Re: [PATCH 5/7] cleanups: Remove unused variable from sha1_file.c

From: Junio C Hamano <junkio@cox.net>
Date: Apr 17, 2006, 21:42 UTC
Message-ID: <7v64l7lw04.fsf@assigned-by-dhcp.cox.net>
In-Reply-To: <20060417151448.1D99C19B912@sergelap.hallyn.com>

"Serge E. Hallyn" <serue@us.ibm.com> writes:

> Left is assigned to, but never used in sha1_file.c

True, but in this case I suspect it should be used to make sure we have the 20-byte base_sha1 that follows the header in deltified case, perhaps like this:

diff --git a/sha1_file.c b/sha1_file.c
index e3d0113..929f481 100644
--- a/sha1_file.c
+++ b/sha1_file.c
@@ -874,17 +874,19 @@ void packed_object_info_detail(struct pa
 			       unsigned char *base_sha1)
 {
 	struct packed_git *p = e->p;
-	unsigned long offset, left;
+	unsigned long offset;
 	unsigned char *pack;
 	enum object_type kind;
 
 	offset = unpack_object_header(p, e->offset, &kind, size);
 	pack = p->pack_base + offset;
-	left = p->pack_size - offset;
 	if (kind != OBJ_DELTA)
 		*delta_chain_length = 0;
 	else {
 		unsigned int chain_length = 0;
+		if (p->pack_size - 20 < offset)
+			die("pack file %s records an incomplete delta base",
+			    p->pack_name);
 		memcpy(base_sha1, pack, 20);
 		do {
 			struct pack_entry base_ent;