Function decode_hex_to_writer

arrow-json/src/reader/binary_array.rs:45–83

(hex_string: &str, writer: &mut W)

}

fn decode_hex_to_writer<W: Write>(hex_string: &str, writer: &mut W) -> Result<(), ArrowError> {
    let bytes = hex_string.as_bytes();
    let mut iter = bytes.chunks_exact(2);
    let mut buffer = [0u8; 64];
    let mut buffered = 0;

    for (pair_index, pair) in (&mut iter).enumerate() {
        let base = pair_index * 2;
        let high = decode_hex_digit(pair[0]).ok_or_else(|| invalid_hex_error_at(base, pair[0]))?;
        let low =
            decode_hex_digit(pair[1]).ok_or_else(|| invalid_hex_error_at(base + 1, pair[1]))?;
        buffer[buffered] = (high << 4) | low;
        buffered += 1;

        if buffered == buffer.len() {
            writer
                .write_all(&buffer)
                .map_err(|e| ArrowError::JsonError(format!("failed to write binary data: {e}")))?;
            buffered = 0;
        }
    }

    let remainder = iter.remainder();
    if !remainder.is_empty() {
        let index = (bytes.len() / 2) * 2;
        let low = decode_hex_digit(remainder[0])
            .ok_or_else(|| invalid_hex_error_at(index, remainder[0]))?;
        buffer[buffered] = low;
        buffered += 1;
    }

    if buffered > 0 {
        writer
            .write_all(&buffer[..buffered])
            .map_err(|e| ArrowError::JsonError(format!("failed to write binary data: {e}")))?;
    }

    Ok(())
}

#[derive(Default)]
pub struct BinaryArrayDecoder<O: OffsetSizeTrait> {