Addon for event and I/O tracing

Typedefs
typedef enum M_io_trace_type	M_io_trace_type_t
typedef void(*	M_io_trace_cb_t) (void *cb_arg, M_io_trace_type_t type, M_event_type_t event_type, const unsigned char *data, size_t data_len)
typedef void *(*	M_io_trace_cb_dup_t) (void *cb_arg)
typedef void(*	M_io_trace_cb_free_t) (void *cb_arg)

Enumerations
enum	M_io_trace_type {   M_IO_TRACE_TYPE_READ = 1 ,   M_IO_TRACE_TYPE_WRITE = 2 ,   M_IO_TRACE_TYPE_EVENT = 3 }

Functions
M_io_error_t	M_io_add_trace (M_io_t *io, size_t *layer_id, M_io_trace_cb_t callback, void *cb_arg, M_io_trace_cb_dup_t cb_dup, M_io_trace_cb_free_t cb_free)
void *	M_io_trace_get_callback_arg (M_io_t *io, size_t layer_id)
M_bool	M_io_trace_set_callback_arg (M_io_t *io, size_t layer_id, void *cb_arg)

Detailed Description

Event and I/O tracing addon

Allows data to be traced as it flows through the trace layer. For example communication over serial with an external device could have a trace layer that logs read and write commands.

This can be very useful when combined with the M_log logging module.

Typedef Documentation

M_io_trace_type_t

typedef enum M_io_trace_type M_io_trace_type_t

M_io_trace_cb_t

typedef void(* M_io_trace_cb_t) (void *cb_arg, M_io_trace_type_t type, M_event_type_t event_type, const unsigned char *data, size_t data_len)

Definition for a function callback that is called every time a traceable event is triggered by the event subsystem.

Parameters

[in]	cb_arg	User-specified callback argument registered when the trace was added to the event handle.
[in]	type	The type of type that has been triggered, see M_io_trace_type_t.
[in]	event_type	The type of event that has been triggered, see M_event_type_t.
[in]	data	Data that is passing though this trace layer.
[in]	data_len	Length of data.

M_io_trace_cb_dup_t

typedef void *(* M_io_trace_cb_dup_t) (void *cb_arg)

Definition for a function that duplicates a callback argument.

An io that has an accept event such as net can have connection specific arguments. The trace layer will be duplicated from the server to the new io client connection. This allows the cb_arg to be duplicated as well.

Parameters

[in]

cb_arg

Callback argument of the type provided to M_io_add_trace.

M_io_trace_cb_free_t

typedef void(* M_io_trace_cb_free_t) (void *cb_arg)

Definition for a function that destroys a user provided callback data associated with the trace.

Parameters

[in]

cb_arg

Callback argument of the type provided to M_io_add_trace.

Enumeration Type Documentation

M_io_trace_type

enum M_io_trace_type

Trace even type.

Enumerator
M_IO_TRACE_TYPE_READ
M_IO_TRACE_TYPE_WRITE
M_IO_TRACE_TYPE_EVENT

Function Documentation

M_io_add_trace()

M_io_error_t M_io_add_trace	(	M_io_t *	io,
		size_t *	layer_id,
		M_io_trace_cb_t	callback,
		void *	cb_arg,
		M_io_trace_cb_dup_t	cb_dup,
		M_io_trace_cb_free_t	cb_free
	)

Add a trace layer

Parameters

[in]	io	io object.
[out]	layer_id	Layer id this is added at.
[in]	callback	Function called when the trace is triggered.
[in]	cb_arg	Argument passed to callback.
[in]	cb_dup	Function to duplicate cb_arg if needed. Optional and can be NULL if not used.
[in]	cb_free	Function to destroy cb_arg when the io object id destroyed. Optional and can be NULL if not used.

Returns

Result.

M_io_trace_get_callback_arg()

void * M_io_trace_get_callback_arg	(	M_io_t *	io,
		size_t	layer_id
	)

Get the callback arg for a trace layer.

Parameters

[in]	io	io object.
[in]	layer_id	Layer id.

Returns

Argument on success or NULL on error. NULL is success if a cb_arg was not set.

M_io_trace_set_callback_arg()

M_bool M_io_trace_set_callback_arg	(	M_io_t *	io,
		size_t	layer_id,
		void *	cb_arg
	)

Set the callback arg for the trace layer.

Parameters

[in]	io	io object.
[in]	layer_id	Layer id.
[in]	cb_arg	Argument passed to callback.

Returns

M_TRUE on success, otherwise M_FALSE on error.