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/* Synchronous I/O multiplexing. Linux/microblaze version.
Copyright (C) 2019-2020 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 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
<https://www.gnu.org/licenses/>. */
#include <errno.h>
#include <signal.h>
#include <time.h>
#include <sys/poll.h>
#include <sysdep-cancel.h>
#ifndef __ASSUME_PSELECT
# define __pselect __pselect_syscall
#endif
/* If pselect is supported, just use the Linux generic implementation. */
#include <sysdeps/unix/sysv/linux/pselect.c>
#ifndef __ASSUME_PSELECT
# undef __pselect
int
__pselect (int nfds, fd_set *readfds, fd_set *writefds, fd_set *exceptfds,
const struct timespec *timeout, const sigset_t *sigmask)
{
int ret = __pselect_syscall (nfds, readfds, writefds, exceptfds, timeout,
sigmask);
if (ret >= 0 || errno != ENOSYS)
return ret;
/* The fallback uses 'select' which shows the race condition regarding
signal mask set/restore, requires two additional syscalls, and has
a worse timeout precision (microseconds instead of nanoseconds). */
struct timeval tval, *ptval = NULL;
if (timeout != NULL)
{
if (! valid_nanoseconds (timeout->tv_nsec))
{
__set_errno (EINVAL);
return -1;
}
TIMESPEC_TO_TIMEVAL (&tval, timeout);
ptval = &tval;
}
sigset_t savemask;
if (sigmask != NULL)
__sigprocmask (SIG_SETMASK, sigmask, &savemask);
/* select itself is a cancellation entrypoint. */
ret = __select (nfds, readfds, writefds, exceptfds, ptval);
if (sigmask != NULL)
__sigprocmask (SIG_SETMASK, &savemask, NULL);
return ret;
}
weak_alias (__pselect, pselect)
#endif
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