Skip to content

More accurate fee/amount calculations in MakeCollateralAmounts #3640

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Closed
UdjinM6 wants to merge 1 commit into from
Closed

More accurate fee/amount calculations in MakeCollateralAmounts #3640

Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
21 changes: 16 additions & 5 deletions src/privatesend/privatesend-client.cpp
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -1424,8 +1424,17 @@ bool CPrivateSendClientSession::MakeCollateralAmounts(const CompactTallyItem& ta

if (!CPrivateSendClientOptions::IsEnabled() || !mixingWallet) return false;

CCoinControl coinControl;
// Every input will require at least this much fees in duffs
const CAmount nInputFee = GetMinimumFee(148, coinControl, ::mempool, ::feeEstimator, nullptr /* feeCalc */);
// Every output will require at least this much fees in duffs
const CAmount nOutputFee = GetMinimumFee(34, coinControl, ::mempool, ::feeEstimator, nullptr /* feeCalc */);

// We know we are going to spend all the outpoints and there should be one collateral output and maybe a change output too
CAmount nFees = tallyItem.vecOutPoints.size() * nInputFee + nOutputFee * 2;

// Skip way too tiny amounts
if (tallyItem.nAmount < CPrivateSend::GetCollateralAmount()) {
if (tallyItem.nAmount < CPrivateSend::GetCollateralAmount() + nFees) {
return false;
}

Expand Down Expand Up @@ -1456,18 +1465,20 @@ bool CPrivateSendClientSession::MakeCollateralAmounts(const CompactTallyItem& ta
scriptCollateral = GetScriptForDestination(vchPubKey.GetID());

CAmount nCollateralAmount{0};
if (tallyItem.nAmount > CPrivateSend::GetMaxCollateralAmount() + CPrivateSend::GetCollateralAmount()*2) {
if (tallyItem.nAmount > CPrivateSend::GetMaxCollateralAmount() + CPrivateSend::GetCollateralAmount() + nFees) {
// Change output will be large enough to be valid as a collateral or a source input for another run
nCollateralAmount = CPrivateSend::GetMaxCollateralAmount();
} else {
} else if (tallyItem.nAmount > CPrivateSend::GetMaxCollateralAmount()) {
// Change output might be too small for another collateral if we try to create the largest collateral
// here, create a slightly smaller one instead
nCollateralAmount = CPrivateSend::GetMaxCollateralAmount() - CPrivateSend::GetCollateralAmount();
nCollateralAmount = CPrivateSend::GetMaxCollateralAmount() - CPrivateSend::GetCollateralAmount() - nFees;
} else {
// No change output, use the tally amount and reduce fees
nCollateralAmount = tallyItem.nAmount - (nFees - nOutputFee);
}
vecSend.push_back((CRecipient){scriptCollateral, nCollateralAmount, false});

// try to use non-denominated and not mn-like funds first, select them explicitly
CCoinControl coinControl;
coinControl.fAllowOtherInputs = false;
coinControl.fAllowWatchOnly = false;
coinControl.nCoinType = CoinType::ONLY_NONDENOMINATED;
Expand Down