Add better error reporting when listfile can't be found on disk

For Dumas Walker (CAPCITY2)

exec/addfiles.js

@@ -180,9 +180,16 @@ for(var d = 0; d < dir_list.length; d++) {
 
 	var listpath;
 	if(listfile) {
-		listpath = file_getcase(dir.path + listfile) || file_getcase(listfile);
-		var f = new File(listpath);
-		if(f.exists) {
+		if(file_getname(listfile) == listfile)
+			listpath = dir.path + listfile;
+		else
+			listpath = listfile;
+		var realpath = file_getcase(listpath);
+		if(!realpath) {
+			alert(listpath + " does not exist");
+			continue;
+		}
+		var f = new File(realpath);
 		writeln("Opening " + f.name);
 		if(!f.open('r')) {
 			alert("Error " + f.error + " (" + strerror(f.error) + ") opening " + f.name);
@@ -190,10 +197,6 @@ for(var d = 0; d < dir_list.length; d++) {
 		}
 		file_list = parse_file_list(f.readAll());
 		f.close();
-		} else {
-			alert(dir.path + file_getname(listfile) + " does not exist");
-			continue;
-		}
 	}
 	else {
 		var list = directory(dir.path + '*');