unit-tests: Add a simple thread_cancel() test
[strongswan.git] / src / libstrongswan / collections / linked_list.h
1 /*
2 * Copyright (C) 2007-2011 Tobias Brunner
3 * Copyright (C) 2005-2008 Martin Willi
4 * Copyright (C) 2005 Jan Hutter
5 * Hochschule fuer Technik Rapperswil
6 *
7 * This program is free software; you can redistribute it and/or modify it
8 * under the terms of the GNU General Public License as published by the
9 * Free Software Foundation; either version 2 of the License, or (at your
10 * option) any later version. See <http://www.fsf.org/copyleft/gpl.txt>.
11 *
12 * This program is distributed in the hope that it will be useful, but
13 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
14 * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
15 * for more details.
16 */
17
18 /**
19 * @defgroup linked_list linked_list
20 * @{ @ingroup collections
21 */
22
23 #ifndef LINKED_LIST_H_
24 #define LINKED_LIST_H_
25
26 typedef struct linked_list_t linked_list_t;
27
28 #include <collections/enumerator.h>
29
30 /**
31 * Method to match elements in a linked list (used in find_* functions)
32 *
33 * @param item current list item
34 * @param ... user supplied data (only pointers, at most 5)
35 * @return
36 * - TRUE, if the item matched
37 * - FALSE, otherwise
38 */
39 typedef bool (*linked_list_match_t)(void *item, ...);
40
41 /**
42 * Method to be invoked on elements in a linked list (used in invoke_* functions)
43 *
44 * @param item current list item
45 * @param ... user supplied data (only pointers, at most 5)
46 */
47 typedef void (*linked_list_invoke_t)(void *item, ...);
48
49 /**
50 * Class implementing a double linked list.
51 *
52 * General purpose linked list. This list is not synchronized.
53 */
54 struct linked_list_t {
55
56 /**
57 * Gets the count of items in the list.
58 *
59 * @return number of items in list
60 */
61 int (*get_count) (linked_list_t *this);
62
63 /**
64 * Create an enumerator over the list.
65 *
66 * @note The enumerator's position is invalid before the first call
67 * to enumerate().
68 *
69 * @return enumerator over list items
70 */
71 enumerator_t* (*create_enumerator)(linked_list_t *this);
72
73 /**
74 * Resets the enumerator's current position to the beginning of the list.
75 *
76 * @param enumerator enumerator to reset
77 */
78 void (*reset_enumerator)(linked_list_t *this, enumerator_t *enumerator);
79
80 /**
81 * Inserts a new item at the beginning of the list.
82 *
83 * @param item item value to insert in list
84 */
85 void (*insert_first) (linked_list_t *this, void *item);
86
87 /**
88 * Removes the first item in the list and returns its value.
89 *
90 * @param item returned value of first item, or NULL
91 * @return SUCCESS, or NOT_FOUND if list is empty
92 */
93 status_t (*remove_first) (linked_list_t *this, void **item);
94
95 /**
96 * Inserts a new item before the item the enumerator currently points to.
97 *
98 * If this method is called before starting the enumeration the item is
99 * inserted first. If it is called after all items have been enumerated
100 * the item is inserted last. This is helpful when inserting items into
101 * a sorted list.
102 *
103 * @note The position of the enumerator is not changed.
104 *
105 * @param enumerator enumerator with position
106 * @param item item value to insert in list
107 */
108 void (*insert_before)(linked_list_t *this, enumerator_t *enumerator,
109 void *item);
110
111 /**
112 * Remove an item from the list where the enumerator points to.
113 *
114 * @param enumerator enumerator with position
115 */
116 void (*remove_at)(linked_list_t *this, enumerator_t *enumerator);
117
118 /**
119 * Remove items from the list matching the given item.
120 *
121 * If a compare function is given, it is called for each item, with the
122 * first parameter being the current list item and the second parameter
123 * being the supplied item. Return TRUE from the compare function to remove
124 * the item, return FALSE to keep it in the list.
125 *
126 * If compare is NULL, comparison is done by pointers.
127 *
128 * @param item item to remove/pass to comparator
129 * @param compare compare function, or NULL
130 * @return number of removed items
131 */
132 int (*remove)(linked_list_t *this, void *item, bool (*compare)(void*,void*));
133
134 /**
135 * Returns the value of the first list item without removing it.
136 *
137 * @param item returned value of first item
138 * @return SUCCESS, NOT_FOUND if list is empty
139 */
140 status_t (*get_first) (linked_list_t *this, void **item);
141
142 /**
143 * Inserts a new item at the end of the list.
144 *
145 * @param item value to insert into list
146 */
147 void (*insert_last) (linked_list_t *this, void *item);
148
149 /**
150 * Removes the last item in the list and returns its value.
151 *
152 * @param item returned value of last item, or NULL
153 * @return SUCCESS, NOT_FOUND if list is empty
154 */
155 status_t (*remove_last) (linked_list_t *this, void **item);
156
157 /**
158 * Returns the value of the last list item without removing it.
159 *
160 * @param item returned value of last item
161 * @return SUCCESS, NOT_FOUND if list is empty
162 */
163 status_t (*get_last) (linked_list_t *this, void **item);
164
165 /**
166 * Find the first matching element in the list.
167 *
168 * The first object passed to the match function is the current list item,
169 * followed by the user supplied data.
170 * If the supplied function returns TRUE this function returns SUCCESS, and
171 * the current object is returned in the third parameter, otherwise,
172 * the next item is checked.
173 *
174 * If match is NULL, *item and the current object are compared.
175 *
176 * @warning Only use pointers as user supplied data.
177 *
178 * @param match comparison function to call on each object, or NULL
179 * @param item the list item, if found
180 * @param ... user data to supply to match function (limited to 5 arguments)
181 * @return SUCCESS if found, NOT_FOUND otherwise
182 */
183 status_t (*find_first) (linked_list_t *this, linked_list_match_t match,
184 void **item, ...);
185
186 /**
187 * Invoke a method on all of the contained objects.
188 *
189 * If a linked list contains objects with function pointers,
190 * invoke() can call a method on each of the objects. The
191 * method is specified by an offset of the function pointer,
192 * which can be evalutated at compile time using the offsetof
193 * macro, e.g.: list->invoke(list, offsetof(object_t, method));
194 *
195 * @warning Only use pointers as user supplied data.
196 *
197 * @param offset offset of the method to invoke on objects
198 * @param ... user data to supply to called function (limited to 5 arguments)
199 */
200 void (*invoke_offset) (linked_list_t *this, size_t offset, ...);
201
202 /**
203 * Invoke a function on all of the contained objects.
204 *
205 * @warning Only use pointers as user supplied data.
206 *
207 * @param function offset of the method to invoke on objects
208 * @param ... user data to supply to called function (limited to 5 arguments)
209 */
210 void (*invoke_function) (linked_list_t *this, linked_list_invoke_t function, ...);
211
212 /**
213 * Clones a list and its objects using the objects' clone method.
214 *
215 * @param offset offset ot the objects clone function
216 * @return cloned list
217 */
218 linked_list_t *(*clone_offset) (linked_list_t *this, size_t offset);
219
220 /**
221 * Destroys a linked_list object.
222 */
223 void (*destroy) (linked_list_t *this);
224
225 /**
226 * Destroys a list and its objects using the destructor.
227 *
228 * If a linked list and the contained objects should be destroyed, use
229 * destroy_offset. The supplied offset specifies the destructor to
230 * call on each object. The offset may be calculated using the offsetof
231 * macro, e.g.: list->destroy_offset(list, offsetof(object_t, destroy));
232 *
233 * @param offset offset of the objects destructor
234 */
235 void (*destroy_offset) (linked_list_t *this, size_t offset);
236
237 /**
238 * Destroys a list and its contents using a a cleanup function.
239 *
240 * If a linked list and its contents should get destroyed using a specific
241 * cleanup function, use destroy_function. This is useful when the
242 * list contains malloc()-ed blocks which should get freed,
243 * e.g.: list->destroy_function(list, free);
244 *
245 * @param function function to call on each object
246 */
247 void (*destroy_function) (linked_list_t *this, void (*)(void*));
248 };
249
250 /**
251 * Creates an empty linked list object.
252 *
253 * @return linked_list_t object.
254 */
255 linked_list_t *linked_list_create(void);
256
257 /**
258 * Creates a linked list from an enumerator.
259 *
260 * @param enumerator enumerator over void*, gets destroyed
261 * @return linked_list_t object, containing enumerated values
262 */
263 linked_list_t *linked_list_create_from_enumerator(enumerator_t *enumerator);
264
265 /**
266 * Creates a linked list from a NULL terminated vararg list of items.
267 *
268 * @param first first item
269 * @param ... subsequent items, terminated by NULL
270 * @return linked_list_t object, containing passed items
271 */
272 linked_list_t *linked_list_create_with_items(void *first, ...);
273
274 #endif /** LINKED_LIST_H_ @}*/