src/shared/buxtonlist.c

   1 /*
   2  * This file is part of buxton.
   3  *
   4  * Copyright (C) 2014 Intel Corporation
   5  *
   6  * buxton is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU Lesser General Public License as
   8  * published by the Free Software Foundation; either version 2.1
   9  * of the License, or (at your option) any later version.
  10  */
  11
  12 #ifdef HAVE_CONFIG_H
  13         #include "config.h"
  14 #endif
  15
  16 #include <assert.h>
  17 #include <stdbool.h>
  18 #include <stdio.h>
  19 #include <stdlib.h>
  20
  21 #include "buxtonlist.h"
  22
  23 bool buxton_list_append(BuxtonList **list, void *data)
  24 {
  25         BuxtonList *head = *list;
  26
  27         BuxtonList *parent = NULL;
  28         BuxtonList *next = NULL;
  29
  30         if (!head) {
  31                 /* New head generation */
  32                 head = calloc(1, sizeof(BuxtonList));
  33                 if (!head) {
  34                         return false;
  35                 }
  36                 next = parent = head;
  37                 head->size = 0;
  38                 next->tail = NULL;
  39         }
  40
  41         if (!next) {
  42                 next = calloc(1, sizeof(BuxtonList));
  43                 if (!next) {
  44                         return false;
  45                 }
  46                 if (head->tail) {
  47                         parent = head->tail;
  48                 } else {
  49                         parent = head;
  50                 }
  51                 parent->next = next;
  52                 head->tail = next;
  53         }
  54         head->size += 1;
  55         next->data = data;
  56         *list = head;
  57         return true;
  58 }
  59
  60 bool buxton_list_prepend(BuxtonList **list, void *data)
  61 {
  62         BuxtonList *head = *list;
  63         BuxtonList *prev = NULL;
  64
  65         if (!head) {
  66                 /* New head generation */
  67                 head = calloc(1, sizeof(BuxtonList));
  68                 if (!head) {
  69                         return false;
  70                 }
  71                 prev = head;
  72                 head->size = 0;
  73                 prev->tail = head;
  74                 prev->next = NULL;
  75         } else {
  76                 /* New item */
  77                 prev = calloc(1, sizeof(BuxtonList));
  78                 if (!prev) {
  79                         return false;
  80                 }
  81                 prev->size = head->size+1;
  82                 head->size = 0;
  83                 prev->next = head;
  84                 prev->tail = head->tail;
  85                 head->tail = NULL;
  86         }
  87         /* Previous item is now the head */
  88         prev->data = data;
  89         *list = prev;
  90
  91         return true;
  92 }
  93
  94 bool buxton_list_remove(BuxtonList **list, void *data, bool do_free)
  95 {
  96         BuxtonList *head = *list;
  97         BuxtonList *current = head;
  98         BuxtonList *prev = head;
  99
 100         /* Determine the node inside the list */
 101         while ((current != NULL) && (current->data != data)) {
 102                 prev = current;
 103                 current = current->next;
 104         }
 105         /* Not found */
 106         if (!current) {
 107                 return false;
 108         }
 109
 110         /* Data on the head (head removal)*/
 111         if (current == head) {
 112                 if (head->next) {
 113                         head->next->size = head->size -1;
 114                         head->size = 0;
 115                 }
 116                 head = head->next;
 117         } else {
 118                 /* Middle or end */
 119                 prev->next = current->next;
 120                 head->size--;
 121         }
 122
 123         /* Update tail pointer */
 124         if (head && head->tail == current) {
 125                 head->tail = prev;
 126                 head->tail->next = NULL;
 127         }
 128
 129         /* Should free? */
 130         if (do_free) {
 131                 free(current->data);
 132         }
 133         free(current);
 134
 135         *list = head;
 136         return true;
 137 }
 138
 139 /*
 140  * Editor modelines  -  http://www.wireshark.org/tools/modelines.html
 141  *
 142  * Local variables:
 143  * c-basic-offset: 8
 144  * tab-width: 8
 145  * indent-tabs-mode: t
 146  * End:
 147  *
 148  * vi: set shiftwidth=8 tabstop=8 noexpandtab:
 149  * :indentSize=8:tabSize=8:noTabs=false:
 150  */