/* * Copyright 2007 Marc Alexander Lehmann <libev@schmorp.de> * Copyright 2000-2002 Niels Provos <provos@citi.umich.edu> * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, 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. * 3. The name of the author may not be used to endorse or promote products * derived from this software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, * INCIDENTAL, SPECIAL, 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 OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ #include <sys/types.h> #include <sys/time.h> #include <sys/queue.h> #include <sys/event.h> #include <string.h> #include <errno.h> static int kq_fd; static struct kevent *kq_changes; static int kq_changemax, kq_changecnt; static struct kevent *kq_events; static int kq_eventmax; static void kqueue_change (int fd, int filter, int flags, int fflags) { struct kevent *ke; array_needsize (kq_changes, kq_changemax, ++kq_changecnt, ); ke = &kq_changes [kq_changecnt - 1]; memset (ke, 0, sizeof (struct kevent)); ke->ident = fd; ke->filter = filter; ke->flags = flags; ke->fflags = fflags; } static void kqueue_modify (int fd, int oev, int nev) { if ((oev ^ new) & EV_READ) { if (nev & EV_READ) kqueue_change (fd, EVFILT_READ, EV_ADD, NOTE_EOF); else kqueue_change (fd, EVFILT_READ, EV_DELETE, 0); } if ((oev ^ new) & EV_WRITE) { if (nev & EV_WRITE) kqueue_change (fd, EVFILT_WRITE, EV_ADD, NOTE_EOF); else kqueue_change (fd, EVFILT_WRITE, EV_DELETE, 0); } } static void kqueue_poll (ev_tstamp timeout) { int res, i; struct timespec ts; ts.tv_sec = (time_t)timeout; ts.tv_nsec = (long)(timeout - (ev_tstamp)ts.tv_sec) * 1e9; res = kevent (kq_fd, kq_changes, kq_changecnt, kq_events, kq_eventmax, &ts); kq_changecnt = 0; if (res < 0) return; for (i = 0; i < res; ++i) { if (kq_events [i].flags & EV_ERROR) { /* * Error messages that can happen, when a delete fails. * EBADF happens when the file discriptor has been * closed, * ENOENT when the file discriptor was closed and * then reopened. * EINVAL for some reasons not understood; EINVAL * should not be returned ever; but FreeBSD does :-\ * An error is also indicated when a callback deletes * an event we are still processing. In that case * the data field is set to ENOENT. */ if (events [i].data == EBADF) fd_kill (events [i].ident); } else fd_event ( events [i].ident, events [i].filter == EVFILT_READ ? EV_READ : events [i].filter == EVFILT_WRITE ? EV_WRITE : 0 ); } if (expect_false (res == kq_eventmax)) { free (kq_events); kq_eventmax = array_roundsize (kq_events, kq_eventmax << 1); kq_events = malloc (sizeof (struct kevent) * kq_eventmax); } } static void kqueue_init (struct event_base *base) { struct kevent ch, ev; /* Initalize the kernel queue */ if ((kq_fd = kqueue ()) < 0) return; /* Check for Mac OS X kqueue bug. */ ch.ident = -1; ch.filter = EVFILT_READ; ch.flags = EV_ADD; /* * If kqueue works, then kevent will succeed, and it will * stick an error in events[0]. If kqueue is broken, then * kevent will fail. */ if (kevent (kq_fd, &ch, 1, &ev, 1, 0) != 1 || ev.ident != -1 || ev.flags != EV_ERROR) { /* detected broken kqueue */ close (kq_fd); return; } ev_method = EVMETHOD_KQUEUE; method_fudge = 1e-3; /* needed to compensate for kevent returning early */ method_modify = kq_modify; method_poll = kq_poll; kq_eventmax = 64; /* intiial number of events receivable per poll */ kq_events = malloc (sizeof (struct kevent) * kq_eventmax); }