Thanks @foone https://digipres.club/@foone/112045597251087750

structcompile.py

# structcompile.py
# Joshua Scarsbrook (@[email protected])
# Very horrible code.
# License: Apache-2.0

import argparse
import pycparser  # Install with pip install pycparser

ast = pycparser.c_parser.c_ast


class BuiltinType:
    def __init__(self, format):
        self.format = format


def decl_to_python_struct(globals, decl) -> str:
    if type(decl) == BuiltinType:
        return decl.format

    typ = decl.type
    if type(typ) == ast.IdentifierType:
        name = " ".join(typ.names)
        return decl_to_python_struct(globals, globals[name])
    else:
        raise NotImplementedError(type(typ))


def struct_to_python_struct(globals, struct) -> str:
    if type(struct) != ast.Struct:
        raise Exception("struct is not a Struct")

    ret = "@"

    for decl in struct.decls:
        typ = decl.type
        if type(typ) == ast.ArrayDecl:
            array_format = decl_to_python_struct(globals, typ.type)
            dim = typ.dim
            if type(dim) == ast.Constant:
                if dim.type == "int":
                    ret += dim.value + array_format
            else:
                raise NotImplementedError(type(dim))
        elif type(typ) == ast.TypeDecl:
            ret += decl_to_python_struct(globals, typ)
        else:
            raise NotImplementedError(type(typ))

    return ret


if __name__ == "__main__":
    parser = argparse.ArgumentParser(
        prog="structcompile.py",
    )

    parser.add_argument(
        "filename",
        help="the file to include to find the structure. Unless --use-cpp is used this file must be preprocessed already.",
    )
    parser.add_argument("struct_name", help="the name of the struct to find")
    parser.add_argument(
        "--use-cpp",
        action="store_true",
        help="run the cpp preprocessor. filename will be looked up in the default include path.",
    )

    args = parser.parse_args()

    parsed = None

    if args.use_cpp:
        with open("tmp.c", "w") as f:
            f.write(f"#include <{args.filename}>")

        parsed = pycparser.parse_file("tmp.c", use_cpp=True)
    else:
        parsed = pycparser.parse_file(args.filename)

    decls = {}

    decls["unsigned char"] = BuiltinType("B")
    decls["unsigned short"] = BuiltinType("H")
    decls["unsigned int"] = BuiltinType("I")

    for node in parsed:
        if type(node) == ast.Typedef:
            decls[node.name] = node.type
            if node.name == args.struct_name:
                print(struct_to_python_struct(decls, node.type.type))