gstreamer/gst/gstplugin.h
Niels De Graef 09141c6e1f Use G_DEFINE_AUTOPTR_CLEANUP_FUNC unconditionally
Since we started depending on GLib 2.44, we can be sure this macro is
defined (it will be a no-op on compilers that don't support it). For
plugins we should just start using `G_DECLARE_FINAL_TYPE` which means
we no longer need the macro there, but for most types in core we don't
want to break ABI, which means it's better to just keep it like it is
(and use the `#ifdef` instead).
2019-06-04 08:50:59 +02:00

403 lines
14 KiB
C

/* GStreamer
* Copyright (C) 1999,2000 Erik Walthinsen <omega@cse.ogi.edu>
* 2000 Wim Taymans <wtay@chello.be>
*
* gstplugin.h: Header for plugin subsystem
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
* Boston, MA 02110-1301, USA.
*/
#ifndef __GST_PLUGIN_H__
#define __GST_PLUGIN_H__
#include <gst/gstconfig.h>
#include <gst/gstobject.h>
#include <gst/gstmacros.h>
#include <gst/gststructure.h>
G_BEGIN_DECLS
/**
* GstPlugin:
*
* The opaque plugin object
*/
typedef struct _GstPlugin GstPlugin;
typedef struct _GstPluginClass GstPluginClass;
typedef struct _GstPluginDesc GstPluginDesc;
/**
* gst_plugin_error_quark:
*
* Get the error quark.
*
* Returns: The error quark used in GError messages
*/
GST_API
GQuark gst_plugin_error_quark (void);
/**
* GST_PLUGIN_ERROR:
*
* The error message category quark
*/
#define GST_PLUGIN_ERROR gst_plugin_error_quark ()
/**
* GstPluginError:
* @GST_PLUGIN_ERROR_MODULE: The plugin could not be loaded
* @GST_PLUGIN_ERROR_DEPENDENCIES: The plugin has unresolved dependencies
* @GST_PLUGIN_ERROR_NAME_MISMATCH: The plugin has already be loaded from a different file
*
* The plugin loading errors
*/
typedef enum
{
GST_PLUGIN_ERROR_MODULE,
GST_PLUGIN_ERROR_DEPENDENCIES,
GST_PLUGIN_ERROR_NAME_MISMATCH
} GstPluginError;
/**
* GstPluginFlags:
* @GST_PLUGIN_FLAG_CACHED: Temporarily loaded plugins
* @GST_PLUGIN_FLAG_BLACKLISTED: The plugin won't be scanned (again)
*
* The plugin loading state
*/
typedef enum
{
GST_PLUGIN_FLAG_CACHED = (GST_OBJECT_FLAG_LAST << 0),
GST_PLUGIN_FLAG_BLACKLISTED = (GST_OBJECT_FLAG_LAST << 1)
} GstPluginFlags;
/**
* GstPluginDependencyFlags:
* @GST_PLUGIN_DEPENDENCY_FLAG_NONE : no special flags
* @GST_PLUGIN_DEPENDENCY_FLAG_RECURSE : recurse into subdirectories
* @GST_PLUGIN_DEPENDENCY_FLAG_PATHS_ARE_DEFAULT_ONLY : use paths
* argument only if none of the environment variables is set
* @GST_PLUGIN_DEPENDENCY_FLAG_FILE_NAME_IS_SUFFIX : interpret
* filename argument as filter suffix and check all matching files in
* the directory
* @GST_PLUGIN_DEPENDENCY_FLAG_FILE_NAME_IS_PREFIX : interpret
* filename argument as filter prefix and check all matching files in
* the directory. Since: 1.8.
* @GST_PLUGIN_DEPENDENCY_FLAG_PATHS_ARE_RELATIVE_TO_EXE : interpret
* non-absolute paths as relative to the main executable directory. Since
* 1.14.
*
* Flags used in connection with gst_plugin_add_dependency().
*/
typedef enum {
GST_PLUGIN_DEPENDENCY_FLAG_NONE = 0,
GST_PLUGIN_DEPENDENCY_FLAG_RECURSE = (1 << 0),
GST_PLUGIN_DEPENDENCY_FLAG_PATHS_ARE_DEFAULT_ONLY = (1 << 1),
GST_PLUGIN_DEPENDENCY_FLAG_FILE_NAME_IS_SUFFIX = (1 << 2),
GST_PLUGIN_DEPENDENCY_FLAG_FILE_NAME_IS_PREFIX = (1 << 3),
GST_PLUGIN_DEPENDENCY_FLAG_PATHS_ARE_RELATIVE_TO_EXE = (1 << 4)
} GstPluginDependencyFlags;
/**
* GstPluginInitFunc:
* @plugin: The plugin object
*
* A plugin should provide a pointer to a function of this type in the
* plugin_desc struct.
* This function will be called by the loader at startup. One would then
* register each #GstPluginFeature.
*
* Returns: %TRUE if plugin initialised successfully
*/
/* FIXME 0.11: Make return void */
typedef gboolean (*GstPluginInitFunc) (GstPlugin *plugin);
/**
* GstPluginInitFullFunc:
* @plugin: The plugin object
* @user_data: extra data
*
* A plugin should provide a pointer to a function of either #GstPluginInitFunc
* or this type in the plugin_desc struct.
* The function will be called by the loader at startup. One would then
* register each #GstPluginFeature. This version allows
* user data to be passed to init function (useful for bindings).
*
* Returns: %TRUE if plugin initialised successfully
*/
/* FIXME 0.11: Merge with GstPluginInitFunc */
typedef gboolean (*GstPluginInitFullFunc) (GstPlugin *plugin, gpointer user_data);
/**
* GstPluginDesc:
* @major_version: the major version number of core that plugin was compiled for
* @minor_version: the minor version number of core that plugin was compiled for
* @name: a unique name of the plugin
* @description: description of plugin
* @plugin_init: pointer to the init function of this plugin.
* @version: version of the plugin
* @license: effective license of plugin
* @source: source module plugin belongs to
* @package: shipped package plugin belongs to
* @origin: URL to provider of plugin
* @release_datetime: (allow-none): date time string in ISO 8601
* format (or rather, a subset thereof), or %NULL. Allowed are the
* following formats: "YYYY-MM-DD" and "YYY-MM-DDTHH:MMZ" (with
* 'T' a separator and 'Z' indicating UTC/Zulu time). This field
* should be set via the GST_PACKAGE_RELEASE_DATETIME
* preprocessor macro.
*
* A plugin should export a variable of this type called plugin_desc. The plugin
* loader will use the data provided there to initialize the plugin.
*
* The @licence parameter must be one of: LGPL, GPL, QPL, GPL/QPL, MPL,
* BSD, MIT/X11, Proprietary, unknown.
*/
struct _GstPluginDesc {
gint major_version;
gint minor_version;
const gchar *name;
const gchar *description;
GstPluginInitFunc plugin_init;
const gchar *version;
const gchar *license;
const gchar *source;
const gchar *package;
const gchar *origin;
const gchar *release_datetime;
/*< private >*/
gpointer _gst_reserved[GST_PADDING];
};
#define GST_TYPE_PLUGIN (gst_plugin_get_type())
#define GST_IS_PLUGIN(obj) (G_TYPE_CHECK_INSTANCE_TYPE ((obj), GST_TYPE_PLUGIN))
#define GST_IS_PLUGIN_CLASS(klass) (G_TYPE_CHECK_CLASS_TYPE ((klass), GST_TYPE_PLUGIN))
#define GST_PLUGIN_GET_CLASS(obj) (G_TYPE_INSTANCE_GET_CLASS ((obj), GST_TYPE_PLUGIN, GstPluginClass))
#define GST_PLUGIN(obj) (G_TYPE_CHECK_INSTANCE_CAST ((obj), GST_TYPE_PLUGIN, GstPlugin))
#define GST_PLUGIN_CLASS(klass) (G_TYPE_CHECK_CLASS_CAST ((klass), GST_TYPE_PLUGIN, GstPluginClass))
#define GST_PLUGIN_CAST(obj) ((GstPlugin*)(obj))
#ifdef GST_PACKAGE_RELEASE_DATETIME
#define __GST_PACKAGE_RELEASE_DATETIME GST_PACKAGE_RELEASE_DATETIME
#else
#define __GST_PACKAGE_RELEASE_DATETIME NULL
#endif
/**
* GST_PLUGIN_STATIC_DECLARE:
* @name: short, but unique name of the plugin
*
* This macro can be used to initialize statically linked plugins. It is
* necessary to call this macro before the plugin can be used.
* It has to be used in combination with GST_PLUGIN_STATIC_REGISTER
* and must be placed outside any block to declare the plugin initialization
* function.
*
* Since: 1.2
*/
#define GST_PLUGIN_STATIC_DECLARE(name) \
extern void G_PASTE(gst_plugin_, G_PASTE(name, _register)) (void)
/**
* GST_PLUGIN_STATIC_REGISTER:
* @name: short, but unique name of the plugin
*
* This macro can be used to initialize statically linked plugins. It is
* necessary to call this macro before the plugin can be used.
* It has to be used in combination with GST_PLUGIN_STATIC_DECLARE and
* calls the plugin initialization function.
*
* Since: 1.2
*/
#define GST_PLUGIN_STATIC_REGISTER(name) G_PASTE(gst_plugin_, G_PASTE(name, _register)) ()
/**
* GST_PLUGIN_DEFINE:
* @major: major version number of the gstreamer-core that plugin was compiled for
* @minor: minor version number of the gstreamer-core that plugin was compiled for
* @name: short, but unique name of the plugin
* @description: information about the purpose of the plugin
* @init: function pointer to the plugin_init method with the signature of <code>static gboolean plugin_init (GstPlugin * plugin)</code>.
* @version: full version string (e.g. VERSION from config.h)
* @license: under which licence the package has been released, e.g. GPL, LGPL.
* @package: the package-name (e.g. PACKAGE_NAME from config.h)
* @origin: a description from where the package comes from (e.g. the homepage URL)
*
* This macro needs to be used to define the entry point and meta data of a
* plugin. One would use this macro to export a plugin, so that it can be used
* by other applications.
*
* The macro uses a define named PACKAGE for the #GstPluginDesc,source field.
* When using autoconf, this is usually set automatically via the AC_INIT
* macro, and set in config.h. If you are not using autoconf, you will need to
* define PACKAGE yourself and set it to a short mnemonic string identifying
* your application/package, e.g. 'someapp' or 'my-plugins-foo.
*
* If defined, the GST_PACKAGE_RELEASE_DATETIME will also be used for the
* #GstPluginDesc,release_datetime field.
*/
#define GST_PLUGIN_DEFINE(major,minor,name,description,init,version,license,package,origin) \
G_BEGIN_DECLS \
GST_PLUGIN_EXPORT const GstPluginDesc * G_PASTE(gst_plugin_, G_PASTE(name, _get_desc)) (void); \
GST_PLUGIN_EXPORT void G_PASTE(gst_plugin_, G_PASTE(name, _register)) (void); \
\
static const GstPluginDesc gst_plugin_desc = { \
major, \
minor, \
G_STRINGIFY(name), \
(gchar *) description, \
init, \
version, \
license, \
PACKAGE, \
package, \
origin, \
__GST_PACKAGE_RELEASE_DATETIME, \
GST_PADDING_INIT \
}; \
\
const GstPluginDesc * \
G_PASTE(gst_plugin_, G_PASTE(name, _get_desc)) (void) \
{ \
return &gst_plugin_desc; \
} \
\
void \
G_PASTE(gst_plugin_, G_PASTE(name, _register)) (void) \
{ \
gst_plugin_register_static (major, minor, G_STRINGIFY(name), \
description, init, version, license, \
PACKAGE, package, origin); \
} \
G_END_DECLS
/**
* GST_LICENSE_UNKNOWN:
*
* To be used in GST_PLUGIN_DEFINE if unsure about the licence.
*/
#define GST_LICENSE_UNKNOWN "unknown"
/* function for filters */
/**
* GstPluginFilter:
* @plugin: the plugin to check
* @user_data: the user_data that has been passed on e.g. gst_registry_plugin_filter()
*
* A function that can be used with e.g. gst_registry_plugin_filter()
* to get a list of plugins that match certain criteria.
*
* Returns: %TRUE for a positive match, %FALSE otherwise
*/
typedef gboolean (*GstPluginFilter) (GstPlugin *plugin,
gpointer user_data);
GST_API
GType gst_plugin_get_type (void);
GST_API
gboolean gst_plugin_register_static (gint major_version,
gint minor_version,
const gchar *name,
const gchar *description,
GstPluginInitFunc init_func,
const gchar *version,
const gchar *license,
const gchar *source,
const gchar *package,
const gchar *origin);
GST_API
gboolean gst_plugin_register_static_full (gint major_version,
gint minor_version,
const gchar *name,
const gchar *description,
GstPluginInitFullFunc init_full_func,
const gchar *version,
const gchar *license,
const gchar *source,
const gchar *package,
const gchar *origin,
gpointer user_data);
GST_API
const gchar* gst_plugin_get_name (GstPlugin *plugin);
GST_API
const gchar* gst_plugin_get_description (GstPlugin *plugin);
GST_API
const gchar* gst_plugin_get_filename (GstPlugin *plugin);
GST_API
const gchar* gst_plugin_get_version (GstPlugin *plugin);
GST_API
const gchar* gst_plugin_get_license (GstPlugin *plugin);
GST_API
const gchar* gst_plugin_get_source (GstPlugin *plugin);
GST_API
const gchar* gst_plugin_get_package (GstPlugin *plugin);
GST_API
const gchar* gst_plugin_get_origin (GstPlugin *plugin);
GST_API
const gchar* gst_plugin_get_release_date_string (GstPlugin *plugin);
GST_API
const GstStructure* gst_plugin_get_cache_data (GstPlugin * plugin);
GST_API
void gst_plugin_set_cache_data (GstPlugin * plugin, GstStructure *cache_data);
GST_API
gboolean gst_plugin_is_loaded (GstPlugin *plugin);
GST_API
GstPlugin * gst_plugin_load_file (const gchar *filename, GError** error);
GST_API
GstPlugin * gst_plugin_load (GstPlugin *plugin);
GST_API
GstPlugin * gst_plugin_load_by_name (const gchar *name);
GST_API
void gst_plugin_add_dependency (GstPlugin * plugin,
const gchar ** env_vars,
const gchar ** paths,
const gchar ** names,
GstPluginDependencyFlags flags);
GST_API
void gst_plugin_add_dependency_simple (GstPlugin * plugin,
const gchar * env_vars,
const gchar * paths,
const gchar * names,
GstPluginDependencyFlags flags);
GST_API
void gst_plugin_list_free (GList *list);
G_DEFINE_AUTOPTR_CLEANUP_FUNC(GstPlugin, gst_object_unref)
G_END_DECLS
#endif /* __GST_PLUGIN_H__ */