libjaylink/list.c

   1 /*
   2  * This file is part of the libjaylink project.
   3  *
   4  * Copyright (C) 2014-2016 Marc Schink <jaylink-dev@marcschink.de>
   5  *
   6  * This program is free software: you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation, either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  18  */
  19
  20 #include <stdlib.h>
  21
  22 #include "libjaylink-internal.h"
  23
  24 /**
  25  * @file
  26  *
  27  * Singly-linked list functions.
  28  */
  29
  30 /** @private */
  31 JAYLINK_PRIV struct list *list_prepend(struct list *list, void *data)
  32 {
  33         struct list *item;
  34
  35         item = malloc(sizeof(struct list));
  36
  37         if (!item)
  38                 return NULL;
  39
  40         item->data = data;
  41         item->next = list;
  42
  43         return item;
  44 }
  45
  46 /** @private */
  47 JAYLINK_PRIV struct list *list_remove(struct list *list, const void *data)
  48 {
  49         struct list *item;
  50         struct list *tmp;
  51
  52         if (!list)
  53                 return NULL;
  54
  55         item = list;
  56
  57         if (item->data == data) {
  58                 tmp = item->next;
  59                 free(item);
  60                 return tmp;
  61         }
  62
  63         while (item->next) {
  64                 if (item->next->data == data) {
  65                         tmp = item->next;
  66                         item->next = item->next->next;
  67                         free(tmp);
  68                         break;
  69                 }
  70
  71                 item = item->next;
  72         }
  73
  74         return list;
  75 }
  76
  77 /** @private */
  78 JAYLINK_PRIV struct list *list_find_custom(struct list *list,
  79                 list_compare_callback callback, const void *user_data)
  80 {
  81         if (!callback)
  82                 return NULL;
  83
  84         while (list) {
  85                 if (callback(list->data, user_data))
  86                         return list;
  87
  88                 list = list->next;
  89         }
  90
  91         return NULL;
  92 }
  93
  94 /** @private */
  95 JAYLINK_PRIV size_t list_length(struct list *list)
  96 {
  97         size_t length;
  98
  99         for (length = 0; list; length++)
 100                 list = list->next;
 101
 102         return length;
 103 }
 104
 105 /** @private */
 106 JAYLINK_PRIV void list_free(struct list *list)
 107 {
 108         struct list *tmp;
 109
 110         while (list) {
 111                 tmp = list;
 112                 list = list->next;
 113                 free(tmp);
 114         }
 115 }