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 */
28 /**
29 * \file array_list.h
30 * \brief Array list implementation.
31 * \details Also provides several low-level functions for custom array list implementations.
32 * \author Mike Becker
33 * \author Olaf Wintermann
34 * \copyright 2-Clause BSD License
35 */
36
37
38 #ifndef UCX_ARRAY_LIST_H
39 #define UCX_ARRAY_LIST_H
40
41 #include "list.h"
42
43 #ifdef __cplusplus
44 extern "C" {
45 #endif
46
47 /**
48 * The maximum item size in an array list that fits into stack buffer when swapped.
49 */
50 extern unsigned cx_array_swap_sbo_size;
51
52 /**
53 * Declares variables for an array that can be used with the convenience macros.
54 *
55 * @see cx_array_simple_add()
56 * @see cx_array_simple_copy()
57 * @see cx_array_initialize()
58 * @see cx_array_simple_add_sorted()
59 * @see cx_array_simple_insert_sorted()
60 */
61 #define CX_ARRAY_DECLARE(type, name) \
62 type * name; \
63 size_t name##_size; \
64 size_t name##_capacity
65
66 /**
67 * Initializes an array declared with CX_ARRAY_DECLARE().
68 *
69 * The memory for the array is allocated with stdlib malloc().
70 * @param array the array
71 * @param capacity the initial capacity
72 */
73 #define cx_array_initialize(array, capacity) \
74 array##_capacity = capacity; \
75 array##_size = 0; \
76 array = malloc(sizeof(array[0]) * capacity)
77
78 /**
79 * Defines a reallocation mechanism for arrays.
80 */
81 struct cx_array_reallocator_s {
82 /**
83 * Reallocates space for the given array.
84 *
85 * Implementations are not required to free the original array.
86 * This allows reallocation of static memory by allocating heap memory
87 * and copying the array contents. The information in the custom fields of
88 * the referenced allocator can be used to track the state of the memory
89 * or to transport other additional data.
90 *
91 * @param array the array to reallocate
92 * @param capacity the new capacity (number of elements)
93 * @param elem_size the size of each element
94 * @param alloc a reference to this allocator
95 * @return a pointer to the reallocated memory or \c NULL on failure
96 */
97 void *(*realloc)(
98 void *array,
99 size_t capacity,
100 size_t elem_size,
101 struct cx_array_reallocator_s *alloc
102 );
103
104 /**
105 * Custom data pointer.
106 */
107 void *ptr1;
108 /**
109 * Custom data pointer.
110 */
111 void *ptr2;
112 /**
113 * Custom data integer.
114 */
115 size_t int1;
116 /**
117 * Custom data integer.
118 */
119 size_t int2;
120 };
121
122 /**
123 * A default stdlib-based array reallocator.
124 */
125 extern struct cx_array_reallocator_s *cx_array_default_reallocator;
126
127 /**
128 * Return codes for array functions.
129 */
130 enum cx_array_result {
131 CX_ARRAY_SUCCESS,
132 CX_ARRAY_REALLOC_NOT_SUPPORTED,
133 CX_ARRAY_REALLOC_FAILED,
134 };
135
136 /**
137 * Copies elements from one array to another.
138 *
139 * The elements are copied to the \p target array at the specified \p index,
140 * overwriting possible elements. The \p index does not need to be in range of
141 * the current array \p size. If the new index plus the number of elements added
142 * would extend the array's size, and \p capacity is not \c NULL, the remaining
143 * capacity is used.
144 *
145 * If the capacity is insufficient to hold the new data, a reallocation
146 * attempt is made, unless the \p reallocator is set to \c NULL, in which case
147 * this function ultimately returns a failure.
148 *
149 * @param target a pointer to the target array
150 * @param size a pointer to the size of the target array
151 * @param capacity a pointer to the target array's capacity -
152 * \c NULL if only the size shall be used to bound the array (reallocations
153 * will NOT be supported in that case)
154 * @param index the index where the copied elements shall be placed
155 * @param src the source array
156 * @param elem_size the size of one element
157 * @param elem_count the number of elements to copy
158 * @param reallocator the array reallocator to use, or \c NULL
159 * if reallocation shall not happen
160 * @return zero on success, non-zero error code on failure
161 */
162 __attribute__((__nonnull__(1, 2, 5)))
163 enum cx_array_result cx_array_copy(
164 void **target,
165 size_t *size,
166 size_t *capacity,
167 size_t index,
168 const void *src,
169 size_t elem_size,
170 size_t elem_count,
171 struct cx_array_reallocator_s *reallocator
172 );
173
174 /**
175 * Convenience macro that uses cx_array_copy() with a default layout and the default reallocator.
176 *
177 * @param array the name of the array (NOT a pointer to the array)
178 * @param index the index where the copied elements shall be placed
179 * @param src the source array
180 * @param count the number of elements to copy
181 * @see CX_ARRAY_DECLARE()
182 */
183 #define cx_array_simple_copy(array, index, src, count) \
184 cx_array_copy((void**)&(array), &(array##_size), &(array##_capacity), \
185 index, src, sizeof((array)[0]), count, cx_array_default_reallocator)
186
187 /**
188 * Adds an element to an array with the possibility of allocating more space.
189 *
190 * The element \p elem is added to the end of the \p target array which containing
191 * \p size elements, already. The \p capacity must not be \c NULL and point a
192 * variable holding the current maximum number of elements the array can hold.
193 *
194 * If the capacity is insufficient to hold the new element, and the optional
195 * \p reallocator is not \c NULL, an attempt increase the \p capacity is made
196 * and the new capacity is written back.
197 *
198 * @param target a pointer to the target array
199 * @param size a pointer to the size of the target array
200 * @param capacity a pointer to the target array's capacity - must not be \c NULL
201 * @param elem_size the size of one element
202 * @param elem a pointer to the element to add
203 * @param reallocator the array reallocator to use, or \c NULL if reallocation shall not happen
204 * @return zero on success, non-zero error code on failure
205 */
206 #define cx_array_add(target, size, capacity, elem_size, elem, reallocator) \
207 cx_array_copy((void**)(target), size, capacity, *(size), elem, elem_size, 1, reallocator)
208
209 /**
210 * Convenience macro that uses cx_array_add() with a default layout and
211 * the default reallocator.
212 *
213 * @param array the name of the array (NOT a pointer to the array)
214 * @param elem the element to add (NOT a pointer, address is automatically taken)
215 * @see CX_ARRAY_DECLARE()
216 */
217 #define cx_array_simple_add(array, elem) \
218 cx_array_simple_copy(array, array##_size, &(elem), 1)
219
220
221 /**
222 * Inserts a sorted array into another sorted array.
223 *
224 * If either the target or the source array is not already sorted with respect
225 * to the specified \p cmp_func, the behavior is undefined.
226 *
227 * If the capacity is insufficient to hold the new data, a reallocation
228 * attempt is made.
229 *
230 * @param target a pointer to the target array
231 * @param size a pointer to the size of the target array
232 * @param capacity a pointer to the target array's capacity
233 * @param cmp_func the compare function for the elements
234 * @param src the source array
235 * @param elem_size the size of one element
236 * @param elem_count the number of elements to insert
237 * @param reallocator the array reallocator to use
238 * @return zero on success, non-zero error code on failure
239 */
240 __attribute__((__nonnull__))
241 enum cx_array_result cx_array_insert_sorted(
242 void **target,
243 size_t *size,
244 size_t *capacity,
245 cx_compare_func cmp_func,
246 const void *src,
247 size_t elem_size,
248 size_t elem_count,
249 struct cx_array_reallocator_s *reallocator
250 );
251
252 /**
253 * Inserts an element into a sorted array.
254 *
255 * If the target array is not already sorted with respect
256 * to the specified \p cmp_func, the behavior is undefined.
257 *
258 * If the capacity is insufficient to hold the new data, a reallocation
259 * attempt is made.
260 *
261 * @param target a pointer to the target array
262 * @param size a pointer to the size of the target array
263 * @param capacity a pointer to the target array's capacity
264 * @param elem_size the size of one element
265 * @param elem a pointer to the element to add
266 * @param reallocator the array reallocator to use
267 * @return zero on success, non-zero error code on failure
268 */
269 #define cx_array_add_sorted(target, size, capacity, elem_size, elem, cmp_func, reallocator) \
270 cx_array_insert_sorted((void**)(target), size, capacity, cmp_func, elem, elem_size, 1, reallocator)
271
272 /**
273 * Convenience macro for cx_array_add_sorted() with a default
274 * layout and the default reallocator.
275 *
276 * @param array the name of the array (NOT a pointer to the array)
277 * @param elem the element to add (NOT a pointer, address is automatically taken)
278 * @param cmp_func the compare function for the elements
279 * @see CX_ARRAY_DECLARE()
280 */
281 #define cx_array_simple_add_sorted(array, elem, cmp_func) \
282 cx_array_add_sorted(&array, &(array##_size), &(array##_capacity), \
283 sizeof((array)[0]), &(elem), cmp_func, cx_array_default_reallocator)
284
285 /**
286 * Convenience macro for cx_array_insert_sorted() with a default
287 * layout and the default reallocator.
288 *
289 * @param array the name of the array (NOT a pointer to the array)
290 * @param src pointer to the source array
291 * @param n number of elements in the source array
292 * @param cmp_func the compare function for the elements
293 * @see CX_ARRAY_DECLARE()
294 */
295 #define cx_array_simple_insert_sorted(array, src, n, cmp_func) \
296 cx_array_insert_sorted((void**)(&array), &(array##_size), &(array##_capacity), \
297 cmp_func, src, sizeof((array)[0]), n, cx_array_default_reallocator)
298
299
300 /**
301 * Searches the largest lower bound in a sorted array.
302 *
303 * In other words, this function returns the index of the largest element
304 * in \p arr that is less or equal to \p elem with respect to \p cmp_func.
305 * When no such element exists, \p size is returned.
306 *
307 * If \p elem is contained in the array, this is identical to
308 * #cx_array_binary_search().
309 *
310 * If the array is not sorted with respect to the \p cmp_func, the behavior
311 * is undefined.
312 *
313 * @param arr the array to search
314 * @param size the size of the array
315 * @param elem_size the size of one element
316 * @param elem the element to find
317 * @param cmp_func the compare function
318 * @return the index of the largest lower bound, or \p size
319 */
320 __attribute__((__nonnull__))
321 size_t cx_array_binary_search_inf(
322 const void *arr,
323 size_t size,
324 size_t elem_size,
325 const void *elem,
326 cx_compare_func cmp_func
327 );
328
329 /**
330 * Searches an item in a sorted array.
331 *
332 * If the array is not sorted with respect to the \p cmp_func, the behavior
333 * is undefined.
334 *
335 * @param arr the array to search
336 * @param size the size of the array
337 * @param elem_size the size of one element
338 * @param elem the element to find
339 * @param cmp_func the compare function
340 * @return the index of the element in the array, or \p size if the element
341 * cannot be found
342 */
343 __attribute__((__nonnull__))
344 static inline size_t cx_array_binary_search(
345 const void *arr,
346 size_t size,
347 size_t elem_size,
348 const void *elem,
349 cx_compare_func cmp_func
350 ) {
351 size_t index = cx_array_binary_search_inf(
352 arr, size, elem_size, elem, cmp_func
353 );
354 if (index < size && cmp_func(((const char *) arr) + index * elem_size, elem) == 0) {
355 return index;
356 } else {
357 return size;
358 }
359 }
360
361 /**
362 * Searches the smallest upper bound in a sorted array.
363 *
364 * In other words, this function returns the index of the smallest element
365 * in \p arr that is greater or equal to \p elem with respect to \p cmp_func.
366 * When no such element exists, \p size is returned.
367 *
368 * If \p elem is contained in the array, this is identical to
369 * #cx_array_binary_search().
370 *
371 * If the array is not sorted with respect to the \p cmp_func, the behavior
372 * is undefined.
373 *
374 * @param arr the array to search
375 * @param size the size of the array
376 * @param elem_size the size of one element
377 * @param elem the element to find
378 * @param cmp_func the compare function
379 * @return the index of the smallest upper bound, or \p size
380 */
381 __attribute__((__nonnull__))
382 static inline size_t cx_array_binary_search_sup(
383 const void *arr,
384 size_t size,
385 size_t elem_size,
386 const void *elem,
387 cx_compare_func cmp_func
388 ) {
389 size_t inf = cx_array_binary_search_inf(arr, size, elem_size, elem, cmp_func);
390 if (inf == size) {
391 // no infimum means, first element is supremum
392 return 0;
393 } else if (cmp_func(((const char *) arr) + inf * elem_size, elem) == 0) {
394 return inf;
395 } else {
396 return inf + 1;
397 }
398 }
399
400 /**
401 * Swaps two array elements.
402 *
403 * @param arr the array
404 * @param elem_size the element size
405 * @param idx1 index of first element
406 * @param idx2 index of second element
407 */
408 __attribute__((__nonnull__))
409 void cx_array_swap(
410 void *arr,
411 size_t elem_size,
412 size_t idx1,
413 size_t idx2
414 );
415
416 /**
417 * Allocates an array list for storing elements with \p elem_size bytes each.
418 *
419 * If \p elem_size is CX_STORE_POINTERS, the created list will be created as if
420 * cxListStorePointers() was called immediately after creation and the compare
421 * function will be automatically set to cx_cmp_ptr(), if none is given.
422 *
423 * @param allocator the allocator for allocating the list memory
424 * (if \c NULL the cxDefaultAllocator will be used)
425 * @param comparator the comparator for the elements
426 * (if \c NULL, and the list is not storing pointers, sort and find
427 * functions will not work)
428 * @param elem_size the size of each element in bytes
429 * @param initial_capacity the initial number of elements the array can store
430 * @return the created list
431 */
432 CxList *cxArrayListCreate(
433 const CxAllocator *allocator,
434 cx_compare_func comparator,
435 size_t elem_size,
436 size_t initial_capacity
437 );
438
439 /**
440 * Allocates an array list for storing elements with \p elem_size bytes each.
441 *
442 * The list will use the cxDefaultAllocator and \em NO compare function.
443 * If you want to call functions that need a compare function, you have to
444 * set it immediately after creation or use cxArrayListCreate().
445 *
446 * If \p elem_size is CX_STORE_POINTERS, the created list will be created as if
447 * cxListStorePointers() was called immediately after creation and the compare
448 * function will be automatically set to cx_cmp_ptr().
449 *
450 * @param elem_size the size of each element in bytes
451 * @param initial_capacity the initial number of elements the array can store
452 * @return the created list
453 */
454 #define cxArrayListCreateSimple(elem_size, initial_capacity) \
455 cxArrayListCreate(NULL, NULL, elem_size, initial_capacity)
456
457 #ifdef __cplusplus
458 } // extern "C"
459 #endif
460
461 #endif // UCX_ARRAY_LIST_H
462