Sun, 20 Nov 2022 16:22:16 +0100
#219 improve cx_arl_iter_next
Remove one function call
1 /*
2 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
3 *
4 * Copyright 2021 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 */
29 #include "cx/array_list.h"
30 #include <assert.h>
31 #include <string.h>
32 #include <stdint.h>
34 /* LOW LEVEL ARRAY LIST FUNCTIONS */
36 enum cx_array_copy_result cx_array_copy(
37 void **target,
38 size_t *size,
39 size_t *capacity,
40 size_t index,
41 void const *src,
42 size_t elem_size,
43 size_t elem_count,
44 struct cx_array_reallocator_s *reallocator
45 ) {
46 /* assert pointers */
47 assert(target != NULL);
48 assert(size != NULL);
49 assert(src != NULL);
51 /* determine capacity */
52 size_t cap = capacity == NULL ? *size : *capacity;
54 /* check if resize is required */
55 size_t newsize = index + elem_count;
56 bool needrealloc = newsize > cap;
58 /* reallocate if possible */
59 if (needrealloc) {
60 /* a reallocator and a capacity variable must be available */
61 if (reallocator == NULL || capacity == NULL) {
62 return CX_ARRAY_COPY_REALLOC_NOT_SUPPORTED;
63 }
65 /* check, if we need to repair the src pointer */
66 uintptr_t targetaddr = (uintptr_t) *target;
67 uintptr_t srcaddr = (uintptr_t) src;
68 bool repairsrc = targetaddr <= srcaddr
69 && srcaddr < targetaddr + cap * elem_size;
71 /* increase capacity linearly */
72 cap += 16;
74 /* perform reallocation */
75 void *newmem = reallocator->realloc(
76 *target, cap, elem_size, reallocator
77 );
78 if (newmem == NULL) {
79 return CX_ARRAY_COPY_REALLOC_FAILED;
80 }
82 /* repair src pointer, if necessary */
83 if (repairsrc) {
84 src = ((char *) newmem) + (srcaddr - targetaddr);
85 }
87 /* store new pointer and capacity */
88 *target = newmem;
89 *capacity = cap;
90 }
92 /* determine target pointer */
93 char *start = *target;
94 start += index * elem_size;
96 /* copy elements and set new size */
97 memmove(start, src, elem_count * elem_size);
98 *size = newsize;
100 /* return successfully */
101 return CX_ARRAY_COPY_SUCCESS;
102 }
104 /* HIGH LEVEL ARRAY LIST FUNCTIONS */
106 typedef struct {
107 struct cx_list_s base;
108 void *data;
109 struct cx_array_reallocator_s reallocator;
110 } cx_array_list;
112 static void *cx_arl_realloc(
113 void *array,
114 size_t capacity,
115 size_t elem_size,
116 struct cx_array_reallocator_s *alloc
117 ) {
118 /* retrieve the pointer to the list allocator */
119 CxAllocator const *al = alloc->ptr1;
121 /* use the list allocator to reallocate the memory */
122 return cxRealloc(al, array, capacity * elem_size);
123 }
125 static void cx_arl_destructor(struct cx_list_s *list) {
126 cx_array_list *arl = (cx_array_list *) list;
127 cxFree(list->allocator, arl->data);
128 }
130 static int cx_arl_add(
131 struct cx_list_s *list,
132 void const *elem
133 ) {
134 cx_array_list *arl = (cx_array_list *) list;
135 return cx_array_copy(
136 &arl->data,
137 &list->size,
138 &list->capacity,
139 list->size,
140 elem,
141 list->itemsize,
142 1,
143 &arl->reallocator
144 );
145 }
147 static int cx_arl_insert(
148 struct cx_list_s *list,
149 size_t index,
150 void const *elem
151 ) {
152 if (index > list->size) {
153 return 1;
154 } else if (index == list->size) {
155 return cx_arl_add(list, elem);
156 } else {
157 cx_array_list *arl = (cx_array_list *) list;
159 /* move elements starting at index to the right */
160 if (cx_array_copy(
161 &arl->data,
162 &list->size,
163 &list->capacity,
164 index + 1,
165 ((char *) arl->data) + index * list->itemsize,
166 list->itemsize,
167 list->size - index,
168 &arl->reallocator
169 )) {
170 return 1;
171 }
173 /* place the element */
174 memcpy(((char *) arl->data) + index * list->itemsize,
175 elem, list->itemsize);
177 return 0;
178 }
179 }
181 static int cx_arl_insert_iter(
182 struct cx_iterator_s *iter,
183 void const *elem,
184 int prepend
185 ) {
186 struct cx_list_s *list = iter->src_handle;
187 if (iter->index < list->size) {
188 int result = cx_arl_insert(
189 list,
190 iter->index + 1 - prepend,
191 elem
192 );
193 if (result == 0 && prepend != 0) {
194 iter->index++;
195 iter->elem_handle = ((char *) iter->elem_handle) + list->itemsize;
196 }
197 return result;
198 } else {
199 int result = cx_arl_add(list, elem);
200 iter->index = list->size;
201 return result;
202 }
203 }
205 static int cx_arl_remove(
206 struct cx_list_s *list,
207 size_t index
208 ) {
209 /* out-of-bounds check */
210 if (index >= list->size) {
211 return 1;
212 }
214 cx_array_list *arl = (cx_array_list *) list;
216 /* just move the elements starting at index to the left */
217 int result = cx_array_copy(
218 &arl->data,
219 &list->size,
220 &list->capacity,
221 index,
222 ((char *) arl->data) + (index + 1) * list->itemsize,
223 list->itemsize,
224 list->size - index,
225 &arl->reallocator
226 );
227 if (result == 0) {
228 /* decrease the size */
229 list->size--;
230 }
231 return result;
232 }
234 static void *cx_arl_at(
235 struct cx_list_s const *list,
236 size_t index
237 ) {
238 if (index < list->size) {
239 cx_array_list const *arl = (cx_array_list const *) list;
240 char *space = arl->data;
241 return space + index * list->itemsize;
242 } else {
243 return NULL;
244 }
245 }
247 static size_t cx_arl_find(
248 struct cx_list_s const *list,
249 void const *elem
250 ) {
251 char *cur = ((cx_array_list const *) list)->data;
253 for (size_t i = 0; i < list->size; i++) {
254 if (0 == list->cmpfunc(elem, cur)) {
255 return i;
256 }
257 cur += list->itemsize;
258 }
260 return list->size;
261 }
263 static void cx_arl_sort(struct cx_list_s *list) {
264 qsort(((cx_array_list *) list)->data,
265 list->size,
266 list->itemsize,
267 list->cmpfunc
268 );
269 }
271 static int cx_arl_compare(
272 struct cx_list_s const *list,
273 struct cx_list_s const *other
274 ) {
276 }
278 static void cx_arl_reverse(struct cx_list_s *list) {
280 }
282 static bool cx_arl_iter_valid(struct cx_iterator_s const *iter) {
283 struct cx_list_s const *list = iter->src_handle;
284 return iter->index < list->size;
285 }
287 static void *cx_arl_iter_current(struct cx_iterator_s const *iter) {
288 return iter->elem_handle;
289 }
291 static void cx_arl_iter_next(struct cx_iterator_s *iter) {
292 if (iter->remove) {
293 iter->remove = false;
294 cx_arl_remove(iter->src_handle, iter->index);
295 } else {
296 iter->index++;
297 iter->elem_handle =
298 ((char *) iter->elem_handle)
299 + ((struct cx_list_s const *) iter->src_handle)->itemsize;
300 }
301 }
303 static struct cx_iterator_s cx_arl_iterator(
304 struct cx_list_s *list,
305 size_t index
306 ) {
307 struct cx_iterator_s iter;
309 iter.index = index;
310 iter.src_handle = list;
311 iter.elem_handle = cx_arl_at(list, index);
312 iter.valid = cx_arl_iter_valid;
313 iter.current = cx_arl_iter_current;
314 iter.next = cx_arl_iter_next;
315 iter.remove = false;
317 return iter;
318 }
320 static cx_list_class cx_array_list_class = {
321 cx_arl_destructor,
322 cx_arl_add,
323 cx_arl_insert,
324 cx_arl_insert_iter,
325 cx_arl_remove,
326 cx_arl_at,
327 cx_arl_find,
328 cx_arl_sort,
329 cx_arl_compare,
330 cx_arl_reverse,
331 cx_arl_iterator,
332 };
334 CxList *cxArrayListCreate(
335 CxAllocator const *allocator,
336 CxListComparator comparator,
337 size_t item_size,
338 size_t initial_capacity
339 ) {
340 cx_array_list *list = cxCalloc(allocator, 1, sizeof(cx_array_list));
341 if (list == NULL) return NULL;
343 list->data = cxCalloc(allocator, initial_capacity, item_size);
344 if (list->data == NULL) {
345 cxFree(allocator, list);
346 return NULL;
347 }
349 list->base.cl = &cx_array_list_class;
350 list->base.allocator = allocator;
351 list->base.cmpfunc = comparator;
352 list->base.itemsize = item_size;
353 list->base.capacity = initial_capacity;
355 /* configure the reallocator */
356 list->reallocator.realloc = cx_arl_realloc;
357 list->reallocator.ptr1 = (void *) allocator;
359 return (CxList *) list;
360 }