Wed, 16 May 2018 14:02:59 +0200
adds remaining documentation for the scstr functions
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 */
36 #ifndef UCX_LIST_H
37 #define UCX_LIST_H
39 #include "ucx.h"
40 #include "allocator.h"
42 #ifdef __cplusplus
43 extern "C" {
44 #endif
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 = list ; elem != NULL ; elem = elem->next)
62 /**
63 * UCX list type.
64 * @see UcxList
65 */
66 typedef struct UcxList UcxList;
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 };
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(UcxList *list, copy_func cpyfnc, void* data);
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, UcxList *list,
121 copy_func cpyfnc, void* data);
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);
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);
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);
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);
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);
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);
215 /**
216 * Inserts an element at the end of the list, if it is not present in the list.
217 *
218 * <b>Note:</b> You should not try to store a freshly allocated object. Since
219 * it might be a duplicate, the memory allocated for that copy would be leaking
220 * afterwards.
221 *
222 * <b>Deprecation notice:</b> This function is considered to do more harm than
223 * it adds usefulness and is going to be removed in a future UCX release.
224 *
225 * @param list the list where to append the data, or <code>NULL</code> to
226 * create a new list
227 * @param data the data to insert
228 * @param cmpfnc the compare function
229 * @param cmpdata additional data for the compare function
230 * @return <code>list</code>, if it is not <code>NULL</code> or a pointer to
231 * the newly created list otherwise
232 * @see ucx_list_append()
233 */
234 UcxList *ucx_list_append_once(UcxList *list, void *data,
235 cmp_func cmpfnc, void *cmpdata);
237 /**
238 * Inserts an element at the end of the list, if it is not present in the list,
239 * using a UcxAllocator.
240 *
241 * <b>Note:</b> You should not try to store a freshly allocated object. Since
242 * it might be a duplicate, the memory allocated for that copy would be leaking
243 * afterwards.
244 *
245 * <b>Deprecation notice:</b> This function is considered to do more harm than
246 * it adds usefulness and is going to be removed in a future UCX release.
247 *
248 * @param allocator the allocator to use
249 * @param list the list where to append the data, or <code>NULL</code> to
250 * create a new list
251 * @param data the data to insert
252 * @param cmpfnc the compare function
253 * @param cmpdata additional data for the compare function
254 * @return <code>list</code>, if it is not <code>NULL</code> or a pointer to
255 * the newly created list otherwise
256 * @see ucx_list_append_a()
257 */
258 UcxList *ucx_list_append_once_a(UcxAllocator *allocator,
259 UcxList *list, void *data, cmp_func cmpfnc, void *cmpdata);
261 /**
262 * Inserts an element at the beginning of the list, if it is not present
263 * in the list.
264 *
265 * <b>Note:</b> You should not try to store a freshly allocated object. Since
266 * it might be a duplicate, the memory allocated for that copy would be leaking
267 * afterwards.
268 *
269 * <b>Deprecation notice:</b> This function is considered to do more harm than
270 * it adds usefulness and is going to be removed in a future UCX release.
271 *
272 * @param list the list where to prepend the data, or <code>NULL</code> to
273 * create a new list
274 * @param data the data to insert
275 * @param cmpfnc the compare function
276 * @param cmpdata additional data for the compare function
277 * @return a pointer to the new list head
278 * @see ucx_list_prepend()
279 */
280 UcxList *ucx_list_prepend_once(UcxList *list, void *data,
281 cmp_func cmpfnc, void *cmpdata);
283 /**
284 * Inserts an element at the beginning of the list, if it is not present in
285 * the list, using a UcxAllocator.
286 *
287 * <b>Note:</b> You should not try to store a freshly allocated object. Since
288 * it might be a duplicate, the memory allocated for that copy would be leaking
289 * afterwards.
290 *
291 * <b>Deprecation notice:</b> This function is considered to do more harm than
292 * it adds usefulness and is going to be removed in a future UCX release.
293 *
294 * @param allocator the allocator to use
295 * @param list the list where to prepend the data, or <code>NULL</code> to
296 * create a new list
297 * @param data the data to insert
298 * @param cmpfnc the compare function
299 * @param cmpdata additional data for the compare function
300 * @return a pointer to the new list head
301 * @see ucx_list_prepend_a()
302 */
303 UcxList *ucx_list_prepend_once_a(UcxAllocator *allocator,
304 UcxList *list, void *data, cmp_func cmpfnc, void *cmpdata);
306 /**
307 * Inserts an element at the beginning of the list.
308 *
309 * You <i>should</i> overwrite the old list pointer by calling
310 * <code>mylist = ucx_list_prepend(mylist, mydata);</code>. However, you may
311 * also perform successive calls of ucx_list_prepend() on the same list pointer,
312 * as this function always searchs for the head of the list with
313 * ucx_list_first().
314 *
315 * @param list the list where to insert the data or <code>NULL</code> to create
316 * a new list
317 * @param data the data to insert
318 * @return a pointer to the new list head
319 */
320 UcxList *ucx_list_prepend(UcxList *list, void *data);
322 /**
323 * Inserts an element at the beginning of the list using a UcxAllocator.
324 *
325 * See ucx_list_prepend() for details.
326 *
327 * @param allocator the allocator to use
328 * @param list the list where to insert the data or <code>NULL</code> to create
329 * a new list
330 * @param data the data to insert
331 * @return a pointer to the new list head
332 * @see ucx_list_prepend()
333 */
334 UcxList *ucx_list_prepend_a(UcxAllocator *allocator, UcxList *list, void *data);
336 /**
337 * Concatenates two lists.
338 *
339 * Either of the two arguments may be <code>NULL</code>.
340 *
341 * This function modifies the references to the next/previous element of
342 * the last/first element of <code>list1</code>/<code>
343 * list2</code>.
344 *
345 * @param list1 first list
346 * @param list2 second list
347 * @return if <code>list1</code> is <code>NULL</code>, <code>list2</code> is
348 * returned, otherwise <code>list1</code> is returned
349 */
350 UcxList *ucx_list_concat(UcxList *list1, UcxList *list2);
352 /**
353 * Returns the first element of a list.
354 *
355 * If the argument is the list pointer, it is directly returned. Otherwise
356 * this function traverses to the first element of the list and returns the
357 * list pointer.
358 *
359 * @param elem one element of the list
360 * @return the first element of the list, the specified element is a member of
361 */
362 UcxList *ucx_list_first(const UcxList *elem);
364 /**
365 * Returns the last element of a list.
366 *
367 * If the argument has no successor, it is the last element and therefore
368 * directly returned. Otherwise this function traverses to the last element of
369 * the list and returns it.
370 *
371 * @param elem one element of the list
372 * @return the last element of the list, the specified element is a member of
373 */
374 UcxList *ucx_list_last(const UcxList *elem);
376 /**
377 * Returns the list element at the specified index.
378 *
379 * @param list the list to retrieve the element from
380 * @param index index of the element to return
381 * @return the element at the specified index or <code>NULL</code>, if the
382 * index is greater than the list size
383 */
384 UcxList *ucx_list_get(const UcxList *list, size_t index);
386 /**
387 * Returns the index of an element.
388 *
389 * @param list the list where to search for the element
390 * @param elem the element to find
391 * @return the index of the element or -1 if the list does not contain the
392 * element
393 */
394 ssize_t ucx_list_indexof(const UcxList *list, const UcxList *elem);
396 /**
397 * Returns the element count of the list.
398 *
399 * @param list the list whose elements are counted
400 * @return the element count
401 */
402 size_t ucx_list_size(const UcxList *list);
404 /**
405 * Returns the index of an element containing the specified data.
406 *
407 * This function uses a cmp_func() to compare the data of each list element
408 * with the specified data. If no cmp_func is provided, the pointers are
409 * compared.
410 *
411 * If the list contains the data more than once, the index of the first
412 * occurrence is returned.
413 *
414 * @param list the list where to search for the data
415 * @param elem the element data
416 * @param cmpfnc the compare function
417 * @param data additional data for the compare function
418 * @return the index of the element containing the specified data or -1 if the
419 * data is not found in this list
420 */
421 ssize_t ucx_list_find(UcxList *list, void *elem, cmp_func cmpfnc, void *data);
423 /**
424 * Checks, if a list contains a specific element.
425 *
426 * An element is found, if ucx_list_find() returns a value greater than -1.
427 *
428 * @param list the list where to search for the data
429 * @param elem the element data
430 * @param cmpfnc the compare function
431 * @param data additional data for the compare function
432 * @return 1, if and only if the list contains the specified element data
433 * @see ucx_list_find()
434 */
435 int ucx_list_contains(UcxList *list, void *elem, cmp_func cmpfnc, void *data);
437 /**
438 * Sorts a UcxList with natural merge sort.
439 *
440 * This function uses O(n) additional temporary memory for merge operations
441 * that is automatically freed after each merge.
442 *
443 * As the head of the list might change, you <b>MUST</b> call this function
444 * as follows: <code>mylist = ucx_list_sort(mylist, mycmpfnc, mydata);</code>.
445 *
446 * @param list the list to sort
447 * @param cmpfnc the function that shall be used to compare the element data
448 * @param data additional data for the cmp_func()
449 * @return the sorted list
450 */
451 UcxList *ucx_list_sort(UcxList *list, cmp_func cmpfnc, void *data);
453 /**
454 * Removes an element from the list.
455 *
456 * If the first element is removed, the list pointer changes. So it is
457 * <i>highly recommended</i> to <i>always</i> update the pointer by calling
458 * <code>mylist = ucx_list_remove(mylist, myelem);</code>.
459 *
460 * @param list the list from which the element shall be removed
461 * @param element the element to remove
462 * @return returns the updated list pointer or <code>NULL</code>, if the list
463 * is now empty
464 */
465 UcxList *ucx_list_remove(UcxList *list, UcxList *element);
467 /**
468 * Removes an element from the list using a UcxAllocator.
469 *
470 * See ucx_list_remove() for details.
471 *
472 * @param allocator the allocator to use
473 * @param list the list from which the element shall be removed
474 * @param element the element to remove
475 * @return returns the updated list pointer or <code>NULL</code>, if the list
476 * @see ucx_list_remove()
477 */
478 UcxList *ucx_list_remove_a(UcxAllocator *allocator, UcxList *list,
479 UcxList *element);
481 #ifdef __cplusplus
482 }
483 #endif
485 #endif /* UCX_LIST_H */