ucx: src/array_list.c@4738a9065907

     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>

    33 // LOW LEVEL ARRAY LIST FUNCTIONS

    35 enum cx_array_copy_result cx_array_copy(

    36         void **target,

    37         size_t *size,

    38         size_t *capacity,

    39         size_t index,

    40         void const *src,

    41         size_t elem_size,

    42         size_t elem_count,

    43         struct cx_array_reallocator_s *reallocator

    44 ) {

    45     // assert pointers

    46     assert(target != NULL);

    47     assert(size != NULL);

    48     assert(src != NULL);

    50     // determine capacity

    51     size_t cap = capacity == NULL ? *size : *capacity;

    53     // check if resize is required

    54     size_t minsize = index + elem_count;

    55     size_t newsize = *size < minsize ? minsize : *size;

    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         // calculate new capacity (next number divisible by 16)

    72         cap = newsize - (newsize % 16) + 16;

    73         assert(cap > newsize);

    75         // perform reallocation

    76         void *newmem = reallocator->realloc(

    77                 *target, cap, elem_size, reallocator

    78         );

    79         if (newmem == NULL) {

    80             return CX_ARRAY_COPY_REALLOC_FAILED;

    81         }

    83         // repair src pointer, if necessary

    84         if (repairsrc) {

    85             src = ((char *) newmem) + (srcaddr - targetaddr);

    86         }

    88         // store new pointer and capacity

    89         *target = newmem;

    90         *capacity = cap;

    91     }

    93     // determine target pointer

    94     char *start = *target;

    95     start += index * elem_size;

    97     // copy elements and set new size

    98     memmove(start, src, elem_count * elem_size);

    99     *size = newsize;

   101     // return successfully

   102     return CX_ARRAY_COPY_SUCCESS;

   103 }

   105 #ifndef CX_ARRAY_SWAP_SBO_SIZE

   106 #define CX_ARRAY_SWAP_SBO_SIZE 512

   107 #endif

   109 void cx_array_swap(

   110         void *arr,

   111         size_t elem_size,

   112         size_t idx1,

   113         size_t idx2

   114 ) {

   115     assert(arr != NULL);

   117     // short circuit

   118     if (idx1 == idx2) return;

   120     char sbo_mem[CX_ARRAY_SWAP_SBO_SIZE];

   121     void *tmp;

   123     // decide if we can use the local buffer

   124     if (elem_size > CX_ARRAY_SWAP_SBO_SIZE) {

   125         tmp = malloc(elem_size);

   126         // we don't want to enforce error handling

   127         if (tmp == NULL) abort();

   128     } else {

   129         tmp = sbo_mem;

   130     }

   132     // calculate memory locations

   133     char *left = arr, *right = arr;

   134     left += idx1 * elem_size;

   135     right += idx2 * elem_size;

   137     // three-way swap

   138     memcpy(tmp, left, elem_size);

   139     memcpy(left, right, elem_size);

   140     memcpy(right, tmp, elem_size);

   142     // free dynamic memory, if it was needed

   143     if (tmp != sbo_mem) {

   144         free(tmp);

   145     }

   146 }

   148 // HIGH LEVEL ARRAY LIST FUNCTIONS

   150 typedef struct {

   151     struct cx_list_s base;

   152     void *data;

   153     struct cx_array_reallocator_s reallocator;

   154 } cx_array_list;

   156 static void *cx_arl_realloc(

   157         void *array,

   158         size_t capacity,

   159         size_t elem_size,

   160         struct cx_array_reallocator_s *alloc

   161 ) {

   162     // retrieve the pointer to the list allocator

   163     CxAllocator const *al = alloc->ptr1;

   165     // use the list allocator to reallocate the memory

   166     return cxRealloc(al, array, capacity * elem_size);

   167 }

   169 static void cx_arl_destructor(struct cx_list_s *list) {

   170     cx_array_list *arl = (cx_array_list *) list;

   171     cxFree(list->allocator, arl->data);

   172 }

   174 static size_t cx_arl_insert_array(

   175         struct cx_list_s *list,

   176         size_t index,

   177         void const *array,

   178         size_t n

   179 ) {

   180     // out of bounds and special case check

   181     if (index > list->size || n == 0) return 0;

   183     // get a correctly typed pointer to the list

   184     cx_array_list *arl = (cx_array_list *) list;

   186     // do we need to move some elements?

   187     if (index < list->size) {

   188         char const *first_to_move = (char const *) arl->data;

   189         first_to_move += index * list->itemsize;

   190         size_t elems_to_move = list->size - index;

   191         size_t start_of_moved = index + n;

   193         if (CX_ARRAY_COPY_SUCCESS != cx_array_copy(

   194                 &arl->data,

   195                 &list->size,

   196                 &list->capacity,

   197                 start_of_moved,

   198                 first_to_move,

   199                 list->itemsize,

   200                 elems_to_move,

   201                 &arl->reallocator

   202         )) {

   203             // if moving existing elems is unsuccessful, abort

   204             return 0;

   205         }

   206     }

   208     // note that if we had to move the elements, the following operation

   209     // is guaranteed to succeed, because we have the memory already allocated

   210     // therefore, it is impossible to leave this function with an invalid array

   212     // place the new elements

   213     if (CX_ARRAY_COPY_SUCCESS == cx_array_copy(

   214             &arl->data,

   215             &list->size,

   216             &list->capacity,

   217             index,

   218             array,

   219             list->itemsize,

   220             n,

   221             &arl->reallocator

   222     )) {

   223         return n;

   224     } else {

   225         // array list implementation is "all or nothing"

   226         return 0;

   227     }

   228 }

   230 static int cx_arl_insert_element(

   231         struct cx_list_s *list,

   232         size_t index,

   233         void const *element

   234 ) {

   235     return 1 != cx_arl_insert_array(list, index, element, 1);

   236 }

   238 static int cx_arl_insert_iter(

   239         struct cx_mut_iterator_s *iter,

   240         void const *elem,

   241         int prepend

   242 ) {

   243     struct cx_list_s *list = iter->src_handle;

   244     if (iter->index < list->size) {

   245         int result = cx_arl_insert_element(

   246                 list,

   247                 iter->index + 1 - prepend,

   248                 elem

   249         );

   250         if (result == 0 && prepend != 0) {

   251             iter->index++;

   252             iter->elem_handle = ((char *) iter->elem_handle) + list->itemsize;

   253         }

   254         return result;

   255     } else {

   256         int result = cx_arl_insert_element(list, list->size, elem);

   257         iter->index = list->size;

   258         return result;

   259     }

   260 }

   262 static int cx_arl_remove(

   263         struct cx_list_s *list,

   264         size_t index

   265 ) {

   266     // out-of-bounds check

   267     if (index >= list->size) {

   268         return 1;

   269     }

   271     // short-circuit removal of last element

   272     if (index == list->size - 1) {

   273         list->size--;

   274         return 0;

   275     }

   277     // just move the elements starting at index to the left

   278     cx_array_list *arl = (cx_array_list *) list;

   279     int result = cx_array_copy(

   280             &arl->data,

   281             &list->size,

   282             &list->capacity,

   283             index,

   284             ((char *) arl->data) + (index + 1) * list->itemsize,

   285             list->itemsize,

   286             list->size - index - 1,

   287             &arl->reallocator

   288     );

   289     if (result == 0) {

   290         // decrease the size

   291         list->size--;

   292     }

   293     return result;

   294 }

   296 static int cx_arl_swap(

   297         struct cx_list_s *list,

   298         size_t i,

   299         size_t j

   300 ) {

   301     if (i >= list->size || j >= list->size) return 1;

   302     cx_array_list *arl = (cx_array_list *) list;

   303     cx_array_swap(arl->data, list->itemsize, i, j);

   304     return 0;

   305 }

   307 static void *cx_arl_at(

   308         struct cx_list_s const *list,

   309         size_t index

   310 ) {

   311     if (index < list->size) {

   312         cx_array_list const *arl = (cx_array_list const *) list;

   313         char *space = arl->data;

   314         return space + index * list->itemsize;

   315     } else {

   316         return NULL;

   317     }

   318 }

   320 static size_t cx_arl_find(

   321         struct cx_list_s const *list,

   322         void const *elem

   323 ) {

   324     assert(list->cmpfunc != NULL);

   325     char *cur = ((cx_array_list const *) list)->data;

   327     for (size_t i = 0; i < list->size; i++) {

   328         if (0 == list->cmpfunc(elem, cur)) {

   329             return i;

   330         }

   331         cur += list->itemsize;

   332     }

   334     return list->size;

   335 }

   337 static void cx_arl_sort(struct cx_list_s *list) {

   338     assert(list->cmpfunc != NULL);

   339     qsort(((cx_array_list *) list)->data,

   340           list->size,

   341           list->itemsize,

   342           list->cmpfunc

   343     );

   344 }

   346 static int cx_arl_compare(

   347         struct cx_list_s const *list,

   348         struct cx_list_s const *other

   349 ) {

   350     assert(list->cmpfunc != NULL);

   351     if (list->size == other->size) {

   352         char const *left = ((cx_array_list const *) list)->data;

   353         char const *right = ((cx_array_list const *) other)->data;

   354         for (size_t i = 0; i < list->size; i++) {

   355             int d = list->cmpfunc(left, right);

   356             if (d != 0) {

   357                 return d;

   358             }

   359             left += list->itemsize;

   360             right += other->itemsize;

   361         }

   362         return 0;

   363     } else {

   364         return list->size < other->size ? -1 : 1;

   365     }

   366 }

   368 static void cx_arl_reverse(struct cx_list_s *list) {

   369     if (list->size < 2) return;

   370     void *data = ((cx_array_list const *) list)->data;

   371     size_t half = list->size / 2;

   372     for (size_t i = 0; i < half; i++) {

   373         cx_array_swap(data, list->itemsize, i, list->size - 1 - i);

   374     }

   375 }

   377 static bool cx_arl_iter_valid(void const *it) {

   378     struct cx_iterator_s const *iter = it;

   379     struct cx_list_s const *list = iter->src_handle;

   380     return iter->index < list->size;

   381 }

   383 static void *cx_arl_iter_current(void const *it) {

   384     struct cx_iterator_s const *iter = it;

   385     return iter->elem_handle;

   386 }

   388 static void cx_arl_iter_next(void *it) {

   389     struct cx_iterator_base_s *itbase = it;

   390     if (itbase->remove) {

   391         struct cx_mut_iterator_s *iter = it;

   392         itbase->remove = false;

   393         cx_arl_remove(iter->src_handle, iter->index);

   394     } else {

   395         struct cx_iterator_s *iter = it;

   396         iter->index++;

   397         iter->elem_handle =

   398                 ((char *) iter->elem_handle)

   399                 + ((struct cx_list_s const *) iter->src_handle)->itemsize;

   400     }

   401 }

   403 static void cx_arl_iter_prev(void *it) {

   404     struct cx_iterator_base_s *itbase = it;

   405     struct cx_mut_iterator_s *iter = it;

   406     cx_array_list *const list = iter->src_handle;

   407     if (itbase->remove) {

   408         itbase->remove = false;

   409         cx_arl_remove(iter->src_handle, iter->index);

   410     }

   411     iter->index--;

   412     if (iter->index < list->base.size) {

   413         iter->elem_handle = ((char *) list->data)

   414                             + iter->index * list->base.itemsize;

   415     }

   416 }

   418 static bool cx_arl_iter_flag_rm(void *it) {

   419     struct cx_iterator_base_s *iter = it;

   420     if (iter->mutating) {

   421         iter->remove = true;

   422         return true;

   423     } else {

   424         return false;

   425     }

   426 }

   428 static struct cx_iterator_s cx_arl_iterator(

   429         struct cx_list_s const *list,

   430         size_t index,

   431         bool backwards

   432 ) {

   433     struct cx_iterator_s iter;

   435     iter.index = index;

   436     iter.src_handle = list;

   437     iter.elem_handle = cx_arl_at(list, index);

   438     iter.base.valid = cx_arl_iter_valid;

   439     iter.base.current = cx_arl_iter_current;

   440     iter.base.next = backwards ? cx_arl_iter_prev : cx_arl_iter_next;

   441     iter.base.flag_removal = cx_arl_iter_flag_rm;

   442     iter.base.remove = false;

   443     iter.base.mutating = false;

   445     return iter;

   446 }

   448 static cx_list_class cx_array_list_class = {

   449         cx_arl_destructor,

   450         cx_arl_insert_element,

   451         cx_arl_insert_array,

   452         cx_arl_insert_iter,

   453         cx_arl_remove,

   454         cx_arl_swap,

   455         cx_arl_at,

   456         cx_arl_find,

   457         cx_arl_sort,

   458         cx_arl_compare,

   459         cx_arl_reverse,

   460         cx_arl_iterator,

   461 };

   463 CxList *cxArrayListCreate(

   464         CxAllocator const *allocator,

   465         CxListComparator comparator,

   466         size_t item_size,

   467         size_t initial_capacity

   468 ) {

   469     cx_array_list *list = cxCalloc(allocator, 1, sizeof(cx_array_list));

   470     if (list == NULL) return NULL;

   472     list->data = cxCalloc(allocator, initial_capacity, item_size);

   473     if (list->data == NULL) {

   474         cxFree(allocator, list);

   475         return NULL;

   476     }

   478     list->base.cl = &cx_array_list_class;

   479     list->base.allocator = allocator;

   480     list->base.cmpfunc = comparator;

   481     list->base.itemsize = item_size;

   482     list->base.capacity = initial_capacity;

   484     // configure the reallocator

   485     list->reallocator.realloc = cx_arl_realloc;

   486     list->reallocator.ptr1 = (void *) allocator;

   488     return (CxList *) list;

   489 }

Mercurial > hg > ucx / file revision

src/array_list.c@4738a9065907

src/array_list.c