Merge #9262: Prefer coins that have fewer ancestors, sanity check txn before ATMP

cee1612 reduce number of lookups in TransactionWithinChainLimit (Gregory Sanders)
af9bedb Test for fix of txn chaining in wallet (Gregory Sanders)
5882c09 CreateTransaction: Don't return success with too-many-ancestor txn (Gregory Sanders)
0b2294a SelectCoinsMinConf: Prefer coins with fewer ancestors (Gregory Sanders)

1 files changed, 30 insertions, 4 deletions

diff --git a/src/wallet/wallet.cpp b/src/wallet/wallet.cpp
index aef3922b9..c4051d2ac 100644
--- a/src/wallet/wallet.cpp
+++ b/src/wallet/wallet.cpp
@@ -2018,7 +2018,7 @@ static void ApproximateBestSubset(vector<pair<CAmount, pair<const CWalletTx*,uns
     }
 }
 
-bool CWallet::SelectCoinsMinConf(const CAmount& nTargetValue, int nConfMine, int nConfTheirs, vector<COutput> vCoins,
+bool CWallet::SelectCoinsMinConf(const CAmount& nTargetValue, const int nConfMine, const int nConfTheirs, const uint64_t nMaxAncestors, vector<COutput> vCoins,
                                  set<pair<const CWalletTx*,unsigned int> >& setCoinsRet, CAmount& nValueRet) const
 {
     setCoinsRet.clear();
@@ -2043,6 +2043,9 @@ bool CWallet::SelectCoinsMinConf(const CAmount& nTargetValue, int nConfMine, int
         if (output.nDepth < (pcoin->IsFromMe(ISMINE_ALL) ? nConfMine : nConfTheirs))
             continue;
 
+        if (!mempool.TransactionWithinChainLimit(pcoin->GetHash(), nMaxAncestors))
+            continue;
+
         int i = output.i;
         CAmount n = pcoin->tx->vout[i].nValue;
 
@@ -2168,10 +2171,17 @@ bool CWallet::SelectCoins(const vector<COutput>& vAvailableCoins, const CAmount&
             ++it;
     }
 
+    size_t nMaxChainLength = std::min(GetArg("-limitancestorcount", DEFAULT_ANCESTOR_LIMIT), GetArg("-limitdescendantcount", DEFAULT_DESCENDANT_LIMIT));
+    bool fRejectLongChains = GetBoolArg("-walletrejectlongchains", DEFAULT_WALLET_REJECT_LONG_CHAINS);
+
     bool res = nTargetValue <= nValueFromPresetInputs ||
-        SelectCoinsMinConf(nTargetValue - nValueFromPresetInputs, 1, 6, vCoins, setCoinsRet, nValueRet) ||
-        SelectCoinsMinConf(nTargetValue - nValueFromPresetInputs, 1, 1, vCoins, setCoinsRet, nValueRet) ||
-        (bSpendZeroConfChange && SelectCoinsMinConf(nTargetValue - nValueFromPresetInputs, 0, 1, vCoins, setCoinsRet, nValueRet));
+        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));
 
     // because SelectCoinsMinConf clears the setCoinsRet, we now add the possible inputs to the coinset
     setCoinsRet.insert(setPresetCoins.begin(), setPresetCoins.end());
@@ -2550,6 +2560,21 @@ bool CWallet::CreateTransaction(const vector<CRecipient>& vecSend, CWalletTx& wt
         }
     }
 
+    if (GetBoolArg("-walletrejectlongchains", DEFAULT_WALLET_REJECT_LONG_CHAINS)) {
+        // Lastly, ensure this tx will pass the mempool's chain limits
+        LockPoints lp;
+        CTxMemPoolEntry entry(txNew, 0, 0, 0, 0, false, 0, false, 0, lp);
+        CTxMemPool::setEntries setAncestors;
+        size_t nLimitAncestors = GetArg("-limitancestorcount", DEFAULT_ANCESTOR_LIMIT);
+        size_t nLimitAncestorSize = GetArg("-limitancestorsize", DEFAULT_ANCESTOR_SIZE_LIMIT)*1000;
+        size_t nLimitDescendants = GetArg("-limitdescendantcount", DEFAULT_DESCENDANT_LIMIT);
+        size_t nLimitDescendantSize = GetArg("-limitdescendantsize", DEFAULT_DESCENDANT_SIZE_LIMIT)*1000;
+        std::string errString;
+        if (!mempool.CalculateMemPoolAncestors(entry, setAncestors, nLimitAncestors, nLimitAncestorSize, nLimitDescendants, nLimitDescendantSize, errString)) {
+            strFailReason = _("Transaction has too long of a mempool chain");
+            return false;
+        }
+    }
     return true;
 }
 
@@ -3374,6 +3399,7 @@ std::string CWallet::GetWalletHelpString(bool showDebug)
         strUsage += HelpMessageOpt("-dblogsize=<n>", strprintf("Flush wallet database activity from memory to disk log every <n> megabytes (default: %u)", DEFAULT_WALLET_DBLOGSIZE));
         strUsage += HelpMessageOpt("-flushwallet", strprintf("Run a thread to flush wallet periodically (default: %u)", DEFAULT_FLUSHWALLET));
         strUsage += HelpMessageOpt("-privdb", strprintf("Sets the DB_PRIVATE flag in the wallet db environment (default: %u)", DEFAULT_WALLET_PRIVDB));
+        strUsage += HelpMessageOpt("-walletrejectlongchains", strprintf(_("Wallet will not create transactions that violate mempool chain limits (default: %u"), DEFAULT_WALLET_REJECT_LONG_CHAINS));
     }
 
     return strUsage;