] = w;
  timers [k]->active = k + 1;
}

typedef struct
{
  struct ev_signal *head;
  sig_atomic_t gotsig;
} ANSIG;

static ANSIG *signals;
static int signalmax;

static int sigpipe [2];
static sig_atomic_t gotsig;
static struct ev_io sigev;

static void
signals_init (ANSIG *base, int count)
{
  while (count--)
    {
      base->head   = 0;
      base->gotsig = 0;
      ++base;
    }
}

static void
sighandler (int signum)
{
  signals [signum - 1].gotsig = 1;

  if (!gotsig)
    {
      gotsig = 1;
      write (sigpipe [1], &gotsig, 1);
    }
}

static void
sigcb (struct ev_io *iow, int revents)
{
  struct ev_signal *w;
  int sig;

  gotsig = 0;
  read (sigpipe [0], &revents, 1);

  for (sig = signalmax; sig--; )
    if (signals [sig].gotsig)
      {
        signals [sig].gotsig = 0;

        for (w = signals [sig].head; w; w = w->next)
          event ((struct ev_watcher *)w, EV_SIGNAL);
      }
}

static void
siginit (void)
{
  fcntl (sigpipe [0], F_SETFD, FD_CLOEXEC);
  fcntl (sigpipe [1], F_SETFD, FD_CLOEXEC);

  /* rather than sort out wether we really need nb, set it */
  fcntl (sigpipe [0], F_SETFL, O_NONBLOCK);
  fcntl (sigpipe [1], F_SETFL, O_NONBLOCK);

  evio_set (&sigev, sigpipe [0], EV_READ);
  evio_start (&sigev);
}

#if HAVE_EPOLL
# include "ev_epoll.c"
#endif
#if HAVE_SELECT
# include "ev_select.c"
#endif

int ev_init (int flags)
{
#if HAVE_MONOTONIC
  {
    struct timespec ts;
    if (!clock_gettime (CLOCK_MONOTONIC, &ts))
      have_monotonic = 1;
  }
#endif

  ev_now = ev_time ();
  now    = get_clock ();
  diff   = ev_now - now;

  if (pipe (sigpipe))
    return 0;

  ev_method = EVMETHOD_NONE;
#if HAVE_EPOLL
  if (ev_method == EVMETHOD_NONE) epoll_init (flags);
#endif
#if HAVE_SELECT
  if (ev_method == EVMETHOD_NONE) select_init (flags);
#endif

  if (ev_method)
    {
      evw_init (&sigev, sigcb, 0);
      siginit ();
    }

  return ev_method;
}

void ev_prefork (void)
{
}

void ev_postfork_parent (void)
{
}

void ev_postfork_child (void)
{
#if HAVE_EPOLL
  if (ev_method == EVMETHOD_EPOLL)
    epoll_postfork_child ();
#endif

  evio_stop (&sigev);
  close (sigpipe [0]);
  close (sigpipe [1]);
  pipe (sigpipe);
  siginit ();
}

static void
fd_reify (void)
{
  int i;

  for (i = 0; i < fdchangecnt; ++i)
    {
      int fd = fdchanges [i];
      ANFD *anfd = anfds + fd;
      struct ev_io *w;

      int wev = 0;

      for (w = anfd->head; w; w = w->next)
        wev |= w->events;

      if (anfd->wev != wev)
        {
          method_modify (fd, anfd->wev, wev);
          anfd->wev = wev;
        }
    }

  fdchangecnt = 0;
}

static void
call_pending ()
{
  int i;

  for (i = 0; i < pendingcnt; ++i)
    {
      ANPENDING *p = pendings + i;

      if (p->w)
        {
          p->w->pending = 0;
          p->w->cb (p->w, p->events);
        }
    }

  pendingcnt = 0;
}

static void
timers_reify (struct ev_timer **timers, int timercnt, ev_tstamp now)
{
  while (timercnt && timers [0]->at <= now)
    {
      struct ev_timer *w = timers [0];

      /* first reschedule or stop timer */
      if (w->repeat)
        {
          if (w->is_abs)
            w->at += floor ((now - w->at) / w->repeat + 1.) * w->repeat;
          else
            w->at = now + w->repeat;

          assert (w->at > now);

          downheap (timers, timercnt, 0);
        }
      else
        {
          evtimer_stop (w); /* nonrepeating: stop timer */
          --timercnt; /* maybe pass by reference instead? */
        }

      event ((struct ev_watcher *)w, EV_TIMEOUT);
    }
}

static void
time_update ()
{
  int i;
  ev_now = ev_time ();

  if (have_monotonic)
    {
      ev_tstamp odiff = diff;

      /* detecting time jumps is much more difficult */
      for (i = 2; --i; ) /* loop a few times, before making important decisions */
        {
          now = get_clock ();
          diff = ev_now - now;

          if (fabs (odiff - diff) < MIN_TIMEJUMP)
            return; /* all is well */

          ev_now = ev_time ();
        }

      /* time jump detected, reschedule atimers */
      for (i = 0; i < atimercnt; ++i)
        {
          struct ev_timer *w = atimers [i];
          w->at += ceil ((ev_now - w->at) / w->repeat + 1.) * w->repeat;
        }
    }
  else
    {
      if (now > ev_now || now < ev_now - MAX_BLOCKTIME - MIN_TIMEJUMP)
        /* time jump detected, adjust rtimers */
        for (i = 0; i < rtimercnt; ++i)
          rtimers [i]->at += ev_now - now;

      now = ev_now;
    }
}

int ev_loop_done;

void ev_loop (int flags)
{
  double block;
  ev_loop_done = flags & EVLOOP_ONESHOT;

  do
    {
      /* update fd-related kernel structures */
      fd_reify ();

      /* calculate blocking time */
      if (flags & EVLOOP_NONBLOCK)
        block = 0.;
      else
        {
          block = MAX_BLOCKTIME;

          if (rtimercnt)
            {
              ev_tstamp to = rtimers [0]->at - get_clock () + method_fudge;
              if (block > to) block = to;
            }

          if (atimercnt)
            {
              ev_tstamp to = atimers [0]->at - ev_time   () + method_fudge;
              if (block > to) block = to;
            }

          if (block < 0.) block = 0.;
        }

      method_poll (block);

      /* update ev_now, do magic */
      time_update ();

      /* put pending timers into pendign queue and reschedule them */
      /* absolute timers first */
      timers_reify (atimers, atimercnt, ev_now);
      /* relative timers second */
      timers_reify (rtimers, rtimercnt, now);

      call_pending ();
    }
  while (!ev_loop_done);
}

static void
wlist_add (struct ev_watcher_list **head, struct ev_watcher_list *elem)
{
  elem->next = *head;
  *head = elem;
}

static void
wlist_del (struct ev_watcher_list **head, struct ev_watcher_list *elem)
{
  while (*head)
    {
      if (*head == elem)
        {
          *head = elem->next;
          return;
        }

      head = &(*head)->next;
    }
}

static void
ev_start (struct ev_watcher *w, int active)
{
  w->pending = 0;
  w->active = active;
}

static void
ev_stop (struct ev_watcher *w)
{
  if (w->pending)
    pendings [w->pending - 1].w = 0;

  w->active = 0;
  /* nop */
}

void
evio_start (struct ev_io *w)
{
  if (ev_is_active (w))
    return;

  int fd = w->fd;

  ev_start ((struct ev_watcher *)w, 1);
  array_needsize (anfds, anfdmax, fd + 1, anfds_init);
  wlist_add ((struct ev_watcher_list **)&anfds[fd].head, (struct ev_watcher_list *)w);

  ++fdchangecnt;
  array_needsize (fdchanges, fdchangemax, fdchangecnt, );
  fdchanges [fdchangecnt - 1] = fd;
}

void
evio_stop (struct ev_io *w)
{
  if (!ev_is_active (w))
    return;

  wlist_del ((struct ev_watcher_list **)&anfds[w->fd].head, (struct ev_watcher_list *)w);
  ev_stop ((struct ev_watcher *)w);

  ++fdchangecnt;
  array_needsize (fdchanges, fdchangemax, fdchangecnt, );
  fdchanges [fdchangecnt - 1] = w->fd;
}

void
evtimer_start (struct ev_timer *w)
{
  if (ev_is_active (w))
    return;

  if (w->is_abs)
    {
      /* this formula differs from the one in timer_reify becuse we do not round up */
      if (w->repeat)
        w->at += ceil ((ev_now - w->at) / w->repeat) * w->repeat;

      ev_start ((struct ev_watcher *)w, ++atimercnt);
      array_needsize (atimers, atimermax, atimercnt, );
      atimers [atimercnt - 1] = w;
      upheap (atimers, atimercnt - 1);
    }
  else
    {
      w->at += now;

      ev_start ((struct ev_watcher *)w, ++rtimercnt);
      array_needsize (rtimers, rtimermax, rtimercnt, );
      rtimers [rtimercnt - 1] = w;
      upheap (rtimers, rtimercnt - 1);
    }

}

void
evtimer_stop (struct ev_timer *w)
{
  if (!ev_is_active (w))
    return;

  if (w->is_abs)
    {
      if (w->active < atimercnt--)
        {
          atimers [w->active - 1] = atimers [atimercnt];
          downheap (atimers, atimercnt, w->active - 1);
        }
    }
  else
    {
      if (w->active < rtimercnt--)
        {
          rtimers [w->active - 1] = rtimers [rtimercnt];
          downheap (rtimers, rtimercnt, w->active - 1);
        }
    }

  ev_stop ((struct ev_watcher *)w);
}

void
evsignal_start (struct ev_signal *w)
{
  if (ev_is_active (w))
    return;

  ev_start ((struct ev_watcher *)w, 1);
  array_needsize (signals, signalmax, w->signum, signals_init);
  wlist_add ((struct ev_watcher_list **)&signals [w->signum - 1].head, (struct ev_watcher_list *)w);

  if (!w->next)
    {
      struct sigaction sa;
      sa.sa_handler = sighandler;
      sigfillset (&sa.sa_mask);
      sa.sa_flags = 0;
      sigaction (w->signum, &sa, 0);
    }
}

void
evsignal_stop (struct ev_signal *w)
{
  if (!ev_is_active (w))
    return;

  wlist_del ((struct ev_watcher_list **)&signals [w->signum - 1].head, (struct ev_watcher_list *)w);
  ev_stop ((struct ev_watcher *)w);

  if (!signals [w->signum - 1].head)
    signal (w->signum, SIG_DFL);
}

/*****************************************************************************/
#if 1

static void
sin_cb (struct ev_io *w, int revents)
{
  fprintf (stderr, "sin %d, revents %d\n", w->fd, revents);
}

static void
ocb (struct ev_timer *w, int revents)
{
  //fprintf (stderr, "timer %f,%f (%x) (%f) d%p\n", w->at, w->repeat, revents, w->at - ev_time (), w->data);
  evtimer_stop (w);
  evtimer_start (w);
}

static void
scb (struct ev_signal *w, int revents)
{
  fprintf (stderr, "signal %x,%d\n", revents, w->signum);
}

int main (void)
{
  struct ev_io sin;

  ev_init (0);

  evw_init (&sin, sin_cb, 55);
  evio_set (&sin, 0, EV_READ);
  evio_start (&sin);

  struct ev_timer t[10000];

#if 0
  int i;
  for (i = 0; i < 10000; ++i)
    {
      struct ev_timer *w = t + i;
      evw_init (w, ocb, i);
      evtimer_set_abs (w, drand48 (), 0.99775533);
      evtimer_start (w);
      if (drand48 () < 0.5)
        evtimer_stop (w);
    }
#endif

  struct ev_timer t1;
  evw_init (&t1, ocb, 0);
  evtimer_set_abs (&t1, 5, 10);
  evtimer_start (&t1);

  struct ev_signal sig;
  evw_init (&sig, scb, 65535);
  evsignal_set (&sig, SIGQUIT);
  evsignal_start (&sig);

  ev_loop (0);

  return 0;
}

#endif


Revision:	1.7
Committed:	Wed Oct 31 00:24:16 2007 UTC (16 years, 6 months ago) by root
Content type:	text/plain
Branch:	MAIN
Changes since 1.6:	+109 -11 lines
Log Message:	signal support
#	Content
1	#include <math.h>
2	#include <stdlib.h>
3	#include <unistd.h>
4	#include <fcntl.h>
5	#include <signal.h>
6
7	#include <stdio.h>
8
9	#include <assert.h>
10	#include <errno.h>
11	#include <sys/time.h>
12	#include <time.h>
13
14	#ifdef CLOCK_MONOTONIC
15	# define HAVE_MONOTONIC 1
16	#endif
17
18	#define HAVE_REALTIME 1
19	#define HAVE_EPOLL 1
20	#define HAVE_SELECT 1
21
22	#define MIN_TIMEJUMP 1. /* minimum timejump that gets detected (if monotonic clock available) */
23	#define MAX_BLOCKTIME 60.
24
25	#include "ev.h"
26
27	struct ev_watcher {
28	EV_WATCHER (ev_watcher);
29	};
30
31	struct ev_watcher_list {
32	EV_WATCHER_LIST (ev_watcher_list);
33	};
34
35	static ev_tstamp now, diff; /* monotonic clock */
36	ev_tstamp ev_now;
37	int ev_method;
38
39	static int have_monotonic; /* runtime */
40
41	static ev_tstamp method_fudge; /* stupid epoll-returns-early bug */
42	static void (*method_modify)(int fd, int oev, int nev);
43	static void (*method_poll)(ev_tstamp timeout);
44
45	ev_tstamp
46	ev_time (void)
47	{
48	#if HAVE_REALTIME
49	struct timespec ts;
50	clock_gettime (CLOCK_REALTIME, &ts);
51	return ts.tv_sec + ts.tv_nsec * 1e-9;
52	#else
53	struct timeval tv;
54	gettimeofday (&tv, 0);
55	return tv.tv_sec + tv.tv_usec * 1e-6;
56	#endif
57	}
58
59	static ev_tstamp
60	get_clock (void)
61	{
62	#if HAVE_MONOTONIC
63	if (have_monotonic)
64	{
65	struct timespec ts;
66	clock_gettime (CLOCK_MONOTONIC, &ts);
67	return ts.tv_sec + ts.tv_nsec * 1e-9;
68	}
69	#endif
70
71	return ev_time ();
72	}
73
74	#define array_needsize(base,cur,cnt,init) \
75	if ((cnt) > cur) \
76	{ \
77	int newcnt = cur ? cur << 1 : 16; \
78	fprintf (stderr, "resize(" # base ") from %d to %d\n", cur, newcnt);\
79	base = realloc (base, sizeof (base) (newcnt)); \
80	init (base + cur, newcnt - cur); \
81	cur = newcnt; \
82	}
83
84	typedef struct
85	{
86	struct ev_io *head;
87	unsigned char wev, rev; /* want, received event set */
88	} ANFD;
89
90	static ANFD *anfds;
91	static int anfdmax;
92
93	static int *fdchanges;
94	static int fdchangemax, fdchangecnt;
95
96	static void
97	anfds_init (ANFD *base, int count)
98	{
99	while (count--)
100	{
101	base->head = 0;
102	base->wev = base->rev = EV_NONE;
103	++base;
104	}
105	}
106
107	typedef struct
108	{
109	struct ev_watcher *w;
110	int events;
111	} ANPENDING;
112
113	static ANPENDING *pendings;
114	static int pendingmax, pendingcnt;
115
116	static void
117	event (struct ev_watcher *w, int events)
118	{
119	w->pending = ++pendingcnt;
120	array_needsize (pendings, pendingmax, pendingcnt, );
121	pendings [pendingcnt - 1].w = w;
122	pendings [pendingcnt - 1].events = events;
123	}
124
125	static void
126	fd_event (int fd, int events)
127	{
128	ANFD *anfd = anfds + fd;
129	struct ev_io *w;
130
131	for (w = anfd->head; w; w = w->next)
132	{
133	int ev = w->events & events;
134
135	if (ev)
136	event ((struct ev_watcher *)w, ev);
137	}
138	}
139
140	static struct ev_timer **atimers;
141	static int atimermax, atimercnt;
142
143	static struct ev_timer **rtimers;
144	static int rtimermax, rtimercnt;
145
146	static void
147	upheap (struct ev_timer **timers, int k)
148	{
149	struct ev_timer *w = timers [k];
150
151	while (k && timers [k >> 1]->at > w->at)
152	{
153	timers [k] = timers [k >> 1];
154	timers [k]->active = k + 1;
155	k >>= 1;
156	}
157
158	timers [k] = w;
159	timers [k]->active = k + 1;
160
161	}
162
163	static void
164	downheap (struct ev_timer **timers, int N, int k)
165	{
166	struct ev_timer *w = timers [k];
167
168	while (k < (N >> 1))
169	{
170	int j = k << 1;
171
172	if (j + 1 < N && timers [j]->at > timers [j + 1]->at)
173	++j;
174
175	if (w->at <= timers [j]->at)
176	break;
177
178	timers [k] = timers [j];
179	timers [k]->active = k + 1;
180	k = j;
181	}
182
183	timers [k] = w;
184	timers [k]->active = k + 1;
185	}
186
187	typedef struct
188	{
189	struct ev_signal *head;
190	sig_atomic_t gotsig;
191	} ANSIG;
192
193	static ANSIG *signals;
194	static int signalmax;
195
196	static int sigpipe [2];
197	static sig_atomic_t gotsig;
198	static struct ev_io sigev;
199
200	static void
201	signals_init (ANSIG *base, int count)
202	{
203	while (count--)
204	{
205	base->head = 0;
206	base->gotsig = 0;
207	++base;
208	}
209	}
210
211	static void
212	sighandler (int signum)
213	{
214	signals [signum - 1].gotsig = 1;
215
216	if (!gotsig)
217	{
218	gotsig = 1;
219	write (sigpipe [1], &gotsig, 1);
220	}
221	}
222
223	static void
224	sigcb (struct ev_io *iow, int revents)
225	{
226	struct ev_signal *w;
227	int sig;
228
229	gotsig = 0;
230	read (sigpipe [0], &revents, 1);
231
232	for (sig = signalmax; sig--; )
233	if (signals [sig].gotsig)
234	{
235	signals [sig].gotsig = 0;
236
237	for (w = signals [sig].head; w; w = w->next)
238	event ((struct ev_watcher *)w, EV_SIGNAL);
239	}
240	}
241
242	static void
243	siginit (void)
244	{
245	fcntl (sigpipe [0], F_SETFD, FD_CLOEXEC);
246	fcntl (sigpipe [1], F_SETFD, FD_CLOEXEC);
247
248	/* rather than sort out wether we really need nb, set it */
249	fcntl (sigpipe [0], F_SETFL, O_NONBLOCK);
250	fcntl (sigpipe [1], F_SETFL, O_NONBLOCK);
251
252	evio_set (&sigev, sigpipe [0], EV_READ);
253	evio_start (&sigev);
254	}
255
256	#if HAVE_EPOLL
257	# include "ev_epoll.c"
258	#endif
259	#if HAVE_SELECT
260	# include "ev_select.c"
261	#endif
262
263	int ev_init (int flags)
264	{
265	#if HAVE_MONOTONIC
266	{
267	struct timespec ts;
268	if (!clock_gettime (CLOCK_MONOTONIC, &ts))
269	have_monotonic = 1;
270	}
271	#endif
272
273	ev_now = ev_time ();
274	now = get_clock ();
275	diff = ev_now - now;
276
277	if (pipe (sigpipe))
278	return 0;
279
280	ev_method = EVMETHOD_NONE;
281	#if HAVE_EPOLL
282	if (ev_method == EVMETHOD_NONE) epoll_init (flags);
283	#endif
284	#if HAVE_SELECT
285	if (ev_method == EVMETHOD_NONE) select_init (flags);
286	#endif
287
288	if (ev_method)
289	{
290	evw_init (&sigev, sigcb, 0);
291	siginit ();
292	}
293
294	return ev_method;
295	}
296
297	void ev_prefork (void)
298	{
299	}
300
301	void ev_postfork_parent (void)
302	{
303	}
304
305	void ev_postfork_child (void)
306	{
307	#if HAVE_EPOLL
308	if (ev_method == EVMETHOD_EPOLL)
309	epoll_postfork_child ();
310	#endif
311
312	evio_stop (&sigev);
313	close (sigpipe [0]);
314	close (sigpipe [1]);
315	pipe (sigpipe);
316	siginit ();
317	}
318
319	static void
320	fd_reify (void)
321	{
322	int i;
323
324	for (i = 0; i < fdchangecnt; ++i)
325	{
326	int fd = fdchanges [i];
327	ANFD *anfd = anfds + fd;
328	struct ev_io *w;
329
330	int wev = 0;
331
332	for (w = anfd->head; w; w = w->next)
333	wev \|= w->events;
334
335	if (anfd->wev != wev)
336	{
337	method_modify (fd, anfd->wev, wev);
338	anfd->wev = wev;
339	}
340	}
341
342	fdchangecnt = 0;
343	}
344
345	static void
346	call_pending ()
347	{
348	int i;
349
350	for (i = 0; i < pendingcnt; ++i)
351	{
352	ANPENDING *p = pendings + i;
353
354	if (p->w)
355	{
356	p->w->pending = 0;
357	p->w->cb (p->w, p->events);
358	}
359	}
360
361	pendingcnt = 0;
362	}
363
364	static void
365	timers_reify (struct ev_timer **timers, int timercnt, ev_tstamp now)
366	{
367	while (timercnt && timers [0]->at <= now)
368	{
369	struct ev_timer *w = timers [0];
370
371	/* first reschedule or stop timer */
372	if (w->repeat)
373	{
374	if (w->is_abs)
375	w->at += floor ((now - w->at) / w->repeat + 1.) * w->repeat;
376	else
377	w->at = now + w->repeat;
378
379	assert (w->at > now);
380
381	downheap (timers, timercnt, 0);
382	}
383	else
384	{
385	evtimer_stop (w); /* nonrepeating: stop timer */
386	--timercnt; /* maybe pass by reference instead? */
387	}
388
389	event ((struct ev_watcher *)w, EV_TIMEOUT);
390	}
391	}
392
393	static void
394	time_update ()
395	{
396	int i;
397	ev_now = ev_time ();
398
399	if (have_monotonic)
400	{
401	ev_tstamp odiff = diff;
402
403	/* detecting time jumps is much more difficult */
404	for (i = 2; --i; ) /* loop a few times, before making important decisions */
405	{
406	now = get_clock ();
407	diff = ev_now - now;
408
409	if (fabs (odiff - diff) < MIN_TIMEJUMP)
410	return; /* all is well */
411
412	ev_now = ev_time ();
413	}
414
415	/* time jump detected, reschedule atimers */
416	for (i = 0; i < atimercnt; ++i)
417	{
418	struct ev_timer *w = atimers [i];
419	w->at += ceil ((ev_now - w->at) / w->repeat + 1.) * w->repeat;
420	}
421	}
422	else
423	{
424	if (now > ev_now \|\| now < ev_now - MAX_BLOCKTIME - MIN_TIMEJUMP)
425	/* time jump detected, adjust rtimers */
426	for (i = 0; i < rtimercnt; ++i)
427	rtimers [i]->at += ev_now - now;
428
429	now = ev_now;
430	}
431	}
432
433	int ev_loop_done;
434
435	void ev_loop (int flags)
436	{
437	double block;
438	ev_loop_done = flags & EVLOOP_ONESHOT;
439
440	do
441	{
442	/* update fd-related kernel structures */
443	fd_reify ();
444
445	/* calculate blocking time */
446	if (flags & EVLOOP_NONBLOCK)
447	block = 0.;
448	else
449	{
450	block = MAX_BLOCKTIME;
451
452	if (rtimercnt)
453	{
454	ev_tstamp to = rtimers [0]->at - get_clock () + method_fudge;
455	if (block > to) block = to;
456	}
457
458	if (atimercnt)
459	{
460	ev_tstamp to = atimers [0]->at - ev_time () + method_fudge;
461	if (block > to) block = to;
462	}
463
464	if (block < 0.) block = 0.;
465	}
466
467	method_poll (block);
468
469	/* update ev_now, do magic */
470	time_update ();
471
472	/* put pending timers into pendign queue and reschedule them */
473	/* absolute timers first */
474	timers_reify (atimers, atimercnt, ev_now);
475	/* relative timers second */
476	timers_reify (rtimers, rtimercnt, now);
477
478	call_pending ();
479	}
480	while (!ev_loop_done);
481	}
482
483	static void
484	wlist_add (struct ev_watcher_list *head, struct ev_watcher_list elem)
485	{
486	elem->next = *head;
487	*head = elem;
488	}
489
490	static void
491	wlist_del (struct ev_watcher_list *head, struct ev_watcher_list elem)
492	{
493	while (*head)
494	{
495	if (*head == elem)
496	{
497	*head = elem->next;
498	return;
499	}
500
501	head = &(*head)->next;
502	}
503	}
504
505	static void
506	ev_start (struct ev_watcher *w, int active)
507	{
508	w->pending = 0;
509	w->active = active;
510	}
511
512	static void
513	ev_stop (struct ev_watcher *w)
514	{
515	if (w->pending)
516	pendings [w->pending - 1].w = 0;
517
518	w->active = 0;
519	/* nop */
520	}
521
522	void
523	evio_start (struct ev_io *w)
524	{
525	if (ev_is_active (w))
526	return;
527
528	int fd = w->fd;
529
530	ev_start ((struct ev_watcher *)w, 1);
531	array_needsize (anfds, anfdmax, fd + 1, anfds_init);
532	wlist_add ((struct ev_watcher_list *)&anfds[fd].head, (struct ev_watcher_list )w);
533
534	++fdchangecnt;
535	array_needsize (fdchanges, fdchangemax, fdchangecnt, );
536	fdchanges [fdchangecnt - 1] = fd;
537	}
538
539	void
540	evio_stop (struct ev_io *w)
541	{
542	if (!ev_is_active (w))
543	return;
544
545	wlist_del ((struct ev_watcher_list *)&anfds[w->fd].head, (struct ev_watcher_list )w);
546	ev_stop ((struct ev_watcher *)w);
547
548	++fdchangecnt;
549	array_needsize (fdchanges, fdchangemax, fdchangecnt, );
550	fdchanges [fdchangecnt - 1] = w->fd;
551	}
552
553	void
554	evtimer_start (struct ev_timer *w)
555	{
556	if (ev_is_active (w))
557	return;
558
559	if (w->is_abs)
560	{
561	/* this formula differs from the one in timer_reify becuse we do not round up */
562	if (w->repeat)
563	w->at += ceil ((ev_now - w->at) / w->repeat) * w->repeat;
564
565	ev_start ((struct ev_watcher *)w, ++atimercnt);
566	array_needsize (atimers, atimermax, atimercnt, );
567	atimers [atimercnt - 1] = w;
568	upheap (atimers, atimercnt - 1);
569	}
570	else
571	{
572	w->at += now;
573
574	ev_start ((struct ev_watcher *)w, ++rtimercnt);
575	array_needsize (rtimers, rtimermax, rtimercnt, );
576	rtimers [rtimercnt - 1] = w;
577	upheap (rtimers, rtimercnt - 1);
578	}
579
580	}
581
582	void
583	evtimer_stop (struct ev_timer *w)
584	{
585	if (!ev_is_active (w))
586	return;
587
588	if (w->is_abs)
589	{
590	if (w->active < atimercnt--)
591	{
592	atimers [w->active - 1] = atimers [atimercnt];
593	downheap (atimers, atimercnt, w->active - 1);
594	}
595	}
596	else
597	{
598	if (w->active < rtimercnt--)
599	{
600	rtimers [w->active - 1] = rtimers [rtimercnt];
601	downheap (rtimers, rtimercnt, w->active - 1);
602	}
603	}
604
605	ev_stop ((struct ev_watcher *)w);
606	}
607
608	void
609	evsignal_start (struct ev_signal *w)
610	{
611	if (ev_is_active (w))
612	return;
613
614	ev_start ((struct ev_watcher *)w, 1);
615	array_needsize (signals, signalmax, w->signum, signals_init);
616	wlist_add ((struct ev_watcher_list *)&signals [w->signum - 1].head, (struct ev_watcher_list )w);
617
618	if (!w->next)
619	{
620	struct sigaction sa;
621	sa.sa_handler = sighandler;
622	sigfillset (&sa.sa_mask);
623	sa.sa_flags = 0;
624	sigaction (w->signum, &sa, 0);
625	}
626	}
627
628	void
629	evsignal_stop (struct ev_signal *w)
630	{
631	if (!ev_is_active (w))
632	return;
633
634	wlist_del ((struct ev_watcher_list *)&signals [w->signum - 1].head, (struct ev_watcher_list )w);
635	ev_stop ((struct ev_watcher *)w);
636
637	if (!signals [w->signum - 1].head)
638	signal (w->signum, SIG_DFL);
639	}
640
641	/*****************************************************************************/
642	#if 1
643
644	static void
645	sin_cb (struct ev_io *w, int revents)
646	{
647	fprintf (stderr, "sin %d, revents %d\n", w->fd, revents);
648	}
649
650	static void
651	ocb (struct ev_timer *w, int revents)
652	{
653	//fprintf (stderr, "timer %f,%f (%x) (%f) d%p\n", w->at, w->repeat, revents, w->at - ev_time (), w->data);
654	evtimer_stop (w);
655	evtimer_start (w);
656	}
657
658	static void
659	scb (struct ev_signal *w, int revents)
660	{
661	fprintf (stderr, "signal %x,%d\n", revents, w->signum);
662	}
663
664	int main (void)
665	{
666	struct ev_io sin;
667
668	ev_init (0);
669
670	evw_init (&sin, sin_cb, 55);
671	evio_set (&sin, 0, EV_READ);
672	evio_start (&sin);
673
674	struct ev_timer t[10000];
675
676	#if 0
677	int i;
678	for (i = 0; i < 10000; ++i)
679	{
680	struct ev_timer *w = t + i;
681	evw_init (w, ocb, i);
682	evtimer_set_abs (w, drand48 (), 0.99775533);
683	evtimer_start (w);
684	if (drand48 () < 0.5)
685	evtimer_stop (w);
686	}
687	#endif
688
689	struct ev_timer t1;
690	evw_init (&t1, ocb, 0);
691	evtimer_set_abs (&t1, 5, 10);
692	evtimer_start (&t1);
693
694	struct ev_signal sig;
695	evw_init (&sig, scb, 65535);
696	evsignal_set (&sig, SIGQUIT);
697	evsignal_start (&sig);
698
699	ev_loop (0);
700
701	return 0;
702	}
703
704	#endif
705
706
707
708