Re: [PATCH] denser delta header encoding

Linus, please do not apply this as is.

There are code other than what Nico updated with this patch in sha1_file.c that also need updating, that count the number of bytes in the delta-patch result by reading from the delta header.

I wonder if we can have a helper function in delta suite somewhere (maybe in diff-delta.c):

    int look_at_delta_header(void **delta_data, ulong delta_size,
    	                     ulong *src_size, ulong *dst_size)

that:

    - checks delta size and barf if it is small;
    - reads the header and fills src_size and dst_size;
    - advances *delta_data pointer;

and have count-delta, patch-delta and sha1_file.c users use it consistently. Nico, what do you think?