Method FillBlock

src/blockencodings.cpp:189–235

}

ReadStatus PartiallyDownloadedBlock::FillBlock(CBlock& block, const std::vector<CTransactionRef>& vtx_missing, bool segwit_active)
{
    if (header.IsNull()) return READ_STATUS_INVALID;

    block = header;
    block.vtx.resize(txn_available.size());

    size_t tx_missing_offset = 0;
    for (size_t i = 0; i < txn_available.size(); i++) {
        if (!txn_available[i]) {
            if (tx_missing_offset >= vtx_missing.size()) {
                return READ_STATUS_INVALID;
            }
            block.vtx[i] = vtx_missing[tx_missing_offset++];
        } else {
            block.vtx[i] = std::move(txn_available[i]);
        }
    }

    // Make sure we can't call FillBlock again.
    header.SetNull();
    txn_available.clear();

    if (vtx_missing.size() != tx_missing_offset) {
        return READ_STATUS_INVALID;
    }

    // Check for possible mutations early now that we have a seemingly good block
    IsBlockMutatedFn check_mutated{m_check_block_mutated_mock ? m_check_block_mutated_mock : IsBlockMutated};
    if (check_mutated(/*block=*/block, /*check_witness_root=*/segwit_active)) {
        return READ_STATUS_FAILED; // Possible Short ID collision
    }

    if (util::log::ShouldDebugLog(BCLog::CMPCTBLOCK)) {
        const uint256 hash{block.GetHash()};
        uint32_t tx_missing_size{0};
        for (const auto& tx : vtx_missing) tx_missing_size += tx->ComputeTotalSize();
        LogDebug(BCLog::CMPCTBLOCK, "Successfully reconstructed block %s with %u txn prefilled, %u txn from mempool (incl at least %u from extra pool) and %u txn (%u bytes) requested\n", hash.ToString(), prefilled_count, mempool_count, extra_count, vtx_missing.size(), tx_missing_size);
        if (vtx_missing.size() < 5) {
            for (const auto& tx : vtx_missing) {
                LogDebug(BCLog::CMPCTBLOCK, "Reconstructed block %s required tx %s\n", hash.ToString(), tx->GetHash().ToString());
            }
        }
    }

    return READ_STATUS_OK;
}