LookupServer: Port to LibCore

Servers/LookupServer/LookupServer.h

@@ -0,0 +1,36 @@
+#pragma once
+
+#include <AK/HashMap.h>
+#include <AK/RefPtr.h>
+#include <AK/String.h>
+#include <LibCore/CObject.h>
+
+class CLocalSocket;
+class CLocalServer;
+
+class LookupServer final : public CObject {
+    C_OBJECT(LookupServer)
+
+public:
+    LookupServer();
+
+private:
+    void load_etc_hosts();
+    void service_client(RefPtr<CLocalSocket>);
+    static String parse_dns_name(const u8* data, int& offset, int max_offset);
+    Vector<String> lookup(const String& hostname, bool& did_timeout, unsigned short record_type);
+
+    u16 get_next_id() { return ++m_next_id; }
+
+    struct CachedLookup {
+        time_t timestamp { 0 };
+        unsigned short record_type { 0 };
+        Vector<String> responses;
+    };
+
+    RefPtr<CLocalServer> m_local_server;
+    u16 m_next_id { 0 };
+    String m_dns_ip;
+    HashMap<String, String> m_dns_custom_hostnames;
+    HashMap<String, CachedLookup> m_lookup_cache;
+};