JezK
Edit File: ev_poll.c
/* * libev poll fd activity backend * * Copyright (c) 2007,2008,2009,2010,2011,2016,2019 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 <poll.h> inline_size void array_needsize_pollidx (int *base, int offset, int count) { /* using memset (.., -1, ...) is tempting, we we try * to be ultraportable */ base += offset; while (count--) *base++ = -1; } static void poll_modify (EV_P_ int fd, int oev, int nev) { int idx; if (oev == nev) return; array_needsize (int, pollidxs, pollidxmax, fd + 1, array_needsize_pollidx); idx = pollidxs [fd]; if (idx < 0) /* need to allocate a new pollfd */ { pollidxs [fd] = idx = pollcnt++; array_needsize (struct pollfd, polls, pollmax, pollcnt, array_needsize_noinit); polls [idx].fd = fd; } assert (polls [idx].fd == fd); if (nev) polls [idx].events = (nev & EV_READ ? POLLIN : 0) | (nev & EV_WRITE ? POLLOUT : 0); else /* remove pollfd */ { pollidxs [fd] = -1; if (ecb_expect_true (idx < --pollcnt)) { polls [idx] = polls [pollcnt]; pollidxs [polls [idx].fd] = idx; } } } static void poll_poll (EV_P_ ev_tstamp timeout) { struct pollfd *p; int res; EV_RELEASE_CB; res = poll (polls, pollcnt, EV_TS_TO_MSEC (timeout)); EV_ACQUIRE_CB; if (ecb_expect_false (res < 0)) { if (errno == EBADF) fd_ebadf (EV_A); else if (errno == ENOMEM && !syserr_cb) fd_enomem (EV_A); else if (errno != EINTR) ev_syserr ("(libev) poll"); } else for (p = polls; res; ++p) { assert (("libev: poll returned illegal result, broken BSD kernel?", p < polls + pollcnt)); if (ecb_expect_false (p->revents)) /* this expect is debatable */ { --res; if (ecb_expect_false (p->revents & POLLNVAL)) { assert (("libev: poll found invalid fd in poll set", 0)); fd_kill (EV_A_ p->fd); } else fd_event ( EV_A_ p->fd, (p->revents & (POLLOUT | POLLERR | POLLHUP) ? EV_WRITE : 0) | (p->revents & (POLLIN | POLLERR | POLLHUP) ? EV_READ : 0) ); } } } inline_size int poll_init (EV_P_ int flags) { backend_mintime = EV_TS_CONST (1e-3); backend_modify = poll_modify; backend_poll = poll_poll; pollidxs = 0; pollidxmax = 0; polls = 0; pollmax = 0; pollcnt = 0; return EVBACKEND_POLL; } inline_size void poll_destroy (EV_P) { ev_free (pollidxs); ev_free (polls); }