// SPDX-License-Identifier: GPL-2.0 //! Foreign function interface (FFI) types. //! //! This crate provides mapping from C primitive types to Rust ones. //! //! The Rust [`core`] crate provides [`core::ffi`], which maps integer types to the platform default //! C ABI. The kernel does not use [`core::ffi`], so it can customise the mapping that deviates from //! the platform default. #![no_std] macro_rules! alias { ($($name:ident = $ty:ty;)*) => {$( #[allow(non_camel_case_types, missing_docs)] pub type $name = $ty; // Check size compatibility with `core`. const _: () = assert!( core::mem::size_of::<$name>() == core::mem::size_of::<core::ffi::$name>() ); )*} } alias! { // `core::ffi::c_char` is either `i8` or `u8` depending on architecture. In the kernel, we use // `-funsigned-char` so it's always mapped to `u8`. c_char = u8; c_schar = i8; c_uchar = u8; c_short = i16; c_ushort = u16; c_int = i32; c_uint = u32; // In the kernel, `intptr_t` is defined to be `long` in all platforms, so we can map the type to // `isize`. c_long = isize; c_ulong = usize; c_longlong = i64; c_ulonglong = u64; } pub use core::ffi::c_void;