wallet: Remove sendfree

This removes the option from the wallet to not pay a fee on "small"
transactions which spend "old" inputs.

This code is no longer worth keeping around, as almost all miners
prefer not to include transactions which pay no fee at all.

1 files changed, 2 insertions, 31 deletions

diff --git a/src/wallet/wallet.cpp b/src/wallet/wallet.cpp
index 63501b04be..cf3c6ee121 100644
--- a/src/wallet/wallet.cpp
+++ b/src/wallet/wallet.cpp
@@ -39,7 +39,6 @@ CWallet* pwalletMain = NULL;
 CFeeRate payTxFee(DEFAULT_TRANSACTION_FEE);
 unsigned int nTxConfirmTarget = DEFAULT_TX_CONFIRM_TARGET;
 bool bSpendZeroConfChange = DEFAULT_SPEND_ZEROCONF_CHANGE;
-bool fSendFreeTransactions = DEFAULT_SEND_FREE_TRANSACTIONS;
 bool fWalletRbf = DEFAULT_WALLET_RBF;
 
 const char * DEFAULT_WALLET_DAT = "wallet.dat";
@@ -2449,7 +2448,6 @@ bool CWallet::CreateTransaction(const vector<CRecipient>& vecSend, CWalletTx& wt
                 CAmount nValueToSelect = nValue;
                 if (nSubtractFeeFromAmount == 0)
                     nValueToSelect += nFeeRet;
-                double dPriority = 0;
                 // vouts to the payees
                 for (const auto& recipient : vecSend)
                 {
@@ -2490,19 +2488,6 @@ bool CWallet::CreateTransaction(const vector<CRecipient>& vecSend, CWalletTx& wt
                     strFailReason = _("Insufficient funds");
                     return false;
                 }
-                for (const auto& pcoin : setCoins)
-                {
-                    CAmount nCredit = pcoin.first->tx->vout[pcoin.second].nValue;
-                    //The coin age after the next block (depth+1) is used instead of the current,
-                    //reflecting an assumption the user would accept a bit more delay for
-                    //a chance at a free transaction.
-                    //But mempool inputs might still be in the mempool, so their age stays 0
-                    int age = pcoin.first->GetDepthInMainChain();
-                    assert(age >= 0);
-                    if (age != 0)
-                        age += 1;
-                    dPriority += (double)nCredit * age;
-                }
 
                 const CAmount nChange = nValueIn - nValueToSelect;
                 if (nChange > 0)
@@ -2614,7 +2599,6 @@ bool CWallet::CreateTransaction(const vector<CRecipient>& vecSend, CWalletTx& wt
                 unsigned int nBytes = GetVirtualTransactionSize(txNew);
 
                 CTransaction txNewConst(txNew);
-                dPriority = txNewConst.ComputePriority(dPriority, nBytes);
 
                 // Remove scriptSigs to eliminate the fee calculation dummy signatures
                 for (auto& vin : txNew.vin) {
@@ -2627,16 +2611,6 @@ bool CWallet::CreateTransaction(const vector<CRecipient>& vecSend, CWalletTx& wt
                 if (coinControl && coinControl->nConfirmTarget > 0)
                     currentConfirmationTarget = coinControl->nConfirmTarget;
 
-                // Can we complete this as a free transaction?
-                if (fSendFreeTransactions && nBytes <= MAX_FREE_TRANSACTION_CREATE_SIZE)
-                {
-                    // Not enough fee: enough priority?
-                    double dPriorityNeeded = mempool.estimateSmartPriority(currentConfirmationTarget);
-                    // Require at least hard-coded AllowFree.
-                    if (dPriority >= dPriorityNeeded && AllowFree(dPriority))
-                        break;
-                }
-
                 CAmount nFeeNeeded = GetMinimumFee(nBytes, currentConfirmationTarget, mempool);
                 if (coinControl && nFeeNeeded > 0 && coinControl->nMinimumTotalFee > nFeeNeeded) {
                     nFeeNeeded = coinControl->nMinimumTotalFee;
@@ -3548,8 +3522,6 @@ std::string CWallet::GetWalletHelpString(bool showDebug)
                                                             CURRENCY_UNIT, FormatMoney(payTxFee.GetFeePerK())));
     strUsage += HelpMessageOpt("-rescan", _("Rescan the block chain for missing wallet transactions on startup"));
     strUsage += HelpMessageOpt("-salvagewallet", _("Attempt to recover private keys from a corrupt wallet on startup"));
-    if (showDebug)
-        strUsage += HelpMessageOpt("-sendfreetransactions", strprintf(_("Send transactions as zero-fee transactions if possible (default: %u)"), DEFAULT_SEND_FREE_TRANSACTIONS));
     strUsage += HelpMessageOpt("-spendzeroconfchange", strprintf(_("Spend unconfirmed change when sending transactions (default: %u)"), DEFAULT_SPEND_ZEROCONF_CHANGE));
     strUsage += HelpMessageOpt("-txconfirmtarget=<n>", strprintf(_("If paytxfee is not set, include enough fee so transactions begin confirmation on average within n blocks (default: %u)"), DEFAULT_TX_CONFIRM_TARGET));
     strUsage += HelpMessageOpt("-usehd", _("Use hierarchical deterministic key generation (HD) after BIP32. Only has effect during wallet creation/first start") + " " + strprintf(_("(default: %u)"), DEFAULT_USE_HD_WALLET));
@@ -3868,11 +3840,10 @@ bool CWallet::ParameterInteraction()
     }
     nTxConfirmTarget = GetArg("-txconfirmtarget", DEFAULT_TX_CONFIRM_TARGET);
     bSpendZeroConfChange = GetBoolArg("-spendzeroconfchange", DEFAULT_SPEND_ZEROCONF_CHANGE);
-    fSendFreeTransactions = GetBoolArg("-sendfreetransactions", DEFAULT_SEND_FREE_TRANSACTIONS);
     fWalletRbf = GetBoolArg("-walletrbf", DEFAULT_WALLET_RBF);
 
-    if (fSendFreeTransactions && GetArg("-limitfreerelay", DEFAULT_LIMITFREERELAY) <= 0)
-        return InitError("Creation of free transactions with their relay disabled is not supported.");
+    if (GetBoolArg("-sendfreetransactions", false))
+        InitWarning("The argument -sendfreetransactions is no longer supported.");
 
     return true;
 }