Add CopiedString and LinkedString

src/ArduinoJson/Strings/StoredString.hpp

@@ -0,0 +1,32 @@
+// ArduinoJson - https://arduinojson.org
+// Copyright Benoit Blanchon 2014-2021
+// MIT License
+
+#pragma once
+
+#include <ArduinoJson/Polyfills/safe_strcmp.hpp>
+#include <ArduinoJson/Strings/StoragePolicy.hpp>
+
+namespace ARDUINOJSON_NAMESPACE {
+
+template <typename TStoragePolicy>
+class StoredString {
+ public:
+  StoredString(const char* p) : _data(p) {}
+
+  operator const char*() const {
+    return _data;
+  }
+
+  const char* c_str() const {
+    return _data;
+  }
+
+ private:
+  const char* _data;
+};
+
+typedef StoredString<storage_policies::store_by_address> LinkedString;
+typedef StoredString<storage_policies::store_by_copy> CopiedString;
+
+}  // namespace ARDUINOJSON_NAMESPACE