Added merge mining RPC client

Basic code and one API call implemented

src/merge_mining_client.h

@@ -0,0 +1,59 @@
+/*
+ * This file is part of the Monero P2Pool <https://github.com/SChernykh/p2pool>
+ * Copyright (c) 2021-2023 SChernykh <https://github.com/SChernykh>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, version 3.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#pragma once
+
+#include "uv_util.h"
+
+namespace p2pool {
+
+class p2pool;
+
+class MergeMiningClient
+{
+public:
+	MergeMiningClient(p2pool* pool, const std::string& host);
+	~MergeMiningClient();
+
+private:
+	static void loop(void* data);
+
+	void merge_mining_get_chain_id();
+	bool parse_merge_mining_get_chain_id(const char* data, size_t size);
+
+	std::string m_host;
+	uint32_t m_port;
+
+	hash m_chainID;
+
+	p2pool* m_pool;
+
+	uv_loop_t m_loop;
+	uv_thread_t m_loopThread;
+
+	uv_async_t m_shutdownAsync;
+
+	static void on_shutdown(uv_async_t* async)
+	{
+		MergeMiningClient* client = reinterpret_cast<MergeMiningClient*>(async->data);
+		uv_close(reinterpret_cast<uv_handle_t*>(&client->m_shutdownAsync), nullptr);
+
+		delete GetLoopUserData(&client->m_loop, false);
+	}
+};
+
+} // namespace p2pool