Use explicit way to update calculate SQL length

Author: Artyom Abakumov

src/jrd/trace/TraceDSQLHelpers.h

@@ -55,11 +55,13 @@ class TraceDSQLPrepare
 
 		m_start_clock = fb_utils::query_performance_counter();
 
-		static constexpr std::string_view empty_string = "<empty statement>";
-		if (m_string == nullptr || (m_string_len == 0 && (m_string_len = fb_strlen(m_string)) == 0))
+		if (m_string == nullptr)
+			traceEmptyStatement();
+		else if (m_string_len == 0)
 		{
-			m_string = empty_string.data();
-			m_string_len = empty_string.length();
+			m_string_len = fb_strlen(m_string);
+			if (m_string_len == 0)
+				traceEmptyStatement();
 		}
 	}
 
@@ -105,6 +107,13 @@ class TraceDSQLPrepare
 	}
 
 private:
+	void traceEmptyStatement()
+	{
+		static constexpr std::string_view empty_string = "<empty statement>";
+		m_string = empty_string.data();
+		m_string_len = empty_string.length();
+	}
+
 	bool m_need_trace;
 	Attachment* m_attachment;
 	jrd_tra* const m_transaction;