[PATCH 1/2] sha1_name: try to use same abbrev length when core.abbrevguard is specified

[Namhyung Kim <namhyung@gmail.com>]

If find_unique_abbrev() finds a ambiguous SHA1 name, it tries
to find again with increased length. In this case, result hex
strings could have different lengths even though the
core.abbrevguard config option is specified. But if the option
is specified and increased length (delta) is less than its
value, the result could be adjusted to the same length.

Signed-off-by: Namhyung Kim <namhyung@gmail.com>
---
 sha1_name.c |    5 ++++-
 1 files changed, 4 insertions(+), 1 deletions(-)

diff --git a/sha1_name.c b/sha1_name.c
index 709ff2e..6bb8942 100644
--- a/sha1_name.c
+++ b/sha1_name.c
@@ -197,6 +197,7 @@ const char *find_unique_abbrev(const unsigned char *sha1, int len)
 {
 	int status, exists;
 	static char hex[41];
+	int extra_len = unique_abbrev_extra_length;
 
 	exists = has_sha1_file(sha1);
 	memcpy(hex, sha1_to_hex(sha1), 40);
@@ -208,12 +209,14 @@ const char *find_unique_abbrev(const unsigned char *sha1, int len)
 		if (exists
 		    ? !status
 		    : status == SHORT_NAME_NOT_FOUND) {
-			int cut_at = len + unique_abbrev_extra_length;
+			int cut_at = len + extra_len;
 			cut_at = (cut_at < 40) ? cut_at : 40;
 			hex[cut_at] = 0;
 			return hex;
 		}
 		len++;
+		if (extra_len > 0)
+			extra_len--;
 	}
 	return hex;
 }
-- 
1.7.4