json_connection: keep pointer to the conn.

This is required for our next hack.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

lightningd/jsonrpc.c

@@ -621,6 +621,7 @@ static struct io_plan *jcon_connected(struct io_conn *conn,
 	struct json_connection *jcon;
 
 	jcon = tal(conn, struct json_connection);
+	jcon->conn = conn;
 	jcon->ld = ld;
 	jcon->used = 0;
 	jcon->buffer = tal_arr(jcon, char, 64);

lightningd/jsonrpc.h

@@ -50,6 +50,9 @@ struct json_connection {
 	/* The global state */
 	struct lightningd *ld;
 
+	/* This io_conn (and our owner!) */
+	struct io_conn *conn;
+
 	/* Logging for this json connection. */
 	struct log *log;