/// <summary>
/// Creates a new instance of class PragmaScanner.
/// </summary>
/// <param name="file">The source file to scan.</param>
public PragmaScanner(string file, string grammarFile)
{
SourceFile = file;
pragmaGrammar = new Grammar();
pragmaGrammar.ReadGrammarFromFile(grammarFile);
parser = new Parser();
}
/// <summary>
/// Creates a new instance of class TasksPragmaScanner.
/// </summary>
/// <param name="file">The source file to scan.</param>
public TasksPragmaScanner(string file)
: base(file, grammarFile)
{
taskPragmaGrammar = new Grammar();
taskPragmaGrammar.ReadGrammarFromFile(@"Grammars\parallel_task_pragma_grammar.txt");
}
/// <summary>
/// Creates a new instance of class AtomicPragmaScanner.
/// </summary>
/// <param name="file">The source file to scan.</param>
public AtomicPragmaScanner(string file)
: base(file, grammarFile)
{
opGrammar = new Grammar();
opGrammar.ReadGrammarFromFile(@"Grammars\parallel_atomic_op_grammar.txt");
}
/// <summary>
/// Creates a new instance of class ForPragmaScanner.
/// </summary>
/// <param name="file">The source file to scan.</param>
public ForPragmaScanner(string file)
: base(file, grammarFile)
{
forInstructionGrammar = new Grammar();
forInstructionGrammar.ReadGrammarFromFile(@"Grammars\parallel_for_instruction_grammar.txt");
}
/// <summary>
/// Returns the production string used to obtain the given expression from the given grammar or
/// null if the expression cannot be obtained from the grammar.
/// </summary>
/// <param name="expression">The expression to validate.</param>
/// <param name="grammar">The given grammar.</param>
/// <returns>The production string.</returns>
public bool ValidateExpression(List<string> expression, Grammar grammar)
{
Configuration configuration = new Configuration();
configuration.ToBeConstructedStack.Push(grammar.StartingSymbol);
ParsingMoves currentMove = ParsingMoves.Expand;
string symbol;
string pop;
string temp;
bool exit = false;
do
{
evaluate:
// process the current move.
switch (currentMove)
{
case ParsingMoves.Expand:
pop = configuration.ToBeConstructedStack.Pop();
symbol = pop;
string productionApplied = symbol + "00";
configuration.ConstructedStack.Push(productionApplied);
for (int j = grammar.GetProductionsForSymbol(symbol)[0].RightSide.Count - 1; j >= 0; j--)
{
configuration.ToBeConstructedStack.Push(grammar.GetProductionsForSymbol(symbol)[0].RightSide[j]);
}
break;
case ParsingMoves.Advance:
pop = configuration.ToBeConstructedStack.Pop();
symbol = pop;
configuration.ConstructedStack.Push(symbol.ToString());
configuration.Index++;
break;
case ParsingMoves.MomentaryInsuccess:
configuration.State = States.Back;
if (grammar.Terminals.Contains(configuration.ConstructedStack.Peek()))
{
currentMove = ParsingMoves.Back;
}
else
{
currentMove = ParsingMoves.AnotherTry;
}
goto evaluate;
case ParsingMoves.Back:
if (configuration.ConstructedStack.Count == 0)
{
return false;
}
symbol = configuration.ConstructedStack.Pop();
configuration.ToBeConstructedStack.Push(symbol.ToString());
configuration.Index--;
temp = configuration.ConstructedStack.Peek();
int length = temp.Length;
if (length >= 3 && grammar.Nonterminals.Contains(temp.Substring(0, length - 2)))
{
currentMove = ParsingMoves.AnotherTry;
goto evaluate;
}
else
{
currentMove = ParsingMoves.Back;
goto evaluate;
}
case ParsingMoves.AnotherTry:
if (configuration.ConstructedStack.Count == 0)
{
return false;
}
temp = configuration.ConstructedStack.Pop();
string production = temp.Substring(0, temp.Length - 2);
int value = Int32.Parse(temp.Substring(temp.Length - 2));
int final = 0;
foreach (string str in grammar.GetProductionsForSymbol(production)[value].RightSide)
{
final += str.Length;
}
int total = 0;
while (total < final)
{
total += configuration.ToBeConstructedStack.Pop().Length;
}
if (value < grammar.GetProductionsForSymbol(production).Count - 1)
{
string newProduction = production;
if ((value + 1).ToString().Length == 1)
{
newProduction += "0" + (value + 1);
}
else
{
newProduction += (value + 1);
}
configuration.ConstructedStack.Push(newProduction);
for (int j = grammar.GetProductionsForSymbol(production)[value + 1].RightSide.Count - 1; j >= 0; j--)
{
configuration.ToBeConstructedStack.Push(grammar.GetProductionsForSymbol(production)[value + 1].RightSide[j]);
}
configuration.State = States.Normal;
}
else
{
configuration.ToBeConstructedStack.Push(production);
if (configuration.ConstructedStack.Count == 0)
{
return false;
}
string peek = configuration.ConstructedStack.Peek();
if (peek.Length >= 3 && grammar.Nonterminals.Contains(peek.Substring(0, peek.Length - 2)))
{
configuration.State = States.Normal;
currentMove = ParsingMoves.AnotherTry;
goto evaluate;
}
else
{
configuration.State = States.Back;
currentMove = ParsingMoves.Back;
goto evaluate;
}
}
break;
case ParsingMoves.Success:
configuration.State = States.Terminal;
exit = true;
break;
}
if (exit)
{
break;
}
if (expression.Count == configuration.Index)
{
if (configuration.ToBeConstructedStack.Count == 0)
{
currentMove = ParsingMoves.Success;
goto evaluate;
}
}
if (configuration.ToBeConstructedStack.Count == 0)
{
currentMove = ParsingMoves.MomentaryInsuccess;
goto evaluate;
}
else
{
// determine next move based on stack content.
string nextSymbol = configuration.ToBeConstructedStack.Peek();
if (grammar.Terminals.Contains(nextSymbol))
{
if (expression.Count <= configuration.Index || nextSymbol != expression[configuration.Index])
{
currentMove = ParsingMoves.MomentaryInsuccess;
}
else
{
currentMove = ParsingMoves.Advance;
}
}
else
{
currentMove = ParsingMoves.Expand;
}
}
}
while (true);
return true;
}