public IScript Compile(String scriptCode, String name)
{
Stack stack = new Stack();
//System.Diagnostics.Debugger.Launch();
XDocument script = XDocument.Parse(scriptCode.Trim());
m_entryPoint = -1;
m_currentProgramCode = new MemoryStream();
m_parameterSequence = new ParameterSequence();
XElement root = script.Element("Root");
if (root == null)
{
root = script.Element("root");
if (root == null)
{
throw new Exception("Error. Script must contain a root node.");
}
}
foreach (XElement node in root.Elements())
{
bool isMain = false;
if (node.Name.LocalName == "Main" || node.Name.LocalName == "main")
{
// scripts starts here
m_entryPoint = (int)m_currentProgramCode.Position;
// push all attributes to the parameter sequencer (so the script can run with default parameters)
ParameterSequenceBuilder sequenceBuilder = new ParameterSequenceBuilder();
sequenceBuilder.createSequence();
foreach (XAttribute attr in node.Attributes())
{
sequenceBuilder.addParameter(new StringParameter(attr.Name.ToString(), attr.Value));
}
m_parameterSequence = sequenceBuilder.CurrentSequence;
stack = new Stack(m_parameterSequence.getMemStream());
isMain = true;
}
// add node as a function
else
{
//m_dataTable.Data.Add(node.Name.LocalName, (int)m_currentProgramCode.Position);
m_functionTable.add(node.Name.LocalName, (int)m_currentProgramCode.Position);
isMain = false;
}
compileRoutine(node, isMain,stack);
}
// end of program
m_currentProgramCode.Writer.Write((int)XmlScriptExecutor.OpCode.HALT);
XmlScriptCompiled compiledScript = new XmlScriptCompiled(scriptCode);
compiledScript.Name = name;
compiledScript.ProgramCode = m_currentProgramCode;
compiledScript.EntryPoint = m_entryPoint;
compiledScript.ParameterSequence = m_parameterSequence;
if (m_entryPoint == -1)
{
throw new Exception("Error no entrypoint for script: " + name);
}
return compiledScript;
}
public Stack(MemoryStream data)
{
m_data = data;
}
private void serializeData(XmlDocument doc, XmlElement data, AbstractElement element)
{
XnaScrapCore.Core.MemoryStream memoryStream = new XnaScrapCore.Core.MemoryStream();
XnaScrapCore.Core.StringWriter sw = new XnaScrapCore.Core.StringWriter(memoryStream);
element.doSerialize(sw);
// stream is now filled with string
long end = memoryStream.Position;
memoryStream.Position = 0;
while (memoryStream.Position < end)
{
XmlElement value = doc.CreateElement("Value");
value.InnerXml = memoryStream.Reader.ReadString();
data.AppendChild(value);
}
}
private String readNextProgramString(MemoryStream programCode)
{
programCode.Position = m_eip;
String ret = programCode.Reader.ReadString();
m_eip += ret.Length+1;
return ret;
}
private int readNextProgramInt(MemoryStream programCode)
{
programCode.Position = m_eip;
m_eip += sizeof(int);
return programCode.Reader.ReadInt32();
}
private float readNextProgramFloat(MemoryStream programCode)
{
programCode.Position = m_eip;
m_eip += sizeof(float);
return programCode.Reader.ReadSingle();
}
private OpCode readNextOpCode(MemoryStream programCode)
{
programCode.Position = m_eip;
m_eip += sizeof(int);
m_opcode = (OpCode)programCode.Reader.ReadInt32();
return m_opcode;
}
/// <summary>
/// Executes a subroutine. All parameters must be written to the heap before execution.
/// Afterwards the addresses of the parameters have to be stored in the stack (realtive to stackpointer).
/// Mind this if you want to execute a script with external parameters.
/// </summary>
/// <param name="programCode">The script's code.</param>
/// <param name="data">The data stack of the current script execution.</param>
public void executeSub(MemoryStream programCode, int entryPoint, Stack data, Heap heap)
{
m_eip = entryPoint;
m_ebp = (int)data.Position; // base pointer
readNextOpCode(programCode);
while (m_opcode != OpCode.HALT)
{
//eip = (int)programCode.Position;
switch (m_opcode)
{
case OpCode.POP_INT:
{
break;
}
case OpCode.POP_FLOAT:
{
break;
}
case OpCode.POP_STRING:
{
break;
}
case OpCode.PUSH_INT:
{
data.push(readNextProgramInt(programCode));
break;
}
case OpCode.PUSH_FLOAT:
{
data.push(readNextProgramFloat(programCode));
break;
}
case OpCode.PUSH_STRING:
{
data.push(readNextProgramString(programCode));
break;
}
case OpCode.PUSH_ADDR:
{
int addr = readNextProgramInt(programCode); // address relative to ebp
// read heap address from stack
int heapAddr = data.readInt(m_ebp + addr);
data.push(heapAddr);
break;
}
case OpCode.PUSH_EBP:
{
data.push(m_ebp);
break;
}
case OpCode.ADD_INT:
{
int val1 = data.popInt();
int val2 = data.popInt();
data.push(val1 + val2);
break;
}
case OpCode.SUB_INT:
{
int val1 = data.popInt();
int val2 = data.popInt();
data.push(val1 - val2);
break;
}
case OpCode.READ_INT:
{
int addr = data.popInt();
data.push(data.readInt(addr));
break;
}
case OpCode.WRITE_INT:
{
// read address
int addr = data.popInt();
// read value
int value = data.popInt();
// write
data.writeInt(addr,value);
break;
}
case OpCode.READ_FLOAT:
{
int addr = data.popInt();
data.push(data.readFlt(addr));
break;
}
case OpCode.WRITE_FLOAT:
{
// read address
int addr = data.popInt();
// read value
float value = data.popInt();
// write
data.writeFlt(addr, value);
break;
}
case OpCode.ALLOC_STRING_ON_HEAP:
{
String s = data.popString();
int address = heap.allocString(s);
data.push(address);
break;
}
case OpCode.READ_STRING_FROM_HEAP:
{
//int ptr = data.readInt((int)data.Position + addr * sizeof(int));
int ptr = data.popInt();
String s = heap.readString(ptr);
data.push(s);
break;
}
case OpCode.BEGIN_BLOCK:
{
// save base pointer
m_ebp = (int)data.Position;
data.push(m_ebp);
break;
}
case OpCode.CALL_FUNCTION:
{
// get function address
int func_addr = data.popInt();
// save instruction pointer
data.push(m_eip);
m_eip = func_addr;
programCode.Position = m_eip;
break;
}
case OpCode.RETURN:
{
m_eip = data.popInt(); // restore eip
programCode.Position = m_eip;
break;
}
case OpCode.END_BLOCK:
{
m_ebp = data.popInt(); // restore ebp
data.set(m_ebp);
break;
}
// Built in function
case OpCode.NATIVE_CALL:
{
int f = readNextProgramInt(programCode);
if (f > 0)
{
m_registeredFunctions.RegisteredFunctionAddresses[f].execute(data,heap);
}
else if (f < 0)
{
m_registeredFunctions.RegisteredFunctionAddresses[-1*f].end(data,heap);
}
break;
}
}
readNextOpCode(programCode);
}
}
