1 /**
2 * collectd - src/utils_llist.c
3 * Copyright (C) 2006 Florian Forster <octo at verplant.org>
4 *
5 * This program is free software; you can redistribute it and/
6 * or modify it under the terms of the GNU General Public Li-
7 * cence as published by the Free Software Foundation; only
8 * version 2 of the Licence is applicable.
9 *
10 * This program is distributed in the hope that it will be use-
11 * ful, but WITHOUT ANY WARRANTY; without even the implied war-
12 * ranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
13 * See the GNU General Public Licence for more details.
14 *
15 * You should have received a copy of the GNU General Public
16 * Licence along with this program; if not, write to the Free
17 * Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139,
18 * USA.
19 *
20 * Authors:
21 * Florian Forster <octo at verplant.org>
22 */
24 #include "config.h"
26 #include <stdlib.h>
27 #include <string.h>
29 #include "utils_llist.h"
31 /*
32 * Private data types
33 */
34 struct llist_s
35 {
36 llentry_t *head;
37 llentry_t *tail;
38 int size;
39 };
41 /*
42 * Public functions
43 */
44 llist_t *llist_create (void)
45 {
46 llist_t *ret;
48 ret = (llist_t *) malloc (sizeof (llist_t));
49 if (ret == NULL)
50 return (NULL);
52 memset (ret, '\0', sizeof (llist_t));
54 return (ret);
55 }
57 void llist_destroy (llist_t *l)
58 {
59 llentry_t *e_this;
60 llentry_t *e_next;
62 for (e_this = l->head; e_this != NULL; e_this = e_next)
63 {
64 e_next = e_this->next;
65 llentry_destroy (e_this);
66 }
68 free (l);
69 }
71 llentry_t *llentry_create (char *key, void *value)
72 {
73 llentry_t *e;
75 e = (llentry_t *) malloc (sizeof (llentry_t));
76 if (e)
77 {
78 e->key = key;
79 e->value = value;
80 e->next = NULL;
81 }
83 return (e);
84 }
86 void llentry_destroy (llentry_t *e)
87 {
88 free (e);
89 }
91 void llist_append (llist_t *l, llentry_t *e)
92 {
93 e->next = NULL;
95 if (l->tail == NULL)
96 l->head = e;
97 else
98 l->tail->next = e;
100 l->tail = e;
102 ++(l->size);
103 }
105 void llist_prepend (llist_t *l, llentry_t *e)
106 {
107 e->next = l->head;
108 l->head = e;
110 if (l->tail == NULL)
111 l->tail = e;
113 ++(l->size);
114 }
116 void llist_remove (llist_t *l, llentry_t *e)
117 {
118 llentry_t *prev;
120 prev = l->head;
121 while ((prev != NULL) && (prev->next != e))
122 prev = prev->next;
124 if (prev != NULL)
125 prev->next = e->next;
126 if (l->head == e)
127 l->head = e->next;
128 if (l->tail == e)
129 l->tail = prev;
131 --(l->size);
132 }
134 int llist_size (llist_t *l)
135 {
136 return (l ? l->size : 0);
137 }
139 llentry_t *llist_search (llist_t *l, const char *key)
140 {
141 llentry_t *e;
143 for (e = l->head; e != NULL; e = e->next)
144 if (strcmp (key, e->key) == 0)
145 break;
147 return (e);
148 }
150 llentry_t *llist_head (llist_t *l)
151 {
152 return (l->head);
153 }
155 llentry_t *llist_tail (llist_t *l)
156 {
157 return (l->tail);
158 }