[golist] Issue #12: golist should be buildroot prefix aware

[Nicolas Mailhot]

nim reported a new issue against the project: `golist` that you are following:
``
The last stage of rpm packaging is copying a clean final copy of all the files that will
be shipped in an arborescence under a `%{buildroot}` prefix.

That is the deployment tree that is operated on to compute the actual requires and
provides rpm will generate.

As a consequence of this rpm design we can not change:

* the files operated on are not in their final place but under a root prefix
(`%{buildroot}/something` instead of `something`), and
* absolute symbolic links that point within the target deployment tree are left dangling
(they point to  `something`, when  `/something` is still at `%{buildroot}/something`)

Since *golist* is used to compute provides and requires for Go sources, and those sources
can include absolute symlinks, and will continue to prefer absolute symlinks over relative
symlinks because relative symlinks are quite hard to get right, *golist* needs to learn to
work in prefix mode, and learn to walk to `%{buildroot}/something` when encountering a
`/something` symlink in the source tree.
``

To reply, visit the link below or just reply to this email
https://pagure.io/golist/issue/12

[Elliott Sales de Andrade]

qulogic added a new comment to an issue you are following:
``
Is this not all handled when in `BUILD`? Or is something changing as to when `golist` is
called?
``

To reply, visit the link below or just reply to this email
https://pagure.io/golist/issue/12

[Nicolas Mailhot]

nim added a new comment to an issue you are following:
``
I don't remember where the files end up (under `BUILD` or `BUILDROOT`) and I may have
mixed up the rpm variable representing rpm's last stage staging directory.

The basic point is that for `Requires`/`Provides` we are not calling `golist` explicitly,
rpm is doing it in [generator](https://rpm.org/user_doc/dependency_generators.html) mode.
And the filesystem tree rpm is operating in generator mode is a mirror of the target FHS
structure, except `/` is replaced by a prefix directory.

That breaks absolute symlinks (they are already pointing to `/` not the prefix directory),
so anything that walks the directory structure like golist needs to have special code for
computing the correct symlink target in `Requires`/`Provides` generator mode. ie “the
symlink is pointing to `/foo/bar` but I’m in prefix mode so the actual target is probably
`/prefix/foo/bar/`”

This could probably be made better rpm upstream side by making `Requires`/`Provides` on a
container that fakes the root properly, but rpm was designed before containers existed and
getting the containing logic right is hard .
``

To reply, visit the link below or just reply to this email
https://pagure.io/golist/issue/12

[Nicolas Mailhot]

nim added a new comment to an issue you are following:
``
Ok, I found a workaround. Let’s focus on still broken things for now
``

To reply, visit the link below or just reply to this email
https://pagure.io/golist/issue/12

[Nicolas Mailhot]

The status of the issue: `golist should be buildroot prefix aware` of project: `golist`
has been updated to: Closed by nim.

https://pagure.io/golist/issue/12