1 /*
2 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
3 *
4 * Copyright 2017 Mike Becker, Olaf Wintermann All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions are met:
8 *
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 *
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
17 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
20 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
21 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
22 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
23 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
24 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
25 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
26 * POSSIBILITY OF SUCH DAMAGE.
27 */
28 /**
29 * Doubly linked list implementation.
30 *
31 * @file list.h
32 * @author Mike Becker
33 * @author Olaf Wintermann
34 */
35
36 #ifndef UCX_LIST_H
37 #define UCX_LIST_H
38
39 #include "ucx.h"
40 #include "allocator.h"
41
42 #ifdef __cplusplus
43 extern "C" {
44 #endif
45
46 /**
47 * Loop statement for UCX lists.
48 *
49 * The first argument is the name of the iteration variable. The scope of
50 * this variable is limited to the <code>UCX_FOREACH</code> statement.
51 *
52 * The second argument is a pointer to the list. In most cases this will be the
53 * pointer to the first element of the list, but it may also be an arbitrary
54 * element of the list. The iteration will then start with that element.
55 *
56 * @param list The first element of the list
57 * @param elem The variable name of the element
58 */
59 #define UCX_FOREACH(elem,list) \
60 for (UcxList* elem = (UcxList*) list ; elem != NULL ; elem = elem->next)
61
62 /**
63 * UCX list type.
64 * @see UcxList
65 */
66 typedef struct UcxList UcxList;
67
68 /**
69 * UCX list structure.
70 */
71 struct UcxList {
72 /**
73 * List element payload.
74 */
75 void *data;
76 /**
77 * Pointer to the next list element or <code>NULL</code>, if this is the
78 * last element.
79 */
80 UcxList *next;
81 /**
82 * Pointer to the previous list element or <code>NULL</code>, if this is
83 * the first element.
84 */
85 UcxList *prev;
86 };
87
88 /**
89 * Creates an element-wise copy of a list.
90 *
91 * This function clones the specified list by creating new list elements and
92 * copying the data with the specified copy_func(). If no copy_func() is
93 * specified, a shallow copy is created and the new list will reference the
94 * same data as the source list.
95 *
96 * @param list the list to copy
97 * @param cpyfnc a pointer to the function that shall copy an element (may be
98 * <code>NULL</code>)
99 * @param data additional data for the copy_func()
100 * @return a pointer to the copy
101 */
102 UcxList *ucx_list_clone(const UcxList *list, copy_func cpyfnc, void* data);
103
104 /**
105 * Creates an element-wise copy of a list using a UcxAllocator.
106 *
107 * See ucx_list_clone() for details.
108 *
109 * You might want to pass the allocator via the <code>data</code> parameter,
110 * to access it within the copy function for making deep copies.
111 *
112 * @param allocator the allocator to use
113 * @param list the list to copy
114 * @param cpyfnc a pointer to the function that shall copy an element (may be
115 * <code>NULL</code>)
116 * @param data additional data for the copy_func()
117 * @return a pointer to the copy
118 * @see ucx_list_clone()
119 */
120 UcxList *ucx_list_clone_a(UcxAllocator *allocator, const UcxList *list,
121 copy_func cpyfnc, void* data);
122
123 /**
124 * Compares two UCX lists element-wise by using a compare function.
125 *
126 * Each element of the two specified lists are compared by using the specified
127 * compare function and the additional data. The type and content of this
128 * additional data depends on the cmp_func() used.
129 *
130 * If the list pointers denote elements within a list, the lists are compared
131 * starting with the denoted elements. Thus any previous elements are not taken
132 * into account. This might be useful to check, if certain list tails match
133 * each other.
134 *
135 * @param list1 the first list
136 * @param list2 the second list
137 * @param cmpfnc the compare function
138 * @param data additional data for the compare function
139 * @return 1, if and only if the two lists equal element-wise, 0 otherwise
140 */
141 int ucx_list_equals(const UcxList *list1, const UcxList *list2,
142 cmp_func cmpfnc, void* data);
143
144 /**
145 * Destroys the entire list.
146 *
147 * The members of the list are not automatically freed, so ensure they are
148 * otherwise referenced or destroyed by ucx_list_free_contents().
149 * Otherwise, a memory leak is likely to occur.
150 *
151 * <b>Caution:</b> the argument <b>MUST</b> denote an entire list (i.e. a call
152 * to ucx_list_first() on the argument must return the argument itself)
153 *
154 * @param list the list to free
155 * @see ucx_list_free_contents()
156 */
157 void ucx_list_free(UcxList *list);
158
159 /**
160 * Destroys the entire list using a UcxAllocator.
161 *
162 * See ucx_list_free() for details.
163 *
164 * @param allocator the allocator to use
165 * @param list the list to free
166 * @see ucx_list_free()
167 */
168 void ucx_list_free_a(UcxAllocator *allocator, UcxList *list);
169
170 /**
171 * Destroys the contents of the specified list by calling the specified
172 * destructor on each of them.
173 *
174 * Note, that the contents are not usable afterwards and the list should be
175 * destroyed with ucx_list_free().
176 *
177 * If no destructor is specified (<code>NULL</code>), stdlib's free() is used.
178 *
179 * @param list the list for which the contents shall be freed
180 * @param destr optional destructor function
181 * @see ucx_list_free()
182 */
183 void ucx_list_free_content(UcxList* list, ucx_destructor destr);
184
185
186 /**
187 * Inserts an element at the end of the list.
188 *
189 * This is generally an O(n) operation, as the end of the list is retrieved with
190 * ucx_list_last().
191 *
192 * @param list the list where to append the data, or <code>NULL</code> to
193 * create a new list
194 * @param data the data to insert
195 * @return <code>list</code>, if it is not <code>NULL</code> or a pointer to
196 * the newly created list otherwise
197 */
198 UcxList *ucx_list_append(UcxList *list, void *data);
199
200 /**
201 * Inserts an element at the end of the list using a UcxAllocator.
202 *
203 * See ucx_list_append() for details.
204 *
205 * @param allocator the allocator to use
206 * @param list the list where to append the data, or <code>NULL</code> to
207 * create a new list
208 * @param data the data to insert
209 * @return <code>list</code>, if it is not <code>NULL</code> or a pointer to
210 * the newly created list otherwise
211 * @see ucx_list_append()
212 */
213 UcxList *ucx_list_append_a(UcxAllocator *allocator, UcxList *list, void *data);
214
215
216 /**
217 * Inserts an element at the beginning of the list.
218 *
219 * You <i>should</i> overwrite the old list pointer by calling
220 * <code>mylist = ucx_list_prepend(mylist, mydata);</code>. However, you may
221 * also perform successive calls of ucx_list_prepend() on the same list pointer,
222 * as this function always searchs for the head of the list with
223 * ucx_list_first().
224 *
225 * @param list the list where to insert the data or <code>NULL</code> to create
226 * a new list
227 * @param data the data to insert
228 * @return a pointer to the new list head
229 */
230 UcxList *ucx_list_prepend(UcxList *list, void *data);
231
232 /**
233 * Inserts an element at the beginning of the list using a UcxAllocator.
234 *
235 * See ucx_list_prepend() for details.
236 *
237 * @param allocator the allocator to use
238 * @param list the list where to insert the data or <code>NULL</code> to create
239 * a new list
240 * @param data the data to insert
241 * @return a pointer to the new list head
242 * @see ucx_list_prepend()
243 */
244 UcxList *ucx_list_prepend_a(UcxAllocator *allocator, UcxList *list, void *data);
245
246 /**
247 * Concatenates two lists.
248 *
249 * Either of the two arguments may be <code>NULL</code>.
250 *
251 * This function modifies the references to the next/previous element of
252 * the last/first element of <code>list1</code>/<code>
253 * list2</code>.
254 *
255 * @param list1 first list
256 * @param list2 second list
257 * @return if <code>list1</code> is <code>NULL</code>, <code>list2</code> is
258 * returned, otherwise <code>list1</code> is returned
259 */
260 UcxList *ucx_list_concat(UcxList *list1, UcxList *list2);
261
262 /**
263 * Returns the first element of a list.
264 *
265 * If the argument is the list pointer, it is directly returned. Otherwise
266 * this function traverses to the first element of the list and returns the
267 * list pointer.
268 *
269 * @param elem one element of the list
270 * @return the first element of the list, the specified element is a member of
271 */
272 UcxList *ucx_list_first(const UcxList *elem);
273
274 /**
275 * Returns the last element of a list.
276 *
277 * If the argument has no successor, it is the last element and therefore
278 * directly returned. Otherwise this function traverses to the last element of
279 * the list and returns it.
280 *
281 * @param elem one element of the list
282 * @return the last element of the list, the specified element is a member of
283 */
284 UcxList *ucx_list_last(const UcxList *elem);
285
286 /**
287 * Returns the list element at the specified index.
288 *
289 * @param list the list to retrieve the element from
290 * @param index index of the element to return
291 * @return the element at the specified index or <code>NULL</code>, if the
292 * index is greater than the list size
293 */
294 UcxList *ucx_list_get(const UcxList *list, size_t index);
295
296 /**
297 * Returns the index of an element.
298 *
299 * @param list the list where to search for the element
300 * @param elem the element to find
301 * @return the index of the element or -1 if the list does not contain the
302 * element
303 */
304 ssize_t ucx_list_indexof(const UcxList *list, const UcxList *elem);
305
306 /**
307 * Returns the element count of the list.
308 *
309 * @param list the list whose elements are counted
310 * @return the element count
311 */
312 size_t ucx_list_size(const UcxList *list);
313
314 /**
315 * Returns the index of an element containing the specified data.
316 *
317 * This function uses a cmp_func() to compare the data of each list element
318 * with the specified data. If no cmp_func is provided, the pointers are
319 * compared.
320 *
321 * If the list contains the data more than once, the index of the first
322 * occurrence is returned.
323 *
324 * @param list the list where to search for the data
325 * @param elem the element data
326 * @param cmpfnc the compare function
327 * @param data additional data for the compare function
328 * @return the index of the element containing the specified data or -1 if the
329 * data is not found in this list
330 */
331 ssize_t ucx_list_find(const UcxList *list, void *elem,
332 cmp_func cmpfnc, void *data);
333
334 /**
335 * Checks, if a list contains a specific element.
336 *
337 * An element is found, if ucx_list_find() returns a value greater than -1.
338 *
339 * @param list the list where to search for the data
340 * @param elem the element data
341 * @param cmpfnc the compare function
342 * @param data additional data for the compare function
343 * @return 1, if and only if the list contains the specified element data
344 * @see ucx_list_find()
345 */
346 int ucx_list_contains(const UcxList *list, void *elem,
347 cmp_func cmpfnc, void *data);
348
349 /**
350 * Sorts a UcxList with natural merge sort.
351 *
352 * This function uses O(n) additional temporary memory for merge operations
353 * that is automatically freed after each merge.
354 *
355 * As the head of the list might change, you <b>MUST</b> call this function
356 * as follows: <code>mylist = ucx_list_sort(mylist, mycmpfnc, mydata);</code>.
357 *
358 * @param list the list to sort
359 * @param cmpfnc the function that shall be used to compare the element data
360 * @param data additional data for the cmp_func()
361 * @return the sorted list
362 */
363 UcxList *ucx_list_sort(UcxList *list, cmp_func cmpfnc, void *data);
364
365 /**
366 * Removes an element from the list.
367 *
368 * If the first element is removed, the list pointer changes. So it is
369 * <i>highly recommended</i> to <i>always</i> update the pointer by calling
370 * <code>mylist = ucx_list_remove(mylist, myelem);</code>.
371 *
372 * @param list the list from which the element shall be removed
373 * @param element the element to remove
374 * @return returns the updated list pointer or <code>NULL</code>, if the list
375 * is now empty
376 */
377 UcxList *ucx_list_remove(UcxList *list, UcxList *element);
378
379 /**
380 * Removes an element from the list using a UcxAllocator.
381 *
382 * See ucx_list_remove() for details.
383 *
384 * @param allocator the allocator to use
385 * @param list the list from which the element shall be removed
386 * @param element the element to remove
387 * @return returns the updated list pointer or <code>NULL</code>, if the list
388 * @see ucx_list_remove()
389 */
390 UcxList *ucx_list_remove_a(UcxAllocator *allocator, UcxList *list,
391 UcxList *element);
392
393 /**
394 * Returns the union of two lists.
395 *
396 * The union is a list of unique elements regarding cmpfnc obtained from
397 * both source lists.
398 *
399 * @param left the left source list
400 * @param right the right source list
401 * @param cmpfnc a function to compare elements
402 * @param cmpdata additional data for the compare function
403 * @param cpfnc a function to copy the elements
404 * @param cpdata additional data for the copy function
405 * @return a new list containing the union
406 */
407 UcxList* ucx_list_union(const UcxList *left, const UcxList *right,
408 cmp_func cmpfnc, void* cmpdata,
409 copy_func cpfnc, void* cpdata);
410
411 /**
412 * Returns the union of two lists.
413 *
414 * The union is a list of unique elements regarding cmpfnc obtained from
415 * both source lists.
416 *
417 * @param allocator allocates the new list elements
418 * @param left the left source list
419 * @param right the right source list
420 * @param cmpfnc a function to compare elements
421 * @param cmpdata additional data for the compare function
422 * @param cpfnc a function to copy the elements
423 * @param cpdata additional data for the copy function
424 * @return a new list containing the union
425 */
426 UcxList* ucx_list_union_a(UcxAllocator *allocator,
427 const UcxList *left, const UcxList *right,
428 cmp_func cmpfnc, void* cmpdata,
429 copy_func cpfnc, void* cpdata);
430
431 /**
432 * Returns the intersection of two lists.
433 *
434 * The intersection contains all elements of the left list
435 * (including duplicates) that can be found in the right list.
436 *
437 * @param left the left source list
438 * @param right the right source list
439 * @param cmpfnc a function to compare elements
440 * @param cmpdata additional data for the compare function
441 * @param cpfnc a function to copy the elements
442 * @param cpdata additional data for the copy function
443 * @return a new list containing the intersection
444 */
445 UcxList* ucx_list_intersection(const UcxList *left, const UcxList *right,
446 cmp_func cmpfnc, void* cmpdata,
447 copy_func cpfnc, void* cpdata);
448
449 /**
450 * Returns the intersection of two lists.
451 *
452 * The intersection contains all elements of the left list
453 * (including duplicates) that can be found in the right list.
454 *
455 * @param allocator allocates the new list elements
456 * @param left the left source list
457 * @param right the right source list
458 * @param cmpfnc a function to compare elements
459 * @param cmpdata additional data for the compare function
460 * @param cpfnc a function to copy the elements
461 * @param cpdata additional data for the copy function
462 * @return a new list containing the intersection
463 */
464 UcxList* ucx_list_intersection_a(UcxAllocator *allocator,
465 const UcxList *left, const UcxList *right,
466 cmp_func cmpfnc, void* cmpdata,
467 copy_func cpfnc, void* cpdata);
468
469 /**
470 * Returns the difference of two lists.
471 *
472 * The difference contains all elements of the left list
473 * (including duplicates) that are not equal to any element of the right list.
474 *
475 * @param left the left source list
476 * @param right the right source list
477 * @param cmpfnc a function to compare elements
478 * @param cmpdata additional data for the compare function
479 * @param cpfnc a function to copy the elements
480 * @param cpdata additional data for the copy function
481 * @return a new list containing the difference
482 */
483 UcxList* ucx_list_difference(const UcxList *left, const UcxList *right,
484 cmp_func cmpfnc, void* cmpdata,
485 copy_func cpfnc, void* cpdata);
486
487 /**
488 * Returns the difference of two lists.
489 *
490 * The difference contains all elements of the left list
491 * (including duplicates) that are not equal to any element of the right list.
492 *
493 * @param allocator allocates the new list elements
494 * @param left the left source list
495 * @param right the right source list
496 * @param cmpfnc a function to compare elements
497 * @param cmpdata additional data for the compare function
498 * @param cpfnc a function to copy the elements
499 * @param cpdata additional data for the copy function
500 * @return a new list containing the difference
501 */
502 UcxList* ucx_list_difference_a(UcxAllocator *allocator,
503 const UcxList *left, const UcxList *right,
504 cmp_func cmpfnc, void* cmpdata,
505 copy_func cpfnc, void* cpdata);
506
507 #ifdef __cplusplus
508 }
509 #endif
510
511 #endif /* UCX_LIST_H */
512
513