/* GStreamer * Copyright (C) 2003 Benjamin Otte * * gsttag.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. */ #ifdef HAVE_CONFIG_H # include "config.h" #endif #include "gst_private.h" #include "gsttag.h" #include "gstinfo.h" #include "gstvalue.h" #include #include #define GST_TAG_IS_VALID(tag) (gst_tag_get_info (tag) != NULL) 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 */ } 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) 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, G_TYPE_STRING, _("title"), _("commonly used title"), gst_tag_merge_strings_with_comma); gst_tag_register (GST_TAG_ARTIST, G_TYPE_STRING, _("artist"), _("person(s) resposible for the recording"), gst_tag_merge_strings_with_comma); gst_tag_register (GST_TAG_ALBUM, G_TYPE_STRING, _("album"), _("album containing this data"), gst_tag_merge_strings_with_comma); gst_tag_register (GST_TAG_DATE, G_TYPE_UINT, /* FIXME: own data type for dates? */ _("date"), _("date the data was created in julien days"), NULL); gst_tag_register (GST_TAG_GENRE, G_TYPE_STRING, _("genre"), _("genre this data belongs to"), gst_tag_merge_strings_with_comma); gst_tag_register (GST_TAG_COMMENT, G_TYPE_STRING, _("comment"), _("free text commenting the data"), gst_tag_merge_strings_with_comma); gst_tag_register (GST_TAG_TRACK_NUMBER, G_TYPE_UINT, _("track number"), _("track number inside a collection"), gst_tag_merge_use_first); gst_tag_register (GST_TAG_TRACK_COUNT, G_TYPE_STRING, _("track count"), _("count of tracks inside collection this track belongs to"), gst_tag_merge_use_first); gst_tag_register (GST_TAG_LOCATION, G_TYPE_STRING, _("loccation"), _("original location of file as a URI"), gst_tag_merge_strings_with_comma); gst_tag_register (GST_TAG_DESCRIPTION, G_TYPE_STRING, _("description"), _("short text describing the content of the data"), gst_tag_merge_strings_with_comma); gst_tag_register (GST_TAG_VERSION, G_TYPE_STRING, _("version"), _("version of this data"), NULL); gst_tag_register (GST_TAG_ISRC, G_TYPE_STRING, _("ISRC"), _("International Standard Recording Code - see http://www.ifpi.org/isrc/"), NULL); gst_tag_register (GST_TAG_ORGANIZATION, G_TYPE_STRING, _("organization"), _("organization"), /* FIXME */ gst_tag_merge_strings_with_comma); gst_tag_register (GST_TAG_COPYRIGHT, G_TYPE_STRING, _("copyright"), _("copyright notice of the data"), NULL); gst_tag_register (GST_TAG_CONTACT, G_TYPE_STRING, _("contact"), _("contact information"), gst_tag_merge_strings_with_comma); gst_tag_register (GST_TAG_LICENSE, G_TYPE_STRING, _("license"), _("license of data"), NULL); gst_tag_register (GST_TAG_PERFORMER, G_TYPE_STRING, _("performer"), _("person(s) performing"), gst_tag_merge_strings_with_comma); gst_tag_register (GST_TAG_DURATION, G_TYPE_UINT64, _("duration"), _("length in GStreamer time units (nanoseconds)"), NULL); gst_tag_register (GST_TAG_CODEC, G_TYPE_STRING, _("codec"), _("codec the data is stored in"), gst_tag_merge_strings_with_comma); gst_tag_register (GST_TAG_MINIMUM_BITRATE, G_TYPE_UINT, _("minimum bitrate"), _("minimum bitrate in bits/s"), NULL); gst_tag_register (GST_TAG_BITRATE, G_TYPE_UINT, _("bitrate"), _("exact or average bitrate in bits/s"), NULL); gst_tag_register (GST_TAG_MAXIMUM_BITRATE, G_TYPE_UINT, _("maximum bitrate"), _("maximum bitrate in bits/s"), 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. */ 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. */ 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_take_string (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 * @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 * * 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 youre supplied values. * If you know the type is already registered, use gst_tag_lookup instead. * This function takes ownership of all supplied variables. */ void gst_tag_register (gchar *name, GType type, gchar *nick, 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_VALUE_TYPE_LIST); key = g_quark_from_string (name); info = gst_tag_lookup (key); g_return_if_fail (info == NULL); info = g_new (GstTagInfo, 1); info->type = type; info->nick = nick; info->blurb = 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 */ 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 */ 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 */ 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. * * Return the human-readable description of this tag */ 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_list_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. */ 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 */ GstTagList * gst_tag_list_new (void) { return GST_TAG_LIST (gst_structure_new (TAGLIST, NULL)); } /** * 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 */ gboolean gst_is_tag_list (gconstpointer p) { g_return_val_if_fail (p != NULL, FALSE); return ((GstStructure *) p)->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, GValue *value) { GstTagInfo *info = gst_tag_lookup (tag); GstStructureField *field; g_assert (info != NULL); if (info->merge_func && (field = gst_structure_id_get_field (list, tag)) != NULL) { GValue value2 = { 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 (&value2, value, &field->value); gst_structure_id_set_value (list, tag, &value2); g_value_unset (&value2); break; case GST_TAG_MERGE_APPEND: gst_value_list_concat (&value2, &field->value, value); gst_structure_id_set_value (list, tag, &value2); g_value_unset (&value2); 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_field (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 void gst_tag_list_copy_foreach (GstStructure *structure, GQuark tag, GValue *value, gpointer user_data) { GstTagCopyData *copy = (GstTagCopyData *) user_data; gst_tag_list_add_value_internal (copy->list, copy->mode, tag, value); } /** * 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. */ 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_field_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 */ 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 */ 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. */ 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 */ 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_VALUE_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 * @...: values to set * * Sets the values for the given tags using the specified mode. */ 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_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. */ 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); 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_remove_tag: * @list: list to remove tag from * @tag: tag to remove * * Removes the goven tag from the taglist. */ 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; gpointer data; } TagForeachData; static void structure_foreach_wrapper (GstStructure *structure, GQuark field_id, GValue *value, gpointer user_data) { TagForeachData *data = (TagForeachData *) user_data; data->func (GST_TAG_LIST (structure), g_quark_to_string (field_id), data->data); } /** * 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. */ void gst_tag_list_foreach (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.data = user_data; gst_structure_field_foreach ((GstStructure *) list, structure_foreach_wrapper, &data); } /***** tag events *****/ /** * gst_event_new_tag: * @list: the tag list to put into the event or NULL for an empty list * * Creates a new tag event with the given list and takes ownership of it. * * Returns: a new tag event */ GstEvent * gst_event_new_tag (GstTagList *list) { GstEvent *ret; g_return_val_if_fail (list == NULL || GST_IS_TAG_LIST (list), NULL); ret = gst_event_new (GST_EVENT_TAG); if (!list) list = gst_tag_list_new (); ret->event_data.structure.structure = (GstStructure *) list; return ret; } /** * get_event_tag_get_list: * @tag_event: a tagging #GstEvent * * Gets the taglist from a given tagging event. * * Returns: The #GstTagList of the event */ GstTagList * gst_event_tag_get_list (GstEvent *tag_event) { g_return_val_if_fail (GST_IS_EVENT (tag_event), NULL); g_return_val_if_fail (GST_EVENT_TYPE (tag_event) == GST_EVENT_TAG, NULL); return GST_TAG_LIST (tag_event->event_data.structure.structure); } /** * 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 */ 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. */ 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_VALUE_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; } /***** evil macros to get all the gst_tag_list_get_*() functions right *****/ #define TAG_MERGE_FUNCS(name,type) \ gboolean \ 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; \ } \ \ 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; \ } #define COPY_FUNC /**/ TAG_MERGE_FUNCS (char, gchar) TAG_MERGE_FUNCS (uchar, guchar) TAG_MERGE_FUNCS (boolean, gboolean) TAG_MERGE_FUNCS (int, gint) TAG_MERGE_FUNCS (uint, guint) TAG_MERGE_FUNCS (long, glong) TAG_MERGE_FUNCS (ulong, gulong) TAG_MERGE_FUNCS (int64, gint64) TAG_MERGE_FUNCS (uint64, guint64) TAG_MERGE_FUNCS (float, gfloat) TAG_MERGE_FUNCS (double, gdouble) #undef COPY_FUNC #define COPY_FUNC g_strdup TAG_MERGE_FUNCS (string, gchar *)