make overflow test on delta base offset work regardless of variable size
This patch introduces the MSB() macro to obtain the desired number of
most significant bits from a given variable independently of the variable
type.
It is then used to better implement the overflow test on the OBJ_OFS_DELTA
base offset variable with the property of always working correctly
regardless of the type/size of that variable.
Signed-off-by: Nicolas Pitre <nico@cam.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>
diff --git a/index-pack.c b/index-pack.c
index 3c768fb..0e54aa6 100644
--- a/index-pack.c
+++ b/index-pack.c
@@ -249,7 +249,7 @@
base_offset = c & 127;
while (c & 128) {
base_offset += 1;
- if (!base_offset || base_offset & ~(~0UL >> 7))
+ if (!base_offset || MSB(base_offset, 7))
bad_object(obj->offset, "offset value overflow for delta base object");
p = fill(1);
c = *p;
