glibc/sysdeps/mach/hurd/symlinkat.c

76 lines
2.4 KiB
C

/* Create a symbolic link named relative to an open directory. Hurd version.
Copyright (C) 1991-2013 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/paths.h>
#include <hurd/fd.h>
#include <string.h>
/* Make a link to FROM called TO relative to FD. */
int
symlinkat (from, fd, to)
const char *from;
int fd;
const char *to;
{
error_t err;
file_t dir, node;
char *name;
const size_t len = strlen (from) + 1;
char buf[sizeof (_HURD_SYMLINK) + len];
/* A symlink is a file whose translator is "/hurd/symlink\0target\0". */
memcpy (buf, _HURD_SYMLINK, sizeof (_HURD_SYMLINK));
memcpy (&buf[sizeof (_HURD_SYMLINK)], from, len);
dir = __file_name_split_at (fd, to, &name);
if (dir == MACH_PORT_NULL)
return -1;
/* Create a new, unlinked node in the target directory. */
err = __dir_mkfile (dir, O_WRITE, 0777 & ~_hurd_umask, &node);
if (! err)
{
/* Set the node's translator to make it a symlink. */
err = __file_set_translator (node,
FS_TRANS_EXCL|FS_TRANS_SET,
FS_TRANS_EXCL|FS_TRANS_SET, 0,
buf, sizeof (_HURD_SYMLINK) + len,
MACH_PORT_NULL, MACH_MSG_TYPE_COPY_SEND);
if (! err)
/* Link the node, now a valid symlink, into the target directory. */
err = __dir_link (dir, node, name, 1);
__mach_port_deallocate (__mach_task_self (), node);
}
__mach_port_deallocate (__mach_task_self (), dir);
if (err)
return __hurd_fail (err);
return 0;
}