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- /*
- * libev kqueue backend
- *
- * Copyright (c) 2007,2008,2009,2010,2011,2012,2013,2016,2019 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 <sys/types.h>
- #include <sys/time.h>
- #include <sys/event.h>
- #include <string.h>
- #include <errno.h>
-
- inline_speed
- void
- kqueue_change (EV_P_ int fd, int filter, int flags, int fflags)
- {
- ++kqueue_changecnt;
- array_needsize (struct kevent, kqueue_changes, kqueue_changemax, kqueue_changecnt, array_needsize_noinit);
-
- EV_SET (&kqueue_changes [kqueue_changecnt - 1], fd, filter, flags, fflags, 0, 0);
- }
-
- /* OS X at least needs this */
- #ifndef EV_ENABLE
- # define EV_ENABLE 0
- #endif
- #ifndef NOTE_EOF
- # define NOTE_EOF 0
- #endif
-
- static void
- kqueue_modify (EV_P_ int fd, int oev, int nev)
- {
- if (oev != nev)
- {
- if (oev & EV_READ)
- kqueue_change (EV_A_ fd, EVFILT_READ , EV_DELETE, 0);
-
- if (oev & EV_WRITE)
- kqueue_change (EV_A_ fd, EVFILT_WRITE, EV_DELETE, 0);
- }
-
- /* to detect close/reopen reliably, we have to re-add */
- /* event requests even when oev == nev */
-
- if (nev & EV_READ)
- kqueue_change (EV_A_ fd, EVFILT_READ , EV_ADD | EV_ENABLE, NOTE_EOF);
-
- if (nev & EV_WRITE)
- kqueue_change (EV_A_ fd, EVFILT_WRITE, EV_ADD | EV_ENABLE, NOTE_EOF);
- }
-
- static void
- kqueue_poll (EV_P_ ev_tstamp timeout)
- {
- int res, i;
- struct timespec ts;
-
- /* need to resize so there is enough space for errors */
- if (kqueue_changecnt > kqueue_eventmax)
- {
- ev_free (kqueue_events);
- kqueue_eventmax = array_nextsize (sizeof (struct kevent), kqueue_eventmax, kqueue_changecnt);
- kqueue_events = (struct kevent *)ev_malloc (sizeof (struct kevent) * kqueue_eventmax);
- }
-
- EV_RELEASE_CB;
- EV_TS_SET (ts, timeout);
- res = kevent (backend_fd, kqueue_changes, kqueue_changecnt, kqueue_events, kqueue_eventmax, &ts);
- EV_ACQUIRE_CB;
- kqueue_changecnt = 0;
-
- if (ecb_expect_false (res < 0))
- {
- if (errno != EINTR)
- ev_syserr ("(libev) kqueue kevent");
-
- return;
- }
-
- for (i = 0; i < res; ++i)
- {
- int fd = kqueue_events [i].ident;
-
- if (ecb_expect_false (kqueue_events [i].flags & EV_ERROR))
- {
- int err = kqueue_events [i].data;
-
- /* we are only interested in errors for fds that we are interested in :) */
- if (anfds [fd].events)
- {
- if (err == ENOENT) /* resubmit changes on ENOENT */
- kqueue_modify (EV_A_ fd, 0, anfds [fd].events);
- else if (err == EBADF) /* on EBADF, we re-check the fd */
- {
- if (fd_valid (fd))
- kqueue_modify (EV_A_ fd, 0, anfds [fd].events);
- else
- {
- assert (("libev: kqueue found invalid fd", 0));
- fd_kill (EV_A_ fd);
- }
- }
- else /* on all other errors, we error out on the fd */
- {
- assert (("libev: kqueue found invalid fd", 0));
- fd_kill (EV_A_ fd);
- }
- }
- }
- else
- fd_event (
- EV_A_
- fd,
- kqueue_events [i].filter == EVFILT_READ ? EV_READ
- : kqueue_events [i].filter == EVFILT_WRITE ? EV_WRITE
- : 0
- );
- }
-
- if (ecb_expect_false (res == kqueue_eventmax))
- {
- ev_free (kqueue_events);
- kqueue_eventmax = array_nextsize (sizeof (struct kevent), kqueue_eventmax, kqueue_eventmax + 1);
- kqueue_events = (struct kevent *)ev_malloc (sizeof (struct kevent) * kqueue_eventmax);
- }
- }
-
- inline_size
- int
- kqueue_init (EV_P_ int flags)
- {
- /* initialize the kernel queue */
- kqueue_fd_pid = getpid ();
- if ((backend_fd = kqueue ()) < 0)
- return 0;
-
- fcntl (backend_fd, F_SETFD, FD_CLOEXEC); /* not sure if necessary, hopefully doesn't hurt */
-
- backend_mintime = EV_TS_CONST (1e-9); /* apparently, they did the right thing in freebsd */
- backend_modify = kqueue_modify;
- backend_poll = kqueue_poll;
-
- kqueue_eventmax = 64; /* initial number of events receivable per poll */
- kqueue_events = (struct kevent *)ev_malloc (sizeof (struct kevent) * kqueue_eventmax);
-
- kqueue_changes = 0;
- kqueue_changemax = 0;
- kqueue_changecnt = 0;
-
- return EVBACKEND_KQUEUE;
- }
-
- inline_size
- void
- kqueue_destroy (EV_P)
- {
- ev_free (kqueue_events);
- ev_free (kqueue_changes);
- }
-
- inline_size
- void
- kqueue_fork (EV_P)
- {
- /* some BSD kernels don't just destroy the kqueue itself,
- * but also close the fd, which isn't documented, and
- * impossible to support properly.
- * we remember the pid of the kqueue call and only close
- * the fd if the pid is still the same.
- * this leaks fds on sane kernels, but BSD interfaces are
- * notoriously buggy and rarely get fixed.
- */
- pid_t newpid = getpid ();
-
- if (newpid == kqueue_fd_pid)
- close (backend_fd);
-
- kqueue_fd_pid = newpid;
- while ((backend_fd = kqueue ()) < 0)
- ev_syserr ("(libev) kqueue");
-
- fcntl (backend_fd, F_SETFD, FD_CLOEXEC);
-
- /* re-register interest in fds */
- fd_rearm_all (EV_A);
- }
-
- /* sys/event.h defines EV_ERROR */
- #undef EV_ERROR
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