gstreamer/ges/ges-asset.c
Thibault Saunier 724418b75d assets: Avoid deadlock when done initialising asset
Avoid to hold the CACHE lock when setting the GTasks return values.

Fixes https://bugzilla.gnome.org/show_bug.cgi?id=752300
2015-07-13 13:54:35 +02:00

1031 lines
30 KiB
C

/* GStreamer Editing Services
*
* Copyright (C) 2012 Thibault Saunier <thibault.saunier@collabora.com>
* Copyright (C) 2012 Volodymyr Rudyi <vladimir.rudoy@gmail.com>
*
* 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., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
/**
* SECTION: gesasset
* @short_description: Represents usable resources inside the GStreamer Editing Services
*
* The Assets in the GStreamer Editing Services represent the resources
* that can be used. You can create assets for any type that implements the #GESExtractable
* interface, for example #GESClips, #GESFormatter, and #GESTrackElement do implement it.
* This means that assets will represent for example a #GESUriClips, #GESBaseEffect etc,
* and then you can extract objects of those types with the appropriate parameters from the asset
* using the #ges_asset_extract method:
*
* |[
* GESAsset *effect_asset;
* GESEffect *effect;
*
* // You create an asset for an effect
* effect_asset = ges_asset_request (GES_TYPE_EFFECT, "agingtv", NULL);
*
* // And now you can extract an instance of GESEffect from that asset
* effect = GES_EFFECT (ges_asset_extract (effect_asset));
*
* ]|
*
* In that example, the advantages of having a #GESAsset are that you can know what effects
* you are working with and let your user know about the avalaible ones, you can add metadata
* to the #GESAsset through the #GESMetaContainer interface and you have a model for your
* custom effects. Note that #GESAsset management is making easier thanks to the #GESProject class.
*
* Each asset is represented by a pair of @extractable_type and @id (string). Actually the @extractable_type
* is the type that implements the #GESExtractable interface, that means that for example for a #GESUriClip,
* the type that implements the #GESExtractable interface is #GESClip.
* The identifier represents different things depending on the @extractable_type and you should check
* the documentation of each type to know what the ID of #GESAsset actually represents for that type. By default,
* we only have one #GESAsset per type, and the @id is the name of the type, but this behaviour is overriden
* to be more useful. For example, for GESTransitionClips, the ID is the vtype of the transition
* you will extract from it (ie crossfade, box-wipe-rc etc..) For #GESEffect the ID is the
* @bin-description property of the extracted objects (ie the gst-launch style description of the bin that
* will be used).
*
* Each and every #GESAsset is cached into GES, and you can query those with the #ges_list_assets function.
* Also the system will automatically register #GESAssets for #GESFormatters and #GESTransitionClips
* and standard effects (actually not implemented yet) and you can simply query those calling:
* |[
* GList *formatter_assets, *tmp;
*
* // List all the transitions
* formatter_assets = ges_list_assets (GES_TYPE_FORMATTER);
*
* // Print some infos about the formatter GESAsset
* for (tmp = formatter_assets; tmp; tmp = tmp->next) {
* g_print ("Name of the formatter: %s, file extension it produces: %s",
* ges_meta_container_get_string (GES_META_CONTAINER (tmp->data), GES_META_FORMATTER_NAME),
* ges_meta_container_get_string (GES_META_CONTAINER (tmp->data), GES_META_FORMATTER_EXTENSION));
* }
*
* g_list_free (transition_assets);
*
* ]|
*
* You can request the creation of #GESAssets using either #ges_asset_request_async or
* #ges_asset_request_async. All the #GESAssets are cached and thus any asset that has already
* been created can be requested again without overhead.
*/
#include "ges.h"
#include "ges-internal.h"
#include <gst/gst.h>
enum
{
PROP_0,
PROP_TYPE,
PROP_ID,
PROP_LAST
};
typedef enum
{
ASSET_NOT_INITIALIZED,
ASSET_INITIALIZING, ASSET_INITIALIZED_WITH_ERROR,
ASSET_PROXIED,
ASSET_INITIALIZED
} GESAssetState;
static GParamSpec *_properties[PROP_LAST];
struct _GESAssetPrivate
{
gchar *id;
GESAssetState state;
GType extractable_type;
/* When a asset is proxied, instanciating it will
* return the asset it points to */
char *proxied_asset_id;
/* The error that accured when a asset has been initialized with error */
GError *error;
};
/* Internal structure to help avoid full loading
* of one asset several times
*/
typedef struct
{
GList *results;
GESAsset *asset;
} GESAssetCacheEntry;
/* Also protect all the entries in the cache */
static GMutex asset_cache_lock;
/* We are mapping entries by types and ID, such as:
*
* {
* first_extractable_type_name1 :
* {
* "some ID": GESAssetCacheEntry,
* "some other ID": GESAssetCacheEntry 2
* },
* second_extractable_type_name :
* {
* "some ID": GESAssetCacheEntry,
* "some other ID": GESAssetCacheEntry 2
* }
* }
*
* (The first extractable type is the type of the class that implemented
* the GESExtractable interface ie: GESClip, GESTimeline,
* GESFomatter, etc... but not subclasses)
*
* This is in order to be able to have 2 Asset with the same ID but
* different extractable types.
**/
static GHashTable *type_entries_table = NULL;
#define LOCK_CACHE (g_mutex_lock (&asset_cache_lock))
#define UNLOCK_CACHE (g_mutex_unlock (&asset_cache_lock))
static gchar *
_check_and_update_parameters (GType * extractable_type, const gchar * id,
GError ** error)
{
gchar *real_id;
GType old_type = *extractable_type;
*extractable_type =
ges_extractable_get_real_extractable_type_for_id (*extractable_type, id);
if (*extractable_type == G_TYPE_NONE) {
GST_WARNING ("No way to create a Asset for ID: %s, type: %s", id,
g_type_name (old_type));
if (error && *error == NULL)
g_set_error (error, GES_ERROR, GES_ERROR_ASSET_WRONG_ID,
"Wrong ID, can not find any extractable_type");
return NULL;
}
real_id = ges_extractable_type_check_id (*extractable_type, id, error);
if (real_id == NULL) {
GST_WARNING ("Wrong ID %s, can not create asset", id);
g_free (real_id);
if (error && *error == NULL)
g_set_error (error, GES_ERROR, GES_ERROR_ASSET_WRONG_ID, "Wrong ID");
return NULL;
}
return real_id;
}
static gboolean
initable_init (GInitable * initable, GCancellable * cancellable,
GError ** error)
{
gboolean ret;
GESAsset *asset = GES_ASSET (initable);
ges_asset_cache_put (gst_object_ref (asset), NULL);
ret = ges_asset_cache_set_loaded (asset->priv->extractable_type,
asset->priv->id, NULL);
g_clear_error (error);
return ret;
}
static void
async_initable_init_async (GAsyncInitable * initable, gint io_priority,
GCancellable * cancellable, GAsyncReadyCallback callback,
gpointer user_data)
{
GTask *task;
GError *error = NULL;
GESAsset *asset = GES_ASSET (initable);
task = g_task_new (asset, cancellable, callback, user_data);
ges_asset_cache_put (g_object_ref (asset), task);
switch (GES_ASSET_GET_CLASS (asset)->start_loading (asset, &error)) {
case GES_ASSET_LOADING_ERROR:
{
if (error == NULL)
g_set_error (&error, GES_ERROR, GES_ERROR_ASSET_LOADING,
"Could not start loading asset");
/* FIXME Define error code */
ges_asset_cache_set_loaded (asset->priv->extractable_type,
asset->priv->id, error);
g_error_free (error);
return;
}
case GES_ASSET_LOADING_OK:
{
ges_asset_cache_set_loaded (asset->priv->extractable_type,
asset->priv->id, error);
return;
}
case GES_ASSET_LOADING_ASYNC:
/* If Async.... let it go */
break;
}
}
static void
async_initable_iface_init (GAsyncInitableIface * async_initable_iface)
{
async_initable_iface->init_async = async_initable_init_async;
}
static void
initable_iface_init (GInitableIface * initable_iface)
{
initable_iface->init = initable_init;
}
G_DEFINE_TYPE_WITH_CODE (GESAsset, ges_asset, G_TYPE_OBJECT,
G_IMPLEMENT_INTERFACE (G_TYPE_ASYNC_INITABLE, async_initable_iface_init)
G_IMPLEMENT_INTERFACE (G_TYPE_INITABLE, initable_iface_init)
G_IMPLEMENT_INTERFACE (GES_TYPE_META_CONTAINER, NULL));
/* GESAsset virtual methods default implementation */
static GESAssetLoadingReturn
ges_asset_start_loading_default (GESAsset * asset, GError ** error)
{
return GES_ASSET_LOADING_OK;
}
static GESExtractable *
ges_asset_extract_default (GESAsset * asset, GError ** error)
{
guint n_params;
GParameter *params;
GESAssetPrivate *priv = asset->priv;
GESExtractable *n_extractable;
params = ges_extractable_type_get_parameters_from_id (priv->extractable_type,
priv->id, &n_params);
n_extractable = g_object_newv (priv->extractable_type, n_params, params);
while (n_params--)
g_value_unset (&params[n_params].value);
if (params)
g_free (params);
return n_extractable;
}
static gboolean
ges_asset_request_id_update_default (GESAsset * self, gchar ** proposed_new_id,
GError * error)
{
return FALSE;
}
/* GObject virtual methods implementation */
static void
ges_asset_get_property (GObject * object, guint property_id,
GValue * value, GParamSpec * pspec)
{
GESAsset *asset = GES_ASSET (object);
switch (property_id) {
case PROP_TYPE:
g_value_set_gtype (value, asset->priv->extractable_type);
break;
case PROP_ID:
g_value_set_string (value, asset->priv->id);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
}
}
static void
ges_asset_set_property (GObject * object, guint property_id,
const GValue * value, GParamSpec * pspec)
{
GESAsset *asset = GES_ASSET (object);
switch (property_id) {
case PROP_TYPE:
asset->priv->extractable_type = g_value_get_gtype (value);
ges_extractable_register_metas (asset->priv->extractable_type, asset);
break;
case PROP_ID:
asset->priv->id = g_value_dup_string (value);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
}
}
static void
ges_asset_finalize (GObject * object)
{
GESAssetPrivate *priv = GES_ASSET (object)->priv;
if (priv->id)
g_free (priv->id);
if (priv->proxied_asset_id)
g_free (priv->proxied_asset_id);
if (priv->error)
g_error_free (priv->error);
G_OBJECT_CLASS (ges_asset_parent_class)->finalize (object);
}
void
ges_asset_class_init (GESAssetClass * klass)
{
GObjectClass *object_class = G_OBJECT_CLASS (klass);
g_type_class_add_private (klass, sizeof (GESAssetPrivate));
object_class->get_property = ges_asset_get_property;
object_class->set_property = ges_asset_set_property;
object_class->finalize = ges_asset_finalize;
_properties[PROP_TYPE] =
g_param_spec_gtype ("extractable-type", "Extractable type",
"The type of the Object that can be extracted out of the asset",
G_TYPE_OBJECT, G_PARAM_CONSTRUCT_ONLY | G_PARAM_READWRITE);
_properties[PROP_ID] =
g_param_spec_string ("id", "Identifier",
"The unic identifier of the asset", NULL,
G_PARAM_CONSTRUCT_ONLY | G_PARAM_READWRITE);
g_object_class_install_properties (object_class, PROP_LAST, _properties);
klass->start_loading = ges_asset_start_loading_default;
klass->extract = ges_asset_extract_default;
klass->request_id_update = ges_asset_request_id_update_default;
klass->inform_proxy = NULL;
}
void
ges_asset_init (GESAsset * self)
{
self->priv = G_TYPE_INSTANCE_GET_PRIVATE (self,
GES_TYPE_ASSET, GESAssetPrivate);
self->priv->state = ASSET_INITIALIZING;
self->priv->proxied_asset_id = NULL;
}
/* Internal methods */
/* Find the type that implemented the GESExtractable interface */
static inline const gchar *
_extractable_type_name (GType type)
{
while (1) {
if (g_type_is_a (g_type_parent (type), GES_TYPE_EXTRACTABLE))
type = g_type_parent (type);
else
return g_type_name (type);
}
}
static inline GESAssetCacheEntry *
_lookup_entry (GType extractable_type, const gchar * id)
{
GHashTable *entries_table;
entries_table = g_hash_table_lookup (type_entries_table,
_extractable_type_name (extractable_type));
if (entries_table)
return g_hash_table_lookup (entries_table, id);
return NULL;
}
static void
_free_entries (gpointer entry)
{
g_slice_free (GESAssetCacheEntry, entry);
}
static void
_gtask_return_true (GTask * task)
{
g_task_return_boolean (task, TRUE);
}
/**
* ges_asset_cache_lookup:
*
* @id String identifier of asset
*
* Looks for asset with specified id in cache and it's completely loaded.
*
* Returns: (transfer none): The #GESAsset found or %NULL
*/
GESAsset *
ges_asset_cache_lookup (GType extractable_type, const gchar * id)
{
GESAsset *asset = NULL;
GESAssetCacheEntry *entry = NULL;
g_return_val_if_fail (id, NULL);
LOCK_CACHE;
entry = _lookup_entry (extractable_type, id);
if (entry)
asset = entry->asset;
UNLOCK_CACHE;
return asset;
}
static void
ges_asset_cache_append_task (GType extractable_type,
const gchar * id, GTask * task)
{
GESAssetCacheEntry *entry = NULL;
LOCK_CACHE;
if ((entry = _lookup_entry (extractable_type, id)))
entry->results = g_list_append (entry->results, task);
UNLOCK_CACHE;
}
gboolean
ges_asset_cache_set_loaded (GType extractable_type, const gchar * id,
GError * error)
{
GList *tmp;
GESAsset *asset;
GESAssetCacheEntry *entry = NULL;
LOCK_CACHE;
if ((entry = _lookup_entry (extractable_type, id)) == NULL) {
UNLOCK_CACHE;
GST_ERROR ("Calling but type %s ID: %s not in cached, "
"something massively screwed", g_type_name (extractable_type), id);
return FALSE;
}
asset = entry->asset;
GST_DEBUG_OBJECT (entry->asset, ": (extractable type: %s) loaded, calling %i "
"callback (Error: %s)", g_type_name (asset->priv->extractable_type),
g_list_length (entry->results), error ? error->message : "");
if (error) {
GList *results = entry->results;
asset->priv->state = ASSET_INITIALIZED_WITH_ERROR;
if (asset->priv->error)
g_error_free (asset->priv->error);
asset->priv->error = g_error_copy (error);
entry->results = NULL;
UNLOCK_CACHE;
/* In case of error we do not want to emit in idle as we need to recover
* if possible */
for (tmp = results; tmp; tmp = tmp->next) {
g_task_return_error (tmp->data, g_error_copy (error));
gst_object_unref (tmp->data);
}
g_list_free (results);
return TRUE;
} else {
GList *results;
asset->priv->state = ASSET_INITIALIZED;
results = entry->results;
entry->results = NULL;
UNLOCK_CACHE;
g_list_foreach (results, (GFunc) _gtask_return_true, NULL);
g_list_free_full (results, gst_object_unref);
}
return TRUE;
}
void
ges_asset_cache_put (GESAsset * asset, GTask * task)
{
GType extractable_type;
const gchar *asset_id;
GESAssetCacheEntry *entry;
/* Needing to work with the cache, taking the lock */
asset_id = ges_asset_get_id (asset);
extractable_type = asset->priv->extractable_type;
LOCK_CACHE;
if (!(entry = _lookup_entry (extractable_type, asset_id))) {
GHashTable *entries_table;
entries_table = g_hash_table_lookup (type_entries_table,
_extractable_type_name (extractable_type));
if (entries_table == NULL) {
entries_table = g_hash_table_new_full (g_str_hash, g_str_equal, g_free,
_free_entries);
g_hash_table_insert (type_entries_table,
g_strdup (_extractable_type_name (extractable_type)), entries_table);
}
entry = g_slice_new0 (GESAssetCacheEntry);
entry->asset = asset;
if (task)
entry->results = g_list_prepend (entry->results, task);
g_hash_table_insert (entries_table, (gpointer) g_strdup (asset_id),
(gpointer) entry);
} else {
if (task) {
GST_DEBUG ("%s already in cache, adding result %p", asset_id, task);
entry->results = g_list_prepend (entry->results, task);
}
}
UNLOCK_CACHE;
}
void
ges_asset_cache_init (void)
{
g_mutex_init (&asset_cache_lock);
type_entries_table = g_hash_table_new_full (g_str_hash, g_str_equal,
NULL, (GDestroyNotify) g_hash_table_unref);
_init_formatter_assets ();
_init_standard_transition_assets ();
}
gboolean
ges_asset_request_id_update (GESAsset * asset, gchar ** proposed_id,
GError * error)
{
return GES_ASSET_GET_CLASS (asset)->request_id_update (asset, proposed_id,
error);
}
gboolean
ges_asset_set_proxy (GESAsset * asset, const gchar * new_id)
{
GESAssetClass *class;
if (g_strcmp0 (asset->priv->id, new_id) == 0) {
GST_WARNING_OBJECT (asset, "Trying to proxy to itself (%s),"
" NOT possible", new_id);
return FALSE;
} else if (g_strcmp0 (asset->priv->proxied_asset_id, new_id) == 0) {
GST_WARNING_OBJECT (asset,
"Trying to proxy to same currently set proxy: %s -- %s",
asset->priv->proxied_asset_id, new_id);
return FALSE;
}
if (asset->priv->proxied_asset_id)
g_free (asset->priv->proxied_asset_id);
asset->priv->state = ASSET_PROXIED;
asset->priv->proxied_asset_id = g_strdup (new_id);
class = GES_ASSET_GET_CLASS (asset);
if (class->inform_proxy)
GES_ASSET_GET_CLASS (asset)->inform_proxy (asset, new_id);
GST_DEBUG_OBJECT (asset, "Now proxied to %s", new_id);
return TRUE;
}
/* Caution, this method should be used in rare cases (ie: for the project
* as we can change its ID from a useless one to a proper URI). In most
* cases you want to update the ID creating a proxy
*/
void
ges_asset_set_id (GESAsset * asset, const gchar * id)
{
GHashTable *entries;
gpointer orig_id = NULL;
GESAssetCacheEntry *entry = NULL;
GESAssetPrivate *priv = asset->priv;
if (priv->state != ASSET_INITIALIZED) {
GST_WARNING_OBJECT (asset, "Trying to rest ID on an object that is"
" not properly loaded");
return;
}
if (g_strcmp0 (id, priv->id) == 0) {
GST_DEBUG_OBJECT (asset, "ID is already %s", id);
return;
}
LOCK_CACHE;
entries = g_hash_table_lookup (type_entries_table,
_extractable_type_name (asset->priv->extractable_type));
g_return_if_fail (g_hash_table_lookup_extended (entries, priv->id, &orig_id,
(gpointer *) & entry));
g_hash_table_steal (entries, priv->id);
g_hash_table_insert (entries, g_strdup (id), entry);
GST_DEBUG_OBJECT (asset, "Changing id from %s to %s", priv->id, id);
g_free (priv->id);
g_free (orig_id);
priv->id = g_strdup (id);
UNLOCK_CACHE;
}
static GESAsset *
_unsure_material_for_wrong_id (const gchar * wrong_id, GType extractable_type,
GError * error)
{
GESAsset *asset;
if ((asset = ges_asset_cache_lookup (extractable_type, wrong_id)))
return asset;
/* It is a dummy GESAsset, we just bruteforce its creation */
asset = g_object_new (GES_TYPE_ASSET, "id", wrong_id,
"extractable-type", extractable_type, NULL);
ges_asset_cache_put (asset, NULL);
ges_asset_cache_set_loaded (extractable_type, wrong_id, error);
return asset;
}
/**********************************
* *
* API implementation *
* *
**********************************/
/**
* ges_asset_get_extractable_type:
* @self: The #GESAsset
*
* Gets the type of object that can be extracted from @self
*
* Returns: the type of object that can be extracted from @self
*/
GType
ges_asset_get_extractable_type (GESAsset * self)
{
return self->priv->extractable_type;
}
/**
* ges_asset_request:
* @extractable_type: The #GType of the object that can be extracted from the new asset.
* @id: (allow-none): The Identifier or %NULL
* @error: (allow-none): An error to be set in case something wrong happens or %NULL
*
* Create a #GESAsset in the most simple cases, you should look at the @extractable_type
* documentation to see if that constructor can be called for this particular type
*
* As it is recommanded not to instanciate assets for GESUriClip synchronously,
* it will not work with this method, but you can instead use the specific
* #ges_uri_clip_asset_request_sync method if you really want to.
*
* Returns: (transfer full) (allow-none): A reference to the wanted #GESAsset or %NULL
*/
GESAsset *
ges_asset_request (GType extractable_type, const gchar * id, GError ** error)
{
gchar *real_id;
GError *lerr = NULL;
GESAsset *asset = NULL;
g_return_val_if_fail (error == NULL || *error == NULL, NULL);
g_return_val_if_fail (g_type_is_a (extractable_type, G_TYPE_OBJECT), NULL);
g_return_val_if_fail (g_type_is_a (extractable_type, GES_TYPE_EXTRACTABLE),
NULL);
real_id = _check_and_update_parameters (&extractable_type, id, &lerr);
if (real_id == NULL) {
/* We create an asset for that wrong ID so we have a reference that the
* user requested it */
_unsure_material_for_wrong_id (id, extractable_type, lerr);
real_id = g_strdup (id);
}
asset = ges_asset_cache_lookup (extractable_type, real_id);
if (asset) {
while (TRUE) {
switch (asset->priv->state) {
case ASSET_INITIALIZED:
gst_object_ref (asset);
goto done;
case ASSET_INITIALIZING:
asset = NULL;
goto done;
case ASSET_PROXIED:
asset =
ges_asset_cache_lookup (asset->priv->extractable_type,
asset->priv->proxied_asset_id);
if (asset == NULL) {
GST_ERROR ("Asset against a asset we do not"
" have in cache, something massively screwed");
goto done;
}
break;
case ASSET_INITIALIZED_WITH_ERROR:
GST_WARNING_OBJECT (asset, "Initialized with error, not returning");
if (error)
*error = g_error_copy (asset->priv->error);
asset = NULL;
goto done;
default:
GST_WARNING ("Case %i not handle, returning", asset->priv->state);
goto done;
}
}
} else {
GObjectClass *klass;
GInitableIface *iface;
GType asset_type = ges_extractable_type_get_asset_type (extractable_type);
klass = g_type_class_ref (asset_type);
iface = g_type_interface_peek (klass, G_TYPE_INITABLE);
if (iface->init) {
asset = g_initable_new (asset_type,
NULL, NULL, "id", real_id, "extractable-type",
extractable_type, NULL);
} else {
GST_WARNING ("Tried to create an Asset for type %s but no ->init method",
g_type_name (extractable_type));
}
g_type_class_unref (klass);
}
done:
if (real_id)
g_free (real_id);
GST_DEBUG ("New asset created synchronously: %p", asset);
return asset;
}
/**
* ges_asset_request_async:
* @extractable_type: The #GType of the object that can be extracted from the
* new asset. The class must implement the #GESExtractable interface.
* @id: The Identifier of the asset we want to create. This identifier depends of the extractable,
* type you want. By default it is the name of the class itself (or %NULL), but for example for a
* GESEffect, it will be the pipeline description, for a GESUriClip it
* will be the name of the file, etc... You should refer to the documentation of the #GESExtractable
* type you want to create a #GESAsset for.
* @cancellable: (allow-none): optional %GCancellable object, %NULL to ignore.
* @callback: a #GAsyncReadyCallback to call when the initialization is finished,
* Note that the @source of the callback will be the #GESAsset, but you need to
* make sure that the asset is properly loaded using the #ges_asset_request_finish
* method. This asset can not be used as is.
* @user_data: The user data to pass when @callback is called
*
* Request a new #GESAsset asyncronously, @callback will be called when the materail is
* ready to be used or if an error occured.
*
* Example of request of a GESAsset async:
* |[
* // The request callback
* static void
* asset_loaded_cb (GESAsset * source, GAsyncResult * res, gpointer user_data)
* {
* GESAsset *asset;
* GError *error = NULL;
*
* asset = ges_asset_request_finish (res, &error);
* if (asset) {
* g_print ("The file: %s is usable as a FileSource",
* ges_asset_get_id (asset));
* } else {
* g_print ("The file: %s is *not* usable as a FileSource because: %s",
* ges_asset_get_id (source), error->message);
* }
*
* gst_object_unref (mfs);
* }
*
* // The request:
* ges_asset_request_async (GES_TYPE_URI_CLIP, some_uri, NULL,
* (GAsyncReadyCallback) asset_loaded_cb, user_data);
* ]|
*/
void
ges_asset_request_async (GType extractable_type,
const gchar * id, GCancellable * cancellable, GAsyncReadyCallback callback,
gpointer user_data)
{
gchar *real_id;
GESAsset *asset;
GError *error = NULL;
g_return_if_fail (g_type_is_a (extractable_type, G_TYPE_OBJECT));
g_return_if_fail (g_type_is_a (extractable_type, GES_TYPE_EXTRACTABLE));
g_return_if_fail (callback);
GST_DEBUG ("Creating asset with extractable type %s and ID=%s",
g_type_name (extractable_type), id);
real_id = _check_and_update_parameters (&extractable_type, id, &error);
if (error) {
_unsure_material_for_wrong_id (id, extractable_type, error);
real_id = g_strdup (id);
}
/* Check if we already have a asset for this ID */
asset = ges_asset_cache_lookup (extractable_type, real_id);
if (asset) {
GTask *task = g_task_new (asset, NULL, callback, user_data);
/* In the case of proxied asset, we will loop until we find the
* last asset of the chain of proxied asset */
while (TRUE) {
switch (asset->priv->state) {
case ASSET_INITIALIZED:
gst_object_ref (asset);
GST_DEBUG_OBJECT (asset, "Asset in cache and initialized, "
"using it");
/* Takes its own references to @asset */
g_task_return_boolean (task, TRUE);
goto done;
case ASSET_INITIALIZING:
GST_DEBUG_OBJECT (asset, "Asset in cache and but not "
"initialized, setting a new callback");
ges_asset_cache_append_task (extractable_type, real_id, task);
goto done;
case ASSET_PROXIED:
asset =
ges_asset_cache_lookup (asset->priv->extractable_type,
asset->priv->proxied_asset_id);
if (asset == NULL) {
GST_ERROR ("Asset proxied against a asset we do not"
" have in cache, something massively screwed");
goto done;
}
break;
case ASSET_INITIALIZED_WITH_ERROR:
g_task_return_error (task,
error ? error : g_error_copy (asset->priv->error));
goto done;
default:
GST_WARNING ("Case %i not handle, returning", asset->priv->state);
return;
}
}
}
g_async_initable_new_async (ges_extractable_type_get_asset_type
(extractable_type), G_PRIORITY_DEFAULT, cancellable, callback, user_data,
"id", real_id, "extractable-type", extractable_type, NULL);
done:
if (real_id)
g_free (real_id);
}
/**
* ges_asset_get_id:
* @self: The #GESAsset to get ID from
*
* Gets the ID of a #GESAsset
*
* Returns: The ID of @self
*/
const gchar *
ges_asset_get_id (GESAsset * self)
{
g_return_val_if_fail (GES_IS_ASSET (self), NULL);
return self->priv->id;
}
/**
* ges_asset_extract:
* @self: The #GESAsset to get extract an object from
* @error: (allow-none): An error to be set in case something wrong happens or %NULL
*
* Extracts a new #GObject from @asset. The type of the object is
* defined by the extractable-type of @asset, you can check what
* type will be extracted from @asset using
* #ges_asset_get_extractable_type
*
* Returns: (transfer floating) (allow-none): A newly created #GESExtractable
*/
GESExtractable *
ges_asset_extract (GESAsset * self, GError ** error)
{
GESExtractable *extractable;
g_return_val_if_fail (GES_IS_ASSET (self), NULL);
g_return_val_if_fail (GES_ASSET_GET_CLASS (self)->extract, NULL);
GST_DEBUG_OBJECT (self, "Extracting asset of type %s",
g_type_name (self->priv->extractable_type));
extractable = GES_ASSET_GET_CLASS (self)->extract (self, error);
if (extractable == NULL)
return NULL;
if (ges_extractable_get_asset (extractable) == NULL)
ges_extractable_set_asset (extractable, self);
return extractable;
}
/**
* ges_asset_request_finish:
* @res: The #GAsyncResult from which to get the newly created #GESAsset
* @error: (out) (allow-none) (transfer full): An error to be set in case
* something wrong happens or %NULL
*
* Finalize the request of an async #GESAsset
*
* Returns: (transfer full)(allow-none): The #GESAsset previously requested
*/
GESAsset *
ges_asset_request_finish (GAsyncResult * res, GError ** error)
{
GObject *object;
GObject *source_object;
g_return_val_if_fail (G_IS_ASYNC_RESULT (res), NULL);
source_object = g_async_result_get_source_object (res);
g_assert (source_object != NULL);
object = g_async_initable_new_finish (G_ASYNC_INITABLE (source_object),
res, error);
gst_object_unref (source_object);
return GES_ASSET (object);
}
/**
* ges_list_assets:
* @filter: Type of assets to list, #GES_TYPE_EXTRACTABLE will list
* all assets
*
* List all @asset filtering per filter as defined by @filter.
* It copies the asset and thus will not be updated in time.
*
* Returns: (transfer container) (element-type GESAsset): The list of
* #GESAsset the object contains
*/
GList *
ges_list_assets (GType filter)
{
GList *ret = NULL;
GESAsset *asset;
GHashTableIter iter, types_iter;
gpointer key, value, typename, assets;
g_return_val_if_fail (g_type_is_a (filter, GES_TYPE_EXTRACTABLE), NULL);
LOCK_CACHE;
g_hash_table_iter_init (&types_iter, type_entries_table);
while (g_hash_table_iter_next (&types_iter, &typename, &assets)) {
if (g_type_is_a (filter, g_type_from_name ((gchar *) typename)) == FALSE)
continue;
g_hash_table_iter_init (&iter, (GHashTable *) assets);
while (g_hash_table_iter_next (&iter, &key, &value)) {
asset = ((GESAssetCacheEntry *) value)->asset;
if (g_type_is_a (asset->priv->extractable_type, filter))
ret = g_list_append (ret, asset);
}
}
UNLOCK_CACHE;
return ret;
}