text: /*
   * libevent compatibility layer
   *
   * Copyright (c) 2007,2008,2009,2010,2012 Marc Alexander Lehmann <libev@schmorp.de>
   * All rights reserved.
   *
   * Redistribution and use in source and binary forms, with or without modifica-
   * tion, are permitted provided that the following conditions are met:
   *
   *   1.  Redistributions of source code must retain the above copyright notice,
   *       this list of conditions and the following disclaimer.
   *
   *   2.  Redistributions in binary form must reproduce the above copyright
   *       notice, this list of conditions and the following disclaimer in the
   *       documentation and/or other materials provided with the distribution.
   *
   * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
   * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MER-
   * CHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO
   * EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPE-
   * CIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
   * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
   * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
   * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTH-
   * ERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
   * OF THE POSSIBILITY OF SUCH DAMAGE.
   *
   * Alternatively, the contents of this file may be used under the terms of
   * the GNU General Public License ("GPL") version 2 or any later version,
   * in which case the provisions of the GPL are applicable instead of
   * the above. If you wish to allow the use of your version of this file
   * only under the terms of the GPL and not to allow others to use your
   * version of this file under the BSD license, indicate your decision
   * by deleting the provisions above and replace them with the notice
   * and other provisions required by the GPL. If you do not delete the
   * provisions above, a recipient may use your version of this file under
   * either the BSD or the GPL.
   */
  
  #include <stddef.h>
  #include <stdlib.h>
  #include <assert.h>
  
  #ifdef EV_EVENT_H
  # include EV_EVENT_H
  #else
  # include "event.h"
  #endif
  
  #if EV_MULTIPLICITY
  # define dLOOPev struct ev_loop *loop = (struct ev_loop *)ev->ev_base
  # define dLOOPbase struct ev_loop *loop = (struct ev_loop *)base
  #else
  # define dLOOPev
  # define dLOOPbase
  #endif
  
  /* never accessed, will always be cast from/to ev_loop */
  struct event_base
  {
    int dummy;
  };
  
  static struct event_base *ev_x_cur;
  
  static ev_tstamp
  ev_tv_get (struct timeval *tv)
  {
    if (tv)
      {
        ev_tstamp after = tv->tv_sec + tv->tv_usec * 1e-6;
        return after ? after : 1e-6;
      }
    else
      return -1.;
  }
  
  #define EVENT_STRINGIFY(s) # s
  #define EVENT_VERSION(a,b) EVENT_STRINGIFY (a) "." EVENT_STRINGIFY (b)
  
  const char *
  event_get_version (void)
  {
    /* returns ABI, not API or library, version */
    return EVENT_VERSION (EV_VERSION_MAJOR, EV_VERSION_MINOR);
  }
  
  const char *
  event_get_method (void)
  {
    return "libev";
  }
  
  void *event_init (void)
  {
  #if EV_MULTIPLICITY
    if (ev_x_cur)
      ev_x_cur = (struct event_base *)ev_loop_new (EVFLAG_AUTO);
    else
      ev_x_cur = (struct event_base *)ev_default_loop (EVFLAG_AUTO);
  #else
    assert (("libev: multiple event bases not supported when not compiled with EV_MULTIPLICITY", !ev_x_cur));
  
    ev_x_cur = (struct event_base *)(long)ev_default_loop (EVFLAG_AUTO);
  #endif
  
    return ev_x_cur;
  }
  
  const char *
  event_base_get_method (const struct event_base *base)
  {
    return "libev";
  }
  
  struct event_base *
  event_base_new (void)
  {
  #if EV_MULTIPLICITY
    return (struct event_base *)ev_loop_new (EVFLAG_AUTO);
  #else
    assert (("libev: multiple event bases not supported when not compiled with EV_MULTIPLICITY"));
    return NULL;
  #endif
  }
  
  void event_base_free (struct event_base *base)
  {
    dLOOPbase;
  
  #if EV_MULTIPLICITY
    if (!ev_is_default_loop (loop))
      ev_loop_destroy (loop);
  #endif
  }
  
  int event_dispatch (void)
  {
    return event_base_dispatch (ev_x_cur);
  }
  
  #ifdef EV_STANDALONE
  void event_set_log_callback (event_log_cb cb)
  {
    /* nop */
  }
  #endif
  
  int event_loop (int flags)
  {
    return event_base_loop (ev_x_cur, flags);
  }
  
  int event_loopexit (struct timeval *tv)
  {
    return event_base_loopexit (ev_x_cur, tv);
  }
  
  event_callback_fn event_get_callback
  (const struct event *ev)
  {
    return ev->ev_callback;
  }
  
  static void
  ev_x_cb (struct event *ev, int revents)
  {
    revents &= EV_READ | EV_WRITE | EV_TIMER | EV_SIGNAL;
  
    ev->ev_res = revents;
    ev->ev_callback (ev->ev_fd, (short)revents, ev->ev_arg);
  }
  
  static void
  ev_x_cb_sig (EV_P_ struct ev_signal *w, int revents)
  {
    struct event *ev = (struct event *)(((char *)w) - offsetof (struct event, iosig.sig));
  
    if (revents & EV_ERROR)
      event_del (ev);
  
    ev_x_cb (ev, revents);
  }
  
  static void
  ev_x_cb_io (EV_P_ struct ev_io *w, int revents)
  {
    struct event *ev = (struct event *)(((char *)w) - offsetof (struct event, iosig.io));
  
    if ((revents & EV_ERROR) || !(ev->ev_events & EV_PERSIST))
      event_del (ev);
  
    ev_x_cb (ev, revents);
  }
  
  static void
  ev_x_cb_to (EV_P_ struct ev_timer *w, int revents)
  {
    struct event *ev = (struct event *)(((char *)w) - offsetof (struct event, to));
  
    event_del (ev);
  
    ev_x_cb (ev, revents);
  }
  
  void event_set (struct event *ev, int fd, short events, void (*cb)(int, short, void *), void *arg)
  {
    if (events & EV_SIGNAL)
      ev_init (&ev->iosig.sig, ev_x_cb_sig);
    else
      ev_init (&ev->iosig.io, ev_x_cb_io);
  
    ev_init (&ev->to, ev_x_cb_to);
  
    ev->ev_base     = ev_x_cur; /* not threadsafe, but it's how libevent works */
    ev->ev_fd       = fd;
    ev->ev_events   = events;
    ev->ev_pri      = 0;
    ev->ev_callback = cb;
    ev->ev_arg      = arg;
    ev->ev_res      = 0;
    ev->ev_flags    = EVLIST_INIT;
  }
  
  int event_once (int fd, short events, void (*cb)(int, short, void *), void *arg, struct timeval *tv)
  {
    return event_base_once (ev_x_cur, fd, events, cb, arg, tv);
  }
  
  int event_add (struct event *ev, struct timeval *tv)
  {
    dLOOPev;
  
    if (ev->ev_events & EV_SIGNAL)
      {
        if (!ev_is_active (&ev->iosig.sig))
          {
            ev_signal_set (&ev->iosig.sig, ev->ev_fd);
            ev_signal_start (EV_A_ &ev->iosig.sig);
  
            ev->ev_flags |= EVLIST_SIGNAL;
          }
      }
    else if (ev->ev_events & (EV_READ | EV_WRITE))
      {
        if (!ev_is_active (&ev->iosig.io))
          {
            ev_io_set (&ev->iosig.io, ev->ev_fd, ev->ev_events & (EV_READ | EV_WRITE));
            ev_io_start (EV_A_ &ev->iosig.io);
  
            ev->ev_flags |= EVLIST_INSERTED;
          }
      }
  
    if (tv)
      {
        ev->to.repeat = ev_tv_get (tv);
        ev_timer_again (EV_A_ &ev->to);
        ev->ev_flags |= EVLIST_TIMEOUT;
      }
    else
      {
        ev_timer_stop (EV_A_ &ev->to);
        ev->ev_flags &= ~EVLIST_TIMEOUT;
      }
  
    ev->ev_flags |= EVLIST_ACTIVE;
  
    return 0;
  }
  
  int event_del (struct event *ev)
  {
    dLOOPev;
  
    if (ev->ev_events & EV_SIGNAL)
      ev_signal_stop (EV_A_ &ev->iosig.sig);
    else if (ev->ev_events & (EV_READ | EV_WRITE))
      ev_io_stop (EV_A_ &ev->iosig.io);
  
    if (ev_is_active (&ev->to))
      ev_timer_stop (EV_A_ &ev->to);
  
    ev->ev_flags = EVLIST_INIT;
  
    return 0;
  }
  
  void event_active (struct event *ev, int res, short ncalls)
  {
    dLOOPev;
  
    if (res & EV_TIMEOUT)
      ev_feed_event (EV_A_ &ev->to, res & EV_TIMEOUT);
  
    if (res & EV_SIGNAL)
      ev_feed_event (EV_A_ &ev->iosig.sig, res & EV_SIGNAL);
  
    if (res & (EV_READ | EV_WRITE))
      ev_feed_event (EV_A_ &ev->iosig.io, res & (EV_READ | EV_WRITE));
  }
  
  int event_pending (struct event *ev, short events, struct timeval *tv)
  {
    short revents = 0;
    dLOOPev;
  
    if (ev->ev_events & EV_SIGNAL)
      {
        /* sig */
        if (ev_is_active (&ev->iosig.sig) || ev_is_pending (&ev->iosig.sig))
          revents |= EV_SIGNAL;
      }
    else if (ev->ev_events & (EV_READ | EV_WRITE))
      {
        /* io */
        if (ev_is_active (&ev->iosig.io) || ev_is_pending (&ev->iosig.io))
          revents |= ev->ev_events & (EV_READ | EV_WRITE);
      }
  
    if (ev->ev_events & EV_TIMEOUT || ev_is_active (&ev->to) || ev_is_pending (&ev->to))
      {
        revents |= EV_TIMEOUT;
  
        if (tv)
          {
            ev_tstamp at = ev_now (EV_A);
  
            tv->tv_sec  = (long)at;
            tv->tv_usec = (long)((at - (ev_tstamp)tv->tv_sec) * 1e6);
          }
      }
  
    return events & revents;
  }
  
  int event_priority_init (int npri)
  {
    return event_base_priority_init (ev_x_cur, npri);
  }
  
  int event_priority_set (struct event *ev, int pri)
  {
    ev->ev_pri = pri;
  
    return 0;
  }
  
  int event_base_set (struct event_base *base, struct event *ev)
  {
    ev->ev_base = base;
  
    return 0;
  }
  
  int event_base_loop (struct event_base *base, int flags)
  {
    dLOOPbase;
  
    return !ev_run (EV_A_ flags);
  }
  
  int event_base_dispatch (struct event_base *base)
  {
    return event_base_loop (base, 0);
  }
  
  static void
  ev_x_loopexit_cb (int revents, void *base)
  {
    dLOOPbase;
  
    ev_break (EV_A_ EVBREAK_ONE);
  }
  
  int event_base_loopexit (struct event_base *base, struct timeval *tv)
  {
    ev_tstamp after = ev_tv_get (tv);
    dLOOPbase;
  
    ev_once (EV_A_ -1, 0, after >= 0. ? after : 0., ev_x_loopexit_cb, (void *)base);
  
    return 0;
  }
  
  struct ev_x_once
  {
    int fd;
    void (*cb)(int, short, void *);
    void *arg;
  };
  
  static void
  ev_x_once_cb (int revents, void *arg)
  {
    struct ev_x_once *once = (struct ev_x_once *)arg;
  
    once->cb (once->fd, (short)revents, once->arg);
    free (once);
  }
  
  int event_base_once (struct event_base *base, int fd, short events, void (*cb)(int, short, void *), void *arg, struct timeval *tv)
  {
    struct ev_x_once *once = (struct ev_x_once *)malloc (sizeof (struct ev_x_once));
    dLOOPbase;
  
    if (!once)
      return -1;
  
    once->fd  = fd;
    once->cb  = cb;
    once->arg = arg;
  
    ev_once (EV_A_ fd, events & (EV_READ | EV_WRITE), ev_tv_get (tv), ev_x_once_cb, (void *)once);
  
    return 0;
  }
  
  int event_base_priority_init (struct event_base *base, int npri)
  {
    /*dLOOPbase;*/
  
    return 0;
  }
  
  