--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/gstreamer_core/gst/gsttaglist.c Thu Dec 17 08:53:32 2009 +0200
@@ -0,0 +1,1555 @@
+/* GStreamer
+ * Copyright (C) 2003 Benjamin Otte <in7y118@public.uni-hamburg.de>
+ *
+ * gsttaglist.c: tag support (aka metadata)
+ *
+ * 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:gsttaglist
+ * @short_description: List of tags and values used to describe media metadata
+ *
+ * List of tags and values used to describe media metadata.
+ *
+ * Last reviewed on 2005-11-23 (0.9.5)
+ */
+
+#ifdef HAVE_CONFIG_H
+# include "config.h"
+#endif
+
+#include "gst_private.h"
+#include "gst-i18n-lib.h"
+#include "gsttaglist.h"
+#include "gstinfo.h"
+#include "gstvalue.h"
+#include "gstbuffer.h"
+
+#include <gobject/gvaluecollector.h>
+#include <string.h>
+
+#ifdef __SYMBIAN32__
+#include <glib_global.h>
+#endif
+
+#define GST_TAG_IS_VALID(tag) (gst_tag_get_info (tag) != NULL)
+
+/* FIXME 0.11: use GParamSpecs or something similar for tag registrations,
+ * possibly even gst_tag_register(). Especially value ranges might be
+ * useful for some tags. */
+
+typedef struct
+{
+ GType type; /* type the data is in */
+
+ gchar *nick; /* translated name */
+ gchar *blurb; /* translated description of type */
+
+ GstTagMergeFunc merge_func; /* functions to merge the values */
+ GstTagFlag flag; /* type of tag */
+}
+GstTagInfo;
+
+#define TAGLIST "taglist"
+static GQuark gst_tag_list_quark;
+static GMutex *__tag_mutex;
+static GHashTable *__tags;
+
+#define TAG_LOCK g_mutex_lock (__tag_mutex)
+#define TAG_UNLOCK g_mutex_unlock (__tag_mutex)
+
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+GType
+gst_tag_list_get_type (void)
+{
+ static GType _gst_tag_list_type = 0;
+
+ if (G_UNLIKELY (_gst_tag_list_type == 0)) {
+ _gst_tag_list_type = g_boxed_type_register_static ("GstTagList",
+ (GBoxedCopyFunc) gst_tag_list_copy, (GBoxedFreeFunc) gst_tag_list_free);
+
+#if 0
+ g_value_register_transform_func (_gst_tag_list_type, G_TYPE_STRING,
+ _gst_structure_transform_to_string);
+#endif
+ }
+
+ return _gst_tag_list_type;
+}
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+
+
+void
+_gst_tag_initialize (void)
+{
+ gst_tag_list_quark = g_quark_from_static_string (TAGLIST);
+ __tag_mutex = g_mutex_new ();
+ __tags = g_hash_table_new (g_direct_hash, g_direct_equal);
+ gst_tag_register (GST_TAG_TITLE, GST_TAG_FLAG_META,
+ G_TYPE_STRING,
+ _("title"), _("commonly used title"), gst_tag_merge_strings_with_comma);
+ gst_tag_register (GST_TAG_TITLE_SORTNAME, GST_TAG_FLAG_META,
+ G_TYPE_STRING,
+ _("title sortname"), _("commonly used title for sorting purposes"), NULL);
+ gst_tag_register (GST_TAG_ARTIST, GST_TAG_FLAG_META,
+ G_TYPE_STRING,
+ _("artist"),
+ _("person(s) responsible for the recording"),
+ gst_tag_merge_strings_with_comma);
+ gst_tag_register (GST_TAG_ARTIST_SORTNAME, GST_TAG_FLAG_META,
+ G_TYPE_STRING,
+ _("artist sortname"),
+ _("person(s) responsible for the recording for sorting purposes"), NULL);
+ gst_tag_register (GST_TAG_ALBUM, GST_TAG_FLAG_META,
+ G_TYPE_STRING,
+ _("album"),
+ _("album containing this data"), gst_tag_merge_strings_with_comma);
+ gst_tag_register (GST_TAG_ALBUM_SORTNAME, GST_TAG_FLAG_META,
+ G_TYPE_STRING,
+ _("album sortname"),
+ _("album containing this data for sorting purposes"), NULL);
+ gst_tag_register (GST_TAG_DATE, GST_TAG_FLAG_META, GST_TYPE_DATE,
+ _("date"), _("date the data was created (as a GDate structure)"), NULL);
+ gst_tag_register (GST_TAG_GENRE, GST_TAG_FLAG_META,
+ G_TYPE_STRING,
+ _("genre"),
+ _("genre this data belongs to"), gst_tag_merge_strings_with_comma);
+ gst_tag_register (GST_TAG_COMMENT, GST_TAG_FLAG_META,
+ G_TYPE_STRING,
+ _("comment"),
+ _("free text commenting the data"), gst_tag_merge_use_first);
+ gst_tag_register (GST_TAG_EXTENDED_COMMENT, GST_TAG_FLAG_META,
+ G_TYPE_STRING,
+ _("extended comment"),
+ _("free text commenting the data in key=value or key[en]=comment form"),
+ gst_tag_merge_use_first);
+ gst_tag_register (GST_TAG_TRACK_NUMBER, GST_TAG_FLAG_META,
+ G_TYPE_UINT,
+ _("track number"),
+ _("track number inside a collection"), gst_tag_merge_use_first);
+ gst_tag_register (GST_TAG_TRACK_COUNT, GST_TAG_FLAG_META,
+ G_TYPE_UINT,
+ _("track count"),
+ _("count of tracks inside collection this track belongs to"),
+ gst_tag_merge_use_first);
+ gst_tag_register (GST_TAG_ALBUM_VOLUME_NUMBER, GST_TAG_FLAG_META,
+ G_TYPE_UINT,
+ _("disc number"),
+ _("disc number inside a collection"), gst_tag_merge_use_first);
+ gst_tag_register (GST_TAG_ALBUM_VOLUME_COUNT, GST_TAG_FLAG_META,
+ G_TYPE_UINT,
+ _("disc count"),
+ _("count of discs inside collection this disc belongs to"),
+ gst_tag_merge_use_first);
+ gst_tag_register (GST_TAG_LOCATION, GST_TAG_FLAG_META,
+ G_TYPE_STRING,
+ _("location"),
+ _("original location of file as a URI"),
+ gst_tag_merge_strings_with_comma);
+ gst_tag_register (GST_TAG_DESCRIPTION, GST_TAG_FLAG_META,
+ G_TYPE_STRING,
+ _("description"),
+ _("short text describing the content of the data"),
+ gst_tag_merge_strings_with_comma);
+ gst_tag_register (GST_TAG_VERSION, GST_TAG_FLAG_META,
+ G_TYPE_STRING, _("version"), _("version of this data"), NULL);
+ gst_tag_register (GST_TAG_ISRC, GST_TAG_FLAG_META,
+ G_TYPE_STRING,
+ _("ISRC"),
+ _
+ ("International Standard Recording Code - see http://www.ifpi.org/isrc/"),
+ NULL);
+ gst_tag_register (GST_TAG_ORGANIZATION, GST_TAG_FLAG_META, G_TYPE_STRING, _("organization"), _("organization"), /* FIXME */
+ gst_tag_merge_strings_with_comma);
+ gst_tag_register (GST_TAG_COPYRIGHT, GST_TAG_FLAG_META,
+ G_TYPE_STRING, _("copyright"), _("copyright notice of the data"), NULL);
+ gst_tag_register (GST_TAG_COPYRIGHT_URI, GST_TAG_FLAG_META,
+ G_TYPE_STRING, _("copyright uri"),
+ _("URI to the copyright notice of the data"), NULL);
+ gst_tag_register (GST_TAG_CONTACT, GST_TAG_FLAG_META,
+ G_TYPE_STRING,
+ _("contact"), _("contact information"), gst_tag_merge_strings_with_comma);
+ gst_tag_register (GST_TAG_LICENSE, GST_TAG_FLAG_META,
+ G_TYPE_STRING, _("license"), _("license of data"), NULL);
+ gst_tag_register (GST_TAG_LICENSE_URI, GST_TAG_FLAG_META,
+ G_TYPE_STRING, _("license uri"),
+ _("URI to the license of the data"), NULL);
+ gst_tag_register (GST_TAG_PERFORMER, GST_TAG_FLAG_META,
+ G_TYPE_STRING,
+ _("performer"),
+ _("person(s) performing"), gst_tag_merge_strings_with_comma);
+ gst_tag_register (GST_TAG_COMPOSER, GST_TAG_FLAG_META,
+ G_TYPE_STRING,
+ _("composer"),
+ _("person(s) who composed the recording"),
+ gst_tag_merge_strings_with_comma);
+ gst_tag_register (GST_TAG_DURATION, GST_TAG_FLAG_DECODED,
+ G_TYPE_UINT64,
+ _("duration"), _("length in GStreamer time units (nanoseconds)"), NULL);
+ gst_tag_register (GST_TAG_CODEC, GST_TAG_FLAG_ENCODED,
+ G_TYPE_STRING,
+ _("codec"),
+ _("codec the data is stored in"), gst_tag_merge_strings_with_comma);
+ gst_tag_register (GST_TAG_VIDEO_CODEC, GST_TAG_FLAG_ENCODED,
+ G_TYPE_STRING,
+ _("video codec"), _("codec the video data is stored in"), NULL);
+ gst_tag_register (GST_TAG_AUDIO_CODEC, GST_TAG_FLAG_ENCODED,
+ G_TYPE_STRING,
+ _("audio codec"), _("codec the audio data is stored in"), NULL);
+ gst_tag_register (GST_TAG_BITRATE, GST_TAG_FLAG_ENCODED,
+ G_TYPE_UINT, _("bitrate"), _("exact or average bitrate in bits/s"), NULL);
+ gst_tag_register (GST_TAG_NOMINAL_BITRATE, GST_TAG_FLAG_ENCODED,
+ G_TYPE_UINT, _("nominal bitrate"), _("nominal bitrate in bits/s"), NULL);
+ gst_tag_register (GST_TAG_MINIMUM_BITRATE, GST_TAG_FLAG_ENCODED,
+ G_TYPE_UINT, _("minimum bitrate"), _("minimum bitrate in bits/s"), NULL);
+ gst_tag_register (GST_TAG_MAXIMUM_BITRATE, GST_TAG_FLAG_ENCODED,
+ G_TYPE_UINT, _("maximum bitrate"), _("maximum bitrate in bits/s"), NULL);
+ gst_tag_register (GST_TAG_ENCODER, GST_TAG_FLAG_ENCODED,
+ G_TYPE_STRING,
+ _("encoder"), _("encoder used to encode this stream"), NULL);
+ gst_tag_register (GST_TAG_ENCODER_VERSION, GST_TAG_FLAG_ENCODED,
+ G_TYPE_UINT,
+ _("encoder version"),
+ _("version of the encoder used to encode this stream"), NULL);
+ gst_tag_register (GST_TAG_SERIAL, GST_TAG_FLAG_ENCODED,
+ G_TYPE_UINT, _("serial"), _("serial number of track"), NULL);
+ gst_tag_register (GST_TAG_TRACK_GAIN, GST_TAG_FLAG_META,
+ G_TYPE_DOUBLE, _("replaygain track gain"), _("track gain in db"), NULL);
+ gst_tag_register (GST_TAG_TRACK_PEAK, GST_TAG_FLAG_META,
+ G_TYPE_DOUBLE, _("replaygain track peak"), _("peak of the track"), NULL);
+ gst_tag_register (GST_TAG_ALBUM_GAIN, GST_TAG_FLAG_META,
+ G_TYPE_DOUBLE, _("replaygain album gain"), _("album gain in db"), NULL);
+ gst_tag_register (GST_TAG_ALBUM_PEAK, GST_TAG_FLAG_META,
+ G_TYPE_DOUBLE, _("replaygain album peak"), _("peak of the album"), NULL);
+ gst_tag_register (GST_TAG_REFERENCE_LEVEL, GST_TAG_FLAG_META,
+ G_TYPE_DOUBLE, _("replaygain reference level"),
+ _("reference level of track and album gain values"), NULL);
+ gst_tag_register (GST_TAG_LANGUAGE_CODE, GST_TAG_FLAG_META, G_TYPE_STRING,
+ _("language code"),
+ _("language code for this stream, conforming to ISO-639-1"), NULL);
+ gst_tag_register (GST_TAG_IMAGE, GST_TAG_FLAG_META, GST_TYPE_BUFFER,
+ _("image"), _("image related to this stream"), gst_tag_merge_use_first);
+ gst_tag_register (GST_TAG_PREVIEW_IMAGE, GST_TAG_FLAG_META, GST_TYPE_BUFFER,
+ _("preview image"), _("preview image related to this stream"), NULL);
+ gst_tag_register (GST_TAG_BEATS_PER_MINUTE, GST_TAG_FLAG_META, G_TYPE_DOUBLE,
+ _("beats per minute"), _("number of beats per minute in audio"), NULL);
+
+}
+
+/**
+ * gst_tag_merge_use_first:
+ * @dest: uninitialized GValue to store result in
+ * @src: GValue to copy from
+ *
+ * This is a convenience function for the func argument of gst_tag_register().
+ * It creates a copy of the first value from the list.
+ */
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+
+void
+gst_tag_merge_use_first (GValue * dest, const GValue * src)
+{
+ const GValue *ret = gst_value_list_get_value (src, 0);
+
+ g_value_init (dest, G_VALUE_TYPE (ret));
+ g_value_copy (ret, dest);
+}
+
+/**
+ * gst_tag_merge_strings_with_comma:
+ * @dest: uninitialized GValue to store result in
+ * @src: GValue to copy from
+ *
+ * This is a convenience function for the func argument of gst_tag_register().
+ * It concatenates all given strings using a comma. The tag must be registered
+ * as a G_TYPE_STRING or this function will fail.
+ */
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+
+void
+gst_tag_merge_strings_with_comma (GValue * dest, const GValue * src)
+{
+ GString *str;
+ gint i, count;
+
+ count = gst_value_list_get_size (src);
+ str = g_string_new (g_value_get_string (gst_value_list_get_value (src, 0)));
+ for (i = 1; i < count; i++) {
+ /* seperator between two string */
+ str = g_string_append (str, _(", "));
+ str =
+ g_string_append (str, g_value_get_string (gst_value_list_get_value (src,
+ 1)));
+ }
+
+ g_value_init (dest, G_TYPE_STRING);
+ g_value_set_string_take_ownership (dest, str->str);
+ g_string_free (str, FALSE);
+}
+static GstTagInfo *
+gst_tag_lookup (GQuark entry)
+{
+ GstTagInfo *ret;
+
+ TAG_LOCK;
+ ret = g_hash_table_lookup (__tags, GUINT_TO_POINTER (entry));
+ TAG_UNLOCK;
+
+ return ret;
+}
+
+/**
+ * gst_tag_register:
+ * @name: the name or identifier string
+ * @flag: a flag describing the type of tag info
+ * @type: the type this data is in
+ * @nick: human-readable name
+ * @blurb: a human-readable description about this tag
+ * @func: function for merging multiple values of this tag, or NULL
+ *
+ * Registers a new tag type for the use with GStreamer's type system. If a type
+ * with that name is already registered, that one is used.
+ * The old registration may have used a different type however. So don't rely
+ * on your supplied values.
+ *
+ * Important: if you do not supply a merge function the implication will be
+ * that there can only be one single value for this tag in a tag list and
+ * any additional values will silenty be discarded when being added (unless
+ * #GST_TAG_MERGE_REPLACE, #GST_TAG_MERGE_REPLACE_ALL, or
+ * #GST_TAG_MERGE_PREPEND is used as merge mode, in which case the new
+ * value will replace the old one in the list).
+ *
+ * The merge function will be called from gst_tag_list_copy_value() when
+ * it is required that one or more values for a tag be condensed into
+ * one single value. This may happen from gst_tag_list_get_string(),
+ * gst_tag_list_get_int(), gst_tag_list_get_double() etc. What will happen
+ * exactly in that case depends on how the tag was registered and if a
+ * merge function was supplied and if so which one.
+ *
+ * Two default merge functions are provided: gst_tag_merge_use_first() and
+ * gst_tag_merge_strings_with_commas().
+ */
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+
+void
+gst_tag_register (const gchar * name, GstTagFlag flag, GType type,
+ const gchar * nick, const gchar * blurb, GstTagMergeFunc func)
+{
+ GQuark key;
+ GstTagInfo *info;
+
+ g_return_if_fail (name != NULL);
+ g_return_if_fail (nick != NULL);
+ g_return_if_fail (blurb != NULL);
+ g_return_if_fail (type != 0 && type != GST_TYPE_LIST);
+
+ key = g_quark_from_string (name);
+ info = gst_tag_lookup (key);
+
+ if (info) {
+ g_return_if_fail (info->type == type);
+ return;
+ }
+
+ info = g_new (GstTagInfo, 1);
+ info->flag = flag;
+ info->type = type;
+ info->nick = g_strdup (nick);
+ info->blurb = g_strdup (blurb);
+ info->merge_func = func;
+
+ TAG_LOCK;
+ g_hash_table_insert (__tags, GUINT_TO_POINTER (key), info);
+ TAG_UNLOCK;
+}
+
+/**
+ * gst_tag_exists:
+ * @tag: name of the tag
+ *
+ * Checks if the given type is already registered.
+ *
+ * Returns: TRUE if the type is already registered
+ */
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+
+gboolean
+gst_tag_exists (const gchar * tag)
+{
+ g_return_val_if_fail (tag != NULL, FALSE);
+
+ return gst_tag_lookup (g_quark_from_string (tag)) != NULL;
+}
+
+/**
+ * gst_tag_get_type:
+ * @tag: the tag
+ *
+ * Gets the #GType used for this tag.
+ *
+ * Returns: the #GType of this tag
+ */
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+
+GType
+gst_tag_get_type (const gchar * tag)
+{
+ GstTagInfo *info;
+
+ g_return_val_if_fail (tag != NULL, 0);
+ info = gst_tag_lookup (g_quark_from_string (tag));
+ g_return_val_if_fail (info != NULL, 0);
+
+ return info->type;
+}
+
+/**
+ * gst_tag_get_nick
+ * @tag: the tag
+ *
+ * Returns the human-readable name of this tag, You must not change or free
+ * this string.
+ *
+ * Returns: the human-readable name of this tag
+ */
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+
+const gchar *
+gst_tag_get_nick (const gchar * tag)
+{
+ GstTagInfo *info;
+
+ g_return_val_if_fail (tag != NULL, NULL);
+ info = gst_tag_lookup (g_quark_from_string (tag));
+ g_return_val_if_fail (info != NULL, NULL);
+
+ return info->nick;
+}
+
+/**
+ * gst_tag_get_description:
+ * @tag: the tag
+ *
+ * Returns the human-readable description of this tag, You must not change or
+ * free this string.
+ *
+ * Returns: the human-readable description of this tag
+ */
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+
+const gchar *
+gst_tag_get_description (const gchar * tag)
+{
+ GstTagInfo *info;
+
+ g_return_val_if_fail (tag != NULL, NULL);
+ info = gst_tag_lookup (g_quark_from_string (tag));
+ g_return_val_if_fail (info != NULL, NULL);
+
+ return info->blurb;
+}
+
+/**
+ * gst_tag_get_flag:
+ * @tag: the tag
+ *
+ * Gets the flag of @tag.
+ *
+ * Returns: the flag of this tag.
+ */
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+
+GstTagFlag
+gst_tag_get_flag (const gchar * tag)
+{
+ GstTagInfo *info;
+
+ g_return_val_if_fail (tag != NULL, GST_TAG_FLAG_UNDEFINED);
+ info = gst_tag_lookup (g_quark_from_string (tag));
+ g_return_val_if_fail (info != NULL, GST_TAG_FLAG_UNDEFINED);
+
+ return info->flag;
+}
+
+/**
+ * gst_tag_is_fixed:
+ * @tag: tag to check
+ *
+ * Checks if the given tag is fixed. A fixed tag can only contain one value.
+ * Unfixed tags can contain lists of values.
+ *
+ * Returns: TRUE, if the given tag is fixed.
+ */
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+
+gboolean
+gst_tag_is_fixed (const gchar * tag)
+{
+ GstTagInfo *info;
+
+ g_return_val_if_fail (tag != NULL, FALSE);
+ info = gst_tag_lookup (g_quark_from_string (tag));
+ g_return_val_if_fail (info != NULL, FALSE);
+
+ return info->merge_func == NULL;
+}
+
+/**
+ * gst_tag_list_new:
+ *
+ * Creates a new empty GstTagList.
+ *
+ * Returns: An empty tag list
+ */
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+
+GstTagList *
+gst_tag_list_new (void)
+{
+ return GST_TAG_LIST (gst_structure_new (TAGLIST, NULL));
+}
+
+/**
+ * gst_tag_list_is_empty:
+ * @list: A #GstTagList.
+ *
+ * Checks if the given taglist is empty.
+ *
+ * Returns: TRUE if the taglist is empty, otherwise FALSE.
+ *
+ * Since: 0.10.11
+ */
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+
+gboolean
+gst_tag_list_is_empty (const GstTagList * list)
+{
+ g_return_val_if_fail (list != NULL, FALSE);
+ g_return_val_if_fail (GST_IS_TAG_LIST (list), FALSE);
+
+ return (gst_structure_n_fields ((GstStructure *) list) == 0);
+}
+
+/**
+ * gst_is_tag_list:
+ * @p: Object that might be a taglist
+ *
+ * Checks if the given pointer is a taglist.
+ *
+ * Returns: TRUE, if the given pointer is a taglist
+ */
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+
+gboolean
+gst_is_tag_list (gconstpointer p)
+{
+ GstStructure *s = (GstStructure *) p;
+
+ g_return_val_if_fail (p != NULL, FALSE);
+
+ return (GST_IS_STRUCTURE (s) && s->name == gst_tag_list_quark);
+}
+typedef struct
+{
+ GstStructure *list;
+ GstTagMergeMode mode;
+}
+GstTagCopyData;
+static void
+gst_tag_list_add_value_internal (GstStructure * list, GstTagMergeMode mode,
+ GQuark tag, const GValue * value)
+{
+ GstTagInfo *info = gst_tag_lookup (tag);
+ const GValue *value2;
+
+ g_assert (info != NULL);
+
+ if (info->merge_func
+ && (value2 = gst_structure_id_get_value (list, tag)) != NULL) {
+ GValue dest = { 0, };
+
+ switch (mode) {
+ case GST_TAG_MERGE_REPLACE_ALL:
+ case GST_TAG_MERGE_REPLACE:
+ gst_structure_id_set_value (list, tag, value);
+ break;
+ case GST_TAG_MERGE_PREPEND:
+ gst_value_list_concat (&dest, value, value2);
+ gst_structure_id_set_value (list, tag, &dest);
+ g_value_unset (&dest);
+ break;
+ case GST_TAG_MERGE_APPEND:
+ gst_value_list_concat (&dest, value2, value);
+ gst_structure_id_set_value (list, tag, &dest);
+ g_value_unset (&dest);
+ break;
+ case GST_TAG_MERGE_KEEP:
+ case GST_TAG_MERGE_KEEP_ALL:
+ break;
+ default:
+ g_assert_not_reached ();
+ break;
+ }
+ } else {
+ switch (mode) {
+ case GST_TAG_MERGE_APPEND:
+ case GST_TAG_MERGE_KEEP:
+ if (gst_structure_id_get_value (list, tag) != NULL)
+ break;
+ /* fall through */
+ case GST_TAG_MERGE_REPLACE_ALL:
+ case GST_TAG_MERGE_REPLACE:
+ case GST_TAG_MERGE_PREPEND:
+ gst_structure_id_set_value (list, tag, value);
+ break;
+ case GST_TAG_MERGE_KEEP_ALL:
+ break;
+ default:
+ g_assert_not_reached ();
+ break;
+ }
+ }
+}
+static gboolean
+gst_tag_list_copy_foreach (GQuark tag, const GValue * value, gpointer user_data)
+{
+ GstTagCopyData *copy = (GstTagCopyData *) user_data;
+
+ gst_tag_list_add_value_internal (copy->list, copy->mode, tag, value);
+
+ return TRUE;
+}
+
+/**
+ * gst_tag_list_insert:
+ * @into: list to merge into
+ * @from: list to merge from
+ * @mode: the mode to use
+ *
+ * Inserts the tags of the second list into the first list using the given mode.
+ */
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+
+void
+gst_tag_list_insert (GstTagList * into, const GstTagList * from,
+ GstTagMergeMode mode)
+{
+ GstTagCopyData data;
+
+ g_return_if_fail (GST_IS_TAG_LIST (into));
+ g_return_if_fail (GST_IS_TAG_LIST (from));
+ g_return_if_fail (GST_TAG_MODE_IS_VALID (mode));
+
+ data.list = (GstStructure *) into;
+ data.mode = mode;
+ if (mode == GST_TAG_MERGE_REPLACE_ALL) {
+ gst_structure_remove_all_fields (data.list);
+ }
+ gst_structure_foreach ((GstStructure *) from, gst_tag_list_copy_foreach,
+ &data);
+}
+
+/**
+ * gst_tag_list_copy:
+ * @list: list to copy
+ *
+ * Copies a given #GstTagList.
+ *
+ * Returns: copy of the given list
+ */
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+
+GstTagList *
+gst_tag_list_copy (const GstTagList * list)
+{
+ g_return_val_if_fail (GST_IS_TAG_LIST (list), NULL);
+
+ return GST_TAG_LIST (gst_structure_copy ((GstStructure *) list));
+}
+
+/**
+ * gst_tag_list_merge:
+ * @list1: first list to merge
+ * @list2: second list to merge
+ * @mode: the mode to use
+ *
+ * Merges the two given lists into a new list. If one of the lists is NULL, a
+ * copy of the other is returned. If both lists are NULL, NULL is returned.
+ *
+ * Returns: the new list
+ */
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+
+GstTagList *
+gst_tag_list_merge (const GstTagList * list1, const GstTagList * list2,
+ GstTagMergeMode mode)
+{
+ g_return_val_if_fail (list1 == NULL || GST_IS_TAG_LIST (list1), NULL);
+ g_return_val_if_fail (list2 == NULL || GST_IS_TAG_LIST (list2), NULL);
+ g_return_val_if_fail (GST_TAG_MODE_IS_VALID (mode), NULL);
+
+ if (!list1 && !list2) {
+ return NULL;
+ } else if (!list1) {
+ return gst_tag_list_copy (list2);
+ } else if (!list2) {
+ return gst_tag_list_copy (list1);
+ } else {
+ GstTagList *ret;
+
+ ret = gst_tag_list_copy (list1);
+ gst_tag_list_insert (ret, list2, mode);
+ return ret;
+ }
+}
+
+/**
+ * gst_tag_list_free:
+ * @list: the list to free
+ *
+ * Frees the given list and all associated values.
+ */
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+
+void
+gst_tag_list_free (GstTagList * list)
+{
+ g_return_if_fail (GST_IS_TAG_LIST (list));
+ gst_structure_free ((GstStructure *) list);
+}
+
+/**
+ * gst_tag_list_get_tag_size:
+ * @list: a taglist
+ * @tag: the tag to query
+ *
+ * Checks how many value are stored in this tag list for the given tag.
+ *
+ * Returns: The number of tags stored
+ */
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+
+guint
+gst_tag_list_get_tag_size (const GstTagList * list, const gchar * tag)
+{
+ const GValue *value;
+
+ g_return_val_if_fail (GST_IS_TAG_LIST (list), 0);
+
+ value = gst_structure_get_value ((GstStructure *) list, tag);
+ if (value == NULL)
+ return 0;
+ if (G_VALUE_TYPE (value) != GST_TYPE_LIST)
+ return 1;
+
+ return gst_value_list_get_size (value);
+}
+
+/**
+ * gst_tag_list_add:
+ * @list: list to set tags in
+ * @mode: the mode to use
+ * @tag: tag
+ * @...: NULL-terminated list of values to set
+ *
+ * Sets the values for the given tags using the specified mode.
+ */
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+
+void
+gst_tag_list_add (GstTagList * list, GstTagMergeMode mode, const gchar * tag,
+ ...)
+{
+ va_list args;
+
+ g_return_if_fail (GST_IS_TAG_LIST (list));
+ g_return_if_fail (GST_TAG_MODE_IS_VALID (mode));
+ g_return_if_fail (tag != NULL);
+
+ va_start (args, tag);
+ gst_tag_list_add_valist (list, mode, tag, args);
+ va_end (args);
+}
+
+/**
+ * gst_tag_list_add_values:
+ * @list: list to set tags in
+ * @mode: the mode to use
+ * @tag: tag
+ * @...: GValues to set
+ *
+ * Sets the GValues for the given tags using the specified mode.
+ */
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+
+void
+gst_tag_list_add_values (GstTagList * list, GstTagMergeMode mode,
+ const gchar * tag, ...)
+{
+ va_list args;
+
+ g_return_if_fail (GST_IS_TAG_LIST (list));
+ g_return_if_fail (GST_TAG_MODE_IS_VALID (mode));
+ g_return_if_fail (tag != NULL);
+
+ va_start (args, tag);
+ gst_tag_list_add_valist_values (list, mode, tag, args);
+ va_end (args);
+}
+
+/**
+ * gst_tag_list_add_valist:
+ * @list: list to set tags in
+ * @mode: the mode to use
+ * @tag: tag
+ * @var_args: tag / value pairs to set
+ *
+ * Sets the values for the given tags using the specified mode.
+ */
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+
+void
+gst_tag_list_add_valist (GstTagList * list, GstTagMergeMode mode,
+ const gchar * tag, va_list var_args)
+{
+ GstTagInfo *info;
+ GQuark quark;
+ gchar *error = NULL;
+
+ g_return_if_fail (GST_IS_TAG_LIST (list));
+ g_return_if_fail (GST_TAG_MODE_IS_VALID (mode));
+ g_return_if_fail (tag != NULL);
+
+ while (tag != NULL) {
+ GValue value = { 0, };
+
+ quark = g_quark_from_string (tag);
+ info = gst_tag_lookup (quark);
+ if (info == NULL)
+ g_warning ("no GstTag for %s", tag);
+ g_return_if_fail (info != NULL);
+ g_value_init (&value, info->type);
+ G_VALUE_COLLECT (&value, var_args, 0, &error);
+ if (error) {
+ g_warning ("%s: %s", G_STRLOC, error);
+ g_free (error);
+ /* we purposely leak the value here, it might not be
+ * in a sane state if an error condition occoured
+ */
+ return;
+ }
+ gst_tag_list_add_value_internal (list, mode, quark, &value);
+ g_value_unset (&value);
+ tag = va_arg (var_args, gchar *);
+ }
+}
+
+/**
+ * gst_tag_list_add_valist_values:
+ * @list: list to set tags in
+ * @mode: the mode to use
+ * @tag: tag
+ * @var_args: tag / GValue pairs to set
+ *
+ * Sets the GValues for the given tags using the specified mode.
+ */
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+
+void
+gst_tag_list_add_valist_values (GstTagList * list, GstTagMergeMode mode,
+ const gchar * tag, va_list var_args)
+{
+ GstTagInfo *info;
+ GQuark quark;
+
+ g_return_if_fail (GST_IS_TAG_LIST (list));
+ g_return_if_fail (GST_TAG_MODE_IS_VALID (mode));
+ g_return_if_fail (tag != NULL);
+
+ while (tag != NULL) {
+ quark = g_quark_from_string (tag);
+ info = gst_tag_lookup (quark);
+ g_return_if_fail (info != NULL);
+ gst_tag_list_add_value_internal (list, mode, quark, va_arg (var_args,
+ GValue *));
+ tag = va_arg (var_args, gchar *);
+ }
+}
+
+/**
+ * gst_tag_list_remove_tag:
+ * @list: list to remove tag from
+ * @tag: tag to remove
+ *
+ * Removes the given tag from the taglist.
+ */
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+
+void
+gst_tag_list_remove_tag (GstTagList * list, const gchar * tag)
+{
+ g_return_if_fail (GST_IS_TAG_LIST (list));
+ g_return_if_fail (tag != NULL);
+
+ gst_structure_remove_field ((GstStructure *) list, tag);
+}
+typedef struct
+{
+ GstTagForeachFunc func;
+ const GstTagList *tag_list;
+ gpointer data;
+}
+TagForeachData;
+static int
+structure_foreach_wrapper (GQuark field_id, const GValue * value,
+ gpointer user_data)
+{
+ TagForeachData *data = (TagForeachData *) user_data;
+
+ data->func (data->tag_list, g_quark_to_string (field_id), data->data);
+ return TRUE;
+}
+
+/**
+ * gst_tag_list_foreach:
+ * @list: list to iterate over
+ * @func: function to be called for each tag
+ * @user_data: user specified data
+ *
+ * Calls the given function for each tag inside the tag list. Note that if there
+ * is no tag, the function won't be called at all.
+ */
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+
+void
+gst_tag_list_foreach (const GstTagList * list, GstTagForeachFunc func,
+ gpointer user_data)
+{
+ TagForeachData data;
+
+ g_return_if_fail (GST_IS_TAG_LIST (list));
+ g_return_if_fail (func != NULL);
+
+ data.func = func;
+ data.tag_list = list;
+ data.data = user_data;
+ gst_structure_foreach ((GstStructure *) list, structure_foreach_wrapper,
+ &data);
+}
+
+/**
+ * gst_tag_list_get_value_index:
+ * @list: a #GstTagList
+ * @tag: tag to read out
+ * @index: number of entry to read out
+ *
+ * Gets the value that is at the given index for the given tag in the given
+ * list.
+ *
+ * Returns: The GValue for the specified entry or NULL if the tag wasn't
+ * available or the tag doesn't have as many entries
+ */
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+
+G_CONST_RETURN GValue *
+gst_tag_list_get_value_index (const GstTagList * list, const gchar * tag,
+ guint index)
+{
+ const GValue *value;
+
+ g_return_val_if_fail (GST_IS_TAG_LIST (list), NULL);
+ g_return_val_if_fail (tag != NULL, NULL);
+
+ value = gst_structure_get_value ((GstStructure *) list, tag);
+ if (value == NULL)
+ return NULL;
+
+ if (GST_VALUE_HOLDS_LIST (value)) {
+ if (index >= gst_value_list_get_size (value))
+ return NULL;
+ return gst_value_list_get_value (value, index);
+ } else {
+ if (index > 0)
+ return NULL;
+ return value;
+ }
+}
+
+/**
+ * gst_tag_list_copy_value:
+ * @dest: uninitialized #GValue to copy into
+ * @list: list to get the tag from
+ * @tag: tag to read out
+ *
+ * Copies the contents for the given tag into the value,
+ * merging multiple values into one if multiple values are associated
+ * with the tag.
+ * You must g_value_unset() the value after use.
+ *
+ * Returns: TRUE, if a value was copied, FALSE if the tag didn't exist in the
+ * given list.
+ */
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+
+gboolean
+gst_tag_list_copy_value (GValue * dest, const GstTagList * list,
+ const gchar * tag)
+{
+ const GValue *src;
+
+ g_return_val_if_fail (GST_IS_TAG_LIST (list), FALSE);
+ g_return_val_if_fail (tag != NULL, FALSE);
+ g_return_val_if_fail (dest != NULL, FALSE);
+ g_return_val_if_fail (G_VALUE_TYPE (dest) == 0, FALSE);
+
+ src = gst_structure_get_value ((GstStructure *) list, tag);
+ if (!src)
+ return FALSE;
+
+ if (G_VALUE_TYPE (src) == GST_TYPE_LIST) {
+ GstTagInfo *info = gst_tag_lookup (g_quark_from_string (tag));
+
+ /* must be there or lists aren't allowed */
+ g_assert (info->merge_func);
+ info->merge_func (dest, src);
+ } else {
+ g_value_init (dest, G_VALUE_TYPE (src));
+ g_value_copy (src, dest);
+ }
+ return TRUE;
+}
+
+/* FIXME 0.11: this whole merge function business is overdesigned, and the
+ * _get_foo() API is misleading as well - how many application developers will
+ * expect gst_tag_list_get_string (list, GST_TAG_ARTIST, &val) might return a
+ * string with multiple comma-separated artists? _get_foo() should just be
+ * a convenience wrapper around _get_foo_index (list, tag, 0, &val),
+ * supplemented by a special _tag_list_get_string_merged() function if needed
+ * (unless someone can actually think of real use cases where the merge
+ * function is not 'use first' for non-strings and merge for strings) */
+
+/***** evil macros to get all the gst_tag_list_get_*() functions right *****/
+
+#define TAG_MERGE_FUNCS(name,type) \
+gboolean \
+__declspec(dllexport) gst_tag_list_get_ ## name (const GstTagList *list, const gchar *tag, \
+ type *value) \
+{ \
+ GValue v = { 0, }; \
+ \
+ g_return_val_if_fail (GST_IS_TAG_LIST (list), FALSE); \
+ g_return_val_if_fail (tag != NULL, FALSE); \
+ g_return_val_if_fail (value != NULL, FALSE); \
+ \
+ if (!gst_tag_list_copy_value (&v, list, tag)) \
+ return FALSE; \
+ *value = COPY_FUNC (g_value_get_ ## name (&v)); \
+ g_value_unset (&v); \
+ return TRUE; \
+} \
+ \
+__declspec(dllexport) gboolean \
+gst_tag_list_get_ ## name ## _index (const GstTagList *list, \
+ const gchar *tag, \
+ guint index, type *value) \
+{ \
+ const GValue *v; \
+ \
+ g_return_val_if_fail (GST_IS_TAG_LIST (list), FALSE); \
+ g_return_val_if_fail (tag != NULL, FALSE); \
+ g_return_val_if_fail (value != NULL, FALSE); \
+ \
+ if ((v = gst_tag_list_get_value_index (list, tag, index)) == NULL) \
+ return FALSE; \
+ *value = COPY_FUNC (g_value_get_ ## name (v)); \
+ return TRUE; \
+}
+
+/* FIXME 0.11: maybe get rid of _get_char*(), _get_uchar*(), _get_long*(),
+ * _get_ulong*() and _get_pointer*()? - they are not really useful/common
+ * enough to warrant convenience accessor functions */
+
+#define COPY_FUNC /**/
+/**
+ * gst_tag_list_get_char:
+ * @list: a #GstTagList to get the tag from
+ * @tag: tag to read out
+ * @value: location for the result
+ *
+ * Copies the contents for the given tag into the value, merging multiple values
+ * into one if multiple values are associated with the tag.
+ *
+ * Returns: TRUE, if a value was copied, FALSE if the tag didn't exist in the
+ * given list.
+ */
+/**
+ * gst_tag_list_get_char_index:
+ * @list: a #GstTagList to get the tag from
+ * @tag: tag to read out
+ * @index: number of entry to read out
+ * @value: location for the result
+ *
+ * Gets the value that is at the given index for the given tag in the given
+ * list.
+ *
+ * Returns: TRUE, if a value was copied, FALSE if the tag didn't exist in the
+ * given list.
+ */
+TAG_MERGE_FUNCS (char, gchar)
+/**
+ * gst_tag_list_get_uchar:
+ * @list: a #GstTagList to get the tag from
+ * @tag: tag to read out
+ * @value: location for the result
+ *
+ * Copies the contents for the given tag into the value, merging multiple values
+ * into one if multiple values are associated with the tag.
+ *
+ * Returns: TRUE, if a value was copied, FALSE if the tag didn't exist in the
+ * given list.
+ */
+/**
+ * gst_tag_list_get_uchar_index:
+ * @list: a #GstTagList to get the tag from
+ * @tag: tag to read out
+ * @index: number of entry to read out
+ * @value: location for the result
+ *
+ * Gets the value that is at the given index for the given tag in the given
+ * list.
+ *
+ * Returns: TRUE, if a value was copied, FALSE if the tag didn't exist in the
+ * given list.
+ */
+TAG_MERGE_FUNCS (uchar, guchar)
+/**
+ * gst_tag_list_get_boolean:
+ * @list: a #GstTagList to get the tag from
+ * @tag: tag to read out
+ * @value: location for the result
+ *
+ * Copies the contents for the given tag into the value, merging multiple values
+ * into one if multiple values are associated with the tag.
+ *
+ * Returns: TRUE, if a value was copied, FALSE if the tag didn't exist in the
+ * given list.
+ */
+/**
+ * gst_tag_list_get_boolean_index:
+ * @list: a #GstTagList to get the tag from
+ * @tag: tag to read out
+ * @index: number of entry to read out
+ * @value: location for the result
+ *
+ * Gets the value that is at the given index for the given tag in the given
+ * list.
+ *
+ * Returns: TRUE, if a value was copied, FALSE if the tag didn't exist in the
+ * given list.
+ */
+TAG_MERGE_FUNCS (boolean, gboolean)
+/**
+ * gst_tag_list_get_int:
+ * @list: a #GstTagList to get the tag from
+ * @tag: tag to read out
+ * @value: location for the result
+ *
+ * Copies the contents for the given tag into the value, merging multiple values
+ * into one if multiple values are associated with the tag.
+ *
+ * Returns: TRUE, if a value was copied, FALSE if the tag didn't exist in the
+ * given list.
+ */
+/**
+ * gst_tag_list_get_int_index:
+ * @list: a #GstTagList to get the tag from
+ * @tag: tag to read out
+ * @index: number of entry to read out
+ * @value: location for the result
+ *
+ * Gets the value that is at the given index for the given tag in the given
+ * list.
+ *
+ * Returns: TRUE, if a value was copied, FALSE if the tag didn't exist in the
+ * given list.
+ */
+TAG_MERGE_FUNCS (int, gint)
+/**
+ * gst_tag_list_get_uint:
+ * @list: a #GstTagList to get the tag from
+ * @tag: tag to read out
+ * @value: location for the result
+ *
+ * Copies the contents for the given tag into the value, merging multiple values
+ * into one if multiple values are associated with the tag.
+ *
+ * Returns: TRUE, if a value was copied, FALSE if the tag didn't exist in the
+ * given list.
+ */
+/**
+ * gst_tag_list_get_uint_index:
+ * @list: a #GstTagList to get the tag from
+ * @tag: tag to read out
+ * @index: number of entry to read out
+ * @value: location for the result
+ *
+ * Gets the value that is at the given index for the given tag in the given
+ * list.
+ *
+ * Returns: TRUE, if a value was copied, FALSE if the tag didn't exist in the
+ * given list.
+ */
+TAG_MERGE_FUNCS (uint, guint)
+/**
+ * gst_tag_list_get_long:
+ * @list: a #GstTagList to get the tag from
+ * @tag: tag to read out
+ * @value: location for the result
+ *
+ * Copies the contents for the given tag into the value, merging multiple values
+ * into one if multiple values are associated with the tag.
+ *
+ * Returns: TRUE, if a value was copied, FALSE if the tag didn't exist in the
+ * given list.
+ */
+/**
+ * gst_tag_list_get_long_index:
+ * @list: a #GstTagList to get the tag from
+ * @tag: tag to read out
+ * @index: number of entry to read out
+ * @value: location for the result
+ *
+ * Gets the value that is at the given index for the given tag in the given
+ * list.
+ *
+ * Returns: TRUE, if a value was copied, FALSE if the tag didn't exist in the
+ * given list.
+ */
+TAG_MERGE_FUNCS (long, glong)
+/**
+ * gst_tag_list_get_ulong:
+ * @list: a #GstTagList to get the tag from
+ * @tag: tag to read out
+ * @value: location for the result
+ *
+ * Copies the contents for the given tag into the value, merging multiple values
+ * into one if multiple values are associated with the tag.
+ *
+ * Returns: TRUE, if a value was copied, FALSE if the tag didn't exist in the
+ * given list.
+ */
+/**
+ * gst_tag_list_get_ulong_index:
+ * @list: a #GstTagList to get the tag from
+ * @tag: tag to read out
+ * @index: number of entry to read out
+ * @value: location for the result
+ *
+ * Gets the value that is at the given index for the given tag in the given
+ * list.
+ *
+ * Returns: TRUE, if a value was copied, FALSE if the tag didn't exist in the
+ * given list.
+ */
+TAG_MERGE_FUNCS (ulong, gulong)
+/**
+ * gst_tag_list_get_int64:
+ * @list: a #GstTagList to get the tag from
+ * @tag: tag to read out
+ * @value: location for the result
+ *
+ * Copies the contents for the given tag into the value, merging multiple values
+ * into one if multiple values are associated with the tag.
+ *
+ * Returns: TRUE, if a value was copied, FALSE if the tag didn't exist in the
+ * given list.
+ */
+/**
+ * gst_tag_list_get_int64_index:
+ * @list: a #GstTagList to get the tag from
+ * @tag: tag to read out
+ * @index: number of entry to read out
+ * @value: location for the result
+ *
+ * Gets the value that is at the given index for the given tag in the given
+ * list.
+ *
+ * Returns: TRUE, if a value was copied, FALSE if the tag didn't exist in the
+ * given list.
+ */
+TAG_MERGE_FUNCS (int64, gint64)
+/**
+ * gst_tag_list_get_uint64:
+ * @list: a #GstTagList to get the tag from
+ * @tag: tag to read out
+ * @value: location for the result
+ *
+ * Copies the contents for the given tag into the value, merging multiple values
+ * into one if multiple values are associated with the tag.
+ *
+ * Returns: TRUE, if a value was copied, FALSE if the tag didn't exist in the
+ * given list.
+ */
+/**
+ * gst_tag_list_get_uint64_index:
+ * @list: a #GstTagList to get the tag from
+ * @tag: tag to read out
+ * @index: number of entry to read out
+ * @value: location for the result
+ *
+ * Gets the value that is at the given index for the given tag in the given
+ * list.
+ *
+ * Returns: TRUE, if a value was copied, FALSE if the tag didn't exist in the
+ * given list.
+ */
+TAG_MERGE_FUNCS (uint64, guint64)
+/**
+ * gst_tag_list_get_float:
+ * @list: a #GstTagList to get the tag from
+ * @tag: tag to read out
+ * @value: location for the result
+ *
+ * Copies the contents for the given tag into the value, merging multiple values
+ * into one if multiple values are associated with the tag.
+ *
+ * Returns: TRUE, if a value was copied, FALSE if the tag didn't exist in the
+ * given list.
+ */
+/**
+ * gst_tag_list_get_float_index:
+ * @list: a #GstTagList to get the tag from
+ * @tag: tag to read out
+ * @index: number of entry to read out
+ * @value: location for the result
+ *
+ * Gets the value that is at the given index for the given tag in the given
+ * list.
+ *
+ * Returns: TRUE, if a value was copied, FALSE if the tag didn't exist in the
+ * given list.
+ */
+TAG_MERGE_FUNCS (float, gfloat)
+/**
+ * gst_tag_list_get_double:
+ * @list: a #GstTagList to get the tag from
+ * @tag: tag to read out
+ * @value: location for the result
+ *
+ * Copies the contents for the given tag into the value, merging multiple values
+ * into one if multiple values are associated with the tag.
+ *
+ * Returns: TRUE, if a value was copied, FALSE if the tag didn't exist in the
+ * given list.
+ */
+/**
+ * gst_tag_list_get_double_index:
+ * @list: a #GstTagList to get the tag from
+ * @tag: tag to read out
+ * @index: number of entry to read out
+ * @value: location for the result
+ *
+ * Gets the value that is at the given index for the given tag in the given
+ * list.
+ *
+ * Returns: TRUE, if a value was copied, FALSE if the tag didn't exist in the
+ * given list.
+ */
+TAG_MERGE_FUNCS (double, gdouble)
+/**
+ * gst_tag_list_get_pointer:
+ * @list: a #GstTagList to get the tag from
+ * @tag: tag to read out
+ * @value: location for the result
+ *
+ * Copies the contents for the given tag into the value, merging multiple values
+ * into one if multiple values are associated with the tag.
+ *
+ * Returns: TRUE, if a value was copied, FALSE if the tag didn't exist in the
+ * given list.
+ */
+/**
+ * gst_tag_list_get_pointer_index:
+ * @list: a #GstTagList to get the tag from
+ * @tag: tag to read out
+ * @index: number of entry to read out
+ * @value: location for the result
+ *
+ * Gets the value that is at the given index for the given tag in the given
+ * list.
+ *
+ * Returns: TRUE, if a value was copied, FALSE if the tag didn't exist in the
+ * given list.
+ */
+TAG_MERGE_FUNCS (pointer, gpointer)
+#undef COPY_FUNC
+#define COPY_FUNC g_strdup
+/**
+ * gst_tag_list_get_string:
+ * @list: a #GstTagList to get the tag from
+ * @tag: tag to read out
+ * @value: location for the result
+ *
+ * Copies the contents for the given tag into the value, possibly merging
+ * multiple values into one if multiple values are associated with the tag.
+ *
+ * Use gst_tag_list_get_string_index (list, tag, 0, value) if you want
+ * to retrieve the first string associated with this tag unmodified.
+ *
+ * The resulting string in @value will be in UTF-8 encoding and should be
+ * freed by the caller using g_free when no longer needed.
+ *
+ * Returns: TRUE, if a value was copied, FALSE if the tag didn't exist in the
+ * given list.
+ */
+/**
+ * gst_tag_list_get_string_index:
+ * @list: a #GstTagList to get the tag from
+ * @tag: tag to read out
+ * @index: number of entry to read out
+ * @value: location for the result
+ *
+ * Gets the value that is at the given index for the given tag in the given
+ * list.
+ *
+ * The resulting string in @value will be in UTF-8 encoding and should be
+ * freed by the caller using g_free when no longer needed.
+ *
+ * Returns: TRUE, if a value was copied, FALSE if the tag didn't exist in the
+ * given list.
+ */
+TAG_MERGE_FUNCS (string, gchar *)
+
+/**
+ * gst_tag_list_get_date:
+ * @list: a #GstTagList to get the tag from
+ * @tag: tag to read out
+ * @value: location for the result
+ *
+ * Copies the contents for the given tag into the value, merging multiple values
+ * into one if multiple values are associated with the tag.
+ *
+ * Returns: TRUE, if a value was copied, FALSE if the tag didn't exist in the
+ * given list or if it was #NULL.
+ */
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+
+gboolean
+gst_tag_list_get_date (const GstTagList * list, const gchar * tag,
+ GDate ** value)
+{
+ GValue v = { 0, };
+
+ g_return_val_if_fail (GST_IS_TAG_LIST (list), FALSE);
+ g_return_val_if_fail (tag != NULL, FALSE);
+ g_return_val_if_fail (value != NULL, FALSE);
+
+ if (!gst_tag_list_copy_value (&v, list, tag))
+ return FALSE;
+ *value = (GDate *) g_value_dup_boxed (&v);
+ g_value_unset (&v);
+ return (*value != NULL);
+}
+
+/**
+ * gst_tag_list_get_date_index:
+ * @list: a #GstTagList to get the tag from
+ * @tag: tag to read out
+ * @index: number of entry to read out
+ * @value: location for the result
+ *
+ * Gets the value that is at the given index for the given tag in the given
+ * list.
+ *
+ * Returns: TRUE, if a value was copied, FALSE if the tag didn't exist in the
+ * given list or if it was #NULL.
+ */
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+
+gboolean
+gst_tag_list_get_date_index (const GstTagList * list,
+ const gchar * tag, guint index, GDate ** value)
+{
+ const GValue *v;
+
+ g_return_val_if_fail (GST_IS_TAG_LIST (list), FALSE);
+ g_return_val_if_fail (tag != NULL, FALSE);
+ g_return_val_if_fail (value != NULL, FALSE);
+
+ if ((v = gst_tag_list_get_value_index (list, tag, index)) == NULL)
+ return FALSE;
+ *value = (GDate *) g_value_dup_boxed (v);
+ return (*value != NULL);
+}