working on win32 uwp! and libremidi update

include/libremidi/backends/net/helpers.hpp

@@ -0,0 +1,91 @@
+#pragma once
+#include <libremidi/config.hpp>
+
+#include <boost/asio/ip/udp.hpp>
+
+#include <memory>
+namespace stdx
+{ /*
+
+class boost_system_error_domain : public error_domain
+{
+public:
+  constexpr boost_system_error_domain() noexcept
+      : error_domain{
+            {1 - 0x3c223c0aa3cf45e5ULL, 1 - 0x80dac24345cfb9fcULL},
+            default_error_resource_management_t<detail::exception_ptr_wrapper>{}}
+  {
+  }
+
+  string_ref name() const noexcept override { return "boost::system_error domain"; }
+
+  bool equivalent(const error& lhs, const error& rhs) const noexcept override { return false; }
+
+  string_ref message(const error& e) const noexcept override {
+    auto err = e.m_value;
+    
+  }
+
+  [[noreturn]] void throw_exception(const error& e) const override
+  {
+    assert(e.domain() == *this);
+    std::rethrow_exception(error_cast<detail::exception_ptr_wrapper>(e).get());
+  }
+};
+*/
+}
+
+namespace libremidi
+{
+template <typename T>
+struct optionally_owned
+{
+public:
+  explicit optionally_owned(T* maybe_existing)
+      : storage{.ref = maybe_existing}
+  {
+    if (storage.ref)
+    {
+      ownership = unowned;
+      return;
+    }
+    else
+    {
+      std::destroy_at(&storage.ref);
+      std::construct_at<T>(reinterpret_cast<T*>(storage.object));
+      ownership = owned;
+    }
+  }
+
+  ~optionally_owned()
+  {
+    if (is_owned())
+      std::destroy_at(reinterpret_cast<T*>(storage.object));
+  }
+
+  T& get() noexcept { return *(is_owned() ? reinterpret_cast<T*>(&storage.object) : storage.ref); }
+  const T& get() const noexcept
+  {
+    return *(is_owned() ? reinterpret_cast<T*>(&storage.object) : storage.ref);
+  }
+
+  optionally_owned(const optionally_owned&) = delete;
+  optionally_owned(optionally_owned&&) noexcept = delete;
+  optionally_owned& operator=(const optionally_owned&) = delete;
+  optionally_owned& operator=(optionally_owned&&) noexcept = delete;
+
+  bool is_owned() const noexcept { return ownership == owned; }
+
+private:
+  union
+  {
+    alignas(T) unsigned char object[sizeof(T)];
+    T* ref;
+  } storage;
+  enum
+  {
+    owned,
+    unowned
+  } ownership{};
+};
+}