Merge #10483: scripted-diff: Use the C++11 keyword nullptr to denote the pointer literal instead of the macro NULL

90d4d89 scripted-diff: Use the C++11 keyword nullptr to denote the pointer literal instead of the macro NULL (practicalswift)

Pull request description:

  Since C++11 the macro `NULL` may be:
  * an integer literal with value zero, or
  * a prvalue of type `std::nullptr_t`

  By using the C++11 keyword `nullptr` we are guaranteed a prvalue of type `std::nullptr_t`.

  For a more thorough discussion, see "A name for the null pointer: nullptr" (Sutter &
  Stroustrup), http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2007/n2431.pdf

  With this patch applied there are no `NULL` macro usages left in the repo:

  ```
  $ git grep NULL -- "*.cpp" "*.h" | egrep -v '(/univalue/|/secp256k1/|/leveldb/|_NULL|NULLDUMMY|torcontrol.*NULL|NULL cert)' | wc -l
  0
  ```

  The road towards `nullptr` (C++11) is split into two PRs:
  * `NULL` → `nullptr` is handled in PR #10483 (scripted, this PR)
  * `0` → `nullptr` is handled in PR #10645 (manual)

Tree-SHA512: 3c395d66f2ad724a8e6fed74b93634de8bfc0c0eafac94e64e5194c939499fefd6e68f047de3083ad0b4eff37df9a8a3a76349aa17d55eabbd8e0412f140a297

src/init.cpp

@@ -76,7 +76,7 @@ std::unique_ptr<CConnman> g_connman;
 std::unique_ptr<PeerLogicValidation> peerLogic;
 
 #if ENABLE_ZMQ
-static CZMQNotificationInterface* pzmqNotificationInterface = NULL;
+static CZMQNotificationInterface* pzmqNotificationInterface = nullptr;
 #endif
 
 #ifdef WIN32
@@ -153,7 +153,7 @@ public:
     // Writes do not need similar protection, as failure to write is handled by the caller.
 };
 
-static CCoinsViewErrorCatcher *pcoinscatcher = NULL;
+static CCoinsViewErrorCatcher *pcoinscatcher = nullptr;
 static std::unique_ptr<ECCVerifyHandle> globalVerifyHandle;
 
 void Interrupt(boost::thread_group& threadGroup)
@@ -232,17 +232,17 @@ void Shutdown()
 
     {
         LOCK(cs_main);
-        if (pcoinsTip != NULL) {
+        if (pcoinsTip != nullptr) {
             FlushStateToDisk();
         }
         delete pcoinsTip;
-        pcoinsTip = NULL;
+        pcoinsTip = nullptr;
         delete pcoinscatcher;
-        pcoinscatcher = NULL;
+        pcoinscatcher = nullptr;
         delete pcoinsdbview;
-        pcoinsdbview = NULL;
+        pcoinsdbview = nullptr;
         delete pblocktree;
-        pblocktree = NULL;
+        pblocktree = nullptr;
     }
 #ifdef ENABLE_WALLET
     for (CWalletRef pwallet : vpwallets) {
@@ -254,7 +254,7 @@ void Shutdown()
     if (pzmqNotificationInterface) {
         UnregisterValidationInterface(pzmqNotificationInterface);
         delete pzmqNotificationInterface;
-        pzmqNotificationInterface = NULL;
+        pzmqNotificationInterface = nullptr;
     }
 #endif
 
@@ -300,7 +300,7 @@ static void registerSignalHandler(int signal, void(*handler)(int))
     sa.sa_handler = handler;
     sigemptyset(&sa.sa_mask);
     sa.sa_flags = 0;
-    sigaction(signal, &sa, NULL);
+    sigaction(signal, &sa, nullptr);
 }
 #endif
 
@@ -558,7 +558,7 @@ static CConditionVariable condvar_GenesisWait;
 
 static void BlockNotifyGenesisWait(bool, const CBlockIndex *pBlockIndex)
 {
-    if (pBlockIndex != NULL) {
+    if (pBlockIndex != nullptr) {
         {
             boost::unique_lock<boost::mutex> lock_GenesisWait(cs_GenesisWait);
             fHaveGenesis = true;
@@ -843,7 +843,7 @@ bool AppInitBasicSetup()
 #ifdef _MSC_VER
     // Turn off Microsoft heap dump noise
     _CrtSetReportMode(_CRT_WARN, _CRTDBG_MODE_FILE);
-    _CrtSetReportFile(_CRT_WARN, CreateFileA("NUL", GENERIC_WRITE, 0, NULL, OPEN_EXISTING, 0, 0));
+    _CrtSetReportFile(_CRT_WARN, CreateFileA("NUL", GENERIC_WRITE, 0, nullptr, OPEN_EXISTING, 0, 0));
     // Disable confusing "helpful" text message on abort, Ctrl-C
     _set_abort_behavior(0, _WRITE_ABORT_MSG | _CALL_REPORTFAULT);
 #endif
@@ -858,7 +858,7 @@ bool AppInitBasicSetup()
 #endif
     typedef BOOL (WINAPI *PSETPROCDEPPOL)(DWORD);
     PSETPROCDEPPOL setProcDEPPol = (PSETPROCDEPPOL)GetProcAddress(GetModuleHandleA("Kernel32.dll"), "SetProcessDEPPolicy");
-    if (setProcDEPPol != NULL) setProcDEPPol(PROCESS_DEP_ENABLE);
+    if (setProcDEPPol != nullptr) setProcDEPPol(PROCESS_DEP_ENABLE);
 #endif
 
     if (!SetupNetworking())
@@ -1477,7 +1477,7 @@ bool AppInitMain(boost::thread_group& threadGroup, CScheduler& scheduler)
                         strLoadError = _("Error initializing block database");
                         break;
                     }
-                    assert(chainActive.Tip() != NULL);
+                    assert(chainActive.Tip() != nullptr);
                 }
 
                 if (!fReset) {
@@ -1604,7 +1604,7 @@ bool AppInitMain(boost::thread_group& threadGroup, CScheduler& scheduler)
 
     // Either install a handler to notify us when genesis activates, or set fHaveGenesis directly.
     // No locking, as this happens before any background thread is started.
-    if (chainActive.Tip() == NULL) {
+    if (chainActive.Tip() == nullptr) {
         uiInterface.NotifyBlockTip.connect(BlockNotifyGenesisWait);
     } else {
         fHaveGenesis = true;