Configure how cheadergen generates C/C++ headers from Rust.

cheadergen generates C/C++ header files from Rust libraries that expose a pub extern "C" API. Output is controlled in two complementary ways:

• cheadergen.toml — a project-wide TOML file that the CLI loads via --config. It sets the preamble, include guards, sort order, per-package opaque/skip rules, per-header overrides, and language-specific options. See the config reference for the full schema.
• Per-item attributes — #[cheadergen::config(...)] on items and #[cheadergen(...)] on fields and variants, placed in your Rust source to control how an individual definition appears in the generated header. See the [config] macro for the directive reference.

Per-item attributes

There are two attribute levels:

• #[cheadergen::config(...)] — placed on items (structs, enums, unions, functions, statics, type aliases) to control their header representation.
• #[cheadergen(...)] — placed on fields and enum variants to control their individual representation within a parent item.

Example

#[cheadergen::config(export, rename = "CColor")]
#[repr(C)]
pub enum Color {
    #[cheadergen(rename = "COLOR_RED")]
    Red,
    Green,
    Blue,
}

#[cheadergen::config(export, field_names(x, y))]
#[repr(C)]
pub struct Point2D(pub f64, pub f64);

#[cheadergen::config(skip)]
#[unsafe(no_mangle)]
pub extern "C" fn internal_helper() {}