[PATCH] Define constants for lengths of object names

["brian m. carlson" <sandals@crustytoothpaste.net>]

Using preprocessor constants rather than hardcoded numbers is considered a
good programming practice.  Provide two constants, GIT_OID_RAWSZ and
GIT_OID_HEXSZ, which are the lengths of an SHA-1 object name in bytes and
hex digits, respectively.  These names are the same as those used by
libgit2.

Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
---
 object.h | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/object.h b/object.h
index 6e12f2c..f1cff2d 100644
--- a/object.h
+++ b/object.h
@@ -1,6 +1,13 @@
 #ifndef OBJECT_H
 #define OBJECT_H
 
+/*
+ * The length in bytes and in hex digits of an object name (SHA-1 value).
+ * These are the same names used by libgit2.
+ */
+#define GIT_OID_RAWSZ 20
+#define GIT_OID_HEXSZ 40
+
 struct object_list {
 	struct object *item;
 	struct object_list *next;
@@ -49,7 +56,7 @@ struct object {
 	unsigned used : 1;
 	unsigned type : TYPE_BITS;
 	unsigned flags : FLAG_BITS;
-	unsigned char sha1[20];
+	unsigned char sha1[GIT_OID_RAWSZ];
 };
 
 extern const char *typename(unsigned int type);
-- 
2.0.0.rc0