starnix_uapi/
math.rs

1// Copyright 2023 The Fuchsia Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style license that can be
3// found in the LICENSE file.
4
5use super::errors::{Errno, errno};
6
7pub fn round_up_to_increment<N, M>(size: N, increment: M) -> Result<N, Errno>
8where
9    N: TryInto<u64>,
10    N: TryFrom<u64>,
11    M: TryInto<u64>,
12{
13    let size: u64 = size.try_into().map_err(|_| errno!(EINVAL))?;
14    let increment: u64 = increment.try_into().map_err(|_| errno!(EINVAL))?;
15    let spare = size % increment;
16    let result = if spare > 0 {
17        size.checked_add(increment - spare).ok_or_else(|| errno!(EINVAL))?
18    } else {
19        size
20    };
21    N::try_from(result).map_err(|_| errno!(EINVAL))
22}
23
24pub fn round_down_to_increment<N, M>(size: N, increment: M) -> Result<N, Errno>
25where
26    N: TryInto<u64>,
27    N: TryFrom<u64>,
28    M: TryInto<u64>,
29{
30    let size: u64 = size.try_into().map_err(|_| errno!(EINVAL))?;
31    let increment: u64 = increment.try_into().map_err(|_| errno!(EINVAL))?;
32    let result = size - (size % increment);
33    N::try_from(result).map_err(|_| errno!(EINVAL))
34}
starnix_uapi/math.rs

starnix_uapi/
math.rs
