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Diffstat (limited to 'src/wallet/fees.cpp')
-rw-r--r-- | src/wallet/fees.cpp | 89 |
1 files changed, 89 insertions, 0 deletions
diff --git a/src/wallet/fees.cpp b/src/wallet/fees.cpp new file mode 100644 index 0000000000..73985dcf25 --- /dev/null +++ b/src/wallet/fees.cpp @@ -0,0 +1,89 @@ +// Copyright (c) 2009-2010 Satoshi Nakamoto +// Copyright (c) 2009-2017 The Bitcoin Core developers +// Distributed under the MIT software license, see the accompanying +// file COPYING or http://www.opensource.org/licenses/mit-license.php. + +#include <wallet/fees.h> + +#include <policy/policy.h> +#include <txmempool.h> +#include <util.h> +#include <validation.h> +#include <wallet/coincontrol.h> +#include <wallet/wallet.h> + + +CAmount GetRequiredFee(unsigned int nTxBytes) +{ + return std::max(CWallet::minTxFee.GetFee(nTxBytes), ::minRelayTxFee.GetFee(nTxBytes)); +} + + +CAmount GetMinimumFee(unsigned int nTxBytes, const CCoinControl& coin_control, const CTxMemPool& pool, const CBlockPolicyEstimator& estimator, FeeCalculation *feeCalc) +{ + /* User control of how to calculate fee uses the following parameter precedence: + 1. coin_control.m_feerate + 2. coin_control.m_confirm_target + 3. payTxFee (user-set global variable) + 4. nTxConfirmTarget (user-set global variable) + The first parameter that is set is used. + */ + CAmount fee_needed; + if (coin_control.m_feerate) { // 1. + fee_needed = coin_control.m_feerate->GetFee(nTxBytes); + if (feeCalc) feeCalc->reason = FeeReason::PAYTXFEE; + // Allow to override automatic min/max check over coin control instance + if (coin_control.fOverrideFeeRate) return fee_needed; + } + else if (!coin_control.m_confirm_target && ::payTxFee != CFeeRate(0)) { // 3. TODO: remove magic value of 0 for global payTxFee + fee_needed = ::payTxFee.GetFee(nTxBytes); + if (feeCalc) feeCalc->reason = FeeReason::PAYTXFEE; + } + else { // 2. or 4. + // We will use smart fee estimation + unsigned int target = coin_control.m_confirm_target ? *coin_control.m_confirm_target : ::nTxConfirmTarget; + // By default estimates are economical iff we are signaling opt-in-RBF + bool conservative_estimate = !coin_control.signalRbf; + // Allow to override the default fee estimate mode over the CoinControl instance + if (coin_control.m_fee_mode == FeeEstimateMode::CONSERVATIVE) conservative_estimate = true; + else if (coin_control.m_fee_mode == FeeEstimateMode::ECONOMICAL) conservative_estimate = false; + + fee_needed = estimator.estimateSmartFee(target, feeCalc, conservative_estimate).GetFee(nTxBytes); + if (fee_needed == 0) { + // if we don't have enough data for estimateSmartFee, then use fallbackFee + fee_needed = CWallet::fallbackFee.GetFee(nTxBytes); + if (feeCalc) feeCalc->reason = FeeReason::FALLBACK; + } + // Obey mempool min fee when using smart fee estimation + CAmount min_mempool_fee = pool.GetMinFee(gArgs.GetArg("-maxmempool", DEFAULT_MAX_MEMPOOL_SIZE) * 1000000).GetFee(nTxBytes); + if (fee_needed < min_mempool_fee) { + fee_needed = min_mempool_fee; + if (feeCalc) feeCalc->reason = FeeReason::MEMPOOL_MIN; + } + } + + // prevent user from paying a fee below minRelayTxFee or minTxFee + CAmount required_fee = GetRequiredFee(nTxBytes); + if (required_fee > fee_needed) { + fee_needed = required_fee; + if (feeCalc) feeCalc->reason = FeeReason::REQUIRED; + } + // But always obey the maximum + if (fee_needed > maxTxFee) { + fee_needed = maxTxFee; + if (feeCalc) feeCalc->reason = FeeReason::MAXTXFEE; + } + return fee_needed; +} + + +CFeeRate GetDiscardRate(const CBlockPolicyEstimator& estimator) +{ + unsigned int highest_target = estimator.HighestTargetTracked(FeeEstimateHorizon::LONG_HALFLIFE); + CFeeRate discard_rate = estimator.estimateSmartFee(highest_target, nullptr /* FeeCalculation */, false /* conservative */); + // Don't let discard_rate be greater than longest possible fee estimate if we get a valid fee estimate + discard_rate = (discard_rate == CFeeRate(0)) ? CWallet::m_discard_rate : std::min(discard_rate, CWallet::m_discard_rate); + // Discard rate must be at least dustRelayFee + discard_rate = std::max(discard_rate, ::dustRelayFee); + return discard_rate; +} |