1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30
// This file is part of Substrate. // Copyright (C) 2020-2021 Parity Technologies (UK) Ltd. // SPDX-License-Identifier: GPL-3.0-or-later WITH Classpath-exception-2.0 // This program is free software: you can redistribute it and/or modify // it under the terms of the GNU General Public License as published by // the Free Software Foundation, either version 3 of the License, or // (at your option) any later version. // This program is distributed in the hope that it will be useful, // but WITHOUT ANY WARRANTY; without even the implied warranty of // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the // GNU General Public License for more details. // You should have received a copy of the GNU General Public License // along with this program. If not, see <https://www.gnu.org/licenses/>. use std::ops::Range; /// Construct a range from an offset to a data length after the offset. /// Returns None if the end of the range would exceed some maximum offset. pub fn checked_range(offset: usize, len: usize, max: usize) -> Option<Range<usize>> { let end = offset.checked_add(len)?; if end <= max { Some(offset..end) } else { None } }