Merge #15699: Remove no-op CClientUIInterface::[signal_name]_disconnect. Disconnect BlockNotifyGenesisWait and RPCNotifyBlockChange properly.

6dd469a3be Disconnect BlockNotifyGenesisWait and RPCNotifyBlockChange properly. Remove no-op CClientUIInterface::[signal_name]_disconnect. (practicalswift)

Pull request description:

  Resolves #15698.

  Changes:
  * Remove no-op `CClientUIInterface::[signal_name]_disconnect`.
  * Disconnect `BlockNotifyGenesisWait` and `RPCNotifyBlockChange` properly.

ACKs for commit 6dd469:
  MarcoFalke:
    utACK 6dd469a3be

Tree-SHA512: 0b50d658fa72261332bc57ddea379fd08f4bc1de392c10c628e20142d6fd244b606c39fd0665d6bc39324c1aa8c8814ac942b4659106279e33b90206aaf37411

src/init.cpp

@@ -345,14 +345,15 @@ static void registerSignalHandler(int signal, void(*handler)(int))
 }
 #endif
 
+static boost::signals2::connection rpc_notify_block_change_connection;
 static void OnRPCStarted()
 {
-    uiInterface.NotifyBlockTip_connect(&RPCNotifyBlockChange);
+    rpc_notify_block_change_connection = uiInterface.NotifyBlockTip_connect(&RPCNotifyBlockChange);
 }
 
 static void OnRPCStopped()
 {
-    uiInterface.NotifyBlockTip_disconnect(&RPCNotifyBlockChange);
+    rpc_notify_block_change_connection.disconnect();
     RPCNotifyBlockChange(false, nullptr);
     g_best_block_cv.notify_all();
     LogPrint(BCLog::RPC, "RPC stopped.\n");
@@ -1733,8 +1734,9 @@ bool AppInitMain(InitInterfaces& interfaces)
 
     // 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.
+    boost::signals2::connection block_notify_genesis_wait_connection;
     if (chainActive.Tip() == nullptr) {
-        uiInterface.NotifyBlockTip_connect(BlockNotifyGenesisWait);
+        block_notify_genesis_wait_connection = uiInterface.NotifyBlockTip_connect(BlockNotifyGenesisWait);
     } else {
         fHaveGenesis = true;
     }
@@ -1758,7 +1760,7 @@ bool AppInitMain(InitInterfaces& interfaces)
         while (!fHaveGenesis && !ShutdownRequested()) {
             g_genesis_wait_cv.wait_for(lock, std::chrono::milliseconds(500));
         }
-        uiInterface.NotifyBlockTip_disconnect(BlockNotifyGenesisWait);
+        block_notify_genesis_wait_connection.disconnect();
     }
 
     if (ShutdownRequested()) {

src/ui_interface.cpp

@@ -28,10 +28,6 @@ struct UISignals {
     boost::signals2::connection CClientUIInterface::signal_name##_connect(std::function<signal_name##Sig> fn) \
     {                                                                                                         \
         return g_ui_signals.signal_name.connect(fn);                                                          \
-    }                                                                                                         \
-    void CClientUIInterface::signal_name##_disconnect(std::function<signal_name##Sig> fn)                     \
-    {                                                                                                         \
-        return g_ui_signals.signal_name.disconnect(&fn);                                                      \
     }
 
 ADD_SIGNALS_IMPL_WRAPPER(ThreadSafeMessageBox);

src/ui_interface.h

@@ -81,8 +81,7 @@ public:
 #define ADD_SIGNALS_DECL_WRAPPER(signal_name, rtype, ...)                                  \
     rtype signal_name(__VA_ARGS__);                                                        \
     using signal_name##Sig = rtype(__VA_ARGS__);                                           \
-    boost::signals2::connection signal_name##_connect(std::function<signal_name##Sig> fn); \
-    void signal_name##_disconnect(std::function<signal_name##Sig> fn);
+    boost::signals2::connection signal_name##_connect(std::function<signal_name##Sig> fn);
 
     /** Show message box. */
     ADD_SIGNALS_DECL_WRAPPER(ThreadSafeMessageBox, bool, const std::string& message, const std::string& caption, unsigned int style);