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/* |
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* libev epoll fd activity backend |
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* |
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* Copyright (c) 2007 Marc Alexander Lehmann <libev@schmorp.de> |
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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 are |
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* met: |
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* |
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* * 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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* |
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* * Redistributions in binary form must reproduce the above |
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* copyright notice, this list of conditions and the following |
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* disclaimer in the documentation and/or other materials provided |
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* with the distribution. |
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* |
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* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
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* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
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* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR |
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* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT |
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* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
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* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT |
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* 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 |
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* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
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*/ |
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|
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#include <poll.h> |
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|
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static void |
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pollidx_init (int *base, int count) |
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{ |
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while (count--) |
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*base++ = -1; |
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} |
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|
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static void |
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poll_modify (EV_P_ int fd, int oev, int nev) |
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{ |
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int idx; |
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|
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if (oev == nev) |
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return; |
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|
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array_needsize (pollidxs, pollidxmax, fd + 1, pollidx_init); |
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|
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idx = pollidxs [fd]; |
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|
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if (idx < 0) /* need to allocate a new pollfd */ |
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{ |
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idx = pollcnt++; |
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array_needsize (polls, pollmax, pollcnt, ); |
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polls [idx].fd = fd; |
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} |
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|
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if (nev) |
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polls [idx].events = |
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(nev & EV_READ ? POLLIN : 0) |
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| (nev & EV_WRITE ? POLLOUT : 0); |
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else /* remove pollfd */ |
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{ |
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if (idx < pollcnt--) |
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{ |
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pollidxs [fd] = -1; |
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polls [idx] = polls [pollcnt]; |
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pollidxs [polls [idx].fd] = idx; |
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} |
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} |
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} |
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|
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static void |
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poll_poll (EV_P_ ev_tstamp timeout) |
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{ |
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int i; |
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int res = poll (polls, pollcnt, ceil (timeout * 1000.)); |
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|
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if (res < 0) |
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{ |
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if (errno == EBADF) |
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fd_ebadf (EV_A); |
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else if (errno == ENOMEM && !syserr_cb) |
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fd_enomem (EV_A); |
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else if (errno != EINTR) |
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syserr (); |
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|
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return; |
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} |
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|
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for (i = 0; i < pollcnt; ++i) |
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fd_event ( |
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EV_A_ |
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polls [i].fd, |
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(polls [i].revents & (POLLOUT | POLLERR | POLLHUP) ? EV_WRITE : 0) |
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| (polls [i].revents & (POLLIN | POLLERR | POLLHUP) ? EV_READ : 0) |
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); |
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} |
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|
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static int |
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poll_init (EV_P_ int flags) |
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{ |
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method_fudge = 1e-3; /* needed to compensate for select returning early, very conservative */ |
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method_modify = poll_modify; |
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method_poll = poll_poll; |
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|
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pollidxs = 0; pollidxmax = 0; |
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polls = 0; pollmax = 0; pollcnt = 0; |
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|
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return EVMETHOD_POLL; |
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} |
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|
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static void |
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poll_destroy (EV_P) |
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{ |
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ev_free (pollidxs); |
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ev_free (polls); |
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} |