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 ev_hook hooks [EVHOOK_NUM];

void
ev_hook_register (int type, ev_hook hook)
{
  hooks [type] = hook;
}

void
ev_hook_unregister (int type, ev_hook hook)
{
  hooks [type] = 0;
}

static void
hook_call (int type)
{
  if (hooks [type])
    hooks [type] ();
}

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
    {
      hook_call (EVHOOK_PREPOLL);

      /* 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 ();

      hook_call (EVHOOK_POSTPOLL);

      /* 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 1
  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:	1.8
Committed:	Wed Oct 31 00:32:33 2007 UTC (16 years, 7 months ago) by root
Content type:	text/plain
Branch:	MAIN
Changes since 1.7:	+44 -1 lines
Log Message:	implement primitive hook management
#	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	root	1.8	/*****************************************************************************/
46
47	root	1.1	ev_tstamp
48			ev_time (void)
49			{
50			#if HAVE_REALTIME
51			struct timespec ts;
52			clock_gettime (CLOCK_REALTIME, &ts);
53			return ts.tv_sec + ts.tv_nsec * 1e-9;
54			#else
55			struct timeval tv;
56			gettimeofday (&tv, 0);
57			return tv.tv_sec + tv.tv_usec * 1e-6;
58			#endif
59			}
60
61			static ev_tstamp
62			get_clock (void)
63			{
64			#if HAVE_MONOTONIC
65			if (have_monotonic)
66			{
67			struct timespec ts;
68			clock_gettime (CLOCK_MONOTONIC, &ts);
69			return ts.tv_sec + ts.tv_nsec * 1e-9;
70			}
71			#endif
72
73			return ev_time ();
74			}
75
76			#define array_needsize(base,cur,cnt,init) \
77			if ((cnt) > cur) \
78			{ \
79	root	1.2	int newcnt = cur ? cur << 1 : 16; \
80	root	1.1	fprintf (stderr, "resize(" # base ") from %d to %d\n", cur, newcnt);\
81			base = realloc (base, sizeof (base) (newcnt)); \
82			init (base + cur, newcnt - cur); \
83			cur = newcnt; \
84			}
85
86	root	1.8	/*****************************************************************************/
87
88	root	1.1	typedef struct
89			{
90			struct ev_io *head;
91			unsigned char wev, rev; /* want, received event set */
92			} ANFD;
93
94			static ANFD *anfds;
95			static int anfdmax;
96
97			static int *fdchanges;
98			static int fdchangemax, fdchangecnt;
99
100			static void
101			anfds_init (ANFD *base, int count)
102			{
103			while (count--)
104			{
105			base->head = 0;
106			base->wev = base->rev = EV_NONE;
107			++base;
108			}
109			}
110
111			typedef struct
112			{
113			struct ev_watcher *w;
114			int events;
115			} ANPENDING;
116
117			static ANPENDING *pendings;
118			static int pendingmax, pendingcnt;
119
120			static void
121			event (struct ev_watcher *w, int events)
122			{
123			w->pending = ++pendingcnt;
124			array_needsize (pendings, pendingmax, pendingcnt, );
125			pendings [pendingcnt - 1].w = w;
126			pendings [pendingcnt - 1].events = events;
127			}
128
129			static void
130			fd_event (int fd, int events)
131			{
132			ANFD *anfd = anfds + fd;
133			struct ev_io *w;
134
135			for (w = anfd->head; w; w = w->next)
136			{
137			int ev = w->events & events;
138
139			if (ev)
140			event ((struct ev_watcher *)w, ev);
141			}
142			}
143
144	root	1.8	/*****************************************************************************/
145
146	root	1.4	static struct ev_timer **atimers;
147			static int atimermax, atimercnt;
148
149			static struct ev_timer **rtimers;
150			static int rtimermax, rtimercnt;
151	root	1.1
152			static void
153	root	1.4	upheap (struct ev_timer **timers, int k)
154	root	1.1	{
155			struct ev_timer *w = timers [k];
156
157			while (k && timers [k >> 1]->at > w->at)
158			{
159			timers [k] = timers [k >> 1];
160			timers [k]->active = k + 1;
161			k >>= 1;
162			}
163
164			timers [k] = w;
165			timers [k]->active = k + 1;
166
167			}
168
169			static void
170	root	1.4	downheap (struct ev_timer **timers, int N, int k)
171	root	1.1	{
172			struct ev_timer *w = timers [k];
173
174	root	1.4	while (k < (N >> 1))
175	root	1.1	{
176			int j = k << 1;
177
178	root	1.4	if (j + 1 < N && timers [j]->at > timers [j + 1]->at)
179	root	1.1	++j;
180
181			if (w->at <= timers [j]->at)
182			break;
183
184			timers [k] = timers [j];
185	root	1.2	timers [k]->active = k + 1;
186	root	1.1	k = j;
187			}
188
189			timers [k] = w;
190			timers [k]->active = k + 1;
191			}
192
193	root	1.8	/*****************************************************************************/
194
195	root	1.7	typedef struct
196			{
197			struct ev_signal *head;
198			sig_atomic_t gotsig;
199			} ANSIG;
200
201			static ANSIG *signals;
202	root	1.4	static int signalmax;
203	root	1.1
204	root	1.7	static int sigpipe [2];
205			static sig_atomic_t gotsig;
206			static struct ev_io sigev;
207
208	root	1.1	static void
209	root	1.7	signals_init (ANSIG *base, int count)
210	root	1.1	{
211			while (count--)
212	root	1.7	{
213			base->head = 0;
214			base->gotsig = 0;
215			++base;
216			}
217			}
218
219			static void
220			sighandler (int signum)
221			{
222			signals [signum - 1].gotsig = 1;
223
224			if (!gotsig)
225			{
226			gotsig = 1;
227			write (sigpipe [1], &gotsig, 1);
228			}
229			}
230
231			static void
232			sigcb (struct ev_io *iow, int revents)
233			{
234			struct ev_signal *w;
235			int sig;
236
237			gotsig = 0;
238			read (sigpipe [0], &revents, 1);
239
240			for (sig = signalmax; sig--; )
241			if (signals [sig].gotsig)
242			{
243			signals [sig].gotsig = 0;
244
245			for (w = signals [sig].head; w; w = w->next)
246			event ((struct ev_watcher *)w, EV_SIGNAL);
247			}
248			}
249
250			static void
251			siginit (void)
252			{
253			fcntl (sigpipe [0], F_SETFD, FD_CLOEXEC);
254			fcntl (sigpipe [1], F_SETFD, FD_CLOEXEC);
255
256			/* rather than sort out wether we really need nb, set it */
257			fcntl (sigpipe [0], F_SETFL, O_NONBLOCK);
258			fcntl (sigpipe [1], F_SETFL, O_NONBLOCK);
259
260			evio_set (&sigev, sigpipe [0], EV_READ);
261			evio_start (&sigev);
262	root	1.1	}
263
264	root	1.8	/*****************************************************************************/
265
266	root	1.1	#if HAVE_EPOLL
267			# include "ev_epoll.c"
268			#endif
269			#if HAVE_SELECT
270			# include "ev_select.c"
271			#endif
272
273			int ev_init (int flags)
274			{
275			#if HAVE_MONOTONIC
276			{
277			struct timespec ts;
278			if (!clock_gettime (CLOCK_MONOTONIC, &ts))
279			have_monotonic = 1;
280			}
281			#endif
282
283			ev_now = ev_time ();
284	root	1.4	now = get_clock ();
285			diff = ev_now - now;
286	root	1.1
287	root	1.7	if (pipe (sigpipe))
288			return 0;
289
290			ev_method = EVMETHOD_NONE;
291	root	1.1	#if HAVE_EPOLL
292	root	1.7	if (ev_method == EVMETHOD_NONE) epoll_init (flags);
293	root	1.1	#endif
294			#if HAVE_SELECT
295	root	1.7	if (ev_method == EVMETHOD_NONE) select_init (flags);
296	root	1.1	#endif
297
298	root	1.7	if (ev_method)
299			{
300			evw_init (&sigev, sigcb, 0);
301			siginit ();
302			}
303
304	root	1.1	return ev_method;
305			}
306
307	root	1.8	/*****************************************************************************/
308
309	root	1.1	void ev_prefork (void)
310			{
311			}
312
313			void ev_postfork_parent (void)
314			{
315			}
316
317			void ev_postfork_child (void)
318			{
319			#if HAVE_EPOLL
320	root	1.5	if (ev_method == EVMETHOD_EPOLL)
321			epoll_postfork_child ();
322	root	1.1	#endif
323	root	1.7
324			evio_stop (&sigev);
325			close (sigpipe [0]);
326			close (sigpipe [1]);
327			pipe (sigpipe);
328			siginit ();
329	root	1.1	}
330
331	root	1.8	/*****************************************************************************/
332
333			static ev_hook hooks [EVHOOK_NUM];
334
335			void
336			ev_hook_register (int type, ev_hook hook)
337			{
338			hooks [type] = hook;
339			}
340
341			void
342			ev_hook_unregister (int type, ev_hook hook)
343			{
344			hooks [type] = 0;
345			}
346
347			static void
348			hook_call (int type)
349			{
350			if (hooks [type])
351			hooks [type] ();
352			}
353
354	root	1.1	static void
355	root	1.5	fd_reify (void)
356			{
357			int i;
358
359			for (i = 0; i < fdchangecnt; ++i)
360			{
361			int fd = fdchanges [i];
362			ANFD *anfd = anfds + fd;
363			struct ev_io *w;
364
365			int wev = 0;
366
367			for (w = anfd->head; w; w = w->next)
368			wev \|= w->events;
369
370			if (anfd->wev != wev)
371			{
372			method_modify (fd, anfd->wev, wev);
373			anfd->wev = wev;
374			}
375			}
376
377			fdchangecnt = 0;
378			}
379
380			static void
381	root	1.1	call_pending ()
382			{
383			int i;
384
385			for (i = 0; i < pendingcnt; ++i)
386			{
387			ANPENDING *p = pendings + i;
388
389			if (p->w)
390			{
391			p->w->pending = 0;
392			p->w->cb (p->w, p->events);
393			}
394			}
395
396			pendingcnt = 0;
397			}
398
399			static void
400	root	1.4	timers_reify (struct ev_timer **timers, int timercnt, ev_tstamp now)
401	root	1.1	{
402	root	1.4	while (timercnt && timers [0]->at <= now)
403	root	1.1	{
404			struct ev_timer *w = timers [0];
405
406	root	1.4	/* first reschedule or stop timer */
407	root	1.1	if (w->repeat)
408			{
409			if (w->is_abs)
410	root	1.4	w->at += floor ((now - w->at) / w->repeat + 1.) * w->repeat;
411	root	1.1	else
412	root	1.4	w->at = now + w->repeat;
413
414			assert (w->at > now);
415	root	1.1
416	root	1.4	downheap (timers, timercnt, 0);
417	root	1.1	}
418			else
419	root	1.4	{
420			evtimer_stop (w); /* nonrepeating: stop timer */
421			--timercnt; /* maybe pass by reference instead? */
422			}
423	root	1.1
424			event ((struct ev_watcher *)w, EV_TIMEOUT);
425			}
426			}
427
428	root	1.4	static void
429			time_update ()
430			{
431			int i;
432			ev_now = ev_time ();
433
434			if (have_monotonic)
435			{
436			ev_tstamp odiff = diff;
437
438			/* detecting time jumps is much more difficult */
439			for (i = 2; --i; ) /* loop a few times, before making important decisions */
440			{
441			now = get_clock ();
442			diff = ev_now - now;
443
444			if (fabs (odiff - diff) < MIN_TIMEJUMP)
445			return; /* all is well */
446
447			ev_now = ev_time ();
448			}
449
450			/* time jump detected, reschedule atimers */
451			for (i = 0; i < atimercnt; ++i)
452			{
453			struct ev_timer *w = atimers [i];
454			w->at += ceil ((ev_now - w->at) / w->repeat + 1.) * w->repeat;
455			}
456			}
457			else
458			{
459			if (now > ev_now \|\| now < ev_now - MAX_BLOCKTIME - MIN_TIMEJUMP)
460			/* time jump detected, adjust rtimers */
461			for (i = 0; i < rtimercnt; ++i)
462			rtimers [i]->at += ev_now - now;
463
464			now = ev_now;
465			}
466			}
467
468	root	1.1	int ev_loop_done;
469
470	root	1.4	void ev_loop (int flags)
471	root	1.1	{
472			double block;
473			ev_loop_done = flags & EVLOOP_ONESHOT;
474
475			do
476			{
477	root	1.8	hook_call (EVHOOK_PREPOLL);
478
479	root	1.1	/* update fd-related kernel structures */
480	root	1.5	fd_reify ();
481	root	1.1
482			/* calculate blocking time */
483			if (flags & EVLOOP_NONBLOCK)
484			block = 0.;
485			else
486			{
487	root	1.4	block = MAX_BLOCKTIME;
488
489			if (rtimercnt)
490			{
491			ev_tstamp to = rtimers [0]->at - get_clock () + method_fudge;
492			if (block > to) block = to;
493			}
494
495			if (atimercnt)
496			{
497			ev_tstamp to = atimers [0]->at - ev_time () + method_fudge;
498			if (block > to) block = to;
499			}
500
501	root	1.1	if (block < 0.) block = 0.;
502			}
503
504			method_poll (block);
505
506	root	1.4	/* update ev_now, do magic */
507			time_update ();
508
509	root	1.8	hook_call (EVHOOK_POSTPOLL);
510
511	root	1.1	/* put pending timers into pendign queue and reschedule them */
512	root	1.4	/* absolute timers first */
513			timers_reify (atimers, atimercnt, ev_now);
514			/* relative timers second */
515			timers_reify (rtimers, rtimercnt, now);
516	root	1.1
517			call_pending ();
518			}
519			while (!ev_loop_done);
520			}
521
522	root	1.8	/*****************************************************************************/
523
524	root	1.1	static void
525			wlist_add (struct ev_watcher_list *head, struct ev_watcher_list elem)
526			{
527			elem->next = *head;
528			*head = elem;
529			}
530
531			static void
532			wlist_del (struct ev_watcher_list *head, struct ev_watcher_list elem)
533			{
534			while (*head)
535			{
536			if (*head == elem)
537			{
538			*head = elem->next;
539			return;
540			}
541
542			head = &(*head)->next;
543			}
544			}
545
546			static void
547			ev_start (struct ev_watcher *w, int active)
548			{
549			w->pending = 0;
550			w->active = active;
551			}
552
553			static void
554			ev_stop (struct ev_watcher *w)
555			{
556			if (w->pending)
557			pendings [w->pending - 1].w = 0;
558
559			w->active = 0;
560			/* nop */
561			}
562
563	root	1.8	/*****************************************************************************/
564
565	root	1.1	void
566			evio_start (struct ev_io *w)
567			{
568			if (ev_is_active (w))
569			return;
570
571			int fd = w->fd;
572
573			ev_start ((struct ev_watcher *)w, 1);
574			array_needsize (anfds, anfdmax, fd + 1, anfds_init);
575			wlist_add ((struct ev_watcher_list *)&anfds[fd].head, (struct ev_watcher_list )w);
576
577			++fdchangecnt;
578			array_needsize (fdchanges, fdchangemax, fdchangecnt, );
579			fdchanges [fdchangecnt - 1] = fd;
580			}
581
582			void
583			evio_stop (struct ev_io *w)
584			{
585			if (!ev_is_active (w))
586			return;
587
588			wlist_del ((struct ev_watcher_list *)&anfds[w->fd].head, (struct ev_watcher_list )w);
589			ev_stop ((struct ev_watcher *)w);
590
591			++fdchangecnt;
592			array_needsize (fdchanges, fdchangemax, fdchangecnt, );
593			fdchanges [fdchangecnt - 1] = w->fd;
594			}
595
596			void
597			evtimer_start (struct ev_timer *w)
598			{
599			if (ev_is_active (w))
600			return;
601
602			if (w->is_abs)
603			{
604	root	1.2	/* this formula differs from the one in timer_reify becuse we do not round up */
605	root	1.1	if (w->repeat)
606			w->at += ceil ((ev_now - w->at) / w->repeat) * w->repeat;
607	root	1.4
608			ev_start ((struct ev_watcher *)w, ++atimercnt);
609			array_needsize (atimers, atimermax, atimercnt, );
610			atimers [atimercnt - 1] = w;
611			upheap (atimers, atimercnt - 1);
612	root	1.1	}
613			else
614	root	1.4	{
615			w->at += now;
616
617			ev_start ((struct ev_watcher *)w, ++rtimercnt);
618			array_needsize (rtimers, rtimermax, rtimercnt, );
619			rtimers [rtimercnt - 1] = w;
620			upheap (rtimers, rtimercnt - 1);
621			}
622	root	1.1
623			}
624
625			void
626			evtimer_stop (struct ev_timer *w)
627			{
628			if (!ev_is_active (w))
629			return;
630
631	root	1.4	if (w->is_abs)
632	root	1.2	{
633	root	1.4	if (w->active < atimercnt--)
634			{
635			atimers [w->active - 1] = atimers [atimercnt];
636			downheap (atimers, atimercnt, w->active - 1);
637			}
638			}
639			else
640			{
641			if (w->active < rtimercnt--)
642			{
643			rtimers [w->active - 1] = rtimers [rtimercnt];
644			downheap (rtimers, rtimercnt, w->active - 1);
645			}
646	root	1.2	}
647
648	root	1.1	ev_stop ((struct ev_watcher *)w);
649			}
650
651			void
652			evsignal_start (struct ev_signal *w)
653			{
654			if (ev_is_active (w))
655			return;
656
657			ev_start ((struct ev_watcher *)w, 1);
658			array_needsize (signals, signalmax, w->signum, signals_init);
659	root	1.7	wlist_add ((struct ev_watcher_list *)&signals [w->signum - 1].head, (struct ev_watcher_list )w);
660
661			if (!w->next)
662			{
663			struct sigaction sa;
664			sa.sa_handler = sighandler;
665			sigfillset (&sa.sa_mask);
666			sa.sa_flags = 0;
667			sigaction (w->signum, &sa, 0);
668			}
669	root	1.1	}
670
671			void
672			evsignal_stop (struct ev_signal *w)
673			{
674			if (!ev_is_active (w))
675			return;
676
677	root	1.7	wlist_del ((struct ev_watcher_list *)&signals [w->signum - 1].head, (struct ev_watcher_list )w);
678	root	1.1	ev_stop ((struct ev_watcher *)w);
679	root	1.7
680			if (!signals [w->signum - 1].head)
681			signal (w->signum, SIG_DFL);
682	root	1.1	}
683
684			/*****************************************************************************/
685			#if 1
686
687			static void
688			sin_cb (struct ev_io *w, int revents)
689			{
690			fprintf (stderr, "sin %d, revents %d\n", w->fd, revents);
691			}
692
693			static void
694			ocb (struct ev_timer *w, int revents)
695			{
696	root	1.4	//fprintf (stderr, "timer %f,%f (%x) (%f) d%p\n", w->at, w->repeat, revents, w->at - ev_time (), w->data);
697			evtimer_stop (w);
698			evtimer_start (w);
699	root	1.1	}
700
701	root	1.7	static void
702			scb (struct ev_signal *w, int revents)
703			{
704			fprintf (stderr, "signal %x,%d\n", revents, w->signum);
705			}
706
707	root	1.1	int main (void)
708			{
709			struct ev_io sin;
710
711			ev_init (0);
712
713			evw_init (&sin, sin_cb, 55);
714			evio_set (&sin, 0, EV_READ);
715			evio_start (&sin);
716
717	root	1.4	struct ev_timer t[10000];
718	root	1.2
719	root	1.8	#if 1
720	root	1.2	int i;
721	root	1.4	for (i = 0; i < 10000; ++i)
722	root	1.2	{
723			struct ev_timer *w = t + i;
724			evw_init (w, ocb, i);
725	root	1.4	evtimer_set_abs (w, drand48 (), 0.99775533);
726	root	1.2	evtimer_start (w);
727			if (drand48 () < 0.5)
728			evtimer_stop (w);
729			}
730	root	1.4	#endif
731
732			struct ev_timer t1;
733			evw_init (&t1, ocb, 0);
734			evtimer_set_abs (&t1, 5, 10);
735			evtimer_start (&t1);
736	root	1.1
737	root	1.7	struct ev_signal sig;
738			evw_init (&sig, scb, 65535);
739			evsignal_set (&sig, SIGQUIT);
740			evsignal_start (&sig);
741
742	root	1.1	ev_loop (0);
743
744			return 0;
745			}
746
747			#endif
748
749
750
751