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"

struct ev_watcher {
  EV_WATCHER (ev_watcher);
};

struct ev_watcher_list {
  EV_WATCHER_LIST (ev_watcher_list);
};

struct ev_watcher_time {
  EV_WATCHER_TIME (ev_watcher_time);
};

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;                 \
      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
{
  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
time_jump (ev_tstamp diff)
{
  int i;

  /* adjust periodics */
  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 */
            }
        }
    }

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

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 ();
        }

      time_jump (diff - odiff);
    }
  else
    {
      if (now > ev_now || now < ev_now - MAX_BLOCKTIME - MIN_TIMEJUMP)
        time_jump (ev_now - now);

      now = ev_now;
    }
}

int ev_loop_done;

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

  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 - get_clock () + 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);
}

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

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;

  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);
    }

  ev_stop ((W)w);
}

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

  /* 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 1

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:	1.12
Committed:	Wed Oct 31 09:23:17 2007 UTC (16 years, 6 months ago) by root
Content type:	text/plain
Branch:	MAIN
Changes since 1.11:	+134 -84 lines
Log Message:	* empty log message *
#	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			struct ev_watcher {
40			EV_WATCHER (ev_watcher);
41			};
42
43			struct ev_watcher_list {
44			EV_WATCHER_LIST (ev_watcher_list);
45			};
46
47	root	1.12	struct ev_watcher_time {
48			EV_WATCHER_TIME (ev_watcher_time);
49			};
50
51	root	1.10	typedef struct ev_watcher *W;
52			typedef struct ev_watcher_list *WL;
53	root	1.12	typedef struct ev_watcher_time *WT;
54	root	1.10
55	root	1.4	static ev_tstamp now, diff; /* monotonic clock */
56	root	1.1	ev_tstamp ev_now;
57			int ev_method;
58
59			static int have_monotonic; /* runtime */
60
61			static ev_tstamp method_fudge; /* stupid epoll-returns-early bug */
62	root	1.5	static void (*method_modify)(int fd, int oev, int nev);
63	root	1.1	static void (*method_poll)(ev_tstamp timeout);
64
65	root	1.8	/*****************************************************************************/
66
67	root	1.1	ev_tstamp
68			ev_time (void)
69			{
70			#if HAVE_REALTIME
71			struct timespec ts;
72			clock_gettime (CLOCK_REALTIME, &ts);
73			return ts.tv_sec + ts.tv_nsec * 1e-9;
74			#else
75			struct timeval tv;
76			gettimeofday (&tv, 0);
77			return tv.tv_sec + tv.tv_usec * 1e-6;
78			#endif
79			}
80
81			static ev_tstamp
82			get_clock (void)
83			{
84			#if HAVE_MONOTONIC
85			if (have_monotonic)
86			{
87			struct timespec ts;
88			clock_gettime (CLOCK_MONOTONIC, &ts);
89			return ts.tv_sec + ts.tv_nsec * 1e-9;
90			}
91			#endif
92
93			return ev_time ();
94			}
95
96			#define array_needsize(base,cur,cnt,init) \
97			if ((cnt) > cur) \
98			{ \
99	root	1.2	int newcnt = cur ? cur << 1 : 16; \
100	root	1.1	fprintf (stderr, "resize(" # base ") from %d to %d\n", cur, newcnt);\
101			base = realloc (base, sizeof (base) (newcnt)); \
102			init (base + cur, newcnt - cur); \
103			cur = newcnt; \
104			}
105
106	root	1.8	/*****************************************************************************/
107
108	root	1.1	typedef struct
109			{
110			struct ev_io *head;
111			unsigned char wev, rev; /* want, received event set */
112			} ANFD;
113
114			static ANFD *anfds;
115			static int anfdmax;
116
117			static int *fdchanges;
118			static int fdchangemax, fdchangecnt;
119
120			static void
121			anfds_init (ANFD *base, int count)
122			{
123			while (count--)
124			{
125			base->head = 0;
126			base->wev = base->rev = EV_NONE;
127			++base;
128			}
129			}
130
131			typedef struct
132			{
133	root	1.10	W w;
134	root	1.1	int events;
135			} ANPENDING;
136
137			static ANPENDING *pendings;
138			static int pendingmax, pendingcnt;
139
140			static void
141	root	1.10	event (W w, int events)
142	root	1.1	{
143			w->pending = ++pendingcnt;
144			array_needsize (pendings, pendingmax, pendingcnt, );
145			pendings [pendingcnt - 1].w = w;
146			pendings [pendingcnt - 1].events = events;
147			}
148
149			static void
150			fd_event (int fd, int events)
151			{
152			ANFD *anfd = anfds + fd;
153			struct ev_io *w;
154
155			for (w = anfd->head; w; w = w->next)
156			{
157			int ev = w->events & events;
158
159			if (ev)
160	root	1.10	event ((W)w, ev);
161	root	1.1	}
162			}
163
164	root	1.9	static void
165	root	1.10	queue_events (W *events, int eventcnt, int type)
166	root	1.9	{
167			int i;
168
169			for (i = 0; i < eventcnt; ++i)
170			event (events [i], type);
171			}
172
173	root	1.8	/*****************************************************************************/
174
175	root	1.12	static struct ev_timer **timers;
176			static int timermax, timercnt;
177	root	1.4
178	root	1.12	static struct ev_periodic **periodics;
179			static int periodicmax, periodiccnt;
180	root	1.1
181			static void
182	root	1.12	upheap (WT *timers, int k)
183	root	1.1	{
184	root	1.12	WT w = timers [k];
185	root	1.1
186			while (k && timers [k >> 1]->at > w->at)
187			{
188			timers [k] = timers [k >> 1];
189			timers [k]->active = k + 1;
190			k >>= 1;
191			}
192
193			timers [k] = w;
194			timers [k]->active = k + 1;
195
196			}
197
198			static void
199	root	1.12	downheap (WT *timers, int N, int k)
200	root	1.1	{
201	root	1.12	WT w = timers [k];
202	root	1.1
203	root	1.4	while (k < (N >> 1))
204	root	1.1	{
205			int j = k << 1;
206
207	root	1.4	if (j + 1 < N && timers [j]->at > timers [j + 1]->at)
208	root	1.1	++j;
209
210			if (w->at <= timers [j]->at)
211			break;
212
213			timers [k] = timers [j];
214	root	1.2	timers [k]->active = k + 1;
215	root	1.1	k = j;
216			}
217
218			timers [k] = w;
219			timers [k]->active = k + 1;
220			}
221
222	root	1.8	/*****************************************************************************/
223
224	root	1.7	typedef struct
225			{
226			struct ev_signal *head;
227			sig_atomic_t gotsig;
228			} ANSIG;
229
230			static ANSIG *signals;
231	root	1.4	static int signalmax;
232	root	1.1
233	root	1.7	static int sigpipe [2];
234			static sig_atomic_t gotsig;
235			static struct ev_io sigev;
236
237	root	1.1	static void
238	root	1.7	signals_init (ANSIG *base, int count)
239	root	1.1	{
240			while (count--)
241	root	1.7	{
242			base->head = 0;
243			base->gotsig = 0;
244			++base;
245			}
246			}
247
248			static void
249			sighandler (int signum)
250			{
251			signals [signum - 1].gotsig = 1;
252
253			if (!gotsig)
254			{
255			gotsig = 1;
256			write (sigpipe [1], &gotsig, 1);
257			}
258			}
259
260			static void
261			sigcb (struct ev_io *iow, int revents)
262			{
263			struct ev_signal *w;
264			int sig;
265
266			gotsig = 0;
267			read (sigpipe [0], &revents, 1);
268
269			for (sig = signalmax; sig--; )
270			if (signals [sig].gotsig)
271			{
272			signals [sig].gotsig = 0;
273
274			for (w = signals [sig].head; w; w = w->next)
275	root	1.10	event ((W)w, EV_SIGNAL);
276	root	1.7	}
277			}
278
279			static void
280			siginit (void)
281			{
282			fcntl (sigpipe [0], F_SETFD, FD_CLOEXEC);
283			fcntl (sigpipe [1], F_SETFD, FD_CLOEXEC);
284
285			/* rather than sort out wether we really need nb, set it */
286			fcntl (sigpipe [0], F_SETFL, O_NONBLOCK);
287			fcntl (sigpipe [1], F_SETFL, O_NONBLOCK);
288
289			evio_set (&sigev, sigpipe [0], EV_READ);
290			evio_start (&sigev);
291	root	1.1	}
292
293	root	1.8	/*****************************************************************************/
294
295	root	1.9	static struct ev_idle **idles;
296			static int idlemax, idlecnt;
297
298			static struct ev_check **checks;
299			static int checkmax, checkcnt;
300
301			/*****************************************************************************/
302
303	root	1.1	#if HAVE_EPOLL
304			# include "ev_epoll.c"
305			#endif
306			#if HAVE_SELECT
307			# include "ev_select.c"
308			#endif
309
310			int ev_init (int flags)
311			{
312			#if HAVE_MONOTONIC
313			{
314			struct timespec ts;
315			if (!clock_gettime (CLOCK_MONOTONIC, &ts))
316			have_monotonic = 1;
317			}
318			#endif
319
320			ev_now = ev_time ();
321	root	1.4	now = get_clock ();
322			diff = ev_now - now;
323	root	1.1
324	root	1.7	if (pipe (sigpipe))
325			return 0;
326
327			ev_method = EVMETHOD_NONE;
328	root	1.1	#if HAVE_EPOLL
329	root	1.7	if (ev_method == EVMETHOD_NONE) epoll_init (flags);
330	root	1.1	#endif
331			#if HAVE_SELECT
332	root	1.7	if (ev_method == EVMETHOD_NONE) select_init (flags);
333	root	1.1	#endif
334
335	root	1.7	if (ev_method)
336			{
337	root	1.12	evw_init (&sigev, sigcb);
338	root	1.7	siginit ();
339			}
340
341	root	1.1	return ev_method;
342			}
343
344	root	1.8	/*****************************************************************************/
345
346	root	1.1	void ev_prefork (void)
347			{
348	root	1.11	/* nop */
349	root	1.1	}
350
351			void ev_postfork_parent (void)
352			{
353	root	1.11	/* nop */
354	root	1.1	}
355
356			void ev_postfork_child (void)
357			{
358			#if HAVE_EPOLL
359	root	1.5	if (ev_method == EVMETHOD_EPOLL)
360			epoll_postfork_child ();
361	root	1.1	#endif
362	root	1.7
363			evio_stop (&sigev);
364			close (sigpipe [0]);
365			close (sigpipe [1]);
366			pipe (sigpipe);
367			siginit ();
368	root	1.1	}
369
370	root	1.8	/*****************************************************************************/
371
372	root	1.1	static void
373	root	1.5	fd_reify (void)
374			{
375			int i;
376
377			for (i = 0; i < fdchangecnt; ++i)
378			{
379			int fd = fdchanges [i];
380			ANFD *anfd = anfds + fd;
381			struct ev_io *w;
382
383			int wev = 0;
384
385			for (w = anfd->head; w; w = w->next)
386			wev \|= w->events;
387
388			if (anfd->wev != wev)
389			{
390			method_modify (fd, anfd->wev, wev);
391			anfd->wev = wev;
392			}
393			}
394
395			fdchangecnt = 0;
396			}
397
398			static void
399	root	1.1	call_pending ()
400			{
401			int i;
402
403			for (i = 0; i < pendingcnt; ++i)
404			{
405			ANPENDING *p = pendings + i;
406
407			if (p->w)
408			{
409			p->w->pending = 0;
410			p->w->cb (p->w, p->events);
411			}
412			}
413
414			pendingcnt = 0;
415			}
416
417			static void
418	root	1.12	timers_reify ()
419	root	1.1	{
420	root	1.4	while (timercnt && timers [0]->at <= now)
421	root	1.1	{
422			struct ev_timer *w = timers [0];
423
424	root	1.4	/* first reschedule or stop timer */
425	root	1.1	if (w->repeat)
426			{
427	root	1.12	w->at = now + w->repeat;
428			assert (("timer timeout in the past, negative repeat?", w->at > now));
429			downheap ((WT *)timers, timercnt, 0);
430			}
431			else
432			evtimer_stop (w); /* nonrepeating: stop timer */
433
434			event ((W)w, EV_TIMEOUT);
435			}
436			}
437	root	1.4
438	root	1.12	static void
439			periodics_reify ()
440			{
441			while (periodiccnt && periodics [0]->at <= ev_now)
442			{
443			struct ev_periodic *w = periodics [0];
444	root	1.1
445	root	1.12	/* first reschedule or stop timer */
446			if (w->interval)
447			{
448			w->at += floor ((ev_now - w->at) / w->interval + 1.) * w->interval;
449			assert (("periodic timeout in the past, negative interval?", w->at > ev_now));
450			downheap ((WT *)periodics, periodiccnt, 0);
451	root	1.1	}
452			else
453	root	1.12	evperiodic_stop (w); /* nonrepeating: stop timer */
454
455			event ((W)w, EV_TIMEOUT);
456			}
457			}
458
459			static void
460			time_jump (ev_tstamp diff)
461			{
462			int i;
463
464			/* adjust periodics */
465			for (i = 0; i < periodiccnt; ++i)
466			{
467			struct ev_periodic *w = periodics [i];
468
469			if (w->interval)
470	root	1.4	{
471	root	1.12	ev_tstamp diff = ceil ((ev_now - w->at) / w->interval) * w->interval;
472
473			if (fabs (diff) >= 1e-4)
474			{
475			evperiodic_stop (w);
476			evperiodic_start (w);
477
478			i = 0; /* restart loop, inefficient, but time jumps should be rare */
479			}
480	root	1.4	}
481	root	1.12	}
482	root	1.1
483	root	1.12	/* adjust timers. this is easy, as the offset is the same for all */
484			for (i = 0; i < timercnt; ++i)
485			timers [i]->at += diff;
486	root	1.1	}
487
488	root	1.4	static void
489			time_update ()
490			{
491			int i;
492	root	1.12
493	root	1.4	ev_now = ev_time ();
494
495			if (have_monotonic)
496			{
497			ev_tstamp odiff = diff;
498
499	root	1.12	for (i = 4; --i; ) /* loop a few times, before making important decisions */
500	root	1.4	{
501			now = get_clock ();
502			diff = ev_now - now;
503
504			if (fabs (odiff - diff) < MIN_TIMEJUMP)
505			return; /* all is well */
506
507			ev_now = ev_time ();
508			}
509
510	root	1.12	time_jump (diff - odiff);
511	root	1.4	}
512			else
513			{
514			if (now > ev_now \|\| now < ev_now - MAX_BLOCKTIME - MIN_TIMEJUMP)
515	root	1.12	time_jump (ev_now - now);
516	root	1.4
517			now = ev_now;
518			}
519			}
520
521	root	1.1	int ev_loop_done;
522
523	root	1.4	void ev_loop (int flags)
524	root	1.1	{
525			double block;
526			ev_loop_done = flags & EVLOOP_ONESHOT;
527
528	root	1.9	if (checkcnt)
529			{
530	root	1.10	queue_events ((W *)checks, checkcnt, EV_CHECK);
531	root	1.9	call_pending ();
532			}
533
534	root	1.1	do
535			{
536			/* update fd-related kernel structures */
537	root	1.5	fd_reify ();
538	root	1.1
539			/* calculate blocking time */
540	root	1.12
541			/* we only need this for !monotonic clock, but as we always have timers, we just calculate it every time */
542			ev_now = ev_time ();
543
544	root	1.9	if (flags & EVLOOP_NONBLOCK \|\| idlecnt)
545	root	1.1	block = 0.;
546			else
547			{
548	root	1.4	block = MAX_BLOCKTIME;
549
550	root	1.12	if (timercnt)
551	root	1.4	{
552	root	1.12	ev_tstamp to = timers [0]->at - get_clock () + method_fudge;
553	root	1.4	if (block > to) block = to;
554			}
555
556	root	1.12	if (periodiccnt)
557	root	1.4	{
558	root	1.12	ev_tstamp to = periodics [0]->at - ev_now + method_fudge;
559	root	1.4	if (block > to) block = to;
560			}
561
562	root	1.1	if (block < 0.) block = 0.;
563			}
564
565			method_poll (block);
566
567	root	1.4	/* update ev_now, do magic */
568			time_update ();
569
570	root	1.9	/* queue pending timers and reschedule them */
571	root	1.12	periodics_reify (); /* absolute timers first */
572			timers_reify (); /* relative timers second */
573	root	1.1
574	root	1.9	/* queue idle watchers unless io or timers are pending */
575			if (!pendingcnt)
576	root	1.10	queue_events ((W *)idles, idlecnt, EV_IDLE);
577	root	1.9
578			/* queue check and possibly idle watchers */
579	root	1.10	queue_events ((W *)checks, checkcnt, EV_CHECK);
580	root	1.9
581	root	1.1	call_pending ();
582			}
583			while (!ev_loop_done);
584			}
585
586	root	1.8	/*****************************************************************************/
587
588	root	1.1	static void
589	root	1.10	wlist_add (WL *head, WL elem)
590	root	1.1	{
591			elem->next = *head;
592			*head = elem;
593			}
594
595			static void
596	root	1.10	wlist_del (WL *head, WL elem)
597	root	1.1	{
598			while (*head)
599			{
600			if (*head == elem)
601			{
602			*head = elem->next;
603			return;
604			}
605
606			head = &(*head)->next;
607			}
608			}
609
610			static void
611	root	1.10	ev_start (W w, int active)
612	root	1.1	{
613			w->pending = 0;
614			w->active = active;
615			}
616
617			static void
618	root	1.10	ev_stop (W w)
619	root	1.1	{
620			if (w->pending)
621			pendings [w->pending - 1].w = 0;
622
623			w->active = 0;
624			}
625
626	root	1.8	/*****************************************************************************/
627
628	root	1.1	void
629			evio_start (struct ev_io *w)
630			{
631			if (ev_is_active (w))
632			return;
633
634			int fd = w->fd;
635
636	root	1.10	ev_start ((W)w, 1);
637	root	1.1	array_needsize (anfds, anfdmax, fd + 1, anfds_init);
638	root	1.10	wlist_add ((WL *)&anfds[fd].head, (WL)w);
639	root	1.1
640			++fdchangecnt;
641			array_needsize (fdchanges, fdchangemax, fdchangecnt, );
642			fdchanges [fdchangecnt - 1] = fd;
643			}
644
645			void
646			evio_stop (struct ev_io *w)
647			{
648			if (!ev_is_active (w))
649			return;
650
651	root	1.10	wlist_del ((WL *)&anfds[w->fd].head, (WL)w);
652			ev_stop ((W)w);
653	root	1.1
654			++fdchangecnt;
655			array_needsize (fdchanges, fdchangemax, fdchangecnt, );
656			fdchanges [fdchangecnt - 1] = w->fd;
657			}
658
659	root	1.12
660	root	1.1	void
661			evtimer_start (struct ev_timer *w)
662			{
663			if (ev_is_active (w))
664			return;
665
666	root	1.12	w->at += now;
667
668			ev_start ((W)w, ++timercnt);
669			array_needsize (timers, timermax, timercnt, );
670			timers [timercnt - 1] = w;
671			upheap ((WT *)timers, timercnt - 1);
672			}
673
674			void
675			evtimer_stop (struct ev_timer *w)
676			{
677			if (!ev_is_active (w))
678			return;
679
680			if (w->active < timercnt--)
681	root	1.1	{
682	root	1.12	timers [w->active - 1] = timers [timercnt];
683			downheap ((WT *)timers, timercnt, w->active - 1);
684			}
685	root	1.4
686	root	1.12	ev_stop ((W)w);
687			}
688	root	1.4
689	root	1.12	void
690			evperiodic_start (struct ev_periodic *w)
691			{
692			if (ev_is_active (w))
693			return;
694	root	1.1
695	root	1.12	/* this formula differs from the one in periodic_reify because we do not always round up */
696			if (w->interval)
697			w->at += ceil ((ev_now - w->at) / w->interval) * w->interval;
698
699			ev_start ((W)w, ++periodiccnt);
700			array_needsize (periodics, periodicmax, periodiccnt, );
701			periodics [periodiccnt - 1] = w;
702			upheap ((WT *)periodics, periodiccnt - 1);
703	root	1.1	}
704
705			void
706	root	1.12	evperiodic_stop (struct ev_periodic *w)
707	root	1.1	{
708			if (!ev_is_active (w))
709			return;
710
711	root	1.12	if (w->active < periodiccnt--)
712	root	1.2	{
713	root	1.12	periodics [w->active - 1] = periodics [periodiccnt];
714			downheap ((WT *)periodics, periodiccnt, w->active - 1);
715	root	1.2	}
716
717	root	1.10	ev_stop ((W)w);
718	root	1.1	}
719
720			void
721			evsignal_start (struct ev_signal *w)
722			{
723			if (ev_is_active (w))
724			return;
725
726	root	1.10	ev_start ((W)w, 1);
727	root	1.1	array_needsize (signals, signalmax, w->signum, signals_init);
728	root	1.10	wlist_add ((WL *)&signals [w->signum - 1].head, (WL)w);
729	root	1.7
730			if (!w->next)
731			{
732			struct sigaction sa;
733			sa.sa_handler = sighandler;
734			sigfillset (&sa.sa_mask);
735			sa.sa_flags = 0;
736			sigaction (w->signum, &sa, 0);
737			}
738	root	1.1	}
739
740			void
741			evsignal_stop (struct ev_signal *w)
742			{
743			if (!ev_is_active (w))
744			return;
745
746	root	1.10	wlist_del ((WL *)&signals [w->signum - 1].head, (WL)w);
747			ev_stop ((W)w);
748	root	1.7
749			if (!signals [w->signum - 1].head)
750			signal (w->signum, SIG_DFL);
751	root	1.1	}
752
753	root	1.9	void evidle_start (struct ev_idle *w)
754			{
755			if (ev_is_active (w))
756			return;
757
758	root	1.10	ev_start ((W)w, ++idlecnt);
759	root	1.9	array_needsize (idles, idlemax, idlecnt, );
760			idles [idlecnt - 1] = w;
761			}
762
763			void evidle_stop (struct ev_idle *w)
764			{
765			idles [w->active - 1] = idles [--idlecnt];
766	root	1.10	ev_stop ((W)w);
767	root	1.9	}
768
769			void evcheck_start (struct ev_check *w)
770			{
771			if (ev_is_active (w))
772			return;
773
774	root	1.10	ev_start ((W)w, ++checkcnt);
775	root	1.9	array_needsize (checks, checkmax, checkcnt, );
776			checks [checkcnt - 1] = w;
777			}
778
779			void evcheck_stop (struct ev_check *w)
780			{
781			checks [w->active - 1] = checks [--checkcnt];
782	root	1.10	ev_stop ((W)w);
783	root	1.9	}
784
785	root	1.1	/*****************************************************************************/
786	root	1.10
787	root	1.12	#if 1
788
789			struct ev_io wio;
790	root	1.1
791			static void
792			sin_cb (struct ev_io *w, int revents)
793			{
794			fprintf (stderr, "sin %d, revents %d\n", w->fd, revents);
795			}
796
797			static void
798			ocb (struct ev_timer *w, int revents)
799			{
800	root	1.4	//fprintf (stderr, "timer %f,%f (%x) (%f) d%p\n", w->at, w->repeat, revents, w->at - ev_time (), w->data);
801			evtimer_stop (w);
802			evtimer_start (w);
803	root	1.1	}
804
805	root	1.7	static void
806			scb (struct ev_signal *w, int revents)
807			{
808			fprintf (stderr, "signal %x,%d\n", revents, w->signum);
809	root	1.12	evio_stop (&wio);
810			evio_start (&wio);
811	root	1.7	}
812
813	root	1.9	static void
814			gcb (struct ev_signal *w, int revents)
815			{
816			fprintf (stderr, "generic %x\n", revents);
817	root	1.12
818	root	1.9	}
819
820	root	1.1	int main (void)
821			{
822			ev_init (0);
823
824	root	1.12	evio_init (&wio, sin_cb, 0, EV_READ);
825			evio_start (&wio);
826	root	1.1
827	root	1.4	struct ev_timer t[10000];
828	root	1.2
829	root	1.9	#if 0
830	root	1.2	int i;
831	root	1.4	for (i = 0; i < 10000; ++i)
832	root	1.2	{
833			struct ev_timer *w = t + i;
834			evw_init (w, ocb, i);
835	root	1.12	evtimer_init_abs (w, ocb, drand48 (), 0.99775533);
836	root	1.2	evtimer_start (w);
837			if (drand48 () < 0.5)
838			evtimer_stop (w);
839			}
840	root	1.4	#endif
841
842			struct ev_timer t1;
843	root	1.12	evtimer_init (&t1, ocb, 5, 10);
844	root	1.4	evtimer_start (&t1);
845	root	1.1
846	root	1.7	struct ev_signal sig;
847	root	1.12	evsignal_init (&sig, scb, SIGQUIT);
848	root	1.7	evsignal_start (&sig);
849
850	root	1.9	struct ev_check cw;
851	root	1.12	evcheck_init (&cw, gcb);
852	root	1.9	evcheck_start (&cw);
853
854			struct ev_idle iw;
855	root	1.12	evidle_init (&iw, gcb);
856	root	1.9	evidle_start (&iw);
857
858	root	1.1	ev_loop (0);
859
860			return 0;
861			}
862
863			#endif
864
865
866
867