Function encode_message

c/examples/send-abort.c:77–110

Create a message with a map { "sequence" : number } encode it and return the encoded buffer. */

/* Create a message with a map { "sequence" : number } encode it and return the encoded buffer. */
static pn_bytes_t encode_message(app_data_t* app) {
  /* Construct a message with the map { "sequence": app.sent } */
  pn_message_t* message = pn_message();
  char data[MSG_SIZE + 11] = {0};
  pn_data_t* body;
  pn_message_set_id(message, (pn_atom_t){.type=PN_ULONG, .u.as_ulong=app->sent});
  body = pn_message_body(message);
  pn_data_enter(body);
  pn_data_put_string(body, pn_bytes(MSG_SIZE, data));
  pn_data_exit(body);

  /* encode the message, expanding the encode buffer as needed */
  if (app->message_buffer.start == NULL) {
    static const size_t initial_size = MSG_SIZE + 1000;
    app->message_buffer = pn_rwbytes(initial_size, (char*)malloc(initial_size));
  }
  /* app->message_buffer is the total buffer space available. */
  /* mbuf wil point at just the portion used by the encoded message */
  {
  pn_rwbytes_t mbuf = pn_rwbytes(app->message_buffer.size, app->message_buffer.start);
  int status = 0;
  while ((status = pn_message_encode(message, mbuf.start, &mbuf.size)) == PN_OVERFLOW) {
    app->message_buffer.size *= 2;
    app->message_buffer.start = (char*)realloc(app->message_buffer.start, app->message_buffer.size);
    mbuf.size = app->message_buffer.size;
  }
  if (status != 0) {
    fprintf(stderr, "error encoding message: %s\n", pn_error_text(pn_message_error(message)));
    exit(1);
  }
  pn_message_free(message);
  return pn_bytes(mbuf.size, mbuf.start);
  }
}

/* Returns true to continue, false if finished */
static bool handle(app_data_t* app, pn_event_t* event) {