svn commit: r308789 - head/sys/conf

[Warner Losh]

On Fri, Dec 23, 2016 at 9:35 AM, Ed Maste <emaste at freebsd.org> wrote:
> On 17 November 2016 at 19:13, Gleb Smirnoff <glebius at freebsd.org> wrote:
>> Author: glebius
>> Date: Fri Nov 18 00:13:30 2016
>> New Revision: 308789
>> URL: https://svnweb.freebsd.org/changeset/base/308789
>>
>> Log:
>>   If FreeBSD source tree is a subproject of a bigger project, then .git or
>>   .hg may reside above FreeBSD sources root.  Provide function findvcs()
>>   that will climb up and seek for presence of a VCS directory.
>
> This can incorrectly find an unrelated .git directory and provide a
> git revision unrelated to the FreeBSD source being built. For example,
> a build from my Subversion tree now reports "FreeBSD 12.0-CURRENT #2
> ad3f46a(master)" instead of "FreeBSD 12.0-CURRENT #5 r310482M".
>
> Can you explain your use case in a little more detail so that I can
> avoid breaking it with a change here? Do you commit FreeBSD snapshots
> into the "bigger project"?

This is done at work (Netflix). We import all the FreeBSD revisions
from github into our repo, and then merge them into the top level
FreeBSD directory from time to time using git's subtree functionality.
We also pull in our ports tree this way (so we have a ports directory
at the same level as our FreeBSD directory). So we don't have a
$TOPSRC/.git like you would if you'd just cloned directly from github.
Our .git directory lives in $TOPSRC/.git as a result. newvers.sh
should find the 'deepest' SCM it can, and use that instead of
apparently using the topmost (I'm surprised that you have FreeBSD
under a directory that has a git checkout in it, btw, but I know that
with my dotfile management repo, that sometimes happens by mistake).
And if this somehow produces a 'tie', the tie should go to svn.

Looking at how to fix this mess... woof. There's all kinds of crazy
here. Support for: git, git + svn, hg, p4, svn and svnlite. Sometimes
$VCS_cmd is defined if it exists at all on the system, other times
it's only defined if it exists on the system AND we think the tree is
under $VCS.

But the base of all this woe is that findvcs is called on a per-vcs
basis, rather than being called early to match one of N VCS
signatures. It would be better off searching each directory for each
file rather than finding any file at any level.

Warner