public static byte[] Decompress(ArraySlice <byte> data, int offset = 0)
{
switch (data[offset] & 0xFF)
{
case 0x10:
return(Decompress10Lz(data, offset));
case 0x11:
return(Decompress11Lz(data, offset));
default:
return(null);
}
}
public static void ApplyPatch(ArraySlice <byte> rom, byte[] patch)
{
var patchlen = patch.Length;
if (patchlen < 8 ||
patch[0] != 'P' ||
patch[1] != 'A' ||
patch[2] != 'T' ||
patch[3] != 'C' ||
patch[4] != 'H')
{
throw new IOException("not a valid IPS file");
}
var offset = 5;
while (offset + 2 < patchlen)
{
var writeOffset = ReadIpsOffset(patch, offset);
if (writeOffset == 0x454f46)
{
return;
}
offset += 3;
if (offset + 1 >= patchlen)
{
throw new IOException("abrupt ending to IPS file, entry cut off before size");
}
var size = ReadIpsSize(patch, offset);
offset += 2;
if (size == 0)
{
if (offset + 1 >= patchlen)
{
throw new IOException("abrupt ending to IPS file, entry cut off before RLE size");
}
var rleSize = ReadIpsSize(patch, offset);
if (writeOffset + rleSize > rom.Length)
{
throw new IOException("trying to patch data past the end of the ROM file");
}
offset += 2;
if (offset >= patchlen)
{
throw new IOException("abrupt ending to IPS file, entry cut off before RLE byte");
}
var rleByte = patch[offset++];
for (var i = writeOffset; i < writeOffset + rleSize; i++)
{
rom[i] = rleByte;
}
}
else
{
if (offset + size > patchlen)
{
throw new IOException("abrupt ending to IPS file, entry cut off before end of data block");
}
if (writeOffset + size > rom.Length)
{
throw new IOException("trying to patch data past the end of the ROM file");
}
ArraySlice.Copy(patch, offset, rom, writeOffset, size);
offset += size;
}
}
throw new IOException("improperly terminated IPS file");
}
public ArraySlice(ArraySlice <T> slice, int length, int offset = 0)
: this(slice.Pointer, length, offset + slice.Offset)
{
}
public ArraySlice(ArraySlice <T> slice)
: this(slice.Pointer)
{
}