Make ATMP optionally return the CTransactionRefs it replaced

src/rpc/rawtransaction.cpp

@@ -899,7 +899,7 @@ UniValue sendrawtransaction(const JSONRPCRequest& request)
         // push to local node and sync with wallets
         CValidationState state;
         bool fMissingInputs;
-        if (!AcceptToMemoryPool(mempool, state, std::move(tx), fLimitFree, &fMissingInputs, false, nMaxRawTxFee)) {
+        if (!AcceptToMemoryPool(mempool, state, std::move(tx), fLimitFree, &fMissingInputs, NULL, false, nMaxRawTxFee)) {
             if (state.IsInvalid()) {
                 throw JSONRPCError(RPC_TRANSACTION_REJECTED, strprintf("%i: %s", state.GetRejectCode(), state.GetRejectReason()));
             } else {

src/test/txvalidationcache_tests.cpp

@@ -23,7 +23,7 @@ ToMemPool(CMutableTransaction& tx)
     LOCK(cs_main);
 
     CValidationState state;
-    return AcceptToMemoryPool(mempool, state, MakeTransactionRef(tx), false, NULL, true, 0);
+    return AcceptToMemoryPool(mempool, state, MakeTransactionRef(tx), false, NULL, NULL, true, 0);
 }
 
 BOOST_FIXTURE_TEST_CASE(tx_mempool_block_doublespend, TestChain100Setup)

src/validation.cpp

@@ -538,8 +538,8 @@ static bool IsCurrentForFeeEstimation()
 }
 
 bool AcceptToMemoryPoolWorker(CTxMemPool& pool, CValidationState& state, const CTransactionRef& ptx, bool fLimitFree,
-                              bool* pfMissingInputs, int64_t nAcceptTime, bool fOverrideMempoolLimit, const CAmount& nAbsurdFee,
+                              bool* pfMissingInputs, int64_t nAcceptTime, std::list<CTransactionRef>* plTxnReplaced,
-                              std::vector<uint256>& vHashTxnToUncache)
+                              bool fOverrideMempoolLimit, const CAmount& nAbsurdFee, std::vector<uint256>& vHashTxnToUncache)
 {
     const CTransaction& tx = *ptx;
     const uint256 hash = tx.GetHash();
@@ -950,6 +950,8 @@ bool AcceptToMemoryPoolWorker(CTxMemPool& pool, CValidationState& state, const C
                     hash.ToString(),
                     FormatMoney(nModifiedFees - nConflictingFees),
                     (int)nSize - (int)nConflictingSize);
+            if (plTxnReplaced)
+                plTxnReplaced->push_back(it->GetSharedTx());
         }
         pool.RemoveStaged(allConflicting, false);
 
@@ -975,10 +977,11 @@ bool AcceptToMemoryPoolWorker(CTxMemPool& pool, CValidationState& state, const C
 }
 
 bool AcceptToMemoryPoolWithTime(CTxMemPool& pool, CValidationState &state, const CTransactionRef &tx, bool fLimitFree,
-                        bool* pfMissingInputs, int64_t nAcceptTime, bool fOverrideMempoolLimit, const CAmount nAbsurdFee)
+                        bool* pfMissingInputs, int64_t nAcceptTime, std::list<CTransactionRef>* plTxnReplaced,
+                        bool fOverrideMempoolLimit, const CAmount nAbsurdFee)
 {
     std::vector<uint256> vHashTxToUncache;
-    bool res = AcceptToMemoryPoolWorker(pool, state, tx, fLimitFree, pfMissingInputs, nAcceptTime, fOverrideMempoolLimit, nAbsurdFee, vHashTxToUncache);
+    bool res = AcceptToMemoryPoolWorker(pool, state, tx, fLimitFree, pfMissingInputs, nAcceptTime, plTxnReplaced, fOverrideMempoolLimit, nAbsurdFee, vHashTxToUncache);
     if (!res) {
         BOOST_FOREACH(const uint256& hashTx, vHashTxToUncache)
             pcoinsTip->Uncache(hashTx);
@@ -990,9 +993,10 @@ bool AcceptToMemoryPoolWithTime(CTxMemPool& pool, CValidationState &state, const
 }
 
 bool AcceptToMemoryPool(CTxMemPool& pool, CValidationState &state, const CTransactionRef &tx, bool fLimitFree,
-                        bool* pfMissingInputs, bool fOverrideMempoolLimit, const CAmount nAbsurdFee)
+                        bool* pfMissingInputs, std::list<CTransactionRef>* plTxnReplaced,
+                        bool fOverrideMempoolLimit, const CAmount nAbsurdFee)
 {
-    return AcceptToMemoryPoolWithTime(pool, state, tx, fLimitFree, pfMissingInputs, GetTime(), fOverrideMempoolLimit, nAbsurdFee);
+    return AcceptToMemoryPoolWithTime(pool, state, tx, fLimitFree, pfMissingInputs, GetTime(), plTxnReplaced, fOverrideMempoolLimit, nAbsurdFee);
 }
 
 /** Return transaction in txOut, and if it was found inside a block, its hash is placed in hashBlock */
@@ -2138,7 +2142,7 @@ bool static DisconnectTip(CValidationState& state, const CChainParams& chainpara
             const CTransaction& tx = *it;
             // ignore validation errors in resurrected transactions
             CValidationState stateDummy;
-            if (tx.IsCoinBase() || !AcceptToMemoryPool(mempool, stateDummy, it, false, NULL, true)) {
+            if (tx.IsCoinBase() || !AcceptToMemoryPool(mempool, stateDummy, it, false, NULL, NULL, true)) {
                 mempool.removeRecursive(tx);
             } else if (mempool.exists(tx.GetHash())) {
                 vHashUpdate.push_back(tx.GetHash());

src/validation.h

@@ -304,13 +304,16 @@ void FlushStateToDisk();
 /** Prune block files and flush state to disk. */
 void PruneAndFlush();
 
-/** (try to) add transaction to memory pool **/
+/** (try to) add transaction to memory pool
+ * plTxnReplaced will be appended to with all transactions replaced from mempool **/
 bool AcceptToMemoryPool(CTxMemPool& pool, CValidationState &state, const CTransactionRef &tx, bool fLimitFree,
-                        bool* pfMissingInputs, bool fOverrideMempoolLimit=false, const CAmount nAbsurdFee=0);
+                        bool* pfMissingInputs, std::list<CTransactionRef>* plTxnReplaced = NULL,
+                        bool fOverrideMempoolLimit=false, const CAmount nAbsurdFee=0);
 
 /** (try to) add transaction to memory pool with a specified acceptance time **/
 bool AcceptToMemoryPoolWithTime(CTxMemPool& pool, CValidationState &state, const CTransactionRef &tx, bool fLimitFree,
-                        bool* pfMissingInputs, int64_t nAcceptTime, bool fOverrideMempoolLimit=false, const CAmount nAbsurdFee=0);
+                        bool* pfMissingInputs, int64_t nAcceptTime, std::list<CTransactionRef>* plTxnReplaced = NULL,
+                        bool fOverrideMempoolLimit=false, const CAmount nAbsurdFee=0);
 
 /** Convert CValidationState to a human-readable message for logging */
 std::string FormatStateMessage(const CValidationState &state);

src/wallet/wallet.cpp

@@ -3847,5 +3847,5 @@ int CMerkleTx::GetBlocksToMaturity() const
 
 bool CMerkleTx::AcceptToMemoryPool(const CAmount& nAbsurdFee, CValidationState& state)
 {
-    return ::AcceptToMemoryPool(mempool, state, tx, true, NULL, false, nAbsurdFee);
+    return ::AcceptToMemoryPool(mempool, state, tx, true, NULL, NULL, false, nAbsurdFee);
 }