Merge #9381: Remove CWalletTx merging logic from AddToWallet

28b112e9bd3fd1181c0720306051ba7efca8b436 Get rid of BindWallet (Russell Yanofsky)
d002f9d15d938e78360ad906f2d74a249c7e923e Disable CWalletTx copy constructor (Russell Yanofsky)
65b9d8f8ddb5a838454efc8bdd6576f0deb65f6d Avoid copying CWalletTx in LoadToWallet (Russell Yanofsky)
bd2fbc7cdbec46400341209f4cb7e69e5b2cee19 Get rid of unneeded CWalletTx::Init parameter (Russell Yanofsky)
2b9cba206594bfbcefcef0c88a0bf793819643bd Remove CWalletTx merging logic from AddToWallet (Russell Yanofsky)

Pull request description:

  This is a pure refactoring, no behavior is changing.

  Instead of AddToWallet taking a temporary CWalletTx object and then potentially merging it with a pre-existing CWalletTx, have it take a callback so callers can update the pre-existing CWalletTx directly.

  This makes AddToWallet simpler because now it is only has to be concerned with saving CWalletTx objects and not merging them.

  This makes AddToWallet calls clearer because they can now make direct updates to CWalletTx entries without having to make temporary objects and then worry about how they will be merged.

  Motivation for this change came from the bumpfee PR #8456 where we wanted to be able to call AddToWallet to make a simple update to an existing transaction, but were reluctant to, because the existing CWalletTx merging logic did not apply and seemed dangerous try to update as part of that PR. After this refactoring, the bumpfee PR could call AddToWallet safely instead of implementing a duplicate AddToWallet function.

  This also allows getting rid of the CWalletTx copy constructor to prevent unintentional copying.

ACKs for top commit:
  MarcoFalke:
    Anyway, re-ACK 28b112e9bd3fd1181c0720306051ba7efca8b436

Tree-SHA512: 528dd088714472a237500b200f4433db850bdb7fc29c5e5d81cae48072061dfb967f7c37edd90b33f24901239f9be982988547c1f8c80abc25fb243fbf7330ef

1 files changed, 37 insertions, 33 deletions

diff --git a/src/wallet/walletdb.cpp b/src/wallet/walletdb.cpp
index 45033f9bac..98597bdb0f 100644
--- a/src/wallet/walletdb.cpp
+++ b/src/wallet/walletdb.cpp
@@ -272,36 +272,43 @@ ReadKeyValue(CWallet* pwallet, CDataStream& ssKey, CDataStream& ssValue,
         } else if (strType == DBKeys::TX) {
             uint256 hash;
             ssKey >> hash;
-            CWalletTx wtx(nullptr /* pwallet */, MakeTransactionRef());
-            ssValue >> wtx;
-            if (wtx.GetHash() != hash)
-                return false;
+            // LoadToWallet call below creates a new CWalletTx that fill_wtx
+            // callback fills with transaction metadata.
+            auto fill_wtx = [&](CWalletTx& wtx, bool new_tx) {
+                assert(new_tx);
+                ssValue >> wtx;
+                if (wtx.GetHash() != hash)
+                    return false;
 
-            // Undo serialize changes in 31600
-            if (31404 <= wtx.fTimeReceivedIsTxTime && wtx.fTimeReceivedIsTxTime <= 31703)
-            {
-                if (!ssValue.empty())
-                {
-                    char fTmp;
-                    char fUnused;
-                    std::string unused_string;
-                    ssValue >> fTmp >> fUnused >> unused_string;
-                    strErr = strprintf("LoadWallet() upgrading tx ver=%d %d %s",
-                                       wtx.fTimeReceivedIsTxTime, fTmp, hash.ToString());
-                    wtx.fTimeReceivedIsTxTime = fTmp;
-                }
-                else
+                // Undo serialize changes in 31600
+                if (31404 <= wtx.fTimeReceivedIsTxTime && wtx.fTimeReceivedIsTxTime <= 31703)
                 {
-                    strErr = strprintf("LoadWallet() repairing tx ver=%d %s", wtx.fTimeReceivedIsTxTime, hash.ToString());
-                    wtx.fTimeReceivedIsTxTime = 0;
+                    if (!ssValue.empty())
+                    {
+                        char fTmp;
+                        char fUnused;
+                        std::string unused_string;
+                        ssValue >> fTmp >> fUnused >> unused_string;
+                        strErr = strprintf("LoadWallet() upgrading tx ver=%d %d %s",
+                                           wtx.fTimeReceivedIsTxTime, fTmp, hash.ToString());
+                        wtx.fTimeReceivedIsTxTime = fTmp;
+                    }
+                    else
+                    {
+                        strErr = strprintf("LoadWallet() repairing tx ver=%d %s", wtx.fTimeReceivedIsTxTime, hash.ToString());
+                        wtx.fTimeReceivedIsTxTime = 0;
+                    }
+                    wss.vWalletUpgrade.push_back(hash);
                 }
-                wss.vWalletUpgrade.push_back(hash);
-            }
 
-            if (wtx.nOrderPos == -1)
-                wss.fAnyUnordered = true;
+                if (wtx.nOrderPos == -1)
+                    wss.fAnyUnordered = true;
 
-            pwallet->LoadToWallet(wtx);
+                return true;
+            };
+            if (!pwallet->LoadToWallet(hash, fill_wtx)) {
+                return false;
+            }
         } else if (strType == DBKeys::WATCHS) {
             wss.nWatchKeys++;
             CScript script;
@@ -731,7 +738,7 @@ DBErrors WalletBatch::LoadWallet(CWallet* pwallet)
     return result;
 }
 
-DBErrors WalletBatch::FindWalletTx(std::vector<uint256>& vTxHash, std::vector<CWalletTx>& vWtx)
+DBErrors WalletBatch::FindWalletTx(std::vector<uint256>& vTxHash, std::list<CWalletTx>& vWtx)
 {
     DBErrors result = DBErrors::LOAD_OK;
 
@@ -769,12 +776,9 @@ DBErrors WalletBatch::FindWalletTx(std::vector<uint256>& vTxHash, std::vector<CW
             if (strType == DBKeys::TX) {
                 uint256 hash;
                 ssKey >> hash;
-
-                CWalletTx wtx(nullptr /* pwallet */, MakeTransactionRef());
-                ssValue >> wtx;
-
                 vTxHash.push_back(hash);
-                vWtx.push_back(wtx);
+                vWtx.emplace_back(nullptr /* wallet */, nullptr /* tx */);
+                ssValue >> vWtx.back();
             }
         }
         pcursor->close();
@@ -793,7 +797,7 @@ DBErrors WalletBatch::ZapSelectTx(std::vector<uint256>& vTxHashIn, std::vector<u
 {
     // build list of wallet TXs and hashes
     std::vector<uint256> vTxHash;
-    std::vector<CWalletTx> vWtx;
+    std::list<CWalletTx> vWtx;
     DBErrors err = FindWalletTx(vTxHash, vWtx);
     if (err != DBErrors::LOAD_OK) {
         return err;
@@ -827,7 +831,7 @@ DBErrors WalletBatch::ZapSelectTx(std::vector<uint256>& vTxHashIn, std::vector<u
     return DBErrors::LOAD_OK;
 }
 
-DBErrors WalletBatch::ZapWalletTx(std::vector<CWalletTx>& vWtx)
+DBErrors WalletBatch::ZapWalletTx(std::list<CWalletTx>& vWtx)
 {
     // build list of wallet TXs
     std::vector<uint256> vTxHash;