On Thu, Oct 05, 2000 at 07:47:50PM +0200, Poul-Henning Kamp wrote:
>
> Hi,
>
> I found a bug in rsync 2.4.6 + rsync-246-v6-20000907.diff.gz:
>
> The following tiny script demonstrates a bug in the --copy-unsafe-links
> code: If the destination of the symbolic link doesn't exist on the
> source system, it is not copied across to the destination system:
>
> #!/bin/sh
> rm -rf s d
> mkdir s
> ln -s /foo/glaf/glam s/a
> touch s/e
> ln -s e s/f
> mkdir d
> rsync -rv \
> -l \
> --copy-unsafe-links \
> s/. ./d
> echo "----S"
> find s -ls
> echo "----D"
> find d -ls
>
> Running it yields this result:
>
> building file list ... readlink a: No such file or directory
> done
> e
> f -> e
> wrote 95 bytes read 36 bytes 262.00 bytes/sec
> total size is 1 speedup is 0.01
> ----S
> drwxrwxr-x 2 phk phk 512 5 Okt 19:41 s
> lrwxrwxr-x 1 phk phk 14 5 Okt 19:41 s/a -> /foo/glaf/glam
> -rw-rw-r-- 1 phk phk 0 5 Okt 19:41 s/e
> lrwxrwxr-x 1 phk phk 1 5 Okt 19:41 s/f -> e
> ----D
> drwxrwxr-x 2 phk phk 512 5 Okt 19:41 d
> -rw-rw-r-- 1 phk phk 0 5 Okt 19:41 d/e
> lrwxrwxrwx 1 phk phk 1 5 Okt 19:41 d/f -> e
>
> Apply this patch:
>
> --- flist.c.old Wed Sep 6 04:46:43 2000
> +++ flist.c Thu Oct 5 19:32:22 2000
> @@ -154,7 +154,7 @@
> return -1;
> }
> Linkbuf[l] = 0;
> - if (copy_unsafe_links && (topsrcname[0] != '\0') &&
> + if (!copy_unsafe_links && (topsrcname[0] != '\0') &&
> unsafe_symlink(Linkbuf, topsrcname)) {
> return do_stat(Path, Buffer);
> }
>
> And the result looks better:
>
> building file list ... done
> a -> /foo/glaf/glam
> e
> f -> e
> wrote 124 bytes read 36 bytes 320.00 bytes/sec
> total size is 15 speedup is 0.09
> ----S
> drwxrwxr-x 2 phk phk 512 5 Okt 19:43 s
> lrwxrwxr-x 1 phk phk 14 5 Okt 19:43 s/a -> /foo/glaf/glam
> -rw-rw-r-- 1 phk phk 0 5 Okt 19:43 s/e
> lrwxrwxr-x 1 phk phk 1 5 Okt 19:43 s/f -> e
> ----D
> drwxrwxr-x 2 phk phk 512 5 Okt 19:43 d
> lrwxrwxrwx 1 phk phk 14 5 Okt 19:43 d/a -> /foo/glaf/glam
> -rw-rw-r-- 1 phk phk 0 5 Okt 19:43 d/e
> lrwxrwxrwx 1 phk phk 1 5 Okt 19:43 d/f -> e
>
> --
> Poul-Henning Kamp | UNIX since Zilog Zeus 3.20
> [EMAIL PROTECTED] | TCP/IP since RFC 956
> FreeBSD coreteam member | BSD since 4.3-tahoe
> Never attribute to malice what can adequately be explained by incompetence.
>
You are misunderstanding what the meaning of --copy-unsafe-links is. From
the man page:
This tells rsync to treat symbolic links that point
outside the source tree like ordinary files. Abso-
lute symlinks are also treated like ordinary files,
and so are any symlinks in the source path itself
when --relative is used.
To treat a file like an ordinary file means to copy it in on the
destination, not treat it like a link. So if a symlink points nowhere,
rsync has to ignore it or print an error, and it chooses to ignore it.
- Dave Dykstra
