Names, game IDs, patch lists, LBA ranges and hash exceptions are passed
as pointer plus count. min/max/fill/copy become ternaries, memset and
memcpy; FST entries sort with an in-place heap sort, partitions with an
insertion sort. WAD content checks decrypt and hash in 2 KiB chunks
straight from the borrowed input; banner names read onto the stack.
A deep-copy method CopyReader has been added to BlobReader (virtual) and all of its subclasses (override). This should create a second BlobReader to open the same set of data but with an independent read pointer so that it doesn't interfere with any reads done on the original Reader.
As part of this, IOFile has added code to create a deep copy IOFile pointer onto the same file, with code based on the platform in question to find the file ID from the file pointer and open a new one. There has also been a small piece added to FileInfo to enable a deep copy, but its only subclass at this time already had a copy constructor so this was relatively minor.