sha1_to_hex() usage cleanup

Somebody on the #git channel complained that the sha1_to_hex() thing uses
a static buffer which caused an error message to show the same hex output
twice instead of showing two different ones.

That's pretty easily rectified by making it uses a simple LRU of a few
buffers, which also allows some other users (that were aware of the buffer
re-use) to be written in a more straightforward manner.

Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>

1 files changed, 2 insertions, 4 deletions

diff --git a/diff.c b/diff.c
index 6762fcee5..c845c8711 100644
--- a/diff.c
+++ b/diff.c
@@ -1018,14 +1018,12 @@ static void run_diff(struct diff_filepair *p, struct diff_options *o)
 	}
 
 	if (memcmp(one->sha1, two->sha1, 20)) {
-		char one_sha1[41];
 		int abbrev = o->full_index ? 40 : DEFAULT_ABBREV;
-		memcpy(one_sha1, sha1_to_hex(one->sha1), 41);
 
 		len += snprintf(msg + len, sizeof(msg) - len,
 				"index %.*s..%.*s",
-				abbrev, one_sha1, abbrev,
-				sha1_to_hex(two->sha1));
+				abbrev, sha1_to_hex(one->sha1),
+				abbrev, sha1_to_hex(two->sha1));
 		if (one->mode == two->mode)
 			len += snprintf(msg + len, sizeof(msg) - len,
 					" %06o", one->mode);