diff options
Diffstat (limited to 'src/polypcore/poll.c')
| -rw-r--r-- | src/polypcore/poll.c | 190 |
1 files changed, 190 insertions, 0 deletions
diff --git a/src/polypcore/poll.c b/src/polypcore/poll.c new file mode 100644 index 000000000..193fc8128 --- /dev/null +++ b/src/polypcore/poll.c @@ -0,0 +1,190 @@ +/* $Id$ */ + +/*** + Copyright (C) 1994, 1996, 1997 Free Software Foundation, Inc. + Copyright (C) 2005, Cendio AB. + This file is part of polypaudio. + Based on work for the GNU C Library. + + polypaudio 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. + + polypaudio 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 polypaudio; If not, write to the Free Software + Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, + USA. +***/ + +/* 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. */ + +#ifdef HAVE_CONFIG_H +#include <config.h> +#endif + +#include <errno.h> + +#ifdef HAVE_SYS_SELECT_H +#include <sys/select.h> +#endif + +#include "winsock.h" + +#ifndef HAVE_SYS_POLL_H + +#include "util.h" +#include "poll.h" + +int poll (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; + char data[64]; + + FD_ZERO (&rset); + FD_ZERO (&wset); + FD_ZERO (&xset); + + if (nfds == 0) { + if (timeout >= 0) { + pa_msleep(timeout); + return 0; + } + +#ifdef OS_IS_WIN32 + /* + * Windows does not support signals properly so waiting for them would + * mean a deadlock. + */ + pa_msleep(100); + return 0; +#else + return select(0, NULL, NULL, NULL, NULL); +#endif + } + + for (f = fds; f < &fds[nfds]; ++f) { + if (f->fd != -1) { + 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 % 1000) * 1000; + + ready = select ((SELECT_TYPE_ARG1) maxfd + 1, SELECT_TYPE_ARG234 &rset, + SELECT_TYPE_ARG234 &wset, SELECT_TYPE_ARG234 &xset, + SELECT_TYPE_ARG5 (timeout == -1 ? NULL : &tv)); + if ((ready == -1) && (errno == EBADF)) { + ready = 0; + + FD_ZERO (&rset); + FD_ZERO (&wset); + FD_ZERO (&xset); + + maxfd = -1; + + for (f = fds; f < &fds[nfds]; ++f) { + if (f->fd != -1) { + fd_set sngl_rset, sngl_wset, sngl_xset; + + FD_ZERO (&sngl_rset); + FD_ZERO (&sngl_wset); + FD_ZERO (&sngl_xset); + + if (f->events & POLLIN) + FD_SET (f->fd, &sngl_rset); + if (f->events & POLLOUT) + FD_SET (f->fd, &sngl_wset); + if (f->events & POLLPRI) + FD_SET (f->fd, &sngl_xset); + if (f->events & (POLLIN|POLLOUT|POLLPRI)) { + struct timeval singl_tv; + + singl_tv.tv_sec = 0; + singl_tv.tv_usec = 0; + + if (select((SELECT_TYPE_ARG1) f->fd, SELECT_TYPE_ARG234 &rset, + SELECT_TYPE_ARG234 &wset, SELECT_TYPE_ARG234 &xset, + SELECT_TYPE_ARG5 &singl_tv) != -1) { + 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; + ++ready; + } else if (errno == EBADF) + f->revents |= POLLNVAL; + } + } + } + + if (ready) { + /* Linux alters the tv struct... but it shouldn't matter here ... + * as we're going to be a little bit out anyway as we've just eaten + * more than a couple of cpu cycles above */ + ready = select ((SELECT_TYPE_ARG1) maxfd + 1, SELECT_TYPE_ARG234 &rset, + SELECT_TYPE_ARG234 &wset, SELECT_TYPE_ARG234 &xset, + SELECT_TYPE_ARG5 (timeout == -1 ? NULL : &tv)); + } + } + +#ifdef OS_IS_WIN32 + errno = WSAGetLastError(); +#endif + + if (ready > 0) { + ready = 0; + for (f = fds; f < &fds[nfds]; ++f) { + f->revents = 0; + if (f->fd != -1) { + if (FD_ISSET (f->fd, &rset)) { + /* support for POLLHUP. An hung up descriptor does not + increase the return value! */ + if (recv (f->fd, data, 64, MSG_PEEK) == -1) { + if (errno == ESHUTDOWN || errno == ECONNRESET || + errno == ECONNABORTED || errno == ENETRESET) { + fprintf(stderr, "Hangup\n"); + f->revents |= POLLHUP; + } + } + + if (f->revents == 0) + f->revents |= POLLIN; + } + if (FD_ISSET (f->fd, &wset)) + f->revents |= POLLOUT; + if (FD_ISSET (f->fd, &xset)) + f->revents |= POLLPRI; + } + if (f->revents) + ready++; + } + } + + return ready; +} + +#endif /* HAVE_SYS_POLL_H */ |