Since e0d7b49 (first appeared in bookworm) fcopy tests for broken symlinks. However this change breaks relative symlinks because of class semantics (/foo/bar/DEFAULT -> ../etc means /foo/bar should be a symlink relative to bar, not to DEFAULT in the target tree). Also during installation, absolute symlinks pointing to files absent in the installer will be ignored by fcopy.

e0d7b49 was a fix for #985303. I'm not sure what the correct behaviour would be for that, since we don't use substitutions.

Does fcopy works for you without this change for broken/relative symlinks?
Does fcopy handles relative symlinks diffrently than absolute
symlinks?

Do you have any suggestion how fcopy should behave for symlinks?

Hello Thomas,
Yes. We just revert the change since bookworm.
symlinks?
No, AFAIK. Just that absolute symlinks which might work in a running system won't during installation.
For dead symlinks as source without -H: just die like in do_substitutions (having a dead symlink in the context of the configspace should be an configuration error), or continue with a warning (no strong preference there).

For healthy symlinks without -H and with -S: do substitutions as normal.

I attached an untested patch which might do that; Will test the next days.

Kind regards,
Victor

Attached a patch without the duplicated '-l $sourcefile'

And some tests:

$ mkdir --parents config/normal_file config/absolute_in-tree_symlink config/absolute_out-of-tree_symlink config/etc/relative_in-tree_symlink config/etc/relative_out-of-tree_symlink
$ echo '{%PATH%}' > config/normal_file/DEFAULT
$ ln -s /normal_file config/absolute_in-tree_symlink/DEFAULT
$ ln -s /tmp/fai/fai.log config/absolute_out-of-tree_symlink/DEFAULT
$ ln -s ../normal_file config/etc/relative_in-tree_symlink/DEFAULT
$ ln -s ../etc/debian_version config/etc/relative_out-of-tree_symlink/DEFAULT

Without patch:
$ fcopy.orig -s config -t target -c DEFAULT -rHS /
fcopy: config/absolute_in-tree_symlink/DEFAULT is a broken symlink
# Even though normal_file will be copied later, at this point the symlink is broken (and later it would still be, because -t is not /)

fcopy: config/etc/relative_in-tree_symlink/DEFAULT is a broken symlink
# In the target tree ../normal_file will be fine, but config/etc/relative_in-tree_symlink/../normal_file doesn't resolve

fcopy: config/absolute_out-of-tree_symlink/DEFAULT is a broken symlink
# This would only work during installation

fcopy: copied config/normal_file/DEFAULT to target/normal_file
# Ok

fcopy: config/etc/relative_out-of-tree_symlink/DEFAULT is a broken symlink
# Similar reason to relative_in-tree_symlink

$ cat target/normal_file
/usr/local/bin:/usr/bin:/bin:/usr/local/games:/usr/games
# substitution worked

With patch:
$ fcopy -s config -t target -c DEFAULT -rHS /
fcopy: symlinked config/absolute_out-of-tree_symlink/DEFAULT -> /tmp/fai/fai.log to target/absolute_out-of-tree_symlink
fcopy: copied config/normal_file/DEFAULT to target/normal_file
fcopy: symlinked config/etc/relative_out-of-tree_symlink/DEFAULT -> ../etc/debian_version to target/etc/relative_out-of-tree_symlink
fcopy: symlinked config/etc/relative_in-tree_symlink/DEFAULT -> ../normal_file to target/etc/relative_in-tree_symlink
fcopy: symlinked config/absolute_in-tree_symlink/DEFAULT -> /normal_file to target/absolute_in-tree_symlink

$ cat target/normal_file
/usr/local/bin:/usr/bin:/bin:/usr/local/games:/usr/games

With patch and without -H still as expected:
$ mkdir --parents config/some_file target
$ echo '{%PATH%}' > config/some_file/OTHER_CLASS
$ ln -s OTHER_CLASS config/some_file/DEFAULT
$ fcopy -s config -t target -c DEFAULT -r /
fcopy: copied config/some_file/DEFAULT to target/some_file
$ cat target/some_file
{%PATH%}

With -S too:
$ cat target/some_file
/usr/local/bin:/usr/bin:/bin:/usr/local/games:/usr/games