Typedefs
typedef struct vlc_log_t	libvlc_log_t

typedef void(*	libvlc_log_cb )(void data, int level, const libvlc_log_t ctx, const char *fmt, va_list args)

Enumerations
enum	libvlc_log_level { LIBVLC_DEBUG =0, LIBVLC_NOTICE =2, LIBVLC_WARNING =3, LIBVLC_ERROR =4 }

Functions
LIBVLC_API void	libvlc_log_get_context (const libvlc_log_t ctx, const char module, const char file, unsigned line)

LIBVLC_API void	libvlc_log_get_object (const libvlc_log_t ctx, const char name, const char header, uintptr_t id)

LIBVLC_API void	libvlc_log_unset (libvlc_instance_t *)

LIBVLC_API void	libvlc_log_set (libvlc_instance_t , libvlc_log_cb cb, void data)

LIBVLC_API void	libvlc_log_set_file (libvlc_instance_t , FILE stream)

LIBVLC_DEPRECATED LIBVLC_API unsigned	libvlc_get_log_verbosity (const libvlc_instance_t *p_instance)

LIBVLC_DEPRECATED LIBVLC_API void	libvlc_set_log_verbosity (libvlc_instance_t *p_instance, unsigned level)

LIBVLC_DEPRECATED LIBVLC_API libvlc_log_t *	libvlc_log_open (libvlc_instance_t *p_instance)

LIBVLC_DEPRECATED LIBVLC_API void	libvlc_log_close (libvlc_log_t *p_log)

LIBVLC_DEPRECATED LIBVLC_API unsigned	libvlc_log_count (const libvlc_log_t *p_log)

LIBVLC_DEPRECATED LIBVLC_API void	libvlc_log_clear (libvlc_log_t *p_log)

LIBVLC_DEPRECATED LIBVLC_API libvlc_log_iterator_t *	libvlc_log_get_iterator (const libvlc_log_t *p_log)

LIBVLC_DEPRECATED LIBVLC_API void	libvlc_log_iterator_free (libvlc_log_iterator_t *p_iter)

LIBVLC_DEPRECATED LIBVLC_API int	libvlc_log_iterator_has_next (const libvlc_log_iterator_t *p_iter)

LIBVLC_DEPRECATED LIBVLC_API libvlc_log_message_t *	libvlc_log_iterator_next (libvlc_log_iterator_t p_iter, libvlc_log_message_t p_buf)

typedef struct libvlc_log_iterator_t	libvlc_log_iterator_t

typedef struct libvlc_log_message_t	libvlc_log_message_t

Detailed Description

libvlc_log_* functions provide access to the LibVLC messages log. This is used for logging and debugging.

Typedef Documentation

typedef void(* libvlc_log_cb)(void *data, int level, const libvlc_log_t *ctx, const char *fmt, va_list args)

Callback prototype for LibVLC log message handler.

Parameters

data	data pointer as given to libvlc_log_set()
level	message level (enum libvlc_log_level)
ctx	message context (meta-informations about the message)
fmt	printf() format string (as defined by ISO C11)
args	variable argument list for the format

Note: Log message handlers must be thread-safe.

Warning: The message context pointer, the format string parameters and the variable arguments are only valid until the callback returns.

typedef struct libvlc_log_iterator_t libvlc_log_iterator_t

This structure is opaque. It represents a libvlc log iterator

Enumeration Type Documentation

enum libvlc_log_level

Logging messages level.

Note: Future LibVLC versions may define new levels.

Enumerator
LIBVLC_DEBUG	Debug message
LIBVLC_NOTICE	Important informational message
LIBVLC_WARNING	Warning (potential error) message
LIBVLC_ERROR	Error message

Function Documentation

LIBVLC_DEPRECATED LIBVLC_API unsigned libvlc_get_log_verbosity ( const libvlc_instance_t * p_instance )

Always returns minus one. This function is only provided for backward compatibility.

Parameters

p_instance ignored

Returns: always -1

LIBVLC_DEPRECATED LIBVLC_API void libvlc_log_clear ( libvlc_log_t * p_log )

This function does nothing. It is only provided for backward compatibility.

Parameters

p_log ignored

LIBVLC_DEPRECATED LIBVLC_API void libvlc_log_close ( libvlc_log_t * p_log )

Frees memory allocated by libvlc_log_open().

Parameters

p_log libvlc log instance or NULL

LIBVLC_DEPRECATED LIBVLC_API unsigned libvlc_log_count ( const libvlc_log_t * p_log )

Always returns zero. This function is only provided for backward compatibility.

Parameters

p_log ignored

Returns: always zero

LIBVLC_API void libvlc_log_get_context	(	const libvlc_log_t *	ctx,
		const char **	module,
		const char **	file,
		unsigned *	line
	)

Gets debugging informations about a log message: the name of the VLC module emitting the message and the message location within the source code.

The returned module name and file name will be NULL if unknown. The returned line number will similarly be zero if unknown.

Parameters

ctx	message context (as passed to the libvlc_log_cb callback)
module	module name storage (or NULL) [OUT]
file	source code file name storage (or NULL) [OUT]
line	source code file line number storage (or NULL) [OUT]

Warning: The returned module name and source code file name, if non-NULL, are only valid until the logging callback returns.

Version: LibVLC 2.1.0 or later

LIBVLC_DEPRECATED LIBVLC_API libvlc_log_iterator_t* libvlc_log_get_iterator ( const libvlc_log_t * p_log )

This function does nothing useful. It is only provided for backward compatibility.

Parameters

p_log ignored

Returns: an unique pointer or NULL on error or if the parameter was NULL

LIBVLC_API void libvlc_log_get_object	(	const libvlc_log_t *	ctx,
		const char **	name,
		const char **	header,
		uintptr_t *	id
	)

Gets VLC object informations about a log message: the type name of the VLC object emitting the message, the object header if any and a temporaly-unique object identifier. These informations are mainly meant for manual troubleshooting.

The returned type name may be "generic" if unknown, but it cannot be NULL. The returned header will be NULL if unset; in current versions, the header is used to distinguish for VLM inputs. The returned object ID will be zero if the message is not associated with any VLC object.

Parameters

ctx	message context (as passed to the libvlc_log_cb callback)
name	object name storage (or NULL) [OUT]
header	object header (or NULL) [OUT]
line	source code file line number storage (or NULL) [OUT]

Warning: The returned module name and source code file name, if non-NULL, are only valid until the logging callback returns.

Version: LibVLC 2.1.0 or later

LIBVLC_DEPRECATED LIBVLC_API void libvlc_log_iterator_free ( libvlc_log_iterator_t * p_iter )

Frees memory allocated by libvlc_log_get_iterator().

Parameters

p_iter libvlc log iterator or NULL

LIBVLC_DEPRECATED LIBVLC_API int libvlc_log_iterator_has_next ( const libvlc_log_iterator_t * p_iter )

Always returns zero. This function is only provided for backward compatibility.

Parameters

p_iter ignored

Returns: always zero

LIBVLC_DEPRECATED LIBVLC_API libvlc_log_message_t* libvlc_log_iterator_next	(	libvlc_log_iterator_t *	p_iter,
		libvlc_log_message_t *	p_buf
	)

Always returns NULL. This function is only provided for backward compatibility.

Parameters

p_iter	libvlc log iterator or NULL
p_buf	ignored

Returns: always NULL

LIBVLC_DEPRECATED LIBVLC_API libvlc_log_t* libvlc_log_open ( libvlc_instance_t * p_instance )

This function does nothing useful. It is only provided for backward compatibility.

Parameters

p_instance libvlc instance

Returns: an unique pointer or NULL on error

LIBVLC_API void libvlc_log_set	(	libvlc_instance_t *	,
		libvlc_log_cb	cb,
		void *	data
	)

Sets the logging callback for a LibVLC instance. This function is thread-safe: it will wait for any pending callbacks invocation to complete.

Parameters

cb	callback function pointer
data	opaque data pointer for the callback function

Note: Some log messages (especially debug) are emitted by LibVLC while is being initialized. These messages cannot be captured with this interface.

Warning: A deadlock may occur if this function is called from the callback.

Parameters

p_instance libvlc instance

Version: LibVLC 2.1.0 or later

LIBVLC_API void libvlc_log_set_file	(	libvlc_instance_t *	,
		FILE *	stream
	)

Sets up logging to a file.

Parameters

p_instance	libvlc instance
stream	FILE pointer opened for writing (the FILE pointer must remain valid until libvlc_log_unset())

Version: LibVLC 2.1.0 or later

LIBVLC_API void libvlc_log_unset ( libvlc_instance_t * )

Unsets the logging callback for a LibVLC instance. This is rarely needed: the callback is implicitly unset when the instance is destroyed. This function will wait for any pending callbacks invocation to complete (causing a deadlock if called from within the callback).

Parameters

p_instance libvlc instance

Version: LibVLC 2.1.0 or later

LIBVLC_DEPRECATED LIBVLC_API void libvlc_set_log_verbosity	(	libvlc_instance_t *	p_instance,
		unsigned	level
	)

This function does nothing. It is only provided for backward compatibility.

Parameters

p_instance	ignored
level	ignored

Typedefs

Enumerations

Functions

Detailed Description

Typedef Documentation

Enumeration Type Documentation

Function Documentation