/* * libev poll fd activity backend * * Copyright (c) 2007 Marc Alexander Lehmann <libev@schmorp.de> * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions are * met: * * * Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * * * 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 COPYRIGHT HOLDERS AND CONTRIBUTORS * "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 COPYRIGHT * OWNER OR CONTRIBUTORS 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 <poll.h> static void pollidx_init (int *base, int count) { 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, pollidx_init); idx = pollidxs [fd]; if (idx < 0) /* need to allocate a new pollfd */ { pollidxs [fd] = idx = pollcnt++; array_needsize (struct pollfd, polls, pollmax, pollcnt, EMPTY2); 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 (idx < --pollcnt) { polls [idx] = polls [pollcnt]; pollidxs [polls [idx].fd] = idx; } } } static void poll_poll (EV_P_ ev_tstamp timeout) { int i; int res = poll (polls, pollcnt, (int)ceil (timeout * 1000.)); if (res < 0) { if (errno == EBADF) fd_ebadf (EV_A); else if (errno == ENOMEM && !syserr_cb) fd_enomem (EV_A); else if (errno != EINTR) syserr ("(libev) poll"); return; } for (i = 0; i < pollcnt; ++i) if (polls [i].revents & POLLNVAL) fd_kill (EV_A_ polls [i].fd); else fd_event ( EV_A_ polls [i].fd, (polls [i].revents & (POLLOUT | POLLERR | POLLHUP) ? EV_WRITE : 0) | (polls [i].revents & (POLLIN | POLLERR | POLLHUP) ? EV_READ : 0) ); } int inline_size poll_init (EV_P_ int flags) { backend_fudge = 1e-3; /* needed to compensate for select returning early, very conservative */ backend_modify = poll_modify; backend_poll = poll_poll; pollidxs = 0; pollidxmax = 0; polls = 0; pollmax = 0; pollcnt = 0; return EVBACKEND_POLL; } void inline_size poll_destroy (EV_P) { ev_free (pollidxs); ev_free (polls); }