X-Git-Url: https://git.llucax.com/software/libev.git/blobdiff_plain/cc75a05531d9d05ac14fdaec7960b1c970c87bbb..08f366939c60afffe3eb0bf658f52a607c8bb693:/ev_select.c?ds=sidebyside diff --git a/ev_select.c b/ev_select.c index e69de29..7fe9084 100644 --- a/ev_select.c +++ b/ev_select.c @@ -0,0 +1,229 @@ +/* + * libev select fd activity backend + * + * Copyright (c) 2007 Marc Alexander Lehmann + * 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. + */ + +/* for unix systems */ +#if WIN32 +typedef unsigned int uint32_t; +# ifndef EV_SELECT_USE_FD_SET +# define EV_SELECT_USE_FD_SET 1 +# endif +#else +# include +# include +#endif + +#if EV_SELECT_USE_WIN32_HANDLES +# undef EV_SELECT_USE_FD_SET +# define EV_SELECT_USE_FD_SET 1 +#endif + +#include + +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_USE_WIN32_HANDLES + fd = _get_osfhandle (fd); + if (fd < 0) + return; +# endif + + if (nev & EV_READ) + FD_SET (fd, (struct fd_set *)vec_ri); + else + FD_CLR (fd, (struct fd_set *)vec_ri); + + if (nev & EV_WRITE) + FD_SET (fd, (struct fd_set *)vec_wi); + else + FD_CLR (fd, (struct fd_set *)vec_wi); +#else + { + int offs = fd >> 3; + int mask = 1 << (fd & 7); + + if (vec_max < (fd >> 5) + 1) + { + int new_max = (fd >> 5) + 1; + + vec_ri = (unsigned char *)ev_realloc (vec_ri, new_max * 4); + vec_ro = (unsigned char *)ev_realloc (vec_ro, new_max * 4); /* could free/malloc */ + vec_wi = (unsigned char *)ev_realloc (vec_wi, new_max * 4); + vec_wo = (unsigned char *)ev_realloc (vec_wo, new_max * 4); /* could free/malloc */ + + for (; vec_max < new_max; ++vec_max) + ((uint32_t *)vec_ri)[vec_max] = + ((uint32_t *)vec_wi)[vec_max] = 0; + } + + vec_ri [offs] |= mask; + if (!(nev & EV_READ)) + vec_ri [offs] &= ~mask; + + vec_wi [offs] |= mask; + if (!(nev & EV_WRITE)) + vec_wi [offs] &= ~mask; + } +#endif +} + +static void +select_poll (EV_P_ ev_tstamp timeout) +{ + int word, offs; + struct timeval tv; + int res; + +#if EV_SELECT_USE_FD_SET + memcpy (vec_ro, vec_ri, sizeof (struct fd_set)); + memcpy (vec_wo, vec_wi, sizeof (struct fd_set)); +#else + memcpy (vec_ro, vec_ri, vec_max * 4); + memcpy (vec_wo, vec_wi, vec_max * 4); +#endif + + tv.tv_sec = (long)timeout; + tv.tv_usec = (long)((timeout - (ev_tstamp)tv.tv_sec) * 1e6); + + res = select (vec_max * 32, (fd_set *)vec_ro, (fd_set *)vec_wo, 0, &tv); + + if (res < 0) + { +#ifdef WIN32 + if (errno == WSAEINTR ) errno = EINTR; + if (errno == WSAENOTSOCK) errno = EBADF; +#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 +# if EV_SELECT_USE_WIN32_HANDLES + for (word = 0; word < anfdmax; ++word) + { + if (!anfd [word].events) + { + int fd = _get_osfhandle (word); + + if (fd >= 0) + { + int events = 0; + + if (FD_ISSET (fd, (struct fd_set *)vec_ro)) events |= EV_READ; + if (FD_ISSET (fd, (struct fd_set *)vec_wo)) events |= EV_WRITE; + + if (events) + fd_event (EV_A_ word, events); + } + } + } +# else + for (word = 0; word < FD_SETSIZE; ++word) + { + int events = 0; + if (FD_ISSET (word, (struct fd_set *)vec_ro)) events |= EV_READ; + if (FD_ISSET (word, (struct fd_set *)vec_wo)) events |= EV_WRITE; + + if (events) + fd_event (EV_A_ word, events); + } +# endif +#else + for (word = vec_max; word--; ) + { + if (((uint32_t *)vec_ro) [word] | ((uint32_t *)vec_wo) [word]) + for (offs = 4; offs--; ) + { + int idx = word * 4 + offs; + unsigned char byte_r = vec_ro [idx]; + unsigned char byte_w = vec_wo [idx]; + int bit; + + if (byte_r | byte_w) + for (bit = 8; bit--; ) + { + int events = 0; + events |= byte_r & (1 << bit) ? EV_READ : 0; + events |= byte_w & (1 << bit) ? EV_WRITE : 0; + + if (events) + fd_event (EV_A_ idx * 8 + 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 (struct fd_set)); FD_ZERO ((struct fd_set *)vec_ri); + vec_ro = ev_malloc (sizeof (struct fd_set)); + vec_wi = ev_malloc (sizeof (struct fd_set)); FD_ZERO ((struct fd_set *)vec_wi); + vec_wo = ev_malloc (sizeof (struct 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); +} + +