build.rs

pub use blake2b_rs::{Blake2b, Blake2bBuilder};
use includedir_codegen::Compression;

use std::{
    env,
    fs::File,
    io::{BufWriter, Read, Write},
    path::Path,
};

const PATH_PREFIX: &str = "specs/cells/";
const BUF_SIZE: usize = 8 * 1024;
const CKB_HASH_PERSONALIZATION: &[u8] = b"ckb-default-hash";

const BINARIES: &[(&str, &str)] = &[
    (
        "secp256k1_blake160_sighash_all",
        "709f3fda12f561cfacf92273c57a98fede188a3f1a59b1f888d113f9cce08649",
    ),
    (
        "secp256k1_data",
        "9799bee251b975b82c45a02154ce28cec89c5853ecc14d12b7b8cccfc19e0af4",
    ),
    (
        "dao",
        "2f7e76d1a866f7a064e251bf4f2b212a28b532dd6df19a87011784bdbe69726b",
    ),
    (
        "secp256k1_blake160_multisig_all",
        "50c8623ef5112510ccdf2d8e480d02d0de7288eb9968f8b019817340c3991145",
    ),
];

fn main() {
    let mut bundled = includedir_codegen::start("BUNDLED_CELL");

    let out_path = Path::new(&env::var("OUT_DIR").unwrap()).join("code_hashes.rs");
    let mut out_file = BufWriter::new(File::create(&out_path).expect("create code_hashes.rs"));

    let mut errors = Vec::new();

    for (name, expected_hash) in BINARIES {
        let path = format!("{}{}", PATH_PREFIX, name);

        let mut buf = [0u8; BUF_SIZE];
        bundled
            .add_file(&path, Compression::Gzip)
            .expect("add files to resource bundle");

        // build hash
        let mut blake2b = new_blake2b();
        let mut fd = File::open(&path).expect("open file");
        loop {
            let read_bytes = fd.read(&mut buf).expect("read file");
            if read_bytes > 0 {
                blake2b.update(&buf[..read_bytes]);
            } else {
                break;
            }
        }

        let mut hash = [0u8; 32];
        blake2b.finalize(&mut hash);

        let actual_hash = faster_hex::hex_string(&hash);
        if expected_hash != &actual_hash {
            errors.push((name, expected_hash, actual_hash));
            continue;
        }

        writeln!(
            &mut out_file,
            "pub const CODE_HASH_{}: [u8; 32] = {:?};",
            name.to_uppercase(),
            hash
        )
        .expect("write to code_hashes.rs");
    }

    if !errors.is_empty() {
        for (name, expected, actual) in errors.into_iter() {
            eprintln!("{}: expect {}, actual {}", name, expected, actual);
        }
        panic!("not all hashes are right");
    }

    bundled.build("bundled.rs").expect("build resource bundle");
}

pub fn new_blake2b() -> Blake2b {
    Blake2bBuilder::new(32)
        .personal(CKB_HASH_PERSONALIZATION)
        .build()
}