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 /* 39 * linked_list.c 40 * 41 * Created by Matthias Ringwald on 7/13/09. 42 */ 43 44 #include "btstack_linked_list.h" 45 #include <stdlib.h> 46 #include <stdio.h> 47 48 /** 49 * tests if list is empty 50 */ 51 int btstack_linked_list_empty(btstack_linked_list_t * list){ 52 return *list == (void *) 0; 53 } 54 55 /** 56 * btstack_linked_list_get_last_item 57 */ 58 btstack_linked_item_t * btstack_linked_list_get_last_item(btstack_linked_list_t * list){ // <-- find the last item in the list 59 btstack_linked_item_t *lastItem = NULL; 60 btstack_linked_item_t *it; 61 for (it = *list; it ; it = it->next){ 62 if (it) { 63 lastItem = it; 64 } 65 } 66 return lastItem; 67 } 68 69 70 /** 71 * btstack_linked_list_add 72 */ 73 void btstack_linked_list_add(btstack_linked_list_t * list, btstack_linked_item_t *item){ // <-- add item to list 74 // check if already in list 75 btstack_linked_item_t *it; 76 for (it = *list; it ; it = it->next){ 77 if (it == item) { 78 return; 79 } 80 } 81 // add first 82 item->next = *list; 83 *list = item; 84 } 85 86 void btstack_linked_list_add_tail(btstack_linked_list_t * list, btstack_linked_item_t *item){ // <-- add item to list as last element 87 // check if already in list 88 btstack_linked_item_t *it; 89 for (it = (btstack_linked_item_t *) list; it->next ; it = it->next){ 90 if (it->next == item) { 91 return; 92 } 93 } 94 item->next = (btstack_linked_item_t*) 0; 95 it->next = item; 96 } 97 98 /** 99 * Remove data_source from run loop 100 * 101 * @note: assumes that btstack_data_source_t.next is first element in data_source 102 */ 103 int btstack_linked_list_remove(btstack_linked_list_t * list, btstack_linked_item_t *item){ // <-- remove item from list 104 if (!item) return -1; 105 btstack_linked_item_t *it; 106 for (it = (btstack_linked_item_t *) list; it ; it = it->next){ 107 if (it->next == item){ 108 it->next = item->next; 109 return 0; 110 } 111 } 112 return -1; 113 } 114 115 /** 116 * @returns number of items in list 117 */ 118 int btstack_linked_list_count(btstack_linked_list_t * list){ 119 btstack_linked_item_t *it; 120 int counter = 0; 121 for (it = (btstack_linked_item_t *) list; it->next ; it = it->next) { 122 counter++; 123 } 124 return counter; 125 } 126 127 // 128 // Linked List Iterator implementation 129 // 130 131 void btstack_linked_list_iterator_init(btstack_linked_list_iterator_t * it, btstack_linked_list_t * head){ 132 it->advance_on_next = 0; 133 it->prev = (btstack_linked_item_t*) head; 134 it->curr = * head; 135 } 136 137 int btstack_linked_list_iterator_has_next(btstack_linked_list_iterator_t * it){ 138 // 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); 139 if (!it->advance_on_next){ 140 return it->curr != NULL; 141 } 142 if (it->prev->next != it->curr){ 143 // current item has been removed 144 return it->prev->next != NULL; 145 } 146 // current items has not been removed 147 return it->curr->next != NULL; 148 } 149 150 btstack_linked_item_t * btstack_linked_list_iterator_next(btstack_linked_list_iterator_t * it){ 151 if (it->advance_on_next){ 152 if (it->prev->next == it->curr){ 153 it->prev = it->curr; 154 it->curr = it->curr->next; 155 } else { 156 // curr was removed from the list, set it again but don't advance prev 157 it->curr = it->prev->next; 158 } 159 } else { 160 it->advance_on_next = 1; 161 } 162 return it->curr; 163 } 164 165 void btstack_linked_list_iterator_remove(btstack_linked_list_iterator_t * it){ 166 it->curr = it->curr->next; 167 it->prev->next = it->curr; 168 it->advance_on_next = 0; 169 } 170