Add binary deserialization helper class

libs/util/include/psemek/util/binary_stream.hpp

@@ -0,0 +1,86 @@
+#pragma once
+
+#include <string_view>
+#include <stdexcept>
+
+#include <vector>
+
+namespace psemek::util
+{
+
+	namespace detail
+	{
+
+		inline void unexpected_end()
+		{
+			throw std::runtime_error("Unexpected binary stream end");
+		}
+
+		template <typename T>
+		struct read_helper
+		{
+			static_assert(std::is_trivially_copyable_v<T>);
+
+			static T read(std::string_view & data)
+			{
+				if (data.size() < sizeof(T))
+					unexpected_end();
+
+				T value;
+				std::copy(data.data(), data.data() + sizeof(T), reinterpret_cast<char *>(std::addressof(value)));
+				data.remove_prefix(sizeof(T));
+				return value;
+			}
+		};
+
+		template <typename T>
+		struct read_helper<std::vector<T>>
+		{
+			static T read(std::string_view & data)
+			{
+				std::uint32_t size = read_helper<std::uint32_t>::read(data);
+
+				std::vector<T> result;
+
+				if constexpr (std::is_trivially_copyable_v<T>)
+				{
+					if (data.size() < sizeof(T) * size)
+						unexpected_end();
+
+					result.resize(size);
+					std::copy(data.data(), data.data() + sizeof(T) * size, reinterpret_cast<char *>(result.data()));
+				}
+				else
+				{
+					for (std::uint32_t i = 0; i < size; ++i)
+						result.push_back(read_helper<T>::read(data));
+				}
+
+				return result;
+			}
+		};
+
+	}
+
+	struct binary_istream
+	{
+		std::string_view data;
+
+		template <typename T>
+		T read()
+		{
+			return detail::read_helper<T>::read(data);
+		}
+
+		char const * read_raw(std::size_t count)
+		{
+			if (data.size() < count)
+				detail::unexpected_end();
+
+			auto p = data.data();
+			data.remove_prefix(count);
+			return p;
+		}
+	};
+
+}