feat: add alignment

include/sp/protocol/Field.h

@@ -5,13 +5,68 @@
 
 namespace sp {
 
-template <typename ValueType>
+/**
+ * \brief Example usage :
+ * sp::BitField<std::uint16_t, sp::Field<std::uint16_t, 12>, sp::Field<std::uint8_t, 4>>;
+ */
+template <typename TContainer, typename... TFields>
+class BitField {
+	using AllFields = std::tuple<TFields...>;
+
+  public:
+	template <typename... T>
+	BitField(const std::tuple<T...>& args) {
+		Apply<0, T...>(args);
+	}
+
+	BitField() {}
+
+	template <typename... T>
+	BitField& operator=(const std::tuple<T...>& args) {
+		Apply<0, T...>(args);
+		return *this;
+	}
+
+	AllFields& GetFields() {
+		return m_Fields;
+	}
+
+	const AllFields& GetFields() const {
+		return m_Fields;
+	}
+
+	template <std::size_t FIndex>
+	auto& GetField() {
+		return std::get<FIndex>(this->GetFields()).GetValue();
+	}
+
+  private:
+	template <int IOffset, typename... T, std::enable_if_t<IOffset >= sizeof...(T), bool> = true>
+	void Apply(const std::tuple<T...>& args) {}
+
+	template <int IOffset, typename... T, std::enable_if_t<!(IOffset >= sizeof...(T)), bool> = true>
+	void Apply(const std::tuple<T...>& args) {
+		this->GetField<IOffset>() = std::get<IOffset>(args);
+		Apply<1 + IOffset, T...>(args);
+	}
+
+	TContainer m_Value;
+	AllFields m_Fields;
+};
+
+/**
+ *
+ * \tparam ValueType the type of the value to store
+ * \tparam IAlignment 0 means no alignment
+ */
+template <typename ValueType, int IAlignment>
 class Field {
   public:
 	// Provide an access to the stored value
 	ValueType& GetValue() {
 		return m_Value;
 	}
+
 	const ValueType& GetValue() const {
 		return m_Value;
 	}
@@ -21,6 +76,10 @@ class Field {
 		return *this;
 	}
 
+	constexpr int GetAlignment() const {
+		return IAlignment;
+	}
+
   private:
 	ValueType m_Value;
 };
@@ -42,7 +101,7 @@ struct FieldsBuilder<std::tuple<TFields...>> {
 
 template <typename TField, typename... TFields>
 struct FieldsBuilder<TField, TFields...> {
-	using Type = sp::tuple_cat_t<std::tuple<Field<TField>>, typename FieldsBuilder<TFields...>::Type>;
+	using Type = sp::tuple_cat_t<std::tuple<Field<TField, 0>>, typename FieldsBuilder<TFields...>::Type>;
 };
 }  // namespace details