/** \file
 * \brief The linked-list implementation.
 * \note The C equivalent of \c std::list<uintptr_t>
 */
/*
* Copyright (c) 2019-2022 David Timber <dxdt@dev.snart.me>
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in all
* copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*/
#pragma once
#include <stddef.h>
#include <stdbool.h>
#include <stdint.h>


/* Forward and alias declarations */
struct prne_llist;
struct prne_llist_entry;
typedef struct prne_llist prne_llist_t;
typedef struct prne_llist_entry prne_llist_entry_t;
typedef uintptr_t prne_llist_element_t;

struct prne_llist {
	prne_llist_entry_t *head, *tail;
	size_t size;
};

struct prne_llist_entry {
	prne_llist_entry_t *prev, *next;
	prne_llist_element_t element;
};

/**
 * \brief Initialise the linked-list object.
 * \param llist The pointer to the linked-list object.
 * \note \p s can be freed using \c prne_free_llist() once initialised.
 * \see \c prne_free_llist()
 */
void prne_init_llist (prne_llist_t *llist);
/**
 * \brief Free resources allocated for the linked-list object.
 * \param llist The pointer to the linked-list object.
 * \see \c prne_init_llist()
 */
void prne_free_llist (prne_llist_t *llist);
/**
 * \brief Clear the elements of the linked-list object.
 * \param llist The pointer to the linked-list object.
 * \warning The function call may have the exact same effect as
 *	\c prne_free_llist() but \c prne_free_llist() must always be used to free
 *	the resources allocated for the object.
 */
void prne_llist_clear (prne_llist_t *llist);
/**
 * \brief Insert an element after \p entry into the linked-list object.
 * \param llist The pointer to the linked-list object.
 * \param entry The entry that will precede the new entry (optional)
 * \param element The element.
 * \return The pointer to the allocated internal entry object for the element.
 * \retval NULL if a memory allocation error has occurred and \c errno is set
 *	to \c ENOMEM
 * \note If \p entry is passed NULL, the behaviour of the function is the same
 *	is that of prne_llist_append()
 * \see prne_llist_append()
 */
prne_llist_entry_t *prne_llist_insert (
	prne_llist_t *llist,
	prne_llist_entry_t *entry,
	const prne_llist_element_t element);
/**
 * \brief Append an element to the tail of the linked-list object.
 * \param llist The pointer to the linked-list object.
 * \param element The element.
 * \return The pointer to the allocated internal entry object for the element.
 * \retval NULL if a memory allocation error has occurred and \c errno is set
 *	to \c ENOMEM
 * \note This function has the same effect as calling \c prne_llist_insert()
 *	with \c llist->tail
 */
prne_llist_entry_t *prne_llist_append (
	prne_llist_t *llist,
	const prne_llist_element_t element);
/**
 * \brief Remove an element from the linked-list object.
 * \param llist The pointer to the linked-list object.
 * \param entry The pointer to the allocated internal entry object for the
 *	element.
 * \returns The next element of the removed element.
 * \retval NULL if the element removed was the tail or the head.
 */
prne_llist_entry_t *prne_llist_erase (
	prne_llist_t *llist,
	prne_llist_entry_t *entry);