From ef7320496046bd4086e1e6a1cc93301ceffe2f5a Mon Sep 17 00:00:00 2001
From: sowle <crypto.sowle@gmail.com>
Date: Wed, 17 Jul 2024 19:43:53 +0200
Subject: [PATCH] added support for std::optional to src/serialization and
 boost serialization

---
 .../keyvalue_serialization_overloads.h        | 23 ++++++++
 src/serialization/boost_types.h               | 55 ++++++++++++++++++-
 2 files changed, 77 insertions(+), 1 deletion(-)

diff --git a/contrib/epee/include/serialization/keyvalue_serialization_overloads.h b/contrib/epee/include/serialization/keyvalue_serialization_overloads.h
index cb88897f..23ad8fce 100644
--- a/contrib/epee/include/serialization/keyvalue_serialization_overloads.h
+++ b/contrib/epee/include/serialization/keyvalue_serialization_overloads.h
@@ -473,6 +473,29 @@ namespace epee
       return r;
     }
     //-------------------------------------------------------------------------------------------------------------------
+    //std::optional 
+    template<class t_type, class t_storage>
+    bool kv_serialize(const std::optional<t_type>& d, t_storage& stg, typename t_storage::hsection hparent_section, const char* pname)
+    {
+      if(d.has_value())
+      {
+        return kv_serialize(*d, stg, hparent_section, pname);
+      }
+      return true;
+    }
+    //-------------------------------------------------------------------------------------------------------------------
+    template<class t_type, class t_storage>
+    bool kv_unserialize(std::optional<t_type>& d, t_storage& stg, typename t_storage::hsection hparent_section, const char* pname)
+    {
+      d = t_type{};
+      bool r = kv_unserialize(*d, stg, hparent_section, pname);
+      if (!r)
+      {
+        d = std::nullopt;
+      }
+      return r;
+    }
+    //-------------------------------------------------------------------------------------------------------------------
     //boost::shared_ptr 
     template<class t_type, class t_storage>
     bool kv_serialize(const boost::shared_ptr<t_type>& d, t_storage& stg, typename t_storage::hsection hparent_section, const char* pname)
diff --git a/src/serialization/boost_types.h b/src/serialization/boost_types.h
index 154705b8..ca3e3d7b 100644
--- a/src/serialization/boost_types.h
+++ b/src/serialization/boost_types.h
@@ -1,3 +1,4 @@
+// Copyright (c) 2018-2024 Zano Project
 // Copyright (c) 2014-2017 The The Louisdor Project
 // Copyright (c) 2012-2013 The Cryptonote developers
 // Distributed under the MIT/X11 software license, see the accompanying
@@ -7,7 +8,7 @@
 
 #include <boost/serialization/optional.hpp>
 
-
+// boost::optional
 template <template <bool> class Archive, class T>
 bool do_serialize(Archive<false> &ar, boost::optional<T> &o)
 {
@@ -58,3 +59,55 @@ bool do_serialize(Archive<true> &ar, boost::optional<T> &v)
 
   return true;
 }
+
+// std::optional
+template <template <bool> class Archive, class T>
+bool do_serialize(Archive<false> &ar, std::optional<T> &o)
+{
+  //reading flag
+  bool is_none = false;
+  if (!::do_serialize(ar, is_none))
+  {
+    ar.stream().setstate(std::ios::failbit);
+    return false;
+  }
+  if (is_none)
+  {
+    o.reset();
+    return true;
+  }
+  o = T();
+  T& rval = o.value();
+  //reading value
+  if (!::do_serialize(ar, rval))
+  {
+    ar.stream().setstate(std::ios::failbit);
+    return false;
+  }
+
+  return true;
+}
+
+template <template <bool> class Archive, class T>
+bool do_serialize(Archive<true> &ar, std::optional<T> &v)
+{
+  //writing flag
+  bool is_none = !v.has_value();
+  if (!::do_serialize(ar, is_none))
+  {
+    ar.stream().setstate(std::ios::failbit);
+    return false;
+  }
+  if (is_none)
+  {
+    return true;
+  }
+
+  if (!::do_serialize(ar, v.value()))
+  {
+    ar.stream().setstate(std::ios::failbit);
+    return false;
+  }
+
+  return true;
+}