+dir_name (char const *path)
+{
+ size_t length = dir_len (path);
+ int append_dot = (length == FILESYSTEM_PREFIX_LEN (path));
+ char *newpath = xmalloc (length + append_dot + 1);
+ memcpy (newpath, path, length);
+ if (append_dot)
+ newpath[length++] = '.';
+ newpath[length] = 0;
+ return newpath;
+}
+
+#ifdef TEST_DIRNAME
+/*
+
+Run the test like this (expect no output):
+ gcc -DHAVE_CONFIG_H -DTEST_DIRNAME -I.. -O -Wall \
+ basename.c dirname.c xmalloc.c
+ sed -n '/^BEGIN-DATA$/,/^END-DATA$/p' dirname.c|grep -v DATA|./a.out
+
+BEGIN-DATA
+foo//// .
+bar/foo//// bar
+foo/ .
+/ /
+. .
+a .
+END-DATA
+
+*/
+
+# define MAX_BUFF_LEN 1024
+# include <stdio.h>
+
+int
+main ()