diff options
Diffstat (limited to 'src/wallet/wallet.cpp')
-rw-r--r-- | src/wallet/wallet.cpp | 347 |
1 files changed, 174 insertions, 173 deletions
diff --git a/src/wallet/wallet.cpp b/src/wallet/wallet.cpp index f54405534a..bd5094085e 100644 --- a/src/wallet/wallet.cpp +++ b/src/wallet/wallet.cpp @@ -8,6 +8,7 @@ #include <checkpoints.h> #include <chain.h> #include <wallet/coincontrol.h> +#include <wallet/coinselection.h> #include <consensus/consensus.h> #include <consensus/validation.h> #include <fs.h> @@ -68,15 +69,6 @@ const uint256 CMerkleTx::ABANDON_HASH(uint256S("00000000000000000000000000000000 * @{ */ -struct CompareValueOnly -{ - bool operator()(const CInputCoin& t1, - const CInputCoin& t2) const - { - return t1.txout.nValue < t2.txout.nValue; - } -}; - std::string COutput::ToString() const { return strprintf("COutput(%s, %d, %d) [%s]", tx->GetHash().ToString(), i, nDepth, FormatMoney(tx->tx->vout[i].nValue)); @@ -1541,6 +1533,79 @@ int CWalletTx::GetRequestCount() const return nRequests; } +// Helper for producing a max-sized low-S signature (eg 72 bytes) +bool CWallet::DummySignInput(CTxIn &tx_in, const CTxOut &txout) const +{ + // Fill in dummy signatures for fee calculation. + const CScript& scriptPubKey = txout.scriptPubKey; + SignatureData sigdata; + + if (!ProduceSignature(DummySignatureCreator(this), scriptPubKey, sigdata)) + { + return false; + } else { + UpdateInput(tx_in, sigdata); + } + return true; +} + +// Helper for producing a bunch of max-sized low-S signatures (eg 72 bytes) +bool CWallet::DummySignTx(CMutableTransaction &txNew, const std::vector<CTxOut> &txouts) const +{ + // Fill in dummy signatures for fee calculation. + int nIn = 0; + for (const auto& txout : txouts) + { + if (!DummySignInput(txNew.vin[nIn], txout)) { + return false; + } + + nIn++; + } + return true; +} + +int64_t CalculateMaximumSignedTxSize(const CTransaction &tx, const CWallet *wallet) +{ + std::vector<CTxOut> txouts; + // Look up the inputs. We should have already checked that this transaction + // IsAllFromMe(ISMINE_SPENDABLE), so every input should already be in our + // wallet, with a valid index into the vout array, and the ability to sign. + for (auto& input : tx.vin) { + const auto mi = wallet->mapWallet.find(input.prevout.hash); + if (mi == wallet->mapWallet.end()) { + return -1; + } + assert(input.prevout.n < mi->second.tx->vout.size()); + txouts.emplace_back(mi->second.tx->vout[input.prevout.n]); + } + return CalculateMaximumSignedTxSize(tx, wallet, txouts); +} + +// txouts needs to be in the order of tx.vin +int64_t CalculateMaximumSignedTxSize(const CTransaction &tx, const CWallet *wallet, const std::vector<CTxOut>& txouts) +{ + CMutableTransaction txNew(tx); + if (!wallet->DummySignTx(txNew, txouts)) { + // This should never happen, because IsAllFromMe(ISMINE_SPENDABLE) + // implies that we can sign for every input. + return -1; + } + return GetVirtualTransactionSize(txNew); +} + +int CalculateMaximumSignedInputSize(const CTxOut& txout, const CWallet* wallet) +{ + CMutableTransaction txn; + txn.vin.push_back(CTxIn(COutPoint())); + if (!wallet->DummySignInput(txn.vin[0], txout)) { + // This should never happen, because IsAllFromMe(ISMINE_SPENDABLE) + // implies that we can sign for every input. + return -1; + } + return GetVirtualTransactionInputSize(txn.vin[0]); +} + void CWalletTx::GetAmounts(std::list<COutputEntry>& listReceived, std::list<COutputEntry>& listSent, CAmount& nFee, std::string& strSentAccount, const isminefilter& filter) const { @@ -2362,171 +2427,88 @@ const CTxOut& CWallet::FindNonChangeParentOutput(const CTransaction& tx, int out return ptx->vout[n]; } -static void ApproximateBestSubset(const std::vector<CInputCoin>& vValue, const CAmount& nTotalLower, const CAmount& nTargetValue, - std::vector<char>& vfBest, CAmount& nBest, int iterations = 1000) +bool CWallet::OutputEligibleForSpending(const COutput& output, const CoinEligibilityFilter& eligibilty_filter) const { - std::vector<char> vfIncluded; + if (!output.fSpendable) + return false; - vfBest.assign(vValue.size(), true); - nBest = nTotalLower; + if (output.nDepth < (output.tx->IsFromMe(ISMINE_ALL) ? eligibilty_filter.conf_mine : eligibilty_filter.conf_theirs)) + return false; - FastRandomContext insecure_rand; + if (!mempool.TransactionWithinChainLimit(output.tx->GetHash(), eligibilty_filter.max_ancestors)) + return false; - for (int nRep = 0; nRep < iterations && nBest != nTargetValue; nRep++) - { - vfIncluded.assign(vValue.size(), false); - CAmount nTotal = 0; - bool fReachedTarget = false; - for (int nPass = 0; nPass < 2 && !fReachedTarget; nPass++) - { - for (unsigned int i = 0; i < vValue.size(); i++) - { - //The solver here uses a randomized algorithm, - //the randomness serves no real security purpose but is just - //needed to prevent degenerate behavior and it is important - //that the rng is fast. We do not use a constant random sequence, - //because there may be some privacy improvement by making - //the selection random. - if (nPass == 0 ? insecure_rand.randbool() : !vfIncluded[i]) - { - nTotal += vValue[i].txout.nValue; - vfIncluded[i] = true; - if (nTotal >= nTargetValue) - { - fReachedTarget = true; - if (nTotal < nBest) - { - nBest = nTotal; - vfBest = vfIncluded; - } - nTotal -= vValue[i].txout.nValue; - vfIncluded[i] = false; - } - } - } - } - } + return true; } -bool CWallet::SelectCoinsMinConf(const CAmount& nTargetValue, const int nConfMine, const int nConfTheirs, const uint64_t nMaxAncestors, std::vector<COutput> vCoins, - std::set<CInputCoin>& setCoinsRet, CAmount& nValueRet) const +bool CWallet::SelectCoinsMinConf(const CAmount& nTargetValue, const CoinEligibilityFilter& eligibilty_filter, std::vector<COutput> vCoins, + std::set<CInputCoin>& setCoinsRet, CAmount& nValueRet, const CoinSelectionParams& coin_selection_params, bool& bnb_used) const { setCoinsRet.clear(); nValueRet = 0; - // List of values less than target - boost::optional<CInputCoin> coinLowestLarger; - std::vector<CInputCoin> vValue; - CAmount nTotalLower = 0; - - random_shuffle(vCoins.begin(), vCoins.end(), GetRandInt); + std::vector<CInputCoin> utxo_pool; + if (coin_selection_params.use_bnb) { - for (const COutput &output : vCoins) - { - if (!output.fSpendable) - continue; - - const CWalletTx *pcoin = output.tx; - - if (output.nDepth < (pcoin->IsFromMe(ISMINE_ALL) ? nConfMine : nConfTheirs)) - continue; - - if (!mempool.TransactionWithinChainLimit(pcoin->GetHash(), nMaxAncestors)) - continue; + // Get long term estimate + FeeCalculation feeCalc; + CCoinControl temp; + temp.m_confirm_target = 1008; + CFeeRate long_term_feerate = GetMinimumFeeRate(temp, ::mempool, ::feeEstimator, &feeCalc); - int i = output.i; - - CInputCoin coin = CInputCoin(pcoin, i); - - if (coin.txout.nValue == nTargetValue) - { - setCoinsRet.insert(coin); - nValueRet += coin.txout.nValue; - return true; - } - else if (coin.txout.nValue < nTargetValue + MIN_CHANGE) - { - vValue.push_back(coin); - nTotalLower += coin.txout.nValue; - } - else if (!coinLowestLarger || coin.txout.nValue < coinLowestLarger->txout.nValue) - { - coinLowestLarger = coin; - } - } + // Calculate cost of change + CAmount cost_of_change = GetDiscardRate(::feeEstimator).GetFee(coin_selection_params.change_spend_size) + coin_selection_params.effective_fee.GetFee(coin_selection_params.change_output_size); - if (nTotalLower == nTargetValue) - { - for (const auto& input : vValue) + // Filter by the min conf specs and add to utxo_pool and calculate effective value + for (const COutput &output : vCoins) { - setCoinsRet.insert(input); - nValueRet += input.txout.nValue; - } - return true; - } - - if (nTotalLower < nTargetValue) - { - if (!coinLowestLarger) - return false; - setCoinsRet.insert(coinLowestLarger.get()); - nValueRet += coinLowestLarger->txout.nValue; - return true; - } - - // Solve subset sum by stochastic approximation - std::sort(vValue.begin(), vValue.end(), CompareValueOnly()); - std::reverse(vValue.begin(), vValue.end()); - std::vector<char> vfBest; - CAmount nBest; - - ApproximateBestSubset(vValue, nTotalLower, nTargetValue, vfBest, nBest); - if (nBest != nTargetValue && nTotalLower >= nTargetValue + MIN_CHANGE) - ApproximateBestSubset(vValue, nTotalLower, nTargetValue + MIN_CHANGE, vfBest, nBest); + if (!OutputEligibleForSpending(output, eligibilty_filter)) + continue; - // If we have a bigger coin and (either the stochastic approximation didn't find a good solution, - // or the next bigger coin is closer), return the bigger coin - if (coinLowestLarger && - ((nBest != nTargetValue && nBest < nTargetValue + MIN_CHANGE) || coinLowestLarger->txout.nValue <= nBest)) - { - setCoinsRet.insert(coinLowestLarger.get()); - nValueRet += coinLowestLarger->txout.nValue; - } - else { - for (unsigned int i = 0; i < vValue.size(); i++) - if (vfBest[i]) - { - setCoinsRet.insert(vValue[i]); - nValueRet += vValue[i].txout.nValue; + CInputCoin coin(output.tx->tx, output.i); + coin.effective_value = coin.txout.nValue - (output.nInputBytes < 0 ? 0 : coin_selection_params.effective_fee.GetFee(output.nInputBytes)); + // Only include outputs that are positive effective value (i.e. not dust) + if (coin.effective_value > 0) { + coin.fee = output.nInputBytes < 0 ? 0 : coin_selection_params.effective_fee.GetFee(output.nInputBytes); + coin.long_term_fee = output.nInputBytes < 0 ? 0 : long_term_feerate.GetFee(output.nInputBytes); + utxo_pool.push_back(coin); } + } + // Calculate the fees for things that aren't inputs + CAmount not_input_fees = coin_selection_params.effective_fee.GetFee(coin_selection_params.tx_noinputs_size); + bnb_used = true; + return SelectCoinsBnB(utxo_pool, nTargetValue, cost_of_change, setCoinsRet, nValueRet, not_input_fees); + } else { + // Filter by the min conf specs and add to utxo_pool + for (const COutput &output : vCoins) + { + if (!OutputEligibleForSpending(output, eligibilty_filter)) + continue; - if (LogAcceptCategory(BCLog::SELECTCOINS)) { - LogPrint(BCLog::SELECTCOINS, "SelectCoins() best subset: "); - for (unsigned int i = 0; i < vValue.size(); i++) { - if (vfBest[i]) { - LogPrint(BCLog::SELECTCOINS, "%s ", FormatMoney(vValue[i].txout.nValue)); - } - } - LogPrint(BCLog::SELECTCOINS, "total %s\n", FormatMoney(nBest)); + CInputCoin coin = CInputCoin(output.tx->tx, output.i); + utxo_pool.push_back(coin); } + bnb_used = false; + return KnapsackSolver(nTargetValue, utxo_pool, setCoinsRet, nValueRet); } - - return true; } -bool CWallet::SelectCoins(const std::vector<COutput>& vAvailableCoins, const CAmount& nTargetValue, std::set<CInputCoin>& setCoinsRet, CAmount& nValueRet, const CCoinControl* coinControl) const +bool CWallet::SelectCoins(const std::vector<COutput>& vAvailableCoins, const CAmount& nTargetValue, std::set<CInputCoin>& setCoinsRet, CAmount& nValueRet, const CCoinControl& coin_control, const CoinSelectionParams& coin_selection_params, bool& bnb_used) const { std::vector<COutput> vCoins(vAvailableCoins); // coin control -> return all selected outputs (we want all selected to go into the transaction for sure) - if (coinControl && coinControl->HasSelected() && !coinControl->fAllowOtherInputs) + if (coin_control.HasSelected() && !coin_control.fAllowOtherInputs) { + // We didn't use BnB here, so set it to false. + bnb_used = false; + for (const COutput& out : vCoins) { if (!out.fSpendable) continue; nValueRet += out.tx->tx->vout[out.i].nValue; - setCoinsRet.insert(CInputCoin(out.tx, out.i)); + setCoinsRet.insert(CInputCoin(out.tx->tx, out.i)); } return (nValueRet >= nTargetValue); } @@ -2536,10 +2518,12 @@ bool CWallet::SelectCoins(const std::vector<COutput>& vAvailableCoins, const CAm CAmount nValueFromPresetInputs = 0; std::vector<COutPoint> vPresetInputs; - if (coinControl) - coinControl->ListSelected(vPresetInputs); + coin_control.ListSelected(vPresetInputs); for (const COutPoint& outpoint : vPresetInputs) { + // For now, don't use BnB if preset inputs are selected. TODO: Enable this later + bnb_used = false; + std::map<uint256, CWalletTx>::const_iterator it = mapWallet.find(outpoint.hash); if (it != mapWallet.end()) { @@ -2547,16 +2531,17 @@ bool CWallet::SelectCoins(const std::vector<COutput>& vAvailableCoins, const CAm // Clearly invalid input, fail if (pcoin->tx->vout.size() <= outpoint.n) return false; + // Just to calculate the marginal byte size nValueFromPresetInputs += pcoin->tx->vout[outpoint.n].nValue; - setPresetCoins.insert(CInputCoin(pcoin, outpoint.n)); + setPresetCoins.insert(CInputCoin(pcoin->tx, outpoint.n)); } else return false; // TODO: Allow non-wallet inputs } // remove preset inputs from vCoins - for (std::vector<COutput>::iterator it = vCoins.begin(); it != vCoins.end() && coinControl && coinControl->HasSelected();) + for (std::vector<COutput>::iterator it = vCoins.begin(); it != vCoins.end() && coin_control.HasSelected();) { - if (setPresetCoins.count(CInputCoin(it->tx, it->i))) + if (setPresetCoins.count(CInputCoin(it->tx->tx, it->i))) it = vCoins.erase(it); else ++it; @@ -2566,13 +2551,13 @@ bool CWallet::SelectCoins(const std::vector<COutput>& vAvailableCoins, const CAm bool fRejectLongChains = gArgs.GetBoolArg("-walletrejectlongchains", DEFAULT_WALLET_REJECT_LONG_CHAINS); bool res = nTargetValue <= nValueFromPresetInputs || - SelectCoinsMinConf(nTargetValue - nValueFromPresetInputs, 1, 6, 0, vCoins, setCoinsRet, nValueRet) || - SelectCoinsMinConf(nTargetValue - nValueFromPresetInputs, 1, 1, 0, vCoins, setCoinsRet, nValueRet) || - (bSpendZeroConfChange && SelectCoinsMinConf(nTargetValue - nValueFromPresetInputs, 0, 1, 2, vCoins, setCoinsRet, nValueRet)) || - (bSpendZeroConfChange && SelectCoinsMinConf(nTargetValue - nValueFromPresetInputs, 0, 1, std::min((size_t)4, nMaxChainLength/3), vCoins, setCoinsRet, nValueRet)) || - (bSpendZeroConfChange && SelectCoinsMinConf(nTargetValue - nValueFromPresetInputs, 0, 1, nMaxChainLength/2, vCoins, setCoinsRet, nValueRet)) || - (bSpendZeroConfChange && SelectCoinsMinConf(nTargetValue - nValueFromPresetInputs, 0, 1, nMaxChainLength, vCoins, setCoinsRet, nValueRet)) || - (bSpendZeroConfChange && !fRejectLongChains && SelectCoinsMinConf(nTargetValue - nValueFromPresetInputs, 0, 1, std::numeric_limits<uint64_t>::max(), vCoins, setCoinsRet, nValueRet)); + SelectCoinsMinConf(nTargetValue - nValueFromPresetInputs, CoinEligibilityFilter(1, 6, 0), vCoins, setCoinsRet, nValueRet, coin_selection_params, bnb_used) || + SelectCoinsMinConf(nTargetValue - nValueFromPresetInputs, CoinEligibilityFilter(1, 1, 0), vCoins, setCoinsRet, nValueRet, coin_selection_params, bnb_used) || + (bSpendZeroConfChange && SelectCoinsMinConf(nTargetValue - nValueFromPresetInputs, CoinEligibilityFilter(0, 1, 2), vCoins, setCoinsRet, nValueRet, coin_selection_params, bnb_used)) || + (bSpendZeroConfChange && SelectCoinsMinConf(nTargetValue - nValueFromPresetInputs, CoinEligibilityFilter(0, 1, std::min((size_t)4, nMaxChainLength/3)), vCoins, setCoinsRet, nValueRet, coin_selection_params, bnb_used)) || + (bSpendZeroConfChange && SelectCoinsMinConf(nTargetValue - nValueFromPresetInputs, CoinEligibilityFilter(0, 1, nMaxChainLength/2), vCoins, setCoinsRet, nValueRet, coin_selection_params, bnb_used)) || + (bSpendZeroConfChange && SelectCoinsMinConf(nTargetValue - nValueFromPresetInputs, CoinEligibilityFilter(0, 1, nMaxChainLength), vCoins, setCoinsRet, nValueRet, coin_selection_params, bnb_used)) || + (bSpendZeroConfChange && !fRejectLongChains && SelectCoinsMinConf(nTargetValue - nValueFromPresetInputs, CoinEligibilityFilter(0, 1, std::numeric_limits<uint64_t>::max()), vCoins, setCoinsRet, nValueRet, coin_selection_params, bnb_used)); // because SelectCoinsMinConf clears the setCoinsRet, we now add the possible inputs to the coinset setCoinsRet.insert(setPresetCoins.begin(), setPresetCoins.end()); @@ -2748,13 +2733,14 @@ bool CWallet::CreateTransaction(const std::vector<CRecipient>& vecSend, CTransac assert(txNew.nLockTime < LOCKTIME_THRESHOLD); FeeCalculation feeCalc; CAmount nFeeNeeded; - unsigned int nBytes; + int nBytes; { std::set<CInputCoin> setCoins; LOCK2(cs_main, cs_wallet); { std::vector<COutput> vAvailableCoins; AvailableCoins(vAvailableCoins, true, &coin_control); + CoinSelectionParams coin_selection_params; // Parameters for coin selection, init with dummy // Create change script that will be used if we need change // TODO: pass in scriptChange instead of reservekey so @@ -2788,12 +2774,20 @@ bool CWallet::CreateTransaction(const std::vector<CRecipient>& vecSend, CTransac scriptChange = GetScriptForDestination(GetDestinationForKey(vchPubKey, change_type)); } CTxOut change_prototype_txout(0, scriptChange); - size_t change_prototype_size = GetSerializeSize(change_prototype_txout, SER_DISK, 0); + coin_selection_params.change_output_size = GetSerializeSize(change_prototype_txout, SER_DISK, 0); CFeeRate discard_rate = GetDiscardRate(::feeEstimator); + + // Get the fee rate to use effective values in coin selection + CFeeRate nFeeRateNeeded = GetMinimumFeeRate(coin_control, ::mempool, ::feeEstimator, &feeCalc); + nFeeRet = 0; bool pick_new_inputs = true; CAmount nValueIn = 0; + + // BnB selector is the only selector used when this is true. + // That should only happen on the first pass through the loop. + coin_selection_params.use_bnb = nSubtractFeeFromAmount == 0; // If we are doing subtract fee from recipient, then don't use BnB // Start with no fee and loop until there is enough fee while (true) { @@ -2805,7 +2799,9 @@ bool CWallet::CreateTransaction(const std::vector<CRecipient>& vecSend, CTransac CAmount nValueToSelect = nValue; if (nSubtractFeeFromAmount == 0) nValueToSelect += nFeeRet; + // vouts to the payees + coin_selection_params.tx_noinputs_size = 11; // Static vsize overhead + outputs vsize. 4 nVersion, 4 nLocktime, 1 input count, 1 output count, 1 witness overhead (dummy, flag, stack size) for (const auto& recipient : vecSend) { CTxOut txout(recipient.nAmount, recipient.scriptPubKey); @@ -2821,6 +2817,8 @@ bool CWallet::CreateTransaction(const std::vector<CRecipient>& vecSend, CTransac txout.nValue -= nFeeRet % nSubtractFeeFromAmount; } } + // Include the fee cost for outputs. Note this is only used for BnB right now + coin_selection_params.tx_noinputs_size += ::GetSerializeSize(txout, SER_NETWORK, PROTOCOL_VERSION); if (IsDust(txout, ::dustRelayFee)) { @@ -2839,18 +2837,27 @@ bool CWallet::CreateTransaction(const std::vector<CRecipient>& vecSend, CTransac } // Choose coins to use + bool bnb_used; if (pick_new_inputs) { nValueIn = 0; setCoins.clear(); - if (!SelectCoins(vAvailableCoins, nValueToSelect, setCoins, nValueIn, &coin_control)) + coin_selection_params.change_spend_size = CalculateMaximumSignedInputSize(change_prototype_txout, this); + coin_selection_params.effective_fee = nFeeRateNeeded; + if (!SelectCoins(vAvailableCoins, nValueToSelect, setCoins, nValueIn, coin_control, coin_selection_params, bnb_used)) { - strFailReason = _("Insufficient funds"); - return false; + // If BnB was used, it was the first pass. No longer the first pass and continue loop with knapsack. + if (bnb_used) { + coin_selection_params.use_bnb = false; + continue; + } + else { + strFailReason = _("Insufficient funds"); + return false; + } } } const CAmount nChange = nValueIn - nValueToSelect; - if (nChange > 0) { // Fill a vout to ourself @@ -2858,7 +2865,8 @@ bool CWallet::CreateTransaction(const std::vector<CRecipient>& vecSend, CTransac // Never create dust outputs; if we would, just // add the dust to the fee. - if (IsDust(newTxOut, discard_rate)) + // The nChange when BnB is used is always going to go to fees. + if (IsDust(newTxOut, discard_rate) || bnb_used) { nChangePosInOut = -1; nFeeRet += nChange; @@ -2898,20 +2906,12 @@ bool CWallet::CreateTransaction(const std::vector<CRecipient>& vecSend, CTransac txNew.vin.push_back(CTxIn(coin.outpoint,CScript(), nSequence)); - // Fill in dummy signatures for fee calculation. - if (!DummySignTx(txNew, setCoins)) { + nBytes = CalculateMaximumSignedTxSize(txNew, this); + if (nBytes < 0) { strFailReason = _("Signing transaction failed"); return false; } - nBytes = GetVirtualTransactionSize(txNew); - - // Remove scriptSigs to eliminate the fee calculation dummy signatures - for (auto& vin : txNew.vin) { - vin.scriptSig = CScript(); - vin.scriptWitness.SetNull(); - } - nFeeNeeded = GetMinimumFee(nBytes, coin_control, ::mempool, ::feeEstimator, &feeCalc); if (feeCalc.reason == FeeReason::FALLBACK && !g_wallet_allow_fallback_fee) { // eventually allow a fallback fee @@ -2939,7 +2939,7 @@ bool CWallet::CreateTransaction(const std::vector<CRecipient>& vecSend, CTransac // (because of reduced tx size) and so we should add a // change output. Only try this once. if (nChangePosInOut == -1 && nSubtractFeeFromAmount == 0 && pick_new_inputs) { - unsigned int tx_size_with_change = nBytes + change_prototype_size + 2; // Add 2 as a buffer in case increasing # of outputs changes compact size + unsigned int tx_size_with_change = nBytes + coin_selection_params.change_output_size + 2; // Add 2 as a buffer in case increasing # of outputs changes compact size CAmount fee_needed_with_change = GetMinimumFee(tx_size_with_change, coin_control, ::mempool, ::feeEstimator, nullptr); CAmount minimum_value_for_change = GetDustThreshold(change_prototype_txout, discard_rate); if (nFeeRet >= fee_needed_with_change + minimum_value_for_change) { @@ -2987,6 +2987,7 @@ bool CWallet::CreateTransaction(const std::vector<CRecipient>& vecSend, CTransac // Include more fee and try again. nFeeRet = nFeeNeeded; + coin_selection_params.use_bnb = false; continue; } } |