glibc/sysdeps/mach/hurd/linkat.c

63 lines
2.1 KiB
C

/* Make a link between file names relative to open directories. Hurd version.
Copyright (C) 2006-2016 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
<http://www.gnu.org/licenses/>. */
#include <errno.h>
#include <fcntl.h>
#include <stddef.h>
#include <unistd.h>
#include <hurd.h>
#include <hurd/fd.h>
/* Make a link to FROM relative to FROMFD called TO relative to TOFD. */
int
linkat (int fromfd, const char *from, int tofd, const char *to, int flags)
{
error_t err;
file_t oldfile, linknode, todir;
char *toname;
/* POSIX says linkat doesn't follow symlinks by default, so pass
O_NOLINK. That can be overridden by AT_SYMLINK_FOLLOW in FLAGS. */
oldfile = __file_name_lookup_at (fromfd, flags, from, O_NOLINK, 0);
if (oldfile == MACH_PORT_NULL)
return -1;
/* The file_getlinknode RPC returns the port that should be passed to
the receiving filesystem (the one containing TODIR) in dir_link. */
err = __file_getlinknode (oldfile, &linknode);
__mach_port_deallocate (__mach_task_self (), oldfile);
if (err)
return __hurd_fail (err);
todir = __file_name_split_at (tofd, to, &toname);
if (todir != MACH_PORT_NULL)
{
err = __dir_link (todir, linknode, toname, 1);
__mach_port_deallocate (__mach_task_self (), todir);
}
__mach_port_deallocate (__mach_task_self (), linknode);
if (todir == MACH_PORT_NULL)
return -1;
if (err)
return __hurd_fail (err);
return 0;
}