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/*
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
 *
 * Copyright 2021 Mike Becker, Olaf Wintermann All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 *   1. Redistributions of source code must retain the above copyright
 *      notice, this list of conditions and the following disclaimer.
 *
 *   2. Redistributions in binary form must reproduce the above copyright
 *      notice, this list of conditions and the following disclaimer in the
 *      documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */
/**
 * \file linked_list.h
 * \brief Linked list implementation.
 * \details Also provides several low-level functions for custom linked list implementations.
 * \author Mike Becker
 * \author Olaf Wintermann
 * \version 3.0
 * \copyright 2-Clause BSD License
 */

#ifndef UCX_LINKED_LIST_H
#define UCX_LINKED_LIST_H

#include <stddef.h>
#include "list.h"

#ifdef __cplusplus
extern "C" {
#endif

CxList cxLinkedListCreate(CxAllocator allocator, CxListComparator comparator, size_t item_size);

void cxLinkedListDestroy(CxList list);

size_t cxLinkedListRecalculateSize(CxList list);


/**
 * Finds the node at a certain index.
 *
 * This function can be used to start at an arbitrary position within the list.
 * If the search index is large than the start index, \p loc_advance must denote
 * the location of some sort of \c next pointer (i.e. a pointer to the next node).
 * But it is also possible that the search index is smaller than the start index
 * (e.g. in cases where traversing a list backwards is faster) in which case
 * \p loc_advance must denote the location of some sort of \c prev pointer
 * (i.e. a pointer to the previous node).
 *
 * @param start a pointer to the start node
 * @param start_index the start index
 * @param loc_advance the location of the pointer to advance
 * @param index the search index
 * @return the node found at the specified index
 */
void *cx_linked_list_at(void *start, size_t start_index, ptrdiff_t loc_advance, size_t index);

/**
 * Finds the last node in a linked list.
 *
 * If a pointer to \p end is provided, the result is just \c *end.
 * Otherwise, this function starts with the pointer denoted by \c *begin and
 * traverses the list along a next pointer whose location within the node struct is
 * denoted by \p loc_next.
 *
 * If both \p begin and \p end are \c NULL, an empty list is assumed and this function returns \c NULL.
 *
 * @param begin a pointer to the begin node pointer (optional)
 * @param end a pointer to the end node pointer (optional)
 * @param loc_next the location of the \c next pointer (only required when \p end is \c NULL)
 * @return a pointer to the last node or \c NULL if the list is empty
 */
void *cx_linked_list_last(void **begin, void **end, ptrdiff_t loc_next);

/**
 * Adds a new node to a linked list.
 *
 * \remark One of the pointers \p begin and \p end may be \c NULL, but not both.
 *
 * @param begin a pointer to the begin node pointer (if your list has one)
 * @param end a pointer to the end node pointer (if your list has one)
 * @param loc_prev the location of a \c prev pointer within your node struct (negative if your struct does not have one)
 * @param loc_next the location of a \c next pointer within your node struct (negative if your struct does not have one)
 * @param new_node a pointer to the node that shall be appended
 */
void cx_linked_list_add(void **begin, void **end, ptrdiff_t loc_prev, ptrdiff_t loc_next, void *new_node);

#ifdef __cplusplus
} /* extern "C" */
#endif

#endif /* UCX_LINKED_LIST_H */