hidparser 1.0.3

HID report descriptor parsing library
Documentation 
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//! Parser Utility Functions
//!
//! This module contains utility functions used to do conversions of variable length byte slices into integer types.
//!
//! ## License
//!
//! Copyright (C) Microsoft Corporation. All rights reserved.
//!
//! SPDX-License-Identifier: BSD-2-Clause-Patent
//!
pub fn u16_from_bytes(bytes: &[u8]) -> u16 {
    if bytes.is_empty() {
        return 0;
    }
    let mut u16_bytes = [0_u8; 2];
    u16_bytes[..bytes.len()].clone_from_slice(bytes);
    u16::from_le_bytes(u16_bytes)
}

pub fn u32_from_bytes(bytes: &[u8]) -> u32 {
    if bytes.is_empty() {
        return 0;
    }
    let mut u32_bytes = [0_u8; 4];
    u32_bytes[..bytes.len()].clone_from_slice(bytes);
    u32::from_le_bytes(u32_bytes)
}

pub fn i32_from_bytes(bytes: &[u8]) -> i32 {
    if bytes.is_empty() {
        return 0;
    }
    let mut i32_bytes = [0_u8; 4];
    //sign-extend
    if (bytes.last().unwrap() & 0x80) != 0 {
        i32_bytes.fill(0xff);
    }
    i32_bytes[..bytes.len()].clone_from_slice(bytes);
    i32::from_le_bytes(i32_bytes)
}