Re: Index format v5

From: Philip Oakley <philipoakley@iee.org>
Date: May 4, 2012, 13:25 UTC
Message-ID: <2A6D903A618147EEBBFEF99234104EE6@PhilipOakley>
In-Reply-To: <CALgYhfMKdbv8TiT4ALDSvD3pSXHEPLWHM09DxYnRmRdBWRjh8Q@mail.gmail.com>

From: "Thomas Gummerer" <t.gummerer@gmail.com> Sent: Thursday, May 03, 2012 
6:25 PM

Show 16 quoted lines

>I have been drafting the Version 5 of the index format over the past
> few days with the help of Thomas Rast, Michael Haggerty, cmn and
> barrbrain on IRC. It will save with prefix compression on the path, and
> using a crc32 over the stat data, instead of the full data, since it is 
> only
> used for checking if the file is changed. (Thanks Michael Haggerty for
> this hint. Unless we are missing something this will save another
> ~4 MB on the Webkit index.
>
>
>
> GIT index format
> ================
>
> = The git index file has the following format
>

xxx

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>
> == Directory entry
>
>  Directory entries are sorted in lexicographic order by the name
>  of their path starting with the root.
>
>  Path names (variable length) relative to top level directory (without the
>    leading slash). '/' is used as path separator. '.' indicates the root
>    directory. The special patch components ".." and ".git" (without 
> quotes)
>    are disallowed. Trailing slash is also disallowed.
>

Does the prohibition of ".git" prevent the potential for versioning of the .git directory itself (e.g. .gitignore the pack & objects themselves)?

It should be possible for one's current repo status to be tracked and summarised by a single sha1, say as an indepenedent branch, as you would the code itself.

[my use case is in a managed environment where one has plenty of networked project storage, but no real availability of a network server, so anybody and his mate could corrupt ones network repo with badly thought through tweaks. The lack of a server is the root cause, but that's not something the project can fix, so thinks ... 'version the meta data...']

I can see that the lack of the leading "/", and the ".." are a policy statement about paths being relative to top level directory, with direct path referencing. The typical avoidance of ".git" should be a note about how regular git works, rather than an absolute prohibition.

Philip