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/* Copyright (C) 2006-2018 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Ulrich Drepper <drepper@redhat.com>, 2006.
The GNU C Library 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.
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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<http://www.gnu.org/licenses/>. */
#include <errno.h>
#include <limits.h>
#include <signal.h>
#include <stddef.h> /* For NULL. */
#include <sys/poll.h>
#include <sysdep-cancel.h>
int
ppoll (struct pollfd *fds, nfds_t nfds, const struct timespec *timeout,
const sigset_t *sigmask)
{
int tval = -1;
/* poll uses a simple millisecond value. Convert it. */
if (timeout != NULL)
{
if (timeout->tv_sec < 0
|| timeout->tv_nsec < 0 || timeout->tv_nsec >= 1000000000)
{
__set_errno (EINVAL);
return -1;
}
if (timeout->tv_sec > INT_MAX / 1000
|| (timeout->tv_sec == INT_MAX / 1000
&& ((timeout->tv_nsec + 999999) / 1000000 > INT_MAX % 1000)))
/* We cannot represent the timeout in an int value. Wait
forever. */
tval = -1;
else
tval = (timeout->tv_sec * 1000
+ (timeout->tv_nsec + 999999) / 1000000);
}
/* The setting and restoring of the signal mask and the select call
should be an atomic operation. This can't be done without kernel
help. */
sigset_t savemask;
if (sigmask != NULL)
__sigprocmask (SIG_SETMASK, sigmask, &savemask);
/* Note the ppoll() is a cancellation point. But since we call
poll() which itself is a cancellation point we do not have
to do anything here. */
int retval = __poll (fds, nfds, tval);
if (sigmask != NULL)
__sigprocmask (SIG_SETMASK, &savemask, NULL);
return retval;
}
#ifndef ppoll
/* __poll handles cancellation. */
LIBC_CANCEL_HANDLED ();
libc_hidden_def (ppoll);
#endif
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