ffi-convert

Convert between idiomatic Rust values and C-compatible data structures with a minimum of unsafe ceremony.

ffi-convert provides two conversion traits — CReprOf (Rust → C) and AsRust (C → Rust) — plus CDrop and RawPointerConverter to handle ownership of pointer fields, and derive macros that take care of the boilerplate.

use ffi_convert::{AsRust, CDrop, CReprOf};
use std::ffi::{c_char, c_float};

pub struct Pizza {
    pub name: String,
    pub weight: f32,
}

#[repr(C)]
#[derive(CReprOf, AsRust, CDrop)]
#[target_type(Pizza)]
pub struct CPizza {
    pub name: *const c_char,
    pub weight: c_float,
}

let pizza = Pizza { name: "Margarita".to_owned(), weight: 450.0 };
let c_pizza = CPizza::c_repr_of(pizza).unwrap();        // Rust -> C
let again: Pizza = c_pizza.as_rust().unwrap();          // C    -> Rust

Workspace layout

Full documentation lives on docs.rs/ffi-convert, including the type-mapping table, attribute reference, and caveats that apply to the derives.

More on open source projects at Sonos here.

License

Licensed under either of

• Apache License, Version 2.0 (LICENSE-APACHE or http://www.apache.org/licenses/LICENSE-2.0)
• MIT license (LICENSE-MIT or http://opensource.org/licenses/MIT)

at your option.

Contribution

Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the work by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.