Allow multiple "git_path()" uses

This allows you to maintain a few filesystem pathnames concurrently, by
simply replacing the single static "pathname" buffer with a LRU of four
buffers.

We did exactly the same thing with sha1_to_hex(), for pretty much exactly
the same reason. Sometimes you want to use two pathnames, and while it's
easy enough to xstrdup() them, why not just do the LU buffer thing.

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

path.c

@@ -13,9 +13,15 @@
 #include "cache.h"
 #include <pwd.h>
 
-static char pathname[PATH_MAX];
 static char bad_path[] = "/bad-path/";
 
+static char *get_pathname(void)
+{
+	static char pathname_array[4][PATH_MAX];
+	static int index;
+	return pathname_array[3 & ++index];
+}
+
 static char *cleanup_path(char *path)
 {
 	/* Clean it up */
@@ -31,6 +37,7 @@ char *mkpath(const char *fmt, ...)
 {
 	va_list args;
 	unsigned len;
+	char *pathname = get_pathname();
 
 	va_start(args, fmt);
 	len = vsnprintf(pathname, PATH_MAX, fmt, args);
@@ -43,6 +50,7 @@ char *mkpath(const char *fmt, ...)
 char *git_path(const char *fmt, ...)
 {
 	const char *git_dir = get_git_dir();
+	char *pathname = get_pathname();
 	va_list args;
 	unsigned len;