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