internal static Token Synchronize(HashSet<TokenType> types, Scanner scanner, MessageProducer mp)
{
Token tok = scanner.CurrentToken;
// if the current token is not in the synchronization set
// then it is unexpected and the parser must recover.
if (!types.Contains(tok.TokenType))
{
// flag the unexpected token
ErrorHandler.Flag(tok, ErrorCode.UNEXPECTED_TOKEN, mp);
// recover by skipping tokens that are not in
// the synchronization set.
do
{
tok = scanner.GetNextToken();
} while (!tok.IsEof && !types.Contains(tok.TokenType));
}
return tok;
}
public static AssignmentStatementParser CreateWithObservers(Scanner s, SymbolTableStack stack, List<IMessageObserver> obl)
{
return NonTerminalParser.CreateWithObserver<AssignmentStatementParser>(s, stack, obl);
}
static void Main(string[] args)
{
bool show_help = false;
bool xref = false;
bool print_ast = false;
string action = "compile";
var names = new List<string>();
var p = new OptionSet()
{
{ "h|help", "show this message and exit", v => show_help = v != null },
{ "x|xref", "perform a cross-reference of identifiers", v => xref = v != null },
{ "i|intermediate", "print the parse tree of the input", v => print_ast = v != null },
{ "a|action=", "`compile' or `interpret' the input", v => action = v },
};
List<string> extra;
try
{
extra = p.Parse(args);
}
catch (OptionException option_exception)
{
Console.Write("dradis: ");
Console.WriteLine(option_exception.Message);
Console.WriteLine("Try `dradis --help' for more information.");
return;
}
if (show_help)
{
ShowHelp(p);
return;
}
if (extra.Count == 0)
{
Console.WriteLine("dradis: ");
Console.WriteLine("No source file given.");
Console.WriteLine("Try `dradis --help' for more information.");
return;
}
string source_path = extra[0];
try
{
using (StreamReader reader = new StreamReader(source_path))
{
SourceMessageObserver sourceObserver = new SourceMessageObserver();
Source source = new Source(reader);
source.Add(sourceObserver);
Scanner scanner = new Scanner(source);
Parser parser = new Parser(scanner);
ParserMessageObserver parserObserver = new ParserMessageObserver();
parser.Add(parserObserver);
var result = parser.Parse();
if (parser.ErrorCount > 0)
{
ICode icode = result.Item1;
SymbolTableStack symtabstack = result.Item2;
if (xref)
{
XRef.Print(symtabstack);
}
if (print_ast)
{
ParseTreePrinter printer = new ParseTreePrinter(Console.Out);
printer.Print(icode);
}
Backend backend = Backend.Create(action);
if (backend == null)
{
throw new Exception("`action' can be either `compile' or 'interpret'!");
}
backend.Add(new BackendMessageObserver());
backend.Process(icode, symtabstack);
}
}
} catch(Exception ex)
{
Console.WriteLine("dradis: ");
Console.WriteLine("FATAL ERROR: " + ex.Message);
Console.WriteLine("TRACE: " + ex.StackTrace);
}
}
public static ExpressionParser CreateWithObservers(Scanner s, SymbolTableStack stack, List<IMessageObserver> obl)
{
return NonTerminalParser.CreateWithObserver<ExpressionParser>(s, stack, obl);
}
public Parser(Scanner s)
{
scanner = s;
}