Should copy the data for async ncurl cases

Author: shikokuchuo

src/ncurl.c

@@ -354,7 +354,7 @@ SEXP rnng_ncurl_aio(SEXP http, SEXP convert, SEXP method, SEXP headers, SEXP dat
   }
   if (data != R_NilValue) {
     nano_buf enc = nano_char_buf(data);
-    if (enc.cur && (xc = nng_http_req_set_data(handle->req, enc.buf, enc.cur)))
+    if (enc.cur && (xc = nng_http_req_copy_data(handle->req, enc.buf, enc.cur)))
       goto fail;
   }
 
@@ -559,7 +559,7 @@ SEXP rnng_ncurl_session(SEXP http, SEXP convert, SEXP method, SEXP headers, SEXP
   }
   if (data != R_NilValue) {
     nano_buf enc = nano_char_buf(data);
-    if (enc.cur && (xc = nng_http_req_set_data(handle->req, enc.buf, enc.cur)))
+    if (enc.cur && (xc = nng_http_req_copy_data(handle->req, enc.buf, enc.cur)))
       goto fail;
   }