blob: d0555f81f1cacea19de9bf365fef9d70ebb4fe9e [file] [log] [blame]
// Copyright 2015-2016 Brian Smith.
//
// Permission to use, copy, modify, and/or distribute this software for any
// purpose with or without fee is hereby granted, provided that the above
// copyright notice and this permission notice appear in all copies.
//
// THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHORS DISCLAIM ALL WARRANTIES
// WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
// MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY
// SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
// WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
// OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
// CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
//! Polyfills for functionality that will (hopefully) be added to Rust's
//! standard library soon.
use core;
#[macro_use]
pub mod convert;
#[inline(always)]
pub const fn u64_from_usize(x: usize) -> u64 { x as u64 }
#[inline(always)]
pub fn usize_from_u32(x: u32) -> usize { x as usize }
/// `core::num::Wrapping` doesn't support `rotate_left`.
/// There is no usable trait for `rotate_left`, so this polyfill just
/// hard-codes u32. https://github.com/rust-lang/rust/issues/32463
#[inline(always)]
pub fn wrapping_rotate_left_u32(x: core::num::Wrapping<u32>, n: u32) -> core::num::Wrapping<u32> {
core::num::Wrapping(x.0.rotate_left(n))
}
pub mod slice {
#[inline(always)]
pub fn u32_from_be_u8(buffer: [u8; 4]) -> u32 {
u32::from(buffer[0]) << 24
| u32::from(buffer[1]) << 16
| u32::from(buffer[2]) << 8
| u32::from(buffer[3])
}
#[inline(always)]
pub fn be_u8_from_u32(value: u32) -> [u8; 4] {
[
((value >> 24) & 0xff) as u8,
((value >> 16) & 0xff) as u8,
((value >> 8) & 0xff) as u8,
(value & 0xff) as u8,
]
}
// https://github.com/rust-lang/rust/issues/27750
// https://internals.rust-lang.org/t/stabilizing-basic-functions-on-arrays-and-slices/2868
#[inline(always)]
pub fn fill(dest: &mut [u8], value: u8) {
for d in dest {
*d = value;
}
}
}