public static int UnpackStringAddress(byte[] memory, ushort byteAddress)
{
var version = Header.ReadVersion(memory);
switch (version)
{
case 1:
case 2:
case 3:
return(byteAddress * 2);
case 4:
case 5:
return(byteAddress * 4);
case 6:
case 7:
var stringsOffset = Header.ReadStringsOffset(memory);
return((byteAddress * 4) + (stringsOffset * 8));
case 8:
return(byteAddress * 8);
default:
throw new InvalidOperationException("Invalid version number: " + version);
}
}
public static int ReadFileSize(byte[] memory)
{
var fileSize = memory.ReadWord(FileSizeIndex);
var version = Header.ReadVersion(memory);
switch (version)
{
case 1:
case 2:
case 3:
return(fileSize * 2);
case 4:
case 5:
return(fileSize * 4);
case 6:
case 7:
case 8:
return(fileSize * 8);
default:
throw new InvalidOperationException("Invalid version number: " + version);
}
}
public static int ReadMainRoutineAddress(byte[] memory)
{
if (Header.ReadVersion(memory) == 6)
{
return(Header.UnpackRoutineAddress(memory, Header.ReadInitialPC(memory)));
}
else
{
return(Header.ReadInitialPC(memory) - 1);
}
}
public static void WriteFontWidthInUnits(byte[] memory, byte fontWidth)
{
if (Header.ReadVersion(memory) == 6)
{
memory.WriteByte(0x27, fontWidth);
}
else
{
memory.WriteByte(0x26, fontWidth);
}
}
private void AddAbbreviationRegions(byte[] memory)
{
var version = Header.ReadVersion(memory);
if (version == 1) // V1 did not support abbreviations
{
return;
}
var tableBase = Header.ReadAbbreviationsTableAddress(memory);
var count = version == 2 ? 32 : 96;
var tableEnd = tableBase + (count * 2) - 1;
AddRegion(MemoryMapRegionKind.AbbreviationPointerTable, "Abbreviation pointer table", tableBase, tableEnd);
var dataBase = 0;
var dataEnd = 0;
for (int i = 0; i < count; i++)
{
var address = memory.ReadWord(tableBase + (i * 2)) * 2;
if (dataBase == 0 || address < dataBase)
{
dataBase = address;
}
if (dataEnd == 0 || address > dataEnd)
{
dataEnd = address;
}
}
// scan last string in abbreviation data to get end...
while (true)
{
var zword = memory.ReadWord(dataEnd);
dataEnd += 2;
if ((zword & 0x8000) != 0)
{
break;
}
}
dataEnd--;
AddRegion(MemoryMapRegionKind.AbbreviationData, "Abbreviation data", dataBase, dataEnd);
}
private void AddObjectTableRegions(byte[] memory)
{
var objectTableBase = Header.ReadObjectTableAddress(memory);
var objectTableEnd = 0;
var objectDataBase = 0;
var objectDataEnd = 0;
var version = Header.ReadVersion(memory);
var entrySize = ObjectHelpers.GetEntrySize(version);
var propertyTableOffset = ObjectHelpers.GetPropertyTableAddressOffset(version);
int objectAddress = objectTableBase + ObjectHelpers.GetPropertyDefaultsTableSize(version);
while (objectDataBase == 0 || objectAddress < objectDataBase)
{
if (objectDataBase == 0 || objectAddress < objectDataBase)
{
var propertyTable = memory.ReadWord(objectAddress + propertyTableOffset);
if (objectDataBase == 0 || propertyTable < objectDataBase)
{
objectDataBase = propertyTable;
}
if (objectDataEnd == 0 || propertyTable > objectDataEnd)
{
objectDataEnd = propertyTable;
}
}
objectAddress += entrySize;
}
objectTableEnd = objectAddress - 1;
// skip last property table to get end...
var reader = new MemoryReader(memory, objectDataEnd);
reader.SkipShortName();
reader.SkipProperties(version);
objectDataEnd = reader.Address;
objectDataEnd--;
AddRegion(MemoryMapRegionKind.ObjectTable, "Object table", objectTableBase, objectTableEnd);
AddRegion(MemoryMapRegionKind.PropertyData, "Property data", objectDataBase, objectDataEnd);
}