예제 #1
0
hash_digest build_merkle_tree(hash_list& merkle)
{
    if (merkle.empty())
        return null_hash;
    else if (merkle.size() == 1)
        return merkle[0];

    while (merkle.size() > 1)
    {
        if (merkle.size() % 2 != 0)
            merkle.push_back(merkle.back());

        hash_list new_merkle;
        for (auto it = merkle.begin(); it != merkle.end(); it += 2)
        {
            serializer concat;
            concat.write_hash(*it);
            concat.write_hash(*(it + 1));
            hash_digest new_root = generate_sha256_hash(concat.data());
            new_merkle.push_back(new_root);
        }
        merkle = new_merkle;
    }
    return merkle[0];
}
예제 #2
0
hash_digest build_merkle_tree(hash_list& merkle)
{
    // Stop if hash list is empty.
    if (merkle.empty())
        return null_hash;

    // While there is more than 1 hash in the list, keep looping...
    while (merkle.size() > 1)
    {
        // If number of hashes is odd, duplicate last hash in the list.
        if (merkle.size() % 2 != 0)
            merkle.push_back(merkle.back());

        // List size is now even.
        BITCOIN_ASSERT(merkle.size() % 2 == 0);

        // New hash list.
        hash_list new_merkle;

        // Loop through hashes 2 at a time.
        for (auto it = merkle.begin(); it != merkle.end(); it += 2)
        {
            // Join both current hashes together (concatenate).
            data_chunk concat_data;
            data_sink concat_stream(concat_data);
            ostream_writer concat_sink(concat_stream);
            concat_sink.write_hash(*it);
            concat_sink.write_hash(*(it + 1));
            concat_stream.flush();

            BITCOIN_ASSERT(concat_data.size() == (2 * hash_size));

            // Hash both of the hashes.
            const auto new_root = bitcoin_hash(concat_data);

            // Add this to the new list.
            new_merkle.push_back(new_root);
        }

        // This is the new list.
        merkle = new_merkle;
    }

    // Finally we end up with a single item.
    return merkle[0];
}