From 6153c86bc3c2c10055143bd85aa3c1ea0dedd769 Mon Sep 17 00:00:00 2001 From: Max Kellermann Date: Sun, 1 Mar 2009 00:55:20 +0100 Subject: tag: added API documentation --- src/tag.h | 65 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 65 insertions(+) (limited to 'src/tag.h') diff --git a/src/tag.h b/src/tag.h index 34f99c0b..760e0b35 100644 --- a/src/tag.h +++ b/src/tag.h @@ -26,6 +26,9 @@ #include #include +/** + * Codes for the type of a tag item. + */ enum tag_type { TAG_ITEM_ARTIST, TAG_ITEM_ALBUM, @@ -48,25 +51,65 @@ enum tag_type { TAG_NUM_OF_ITEM_TYPES }; +/** + * An array of strings, which map the #tag_type to its machine + * readable name (specific to the MPD protocol). + */ extern const char *tag_item_names[]; +/** + * One tag value. It is a mapping of #tag_type to am arbitrary string + * value. Each tag can have multiple items of one tag type (although + * few clients support that). + */ struct tag_item { + /** the type of this item */ enum tag_type type; + + /** + * the value of this tag; this is a variable length string + */ char value[sizeof(long)]; } mpd_packed; +/** + * The meta information about a song file. It is a MPD specific + * subset of tags (e.g. from ID3, vorbis comments, ...). + */ struct tag { + /** + * The duration of the song (in seconds). A value of zero + * means that the length is unknown. If the duration is + * really between zero and one second, you should round up to + * 1. + */ int time; + + /** an array of tag items */ struct tag_item **items; + + /** the total number of tag items in the #items array */ unsigned num_items; }; +/** + * Creates an empty #tag. + */ struct tag *tag_new(void); +/** + * Initializes the tag library. + */ void tag_lib_init(void); +/** + * Clear all tag items with the specified type. + */ void tag_clear_items_by_type(struct tag *tag, enum tag_type type); +/** + * Frees a #tag object and all its items. + */ void tag_free(struct tag *tag); /** @@ -83,15 +126,33 @@ void tag_begin_add(struct tag *tag); */ void tag_end_add(struct tag *tag); +/** + * Appends a new tag item. + * + * @param tag the #tag object + * @param type the type of the new tag item + * @param value the value of the tag item (not null-terminated) + * @param len the length of #value + */ void tag_add_item_n(struct tag *tag, enum tag_type type, const char *value, size_t len); +/** + * Appends a new tag item. + * + * @param tag the #tag object + * @param type the type of the new tag item + * @param value the value of the tag item (null-terminated) + */ static inline void tag_add_item(struct tag *tag, enum tag_type type, const char *value) { tag_add_item_n(tag, type, value, strlen(value)); } +/** + * Duplicates a #tag object. + */ struct tag *tag_dup(const struct tag *tag); /** @@ -135,6 +196,10 @@ tag_get_value(const struct tag *tag, enum tag_type type); */ bool tag_has_type(const struct tag *tag, enum tag_type type); +/** + * Compares two tags, including the duration and all tag items. The + * order of the tag items matters. + */ bool tag_equal(const struct tag *tag1, const struct tag *tag2); #endif -- cgit v1.2.3