JezK
Edit File: ev_kqueue.c
/* * 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