/*
 * CallWeaver -- An open source telephony toolkit.
 *
 * Copyright (C) 2007-2008, Eris Associates Ltd, UK
 *
 * Mike Jagdis <mjagdis@eris-associates.co.uk>
 *
 * See http://www.callweaver.org for more information about
 * the CallWeaver project. Please do not directly contact
 * any of the maintainers of this project for assistance;
 * the project provides a web site, mailing lists and IRC
 * channels for your use.
 *
 * This program is free software, distributed under the terms of
 * the GNU General Public License Version 2. See the LICENSE file
 * at the top of the source tree.
 */

/*! \file
 * \brief Registry API 
 */

#ifndef _CALLWEAVER_REGISTRY_H
#define _CALLWEAVER_REGISTRY_H

#include "callweaver/lock.h"
#include "callweaver/atomic.h"


struct cw_list {
	struct cw_list *next, *prev, *del;
};

#define LIST_INIT(name) { &(name), &(name), NULL }

static inline void cw_list_init(struct cw_list *list) {
	list->next = list->prev = list;
	list->del = NULL;
}

static inline void __cw_list_add(struct cw_list *prev, struct cw_list *entry, struct cw_list *next)
{
	next->prev = entry;
	entry->next = next;
	entry->prev = prev;
	prev->next = entry;
}

static inline void cw_list_add(struct cw_list *head, struct cw_list *entry)
{
	__cw_list_add(head, entry, head->next);
}

static inline void __cw_list_del(struct cw_list *prev, struct cw_list *next)
{
	next->prev = prev;
	prev->next = next;
}

static inline void cw_list_del(struct cw_list **del, struct cw_list *entry)
{
	if (!entry->del) {
		__cw_list_del(entry->prev, entry->next);
		entry->del = *del;
		*del = entry;
	}
}

#define cw_list_for_each(var, head) \
	for (var = (head)->next; var != (head); var = var->next)

#define cw_list_for_each_rev(var, head) \
	for (var = (head)->prev; var != (head); var = var->prev)


struct cw_object;


struct cw_registry_entry {
	struct cw_list list;
	struct cw_object *obj;
	unsigned int hash;
};

struct cw_registry {
	pthread_spinlock_t lock;
	atomic_t inuse;
	size_t size;
	struct cw_list *list;
	struct cw_list *del;
	int entries;
	int (*qsort_compare)(const void *a, const void *b);
	int (*match)(struct cw_object *obj, const void *pattern);
	char *name;
	void (*onchange)(void);
};


/*! \brief Add an object to a registry
 *
 * \param registry	the registry the object is to be added to
 * \param hash		a hash of the object key
 * \param obj		the object to add
 */
extern CW_API_PUBLIC struct cw_registry_entry *cw_registry_add(struct cw_registry *registry, unsigned int hash, struct cw_object *obj);

/*! \brief Delete an object from a registry
 *
 * \param registry	the registry the object is to be deleted from
 * \param entry		the registry entry to be deleted
 */
extern CW_API_PUBLIC int cw_registry_del(struct cw_registry *registry, struct cw_registry_entry *entry);

extern CW_API_PUBLIC int cw_registry_replace(struct cw_registry *registry, unsigned int hash, const void *pattern, struct cw_object *obj);

extern CW_API_PUBLIC int cw_registry_iterate(struct cw_registry *registry, int (*func)(struct cw_object *, void *), void *data);
extern CW_API_PUBLIC int cw_registry_iterate_rev(struct cw_registry *registry, int (*func)(struct cw_object *, void *), void *data);
extern CW_API_PUBLIC int cw_registry_iterate_ordered(struct cw_registry *registry, int (*func)(struct cw_object *, void *), void *data);

extern CW_API_PUBLIC struct cw_object *cw_registry_find(struct cw_registry *registry, int have_hash, unsigned int hash, const void *pattern);
extern CW_API_PUBLIC int cw_registry_init(struct cw_registry *registry, size_t estsize);
extern CW_API_PUBLIC void cw_registry_flush(struct cw_registry *registry);
extern CW_API_PUBLIC void cw_registry_destroy(struct cw_registry *registry);


#endif /* _CALLWEAVER_REGISTRY_H */