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
#	User	Rev	Content
1	root	1.1	#include <math.h>
2			#include <stdlib.h>
3	root	1.7	#include <unistd.h>
4			#include <fcntl.h>
5			#include <signal.h>
6	root	1.1
7			#include <stdio.h>
8
9	root	1.4	#include <assert.h>
10	root	1.1	#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	root	1.6	#define HAVE_REALTIME 1
19	root	1.1	#define HAVE_EPOLL 1
20	root	1.5	#define HAVE_SELECT 1
21	root	1.1
22	root	1.4	#define MIN_TIMEJUMP 1. /* minimum timejump that gets detected (if monotonic clock available) */
23	root	1.1	#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	root	1.4	static ev_tstamp now, diff; /* monotonic clock */
36	root	1.1	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	root	1.5	static void (*method_modify)(int fd, int oev, int nev);
43	root	1.1	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	root	1.2	int newcnt = cur ? cur << 1 : 16; \
78	root	1.1	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	root	1.4	static struct ev_timer **atimers;
141			static int atimermax, atimercnt;
142
143			static struct ev_timer **rtimers;
144			static int rtimermax, rtimercnt;
145	root	1.1
146			static void
147	root	1.4	upheap (struct ev_timer **timers, int k)
148	root	1.1	{
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	root	1.4	downheap (struct ev_timer **timers, int N, int k)
165	root	1.1	{
166			struct ev_timer *w = timers [k];
167
168	root	1.4	while (k < (N >> 1))
169	root	1.1	{
170			int j = k << 1;
171
172	root	1.4	if (j + 1 < N && timers [j]->at > timers [j + 1]->at)
173	root	1.1	++j;
174
175			if (w->at <= timers [j]->at)
176			break;
177
178			timers [k] = timers [j];
179	root	1.2	timers [k]->active = k + 1;
180	root	1.1	k = j;
181			}
182
183			timers [k] = w;
184			timers [k]->active = k + 1;
185			}
186
187	root	1.7	typedef struct
188			{
189			struct ev_signal *head;
190			sig_atomic_t gotsig;
191			} ANSIG;
192
193			static ANSIG *signals;
194	root	1.4	static int signalmax;
195	root	1.1
196	root	1.7	static int sigpipe [2];
197			static sig_atomic_t gotsig;
198			static struct ev_io sigev;
199
200	root	1.1	static void
201	root	1.7	signals_init (ANSIG *base, int count)
202	root	1.1	{
203			while (count--)
204	root	1.7	{
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	root	1.1	}
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	root	1.4	now = get_clock ();
275			diff = ev_now - now;
276	root	1.1
277	root	1.7	if (pipe (sigpipe))
278			return 0;
279
280			ev_method = EVMETHOD_NONE;
281	root	1.1	#if HAVE_EPOLL
282	root	1.7	if (ev_method == EVMETHOD_NONE) epoll_init (flags);
283	root	1.1	#endif
284			#if HAVE_SELECT
285	root	1.7	if (ev_method == EVMETHOD_NONE) select_init (flags);
286	root	1.1	#endif
287
288	root	1.7	if (ev_method)
289			{
290			evw_init (&sigev, sigcb, 0);
291			siginit ();
292			}
293
294	root	1.1	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	root	1.5	if (ev_method == EVMETHOD_EPOLL)
309			epoll_postfork_child ();
310	root	1.1	#endif
311	root	1.7
312			evio_stop (&sigev);
313			close (sigpipe [0]);
314			close (sigpipe [1]);
315			pipe (sigpipe);
316			siginit ();
317	root	1.1	}
318
319			static void
320	root	1.5	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	root	1.1	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	root	1.4	timers_reify (struct ev_timer **timers, int timercnt, ev_tstamp now)
366	root	1.1	{
367	root	1.4	while (timercnt && timers [0]->at <= now)
368	root	1.1	{
369			struct ev_timer *w = timers [0];
370
371	root	1.4	/* first reschedule or stop timer */
372	root	1.1	if (w->repeat)
373			{
374			if (w->is_abs)
375	root	1.4	w->at += floor ((now - w->at) / w->repeat + 1.) * w->repeat;
376	root	1.1	else
377	root	1.4	w->at = now + w->repeat;
378
379			assert (w->at > now);
380	root	1.1
381	root	1.4	downheap (timers, timercnt, 0);
382	root	1.1	}
383			else
384	root	1.4	{
385			evtimer_stop (w); /* nonrepeating: stop timer */
386			--timercnt; /* maybe pass by reference instead? */
387			}
388	root	1.1
389			event ((struct ev_watcher *)w, EV_TIMEOUT);
390			}
391			}
392
393	root	1.4	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	root	1.1	int ev_loop_done;
434
435	root	1.4	void ev_loop (int flags)
436	root	1.1	{
437			double block;
438			ev_loop_done = flags & EVLOOP_ONESHOT;
439
440			do
441			{
442			/* update fd-related kernel structures */
443	root	1.5	fd_reify ();
444	root	1.1
445			/* calculate blocking time */
446			if (flags & EVLOOP_NONBLOCK)
447			block = 0.;
448			else
449			{
450	root	1.4	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	root	1.1	if (block < 0.) block = 0.;
465			}
466
467			method_poll (block);
468
469	root	1.4	/* update ev_now, do magic */
470			time_update ();
471
472	root	1.1	/* put pending timers into pendign queue and reschedule them */
473	root	1.4	/* absolute timers first */
474			timers_reify (atimers, atimercnt, ev_now);
475			/* relative timers second */
476			timers_reify (rtimers, rtimercnt, now);
477	root	1.1
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	root	1.2	/* this formula differs from the one in timer_reify becuse we do not round up */
562	root	1.1	if (w->repeat)
563			w->at += ceil ((ev_now - w->at) / w->repeat) * w->repeat;
564	root	1.4
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	root	1.1	}
570			else
571	root	1.4	{
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	root	1.1
580			}
581
582			void
583			evtimer_stop (struct ev_timer *w)
584			{
585			if (!ev_is_active (w))
586			return;
587
588	root	1.4	if (w->is_abs)
589	root	1.2	{
590	root	1.4	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	root	1.2	}
604
605	root	1.1	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	root	1.7	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	root	1.1	}
627
628			void
629			evsignal_stop (struct ev_signal *w)
630			{
631			if (!ev_is_active (w))
632			return;
633
634	root	1.7	wlist_del ((struct ev_watcher_list *)&signals [w->signum - 1].head, (struct ev_watcher_list )w);
635	root	1.1	ev_stop ((struct ev_watcher *)w);
636	root	1.7
637			if (!signals [w->signum - 1].head)
638			signal (w->signum, SIG_DFL);
639	root	1.1	}
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	root	1.4	//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	root	1.1	}
657
658	root	1.7	static void
659			scb (struct ev_signal *w, int revents)
660			{
661			fprintf (stderr, "signal %x,%d\n", revents, w->signum);
662			}
663
664	root	1.1	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	root	1.4	struct ev_timer t[10000];
675	root	1.2
676	root	1.7	#if 0
677	root	1.2	int i;
678	root	1.4	for (i = 0; i < 10000; ++i)
679	root	1.2	{
680			struct ev_timer *w = t + i;
681			evw_init (w, ocb, i);
682	root	1.4	evtimer_set_abs (w, drand48 (), 0.99775533);
683	root	1.2	evtimer_start (w);
684			if (drand48 () < 0.5)
685			evtimer_stop (w);
686			}
687	root	1.4	#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	root	1.1
694	root	1.7	struct ev_signal sig;
695			evw_init (&sig, scb, 65535);
696			evsignal_set (&sig, SIGQUIT);
697			evsignal_start (&sig);
698
699	root	1.1	ev_loop (0);
700
701			return 0;
702			}
703
704			#endif
705
706
707
708