/** * @file linked_list.h * * @brief Generic Double Linked List * */ /* * Copyright (C) 2005 Jan Hutter, Martin Willi * Hochschule fuer Technik Rapperswil * * 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. See . * * 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. */ #ifndef LINKED_LIST_H_ #define LINKED_LIST_H_ #include "../types.h" /** * @brief Iterator for a linked list * * This element holds a pointer to the current element in the linked list * * @warning the iterator is NOT thread-save */ typedef struct linked_list_iterator_s linked_list_iterator_t; struct linked_list_iterator_s { /** * @brief returns TRUE if more elements are available * * @param this calling object * @return if more elements are avaiable TRUE, FALSE otherwise */ bool (*has_next) (linked_list_iterator_t *this); /** * @brief returns the current value at the iterator position * * @param this calling object * @param[out] value value is set to the current value at iterator position * @return SUCCESS if succeeded, FAILED otherwise */ status_t (*current) (linked_list_iterator_t *this, void **value); /** * @brief Resets a linked_list_iterator object * * @param this calling object * @return SUCCESS if succeeded, FAILED otherwise */ status_t (*reset) (linked_list_iterator_t *this); /** * @brief Destroys a linked_list_iterator object * * @param this calling object * @return SUCCESS if succeeded, FAILED otherwise */ status_t (*destroy) (linked_list_iterator_t *this); }; /** * @brief Double Linked List (named only as linked list) * * @warning Access to an object of this type is not thread-save * * @see job_queue_t * @see event_queue_t * @see send_queue_t */ typedef struct linked_list_s linked_list_t; struct linked_list_s { /** * @brief gets the count of items in the list * * @param linked_list calling object * @return number of items in list */ int (*get_count) (linked_list_t *linked_list); /** * @brief creates a iterator for the given list * * @warning has to get destroyed * * @param linked_list calling object * @param[out] iterator place where the iterator is written * @param[in] forward iterator direction (TRUE: front to end) * @return SUCCESS if succeeded, FAILED otherwise */ status_t (*create_iterator) (linked_list_t *linked_list, linked_list_iterator_t **iterator,bool forward); /** * @brief inserts a new item at the beginning of the list * * @param linked_list calling object * @param[in] item value to insert in list * @return SUCCESS if succeeded, FAILED otherwise */ status_t (*insert_first) (linked_list_t *linked_list, void *item); /** * @brief inserts a new item before the given iterator position * * The iterator position is not changed after inserting * * @param linked_list calling object * @param iterator new element is inserted before this iterator * @param[in] item value to insert in list * @return SUCCESS if succeeded, FAILED otherwise */ status_t (*insert_before) (linked_list_t *linked_list, linked_list_iterator_t *iterator, void *item); /** * @brief inserts a new item after the given iterator position * * The iterator position is not changed after inserting * * @param linked_list calling object * @param iterator new element is inserted after this iterator * @param[in] item value to insert in list * @return SUCCESS if succeeded, FAILED otherwise */ status_t (*insert_after) (linked_list_t *linked_list, linked_list_iterator_t *iterator, void *item); /** * @brief removes an element from list at the given iterator position * * The position of the iterator is set in the following order: * - to the item before, if available * - otherwise to the item after, if available * - otherwise it gets reseted * * @param linked_list calling object * @param iterator iterator holding the position of the element to remove * @return SUCCESS if succeeded, FAILED otherwise */ status_t (*remove) (linked_list_t *linked_list, linked_list_iterator_t *iterator); /** * @brief removes the first item in the list and returns its value * * @param linked_list calling object * @param[in] item returned value of first item * @return SUCCESS if succeeded, FAILED otherwise */ status_t (*remove_first) (linked_list_t *linked_list, void **item); /** * @brief returns the value of the first list item without removing it * * @param linked_list calling object * @param[out] item returned value of first item * @return SUCCESS if succeeded, FAILED otherwise */ status_t (*get_first) (linked_list_t *linked_list, void **item); /** * @brief inserts a new item at the end of the list * * @param linked_list calling object * @param[in] item value to insert into list * @return SUCCESS if succeeded, FAILED otherwise */ status_t (*insert_last) (linked_list_t *linked_list, void *item); /** * @brief removes the last item in the list and returns its value * * @param linked_list calling object * @param[out] item returned value of last item * @return SUCCESS if succeeded, FAILED otherwise */ status_t (*remove_last) (linked_list_t *linked_list, void **item); /** * @brief Returns the value of the last list item without removing it * * @param linked_list calling object * @param[out] item returned value of last item * @return SUCCESS if succeeded, FAILED otherwise */ status_t (*get_last) (linked_list_t *linked_list, void **item); /** * @brief Destroys a linked_list object * * @warning all items are removed before deleting the list. The * associated values are NOT destroyed. * Destroying an list which is not empty may cause * memory leaks! * * @param linked_list calling object * @return SUCCESS if succeeded, FAILED otherwise */ status_t (*destroy) (linked_list_t *linked_list); }; /** * @brief Creates an empty linked list object */ linked_list_t *linked_list_create(void); #endif /*LINKED_LIST_H_*/