public static async Task <GlulxMachine> CreateAsync(Stream stream)
{
var memory = await Memory.CreateAsync(stream);
var header = new GlulxHeader(memory);
VerifyChecksum(memory, header.Checksum);
// Initial the memory should have a size equal to ExtStart.
// We must expand it to EndMem.
if (header.ExtStart != memory.Size)
{
throw new InvalidOperationException($"Size expected to be {header.ExtStart}");
}
memory.Expand((int)header.EndMem);
memory.AddReadOnlyRegion(0, (int)header.RamStart);
if (header.StackSize % 256 != 0)
{
throw new InvalidOperationException("Stack size must be a multiple of 256");
}
var stack = new Stack((int)header.StackSize);
return(new GlulxMachine(header, memory, stack));
}
private GlulxMachine(GlulxHeader header, Memory memory, Stack stack) : base(memory, stack, (int)header.StartFunc)
{
this.Header = header;
}