rust-cmacros

Rust library to assist with parsing and translating #define macro definitions from C header files to corresponding Rust code for use with bindings to external libraries.

Update: Vojtech Kral suggested a much better idea - Generate C++ code which leverages the compiler's type inference to determine the types of macros: http://vojtech.kral.hk/en/rust-importing-c-constants-proof-of-concept/

Intro

To use libraries with a C interface from Rust, rust-bindgen can be used to generate Rust bindings automatically. It does not translate constants or functions defined as macros in C headers to Rust code however.

rust-cmacros is a simple and fairly dumb library which helps to fill this gap.

It has two basic functions:

• extract_macros() parses the source of a C header file and extracts C macro definitions
• generate_rust_src() takes as input a set of extracted macros and a translator function and generates Rust code.

Examples

cargo run --example parse_all_headers /usr/include

Parse all headers in /usr/include and print re-constructed #define statements

cargo run --example translate_macros /usr/include/sqlite3.h

Parse /usr/include/sqlite3.h and output translations of the macros using the default translation function. In real usage, you would supply a translation function to skip or modify the translations for non-trivial or unnecessary macros.