static void AssembleStrings(SourceLine line)
{
if (!line.OperandHasToken)
{
throw new ExpressionException(line.Instruction.Position,
$"Instruction \"{line.InstructionName}\" expects one or more string arguments.");
}
line.Assembly = new List <byte>();
var stringBytes = new List <byte>();
var uninit = 0;
foreach (Token child in line.Operand.Children)
{
if (child.Children.Count == 0)
{
throw new ExpressionException(child.Position, $"Expected value for instruction \"{line.InstructionName}\".");
}
if (child.Children[0].ToString().Equals("?"))
{
if (child.Children.Count > 1)
{
Assembler.Log.LogEntry(line, child.Children[1].Position,
$"Unexpected expression \"{child.Children[1].Name}\".");
}
uninit++;
Assembler.Output.AddUninitialized(1);
}
else
{
if (StringHelper.ExpressionIsAString(child))
{
stringBytes.AddRange(Assembler.Encoding.GetBytes(StringHelper.GetString(child)));
}
else
{
stringBytes.AddRange(BinaryOutput.ConvertToBytes(Evaluator.Evaluate(child)).ToList());
}
}
}
switch (line.InstructionName)
{
case ".cstring":
stringBytes.Add(0x00);
break;
case ".pstring":
if (stringBytes.Count > 255)
{
throw new ExpressionException(line.Operand.Position, $"String expression exceeds the maximum length of \".pstring\" directive.");
}
stringBytes.Insert(0, Convert.ToByte(stringBytes.Count));
break;
case ".lstring":
case ".nstring":
if (stringBytes.Any(b => b > 0x7f))
{
throw new ExpressionException(line.Operand.Position, $"One or more elements in expression \"{line.Operand}\" exceeds maximum value.");
}
if (line.InstructionName.Equals(".lstring"))
{
stringBytes = stringBytes.Select(b => Convert.ToByte(b << 1)).ToList();
stringBytes[^ 1] |= 1;