/// <summary>
/// Loads a collection of chunks from a Quetzal file.
/// </summary>
/// <param name="stream">The stream to read from.</param>
/// <returns>A new <see cref="Quetzal"/> instance initialized
/// from the stream.</returns>
/// <remarks>
/// Duplicate chunks are not supported by this class. Only the last
/// chunk of a given type will be available.
/// </remarks>
public static Quetzal FromStream(Stream stream)
{
Quetzal result = new Quetzal();
uint type = BigEndian.ReadInt32(stream);
if (type != FORM && type != LIST && type != CAT_)
{
throw new ArgumentException("Invalid IFF type");
}
int length = (int)BigEndian.ReadInt32(stream);
byte[] buffer = new byte[length];
int amountRead = stream.Read(buffer, 0, (int)length);
if (amountRead < length)
{
throw new ArgumentException("Quetzal file is too short");
}
stream = new MemoryStream(buffer);
type = BigEndian.ReadInt32(stream);
if (type != IFZS)
{
throw new ArgumentException("Wrong IFF sub-type: not a Quetzal file");
}
while (stream.Position < stream.Length)
{
type = BigEndian.ReadInt32(stream);
length = (int)BigEndian.ReadInt32(stream);
byte[] chunk = new byte[length];
amountRead = stream.Read(chunk, 0, length);
if (amountRead < length)
{
throw new ArgumentException("Chunk extends past end of file");
}
result.chunks[type] = chunk;
}
return(result);
}
private void SaveToStream(Stream stream, uint destType, uint destAddr)
{
if (stream == null)
{
return;
}
Quetzal quetzal = new Quetzal();
// 'IFhd' identifies the first 128 bytes of the game file
quetzal["IFhd"] = image.GetOriginalIFHD();
// 'CMem' or 'UMem' are the compressed/uncompressed contents of RAM
byte[] origRam = image.GetOriginalRAM();
byte[] newRomRam = image.GetMemory();
int ramSize = (int)(image.EndMem - image.RamStart);
#if !SAVE_UNCOMPRESSED
quetzal["CMem"] = Quetzal.CompressMemory(
origRam, 0, origRam.Length,
newRomRam, (int)image.RamStart, ramSize);
#else
byte[] umem = new byte[ramSize + 4];
BigEndian.WriteInt32(umem, 0, (uint)ramSize);
Array.Copy(newRomRam, (int)image.RamStart, umem, 4, ramSize);
quetzal["UMem"] = umem;
#endif
// 'Stks' is the contents of the stack, with a stub on top
// identifying the destination of the save opcode.
PushCallStub(new CallStub(destType, destAddr, pc, fp));
byte[] trimmed = new byte[sp];
Array.Copy(stack, trimmed, (int)sp);
quetzal["Stks"] = trimmed;
PopCallStub();
// 'MAll' is the list of heap blocks
if (heap != null)
quetzal["MAll"] = heap.Save();
else
{
}
quetzal.WriteToStream(stream);
}
/// <summary>
/// Loads a collection of chunks from a Quetzal file.
/// </summary>
/// <param name="stream">The stream to read from.</param>
/// <returns>A new <see cref="Quetzal"/> instance initialized
/// from the stream.</returns>
/// <remarks>
/// Duplicate chunks are not supported by this class. Only the last
/// chunk of a given type will be available.
/// </remarks>
public static Quetzal FromStream(Stream stream)
{
Quetzal result = new Quetzal();
uint type = BigEndian.ReadInt32(stream);
if (type != FORM && type != LIST && type != CAT_)
throw new ArgumentException("Invalid IFF type");
int length = (int)BigEndian.ReadInt32(stream);
byte[] buffer = new byte[length];
int amountRead = stream.Read(buffer, 0, (int)length);
if (amountRead < length)
throw new ArgumentException("Quetzal file is too short");
stream = new MemoryStream(buffer);
type = BigEndian.ReadInt32(stream);
if (type != IFZS)
throw new ArgumentException("Wrong IFF sub-type: not a Quetzal file");
while (stream.Position < stream.Length)
{
type = BigEndian.ReadInt32(stream);
length = (int)BigEndian.ReadInt32(stream);
byte[] chunk = new byte[length];
amountRead = stream.Read(chunk, 0, length);
if (amountRead < length)
throw new ArgumentException("Chunk extends past end of file");
result.chunks[type] = chunk;
}
return result;
}
