bpx 3.1.0

// Copyright (c) 2021, BlockProject 3D
//
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//
// Redistribution and use in source and binary forms, with or without modification,
// are permitted provided that the following conditions are met:
//
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//       this list of conditions and the following disclaimer.
//     * Redistributions in binary form must reproduce the above copyright notice,
//       this list of conditions and the following disclaimer in the documentation
//       and/or other materials provided with the distribution.
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//       may be used to endorse or promote products derived from this software
//       without specific prior written permission.
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// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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// CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
// EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
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// PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
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use std::convert::TryInto;

pub trait GenericArrayLen
{
    const SIZE: usize;
    type TArray;

    fn from_array(buf: &[u8]) -> Self::TArray;
}

pub struct T3 {}

impl GenericArrayLen for T3
{
    type TArray = [u8; 3];
    const SIZE: usize = 3;

    fn from_array(buf: &[u8]) -> Self::TArray
    {
        return buf.try_into().unwrap();
    }
}

pub struct T16 {}

impl GenericArrayLen for T16
{
    type TArray = [u8; 16];
    const SIZE: usize = 16;

    fn from_array(buf: &[u8]) -> Self::TArray
    {
        return buf.try_into().unwrap();
    }
}

pub fn extract_slice<TArray: GenericArrayLen>(large_buf: &[u8], offset: usize) -> TArray::TArray
{
    let buf = &large_buf[offset..offset + TArray::SIZE];
    return TArray::from_array(buf);
}