JezK
Edit File: ev_port.c
/* * libev solaris event port backend * * Copyright (c) 2007,2008,2009,2010,2011,2019 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. */ /* 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> inline_speed void 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) { assert (("libev: port_associate found invalid fd", 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 (ecb_expect_false (nget == port_eventmax)) { ev_free (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); } } inline_size int 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, 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 = EV_TS_CONST (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; } inline_size void port_destroy (EV_P) { ev_free (port_events); } inline_size void 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); }