oid: Helper for old-school hashcmp

src/oid.h

@@ -9,17 +9,8 @@
 
 #include "git2/oid.h"
 
-/*
- * Compare two oid structures.
- *
- * @param a first oid structure.
- * @param b second oid structure.
- * @return <0, 0, >0 if a < b, a == b, a > b.
- */
-GIT_INLINE(int) git_oid__cmp(const git_oid *a, const git_oid *b)
+GIT_INLINE(int) git_oid__hashcmp(const unsigned char *sha1, const unsigned char *sha2)
 {
-	const unsigned char *sha1 = a->id;
-	const unsigned char *sha2 = b->id;
 	int i;
 
 	for (i = 0; i < GIT_OID_RAWSZ; i++, sha1++, sha2++) {
@@ -30,4 +21,16 @@ GIT_INLINE(int) git_oid__cmp(const git_oid *a, const git_oid *b)
 	return 0;
 }
 
+/*
+ * Compare two oid structures.
+ *
+ * @param a first oid structure.
+ * @param b second oid structure.
+ * @return <0, 0, >0 if a < b, a == b, a > b.
+ */
+GIT_INLINE(int) git_oid__cmp(const git_oid *a, const git_oid *b)
+{
+	return git_oid__hashcmp(a->id, b->id);
+}
+
 #endif

src/sha1_lookup.c

@@ -187,7 +187,7 @@ int sha1_position(const void *table,
 
 	do {
 		unsigned mi = (lo + hi) / 2;
-		int cmp = git_oid__cmp((git_oid *)(base + mi * stride), (git_oid *)key);
+		int cmp = git_oid__hashcmp(base + mi * stride, key);
 
 		if (!cmp)
 			return mi;