/* * libev select 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. */ #ifndef _WIN32 /* for unix systems */ # include <sys/select.h> # include <inttypes.h> #endif #ifndef EV_SELECT_USE_FD_SET # ifdef NFDBITS # define EV_SELECT_USE_FD_SET 0 # else # define EV_SELECT_USE_FD_SET 1 # endif #endif #if EV_SELECT_IS_WINSOCKET # undef EV_SELECT_USE_FD_SET # define EV_SELECT_USE_FD_SET 1 # undef EINTR # define EINTR WSAEINTR # undef EBADF # define EBADF WSAENOTSOCK # undef ENOMEM # define ENOMEM (errno + 1) #endif #if !EV_SELECT_USE_FD_SET # define NFDBYTES (NFDBITS / 8) #endif #include <string.h> static void select_modify (EV_P_ int fd, int oev, int nev) { if (oev == nev) return; { #if EV_SELECT_USE_FD_SET #if EV_SELECT_IS_WINSOCKET SOCKET handle = anfds [fd].handle; #else int handle = fd; #endif if (nev & EV_READ) FD_SET (handle, (fd_set *)vec_ri); else FD_CLR (handle, (fd_set *)vec_ri); if (nev & EV_WRITE) FD_SET (handle, (fd_set *)vec_wi); else FD_CLR (handle, (fd_set *)vec_wi); #else int word = fd / NFDBITS; int mask = 1UL << (fd % NFDBITS); if (vec_max < word + 1) { int new_max = word + 1; vec_ri = ev_realloc (vec_ri, new_max * NFDBYTES); vec_ro = ev_realloc (vec_ro, new_max * NFDBYTES); /* could free/malloc */ vec_wi = ev_realloc (vec_wi, new_max * NFDBYTES); vec_wo = ev_realloc (vec_wo, new_max * NFDBYTES); /* could free/malloc */ for (; vec_max < new_max; ++vec_max) ((fd_mask *)vec_ri)[vec_max] = ((fd_mask *)vec_wi)[vec_max] = 0; } ((fd_mask *)vec_ri) [word] |= mask; if (!(nev & EV_READ)) ((fd_mask *)vec_ri) [word] &= ~mask; ((fd_mask *)vec_wi) [word] |= mask; if (!(nev & EV_WRITE)) ((fd_mask *)vec_wi) [word] &= ~mask; #endif } } static void select_poll (EV_P_ ev_tstamp timeout) { struct timeval tv; int res; #if EV_SELECT_USE_FD_SET memcpy (vec_ro, vec_ri, sizeof (fd_set)); memcpy (vec_wo, vec_wi, sizeof (fd_set)); #else memcpy (vec_ro, vec_ri, vec_max * NFDBYTES); memcpy (vec_wo, vec_wi, vec_max * NFDBYTES); #endif tv.tv_sec = (long)timeout; tv.tv_usec = (long)((timeout - (ev_tstamp)tv.tv_sec) * 1e6); res = select (vec_max * NFDBITS, (fd_set *)vec_ro, (fd_set *)vec_wo, 0, &tv); if (res < 0) { #if EV_SELECT_IS_WINSOCKET errno = WSAGetLastError (); #endif if (errno == EBADF) fd_ebadf (EV_A); else if (errno == ENOMEM && !syserr_cb) fd_enomem (EV_A); else if (errno != EINTR) syserr ("(libev) select"); return; } #if EV_SELECT_USE_FD_SET { int fd; for (fd = 0; fd < anfdmax; ++fd) if (anfds [fd].events) { int events = 0; #if EV_SELECT_IS_WINSOCKET SOCKET handle = anfds [fd].handle; #else int handle = fd; #endif if (FD_ISSET (handle, (fd_set *)vec_ro)) events |= EV_READ; if (FD_ISSET (handle, (fd_set *)vec_wo)) events |= EV_WRITE; if (events) fd_event (EV_A_ fd, events); } } #else { int word, bit; for (word = vec_max; word--; ) { fd_mask word_r = ((fd_mask *)vec_ro) [word]; fd_mask word_w = ((fd_mask *)vec_wo) [word]; if (word_r || word_w) for (bit = NFDBITS; bit--; ) { fd_mask mask = 1UL << bit; int events = 0; events |= word_r & mask ? EV_READ : 0; events |= word_w & mask ? EV_WRITE : 0; if (events) fd_event (EV_A_ word * NFDBITS + bit, events); } } } #endif } static int select_init (EV_P_ int flags) { method_fudge = 1e-2; /* needed to compensate for select returning early, very conservative */ method_modify = select_modify; method_poll = select_poll; #if EV_SELECT_USE_FD_SET vec_max = FD_SETSIZE / 32; vec_ri = ev_malloc (sizeof (fd_set)); FD_ZERO ((fd_set *)vec_ri); vec_ro = ev_malloc (sizeof (fd_set)); vec_wi = ev_malloc (sizeof (fd_set)); FD_ZERO ((fd_set *)vec_wi); vec_wo = ev_malloc (sizeof (fd_set)); #else vec_max = 0; vec_ri = 0; vec_ri = 0; vec_wo = 0; vec_wo = 0; #endif return EVMETHOD_SELECT; } static void select_destroy (EV_P) { ev_free (vec_ri); ev_free (vec_ro); ev_free (vec_wi); ev_free (vec_wo); }