/* 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;
}
/* Read the contents of the symbolic link FILE_NAME relative to FD into no more
than LEN bytes of BUF. The contents are not null-terminated.
Returns the number of characters read, or -1 for errors. */
ssize_t
readlinkat (int fd, const char *file_name, char *buf, size_t len)
{
error_t err;
file_t file;
struct stat64 st;
file = __file_name_lookup_at (fd, 0, file_name, O_READ | O_NOLINK, 0);
if (file == MACH_PORT_NULL)
return -1;
err = __io_stat (file, &st);
if (! err)
if (S_ISLNK (st.st_mode))
{
char *rbuf = buf;
err = __io_read (file, &rbuf, &len, 0, len);
if (!err && rbuf != buf)
{
memcpy (buf, rbuf, len);
__vm_deallocate (__mach_task_self (), (vm_address_t)rbuf, len);
}
}
else
err = EINVAL;
__mach_port_deallocate (__mach_task_self (), file);
return err ? __hurd_fail (err) : len;
}
int
fchmodat (int fd, const char *file, mode_t mode, int flag)
{
error_t err;
file_t port = __file_name_lookup_at (fd, flag, file, 0, 0);
if (port == MACH_PORT_NULL)
return -1;
err = __file_chmod (port, mode);
__mach_port_deallocate (__mach_task_self (), port);
if (err)
return __hurd_fail (err);
return 0;
}
/* Get information about the file descriptor FD in BUF. */
int
__fxstatat64 (int vers, int fd, const char *filename, struct stat64 *buf,
int flag)
{
error_t err;
io_t port;
if (vers != _STAT_VER)
return __hurd_fail (EINVAL);
port = __file_name_lookup_at (fd, flag, filename, 0, 0);
if (port == MACH_PORT_NULL)
return -1;
err = __io_stat (port, buf);
__mach_port_deallocate (__mach_task_self (), port);
return __hurd_fail (err);
}
