1 /* 2 * Copyright (C) 2014 BlueKitchen GmbH 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. Neither the name of the copyright holders nor the names of 14 * contributors may be used to endorse or promote products derived 15 * from this software without specific prior written permission. 16 * 4. Any redistribution, use, or modification is done solely for 17 * personal benefit and not for any commercial purpose or for 18 * monetary gain. 19 * 20 * THIS SOFTWARE IS PROVIDED BY BLUEKITCHEN GMBH AND CONTRIBUTORS 21 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 22 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 23 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL MATTHIAS 24 * RINGWALD OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 25 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 26 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS 27 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 28 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 29 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF 30 * THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 * 33 * Please inquire about commercial licensing options at 34 * [email protected] 35 * 36 */ 37 38 #define __BTSTACK_FILE__ "btstack_linked_list.c" 39 40 /* 41 * linked_list.c 42 * 43 * Created by Matthias Ringwald on 7/13/09. 44 */ 45 46 #include "btstack_linked_list.h" 47 #include <stdlib.h> 48 #include <stdio.h> 49 50 /** 51 * tests if list is empty 52 */ 53 int btstack_linked_list_empty(btstack_linked_list_t * list){ 54 return *list == (void *) 0; 55 } 56 57 /** 58 * btstack_linked_list_get_last_item 59 */ 60 btstack_linked_item_t * btstack_linked_list_get_last_item(btstack_linked_list_t * list){ // <-- find the last item in the list 61 btstack_linked_item_t *lastItem = NULL; 62 btstack_linked_item_t *it; 63 for (it = *list; it ; it = it->next){ 64 if (it) { 65 lastItem = it; 66 } 67 } 68 return lastItem; 69 } 70 71 72 /** 73 * btstack_linked_list_add 74 */ 75 void btstack_linked_list_add(btstack_linked_list_t * list, btstack_linked_item_t *item){ // <-- add item to list 76 // check if already in list 77 btstack_linked_item_t *it; 78 for (it = *list; it ; it = it->next){ 79 if (it == item) { 80 return; 81 } 82 } 83 // add first 84 item->next = *list; 85 *list = item; 86 } 87 88 void btstack_linked_list_add_tail(btstack_linked_list_t * list, btstack_linked_item_t *item){ // <-- add item to list as last element 89 // check if already in list 90 btstack_linked_item_t *it; 91 for (it = (btstack_linked_item_t *) list; it->next ; it = it->next){ 92 if (it->next == item) { 93 return; 94 } 95 } 96 item->next = (btstack_linked_item_t*) 0; 97 it->next = item; 98 } 99 100 int btstack_linked_list_remove(btstack_linked_list_t * list, btstack_linked_item_t *item){ // <-- remove item from list 101 if (!item) return -1; 102 btstack_linked_item_t *it; 103 for (it = (btstack_linked_item_t *) list; it ; it = it->next){ 104 if (it->next == item){ 105 it->next = item->next; 106 return 0; 107 } 108 } 109 return -1; 110 } 111 112 /** 113 * @returns number of items in list 114 */ 115 int btstack_linked_list_count(btstack_linked_list_t * list){ 116 btstack_linked_item_t *it; 117 int counter = 0; 118 for (it = (btstack_linked_item_t *) list; it->next ; it = it->next) { 119 counter++; 120 } 121 return counter; 122 } 123 124 // get first element 125 btstack_linked_item_t * btstack_linked_list_get_first_item(btstack_linked_list_t * list){ 126 return * list; 127 } 128 129 // pop (get + remove) first element 130 btstack_linked_item_t * btstack_linked_list_pop(btstack_linked_list_t * list){ 131 btstack_linked_item_t * item = *list; 132 if (!item) return NULL; 133 *list = item->next; 134 return item; 135 } 136 137 138 // 139 // Linked List Iterator implementation 140 // 141 142 void btstack_linked_list_iterator_init(btstack_linked_list_iterator_t * it, btstack_linked_list_t * head){ 143 it->advance_on_next = 0; 144 it->prev = (btstack_linked_item_t*) head; 145 it->curr = * head; 146 } 147 148 int btstack_linked_list_iterator_has_next(btstack_linked_list_iterator_t * it){ 149 // log_info("btstack_linked_list_iterator_has_next: advance on next %u, it->prev %p, it->curr %p", it->advance_on_next, it->prev, it->curr); 150 if (!it->advance_on_next){ 151 return it->curr != NULL; 152 } 153 if (it->prev->next != it->curr){ 154 // current item has been removed 155 return it->prev->next != NULL; 156 } 157 // current items has not been removed 158 return it->curr->next != NULL; 159 } 160 161 btstack_linked_item_t * btstack_linked_list_iterator_next(btstack_linked_list_iterator_t * it){ 162 if (it->advance_on_next){ 163 if (it->prev->next == it->curr){ 164 it->prev = it->curr; 165 it->curr = it->curr->next; 166 } else { 167 // curr was removed from the list, set it again but don't advance prev 168 it->curr = it->prev->next; 169 } 170 } else { 171 it->advance_on_next = 1; 172 } 173 return it->curr; 174 } 175 176 void btstack_linked_list_iterator_remove(btstack_linked_list_iterator_t * it){ 177 it->curr = it->curr->next; 178 it->prev->next = it->curr; 179 it->advance_on_next = 0; 180 } 181