Teach getdirname() to return "." as appropriate.

1 files changed, 9 insertions, 5 deletions

diff --git a/lib/lib.c b/lib/lib.c
index fe402af8..f98f00a5 100644
--- a/lib/lib.c
+++ b/lib/lib.c
@@ -1005,14 +1005,18 @@ void mode_to_string(mode_t mode, char *buf)
 }
 
 // dirname() can modify its argument or return a pointer to a constant string
-// This always returns a malloc() copy of everyting before last (run of ) '/'.
+// This returns a malloc() copy of everyting before last (run of ) '/',
+// or "." if no path.
 char *getdirname(char *name)
 {
-  char *s = xstrdup(name), *ss = strrchr(s, '/');
+  char *s, *ss, *keep;
 
-  while (ss && *ss && *ss == '/' && s != ss) *ss-- = 0;
-
-  return s;
+  for (s = name, ss = keep = 0; ; s++) {
+    if (!*s) return keep ? xstrndup(name, keep-name) : xstrdup(".");
+    if (*s != '/') keep = ss;
+    else if (s == name) keep = ss = s+1;
+    else if (s[-1] != '/') ss = s;
+  }
 }
 
 // basename() can modify its argument or return a pointer to a constant string