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>

#define HAVE_EPOLL 1

#ifndef HAVE_MONOTONIC
# ifdef CLOCK_MONOTONIC
#  define HAVE_MONOTONIC 1
# endif
#endif

#ifndef HAVE_SELECT
# define HAVE_SELECT 1
#endif

#ifndef HAVE_EPOLL
# define HAVE_EPOLL 0
#endif

#ifndef HAVE_REALTIME
# define HAVE_REALTIME 1 /* posix requirement, but might be slower */
#endif

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

#include "ev.h"

typedef struct ev_watcher *W;
typedef struct ev_watcher_list *WL;
typedef struct ev_watcher_time *WT;

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;                 \
      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
{
  W w;
  int events;
} ANPENDING;

static ANPENDING *pendings;
static int pendingmax, pendingcnt;

static void
event (W 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 ((W)w, ev);
    }
}

static void
queue_events (W *events, int eventcnt, int type)
{
  int i;

  for (i = 0; i < eventcnt; ++i)
    event (events [i], type);
}

/*****************************************************************************/

static struct ev_timer **timers;
static int timermax, timercnt;

static struct ev_periodic **periodics;
static int periodicmax, periodiccnt;

static void
upheap (WT *timers, int k)
{
  WT 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 (WT *timers, int N, int k)
{
  WT 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 ((W)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);
}

/*****************************************************************************/

static struct ev_idle **idles;
static int idlemax, idlecnt;

static struct ev_check **checks;
static int checkmax, checkcnt;

/*****************************************************************************/

#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);
      siginit ();
    }

  return ev_method;
}

/*****************************************************************************/

void ev_prefork (void)
{
  /* nop */
}

void ev_postfork_parent (void)
{
  /* nop */
}

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 ()
{
  while (timercnt && timers [0]->at <= now)
    {
      struct ev_timer *w = timers [0];

      /* first reschedule or stop timer */
      if (w->repeat)
        {
          w->at = now + w->repeat;
          assert (("timer timeout in the past, negative repeat?", w->at > now));
          downheap ((WT *)timers, timercnt, 0);
        }
      else
        evtimer_stop (w); /* nonrepeating: stop timer */

      event ((W)w, EV_TIMEOUT);
    }
}

static void
periodics_reify ()
{
  while (periodiccnt && periodics [0]->at <= ev_now)
    {
      struct ev_periodic *w = periodics [0];

      /* first reschedule or stop timer */
      if (w->interval)
        {
          w->at += floor ((ev_now - w->at) / w->interval + 1.) * w->interval;
          assert (("periodic timeout in the past, negative interval?", w->at > ev_now));
          downheap ((WT *)periodics, periodiccnt, 0);
        }
      else
        evperiodic_stop (w); /* nonrepeating: stop timer */

      event ((W)w, EV_TIMEOUT);
    }
}

static void
periodics_reschedule (ev_tstamp diff)
{
  int i;

  /* adjust periodics after time jump */
  for (i = 0; i < periodiccnt; ++i)
    {
      struct ev_periodic *w = periodics [i];

      if (w->interval)
        {
          ev_tstamp diff = ceil ((ev_now - w->at) / w->interval) * w->interval;

          if (fabs (diff) >= 1e-4)
            {
              evperiodic_stop (w);
              evperiodic_start (w);

              i = 0; /* restart loop, inefficient, but time jumps should be rare */
            }
        }
    }
}

static void
time_update ()
{
  int i;

  ev_now = ev_time ();

  if (have_monotonic)
    {
      ev_tstamp odiff = diff;

      for (i = 4; --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 ();
        }

      periodics_reschedule (diff - odiff);
      /* no timer adjustment, as the monotonic clock doesn't jump */
    }
  else
    {
      if (now > ev_now || now < ev_now - MAX_BLOCKTIME - MIN_TIMEJUMP)
        {
          periodics_reschedule (ev_now - now);

          /* adjust timers. this is easy, as the offset is the same for all */
          for (i = 0; i < timercnt; ++i)
            timers [i]->at += diff;
        }

      now = ev_now;
    }
}

int ev_loop_done;

void ev_loop (int flags)
{
  double block;
  ev_loop_done = flags & EVLOOP_ONESHOT ? 1 : 0;

  if (checkcnt)
    {
      queue_events ((W *)checks, checkcnt, EV_CHECK);
      call_pending ();
    }

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

      /* calculate blocking time */

      /* we only need this for !monotonic clock, but as we always have timers, we just calculate it every time */
      ev_now = ev_time ();

      if (flags & EVLOOP_NONBLOCK || idlecnt)
        block = 0.;
      else
        {
          block = MAX_BLOCKTIME;

          if (timercnt)
            {
              ev_tstamp to = timers [0]->at - (have_monotonic ? get_clock () : ev_now) + method_fudge;
              if (block > to) block = to;
            }

          if (periodiccnt)
            {
              ev_tstamp to = periodics [0]->at - ev_now + method_fudge;
              if (block > to) block = to;
            }

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

      method_poll (block);

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

      /* queue pending timers and reschedule them */
      periodics_reify (); /* absolute timers first */
      timers_reify (); /* relative timers second */

      /* queue idle watchers unless io or timers are pending */
      if (!pendingcnt)
        queue_events ((W *)idles, idlecnt, EV_IDLE);

      /* queue check and possibly idle watchers */
      queue_events ((W *)checks, checkcnt, EV_CHECK);

      call_pending ();
    }
  while (!ev_loop_done);

  if (ev_loop_done != 2)
    ev_loop_done = 0;
}

/*****************************************************************************/

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

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

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

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

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

  w->active = 0;
}

/*****************************************************************************/

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

  int fd = w->fd;

  ev_start ((W)w, 1);
  array_needsize (anfds, anfdmax, fd + 1, anfds_init);
  wlist_add ((WL *)&anfds[fd].head, (WL)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 ((WL *)&anfds[w->fd].head, (WL)w);
  ev_stop ((W)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;

  w->at += now;

  assert (("timer repeat value less than zero not allowed", w->repeat >= 0.));

  ev_start ((W)w, ++timercnt);
  array_needsize (timers, timermax, timercnt, );
  timers [timercnt - 1] = w;
  upheap ((WT *)timers, timercnt - 1);
}

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

  if (w->active < timercnt--)
    {
      timers [w->active - 1] = timers [timercnt];
      downheap ((WT *)timers, timercnt, w->active - 1);
    }

  w->at = w->repeat;

  ev_stop ((W)w);
}

void
evtimer_again (struct ev_timer *w)
{
  if (ev_is_active (w))
    {
      if (w->repeat)
        {
          w->at = now + w->repeat;
          downheap ((WT *)timers, timercnt, w->active - 1);
        }
      else
        evtimer_stop (w);
    }
  else if (w->repeat)
    evtimer_start (w);
}

void
evperiodic_start (struct ev_periodic *w)
{
  if (ev_is_active (w))
    return;

  assert (("periodic interval value less than zero not allowed", w->interval >= 0.));

  /* this formula differs from the one in periodic_reify because we do not always round up */
  if (w->interval)
    w->at += ceil ((ev_now - w->at) / w->interval) * w->interval;

  ev_start ((W)w, ++periodiccnt);
  array_needsize (periodics, periodicmax, periodiccnt, );
  periodics [periodiccnt - 1] = w;
  upheap ((WT *)periodics, periodiccnt - 1);
}

void
evperiodic_stop (struct ev_periodic *w)
{
  if (!ev_is_active (w))
    return;

  if (w->active < periodiccnt--)
    {
      periodics [w->active - 1] = periodics [periodiccnt];
      downheap ((WT *)periodics, periodiccnt, w->active - 1);
    }

  ev_stop ((W)w);
}

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

  ev_start ((W)w, 1);
  array_needsize (signals, signalmax, w->signum, signals_init);
  wlist_add ((WL *)&signals [w->signum - 1].head, (WL)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 ((WL *)&signals [w->signum - 1].head, (WL)w);
  ev_stop ((W)w);

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

void evidle_start (struct ev_idle *w)
{
  if (ev_is_active (w))
    return;

  ev_start ((W)w, ++idlecnt);
  array_needsize (idles, idlemax, idlecnt, );
  idles [idlecnt - 1] = w;
}

void evidle_stop (struct ev_idle *w)
{
  idles [w->active - 1] = idles [--idlecnt];
  ev_stop ((W)w);
}

void evcheck_start (struct ev_check *w)
{
  if (ev_is_active (w))
    return;

  ev_start ((W)w, ++checkcnt);
  array_needsize (checks, checkmax, checkcnt, );
  checks [checkcnt - 1] = w;
}

void evcheck_stop (struct ev_check *w)
{
  checks [w->active - 1] = checks [--checkcnt];
  ev_stop ((W)w);
}

/*****************************************************************************/

#if 0

struct ev_io wio;

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);
  evio_stop (&wio);
  evio_start (&wio);
}

static void
gcb (struct ev_signal *w, int revents)
{
  fprintf (stderr, "generic %x\n", revents);

}

int main (void)
{
  ev_init (0);

  evio_init (&wio, sin_cb, 0, EV_READ);
  evio_start (&wio);

  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_init_abs (w, ocb, drand48 (), 0.99775533);
      evtimer_start (w);
      if (drand48 () < 0.5)
        evtimer_stop (w);
    }
#endif

  struct ev_timer t1;
  evtimer_init (&t1, ocb, 5, 10);
  evtimer_start (&t1);

  struct ev_signal sig;
  evsignal_init (&sig, scb, SIGQUIT);
  evsignal_start (&sig);

  struct ev_check cw;
  evcheck_init (&cw, gcb);
  evcheck_start (&cw);

  struct ev_idle iw;
  evidle_init (&iw, gcb);
  evidle_start (&iw);

  ev_loop (0);

  return 0;
}

#endif


Revision:	1.15
Committed:	Wed Oct 31 11:56:34 2007 UTC (16 years, 6 months ago) by root
Content type:	text/plain
Branch:	MAIN
Changes since 1.14:	+0 -1 lines
Log Message:	rmeove remaining debugging code
#	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	root	1.12	#define HAVE_EPOLL 1
15
16	root	1.10	#ifndef HAVE_MONOTONIC
17			# ifdef CLOCK_MONOTONIC
18			# define HAVE_MONOTONIC 1
19			# endif
20	root	1.1	#endif
21
22	root	1.10	#ifndef HAVE_SELECT
23			# define HAVE_SELECT 1
24			#endif
25
26			#ifndef HAVE_EPOLL
27			# define HAVE_EPOLL 0
28			#endif
29
30			#ifndef HAVE_REALTIME
31			# define HAVE_REALTIME 1 /* posix requirement, but might be slower */
32			#endif
33	root	1.1
34	root	1.4	#define MIN_TIMEJUMP 1. /* minimum timejump that gets detected (if monotonic clock available) */
35	root	1.1	#define MAX_BLOCKTIME 60.
36
37			#include "ev.h"
38
39	root	1.10	typedef struct ev_watcher *W;
40			typedef struct ev_watcher_list *WL;
41	root	1.12	typedef struct ev_watcher_time *WT;
42	root	1.10
43	root	1.4	static ev_tstamp now, diff; /* monotonic clock */
44	root	1.1	ev_tstamp ev_now;
45			int ev_method;
46
47			static int have_monotonic; /* runtime */
48
49			static ev_tstamp method_fudge; /* stupid epoll-returns-early bug */
50	root	1.5	static void (*method_modify)(int fd, int oev, int nev);
51	root	1.1	static void (*method_poll)(ev_tstamp timeout);
52
53	root	1.8	/*****************************************************************************/
54
55	root	1.1	ev_tstamp
56			ev_time (void)
57			{
58			#if HAVE_REALTIME
59			struct timespec ts;
60			clock_gettime (CLOCK_REALTIME, &ts);
61			return ts.tv_sec + ts.tv_nsec * 1e-9;
62			#else
63			struct timeval tv;
64			gettimeofday (&tv, 0);
65			return tv.tv_sec + tv.tv_usec * 1e-6;
66			#endif
67			}
68
69			static ev_tstamp
70			get_clock (void)
71			{
72			#if HAVE_MONOTONIC
73			if (have_monotonic)
74			{
75			struct timespec ts;
76			clock_gettime (CLOCK_MONOTONIC, &ts);
77			return ts.tv_sec + ts.tv_nsec * 1e-9;
78			}
79			#endif
80
81			return ev_time ();
82			}
83
84			#define array_needsize(base,cur,cnt,init) \
85			if ((cnt) > cur) \
86			{ \
87	root	1.2	int newcnt = cur ? cur << 1 : 16; \
88	root	1.1	base = realloc (base, sizeof (base) (newcnt)); \
89			init (base + cur, newcnt - cur); \
90			cur = newcnt; \
91			}
92
93	root	1.8	/*****************************************************************************/
94
95	root	1.1	typedef struct
96			{
97			struct ev_io *head;
98			unsigned char wev, rev; /* want, received event set */
99			} ANFD;
100
101			static ANFD *anfds;
102			static int anfdmax;
103
104			static int *fdchanges;
105			static int fdchangemax, fdchangecnt;
106
107			static void
108			anfds_init (ANFD *base, int count)
109			{
110			while (count--)
111			{
112			base->head = 0;
113			base->wev = base->rev = EV_NONE;
114			++base;
115			}
116			}
117
118			typedef struct
119			{
120	root	1.10	W w;
121	root	1.1	int events;
122			} ANPENDING;
123
124			static ANPENDING *pendings;
125			static int pendingmax, pendingcnt;
126
127			static void
128	root	1.10	event (W w, int events)
129	root	1.1	{
130			w->pending = ++pendingcnt;
131			array_needsize (pendings, pendingmax, pendingcnt, );
132			pendings [pendingcnt - 1].w = w;
133			pendings [pendingcnt - 1].events = events;
134			}
135
136			static void
137			fd_event (int fd, int events)
138			{
139			ANFD *anfd = anfds + fd;
140			struct ev_io *w;
141
142			for (w = anfd->head; w; w = w->next)
143			{
144			int ev = w->events & events;
145
146			if (ev)
147	root	1.10	event ((W)w, ev);
148	root	1.1	}
149			}
150
151	root	1.9	static void
152	root	1.10	queue_events (W *events, int eventcnt, int type)
153	root	1.9	{
154			int i;
155
156			for (i = 0; i < eventcnt; ++i)
157			event (events [i], type);
158			}
159
160	root	1.8	/*****************************************************************************/
161
162	root	1.12	static struct ev_timer **timers;
163			static int timermax, timercnt;
164	root	1.4
165	root	1.12	static struct ev_periodic **periodics;
166			static int periodicmax, periodiccnt;
167	root	1.1
168			static void
169	root	1.12	upheap (WT *timers, int k)
170	root	1.1	{
171	root	1.12	WT w = timers [k];
172	root	1.1
173			while (k && timers [k >> 1]->at > w->at)
174			{
175			timers [k] = timers [k >> 1];
176			timers [k]->active = k + 1;
177			k >>= 1;
178			}
179
180			timers [k] = w;
181			timers [k]->active = k + 1;
182
183			}
184
185			static void
186	root	1.12	downheap (WT *timers, int N, int k)
187	root	1.1	{
188	root	1.12	WT w = timers [k];
189	root	1.1
190	root	1.4	while (k < (N >> 1))
191	root	1.1	{
192			int j = k << 1;
193
194	root	1.4	if (j + 1 < N && timers [j]->at > timers [j + 1]->at)
195	root	1.1	++j;
196
197			if (w->at <= timers [j]->at)
198			break;
199
200			timers [k] = timers [j];
201	root	1.2	timers [k]->active = k + 1;
202	root	1.1	k = j;
203			}
204
205			timers [k] = w;
206			timers [k]->active = k + 1;
207			}
208
209	root	1.8	/*****************************************************************************/
210
211	root	1.7	typedef struct
212			{
213			struct ev_signal *head;
214			sig_atomic_t gotsig;
215			} ANSIG;
216
217			static ANSIG *signals;
218	root	1.4	static int signalmax;
219	root	1.1
220	root	1.7	static int sigpipe [2];
221			static sig_atomic_t gotsig;
222			static struct ev_io sigev;
223
224	root	1.1	static void
225	root	1.7	signals_init (ANSIG *base, int count)
226	root	1.1	{
227			while (count--)
228	root	1.7	{
229			base->head = 0;
230			base->gotsig = 0;
231			++base;
232			}
233			}
234
235			static void
236			sighandler (int signum)
237			{
238			signals [signum - 1].gotsig = 1;
239
240			if (!gotsig)
241			{
242			gotsig = 1;
243			write (sigpipe [1], &gotsig, 1);
244			}
245			}
246
247			static void
248			sigcb (struct ev_io *iow, int revents)
249			{
250			struct ev_signal *w;
251			int sig;
252
253			gotsig = 0;
254			read (sigpipe [0], &revents, 1);
255
256			for (sig = signalmax; sig--; )
257			if (signals [sig].gotsig)
258			{
259			signals [sig].gotsig = 0;
260
261			for (w = signals [sig].head; w; w = w->next)
262	root	1.10	event ((W)w, EV_SIGNAL);
263	root	1.7	}
264			}
265
266			static void
267			siginit (void)
268			{
269			fcntl (sigpipe [0], F_SETFD, FD_CLOEXEC);
270			fcntl (sigpipe [1], F_SETFD, FD_CLOEXEC);
271
272			/* rather than sort out wether we really need nb, set it */
273			fcntl (sigpipe [0], F_SETFL, O_NONBLOCK);
274			fcntl (sigpipe [1], F_SETFL, O_NONBLOCK);
275
276			evio_set (&sigev, sigpipe [0], EV_READ);
277			evio_start (&sigev);
278	root	1.1	}
279
280	root	1.8	/*****************************************************************************/
281
282	root	1.9	static struct ev_idle **idles;
283			static int idlemax, idlecnt;
284
285			static struct ev_check **checks;
286			static int checkmax, checkcnt;
287
288			/*****************************************************************************/
289
290	root	1.1	#if HAVE_EPOLL
291			# include "ev_epoll.c"
292			#endif
293			#if HAVE_SELECT
294			# include "ev_select.c"
295			#endif
296
297			int ev_init (int flags)
298			{
299			#if HAVE_MONOTONIC
300			{
301			struct timespec ts;
302			if (!clock_gettime (CLOCK_MONOTONIC, &ts))
303			have_monotonic = 1;
304			}
305			#endif
306
307			ev_now = ev_time ();
308	root	1.4	now = get_clock ();
309			diff = ev_now - now;
310	root	1.1
311	root	1.7	if (pipe (sigpipe))
312			return 0;
313
314			ev_method = EVMETHOD_NONE;
315	root	1.1	#if HAVE_EPOLL
316	root	1.7	if (ev_method == EVMETHOD_NONE) epoll_init (flags);
317	root	1.1	#endif
318			#if HAVE_SELECT
319	root	1.7	if (ev_method == EVMETHOD_NONE) select_init (flags);
320	root	1.1	#endif
321
322	root	1.7	if (ev_method)
323			{
324	root	1.12	evw_init (&sigev, sigcb);
325	root	1.7	siginit ();
326			}
327
328	root	1.1	return ev_method;
329			}
330
331	root	1.8	/*****************************************************************************/
332
333	root	1.1	void ev_prefork (void)
334			{
335	root	1.11	/* nop */
336	root	1.1	}
337
338			void ev_postfork_parent (void)
339			{
340	root	1.11	/* nop */
341	root	1.1	}
342
343			void ev_postfork_child (void)
344			{
345			#if HAVE_EPOLL
346	root	1.5	if (ev_method == EVMETHOD_EPOLL)
347			epoll_postfork_child ();
348	root	1.1	#endif
349	root	1.7
350			evio_stop (&sigev);
351			close (sigpipe [0]);
352			close (sigpipe [1]);
353			pipe (sigpipe);
354			siginit ();
355	root	1.1	}
356
357	root	1.8	/*****************************************************************************/
358
359	root	1.1	static void
360	root	1.5	fd_reify (void)
361			{
362			int i;
363
364			for (i = 0; i < fdchangecnt; ++i)
365			{
366			int fd = fdchanges [i];
367			ANFD *anfd = anfds + fd;
368			struct ev_io *w;
369
370			int wev = 0;
371
372			for (w = anfd->head; w; w = w->next)
373			wev \|= w->events;
374
375			if (anfd->wev != wev)
376			{
377			method_modify (fd, anfd->wev, wev);
378			anfd->wev = wev;
379			}
380			}
381
382			fdchangecnt = 0;
383			}
384
385			static void
386	root	1.1	call_pending ()
387			{
388			int i;
389
390			for (i = 0; i < pendingcnt; ++i)
391			{
392			ANPENDING *p = pendings + i;
393
394			if (p->w)
395			{
396			p->w->pending = 0;
397			p->w->cb (p->w, p->events);
398			}
399			}
400
401			pendingcnt = 0;
402			}
403
404			static void
405	root	1.12	timers_reify ()
406	root	1.1	{
407	root	1.4	while (timercnt && timers [0]->at <= now)
408	root	1.1	{
409			struct ev_timer *w = timers [0];
410
411	root	1.4	/* first reschedule or stop timer */
412	root	1.1	if (w->repeat)
413			{
414	root	1.12	w->at = now + w->repeat;
415			assert (("timer timeout in the past, negative repeat?", w->at > now));
416			downheap ((WT *)timers, timercnt, 0);
417			}
418			else
419			evtimer_stop (w); /* nonrepeating: stop timer */
420
421			event ((W)w, EV_TIMEOUT);
422			}
423			}
424	root	1.4
425	root	1.12	static void
426			periodics_reify ()
427			{
428			while (periodiccnt && periodics [0]->at <= ev_now)
429			{
430			struct ev_periodic *w = periodics [0];
431	root	1.1
432	root	1.12	/* first reschedule or stop timer */
433			if (w->interval)
434			{
435			w->at += floor ((ev_now - w->at) / w->interval + 1.) * w->interval;
436			assert (("periodic timeout in the past, negative interval?", w->at > ev_now));
437			downheap ((WT *)periodics, periodiccnt, 0);
438	root	1.1	}
439			else
440	root	1.12	evperiodic_stop (w); /* nonrepeating: stop timer */
441
442			event ((W)w, EV_TIMEOUT);
443			}
444			}
445
446			static void
447	root	1.13	periodics_reschedule (ev_tstamp diff)
448	root	1.12	{
449			int i;
450
451	root	1.13	/* adjust periodics after time jump */
452	root	1.12	for (i = 0; i < periodiccnt; ++i)
453			{
454			struct ev_periodic *w = periodics [i];
455
456			if (w->interval)
457	root	1.4	{
458	root	1.12	ev_tstamp diff = ceil ((ev_now - w->at) / w->interval) * w->interval;
459
460			if (fabs (diff) >= 1e-4)
461			{
462			evperiodic_stop (w);
463			evperiodic_start (w);
464
465			i = 0; /* restart loop, inefficient, but time jumps should be rare */
466			}
467	root	1.4	}
468	root	1.12	}
469	root	1.1	}
470
471	root	1.4	static void
472			time_update ()
473			{
474			int i;
475	root	1.12
476	root	1.4	ev_now = ev_time ();
477
478			if (have_monotonic)
479			{
480			ev_tstamp odiff = diff;
481
482	root	1.12	for (i = 4; --i; ) /* loop a few times, before making important decisions */
483	root	1.4	{
484			now = get_clock ();
485			diff = ev_now - now;
486
487			if (fabs (odiff - diff) < MIN_TIMEJUMP)
488			return; /* all is well */
489
490			ev_now = ev_time ();
491			}
492
493	root	1.13	periodics_reschedule (diff - odiff);
494			/* no timer adjustment, as the monotonic clock doesn't jump */
495	root	1.4	}
496			else
497			{
498			if (now > ev_now \|\| now < ev_now - MAX_BLOCKTIME - MIN_TIMEJUMP)
499	root	1.13	{
500			periodics_reschedule (ev_now - now);
501
502			/* adjust timers. this is easy, as the offset is the same for all */
503			for (i = 0; i < timercnt; ++i)
504			timers [i]->at += diff;
505			}
506	root	1.4
507			now = ev_now;
508			}
509			}
510
511	root	1.1	int ev_loop_done;
512
513	root	1.4	void ev_loop (int flags)
514	root	1.1	{
515			double block;
516	root	1.13	ev_loop_done = flags & EVLOOP_ONESHOT ? 1 : 0;
517	root	1.1
518	root	1.9	if (checkcnt)
519			{
520	root	1.10	queue_events ((W *)checks, checkcnt, EV_CHECK);
521	root	1.9	call_pending ();
522			}
523
524	root	1.1	do
525			{
526			/* update fd-related kernel structures */
527	root	1.5	fd_reify ();
528	root	1.1
529			/* calculate blocking time */
530	root	1.12
531			/* we only need this for !monotonic clock, but as we always have timers, we just calculate it every time */
532			ev_now = ev_time ();
533
534	root	1.9	if (flags & EVLOOP_NONBLOCK \|\| idlecnt)
535	root	1.1	block = 0.;
536			else
537			{
538	root	1.4	block = MAX_BLOCKTIME;
539
540	root	1.12	if (timercnt)
541	root	1.4	{
542	root	1.14	ev_tstamp to = timers [0]->at - (have_monotonic ? get_clock () : ev_now) + method_fudge;
543	root	1.4	if (block > to) block = to;
544			}
545
546	root	1.12	if (periodiccnt)
547	root	1.4	{
548	root	1.12	ev_tstamp to = periodics [0]->at - ev_now + method_fudge;
549	root	1.4	if (block > to) block = to;
550			}
551
552	root	1.1	if (block < 0.) block = 0.;
553			}
554
555			method_poll (block);
556
557	root	1.4	/* update ev_now, do magic */
558			time_update ();
559
560	root	1.9	/* queue pending timers and reschedule them */
561	root	1.12	periodics_reify (); /* absolute timers first */
562			timers_reify (); /* relative timers second */
563	root	1.1
564	root	1.9	/* queue idle watchers unless io or timers are pending */
565			if (!pendingcnt)
566	root	1.10	queue_events ((W *)idles, idlecnt, EV_IDLE);
567	root	1.9
568			/* queue check and possibly idle watchers */
569	root	1.10	queue_events ((W *)checks, checkcnt, EV_CHECK);
570	root	1.9
571	root	1.1	call_pending ();
572			}
573			while (!ev_loop_done);
574	root	1.13
575			if (ev_loop_done != 2)
576			ev_loop_done = 0;
577	root	1.1	}
578
579	root	1.8	/*****************************************************************************/
580
581	root	1.1	static void
582	root	1.10	wlist_add (WL *head, WL elem)
583	root	1.1	{
584			elem->next = *head;
585			*head = elem;
586			}
587
588			static void
589	root	1.10	wlist_del (WL *head, WL elem)
590	root	1.1	{
591			while (*head)
592			{
593			if (*head == elem)
594			{
595			*head = elem->next;
596			return;
597			}
598
599			head = &(*head)->next;
600			}
601			}
602
603			static void
604	root	1.10	ev_start (W w, int active)
605	root	1.1	{
606			w->pending = 0;
607			w->active = active;
608			}
609
610			static void
611	root	1.10	ev_stop (W w)
612	root	1.1	{
613			if (w->pending)
614			pendings [w->pending - 1].w = 0;
615
616			w->active = 0;
617			}
618
619	root	1.8	/*****************************************************************************/
620
621	root	1.1	void
622			evio_start (struct ev_io *w)
623			{
624			if (ev_is_active (w))
625			return;
626
627			int fd = w->fd;
628
629	root	1.10	ev_start ((W)w, 1);
630	root	1.1	array_needsize (anfds, anfdmax, fd + 1, anfds_init);
631	root	1.10	wlist_add ((WL *)&anfds[fd].head, (WL)w);
632	root	1.1
633			++fdchangecnt;
634			array_needsize (fdchanges, fdchangemax, fdchangecnt, );
635			fdchanges [fdchangecnt - 1] = fd;
636			}
637
638			void
639			evio_stop (struct ev_io *w)
640			{
641			if (!ev_is_active (w))
642			return;
643
644	root	1.10	wlist_del ((WL *)&anfds[w->fd].head, (WL)w);
645			ev_stop ((W)w);
646	root	1.1
647			++fdchangecnt;
648			array_needsize (fdchanges, fdchangemax, fdchangecnt, );
649			fdchanges [fdchangecnt - 1] = w->fd;
650			}
651
652	root	1.12
653	root	1.1	void
654			evtimer_start (struct ev_timer *w)
655			{
656			if (ev_is_active (w))
657			return;
658
659	root	1.12	w->at += now;
660
661	root	1.13	assert (("timer repeat value less than zero not allowed", w->repeat >= 0.));
662
663	root	1.12	ev_start ((W)w, ++timercnt);
664			array_needsize (timers, timermax, timercnt, );
665			timers [timercnt - 1] = w;
666			upheap ((WT *)timers, timercnt - 1);
667			}
668
669			void
670			evtimer_stop (struct ev_timer *w)
671			{
672			if (!ev_is_active (w))
673			return;
674
675			if (w->active < timercnt--)
676	root	1.1	{
677	root	1.12	timers [w->active - 1] = timers [timercnt];
678			downheap ((WT *)timers, timercnt, w->active - 1);
679			}
680	root	1.4
681	root	1.14	w->at = w->repeat;
682
683	root	1.12	ev_stop ((W)w);
684			}
685	root	1.4
686	root	1.12	void
687	root	1.14	evtimer_again (struct ev_timer *w)
688			{
689			if (ev_is_active (w))
690			{
691			if (w->repeat)
692			{
693			w->at = now + w->repeat;
694			downheap ((WT *)timers, timercnt, w->active - 1);
695			}
696			else
697			evtimer_stop (w);
698			}
699			else if (w->repeat)
700			evtimer_start (w);
701			}
702
703			void
704	root	1.12	evperiodic_start (struct ev_periodic *w)
705			{
706			if (ev_is_active (w))
707			return;
708	root	1.1
709	root	1.13	assert (("periodic interval value less than zero not allowed", w->interval >= 0.));
710
711	root	1.12	/* this formula differs from the one in periodic_reify because we do not always round up */
712			if (w->interval)
713			w->at += ceil ((ev_now - w->at) / w->interval) * w->interval;
714
715			ev_start ((W)w, ++periodiccnt);
716			array_needsize (periodics, periodicmax, periodiccnt, );
717			periodics [periodiccnt - 1] = w;
718			upheap ((WT *)periodics, periodiccnt - 1);
719	root	1.1	}
720
721			void
722	root	1.12	evperiodic_stop (struct ev_periodic *w)
723	root	1.1	{
724			if (!ev_is_active (w))
725			return;
726
727	root	1.12	if (w->active < periodiccnt--)
728	root	1.2	{
729	root	1.12	periodics [w->active - 1] = periodics [periodiccnt];
730			downheap ((WT *)periodics, periodiccnt, w->active - 1);
731	root	1.2	}
732
733	root	1.10	ev_stop ((W)w);
734	root	1.1	}
735
736			void
737			evsignal_start (struct ev_signal *w)
738			{
739			if (ev_is_active (w))
740			return;
741
742	root	1.10	ev_start ((W)w, 1);
743	root	1.1	array_needsize (signals, signalmax, w->signum, signals_init);
744	root	1.10	wlist_add ((WL *)&signals [w->signum - 1].head, (WL)w);
745	root	1.7
746			if (!w->next)
747			{
748			struct sigaction sa;
749			sa.sa_handler = sighandler;
750			sigfillset (&sa.sa_mask);
751			sa.sa_flags = 0;
752			sigaction (w->signum, &sa, 0);
753			}
754	root	1.1	}
755
756			void
757			evsignal_stop (struct ev_signal *w)
758			{
759			if (!ev_is_active (w))
760			return;
761
762	root	1.10	wlist_del ((WL *)&signals [w->signum - 1].head, (WL)w);
763			ev_stop ((W)w);
764	root	1.7
765			if (!signals [w->signum - 1].head)
766			signal (w->signum, SIG_DFL);
767	root	1.1	}
768
769	root	1.9	void evidle_start (struct ev_idle *w)
770			{
771			if (ev_is_active (w))
772			return;
773
774	root	1.10	ev_start ((W)w, ++idlecnt);
775	root	1.9	array_needsize (idles, idlemax, idlecnt, );
776			idles [idlecnt - 1] = w;
777			}
778
779			void evidle_stop (struct ev_idle *w)
780			{
781			idles [w->active - 1] = idles [--idlecnt];
782	root	1.10	ev_stop ((W)w);
783	root	1.9	}
784
785			void evcheck_start (struct ev_check *w)
786			{
787			if (ev_is_active (w))
788			return;
789
790	root	1.10	ev_start ((W)w, ++checkcnt);
791	root	1.9	array_needsize (checks, checkmax, checkcnt, );
792			checks [checkcnt - 1] = w;
793			}
794
795			void evcheck_stop (struct ev_check *w)
796			{
797			checks [w->active - 1] = checks [--checkcnt];
798	root	1.10	ev_stop ((W)w);
799	root	1.9	}
800
801	root	1.1	/*****************************************************************************/
802	root	1.10
803	root	1.13	#if 0
804	root	1.12
805			struct ev_io wio;
806	root	1.1
807			static void
808			sin_cb (struct ev_io *w, int revents)
809			{
810			fprintf (stderr, "sin %d, revents %d\n", w->fd, revents);
811			}
812
813			static void
814			ocb (struct ev_timer *w, int revents)
815			{
816	root	1.4	//fprintf (stderr, "timer %f,%f (%x) (%f) d%p\n", w->at, w->repeat, revents, w->at - ev_time (), w->data);
817			evtimer_stop (w);
818			evtimer_start (w);
819	root	1.1	}
820
821	root	1.7	static void
822			scb (struct ev_signal *w, int revents)
823			{
824			fprintf (stderr, "signal %x,%d\n", revents, w->signum);
825	root	1.12	evio_stop (&wio);
826			evio_start (&wio);
827	root	1.7	}
828
829	root	1.9	static void
830			gcb (struct ev_signal *w, int revents)
831			{
832			fprintf (stderr, "generic %x\n", revents);
833	root	1.12
834	root	1.9	}
835
836	root	1.1	int main (void)
837			{
838			ev_init (0);
839
840	root	1.12	evio_init (&wio, sin_cb, 0, EV_READ);
841			evio_start (&wio);
842	root	1.1
843	root	1.4	struct ev_timer t[10000];
844	root	1.2
845	root	1.9	#if 0
846	root	1.2	int i;
847	root	1.4	for (i = 0; i < 10000; ++i)
848	root	1.2	{
849			struct ev_timer *w = t + i;
850			evw_init (w, ocb, i);
851	root	1.12	evtimer_init_abs (w, ocb, drand48 (), 0.99775533);
852	root	1.2	evtimer_start (w);
853			if (drand48 () < 0.5)
854			evtimer_stop (w);
855			}
856	root	1.4	#endif
857
858			struct ev_timer t1;
859	root	1.12	evtimer_init (&t1, ocb, 5, 10);
860	root	1.4	evtimer_start (&t1);
861	root	1.1
862	root	1.7	struct ev_signal sig;
863	root	1.12	evsignal_init (&sig, scb, SIGQUIT);
864	root	1.7	evsignal_start (&sig);
865
866	root	1.9	struct ev_check cw;
867	root	1.12	evcheck_init (&cw, gcb);
868	root	1.9	evcheck_start (&cw);
869
870			struct ev_idle iw;
871	root	1.12	evidle_init (&iw, gcb);
872	root	1.9	evidle_start (&iw);
873
874	root	1.1	ev_loop (0);
875
876			return 0;
877			}
878
879			#endif
880
881
882
883