7.2 C API Asynchronous Interface Data Structures

This section describes data structures specific to asynchronous C API functions. For information about general-purpose C API data structures, see Section 5.2, “C API Basic Data Structures”.

• enum connect_stage

  Stage of an asynchronous connection. The value may be one of the CONNECT_STAGE_ symbols shown in the following table.

  Enumeration Stage Value	Description
  CONNECT_STAGE_INVALID = 0	MYSQL not valid or an unknown state
  CONNECT_STAGE_NOT_STARTED	Not connected
  CONNECT_STAGE_NET_BEGIN_CONNECT	Begin connection to the server
  CONNECT_STAGE_NET_WAIT_CONNECT	Wait for connection to be established
  CONNECT_STAGE_NET_COMPLETE_CONNECT	Initialize the local data structures post connect
  CONNECT_STAGE_READ_GREETING	Read the first packet
  CONNECT_STAGE_PARSE_HANDSHAKE	Parse the first packet
  CONNECT_STAGE_ESTABLISH_SSL	TLS establishment
  CONNECT_STAGE_AUTHENTICATE	Authentication phase
  CONNECT_STAGE_AUTH_BEGIN	Determine the plugin to use
  CONNECT_STAGE_AUTH_RUN_FIRST_AUTHENTICATE_USER	Run first auth plugin
  CONNECT_STAGE_AUTH_HANDLE_FIRST_AUTHENTICATE_USER	Handle the result of the first authentication plugin run
  CONNECT_STAGE_AUTH_READ_CHANGE_USER_RESULT	Read the implied changed user authentication (if any)
  CONNECT_STAGE_AUTH_HANDLE_CHANGE_USER_REQUEST	Check if server asked to use a different authentication plugin
  CONNECT_STAGE_AUTH_RUN_SECOND_AUTHENTICATE_USER	Start the authentication process again with the plugin requested by the server
  CONNECT_STAGE_AUTH_INIT_MULTI_AUTH	Start multifactor authentication
  CONNECT_STAGE_AUTH_FINISH_AUTH	Final cleanup
  CONNECT_STAGE_AUTH_HANDLE_SECOND_AUTHENTICATE_USER	Now read the results of the second plugin run
  CONNECT_STAGE_AUTH_DO_MULTI_PLUGIN_AUTH	Invoke client plugins multi-auth authentication method
  CONNECT_STAGE_AUTH_HANDLE_MULTI_AUTH_RESPONSE	Handle response from client plugins authentication method
  CONNECT_STAGE_PREP_SELECT_DATABASE	Authenticated, set initial database if specified
  CONNECT_STAGE_PREP_INIT_COMMANDS	Prepare to send a sequence of init commands
  CONNECT_STAGE_SEND_ONE_INIT_COMMAND	Send an init command, which is called once for each init command until they all run (or a failure occurs)
  CONNECT_STAGE_COMPLETE	Connected or no asynchronous connect is in progress

• enum net_async_status

  The enumeration type used to express the return status of asynchronous C API functions. The following table shows the permitted status values.

  Enumeration Status Value	Description
  NET_ASYNC_COMPLETE	Asynchronous operation is complete
  NET_ASYNC_NOT_READY	Asynchronous operation is still in progress
  NET_ASYNC_ERROR	Asynchronous operation terminated in error
  NET_ASYNC_COMPLETE_NO_MORE_RESULTS	For mysql_next_result_nonblocking(); indicates no more results available

  For more information, see Chapter 7, C API Asynchronous Interface.