Re: Reading commit objects

From: Junio C Hamano <gitster@pobox.com>
Date: May 21, 2013, 22:20 UTC
Message-ID: <7v4ndwm0u8.fsf@alter.siamese.dyndns.org>
In-Reply-To: <CABx5MBQ57-=MPamvV-peZUdD_KDLX+5cy9vD7CL7p_Vz9BkvTg@mail.gmail.com>

Chico Sokol <chico.sokol@gmail.com> writes:

Show 7 quoted lines

> Hello,
>
> I'm building a library to manipulate git repositories (interacting
> directly with the filesystem).
>
> Currently, we're trying to parse commit objects. After decompressing
> the contents of a commit object file we got the following output:

Who wrote this commit object you are trying to read? Us, or your library (this question is to see if you are chasing the right problem)?

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> commit 191
> author Francisco Sokol <chico.sokol@gmail.com> 1369140112 -0300
> committer Francisco Sokol <chico.sokol@gmail.com> 1369140112 -0300
>
> first commit
>
> We hoped to get the same output of a "git cat-file -p <sha1>", but
> that didn't happened. From a commit object, how can I find tree object
> hash of this commit?

If you care about the byte-for-byte compatibility, never use "cat-file -p". That is meant for human consumption.

"git cat-file commit <sha1>" gives you the raw representation after inflating and stripping out the first "<type> SP <length> LF" line.