use undo data for prevouts

Completely untested.

Author: theuni

src/bitcoin-coinjoins.cpp

@@ -31,6 +31,7 @@
 #include <util/signalinterrupt.h>
 #include <util/task_runner.h>
 #include <util/translation.h>
+#include <undo.h>
 #include <validation.h>
 #include <validationinterface.h>
 
@@ -171,16 +172,19 @@ int main(int argc, char* argv[])
             LOCK(chainman.GetMutex());
             current_block = chainman.ActiveChain()[block_height];
         }
-	CCoinsViewCache &view = chainman.ActiveChainstate().CoinsTip();
 	std::cout << "AFTER VIEW" << std::endl;
 	std::cout << "BEFORE LOOP" << std::endl;
 
         while (current_block) {
 	  std::cout << "TEST" << std::endl;
 
             CBlock block;
-            chainman.m_blockman.ReadBlockFromDisk(block, *current_block);
-            CFeeRate fee_rate = GetMedianFeeRateFromBlock(block, view);
+            CBlockUndo undo;
+            bool read_success = false;
+            read_success = chainman.m_blockman.ReadBlockFromDisk(block, *current_block);
+            read_success &= chainman.m_blockman.UndoReadFromDisk(undo, *current_block);
+            assert(read_success);
+            CFeeRate fee_rate = GetMedianFeeRateFromBlock(block, undo);
             // the get feerate function
 
             for (const CTransactionRef& tx : block.vtx) {

src/util/coinjoins.cpp

@@ -6,6 +6,7 @@
 #include <coins.h>
 #include <consensus/validation.h>
 #include <util/coinjoins.h>
+#include <undo.h>
 
 bool WhirlpoolTransactions::isWhirlpool(const CTransactionRef& tx) {
     if (tx->vin.size() == 5 && tx->vout.size() == 5) {
@@ -29,15 +30,17 @@ bool WhirlpoolTransactions::isWhirlpool(const CTransactionRef& tx) {
     return false;
 }
 
-CFeeRate GetMedianFeeRateFromBlock(const CBlock& block, CCoinsViewCache &view) {
+CFeeRate GetMedianFeeRateFromBlock(const CBlock& block, const CBlockUndo &undo) {
     // calculate median fee rate
     std::vector<CFeeRate> feeRates;
-    for (const auto& tx : block.vtx) {
+    // Skip coinbase
+    for(size_t txindex = 1; txindex < block.vtx.size(); txindex++) {
+      const auto& tx = block.vtx[txindex];
+      // vtxundo is offset by 1 because the coinbase tx is not present.
+      const auto& undotx = undo.vtxundo[txindex - 1];
       CAmount value_in = 0;
-      for (auto &v : tx->vin) {
-        const COutPoint &prevout = v.prevout;
-        const Coin& coin = view.AccessCoin(prevout);
-        value_in += coin.out.nValue;
+      for (const auto& prevout : undotx.vprevout) {
+           value_in += prevout.out.nValue;
       }
       CAmount value_out = tx->GetValueOut();
       size_t txSize = GetTransactionWeight(*tx);

src/util/coinjoins.h

@@ -55,8 +55,8 @@ class Tx0s {
         return tx0_set.size();
     }
 };
-
-CFeeRate GetMedianFeeRateFromBlock(const CBlock& block, CCoinsViewCache &view);
+class CBlockUndo;
+CFeeRate GetMedianFeeRateFromBlock(const CBlock& block, const CBlockUndo& undo);
 
 class WhirlpoolTransactions {
     Tx0s tx0s;