Goal: Fix FTBFS on Hurd because PATH-MAX is undefined

Fix: #372155

Author: Michael Banck  <mbanck@debian.org>

Status wrt upstream: should be forwarded

Index: shadow-4.1.0/lib/commonio.c
===================================================================
--- shadow-4.1.0.orig/lib/commonio.c
+++ shadow-4.1.0/lib/commonio.c
@@ -50,17 +50,31 @@
 int lrename (const char *old, const char *new)
 {
 
+#ifdef PATH_MAX
 	char resolved_path[PATH_MAX];
+#endif
+	char *r;
 	int res;
 
 #if defined(S_ISLNK)
 	struct stat sb;
 	if (lstat (new, &sb) == 0 && S_ISLNK (sb.st_mode)) {
-		if (realpath (new, resolved_path) == NULL) {
+#ifndef PATH_MAX
+		r = realpath (new, NULL);
+#else
+		r = realpath (new, resolved_path);
+#endif
+		if (r == NULL) {
+#ifndef PATH_MAX
+			free (r);
+#endif
 			perror ("realpath in lrename()");
 		} else {
-			new = resolved_path;
+			new = r;
 		}
+#ifndef PATH_MAX
+	free (r);
+#endif
 	}
 #endif
 	res = rename (old, new);