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/***
This file is part of PulseAudio.
Copyright 2006 Pierre Ossman <ossman@cendio.se> for Cendio AB
PulseAudio is free software; you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License as published
by the Free Software Foundation; either version 2.1 of the License,
or (at your option) any later version.
PulseAudio 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
General Public License for more details.
You should have received a copy of the GNU Lesser General Public License
along with PulseAudio; if not, see <http://www.gnu.org/licenses/>.
***/
/***
Based on work for the GNU C Library.
Copyright (C) 1994, 1996, 1997 Free Software Foundation, Inc.
***/
/* 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
#ifdef HAVE_SYS_IOCTL_H
#include <sys/ioctl.h>
#endif
#include <errno.h>
#include <fcntl.h>
#ifdef HAVE_SYS_SELECT_H
#include <sys/select.h>
#endif
#include <pulsecore/socket.h>
#include <pulsecore/core-util.h>
#include <pulse/util.h>
#include "poll.h"
/* Mac OSX fails to implement poll() in a working way since 10.4. IOW, for
* several years. We need to enable a dirty workaround and emulate that call
* with select(), just like for Windows. sic! */
#if !defined(HAVE_POLL_H) || defined(OS_IS_DARWIN)
int pa_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;
#ifdef OS_IS_WIN32
char data[64];
#endif
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(maxfd + 1, &rset, &wset, &xset, (timeout == -1 ? NULL : &tv));
if ((ready == -1) && (errno == EBADF)) {
ready = 0;
maxfd = -1;
#ifdef OS_IS_WIN32
/*
* Windows has no fcntl(), so we have to trick around with more
* select() calls to find out what went wrong
*/
FD_ZERO (&rset);
FD_ZERO (&wset);
FD_ZERO (&xset);
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(f->fd, &rset, &wset, &xset, &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;
}
}
}
#else /* !OS_IS_WIN32 */
for (f = fds; f < &fds[nfds]; f++)
if (f->fd != -1) {
/* use fcntl() to find out whether the descriptor is valid */
if (fcntl(f->fd, F_GETFL) != -1) {
if (f->fd > maxfd && (f->events & (POLLIN|POLLOUT|POLLPRI))) {
maxfd = f->fd;
ready++;
}
} else {
FD_CLR(f->fd, &rset);
FD_CLR(f->fd, &wset);
FD_CLR(f->fd, &xset);
}
}
#endif
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(maxfd + 1, &rset, &wset, &xset, (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! */
#ifdef OS_IS_DARWIN
/* There is a bug in Mac OS X that causes it to ignore MSG_PEEK
* for some kinds of descriptors. Detect if this descriptor is a
* connected socket, a server socket, or something else using a
* 0-byte recv, and use ioctl(2) to detect POLLHUP. */
int r = recv(f->fd, NULL, 0, MSG_PEEK);
if (r == 0 || (r < 0 && errno == ENOTSOCK))
ioctl(f->fd, FIONREAD, &r);
if (r == 0)
f->revents |= POLLHUP;
#else /* !OS_IS_DARWIN */
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;
}
}
#endif
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 */
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