| /* |
| * Copyright (c) 2014, Mentor Graphics Corporation |
| * Copyright 2019 NXP |
| * 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. |
| * 3. Neither the name of Mentor Graphics Corporation nor the names of its |
| * contributors may be used to endorse or promote products derived from this |
| * software without specific prior written permission. |
| * |
| * 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 NAME |
| * |
| * llist.c |
| * |
| * COMPONENT |
| * |
| * OpenAMP stack. |
| * |
| * DESCRIPTION |
| * |
| * Source file for basic linked list service. |
| * |
| **************************************************************************/ |
| #include "llist.h" |
| |
| #define LIST_NULL ((void *)0) |
| /*! |
| * add_to_list |
| * |
| * Places new element at the start of the list. |
| * |
| * @param head - list head |
| * @param node - new element to add |
| * |
| */ |
| void add_to_list(struct llist **head, struct llist *node) |
| { |
| if (node == LIST_NULL) |
| { |
| return; |
| } |
| |
| if (*head != LIST_NULL) |
| { |
| /* Place the new element at the start of list. */ |
| node->next = *head; |
| node->prev = LIST_NULL; |
| (*head)->prev = node; |
| *head = node; |
| } |
| else |
| { |
| /* List is empty - assign new element to list head. */ |
| *head = node; |
| (*head)->next = LIST_NULL; |
| (*head)->prev = LIST_NULL; |
| } |
| } |
| |
| /*! |
| * remove_from_list |
| * |
| * Removes the given element from the list. |
| * |
| * @param head - list head |
| * @param element - element to remove from list |
| * |
| */ |
| void remove_from_list(struct llist **head, struct llist *node) |
| { |
| if ((*head == LIST_NULL) || (node == LIST_NULL)) |
| { |
| return; |
| } |
| |
| if (node == *head) |
| { |
| /* First element has to be removed. */ |
| *head = (*head)->next; |
| } |
| else if (node->next == LIST_NULL) |
| { |
| /* Last element has to be removed. */ |
| node->prev->next = node->next; |
| } |
| else |
| { |
| /* Intermediate element has to be removed. */ |
| node->prev->next = node->next; |
| node->next->prev = node->prev; |
| } |
| } |