Merge #11351: Refactor: Modernize disallowed copy constructors/assignment

2a07f878a Refactor: Modernize disallowed copy constructors/assignment (Dan Raviv)

Pull request description:

  Use C++11's better capability of expressing an interface of a non-copyable class by publicly deleting its copy ctor and assignment operator instead of just declaring them private.

Tree-SHA512: 878f446be5a136bb2a90643aaeaca62948b575e6ef71ccc5b4b8f373e66f36ced00665128f36504e0ccfee639863d969329c4276154ef9f2a9de9137f0801e01

src/coins.h

@@ -214,6 +214,11 @@ protected:
 public:
     CCoinsViewCache(CCoinsView *baseIn);
 
+    /**
+     * By deleting the copy constructor, we prevent accidentally using it when one intends to create a cache on top of a base cache.
+     */
+    CCoinsViewCache(const CCoinsViewCache &) = delete;
+
     // Standard CCoinsView methods
     bool GetCoin(const COutPoint &outpoint, Coin &coin) const override;
     bool HaveCoin(const COutPoint &outpoint) const override;
@@ -290,11 +295,6 @@ public:
 
 private:
     CCoinsMap::iterator FetchCoin(const COutPoint &outpoint) const;
-
-    /**
-     * By making the copy constructor private, we prevent accidentally using it when one intends to create a cache on top of a base cache.
-     */
-    CCoinsViewCache(const CCoinsViewCache &);
 };
 
 //! Utility function to add all of a transaction's outputs to a cache.

src/net.h

@@ -895,13 +895,11 @@ public:
 
     CNode(NodeId id, ServiceFlags nLocalServicesIn, int nMyStartingHeightIn, SOCKET hSocketIn, const CAddress &addrIn, uint64_t nKeyedNetGroupIn, uint64_t nLocalHostNonceIn, const CAddress &addrBindIn, const std::string &addrNameIn = "", bool fInboundIn = false);
     ~CNode();
+    CNode(const CNode&) = delete;
+    CNode& operator=(const CNode&) = delete;
 
 private:
-    CNode(const CNode&);
-    void operator=(const CNode&);
     const NodeId id;
-
-
     const uint64_t nLocalHostNonce;
     // Services offered to this peer
     const ServiceFlags nLocalServices;

src/streams.h

@@ -412,10 +412,6 @@ public:
 class CAutoFile
 {
 private:
-    // Disallow copies
-    CAutoFile(const CAutoFile&);
-    CAutoFile& operator=(const CAutoFile&);
-
     const int nType;
     const int nVersion;
 
@@ -432,6 +428,10 @@ public:
         fclose();
     }
 
+    // Disallow copies
+    CAutoFile(const CAutoFile&) = delete;
+    CAutoFile& operator=(const CAutoFile&) = delete;
+
     void fclose()
     {
         if (file) {
@@ -521,10 +521,6 @@ public:
 class CBufferedFile
 {
 private:
-    // Disallow copies
-    CBufferedFile(const CBufferedFile&);
-    CBufferedFile& operator=(const CBufferedFile&);
-
     const int nType;
     const int nVersion;
 
@@ -566,6 +562,10 @@ public:
         fclose();
     }
 
+    // Disallow copies
+    CBufferedFile(const CBufferedFile&) = delete;
+    CBufferedFile& operator=(const CBufferedFile&) = delete;
+
     int GetVersion() const { return nVersion; }
     int GetType() const { return nType; }
 

src/support/lockedpool.h

@@ -50,6 +50,9 @@ public:
     Arena(void *base, size_t size, size_t alignment);
     virtual ~Arena();
 
+    Arena(const Arena& other) = delete; // non construction-copyable
+    Arena& operator=(const Arena&) = delete; // non copyable
+
     /** Memory statistics. */
     struct Stats
     {
@@ -85,9 +88,6 @@ public:
      */
     bool addressInArena(void *ptr) const { return ptr >= base && ptr < end; }
 private:
-    Arena(const Arena& other) = delete; // non construction-copyable
-    Arena& operator=(const Arena&) = delete; // non copyable
-
     /** Map of chunk address to chunk information. This class makes use of the
      * sorted order to merge previous and next chunks during deallocation.
      */
@@ -153,6 +153,9 @@ public:
     explicit LockedPool(std::unique_ptr<LockedPageAllocator> allocator, LockingFailed_Callback lf_cb_in = nullptr);
     ~LockedPool();
 
+    LockedPool(const LockedPool& other) = delete; // non construction-copyable
+    LockedPool& operator=(const LockedPool&) = delete; // non copyable
+
     /** Allocate size bytes from this arena.
      * Returns pointer on success, or 0 if memory is full or
      * the application tried to allocate 0 bytes.
@@ -168,9 +171,6 @@ public:
     /** Get pool usage statistics */
     Stats stats() const;
 private:
-    LockedPool(const LockedPool& other) = delete; // non construction-copyable
-    LockedPool& operator=(const LockedPool&) = delete; // non copyable
-
     std::unique_ptr<LockedPageAllocator> allocator;
 
     /** Create an arena from locked pages */

src/txdb.h

@@ -112,10 +112,10 @@ class CBlockTreeDB : public CDBWrapper
 {
 public:
     explicit CBlockTreeDB(size_t nCacheSize, bool fMemory = false, bool fWipe = false);
-private:
+
-    CBlockTreeDB(const CBlockTreeDB&);
+    CBlockTreeDB(const CBlockTreeDB&) = delete;
-    void operator=(const CBlockTreeDB&);
+    CBlockTreeDB& operator=(const CBlockTreeDB&) = delete;
-public:
+
     bool WriteBatchSync(const std::vector<std::pair<int, const CBlockFileInfo*> >& fileInfo, int nLastFile, const std::vector<const CBlockIndex*>& blockinfo);
     bool ReadBlockFileInfo(int nFile, CBlockFileInfo &fileinfo);
     bool ReadLastBlockFile(int &nFile);

src/wallet/db.h

@@ -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)

src/wallet/walletdb.h

@@ -122,6 +122,8 @@ public:
         m_dbw(dbw)
     {
     }
+    CWalletDB(const CWalletDB&) = delete;
+    CWalletDB& operator=(const CWalletDB&) = delete;
 
     bool WriteName(const std::string& strAddress, const std::string& strName);
     bool EraseName(const std::string& strAddress);
@@ -203,9 +205,6 @@ public:
 private:
     CDB batch;
     CWalletDBWrapper& m_dbw;
-
-    CWalletDB(const CWalletDB&);
-    void operator=(const CWalletDB&);
 };
 
 //! Compacts BDB state so that wallet.dat is self-contained (if there are changes)