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/*
* Copyright (C) 2003-2011 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.
*/
/** \file
*
* This header declares the db_plugin class. It describes a
* plugin API for databases of song metadata.
*/
#ifndef MPD_DB_PLUGIN_H
#define MPD_DB_PLUGIN_H
#include <glib.h>
#include <assert.h>
#include <stdbool.h>
struct config_param;
struct db_selection;
struct db_visitor;
struct db {
const struct db_plugin *plugin;
};
struct db_plugin {
const char *name;
/**
* Allocates and configures a database.
*/
struct db *(*init)(const struct config_param *param, GError **error_r);
/**
* Free instance data.
*/
void (*finish)(struct db *db);
/**
* Open the database. Read it into memory if applicable.
*/
bool (*open)(struct db *db, GError **error_r);
/**
* Close the database, free allocated memory.
*/
void (*close)(struct db *db);
/**
* Look up a song (including tag data) in the database.
*
* @param the URI of the song within the music directory
* (UTF-8)
*/
struct song *(*get_song)(struct db *db, const char *uri,
GError **error_r);
/**
* Visit the selected entities.
*/
bool (*visit)(struct db *db, const struct db_selection *selection,
const struct db_visitor *visitor, void *ctx,
GError **error_r);
};
G_GNUC_MALLOC
static inline struct db *
db_plugin_new(const struct db_plugin *plugin, const struct config_param *param,
GError **error_r)
{
assert(plugin != NULL);
assert(plugin->init != NULL);
assert(plugin->finish != NULL);
assert(plugin->get_song != NULL);
assert(plugin->visit != NULL);
assert(error_r == NULL || *error_r == NULL);
struct db *db = plugin->init(param, error_r);
assert(db == NULL || db->plugin == plugin);
assert(db != NULL || error_r == NULL || *error_r != NULL);
return db;
}
static inline void
db_plugin_free(struct db *db)
{
assert(db != NULL);
assert(db->plugin != NULL);
assert(db->plugin->finish != NULL);
db->plugin->finish(db);
}
static inline bool
db_plugin_open(struct db *db, GError **error_r)
{
assert(db != NULL);
assert(db->plugin != NULL);
return db->plugin->open != NULL
? db->plugin->open(db, error_r)
: true;
}
static inline void
db_plugin_close(struct db *db)
{
assert(db != NULL);
assert(db->plugin != NULL);
if (db->plugin->close != NULL)
db->plugin->close(db);
}
static inline struct song *
db_plugin_get_song(struct db *db, const char *uri, GError **error_r)
{
assert(db != NULL);
assert(db->plugin != NULL);
assert(db->plugin->get_song != NULL);
assert(uri != NULL);
return db->plugin->get_song(db, uri, error_r);
}
static inline bool
db_plugin_visit(struct db *db, const struct db_selection *selection,
const struct db_visitor *visitor, void *ctx,
GError **error_r)
{
assert(db != NULL);
assert(db->plugin != NULL);
assert(selection != NULL);
assert(visitor != NULL);
assert(error_r == NULL || *error_r == NULL);
return db->plugin->visit(db, selection, visitor, ctx, error_r);
}
#endif
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