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/*
* (c) 2004-2008 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#ifndef PLUGIN_H
#define PLUGIN_H
#include <glib.h>
#include <stdbool.h>
/**
* A list of registered plugins.
*/
struct plugin_list {
GPtrArray *plugins;
};
/**
* When a plugin cycle is finished, this function is called. In any
* case, plugin_stop() has to be called to free all memory.
*
* @param result the plugin's output (stdout) on success; NULL on failure
* @param data the caller defined pointer passed to plugin_run()
*/
typedef void (*plugin_callback_t)(const GString *result, void *data);
/**
* This object represents a cycle through all available plugins, until
* a plugin returns a positive result.
*/
struct plugin_cycle;
/**
* Initialize an empty plugin_list structure.
*/
static inline void
plugin_list_init(struct plugin_list *list)
{
list->plugins = g_ptr_array_new();
}
/**
* Load all plugins (executables) in a directory.
*/
bool
plugin_list_load_directory(struct plugin_list *list, const char *path);
/**
* Frees all memory held by the plugin_list object (but not the
* pointer itself).
*/
void plugin_list_deinit(struct plugin_list *list);
/**
* Run plugins in this list, until one returns success (or until the
* plugin list is exhausted).
*
* @param list the plugin list
* @param args NULL terminated command line arguments passed to the
* plugin programs
* @param callback the callback function which will be called when a
* result is available
* @param callback_data caller defined pointer which is passed to the
* callback function
*/
struct plugin_cycle *
plugin_run(struct plugin_list *list, const char *const*args,
plugin_callback_t callback, void *callback_data);
/**
* Stops the plugin cycle and frees resources. This can be called to
* abort the current cycle, or after the plugin_callback_t has been
* invoked.
*/
void
plugin_stop(struct plugin_cycle *invocation);
#endif
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