/// <summary>
/// Returns a newly allocated Segment in "Real Mode" memory
/// </summary>
/// <returns></returns>
public IntPtr16 AllocateRealModeSegment(ushort segmentSize = ushort.MaxValue)
{
_currentRealModePointer.Segment++;
var realModeSegment = new IntPtr16(_currentRealModePointer);
AddSegment(realModeSegment.Segment, segmentSize);
return(realModeSegment);
}
public MemoryCore()
{
_variablePointerDictionary = new Dictionary <string, IntPtr16>();
_currentVariablePointer = new IntPtr16(VARIABLE_BASE_SEGMENT, 0);
_currentRealModePointer = new IntPtr16(REALMODE_BASE_SEGMENT, 0);
_bigMemoryBlocks = new PointerDictionary <Dictionary <ushort, IntPtr16> >();
//Add Segment 0 by default, stack segment
AddSegment(0);
}
/// <summary>
/// Deletes all defined Segments from Memory
/// </summary>
public void Clear()
{
Array.Clear(_memorySegments, 0, _memorySegments.Length);
Array.Clear(_segments, 0, _segments.Length);
Array.Clear(_decompiledSegments, 0, _decompiledSegments.Length);
_variablePointerDictionary.Clear();
_currentVariablePointer = new IntPtr16(VARIABLE_BASE_SEGMENT, 0);
_currentRealModePointer = new IntPtr16(REALMODE_BASE_SEGMENT, 0);
_bigMemoryBlocks.Clear();
}
/// <summary>
/// Safe retrieval of a pointer to a defined variable
///
/// Returns false if the variable isn't defined
/// </summary>
/// <param name="name"></param>
/// <param name="pointer"></param>
/// <returns></returns>
public bool TryGetVariablePointer(string name, out IntPtr16 pointer)
{
if (!_variablePointerDictionary.TryGetValue(name, out var result))
{
pointer = null;
return(false);
}
pointer = result;
return(true);
}
public MemoryCore()
{
_memorySegments = new Dictionary <ushort, byte[]>();
_segments = new Dictionary <ushort, Segment>();
_decompiledSegments = new Dictionary <ushort, Dictionary <ushort, Instruction> >();
_variablePointerDictionary = new Dictionary <string, IntPtr16>();
_currentVariablePointer = new IntPtr16(VARIABLE_BASE, 0);
_bigMemoryBlocks = new PointerDictionary <Dictionary <ushort, IntPtr16> >();
//Add Segment 0 by default, stack segment
AddSegment(0);
}
/// <summary>
/// Allocates the specified variable name with the desired size
/// </summary>
/// <param name="name"></param>
/// <param name="size"></param>
/// <param name="declarePointer"></param>
/// <returns></returns>
public IntPtr16 AllocateVariable(string name, ushort size, bool declarePointer = false)
{
if (!string.IsNullOrEmpty(name) && _variablePointerDictionary.ContainsKey(name))
{
_logger.Warn($"Attmped to re-allocate variable: {name}");
return(_variablePointerDictionary[name]);
}
//Do we have enough room in the current segment?
//If not, declare a new segment and start there
if (size + _currentVariablePointer.Offset >= ushort.MaxValue)
{
_currentVariablePointer.Segment++;
_currentVariablePointer.Offset = 0;
AddSegment(_currentVariablePointer.Segment);
}
if (!HasSegment(_currentVariablePointer.Segment))
{
AddSegment(_currentVariablePointer.Segment);
}
#if DEBUG
_logger.Debug(
$"Variable {name ?? "NULL"} allocated {size} bytes of memory in Host Memory Segment {_currentVariablePointer.Segment:X4}:{_currentVariablePointer.Offset:X4}");
#endif
var currentOffset = _currentVariablePointer.Offset;
_currentVariablePointer.Offset += (ushort)(size + 1);
var newPointer = new IntPtr16(_currentVariablePointer.Segment, currentOffset);
if (declarePointer && string.IsNullOrEmpty(name))
{
throw new Exception("Unsupported operation, declaring pointer type for NULL named variable");
}
if (!string.IsNullOrEmpty(name))
{
_variablePointerDictionary[name] = newPointer;
if (declarePointer)
{
var variablePointer = AllocateVariable($"*{name}", 0x4, false);
SetArray(variablePointer, newPointer.ToSpan());
}
}
return(newPointer);
}
/// <summary> /// Returns the specified block by index in the desired memory block /// </summary> /// <param name="block"></param> /// <param name="index"></param> /// <returns></returns> public IntPtr16 GetBigMemoryBlock(IntPtr16 block, ushort index) => _bigMemoryBlocks[block.Offset][index];
/// <summary> /// Returns an array containing the cstring stored at the specified pointer /// </summary> /// <param name="pointer"></param> /// <param name="stripNull"></param> /// <returns></returns> public ReadOnlySpan <byte> GetString(IntPtr16 pointer, bool stripNull = false) => GetString(pointer.Segment, pointer.Offset, stripNull);
/// <summary> /// Sets the specified pointer value at the desired segment:offset /// </summary> /// <param name="segment"></param> /// <param name="offset"></param> /// <param name="value"></param> public void SetPointer(ushort segment, ushort offset, IntPtr16 value) => SetArray(segment, offset, value.Data);
/// <summary>
/// Zeroes out the memory at the specified pointer for the desired number of bytes
/// </summary>
/// <param name="pointer"></param>
/// <param name="length"></param>
public void SetZero(IntPtr16 pointer, int length)
{
var destinationSpan = new Span <byte>(_memorySegments[pointer.Segment], pointer.Offset, length);
destinationSpan.Fill(0);
}
/// <summary> /// Sets the specified pointer value at the desired pointer /// </summary> /// <param name="pointer"></param> /// <param name="value"></param> public void SetPointer(IntPtr16 pointer, IntPtr16 value) => SetArray(pointer, value.Data);
/// <summary> /// Sets the specified pointer value at the defined variable /// </summary> /// <param name="variableName"></param> /// <param name="value"></param> public void SetPointer(string variableName, IntPtr16 value) => SetArray(GetVariablePointer(variableName), value.Data);
/// <summary> /// Sets the specified word at the desired pointer /// </summary> /// <param name="pointer"></param> /// <param name="value"></param> public void SetWord(IntPtr16 pointer, ushort value) => SetWord(pointer.Segment, pointer.Offset, value);
/// <summary> /// Sets the specified array at the desired pointer /// </summary> /// <param name="pointer"></param> /// <param name="array"></param> public void SetArray(IntPtr16 pointer, ReadOnlySpan <byte> array) => SetArray(pointer.Segment, pointer.Offset, array);
/// <summary> /// Sets the specified byte at the desired pointer /// </summary> /// <param name="pointer"></param> /// <param name="value"></param> public void SetByte(IntPtr16 pointer, byte value) => SetByte(pointer.Segment, pointer.Offset, value);
/// <summary> /// Returns a single byte from the specified pointer /// </summary> /// <param name="pointer"></param> /// <returns></returns> public byte GetByte(IntPtr16 pointer) => GetByte(pointer.Segment, pointer.Offset);
/// <summary> /// Returns an array with desired count from the specified pointer /// </summary> /// <param name="pointer"></param> /// <param name="count"></param> /// <returns></returns> public ReadOnlySpan <byte> GetArray(IntPtr16 pointer, ushort count) => GetArray(pointer.Segment, pointer.Offset, count);
/// <summary> /// Returns an unsigned word from the specified pointer /// </summary> /// <param name="pointer"></param> /// <returns></returns> public ushort GetWord(IntPtr16 pointer) => GetWord(pointer.Segment, pointer.Offset);
/// <summary> /// Returns a pointer stored at the specified pointer /// </summary> /// <param name="pointer"></param> /// <returns></returns> public IntPtr16 GetPointer(IntPtr16 pointer) => new IntPtr16(GetArray(pointer, 4));
