The LibXDiff library implements basic and yet complete functionalities to
create file differences/patches to both binary and text files. The library
uses memory files as file abstraction to achieve both performance and
portability. For binary files, LibXDiff implements (with some modification)
the algorithm described in File System Support for Delta Compression by
Joshua P. MacDonald, while for text files it follows directives described in
An O(ND) Difference Algorithm and Its Variations by Eugene W. Myers. Memory
files used by the library are basically a collection of buffers that store the
file content. There are two different requirements for memory files when passed
to diff/patch functions. Text files for diff/patch functions require that a
single line do not have to spawn across two different memory file blocks.
Binary diff/patch functions require memory files to be compact. A compact
memory files is a file whose content is stored inside a single block.

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