glibc/io/close_range.c

45 lines
1.3 KiB
C

/* Close a range of file descriptors.
Copyright (C) 2021-2024 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 <not-cancel.h>
#include <unistd.h>
/* Close the file descriptors from FIRST up to LAST, inclusive. */
int
__close_range (unsigned int first, unsigned int last,
int flags)
{
if (first > last || flags != 0)
{
__set_errno (EINVAL);
return -1;
}
int maxfd = __getdtablesize ();
if (maxfd == -1)
return -1;
for (int i = first; i <= last && i < maxfd; i++)
__close_nocancel_nostatus (i);
return 0;
}
libc_hidden_def (__close_range)
weak_alias (__close_range, close_range)