1 /* Sequential list data type implemented by an array.
2 Copyright (C) 2006-2023 Free Software Foundation, Inc.
3 Written by Bruno Haible <bruno@clisp.org>, 2006.
4
5 This file is free software: you can redistribute it and/or modify
6 it under the terms of the GNU Lesser General Public License as
7 published by the Free Software Foundation; either version 2.1 of the
8 License, or (at your option) any later version.
9
10 This file is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 GNU Lesser General Public License for more details.
14
15 You should have received a copy of the GNU Lesser General Public License
16 along with this program. If not, see <https://www.gnu.org/licenses/>. */
17
18 #include <config.h>
19
20 /* Specification. */
21 #include "gl_array_list.h"
22
23 #include <stdint.h>
24 #include <stdlib.h>
25 /* Get memcpy. */
26 #include <string.h>
27
28 /* Checked size_t computations. */
29 #include "xsize.h"
30
31 /* -------------------------- gl_list_t Data Type -------------------------- */
32
33 /* Concrete gl_list_impl type, valid for this file only. */
34 struct gl_list_impl
35 {
36 struct gl_list_impl_base base;
37 /* An array of ALLOCATED elements, of which the first COUNT are used.
38 0 <= COUNT <= ALLOCATED. */
39 const void **elements;
40 size_t count;
41 size_t allocated;
42 };
43
44 /* struct gl_list_node_impl doesn't exist here. The pointers are actually
45 indices + 1. */
46 #define INDEX_TO_NODE(index) (gl_list_node_t)(uintptr_t)(size_t)((index) + 1)
47 #define NODE_TO_INDEX(node) ((uintptr_t)(node) - 1)
48
49 static gl_list_t
50 gl_array_nx_create_empty (gl_list_implementation_t implementation,
51 gl_listelement_equals_fn equals_fn,
52 gl_listelement_hashcode_fn hashcode_fn,
53 gl_listelement_dispose_fn dispose_fn,
54 bool allow_duplicates)
55 {
56 struct gl_list_impl *list =
57 (struct gl_list_impl *) malloc (sizeof (struct gl_list_impl));
58
59 if (list == NULL)
60 return NULL;
61
62 list->base.vtable = implementation;
63 list->base.equals_fn = equals_fn;
64 list->base.hashcode_fn = hashcode_fn;
65 list->base.dispose_fn = dispose_fn;
66 list->base.allow_duplicates = allow_duplicates;
67 list->elements = NULL;
68 list->count = 0;
69 list->allocated = 0;
70
71 return list;
72 }
73
74 static gl_list_t
75 gl_array_nx_create (gl_list_implementation_t implementation,
76 gl_listelement_equals_fn equals_fn,
77 gl_listelement_hashcode_fn hashcode_fn,
78 gl_listelement_dispose_fn dispose_fn,
79 bool allow_duplicates,
80 size_t count, const void **contents)
81 {
82 struct gl_list_impl *list =
83 (struct gl_list_impl *) malloc (sizeof (struct gl_list_impl));
84
85 if (list == NULL)
86 return NULL;
87
88 list->base.vtable = implementation;
89 list->base.equals_fn = equals_fn;
90 list->base.hashcode_fn = hashcode_fn;
91 list->base.dispose_fn = dispose_fn;
92 list->base.allow_duplicates = allow_duplicates;
93 if (count > 0)
94 {
95 if (size_overflow_p (xtimes (count, sizeof (const void *))))
96 goto fail;
97 list->elements = (const void **) malloc (count * sizeof (const void *));
98 if (list->elements == NULL)
99 goto fail;
100 memcpy (list->elements, contents, count * sizeof (const void *));
101 }
102 else
103 list->elements = NULL;
104 list->count = count;
105 list->allocated = count;
106
107 return list;
108
109 fail:
110 free (list);
111 return NULL;
112 }
113
114 static size_t _GL_ATTRIBUTE_PURE
115 gl_array_size (gl_list_t list)
116 {
117 return list->count;
118 }
119
120 static const void * _GL_ATTRIBUTE_PURE
121 gl_array_node_value (gl_list_t list, gl_list_node_t node)
122 {
123 uintptr_t index = NODE_TO_INDEX (node);
124 if (!(index < list->count))
125 /* Invalid argument. */
126 abort ();
127 return list->elements[index];
128 }
129
130 static int
131 gl_array_node_nx_set_value (gl_list_t list, gl_list_node_t node,
132 const void *elt)
133 {
134 uintptr_t index = NODE_TO_INDEX (node);
135 if (!(index < list->count))
136 /* Invalid argument. */
137 abort ();
138 list->elements[index] = elt;
139 return 0;
140 }
141
142 static gl_list_node_t _GL_ATTRIBUTE_PURE
143 gl_array_next_node (gl_list_t list, gl_list_node_t node)
144 {
145 uintptr_t index = NODE_TO_INDEX (node);
146 if (!(index < list->count))
147 /* Invalid argument. */
148 abort ();
149 index++;
150 if (index < list->count)
151 return INDEX_TO_NODE (index);
152 else
153 return NULL;
154 }
155
156 static gl_list_node_t _GL_ATTRIBUTE_PURE
157 gl_array_previous_node (gl_list_t list, gl_list_node_t node)
158 {
159 uintptr_t index = NODE_TO_INDEX (node);
160 if (!(index < list->count))
161 /* Invalid argument. */
162 abort ();
163 if (index > 0)
164 return INDEX_TO_NODE (index - 1);
165 else
166 return NULL;
167 }
168
169 static gl_list_node_t _GL_ATTRIBUTE_PURE
170 gl_array_first_node (gl_list_t list)
171 {
172 if (list->count > 0)
173 return INDEX_TO_NODE (0);
174 else
175 return NULL;
176 }
177
178 static gl_list_node_t _GL_ATTRIBUTE_PURE
179 gl_array_last_node (gl_list_t list)
180 {
181 if (list->count > 0)
182 return INDEX_TO_NODE (list->count - 1);
183 else
184 return NULL;
185 }
186
187 static const void * _GL_ATTRIBUTE_PURE
188 gl_array_get_at (gl_list_t list, size_t position)
189 {
190 size_t count = list->count;
191
192 if (!(position < count))
193 /* Invalid argument. */
194 abort ();
195 return list->elements[position];
196 }
197
198 static gl_list_node_t
199 gl_array_nx_set_at (gl_list_t list, size_t position, const void *elt)
200 {
201 size_t count = list->count;
202
203 if (!(position < count))
204 /* Invalid argument. */
205 abort ();
206 list->elements[position] = elt;
207 return INDEX_TO_NODE (position);
208 }
209
210 static size_t _GL_ATTRIBUTE_PURE
211 gl_array_indexof_from_to (gl_list_t list, size_t start_index, size_t end_index,
212 const void *elt)
213 {
214 size_t count = list->count;
215
216 if (!(start_index <= end_index && end_index <= count))
217 /* Invalid arguments. */
218 abort ();
219
220 if (start_index < end_index)
221 {
222 gl_listelement_equals_fn equals = list->base.equals_fn;
223 if (equals != NULL)
224 {
225 size_t i;
226
227 for (i = start_index;;)
228 {
229 if (equals (elt, list->elements[i]))
230 return i;
231 i++;
232 if (i == end_index)
233 break;
234 }
235 }
236 else
237 {
238 size_t i;
239
240 for (i = start_index;;)
241 {
242 if (elt == list->elements[i])
243 return i;
244 i++;
245 if (i == end_index)
246 break;
247 }
248 }
249 }
250 return (size_t)(-1);
251 }
252
253 static gl_list_node_t _GL_ATTRIBUTE_PURE
254 gl_array_search_from_to (gl_list_t list, size_t start_index, size_t end_index,
255 const void *elt)
256 {
257 size_t index = gl_array_indexof_from_to (list, start_index, end_index, elt);
258 return INDEX_TO_NODE (index);
259 }
260
261 /* Ensure that list->allocated > list->count.
262 Return 0 upon success, -1 upon out-of-memory. */
263 static int
264 grow (gl_list_t list)
265 {
266 size_t new_allocated;
267 size_t memory_size;
268 const void **memory;
269
270 new_allocated = xtimes (list->allocated, 2);
271 new_allocated = xsum (new_allocated, 1);
272 memory_size = xtimes (new_allocated, sizeof (const void *));
273 if (size_overflow_p (memory_size))
274 /* Overflow, would lead to out of memory. */
275 return -1;
276 memory = (const void **) realloc (list->elements, memory_size);
277 if (memory == NULL)
278 /* Out of memory. */
279 return -1;
280 list->elements = memory;
281 list->allocated = new_allocated;
282 return 0;
283 }
284
285 static gl_list_node_t
286 gl_array_nx_add_first (gl_list_t list, const void *elt)
287 {
288 size_t count = list->count;
289 const void **elements;
290 size_t i;
291
292 if (count == list->allocated)
293 if (grow (list) < 0)
294 return NULL;
295 elements = list->elements;
296 for (i = count; i > 0; i--)
297 elements[i] = elements[i - 1];
298 elements[0] = elt;
299 list->count = count + 1;
300 return INDEX_TO_NODE (0);
301 }
302
303 static gl_list_node_t
304 gl_array_nx_add_last (gl_list_t list, const void *elt)
305 {
306 size_t count = list->count;
307
308 if (count == list->allocated)
309 if (grow (list) < 0)
310 return NULL;
311 list->elements[count] = elt;
312 list->count = count + 1;
313 return INDEX_TO_NODE (count);
314 }
315
316 static gl_list_node_t
317 gl_array_nx_add_before (gl_list_t list, gl_list_node_t node, const void *elt)
318 {
319 size_t count = list->count;
320 uintptr_t index = NODE_TO_INDEX (node);
321 size_t position;
322 const void **elements;
323 size_t i;
324
325 if (!(index < count))
326 /* Invalid argument. */
327 abort ();
328 position = index;
329 if (count == list->allocated)
330 if (grow (list) < 0)
331 return NULL;
332 elements = list->elements;
333 for (i = count; i > position; i--)
334 elements[i] = elements[i - 1];
335 elements[position] = elt;
336 list->count = count + 1;
337 return INDEX_TO_NODE (position);
338 }
339
340 static gl_list_node_t
341 gl_array_nx_add_after (gl_list_t list, gl_list_node_t node, const void *elt)
342 {
343 size_t count = list->count;
344 uintptr_t index = NODE_TO_INDEX (node);
345 size_t position;
346 const void **elements;
347 size_t i;
348
349 if (!(index < count))
350 /* Invalid argument. */
351 abort ();
352 position = index + 1;
353 if (count == list->allocated)
354 if (grow (list) < 0)
355 return NULL;
356 elements = list->elements;
357 for (i = count; i > position; i--)
358 elements[i] = elements[i - 1];
359 elements[position] = elt;
360 list->count = count + 1;
361 return INDEX_TO_NODE (position);
362 }
363
364 static gl_list_node_t
365 gl_array_nx_add_at (gl_list_t list, size_t position, const void *elt)
366 {
367 size_t count = list->count;
368 const void **elements;
369 size_t i;
370
371 if (!(position <= count))
372 /* Invalid argument. */
373 abort ();
374 if (count == list->allocated)
375 if (grow (list) < 0)
376 return NULL;
377 elements = list->elements;
378 for (i = count; i > position; i--)
379 elements[i] = elements[i - 1];
380 elements[position] = elt;
381 list->count = count + 1;
382 return INDEX_TO_NODE (position);
383 }
384
385 static bool
386 gl_array_remove_node (gl_list_t list, gl_list_node_t node)
387 {
388 size_t count = list->count;
389 uintptr_t index = NODE_TO_INDEX (node);
390 size_t position;
391 const void **elements;
392 size_t i;
393
394 if (!(index < count))
395 /* Invalid argument. */
396 abort ();
397 position = index;
398 elements = list->elements;
399 if (list->base.dispose_fn != NULL)
400 list->base.dispose_fn (elements[position]);
401 for (i = position + 1; i < count; i++)
402 elements[i - 1] = elements[i];
403 list->count = count - 1;
404 return true;
405 }
406
407 static bool
408 gl_array_remove_at (gl_list_t list, size_t position)
409 {
410 size_t count = list->count;
411 const void **elements;
412 size_t i;
413
414 if (!(position < count))
415 /* Invalid argument. */
416 abort ();
417 elements = list->elements;
418 if (list->base.dispose_fn != NULL)
419 list->base.dispose_fn (elements[position]);
420 for (i = position + 1; i < count; i++)
421 elements[i - 1] = elements[i];
422 list->count = count - 1;
423 return true;
424 }
425
426 static bool
427 gl_array_remove (gl_list_t list, const void *elt)
428 {
429 size_t position = gl_array_indexof_from_to (list, 0, list->count, elt);
430 if (position == (size_t)(-1))
431 return false;
432 else
433 return gl_array_remove_at (list, position);
434 }
435
436 static void
437 gl_array_list_free (gl_list_t list)
438 {
439 if (list->elements != NULL)
440 {
441 if (list->base.dispose_fn != NULL)
442 {
443 size_t count = list->count;
444
445 if (count > 0)
446 {
447 gl_listelement_dispose_fn dispose = list->base.dispose_fn;
448 const void **elements = list->elements;
449
450 do
451 dispose (*elements++);
452 while (--count > 0);
453 }
454 }
455 free (list->elements);
456 }
457 free (list);
458 }
459
460 /* --------------------- gl_list_iterator_t Data Type --------------------- */
461
462 static gl_list_iterator_t _GL_ATTRIBUTE_PURE
463 gl_array_iterator (gl_list_t list)
464 {
465 gl_list_iterator_t result;
466
467 result.vtable = list->base.vtable;
468 result.list = list;
469 result.count = list->count;
470 result.p = list->elements + 0;
471 result.q = list->elements + list->count;
472 #if defined GCC_LINT || defined lint
473 result.i = 0;
474 result.j = 0;
475 #endif
476
477 return result;
478 }
479
480 static gl_list_iterator_t _GL_ATTRIBUTE_PURE
481 gl_array_iterator_from_to (gl_list_t list, size_t start_index, size_t end_index)
482 {
483 gl_list_iterator_t result;
484
485 if (!(start_index <= end_index && end_index <= list->count))
486 /* Invalid arguments. */
487 abort ();
488 result.vtable = list->base.vtable;
489 result.list = list;
490 result.count = list->count;
491 result.p = list->elements + start_index;
492 result.q = list->elements + end_index;
493 #if defined GCC_LINT || defined lint
494 result.i = 0;
495 result.j = 0;
496 #endif
497
498 return result;
499 }
500
501 static bool
502 gl_array_iterator_next (gl_list_iterator_t *iterator,
503 const void **eltp, gl_list_node_t *nodep)
504 {
505 gl_list_t list = iterator->list;
506 if (iterator->count != list->count)
507 {
508 if (iterator->count != list->count + 1)
509 /* Concurrent modifications were done on the list. */
510 abort ();
511 /* The last returned element was removed. */
512 iterator->count--;
513 iterator->p = (const void **) iterator->p - 1;
514 iterator->q = (const void **) iterator->q - 1;
515 }
516 if (iterator->p < iterator->q)
517 {
518 const void **p = (const void **) iterator->p;
519 *eltp = *p;
520 if (nodep != NULL)
521 *nodep = INDEX_TO_NODE (p - list->elements);
522 iterator->p = p + 1;
523 return true;
524 }
525 else
526 return false;
527 }
528
529 static void
530 gl_array_iterator_free (_GL_ATTRIBUTE_MAYBE_UNUSED gl_list_iterator_t *iterator)
531 {
532 }
533
534 /* ---------------------- Sorted gl_list_t Data Type ---------------------- */
535
536 static size_t _GL_ATTRIBUTE_PURE
537 gl_array_sortedlist_indexof_from_to (gl_list_t list,
538 gl_listelement_compar_fn compar,
539 size_t low, size_t high,
540 const void *elt)
541 {
542 if (!(low <= high && high <= list->count))
543 /* Invalid arguments. */
544 abort ();
545 if (low < high)
546 {
547 /* At each loop iteration, low < high; for indices < low the values
548 are smaller than ELT; for indices >= high the values are greater
549 than ELT. So, if the element occurs in the list, it is at
550 low <= position < high. */
551 do
552 {
553 size_t mid = low + (high - low) / 2; /* low <= mid < high */
554 int cmp = compar (list->elements[mid], elt);
555
556 if (cmp < 0)
557 low = mid + 1;
558 else if (cmp > 0)
559 high = mid;
560 else /* cmp == 0 */
561 {
562 /* We have an element equal to ELT at index MID. But we need
563 the minimal such index. */
564 high = mid;
565 /* At each loop iteration, low <= high and
566 compar (list->elements[high], elt) == 0,
567 and we know that the first occurrence of the element is at
568 low <= position <= high. */
569 while (low < high)
570 {
571 size_t mid2 = low + (high - low) / 2; /* low <= mid2 < high */
572 int cmp2 = compar (list->elements[mid2], elt);
573
574 if (cmp2 < 0)
575 low = mid2 + 1;
576 else if (cmp2 > 0)
577 /* The list was not sorted. */
578 abort ();
579 else /* cmp2 == 0 */
580 {
581 if (mid2 == low)
582 break;
583 high = mid2 - 1;
584 }
585 }
586 return low;
587 }
588 }
589 while (low < high);
590 /* Here low == high. */
591 }
592 return (size_t)(-1);
593 }
594
595 static size_t _GL_ATTRIBUTE_PURE
596 gl_array_sortedlist_indexof (gl_list_t list, gl_listelement_compar_fn compar,
597 const void *elt)
598 {
599 return gl_array_sortedlist_indexof_from_to (list, compar, 0, list->count,
600 elt);
601 }
602
603 static gl_list_node_t _GL_ATTRIBUTE_PURE
604 gl_array_sortedlist_search_from_to (gl_list_t list,
605 gl_listelement_compar_fn compar,
606 size_t low, size_t high,
607 const void *elt)
608 {
609 size_t index =
610 gl_array_sortedlist_indexof_from_to (list, compar, low, high, elt);
611 return INDEX_TO_NODE (index);
612 }
613
614 static gl_list_node_t _GL_ATTRIBUTE_PURE
615 gl_array_sortedlist_search (gl_list_t list, gl_listelement_compar_fn compar,
616 const void *elt)
617 {
618 size_t index =
619 gl_array_sortedlist_indexof_from_to (list, compar, 0, list->count, elt);
620 return INDEX_TO_NODE (index);
621 }
622
623 static gl_list_node_t
624 gl_array_sortedlist_nx_add (gl_list_t list, gl_listelement_compar_fn compar,
625 const void *elt)
626 {
627 size_t count = list->count;
628 size_t low = 0;
629 size_t high = count;
630
631 /* At each loop iteration, low <= high; for indices < low the values are
632 smaller than ELT; for indices >= high the values are greater than ELT. */
633 while (low < high)
634 {
635 size_t mid = low + (high - low) / 2; /* low <= mid < high */
636 int cmp = compar (list->elements[mid], elt);
637
638 if (cmp < 0)
639 low = mid + 1;
640 else if (cmp > 0)
641 high = mid;
642 else /* cmp == 0 */
643 {
644 low = mid;
645 break;
646 }
647 }
648 return gl_array_nx_add_at (list, low, elt);
649 }
650
651 static bool
652 gl_array_sortedlist_remove (gl_list_t list, gl_listelement_compar_fn compar,
653 const void *elt)
654 {
655 size_t index = gl_array_sortedlist_indexof (list, compar, elt);
656 if (index == (size_t)(-1))
657 return false;
658 else
659 return gl_array_remove_at (list, index);
660 }
661
662
663 const struct gl_list_implementation gl_array_list_implementation =
664 {
665 gl_array_nx_create_empty,
666 gl_array_nx_create,
667 gl_array_size,
668 gl_array_node_value,
669 gl_array_node_nx_set_value,
670 gl_array_next_node,
671 gl_array_previous_node,
672 gl_array_first_node,
673 gl_array_last_node,
674 gl_array_get_at,
675 gl_array_nx_set_at,
676 gl_array_search_from_to,
677 gl_array_indexof_from_to,
678 gl_array_nx_add_first,
679 gl_array_nx_add_last,
680 gl_array_nx_add_before,
681 gl_array_nx_add_after,
682 gl_array_nx_add_at,
683 gl_array_remove_node,
684 gl_array_remove_at,
685 gl_array_remove,
686 gl_array_list_free,
687 gl_array_iterator,
688 gl_array_iterator_from_to,
689 gl_array_iterator_next,
690 gl_array_iterator_free,
691 gl_array_sortedlist_search,
692 gl_array_sortedlist_search_from_to,
693 gl_array_sortedlist_indexof,
694 gl_array_sortedlist_indexof_from_to,
695 gl_array_sortedlist_nx_add,
696 gl_array_sortedlist_remove
697 };