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, 3 insertions, 2 deletions

diff --git a/sha1_file.c b/sha1_file.c
index f2d33afb27..5464828259 100644
--- a/sha1_file.c
+++ b/sha1_file.c
@@ -108,9 +108,10 @@ int safe_create_leading_directories(char *path)
 
 char * sha1_to_hex(const unsigned char *sha1)
 {
-	static char buffer[50];
+	static int bufno;
+	static char hexbuffer[4][50];
 	static const char hex[] = "0123456789abcdef";
-	char *buf = buffer;
+	char *buffer = hexbuffer[3 & ++bufno], *buf = buffer;
 	int i;
 
 	for (i = 0; i < 20; i++) {