public BHeader(Stream stream)
{
// 4-byte Lua signature
if (stream.ReadInt32() != m_signature)
{
throw new InvalidOperationException("The input file does not have the signature of a valid Lua file.");
}
// 1-byte Lua version
var version = stream.ReadByte();
switch (version)
{
case 0x51:
Version = Version.LUA51;
break;
case 0x52:
Version = Version.LUA52;
break;
default:
{
var major = version >> 4;
var minor = version & 0x0F;
var error = System.String.Format("The input chunk's Lua version is {0}.{1}; unluac can only handle Lua 5.1 and Lua 5.2.",
major, minor);
throw new InvalidOperationException(error);
}
}
if (Debug)
{
Console.WriteLine("-- version: 0x{0:X}", version);
}
// 1-byte Lua "format"
var format = stream.ReadByte();
if (format != 0)
{
throw new InvalidOperationException("The input chunk reports a non-standard lua format: " + format);
}
if (Debug)
{
Console.WriteLine("-- format: {0}", format);
}
// 1-byte endianness
var endianness = stream.ReadByte();
if (endianness > 1)
{
throw new InvalidOperationException("The input chunk reports an invalid endianness: " + endianness);
}
BigEndian = (endianness == 0);
if (Debug)
{
Console.WriteLine("-- endianness: {0}", (BigEndian) ? "0 (big)" : "1 (little)");
}
// 1-byte int size
var intSize = stream.ReadByte();
if (Debug)
{
Console.WriteLine("-- int size: {0}", intSize);
}
Integer = new BIntegerType(intSize);
// 1-byte sizeT size
var sizeTSize = stream.ReadByte();
if (Debug)
{
Console.WriteLine("-- size_t size: {0}", sizeTSize);
}
SizeT = new BSizeTType(sizeTSize);
// 1-byte instruction size
var instructionSize = stream.ReadByte();
if (Debug)
{
Console.WriteLine("-- instruction size: {0}", instructionSize);
}
if (instructionSize != 4)
{
throw new InvalidOperationException("The input chunk reports an unsupported instruction size: " + instructionSize + " bytes");
}
var lNumberSize = stream.ReadByte();
if (Debug)
{
Console.WriteLine("-- Lua number size: {0}", lNumberSize);
}
var lNumberIntegralCode = stream.ReadByte();
if (Debug)
{
Console.WriteLine("-- Lua number integral code: {0}", lNumberIntegralCode);
}
if (lNumberIntegralCode > 1)
{
throw new InvalidOperationException("The input chunk reports an invalid code for lua number integralness: " + lNumberIntegralCode);
}
var lNumberIntegral = (lNumberIntegralCode == 1);
Number = new LNumberType(lNumberSize, lNumberIntegral);
Bool = new LBooleanType();
String = new LStringType();
Constant = new LConstantType();
Local = new LLocalType();
UpValue = new LUpvalueType();
Function = Version.GetLFunctionType();
if (Version.HasHeaderTail)
{
for (int i = 0; i < m_luacTail.Length; i++)
{
if (stream.ReadByte() != m_luacTail[i])
{
throw new InvalidOperationException("The input chunk does not have the header tail of a valid Lua file.");
}
}
}
}
public BSizeTType(int sizeTSize)
{
SizeTSize = sizeTSize;
m_integerType = new BIntegerType(sizeTSize);
}