Object resources

The object resource functions tie resource allocation to an instance of a module through a VLC object. More...

Collaboration diagram for Object resources:

Macros
#define	vlc_obj_malloc(o, s)   vlc_obj_malloc(VLC_OBJECT(o), s)
#define	vlc_obj_calloc(o, n, s)   vlc_obj_calloc(VLC_OBJECT(o), n, s)
#define	vlc_obj_strdup(o, s)   vlc_obj_strdup(VLC_OBJECT(o), s)
#define	vlc_obj_free(o, p)   vlc_obj_free(VLC_OBJECT(o), p)

Functions
void *	vlc_obj_malloc (_Generic((vlc_object_t *obj) ->obj, struct vlc_object_marker *:(vlc_object_t *obj), default:(&((vlc_object_t *obj) ->obj))), size_t size)
	Allocates memory for a module. More...
void *	vlc_obj_calloc (_Generic((vlc_object_t *obj) ->obj, struct vlc_object_marker *:(vlc_object_t *obj), default:(&((vlc_object_t *obj) ->obj))), size_t nmemb, size_t size)
	Allocates a zero-initialized table for a module. More...
char *	vlc_obj_strdup (_Generic((vlc_object_t *obj) ->obj, struct vlc_object_marker *:(vlc_object_t *obj), default:(&((vlc_object_t *obj) ->obj))), const char *str)
	Duplicates a string for a module. More...
void	vlc_obj_free (_Generic((vlc_object_t *obj) ->obj, struct vlc_object_marker *:(vlc_object_t *obj), default:(&((vlc_object_t *obj) ->obj))), void *ptr)
	Manually frees module memory. More...

Detailed Description

The object resource functions tie resource allocation to an instance of a module through a VLC object.

Such resource will be automatically freed, in first in last out order, when the module instance associated with the VLC object is terminated.

Specifically, if the module instance activation/probe function fails, the resource will be freed immediately after the failure. If the activation succeeds, the resource will be freed when the module instance is terminated.

This is a convenience mechanism to save explicit clean-up function calls in modules.

Macro Definition Documentation

vlc_obj_calloc

#define vlc_obj_calloc	(		o,
			n,
			s
	)		vlc_obj_calloc(VLC_OBJECT(o), n, s)

vlc_obj_free

#define vlc_obj_free	(		o,
			p
	)		vlc_obj_free(VLC_OBJECT(o), p)

vlc_obj_malloc

#define vlc_obj_malloc	(		o,
			s
	)		vlc_obj_malloc(VLC_OBJECT(o), s)

vlc_obj_strdup

#define vlc_obj_strdup	(		o,
			s
	)		vlc_obj_strdup(VLC_OBJECT(o), s)

Function Documentation

vlc_obj_calloc()

void * vlc_obj_calloc	(	_Generic((vlc_object_t *obj) ->obj, struct vlc_object_marker *:(vlc_object_t *obj), default:(&((vlc_object_t *obj) ->obj)))	,
		size_t	nmemb,
		size_t	size
	)

Allocates a zero-initialized table for a module.

This function allocates a table from the heap for a module instance. The memory is initialized to all zeroes.

Parameters

obj	VLC object to tie the memory allocation to
nmemb	number of table entries
size	byte size of a table entry

Returns

a pointer to the allocated memory, or NULL on error (errno is set).

vlc_obj_free()

void vlc_obj_free	(	_Generic((vlc_object_t *obj) ->obj, struct vlc_object_marker *:(vlc_object_t *obj), default:(&((vlc_object_t *obj) ->obj)))	,
		void *	ptr
	)

Manually frees module memory.

This function manually frees a resource allocated with vlc_obj_malloc(), vlc_obj_calloc() or vlc_obj_strdup() before the module instance is terminated. This is seldom necessary.

Parameters

obj	VLC object that the allocation was tied to
ptr	pointer to the allocated resource

vlc_obj_malloc()

void * vlc_obj_malloc	(	_Generic((vlc_object_t *obj) ->obj, struct vlc_object_marker *:(vlc_object_t *obj), default:(&((vlc_object_t *obj) ->obj)))	,
		size_t	size
	)

Allocates memory for a module.

This function allocates memory from the heap for a module instance. The memory is uninitialized.

Parameters

obj	VLC object to tie the memory allocation to
size	byte size of the memory allocation

Returns

a pointer to the allocated memory, or NULL on error (errno is set).

vlc_obj_strdup()

char * vlc_obj_strdup	(	_Generic((vlc_object_t *obj) ->obj, struct vlc_object_marker *:(vlc_object_t *obj), default:(&((vlc_object_t *obj) ->obj)))	,
		const char *	str
	)

Duplicates a string for a module.

This function allocates a copy of a nul-terminated string for a module instance.

Parameters

obj	VLC object to tie the memory allocation to
str	string to copy

Returns

a pointer to the copy, or NULL on error (errno is set).