diff options
Diffstat (limited to 'sysdeps/unix/bsd/poll.c')
-rw-r--r-- | sysdeps/unix/bsd/poll.c | 81 |
1 files changed, 81 insertions, 0 deletions
diff --git a/sysdeps/unix/bsd/poll.c b/sysdeps/unix/bsd/poll.c new file mode 100644 index 0000000000..4797ee04a1 --- /dev/null +++ b/sysdeps/unix/bsd/poll.c @@ -0,0 +1,81 @@ +/* Copyright (C) 1994 Free Software Foundation, Inc. +This file is part of the GNU C Library. + +The GNU C Library is free software; you can redistribute it and/or +modify it under the terms of the GNU Library General Public License as +published by the Free Software Foundation; either version 2 of the +License, or (at your option) any later version. + +The GNU C Library is distributed in the hope that it will be useful, +but WITHOUT ANY WARRANTY; without even the implied warranty of +MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU +Library General Public License for more details. + +You should have received a copy of the GNU Library General Public +License along with the GNU C Library; see the file COPYING.LIB. If +not, write to the Free Software Foundation, Inc., 675 Mass Ave, +Cambridge, MA 02139, USA. */ + +#include <sys/poll.h> +#include <sys/types.h> +#include <errno.h> +#include <string.h> +#include <sys/time.h> + +/* Poll the file descriptors described by the NFDS structures starting at + FDS. If TIMEOUT is nonzero and not -1, allow TIMEOUT milliseconds for + an event to occur; if TIMEOUT is -1, block until an event occurs. + Returns the number of file descriptors with events, zero if timed out, + or -1 for errors. */ + +int +poll (fds, nfds, timeout) + struct pollfd *fds; + unsigned long int nfds; + int timeout; +{ + struct timeval tv; + fd_set rset, wset, xset; + struct pollfd *f; + int ready; + int maxfd = 0; + + FD_ZERO (&rset); + FD_ZERO (&wset); + FD_ZERO (&xset); + + for (f = fds; f < &fds[nfds]; ++f) + if (f->fd >= 0) + { + if (f->events & POLLIN) + FD_SET (f->fd, &rset); + if (f->events & POLLOUT) + FD_SET (f->fd, &wset); + if (f->events & POLLPRI) + FD_SET (f->fd, &xset); + if (f->fd > maxfd && (f->events & (POLLIN|POLLOUT|POLLPRI))) + maxfd = f->fd; + } + + tv.tv_sec = timeout / 1000; + tv.tv_usec = (timeout + 999) / 1000; + + ready = __select (maxfd + 1, &rset, &wset, &xset, + timeout == -1 ? NULL : &tv); + if (ready > 0) + for (f = fds; f < &fds[nfds]; ++f) + { + f->revents = 0; + if (f->fd >= 0) + { + if (FD_ISSET (f->fd, &rset)) + f->revents |= POLLIN; + if (FD_ISSET (f->fd, &wset)) + f->revents |= POLLOUT; + if (FD_ISSET (f->fd, &xset)) + f->revents |= POLLPRI; + } + } + + return ready; +} |