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

1 files changed, 3 insertions, 3 deletions

diff --git a/src/zmq/zmqnotificationinterface.cpp b/src/zmq/zmqnotificationinterface.cpp
index c063898056..b637f26fb2 100644
--- a/src/zmq/zmqnotificationinterface.cpp
+++ b/src/zmq/zmqnotificationinterface.cpp
@@ -15,7 +15,7 @@ void zmqError(const char *str)
     LogPrint(BCLog::ZMQ, "zmq: Error: %s, errno=%s\n", str, zmq_strerror(errno));
 }
 
-CZMQNotificationInterface::CZMQNotificationInterface() : pcontext(NULL)
+CZMQNotificationInterface::CZMQNotificationInterface() : pcontext(nullptr)
 {
 }
 
@@ -31,7 +31,7 @@ CZMQNotificationInterface::~CZMQNotificationInterface()
 
 CZMQNotificationInterface* CZMQNotificationInterface::Create()
 {
-    CZMQNotificationInterface* notificationInterface = NULL;
+    CZMQNotificationInterface* notificationInterface = nullptr;
     std::map<std::string, CZMQNotifierFactory> factories;
     std::list<CZMQAbstractNotifier*> notifiers;
 
@@ -62,7 +62,7 @@ CZMQNotificationInterface* CZMQNotificationInterface::Create()
         if (!notificationInterface->Initialize())
         {
             delete notificationInterface;
-            notificationInterface = NULL;
+            notificationInterface = nullptr;
         }
     }