/// <summary>
/// Adiciona um estado.
/// </summary>
/// <param name="index"></param>
/// <param name="fastate"></param>
private void AddDfaState(int index, FAState fastate)
{
if (!_initialized)
{
throw new ParserException("Table sizes not initialized");
}
_DfaStates[index] = fastate;
}
/// <summary>
/// Carrega as tabelas da gramática.
/// </summary>
/// <param name="reader"></param>
private void LoadTables(GrammarReader reader)
{
object obj;
int index;
while (reader.MoveNext())
{
byte id = (byte)reader.RetrieveNext();
switch ((RecordId)id)
{
case RecordId.Parameters:
_parameters["Name"] = (string)reader.RetrieveNext();
_parameters["Version"] = (string)reader.RetrieveNext();
_parameters["Author"] = (string)reader.RetrieveNext();
_parameters["About"] = (string)reader.RetrieveNext();
_caseSensitive = (bool)reader.RetrieveNext();
_startSymbol = (int)reader.RetrieveNext();
break;
case RecordId.TableCounts:
_symbols = new Symbol[(int)reader.RetrieveNext()];
_charsets = new String[(int)reader.RetrieveNext()];
_rules = new Rule[(int)reader.RetrieveNext()];
_DfaStates = new FAState[(int)reader.RetrieveNext()];
_LalrTables = new LRActionTable[(int)reader.RetrieveNext()];
_initialized = true;
break;
case RecordId.Initial:
_initDfaState = (int)reader.RetrieveNext();
_initLalrState = (int)reader.RetrieveNext();
break;
case RecordId.Symbols:
index = (int)reader.RetrieveNext();
var name = (string)reader.RetrieveNext();
var kind = (SymbolType)(int)reader.RetrieveNext();
var symbol = new Symbol(index, name, kind);
AddSymbol(symbol);
break;
case RecordId.CharSets:
index = (int)reader.RetrieveNext();
var charset = (string)reader.RetrieveNext();
AddCharset(index, charset);
break;
case RecordId.Rules:
index = (int)reader.RetrieveNext();
var head = _symbols[(int)reader.RetrieveNext()];
var rule = new Rule(index, head);
reader.RetrieveNext();
while ((obj = reader.RetrieveNext()) != null)
{
rule.AddItem(_symbols[(int)obj]);
}
AddRule(rule);
break;
case RecordId.DFAStates:
FAState fastate = new FAState();
index = (int)reader.RetrieveNext();
if ((bool)reader.RetrieveNext())
{
fastate.AcceptSymbol = (int)reader.RetrieveNext();
}
else
{
reader.RetrieveNext();
}
reader.RetrieveNext();
while (!reader.RetrieveDone())
{
var ci = (int)reader.RetrieveNext();
var ti = (int)reader.RetrieveNext();
reader.RetrieveNext();
fastate.AddEdge(_charsets[ci], ti);
}
AddDfaState(index, fastate);
break;
case RecordId.LRTables:
LRActionTable table = new LRActionTable();
index = (int)reader.RetrieveNext();
reader.RetrieveNext();
while (!reader.RetrieveDone())
{
var sid = (int)reader.RetrieveNext();
var action = (int)reader.RetrieveNext();
var tid = (int)reader.RetrieveNext();
reader.RetrieveNext();
table.AddItem(_symbols[sid], (Action)action, tid);
}
AddLalrTable(index, table);
break;
case RecordId.Comment:
Console.WriteLine("Comment record encountered");
break;
default:
throw new ParserException("Wrong id for record");
}
}
}
/// <summary>
/// Recupera um token.
/// </summary>
/// <returns></returns>
private Token RetrieveToken()
{
Token result;
int peekChar = -1;
int currentPos = 0;
int lastAcceptState = -1;
int lastAcceptPos = -1;
FAState currentState = _DfaStates[_initDfaState];
while (true)
{
int target = -1;
peekChar = _source.LookAhead(currentPos);
if (peekChar == -1)
{
break;
}
char ch = FixCase((char)peekChar);
foreach (FAEdge edge in currentState.Edges)
{
String chars = edge.Characters;
if (chars.IndexOf(ch) != -1)
{
target = edge.TargetIndex;
break;
}
}
if (target != -1)
{
if (_DfaStates[target].AcceptSymbol != -1)
{
lastAcceptState = target;
lastAcceptPos = currentPos;
}
currentState = _DfaStates[target];
currentPos++;
}
else
{
break;
}
}
if (lastAcceptState != -1)
{
Symbol symbol = _symbols[_DfaStates[lastAcceptState].AcceptSymbol];
result = new Token(symbol);
result.Data = _source.Read(lastAcceptPos + 1);
}
else
{
if (peekChar == -1)
{
result = new Token(_endSymbol);
result.Data = "";
}
else
{
result = new Token(_errorSymbol);
result.Data = _source.Read(1);
}
}
UpdateLineNumber((String)result.Data);
return(result);
}