bytemaker

What is it?

bytemaker is a Python 3.8-compatible zero-dependency library for byte serialization/deserialization. It brings C bitfield functionality over to Python version 3.8+. To that end, it provides methods and types for converting @dataclass-decorated classes.

What can you do with it?

bytemaker gives you the following:

• A Bits class analogous to Python's bytes and bytearray classes, but for sub-byte bit quantities. Bits readily supports conversion from and to both, as well as lists and bit/octet/hex strings.
• A set of ytypes classes, including various-sized Bit classes, various-sized Byte classes, common C types (U8, U16, U32, U64, S8, S16..., and Float16, Float32, Float64), and factories to create these and chararrays to arbitrary bitcounts. All of these can be instantiated from their respective types, derive from Bits (and thus can be instantiated in the same way Bits objects can), and can be cast into each other in additional ways as needed.
• Support for serializing/deserializing @dataclass annotated classes, where the annotations can be ytypes, Python ctypes (c_uint8, ctypes.STRUCTURE, etc.), or Python native types pytypes (int, bool, char, float). Nested types? No problem!
• Automagic support for handling any of the aforementioned objects via aggregate_types.to_bits_aggregate and aggregate_types.from_bits_aggregate.

How do I install it?

Run python -m pip install bytemaker.

Project intent

The main goal of the project is to ease development of projects working with compiled code (e.g. ROM hacking). As such, streaming features are currently deemphasized, although I may implement them at some later date.

Errata

At present, bytemaker assumes big-endianness (à la N64). Full support for reading from and writing to little-endian ROMs will come very soon. ctypes support currently assumes development is done on a little-endian machine. This is the vast, vast, vast majority of consumer hardware today, unless you run a bi-endian machine and have set it to big-endian mode.