1 files changed, 16 insertions, 17 deletions

diff --git a/src/wallet/db.h b/src/wallet/db.h
index 4f3ad0c42d..14283ac8f8 100644
--- a/src/wallet/db.h
+++ b/src/wallet/db.h
@@ -45,7 +45,7 @@ public:
     void Reset();
 
     void MakeMock();
-    bool IsMock() { return fMockDb; }
+    bool IsMock() const { return fMockDb; }
 
     /**
      * Verify that database file strFile is OK. If it is not,
@@ -77,10 +77,10 @@ public:
 
     DbTxn* TxnBegin(int flags = DB_TXN_WRITE_NOSYNC)
     {
-        DbTxn* ptxn = NULL;
-        int ret = dbenv->txn_begin(NULL, &ptxn, flags);
+        DbTxn* ptxn = nullptr;
+        int ret = dbenv->txn_begin(nullptr, &ptxn, flags);
         if (!ptxn || ret != 0)
-            return NULL;
+            return nullptr;
         return ptxn;
     }
 };
@@ -156,6 +156,9 @@ public:
     explicit CDB(CWalletDBWrapper& dbw, const char* pszMode = "r+", bool fFlushOnCloseIn=true);
     ~CDB() { Close(); }
 
+    CDB(const CDB&) = delete;
+    CDB& operator=(const CDB&) = delete;
+
     void Flush();
     void Close();
     static bool Recover(const std::string& filename, void *callbackDataIn, bool (*recoverKVcallback)(void* callbackData, CDataStream ssKey, CDataStream ssValue), std::string& out_backup_filename);
@@ -168,10 +171,6 @@ public:
     /* verifies the database file */
     static bool VerifyDatabaseFile(const std::string& walletFile, const fs::path& dataDir, std::string& warningStr, std::string& errorStr, CDBEnv::recoverFunc_type recoverFunc);
 
-private:
-    CDB(const CDB&);
-    void operator=(const CDB&);
-
 public:
     template <typename K, typename T>
     bool Read(const K& key, T& value)
@@ -191,7 +190,7 @@ public:
         int ret = pdb->get(activeTxn, &datKey, &datValue, 0);
         memory_cleanse(datKey.get_data(), datKey.get_size());
         bool success = false;
-        if (datValue.get_data() != NULL) {
+        if (datValue.get_data() != nullptr) {
             // Unserialize value
             try {
                 CDataStream ssValue((char*)datValue.get_data(), (char*)datValue.get_data() + datValue.get_size(), SER_DISK, CLIENT_VERSION);
@@ -282,11 +281,11 @@ public:
     Dbc* GetCursor()
     {
         if (!pdb)
-            return NULL;
-        Dbc* pcursor = NULL;
-        int ret = pdb->cursor(NULL, &pcursor, 0);
+            return nullptr;
+        Dbc* pcursor = nullptr;
+        int ret = pdb->cursor(nullptr, &pcursor, 0);
         if (ret != 0)
-            return NULL;
+            return nullptr;
         return pcursor;
     }
 
@@ -306,7 +305,7 @@ public:
         int ret = pcursor->get(&datKey, &datValue, fFlags);
         if (ret != 0)
             return ret;
-        else if (datKey.get_data() == NULL || datValue.get_data() == NULL)
+        else if (datKey.get_data() == nullptr || datValue.get_data() == nullptr)
             return 99999;
 
         // Convert to streams
@@ -342,7 +341,7 @@ public:
         if (!pdb || !activeTxn)
             return false;
         int ret = activeTxn->commit(0);
-        activeTxn = NULL;
+        activeTxn = nullptr;
         return (ret == 0);
     }
 
@@ -351,7 +350,7 @@ public:
         if (!pdb || !activeTxn)
             return false;
         int ret = activeTxn->abort();
-        activeTxn = NULL;
+        activeTxn = nullptr;
         return (ret == 0);
     }
 
@@ -366,7 +365,7 @@ public:
         return Write(std::string("version"), nVersion);
     }
 
-    bool static Rewrite(CWalletDBWrapper& dbw, const char* pszSkip = NULL);
+    bool static Rewrite(CWalletDBWrapper& dbw, const char* pszSkip = nullptr);
 };
 
 #endif // BITCOIN_WALLET_DB_H