Not 100% sure, but I think there is a small 'off by one' bug in IDHAMemoryXferBytes.cpp.

It's possible it is not causing issues - it all depends on what the calling code does with the class.

I think

pnum > numLeftInBuffer

should really be

pnum >= numLeftInBuffer

otherwise the routine does not flag EOF when we happen to request the exact number of remaining bytes.

See line with comment before it:
```
...
uint32 IDHAMemoryXferBytes::Read(void* buffer, uint32 pnum)

{
uint32 numToTransfer = 0;

do
{
    if (buffer == nil)
    {
        ASSERT_FAIL("buffer is nil!");
        break;
    }

    uint32 numLeftInBuffer = this->fCountBytesStored - this->fAbsolutePositionInBuffer;

    // SHOULD THIS NOT BE `pnum >= numLeftInBuffer`? 
            // If we exhaust the buffer exactly, we are also at EOF
    if (pnum > numLeftInBuffer) 
    {
        numToTransfer = numLeftInBuffer;
        fStreamState = kStreamStateEOF;
    }
    else
    {
        numToTransfer = pnum;
    }
    if (numToTransfer > 0)
        memcpy(buffer, fMyBuffer + fAbsolutePositionInBuffer, numToTransfer);

    fAbsolutePositionInBuffer += numToTransfer;

} while (false);
return numToTransfer;

}
...
```