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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 <sys/epoll.h> |
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|
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static void |
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epoll_modify (EV_P_ int fd, int oev, int nev) |
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{ |
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int mode = nev ? oev ? EPOLL_CTL_MOD : EPOLL_CTL_ADD : EPOLL_CTL_DEL; |
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|
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struct epoll_event ev; |
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ev.data.u64 = fd; /* use u64 to fully initialise the struct, for nicer strace etc. */ |
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ev.events = |
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(nev & EV_READ ? EPOLLIN : 0) |
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| (nev & EV_WRITE ? EPOLLOUT : 0); |
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|
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epoll_ctl (epoll_fd, mode, fd, &ev); |
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} |
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|
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static void |
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epoll_postfork_child (EV_P) |
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{ |
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int fd; |
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|
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epoll_fd = epoll_create (256); |
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fcntl (epoll_fd, F_SETFD, FD_CLOEXEC); |
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|
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/* re-register interest in fds */ |
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for (fd = 0; fd < anfdmax; ++fd) |
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if (anfds [fd].events)//D |
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epoll_modify (EV_A_ fd, EV_NONE, anfds [fd].events); |
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} |
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|
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static void |
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epoll_poll (EV_P_ ev_tstamp timeout) |
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{ |
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int eventcnt = epoll_wait (epoll_fd, events, eventmax, ceil (timeout * 1000.)); |
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int i; |
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|
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if (eventcnt < 0) |
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return; |
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|
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for (i = 0; i < eventcnt; ++i) |
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fd_event ( |
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EV_A_ |
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events [i].data.u64, |
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(events [i].events & (EPOLLOUT | EPOLLERR | EPOLLHUP) ? EV_WRITE : 0) |
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| (events [i].events & (EPOLLIN | EPOLLERR | EPOLLHUP) ? EV_READ : 0) |
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); |
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|
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/* if the receive array was full, increase its size */ |
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if (expect_false (eventcnt == eventmax)) |
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{ |
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free (events); |
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eventmax = array_roundsize (events, eventmax << 1); |
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events = malloc (sizeof (struct epoll_event) * eventmax); |
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} |
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} |
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|
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static int |
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epoll_init (EV_P_ int flags) |
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{ |
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epoll_fd = epoll_create (256); |
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|
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if (epoll_fd < 0) |
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return 0; |
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|
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fcntl (epoll_fd, F_SETFD, FD_CLOEXEC); |
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|
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method_fudge = 1e-3; /* needed to compensate for epoll returning early */ |
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method_modify = epoll_modify; |
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method_poll = epoll_poll; |
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|
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eventmax = 64; /* intiial number of events receivable per poll */ |
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events = malloc (sizeof (struct epoll_event) * eventmax); |
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|
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return EVMETHOD_EPOLL; |
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} |
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|
