tomolib 1.1.1

Library for reading, modifying, and extracting Tomodachi Life data formats.
Documentation 
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const fn make_table() -> [u32; 256] {
    let mut table = [0u32; 256];
    let mut i: u32 = 0;
    while i < 256 {
        let mut c = i;
        let mut k = 0;
        while k < 8 {
            c = if c & 1 != 0 {
                0xEDB8_8320 ^ (c >> 1)
            } else {
                c >> 1
            };
            k += 1;
        }
        table[i as usize] = c;
        i += 1;
    }
    table
}

static TABLE: [u32; 256] = make_table();

#[must_use]
pub(crate) fn crc32(data: &[u8]) -> u32 {
    let mut c = 0xFFFF_FFFFu32;
    for &b in data {
        c = TABLE[((c ^ u32::from(b)) & 0xFF) as usize] ^ (c >> 8);
    }
    c ^ 0xFFFF_FFFF
}

#[cfg(test)]
mod tests {
    use super::*;

    #[test]
    fn empty_is_zero() {
        assert_eq!(crc32(b""), 0);
    }

    #[test]
    fn check_value() {
        assert_eq!(crc32(b"123456789"), 0xCBF4_3926);
    }

    #[test]
    fn known_name_matches_bars_table() {
        assert_eq!(crc32(b"SE_GuitarAC_E_Rtm02_BPM120"), 0x0016_4298);
    }
}