add rcon packet struct

src/main.c

@@ -8,6 +8,18 @@
 
 const char *LOCALHOST = "127.0.0.1";
 
+#define SERVERDATA_AUTH 3
+#define SERVERDATA_AUTH_RESPONSE 2
+#define SERVERDATA_EXECCOMMAND 2
+#define SERVERDATA_RESPONSE_VALUE 0
+
+typedef struct {
+    int32_t size;
+    int32_t id;
+    int32_t type;
+    char body[4096];
+} rcon_packet_t;
+
 int read_env_int(const char *var) {
     const char* port_str = getenv(var);