Using the previous commit's inredirection mechanism for SHA1,
support a chunked implementation of SHA1_Update() that limits the
amount of data in the chunk passed to SHA1_Update().
This is enabled by using the Makefile variable SHA1_MAX_BLOCK_SIZE
to specify chunk size. When using Apple's CommonCrypto library this
is set to 1GiB (the implementation cannot handle more 4GiB).
Signed-off-by: Atousa Pahlevan Duprat <apahlevan@ieee.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
