// Copyright 2016 chacha20-poly1305-aead Developers
//
// Licensed under the Apache License, Version 2.0, <LICENSE-APACHE or
// http://apache.org/licenses/LICENSE-2.0> or the MIT license <LICENSE-MIT or
// http://opensource.org/licenses/MIT>, at your option. This file may not be
// copied, modified, or distributed except according to those terms.

use std::mem;
use std::slice;

#[allow(clippy::missing_safety_doc)]
pub unsafe trait Safe {}

pub trait AsBytes {
    fn as_bytes(&self) -> &[u8];
    fn as_mut_bytes(&mut self) -> &mut [u8];
}

impl<T: Safe> AsBytes for [T] {
    #[inline]
    fn as_bytes(&self) -> &[u8] {
        unsafe {
            #[allow(clippy::manual_slice_size_calculation)]
            slice::from_raw_parts(self.as_ptr() as *const u8,
                                  self.len() * mem::size_of::<T>())
        }
    }

    #[inline]
    fn as_mut_bytes(&mut self) -> &mut [u8] {
        unsafe {
            #[allow(clippy::manual_slice_size_calculation)]
            slice::from_raw_parts_mut(self.as_mut_ptr() as *mut u8,
                                      self.len() * mem::size_of::<T>())
        }
    }
}

unsafe impl Safe for u8 {}

unsafe impl Safe for u16 {}

unsafe impl Safe for u32 {}

unsafe impl Safe for u64 {}

unsafe impl Safe for i8 {}

unsafe impl Safe for i16 {}

unsafe impl Safe for i32 {}

unsafe impl Safe for i64 {}