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/* Copyright (C) 1996-1998,2001,2002,2003,2006 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Ulrich Drepper <drepper@cygnus.com>, 1996.
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 <features.h>
#ifdef __USE_XOPEN2K
#include <sys/syscall.h>
#include <sys/select.h>
#include <sys/time.h>
#include <signal.h>
#include <cancel.h>
static int __NC(pselect)(int nfds, fd_set *readfds, fd_set *writefds,
fd_set *exceptfds, const struct timespec *timeout,
const sigset_t *sigmask)
{
#ifdef __NR_pselect6
/* The Linux kernel can in some situations update the timeout value.
* We do not want that so use a local variable.
*/
struct timespec _ts;
if (timeout != NULL) {
_ts = *timeout;
timeout = &_ts;
}
/* Note: the system call expects 7 values but on most architectures
we can only pass in 6 directly. If there is an architecture with
support for more parameters a new version of this file needs to
be created. */
struct {
__kernel_ulong_t ss;
__kernel_size_t ss_len;
} data;
if (sigmask != NULL) {
data.ss = (__kernel_ulong_t) sigmask;
data.ss_len = __SYSCALL_SIGSET_T_SIZE;
sigmask = (void *)&data;
}
return INLINE_SYSCALL(pselect6, 6, nfds, readfds, writefds, exceptfds, timeout, sigmask);
#else
struct timeval tval;
int retval;
sigset_t savemask;
/* Change nanosecond number to microseconds. This might mean losing
precision and therefore the `pselect` should be available. But
for now it is hardly found. */
if (timeout != NULL)
TIMESPEC_TO_TIMEVAL (&tval, timeout);
/* 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. */
if (sigmask != NULL)
sigprocmask (SIG_SETMASK, sigmask, &savemask);
/* The comment below does not apply on uClibc, since we use __select_nocancel */
/* Note the pselect() is a cancellation point. But since we call
select() which itself is a cancellation point we do not have
to do anything here. */
retval = __NC(select)(nfds, readfds, writefds, exceptfds,
timeout != NULL ? &tval : NULL);
if (sigmask != NULL)
sigprocmask (SIG_SETMASK, &savemask, NULL);
return retval;
#endif
}
CANCELLABLE_SYSCALL(int, pselect, (int nfds, fd_set *readfds, fd_set *writefds, fd_set *exceptfds,
const struct timespec *timeout, const sigset_t *sigmask),
(nfds, readfds, writefds, exceptfds, timeout, sigmask))
#endif
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