Libdrizzle Redux contains functions which give it the capabilities to connect as a MySQL slave or a mysqlbinlog type client and retrieve the events.
Warning
You should start a binlog retrieval on a new connection only. Running on a connection that has already executed queries has an undefined (usually bad) behaviour.
The binlog functions use a callback API so that a function in the user application will be called whenever there is a new event to retrieve.
.. c:type:: drizzle_binlog_st The internal struct containing the binlog stream information
.. c:type:: drizzle_binlog_event_st The internal struct containing the binlog event header and data
There are two callback functions. The first is called whenever a new event is available to retrieve. The second is triggered whenever an error (or EOF) occurs.
.. c:function:: void (drizzle_binlog_fn)(drizzle_binlog_event_st *event, void *context)
This defines the function that will be supplied to accept binlog events
.. warning::
Event data needs to be copied/processed before exiting the function, it
will be erased before the next callback.
:param event: A pointer to the event struct
:param context: A user defined pointer supplied in :c:func:`drizzle_binlog_init`
.. c:function:: void (drizzle_binlog_error_fn)(drizzle_return_t error, drizzle_st *con, void *context) This defines the function that will be supplied to accept binlog errors :param error: The :c:type:`drizzle_return_t` for the error (or :py:const:`DRIZZLE_RETURN_EOF` when all events have been retrieved :param con: The connection object the error occurred on :param context: A user defined pointer supplied in :c:func:`drizzle_binlog_init`
.. c:function:: drizzle_binlog_st *drizzle_binlog_init(drizzle_st *con, drizzle_binlog_fn *binlog_fn, drizzle_binlog_error_fn *error_fn, void *context, bool verify_checksums) Initializes a binlog object for the connection and sets the event callback functions :param con: The connection the binlog retrieval will be on :param binlog_fn: The function callback defined in :c:func:`(drizzle_binlog_fn)` :param error_fn: The function callback defined in :c:func:`(drizzle_binlog_error_fn)` :param context: A pointer to user data which will be used for the callback functions :param verify_checksums: Set to true if MySQL 5.6 and higher checksums should be verified
.. c:function:: void drizzle_binlog_free(drizzle_binlog_st *binlog) Frees a binlog object created with :c:func:`drizzle_binlog_init` :param binlog: The binlog object to be freed
.. c:function:: drizzle_return_t drizzle_binlog_start(drizzle_binlog_st *binlog, uint32_t server_id, const char *file, uint32_t start_position) Start the binlog transaction. Set the server_id to 0 to disconnect automatically at the end of the last log. :param binlog: A binlog object created using :c:func:`drizzle_binlog_init` :param server_id: A unique server ID (or 0) to connect to the MySQL server with :param file: The start binlog file, can be empty to start at the first known file :param start_position: The position of the binlog file to start at, a value of less than 4 is set to 4 due to the binlog header taking the first 4 bytes :returns: A Drizzle return type. :py:const:`DRIZZLE_RETURN_OK` upon success.
.. c:function:: uint32_t drizzle_binlog_event_timestamp(drizzle_binlog_event_st *event) Get the timestamp for the event received by the event callback :param event: The event from the binlog stream :returns: The timestamp for the binlog event
.. c:function:: drizzle_binlog_event_types_t drizzle_binlog_event_type(drizzle_binlog_event_st *event) Get the event type for the event received by the event callback :param event: The event from the binlog stream :returns: The timestamp for the binlog event
.. c:function:: uint32_t drizzle_binlog_event_server_id(drizzle_binlog_event_st *event) Get the server_id for the event received by the event callback :param event: The event from the binlog stream :returns: The server_id for the binlog event
.. c:function:: uint32_t drizzle_binlog_event_length(drizzle_binlog_event_st *event) Get the length of the event data received by the event callback :param event: The event from binlog stream :returns: The event data length
.. c:function:: uint32_t drizzle_binlog_event_next_pos(drizzle_binlog_event_st *event) Get the next event position from the event received by the event callback :param event: The event from the binlog stream :returns: The next event position
.. c:function:: uint16_t drizzle_binlog_event_flags(drizzle_binlog_event_st *event) Get the flags for the event received by the event callback :param event: The event from the binlog stream :returns: The event flags
.. c:function:: uint16_t drizzle_binlog_event_extra_flags(drizzle_binlog_event_st *event) Get the extra flags for the event received by the event callback :param event: The event from the binlog stream :returns: The extra event flags
.. c:function:: const unsigned char* drizzle_binlog_event_data(drizzle_binlog_event_st *event) Get the event data for the event received by the event callback :param event: The event from the binlog stream :returns: A pointer to the event data
.. c:function:: const unsigned char* drizzle_binlog_event_raw_data(drizzle_binlog_event_st *event) Get the raw event data (including header) for the event received by the event callback :param event: The event from the binlog stream :returns: A pointer to the raw event data
.. c:function:: uint32_t drizzle_binlog_event_raw_length(drizzle_binlog_event_st *event) Get the length of the raw event data (including header) for the event received by the event callback :param event: The event from the binlog stream :returns: The length of the raw event data
.. c:function:: const char *drizzle_binlog_event_type_str(drizzle_binlog_event_types_t event_type) Get the event type for the binlog event as string :param event_type: A binlog event type :returns: The event type of the binlog event as string
.. c:function:: void drizzle_binlog_get_filename(drizzle_st *con, char *filename, int file_index) Get the name of a binlog-file Queries the database for a list of binlog files and copies the filename to the passed buffer If the file_index is invalid or no binlog files exist filename will contain an empty string A valid file_index is in the range [-1 to (number of binlog files -1)] The memory (de)allocation of the filename buffer must be done by the client :param con: Drizzle structure previously initialized with :c:func:`drizzle_create` :param filename: Buffer to copy filename to :param file_index: Index of the binlog to retrieve