libreauth 0.18.1

use crate::get_slice_mut;
use crate::key::KeyBuilder;

/// [C binding] Generate a random key.
///
/// # Parameters
///
/// - `buff`: pointer to the buffer that will be filled with the random key
/// - `buff_len`: length of the buffer, in bytes
///
/// # Return code
///
/// 0 in case of success, 1 if anything failed.
///
/// ## Examples
/// ```c
/// char key[DEFAULT_KEY_SIZE + 1] = {0};
/// int32_t ret = libreauth_keygen(key, DEFAULT_KEY_SIZE);
/// if (ret != EXIT_SUCCESS) {
///     // Handle the error.
/// }
/// ```
///
/// # Safety
///
/// This function is a C binding and is therefore unsafe. It is not meant to be used in Rust.
#[unsafe(no_mangle)]
pub unsafe extern "C" fn libreauth_keygen(buff: *mut u8, buff_len: libc::size_t) -> i32 {
	let key_size = buff_len;
	if key_size == 0 || buff.is_null() {
		return 1;
	};
	let key = get_slice_mut!(buff, key_size);
	let out = KeyBuilder::new().size(key_size).generate().as_vec();
	let len = out.len();
	key[..len].clone_from_slice(&out[..len]);
	0
}