Function decode_block_range

nodedb-codec/src/fastlanes/mod.rs:130–158

Decode a range of blocks [start_block..end_block) from encoded data. More efficient than calling `decode_single_block` repeatedly — scans headers once to find start_block, then decodes contiguously.

(
    data: &[u8],
    start_block: usize,
    end_block: usize,
)

/// More efficient than calling `decode_single_block` repeatedly — scans
/// headers once to find start_block, then decodes contiguously.
pub fn decode_block_range(
    data: &[u8],
    start_block: usize,
    end_block: usize,
) -> Result<Vec<i64>, CodecError> {
    if data.len() < GLOBAL_HEADER_SIZE {
        return Err(CodecError::Truncated {
            expected: GLOBAL_HEADER_SIZE,
            actual: data.len(),
        });
    }
    let num_blocks = u16::from_le_bytes([data[4], data[5]]) as usize;
    if start_block >= num_blocks || end_block > num_blocks || start_block >= end_block {
        return Ok(Vec::new());
    }

    // Skip to start_block.
    let mut offset = GLOBAL_HEADER_SIZE;
    for i in 0..start_block {
        offset = skip_block(data, offset, i)?;
    }

    // Decode [start_block..end_block).
    let mut values = Vec::new();
    for i in start_block..end_block {
        offset = decode_block(data, offset, &mut values, i)?;
    }
    Ok(values)
}

/// Number of blocks in an encoded FastLanes stream.
pub fn block_count(data: &[u8]) -> Result<usize, CodecError> {