Re: parsecvs tool now creates git repositories

From: Junio C Hamano <junkio@cox.net>
Date: Apr 4, 2006, 06:09 UTC
Message-ID: <7vodzhc1oh.fsf@assigned-by-dhcp.cox.net>
In-Reply-To: <1144122709.2303.153.camel@neko.keithp.com>

Keith Packard <keithp@keithp.com> writes:

Show 5 quoted lines

> I've just changed parsecvs to generate blobs for every revision in
> each ,v file right after they're read in; putting the necessary code
> right into parsecvs should be reasonably straightforward; we don't need
> the multi-patch logic as we do want to compute each intermediate version
> of the file.

If you want to go really fast without extra fork, are writing it in C, and have the data for blob in core, you could link with libgit.a and call write_sha1_file() yourself:

	unsigned char sha1[20];
        void *buf;
        unsigned long len;

	write_sha1_file(buf, len, "blob", sha1);

instead of forking "hash-object -w". You feed your blob data in buf, with its length in len, and you will get the blob object name back in sha1[]. buf is owned by you and after write_sha1_file() returns it is safe for you to scribble over it or free() it. sha1[] stores binary object name (20 bytes, not 40-byte hexadecimal), and you can use the helper function sha1_to_hex() if you need a hex representation:

	char *sha1_to_hex(sha1)

which returns a pointer to a static buffer that is valid until next call to sha1_to_hex(), so you need to strdup it if you want to retain it.