fixes

source/assets/data_loaders/glsl_loader.cpp

@@ -0,0 +1,36 @@
+#include "assets/data_loaders/glsl_loader.hpp"
+
+#include <fstream>
+
+std::error_code glsl_loader::load(
+	const std::filesystem::path& filename,
+	std::string& source
+) {
+
+	auto file = std::ifstream(filename);
+	if (not file.is_open())
+	{
+		return std::make_error_code(std::errc::no_such_file_or_directory);
+	}
+
+	file.seekg(0, std::ios::end);
+	const auto size = file.tellg();
+
+	if (size == 0 or size == std::numeric_limits<std::streamsize>::max())
+	{
+		return std::make_error_code(std::errc::invalid_seek);
+	}
+
+	source.reserve(size);
+
+	file.seekg(0, std::ios::beg);
+
+	source.assign(
+		std::istreambuf_iterator<char>(file),
+		std::istreambuf_iterator<char>()
+	);
+
+	file.close();
+
+	return {};
+}