Function finish_layer

atomic-repository/src/oci.rs:267–285

Finalize an uncompressed tar buffer into an [`OciLayer`]: compute the uncompressed digest (`diff_id`), gzip the bytes, and compute the gzipped digest and size.

(tar_buf: Vec<u8>)

/// uncompressed digest (`diff_id`), gzip the bytes, and compute the gzipped
/// digest and size.
fn finish_layer(tar_buf: Vec<u8>) -> std::io::Result<OciLayer> {
    let diff_id = format!("sha256:{}", sha256_hex(&tar_buf));

    let mut tar_gz = Vec::new();
    {
        let mut encoder = GzEncoder::new(&mut tar_gz, Compression::default());
        encoder.write_all(&tar_buf)?;
        encoder.finish()?;
    }

    let digest = format!("sha256:{}", sha256_hex(&tar_gz));
    let size = tar_gz.len() as u64;
    Ok(OciLayer {
        tar_gz,
        diff_id,
        digest,
        size,
    })
}

/// Encode the OCI whiteout entry name for a deleted path.
fn whiteout_path(path: &str) -> String {