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Diffstat (limited to 'src/sticker/StickerDatabase.hxx')
-rw-r--r-- | src/sticker/StickerDatabase.hxx | 161 |
1 files changed, 161 insertions, 0 deletions
diff --git a/src/sticker/StickerDatabase.hxx b/src/sticker/StickerDatabase.hxx new file mode 100644 index 000000000..8993489c4 --- /dev/null +++ b/src/sticker/StickerDatabase.hxx @@ -0,0 +1,161 @@ +/* + * Copyright (C) 2003-2014 The Music Player Daemon Project + * http://www.musicpd.org + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program 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 General Public License for more details. + * + * You should have received a copy of the GNU General Public License along + * with this program; if not, write to the Free Software Foundation, Inc., + * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. + */ + +/* + * This is the sticker database library. It is the backend of all the + * sticker code in MPD. + * + * "Stickers" are pieces of information attached to existing MPD + * objects (e.g. song files, directories, albums). Clients can create + * arbitrary name/value pairs. MPD itself does not assume any special + * meaning in them. + * + * The goal is to allow clients to share additional (possibly dynamic) + * information about songs, which is neither stored on the client (not + * available to other clients), nor stored in the song files (MPD has + * no write access). + * + * Client developers should create a standard for common sticker + * names, to ensure interoperability. + * + * Examples: song ratings; statistics; deferred tag writes; lyrics; + * ... + * + */ + +#ifndef MPD_STICKER_DATABASE_HXX +#define MPD_STICKER_DATABASE_HXX + +#include "Compiler.h" + +#include <string> + +class Error; +class Path; +struct sticker; + +/** + * Opens the sticker database. + * + * @return true on success, false on error + */ +bool +sticker_global_init(Path path, Error &error); + +/** + * Close the sticker database. + */ +void +sticker_global_finish(void); + +/** + * Returns true if the sticker database is configured and available. + */ +gcc_const +bool +sticker_enabled(void); + +/** + * Returns one value from an object's sticker record. Returns an + * empty string if the value doesn't exist. + */ +std::string +sticker_load_value(const char *type, const char *uri, const char *name); + +/** + * Sets a sticker value in the specified object. Overwrites existing + * values. + */ +bool +sticker_store_value(const char *type, const char *uri, + const char *name, const char *value); + +/** + * Deletes a sticker from the database. All sticker values of the + * specified object are deleted. + */ +bool +sticker_delete(const char *type, const char *uri); + +/** + * Deletes a sticker value. Fails if no sticker with this name + * exists. + */ +bool +sticker_delete_value(const char *type, const char *uri, const char *name); + +/** + * Frees resources held by the sticker object. + * + * @param sticker the sticker object to be freed + */ +void +sticker_free(sticker *sticker); + +/** + * Determines a single value in a sticker. + * + * @param sticker the sticker object + * @param name the name of the sticker + * @return the sticker value, or nullptr if none was found + */ +gcc_pure +const char * +sticker_get_value(const sticker &sticker, const char *name); + +/** + * Iterates over all sticker items in a sticker. + * + * @param sticker the sticker object + * @param func a callback function + * @param user_data an opaque pointer for the callback function + */ +void +sticker_foreach(const sticker &sticker, + void (*func)(const char *name, const char *value, + void *user_data), + void *user_data); + +/** + * Loads the sticker for the specified resource. + * + * @param type the resource type, e.g. "song" + * @param uri the URI of the resource, e.g. the song path + * @return a sticker object, or nullptr on error or if there is no sticker + */ +sticker * +sticker_load(const char *type, const char *uri); + +/** + * Finds stickers with the specified name below the specified URI. + * + * @param type the resource type, e.g. "song" + * @param base_uri the URI prefix of the resources, or nullptr if all + * resources should be searched + * @param name the name of the sticker + * @return true on success (even if no sticker was found), false on + * failure + */ +bool +sticker_find(const char *type, const char *base_uri, const char *name, + void (*func)(const char *uri, const char *value, + void *user_data), + void *user_data); + +#endif |