4265286bdaf899dcb2bba34e97a712876d5455b0
1 /**
2 * collectd - src/utils_llist.c
3 * Copyright (C) 2006 Florian Forster <octo at collectd.org>
4 *
5 * Permission is hereby granted, free of charge, to any person obtaining a
6 * copy of this software and associated documentation files (the "Software"),
7 * to deal in the Software without restriction, including without limitation
8 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
9 * and/or sell copies of the Software, and to permit persons to whom the
10 * Software is furnished to do so, subject to the following conditions:
11 *
12 * The above copyright notice and this permission notice shall be included in
13 * all copies or substantial portions of the Software.
14 *
15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
18 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
20 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
21 * DEALINGS IN THE SOFTWARE.
22 *
23 * Authors:
24 * Florian Forster <octo at collectd.org>
25 */
27 #include "config.h"
29 #include <stdlib.h>
30 #include <string.h>
32 #include "utils_llist.h"
34 /*
35 * Private data types
36 */
37 struct llist_s
38 {
39 llentry_t *head;
40 llentry_t *tail;
41 int size;
42 };
44 /*
45 * Public functions
46 */
47 llist_t *llist_create (void)
48 {
49 llist_t *ret;
51 ret = (llist_t *) malloc (sizeof (llist_t));
52 if (ret == NULL)
53 return (NULL);
55 memset (ret, '\0', sizeof (llist_t));
57 return (ret);
58 }
60 void llist_destroy (llist_t *l)
61 {
62 llentry_t *e_this;
63 llentry_t *e_next;
65 if (l == NULL)
66 return;
68 for (e_this = l->head; e_this != NULL; e_this = e_next)
69 {
70 e_next = e_this->next;
71 llentry_destroy (e_this);
72 }
74 free (l);
75 }
77 llentry_t *llentry_create (char *key, void *value)
78 {
79 llentry_t *e;
81 e = (llentry_t *) malloc (sizeof (llentry_t));
82 if (e)
83 {
84 e->key = key;
85 e->value = value;
86 e->next = NULL;
87 }
89 return (e);
90 }
92 void llentry_destroy (llentry_t *e)
93 {
94 free (e);
95 }
97 void llist_append (llist_t *l, llentry_t *e)
98 {
99 e->next = NULL;
101 if (l->tail == NULL)
102 l->head = e;
103 else
104 l->tail->next = e;
106 l->tail = e;
108 ++(l->size);
109 }
111 void llist_prepend (llist_t *l, llentry_t *e)
112 {
113 e->next = l->head;
114 l->head = e;
116 if (l->tail == NULL)
117 l->tail = e;
119 ++(l->size);
120 }
122 void llist_remove (llist_t *l, llentry_t *e)
123 {
124 llentry_t *prev;
126 if ((l == NULL) || (e == NULL))
127 return;
129 prev = l->head;
130 while ((prev != NULL) && (prev->next != e))
131 prev = prev->next;
133 if (prev != NULL)
134 prev->next = e->next;
135 if (l->head == e)
136 l->head = e->next;
137 if (l->tail == e)
138 l->tail = prev;
140 --(l->size);
141 }
143 int llist_size (llist_t *l)
144 {
145 return (l ? l->size : 0);
146 }
148 static int llist_strcmp (llentry_t *e, void *ud)
149 {
150 if ((e == NULL) || (ud == NULL))
151 return (-1);
152 return (strcmp (e->key, (const char *)ud));
153 }
155 llentry_t *llist_search (llist_t *l, const char *key)
156 {
157 return (llist_search_custom (l, llist_strcmp, (void *)key));
158 }
160 llentry_t *llist_search_custom (llist_t *l,
161 int (*compare) (llentry_t *, void *), void *user_data)
162 {
163 llentry_t *e;
165 if (l == NULL)
166 return (NULL);
168 e = l->head;
169 while (e != NULL) {
170 llentry_t *next = e->next;
172 if (compare (e, user_data) == 0)
173 break;
175 e = next;
176 }
178 return (e);
179 }
181 llentry_t *llist_head (llist_t *l)
182 {
183 if (l == NULL)
184 return (NULL);
185 return (l->head);
186 }
188 llentry_t *llist_tail (llist_t *l)
189 {
190 if (l == NULL)
191 return (NULL);
192 return (l->tail);
193 }