2 * libudev - interface to udev device information
4 * Copyright (C) 2008 Kay Sievers <kay.sievers@vrfy.org>
6 * This library is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public
8 * License as published by the Free Software Foundation; either
9 * version 2.1 of the License, or (at your option) any later version.
20 #include "libudev-private.h"
25 * One entry in a list, containing a name and an optional value.
27 struct udev_list_entry {
28 struct udev_list_node node;
30 struct udev_list_node *list;
36 /* list head point to itself if empty */
37 void udev_list_init(struct udev_list_node *list)
43 int udev_list_is_empty(struct udev_list_node *list)
45 return list->next == list;
48 static void udev_list_node_insert_between(struct udev_list_node *new,
49 struct udev_list_node *prev,
50 struct udev_list_node *next)
58 void udev_list_node_append(struct udev_list_node *new, struct udev_list_node *list)
60 udev_list_node_insert_between(new, list->prev, list);
63 void udev_list_node_remove(struct udev_list_node *entry)
65 struct udev_list_node *prev = entry->prev;
66 struct udev_list_node *next = entry->next;
75 /* return list entry which embeds this node */
76 static struct udev_list_entry *list_node_to_entry(struct udev_list_node *node)
81 list -= offsetof(struct udev_list_entry, node);
82 return (struct udev_list_entry *)list;
85 /* insert entry into a list as the last element */
86 void udev_list_entry_append(struct udev_list_entry *new, struct udev_list_node *list)
88 /* inserting before the list head make the node the last node in the list */
89 udev_list_node_insert_between(&new->node, list->prev, list);
93 /* remove entry from a list */
94 void udev_list_entry_remove(struct udev_list_entry *entry)
96 udev_list_node_remove(&entry->node);
100 /* insert entry into a list, before a given existing entry */
101 void udev_list_entry_insert_before(struct udev_list_entry *new, struct udev_list_entry *entry)
103 udev_list_node_insert_between(&new->node, entry->node.prev, &entry->node);
104 new->list = entry->list;
107 struct udev_list_entry *udev_list_entry_add(struct udev *udev, struct udev_list_node *list,
108 const char *name, const char *value,
109 int unique, int sort)
111 struct udev_list_entry *entry_loop = NULL;
112 struct udev_list_entry *entry_new;
115 udev_list_entry_foreach(entry_loop, udev_list_get_entry(list)) {
116 if (strcmp(entry_loop->name, name) == 0) {
117 dbg(udev, "'%s' is already in the list\n", name);
118 free(entry_loop->value);
120 entry_loop->value = NULL;
121 dbg(udev, "'%s' value unset\n", name);
124 entry_loop->value = strdup(value);
125 if (entry_loop->value == NULL)
127 dbg(udev, "'%s' value replaced with '%s'\n", name, value);
133 udev_list_entry_foreach(entry_loop, udev_list_get_entry(list)) {
134 if (strcmp(entry_loop->name, name) > 0)
138 entry_new = malloc(sizeof(struct udev_list_entry));
139 if (entry_new == NULL)
141 memset(entry_new, 0x00, sizeof(struct udev_list_entry));
142 entry_new->udev = udev;
143 entry_new->name = strdup(name);
144 if (entry_new->name == NULL) {
149 entry_new->value = strdup(value);
150 if (entry_new->value == NULL) {
151 free(entry_new->name);
156 if (entry_loop != NULL)
157 udev_list_entry_insert_before(entry_new, entry_loop);
159 udev_list_entry_append(entry_new, list);
160 dbg(udev, "'%s=%s' added\n", entry_new->name, entry_new->value);
164 void udev_list_entry_delete(struct udev_list_entry *entry)
166 udev_list_node_remove(&entry->node);
172 void udev_list_cleanup_entries(struct udev *udev, struct udev_list_node *list)
174 struct udev_list_entry *entry_loop;
175 struct udev_list_entry *entry_tmp;
177 udev_list_entry_foreach_safe(entry_loop, entry_tmp, udev_list_get_entry(list))
178 udev_list_entry_delete(entry_loop);
181 struct udev_list_entry *udev_list_get_entry(struct udev_list_node *list)
183 if (udev_list_is_empty(list))
185 return list_node_to_entry(list->next);
189 * udev_list_entry_get_next:
190 * @list_entry: current entry
192 * Returns: the next entry from the list, #NULL is no more entries are found.
194 struct udev_list_entry *udev_list_entry_get_next(struct udev_list_entry *list_entry)
196 struct udev_list_node *next;
198 if (list_entry == NULL)
200 next = list_entry->node.next;
201 /* empty list or no more entries */
202 if (next == list_entry->list)
204 return list_node_to_entry(next);
208 * udev_list_entry_get_by_name:
209 * @list_entry: current entry
210 * @name: name string to match
212 * Returns: the entry where @name matched, #NULL if no matching entry is found.
214 struct udev_list_entry *udev_list_entry_get_by_name(struct udev_list_entry *list_entry, const char *name)
216 struct udev_list_entry *entry;
218 udev_list_entry_foreach(entry, list_entry) {
219 if (strcmp(udev_list_entry_get_name(entry), name) == 0) {
220 dbg(entry->udev, "found '%s=%s'\n", entry->name, entry->value);
228 * udev_list_entry_get_name:
229 * @list_entry: current entry
231 * Returns: the name string of this entry.
233 const char *udev_list_entry_get_name(struct udev_list_entry *list_entry)
235 if (list_entry == NULL)
237 return list_entry->name;
241 * udev_list_entry_get_value:
242 * @list_entry: current entry
244 * Returns: the value string of this entry.
246 const char *udev_list_entry_get_value(struct udev_list_entry *list_entry)
248 if (list_entry == NULL)
250 return list_entry->value;
253 int udev_list_entry_get_flag(struct udev_list_entry *list_entry)
255 if (list_entry == NULL)
257 return list_entry->flag;
260 void udev_list_entry_set_flag(struct udev_list_entry *list_entry, int flag)
262 if (list_entry == NULL)
264 list_entry->flag = flag;