text: /*
   * libev solaris event port backend
   *
   * Copyright (c) 2007,2008,2009,2010,2011 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.
   */
  
  /* useful reading:
   *
   * http://bugs.opensolaris.org/view_bug.do?bug_id=6268715 (random results)
   * http://bugs.opensolaris.org/view_bug.do?bug_id=6455223 (just totally broken)
   * http://bugs.opensolaris.org/view_bug.do?bug_id=6873782 (manpage ETIME)
   * http://bugs.opensolaris.org/view_bug.do?bug_id=6874410 (implementation ETIME)
   * http://www.mail-archive.com/networking-discuss@opensolaris.org/msg11898.html ETIME vs. nget
   * http://src.opensolaris.org/source/xref/onnv/onnv-gate/usr/src/lib/libc/port/gen/event_port.c (libc)
   * http://cvs.opensolaris.org/source/xref/onnv/onnv-gate/usr/src/uts/common/fs/portfs/port.c#1325 (kernel)
   */
  
  #include <sys/types.h>
  #include <sys/time.h>
  #include <poll.h>
  #include <port.h>
  #include <string.h>
  #include <errno.h>
  
  void inline_speed
  port_associate_and_check (EV_P_ int fd, int ev)
  {
    if (0 >
        port_associate (
           backend_fd, PORT_SOURCE_FD, fd,
           (ev & EV_READ ? POLLIN : 0)
           | (ev & EV_WRITE ? POLLOUT : 0),
           0
        )
    )
      {
        if (errno == EBADFD)
          fd_kill (EV_A_ fd);
        else
          ev_syserr ("(libev) port_associate");
      }
  }
  
  static void
  port_modify (EV_P_ int fd, int oev, int nev)
  {
    /* we need to reassociate no matter what, as closes are
     * once more silently being discarded.
     */
    if (!nev)
      {
        if (oev)
          port_dissociate (backend_fd, PORT_SOURCE_FD, fd);
      }
    else
      port_associate_and_check (EV_A_ fd, nev);
  }
  
  static void
  port_poll (EV_P_ ev_tstamp timeout)
  {
    int res, i;
    struct timespec ts;
    uint_t nget = 1;
  
    /* we initialise this to something we will skip in the loop, as */
    /* port_getn can return with nget unchanged, but no indication */
    /* whether it was the original value or has been updated :/ */
    port_events [0].portev_source = 0;
  
    EV_RELEASE_CB;
    EV_TS_SET (ts, timeout);
    res = port_getn (backend_fd, port_events, port_eventmax, &nget, &ts);
    EV_ACQUIRE_CB;
  
    /* port_getn may or may not set nget on error */
    /* so we rely on port_events [0].portev_source not being updated */
    if (res == -1 && errno != ETIME && errno != EINTR)
      ev_syserr ("(libev) port_getn (see http://bugs.opensolaris.org/view_bug.do?bug_id=6268715, try LIBEV_FLAGS=3 env variable)");
  
    for (i = 0; i < nget; ++i)
      {
        if (port_events [i].portev_source == PORT_SOURCE_FD)
          {
            int fd = port_events [i].portev_object;
  
            fd_event (
              EV_A_
              fd,
              (port_events [i].portev_events & (POLLOUT | POLLERR | POLLHUP) ? EV_WRITE : 0)
              | (port_events [i].portev_events & (POLLIN | POLLERR | POLLHUP) ? EV_READ : 0)
            );
  
            fd_change (EV_A_ fd, EV__IOFDSET);
          }
      }
  
    if (expect_false (nget == port_eventmax))
      {
        ev_destroy (port_events);
        port_eventmax = array_nextsize (sizeof (port_event_t), port_eventmax, port_eventmax + 1);
        port_events = (port_event_t *)ev_malloc (sizeof (port_event_t) * port_eventmax);
      }
  }
  
  int inline_size
  port_init (EV_P_ int flags)
  {
    /* Initialize the kernel queue */
    if ((backend_fd = port_create ()) < 0)
      return 0;
  
    assert (("libev: PORT_SOURCE_FD must not be zero", PORT_SOURCE_FD));
  
    fcntl (backend_fd, F_SETFD, FD_CLOEXEC); /* not sure if necessary, hopefully doesn't hurt */
  
    /* if my reading of the opensolaris kernel sources are correct, then
     * opensolaris does something very stupid: it checks if the time has already
     * elapsed and doesn't round up if that is the case,m otherwise it DOES round
     * up. Since we can't know what the case is, we need to guess by using a
     * "large enough" timeout. Normally, 1e-9 would be correct.
     */
    backend_mintime = 1e-3; /* needed to compensate for port_getn returning early */
    backend_modify  = port_modify;
    backend_poll    = port_poll;
  
    port_eventmax = 64; /* initial number of events receivable per poll */
    port_events = (port_event_t *)ev_malloc (sizeof (port_event_t) * port_eventmax);
  
    return EVBACKEND_PORT;
  }
  
  void inline_size
  port_destroy (EV_P)
  {
    ev_destroy (port_events);
  }
  
  void inline_size
  port_fork (EV_P)
  {
    close (backend_fd);
  
    while ((backend_fd = port_create ()) < 0)
      ev_syserr ("(libev) port");
  
    fcntl (backend_fd, F_SETFD, FD_CLOEXEC);
  
    /* re-register interest in fds */
    fd_rearm_all (EV_A);
  }
  
  