From: Junio C Hamano <gitster@pobox.com>
Date: Sat, 23 Aug 2008 09:03:07 GMT
Subject: Re: [PATCH 1/5] Allow alternate "low-level" emit function from xdl_diff
Message-ID: <7vy72o14tw.fsf@gitster.siamese.dyndns.org>
In-Reply-To: <48AFC73F.2010100@lsrfire.ath.cx>

René Scharfe <rene.scharfe@lsrfire.ath.cx> writes:

> Could we move more code into the library code to avoid that ugliness?
>
> AFAICS, compare_buffer() builds a struct patch with an array of
> struct chunks, whose members are then fed one by one into either
> blame_chunk() or handle_split().  Could we avoid the allocation
> altogether by using a different interface?
>
> E.g. have a callback like this:
>
> 	static void handle_split_cb(long same, long p_next, long t_next,
> 			void *data)
> 	{
> 		struct chunk_cb_data *d = data;
> 		handle_split(d->sb, d->ent, d->tlno, d->plno, same,
> 				d->parent, d->split);
> 		d->plno = p_next;
> 		d->tlno = t_next;
> 	}
>
> And use it like this:
>
> 	struct chunk_cb_data d = {sb, ent, 0, 0, parent, split};
>         xpparam_t xpp;
>         xdemitconf_t xecfg;
>
>         xpp.flags = xdl_opts;
>         memset(&xecfg, 0, sizeof(xecfg));
>         xecfg.ctxlen = context;
> 	xdi_diff_chunks(file_p, file_o, &xpp, &xecfg, handle_split_cb, &d);
>         handle_split(sb, ent, d.tlno, d.plno, ent->num_lines,
> 			parent, split);
>
> Makes sense?

Absolutely; very well formulated.  Thanks.