Core/Database: Add Empty and CancelAll functions to AsyncCallbackProcessor and enable callback concept check

src/server/database/Database/DatabaseEnvFwd.h

@@ -18,6 +18,7 @@
 #ifndef DatabaseEnvFwd_h__
 #define DatabaseEnvFwd_h__
 
+#include "AsyncCallbackProcessorFwd.h"
 #include <memory>
 
 struct QueryResultFieldMetadata;
@@ -45,9 +46,7 @@ class PreparedResultSet;
 using PreparedQueryResult = std::shared_ptr<PreparedResultSet>;
 
 class QueryCallback;
-
-template<typename T>
-class AsyncCallbackProcessor;
+bool InvokeAsyncCallbackIfReady(QueryCallback& callback);
 
 using QueryCallbackProcessor = AsyncCallbackProcessor<QueryCallback>;
 
@@ -57,6 +56,7 @@ template<typename T>
 class Transaction;
 
 class TransactionCallback;
+bool InvokeAsyncCallbackIfReady(TransactionCallback& callback);
 
 template<typename T>
 using SQLTransaction = std::shared_ptr<Transaction<T>>;
@@ -77,6 +77,7 @@ using LoginDatabaseQueryHolder = SQLQueryHolder<LoginDatabaseConnection>;
 using WorldDatabaseQueryHolder = SQLQueryHolder<WorldDatabaseConnection>;
 
 class SQLQueryHolderCallback;
+bool InvokeAsyncCallbackIfReady(SQLQueryHolderCallback& callback);
 
 // mysql
 struct MySQLHandle;

src/server/database/Database/QueryCallback.h

@@ -57,4 +57,6 @@ private:
     std::queue<QueryCallbackData, std::list<QueryCallbackData>> _callbacks;
 };
 
+inline bool InvokeAsyncCallbackIfReady(QueryCallback& callback) { return callback.InvokeIfReady(); }
+
 #endif // _QUERY_CALLBACK_H

src/server/database/Database/QueryHolder.h

@@ -79,4 +79,6 @@ public:
     std::function<void(SQLQueryHolderBase const&)> m_callback;
 };
 
+inline bool InvokeAsyncCallbackIfReady(SQLQueryHolderCallback& callback) { return callback.InvokeIfReady(); }
+
 #endif

src/server/database/Database/Transaction.h

@@ -122,4 +122,6 @@ public:
     std::function<void(bool)> m_callback;
 };
 
+inline bool InvokeAsyncCallbackIfReady(TransactionCallback& callback) { return callback.InvokeIfReady(); }
+
 #endif