[PATCH] Fixlets on top of Nico's clean-up.

[Junio C Hamano <junkio@cox.net>]

Do we care about a corner case where delta_size is not smaller
than 4 bytes, *datap passed to get_delta_hdr_size() points at
some bytes before a mmaped page boundary, and all the bytes til
the end of that page have high-bit set?  The said inline
function would step over the page boundary and would presumably
segfault/sigbus.

Other than that, with the attached patch on top of it, I find
your clean-up very pleasant to read.  Please consider it acked.

------------
If we prefer 0 as maxsize for diff_delta() to say "unlimited",
let's be consistent about it.

This patch also fixes type mismatch in a call to get_delta_hdr_size() 
from packed_delta_info().

Signed-off-by: Junio C Hamano <junkio@cox.net>
---

 diffcore-break.c |    2 +-
 sha1_file.c      |   11 ++++-------
 test-delta.c     |    2 +-
 3 files changed, 6 insertions(+), 9 deletions(-)

diff --git a/diffcore-break.c b/diffcore-break.c
--- a/diffcore-break.c
+++ b/diffcore-break.c
@@ -65,7 +65,7 @@ static int should_break(struct diff_file
 
 	delta = diff_delta(src->data, src->size,
 			   dst->data, dst->size,
-			   &delta_size, ~0UL);
+			   &delta_size, 0);
 
 	/* Estimate the edit size by interpreting delta. */
 	if (count_delta(delta, delta_size,
diff --git a/sha1_file.c b/sha1_file.c
--- a/sha1_file.c
+++ b/sha1_file.c
@@ -598,9 +598,9 @@ static int packed_delta_info(unsigned ch
 			     char *type,
 			     unsigned long *sizep)
 {
-	unsigned char *data;
+	const unsigned char *data;
 	unsigned char delta_head[64];
-	unsigned long data_size, result_size, base_size, verify_base_size;
+	unsigned long result_size, base_size, verify_base_size;
 	z_stream stream;
 	int st;
 
@@ -609,13 +609,10 @@ static int packed_delta_info(unsigned ch
 	if (sha1_object_info(base_sha1, type, &base_size))
 		die("cannot get info for delta-pack base");
 
-	data = base_sha1 + 20;
-	data_size = left - 20;
-
 	memset(&stream, 0, sizeof(stream));
 
-	stream.next_in = data;
-	stream.avail_in = data_size;
+	data = stream.next_in = base_sha1 + 20;
+	stream.avail_in = left - 20;
 	stream.next_out = delta_head;
 	stream.avail_out = sizeof(delta_head);
 
diff --git a/test-delta.c b/test-delta.c
--- a/test-delta.c
+++ b/test-delta.c
@@ -61,7 +61,7 @@ int main(int argc, char *argv[])
 	if (argv[1][1] == 'd')
 		out_buf = diff_delta(from_buf, from_size,
 				     data_buf, data_size,
-				     &out_size, ~0UL);
+				     &out_size, 0);
 	else
 		out_buf = patch_delta(from_buf, from_size,
 				      data_buf, data_size,
------------------------------------------------