[PATCH 0/4] git-diff: use mode for tree:name syntax (was: Re: [PATCH 2/7] gitweb: Support comparing blobs with different names)

From: Martin Koegler <mkoegler@auto.tuwien.ac.at>
Date: Apr 21, 2007, 12:23 UTC
Message-ID: <20070421122348.GA29174@auto.tuwien.ac.at>
In-Reply-To: <200704202249.08464.jnareb@gmail.com>

On Fri, Apr 20, 2007 at 10:49:08PM +0200, Jakub Narebski wrote:

> So from me it is slight Nak to this patch, at least unless "git diff 
> <tree1>:<path1> <tree2>:<path2>" will take the information about file 
> name and mode (permissions) from <tree1> and <tree2>, and included such 
> information in extended git diff header.

I created a prototyp implemention:

* Patch 1:
 add a parameter to get_sha1 to store the mode, if it is known.
 If it is not possible to dermine the mode, it stores S_IFINVALID.

* Patch 2:
 add space for the mode in object_array (unknown mode is S_IFINVALID).

* Patch 3:
 stores the mode for <tree>:<filename> syntax

* Patch 4:
 use mode information for comparing two blobs

The patches are large, as some heavy used functions get a new parameter. The changes should not increase the CPU time. Patch 2 increases the storage size for each object of object_array by an unsigned for the mode.

My blobdiff patch will need some small adaptations:
* we need to add --raw -p --full-index as diff arguments
* we must pass $hash_parent_base.':'.$file_parent and
  $hash_base.':'.$file_name to git-diff instead of 
  $hash and $hash_parent, if possible.

mfg Martin Kögler