walletdb: Add MakeBatch function to BerkeleyDatabase and use it

Instead of having WalletBatch construct the BerkeleyBatch, have
BerkeleyDatabase do it and return a std::unique_ptr<BerkeleyBatch>

src/wallet/bdb.cpp

@@ -841,3 +841,8 @@ bool BerkeleyBatch::HasKey(CDataStream&& key)
     int ret = pdb->exists(activeTxn, datKey, 0);
     return ret == 0;
 }
+
+std::unique_ptr<BerkeleyBatch> BerkeleyDatabase::MakeBatch(const char* mode, bool flush_on_close)
+{
+    return MakeUnique<BerkeleyBatch>(*this, mode, flush_on_close);
+}

src/wallet/bdb.h

@@ -93,6 +93,8 @@ std::shared_ptr<BerkeleyEnvironment> GetWalletEnv(const fs::path& wallet_path, s
 /** Return wheter a BDB wallet database is currently loaded. */
 bool IsBDBWalletLoaded(const fs::path& wallet_path);
 
+class BerkeleyBatch;
+
 /** An instance of this class represents one database.
  * For BerkeleyDB this is just a (env, strFile) tuple.
  **/
@@ -161,6 +163,9 @@ public:
     /** Database pointer. This is initialized lazily and reset during flushes, so it can be null. */
     std::unique_ptr<Db> m_db;
 
+    /** Make a BerkeleyBatch connected to this database */
+    std::unique_ptr<BerkeleyBatch> MakeBatch(const char* mode, bool flush_on_close);
+
 private:
     std::string strFile;
 

src/wallet/walletdb.cpp

@@ -121,7 +121,7 @@ bool WalletBatch::WriteCryptedKey(const CPubKey& vchPubKey,
     if (!WriteIC(key, std::make_pair(vchCryptedSecret, checksum), false)) {
         // It may already exist, so try writing just the checksum
         std::vector<unsigned char> val;
-        if (!m_batch.Read(key, val)) {
+        if (!m_batch->Read(key, val)) {
             return false;
         }
         if (!WriteIC(key, std::make_pair(val, checksum), true)) {
@@ -166,8 +166,8 @@ bool WalletBatch::WriteBestBlock(const CBlockLocator& locator)
 
 bool WalletBatch::ReadBestBlock(CBlockLocator& locator)
 {
-    if (m_batch.Read(DBKeys::BESTBLOCK, locator) && !locator.vHave.empty()) return true;
+    if (m_batch->Read(DBKeys::BESTBLOCK, locator) && !locator.vHave.empty()) return true;
-    return m_batch.Read(DBKeys::BESTBLOCK_NOMERKLE, locator);
+    return m_batch->Read(DBKeys::BESTBLOCK_NOMERKLE, locator);
 }
 
 bool WalletBatch::WriteOrderPosNext(int64_t nOrderPosNext)
@@ -177,7 +177,7 @@ bool WalletBatch::WriteOrderPosNext(int64_t nOrderPosNext)
 
 bool WalletBatch::ReadPool(int64_t nPool, CKeyPool& keypool)
 {
-    return m_batch.Read(std::make_pair(DBKeys::POOL, nPool), keypool);
+    return m_batch->Read(std::make_pair(DBKeys::POOL, nPool), keypool);
 }
 
 bool WalletBatch::WritePool(int64_t nPool, const CKeyPool& keypool)
@@ -693,14 +693,14 @@ DBErrors WalletBatch::LoadWallet(CWallet* pwallet)
     LOCK(pwallet->cs_wallet);
     try {
         int nMinVersion = 0;
-        if (m_batch.Read(DBKeys::MINVERSION, nMinVersion)) {
+        if (m_batch->Read(DBKeys::MINVERSION, nMinVersion)) {
             if (nMinVersion > FEATURE_LATEST)
                 return DBErrors::TOO_NEW;
             pwallet->LoadMinVersion(nMinVersion);
         }
 
         // Get cursor
-        if (!m_batch.StartCursor())
+        if (!m_batch->StartCursor())
         {
             pwallet->WalletLogPrintf("Error getting wallet database cursor\n");
             return DBErrors::CORRUPT;
@@ -712,13 +712,13 @@ DBErrors WalletBatch::LoadWallet(CWallet* pwallet)
             CDataStream ssKey(SER_DISK, CLIENT_VERSION);
             CDataStream ssValue(SER_DISK, CLIENT_VERSION);
             bool complete;
-            bool ret = m_batch.ReadAtCursor(ssKey, ssValue, complete);
+            bool ret = m_batch->ReadAtCursor(ssKey, ssValue, complete);
             if (complete) {
                 break;
             }
             else if (!ret)
             {
-                m_batch.CloseCursor();
+                m_batch->CloseCursor();
                 pwallet->WalletLogPrintf("Error reading next record from wallet database\n");
                 return DBErrors::CORRUPT;
             }
@@ -748,7 +748,7 @@ DBErrors WalletBatch::LoadWallet(CWallet* pwallet)
     } catch (...) {
         result = DBErrors::CORRUPT;
     }
-    m_batch.CloseCursor();
+    m_batch->CloseCursor();
 
     // Set the active ScriptPubKeyMans
     for (auto spk_man_pair : wss.m_active_external_spks) {
@@ -785,7 +785,7 @@ DBErrors WalletBatch::LoadWallet(CWallet* pwallet)
 
     // Last client version to open this wallet, was previously the file version number
     int last_client = CLIENT_VERSION;
-    m_batch.Read(DBKeys::VERSION, last_client);
+    m_batch->Read(DBKeys::VERSION, last_client);
 
     int wallet_version = pwallet->GetVersion();
     pwallet->WalletLogPrintf("Wallet File Version = %d\n", wallet_version > 0 ? wallet_version : last_client);
@@ -810,7 +810,7 @@ DBErrors WalletBatch::LoadWallet(CWallet* pwallet)
         return DBErrors::NEED_REWRITE;
 
     if (last_client < CLIENT_VERSION) // Update
-        m_batch.Write(DBKeys::VERSION, CLIENT_VERSION);
+        m_batch->Write(DBKeys::VERSION, CLIENT_VERSION);
 
     if (wss.fAnyUnordered)
         result = pwallet->ReorderTransactions();
@@ -846,13 +846,13 @@ DBErrors WalletBatch::FindWalletTx(std::vector<uint256>& vTxHash, std::list<CWal
 
     try {
         int nMinVersion = 0;
-        if (m_batch.Read(DBKeys::MINVERSION, nMinVersion)) {
+        if (m_batch->Read(DBKeys::MINVERSION, nMinVersion)) {
             if (nMinVersion > FEATURE_LATEST)
                 return DBErrors::TOO_NEW;
         }
 
         // Get cursor
-        if (!m_batch.StartCursor())
+        if (!m_batch->StartCursor())
         {
             LogPrintf("Error getting wallet database cursor\n");
             return DBErrors::CORRUPT;
@@ -864,11 +864,11 @@ DBErrors WalletBatch::FindWalletTx(std::vector<uint256>& vTxHash, std::list<CWal
             CDataStream ssKey(SER_DISK, CLIENT_VERSION);
             CDataStream ssValue(SER_DISK, CLIENT_VERSION);
             bool complete;
-            bool ret = m_batch.ReadAtCursor(ssKey, ssValue, complete);
+            bool ret = m_batch->ReadAtCursor(ssKey, ssValue, complete);
             if (complete) {
                 break;
             } else if (!ret) {
-                m_batch.CloseCursor();
+                m_batch->CloseCursor();
                 LogPrintf("Error reading next record from wallet database\n");
                 return DBErrors::CORRUPT;
             }
@@ -886,7 +886,7 @@ DBErrors WalletBatch::FindWalletTx(std::vector<uint256>& vTxHash, std::list<CWal
     } catch (...) {
         result = DBErrors::CORRUPT;
     }
-    m_batch.CloseCursor();
+    m_batch->CloseCursor();
 
     return result;
 }
@@ -999,17 +999,17 @@ bool WalletBatch::WriteWalletFlags(const uint64_t flags)
 
 bool WalletBatch::TxnBegin()
 {
-    return m_batch.TxnBegin();
+    return m_batch->TxnBegin();
 }
 
 bool WalletBatch::TxnCommit()
 {
-    return m_batch.TxnCommit();
+    return m_batch->TxnCommit();
 }
 
 bool WalletBatch::TxnAbort()
 {
-    return m_batch.TxnAbort();
+    return m_batch->TxnAbort();
 }
 
 bool IsWalletLoaded(const fs::path& wallet_path)

src/wallet/walletdb.h

@@ -183,12 +183,12 @@ private:
     template <typename K, typename T>
     bool WriteIC(const K& key, const T& value, bool fOverwrite = true)
     {
-        if (!m_batch.Write(key, value, fOverwrite)) {
+        if (!m_batch->Write(key, value, fOverwrite)) {
             return false;
         }
         m_database.IncrementUpdateCounter();
         if (m_database.nUpdateCounter % 1000 == 0) {
-            m_batch.Flush();
+            m_batch->Flush();
         }
         return true;
     }
@@ -196,19 +196,19 @@ private:
     template <typename K>
     bool EraseIC(const K& key)
     {
-        if (!m_batch.Erase(key)) {
+        if (!m_batch->Erase(key)) {
             return false;
         }
         m_database.IncrementUpdateCounter();
         if (m_database.nUpdateCounter % 1000 == 0) {
-            m_batch.Flush();
+            m_batch->Flush();
         }
         return true;
     }
 
 public:
     explicit WalletBatch(WalletDatabase& database, const char* pszMode = "r+", bool _fFlushOnClose = true) :
-        m_batch(database, pszMode, _fFlushOnClose),
+        m_batch(database.MakeBatch(pszMode, _fFlushOnClose)),
         m_database(database)
     {
     }
@@ -280,7 +280,7 @@ public:
     //! Abort current transaction
     bool TxnAbort();
 private:
-    BerkeleyBatch m_batch;
+    std::unique_ptr<BerkeleyBatch> m_batch;
     WalletDatabase& m_database;
 };