Add a test case for trim_trailing_slashes, and make it handle other cases.

syscall.c

@@ -113,15 +113,19 @@ int do_rename(char *fname1, char *fname2)
 
 void trim_trailing_slashes(char *name)
 {
-	char *p;
+	int l;
 	/* Some BSD systems cannot make a directory if the name
 	 * contains a trailing slash.
 	 * <http://www.opensource.apple.com/bugs/X/BSD%20Kernel/2734739.html> */
-	if (!*name)
-		return;		/* empty string */
-	p = strchr(name, '\0') - 1;
-	while (p == '/') {
-		p-- = '\0';
+	
+	/* Don't change empty string; and also we can't improve on
+	 * "/" */
+	
+	l = strlen(name);
+	while (l > 1) {
+		if (name[--l] != '/')
+			break;
+		name[l] = '\0';
 	}
 }