Make fsck-cache warn about old-style tree objects that have full

pathnames in them. We're migrating away from that.

This will cause tons of warnings for the current "sparse" archive,
but hell, better now than later.

fsck-cache.c

@@ -20,13 +20,22 @@ static int mark_sha1_seen(unsigned char *sha1, char *tag)
 
 static int fsck_tree(unsigned char *sha1, void *data, unsigned long size)
 {
+	int warn_old_tree = 1;
+
 	while (size) {
 		int len = 1+strlen(data);
 		unsigned char *file_sha1 = data + len;
 		char *path = strchr(data, ' ');
 		unsigned int mode;
 		if (size < len + 20 || !path || sscanf(data, "%o", &mode) != 1)
 			return -1;
+
+		/* Warn about trees that don't do the recursive thing.. */
+		if (warn_old_tree && strchr(path, '/')) {
+			fprintf(stderr, "warning: fsck-cache: tree %s has full pathnames in it\n", sha1_to_hex(sha1));
+			warn_old_tree = 0;
+		}
+
 		data += len + 20;
 		size -= len + 20;
 		mark_needs_sha1(sha1, S_ISDIR(mode) ? "tree" : "blob", file_sha1);