1 files changed, 161 insertions, 0 deletions
diff --git a/src/libutil/cxx/error.hxx b/src/libutil/cxx/error.hxx
new file mode 100644
index 0000000..4689d42
--- /dev/null
+++ b/src/libutil/cxx/error.hxx
@@ -0,0 +1,161 @@
+/*
+ * Copyright 2024 Vsevolod Stakhov
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef RSPAMD_ERROR_HXX
+#define RSPAMD_ERROR_HXX
+#pragma once
+
+#include "config.h"
+#include <string>
+#include <string_view>
+#include <cstdint>
+#include <optional>
+
+/***
+ * This unit is used to represent Rspamd C++ errors in a way to interoperate
+ * with C code if needed and avoid allocations for static strings
+ */
+namespace rspamd::util {
+
+enum class error_category : std::uint8_t {
+	INFORMAL,
+	IMPORTANT,
+	CRITICAL
+};
+
+struct error {
+public:
+	/**
+	 * Construct from a static string, this string must live long enough to outlive this object
+	 * @param msg
+	 * @param code
+	 * @param category
+	 */
+	error(const char *msg, int code, error_category category = error_category::INFORMAL)
+		: error_message(msg), error_code(code), category(category)
+	{
+	}
+	/**
+	 * Construct error from a temporary string taking membership
+	 * @param msg
+	 * @param code
+	 * @param category
+	 */
+	error(std::string &&msg, int code, error_category category = error_category::INFORMAL)
+		: error_code(code), category(category)
+	{
+		static_storage = std::move(msg);
+		error_message = static_storage.value();
+	}
+	/**
+	 * Construct error from another string copying it into own storage
+	 * @param msg
+	 * @param code
+	 * @param category
+	 */
+	error(const std::string &msg, int code, error_category category = error_category::INFORMAL)
+		: error_code(code), category(category)
+	{
+		static_storage = msg;
+		error_message = static_storage.value();
+	}
+
+	error(const error &other)
+		: error_code(other.error_code), category(other.category)
+	{
+		if (other.static_storage) {
+			static_storage = other.static_storage;
+			error_message = static_storage.value();
+		}
+		else {
+			error_message = other.error_message;
+		}
+	}
+
+	error(error &&other) noexcept
+	{
+		*this = std::move(other);
+	}
+
+	error &operator=(error &&other) noexcept
+	{
+		if (other.static_storage.has_value()) {
+			std::swap(static_storage, other.static_storage);
+			error_message = static_storage.value();
+		}
+		else {
+			std::swap(error_message, other.error_message);
+		}
+		std::swap(other.error_code, error_code);
+		std::swap(other.category, category);
+
+		return *this;
+	}
+
+	/**
+	 * Convert into GError
+	 * @return
+	 */
+	auto into_g_error() const -> GError *
+	{
+		return g_error_new(g_quark_from_static_string("rspamd"), error_code, "%s",
+						   error_message.data());
+	}
+
+	/**
+	 * Convenience alias for the `into_g_error`
+	 * @param err
+	 */
+	auto into_g_error_set(GError **err) const -> void
+	{
+		if (err && *err == nullptr) {
+			*err = into_g_error();
+		}
+	}
+
+	/**
+	 * Convert into GError
+	 * @return
+	 */
+	auto into_g_error(GQuark quark) const -> GError *
+	{
+		return g_error_new(quark, error_code, "%s",
+						   error_message.data());
+	}
+
+	/**
+	 * Convenience alias for the `into_g_error`
+	 * @param err
+	 */
+	auto into_g_error_set(GQuark quark, GError **err) const -> void
+	{
+		if (err && *err == nullptr) {
+			*err = into_g_error(quark);
+		}
+	}
+
+public:
+	std::string_view error_message;
+	int error_code;
+	error_category category;
+
+private:
+	std::optional<std::string> static_storage;
+};
+
+}// namespace rspamd::util
+
+#endif//RSPAMD_ERROR_HXX