Method ReverseBlock

src/index/coinstatsindex.cpp:405–523

Reverse a single block as part of a reorg

// Reverse a single block as part of a reorg
bool CoinStatsIndex::ReverseBlock(const CBlock& block, const CBlockIndex* pindex)
{
    CBlockUndo block_undo;
    std::pair<uint256, DBVal> read_out;

    const CAmount block_subsidy{GetBlockSubsidy(pindex->nHeight, Params().GetConsensus())};
    m_total_subsidy -= block_subsidy;

    CAmount elements_block_fee{0};
    CAmount elements_coinbase_amount{0};

    // Ignore genesis block
    if (pindex->nHeight > 0) {
        if (!UndoReadFromDisk(block_undo, pindex)) {
            return false;
        }

        if (!m_db->Read(DBHeightKey(pindex->nHeight - 1), read_out)) {
            return false;
        }

        uint256 expected_block_hash{pindex->pprev->GetBlockHash()};
        if (read_out.first != expected_block_hash) {
            LogPrintf("WARNING: previous block header belongs to unexpected block %s; expected %s\n",
                      read_out.first.ToString(), expected_block_hash.ToString());

            if (!m_db->Read(DBHashKey(expected_block_hash), read_out)) {
                return error("%s: previous block header not found; expected %s",
                             __func__, expected_block_hash.ToString());
            }
        }
    }

    // Remove the new UTXOs that were created from the block
    for (size_t i = 0; i < block.vtx.size(); ++i) {
        const auto& tx{block.vtx.at(i)};

        for (uint32_t j = 0; j < tx->vout.size(); ++j) {
            const CTxOut& out{tx->vout[j]};
            COutPoint outpoint{tx->GetHash(), j};
            Coin coin{out, pindex->nHeight, tx->IsCoinBase()};

            // Skip unspendable coins
            if (coin.out.scriptPubKey.IsUnspendable()) {
                if (coin.out.nValue.IsExplicit()) {
                    if (coin.out.IsFee()) {
                        elements_block_fee += coin.out.nValue.GetAmount();
                    } else {
                        m_total_unspendable_amount -= coin.out.nValue.GetAmount();
                        m_total_unspendables_scripts -= coin.out.nValue.GetAmount();
                    }
                }
                continue;
            }

            m_muhash.Remove(MakeUCharSpan(TxOutSer(outpoint, coin)));

            if (coin.out.nValue.IsExplicit()) {