mirror of
https://sourceware.org/git/glibc.git
synced 2024-12-23 03:10:05 +00:00
79 lines
2.7 KiB
C
79 lines
2.7 KiB
C
/* Copyright (C) 1996-2017 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 <errno.h>
|
|
#include <signal.h>
|
|
#include <stddef.h> /* For NULL. */
|
|
#include <sys/time.h>
|
|
#include <sys/select.h>
|
|
#include <sysdep-cancel.h>
|
|
|
|
|
|
/* Check the first NFDS descriptors each in READFDS (if not NULL) for read
|
|
readiness, in WRITEFDS (if not NULL) for write readiness, and in EXCEPTFDS
|
|
(if not NULL) for exceptional conditions. If TIMEOUT is not NULL, time out
|
|
after waiting the interval specified therein. Additionally set the sigmask
|
|
SIGMASK for this call. Returns the number of ready descriptors, or -1 for
|
|
errors. */
|
|
int
|
|
__pselect (int nfds, fd_set *readfds, fd_set *writefds, fd_set *exceptfds,
|
|
const struct timespec *timeout, const sigset_t *sigmask)
|
|
{
|
|
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)
|
|
{
|
|
/* Catch bugs which would be hidden by the TIMESPEC_TO_TIMEVAL
|
|
computations. The division by 1000 truncates values. */
|
|
if (__glibc_unlikely (timeout->tv_nsec < 0))
|
|
{
|
|
__set_errno (EINVAL);
|
|
return -1;
|
|
}
|
|
|
|
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);
|
|
|
|
/* 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 = __select (nfds, readfds, writefds, exceptfds,
|
|
timeout != NULL ? &tval : NULL);
|
|
|
|
if (sigmask != NULL)
|
|
__sigprocmask (SIG_SETMASK, &savemask, NULL);
|
|
|
|
return retval;
|
|
}
|
|
#ifndef __pselect
|
|
weak_alias (__pselect, pselect)
|
|
/* __select handles cancellation. */
|
|
LIBC_CANCEL_HANDLED ();
|
|
#endif
|