grabber_common.h File Reference

#include <pthread.h>
#include <string.h>
#include "stats.h"
#include "utils.h"

Go to the source code of this file.

Data Structures
struct	grabber_param_t
	Structure for the init of a grabber. More...
struct	grabber_list_t
	Structure for a grabber. More...
Defines
#define	GRABBER_REGISTER(p_name, p_caps, p_pl, p_tw,fct_priv, fct_init, fct_uninit, fct_grab, fct_loop)
	Macro to register and populate a grabber structure.
Flags for the capabilities of the grabbers.
#define	GRABBER_CAP_AUDIO   (1 << 0)
	grab for audio files
#define	GRABBER_CAP_VIDEO   (1 << 1)
	grab for video files
#define	GRABBER_CAP_IMAGE   (1 << 2)
	grab for image files

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Detailed Description

GeeXboX Valhalla Grabber private API header.

To add a new grabber, a good approach is to copy an existing grabber like grabber_dummy.[ch] in order to have at least the structure. A grabber must not use global/static variables. A grabber must be thread-safe in the case where more than one instance of Valhalla are running concurrently. But, the functions in one grabber are not called in concurrency in one instance of Valhalla.

Some others points to consider:

• grabber_list_t::init() and grabber_list_t::uninit() functions are called only one time by a Valhalla instance.
• grabber_list_t::grab() function is called only between the grabber_list_t::init() and grabber_list_t::uninit() functions.
• grabber_list_t::loop() function is called only between two scanner loops. The function is not called if only one loop is configured for the instance of Valhalla.

Some utils are available for the grabbers:

• grabber_utils.h utils specific to grabbers
• xml_utils.h for XML parsing (based on libxml2)
• url_utils.h for downloading (based on libcurl)
• logs.h for logging
• md5.h to compute the MD5 sum
• list.h to handle very simple linked-lists

Main header for all grabbers:

• grabber_common.h
  • metadata.h to save metadata retrieved by grabber_list_t::grab()
  • utils.h to prepare files (images, ...) for downloading

See also:

grabber_list_t for details on the functions.

Definition in file grabber_common.h.

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Define Documentation

#define GRABBER_CAP_AUDIO   (1 << 0)

grab for audio files

Definition at line 71 of file grabber_common.h.

#define GRABBER_CAP_IMAGE   (1 << 2)

grab for image files

Definition at line 73 of file grabber_common.h.

#define GRABBER_CAP_VIDEO   (1 << 1)

grab for video files

Definition at line 72 of file grabber_common.h.

#define GRABBER_REGISTER	(		p_name,
			p_caps,
			p_pl,
			p_tw,
			fct_priv,
			fct_init,
			fct_uninit,
			fct_grab,
			fct_loop
	)

Macro to register and populate a grabber structure.

See struct grabber_list_s for more informations on the structure and the functions.

Parameters:

[in]	p_name	Grabber's name.
[in]	p_caps	Capabilities flags.
[in]	p_pl	List of metadata priorities.
[in]	p_tw	Min time to wait [ms] between grabber_list_t::grab().
[in]	fct_priv	Function to retrieve the private data pointer.
[in]	fct_init	grabber_list_t::init().
[in]	fct_uninit	grabber_list_t::uninit().
[in]	fct_grab	grabber_list_t::grab().
[in]	fct_loop	grabber_list_t::loop().

Definition at line 209 of file grabber_common.h.