diff options
| author | Alex Morcos <morcos@chaincode.com> | 2017-08-25 14:46:07 -0500 |
|---|---|---|
| committer | Wladimir J. van der Laan <laanwj@gmail.com> | 2017-08-28 10:14:55 +0200 |
| commit | e51bb71e4a5657f1ea7a046aefe1f24f6674f6ad (patch) | |
| tree | b0df2dde6a98cf57c7765abca61769831294b67d | |
| parent | 0a6af47ffabbeee29fec5b5d71eaff43a08969da (diff) | |
Fix rounding errors in calculation of minimum change size
Github-Pull: #11145
Rebased-From: a54c7b94f8825e9b52fec9066fe7c1d5b6f53482
Tree-SHA512: d9abb9794edbf7e52450c63d183a4f28e9a3621a670b7f21af92407be096363b44a356818f2abbea11c168d123c04852bd0b60f1cd9d423aefbf4ae831f8567d
| -rw-r--r-- | src/wallet/wallet.cpp | 16 |
1 files changed, 9 insertions, 7 deletions
diff --git a/src/wallet/wallet.cpp b/src/wallet/wallet.cpp index 680c5ed9b3..142e04c7c8 100644 --- a/src/wallet/wallet.cpp +++ b/src/wallet/wallet.cpp @@ -2852,13 +2852,15 @@ bool CWallet::CreateTransaction(const std::vector<CRecipient>& vecSend, CWalletT // new inputs. We now know we only need the smaller fee // (because of reduced tx size) and so we should add a // change output. Only try this once. - CAmount fee_needed_for_change = GetMinimumFee(change_prototype_size, coin_control, ::mempool, ::feeEstimator, nullptr); - CAmount minimum_value_for_change = GetDustThreshold(change_prototype_txout, discard_rate); - CAmount max_excess_fee = fee_needed_for_change + minimum_value_for_change; - if (nFeeRet > nFeeNeeded + max_excess_fee && nChangePosInOut == -1 && nSubtractFeeFromAmount == 0 && pick_new_inputs) { - pick_new_inputs = false; - nFeeRet = nFeeNeeded + fee_needed_for_change; - continue; + 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 + 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) { + pick_new_inputs = false; + nFeeRet = fee_needed_with_change; + continue; + } } // If we have change output already, just increase it |