ucx: src/array_list.c@5700ba9154ab

     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 minsize = index + elem_count;

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

    57     bool needrealloc = newsize > cap;

    59     // reallocate if possible

    60     if (needrealloc) {

    61         // a reallocator and a capacity variable must be available

    62         if (reallocator == NULL || capacity == NULL) {

    63             return CX_ARRAY_COPY_REALLOC_NOT_SUPPORTED;

    64         }

    66         // check, if we need to repair the src pointer

    67         uintptr_t targetaddr = (uintptr_t) *target;

    68         uintptr_t srcaddr = (uintptr_t) src;

    69         bool repairsrc = targetaddr <= srcaddr

    70                          && srcaddr < targetaddr + cap * elem_size;

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

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

    74         assert(cap > newsize);

    76         // perform reallocation

    77         void *newmem = reallocator->realloc(

    78                 *target, cap, elem_size, reallocator

    79         );

    80         if (newmem == NULL) {

    81             return CX_ARRAY_COPY_REALLOC_FAILED;

    82         }

    84         // repair src pointer, if necessary

    85         if (repairsrc) {

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

    87         }

    89         // store new pointer and capacity

    90         *target = newmem;

    91         *capacity = cap;

    92     }

    94     // determine target pointer

    95     char *start = *target;

    96     start += index * elem_size;

    98     // copy elements and set new size

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

   100     *size = newsize;

   102     // return successfully

   103     return CX_ARRAY_COPY_SUCCESS;

   104 }

   106 #ifndef CX_ARRAY_SWAP_SBO_SIZE

   107 #define CX_ARRAY_SWAP_SBO_SIZE 512

   108 #endif

   110 void cx_array_swap(

   111         void *arr,

   112         size_t elem_size,

   113         size_t idx1,

   114         size_t idx2

   115 ) {

   116     // short circuit

   117     if (idx1 == idx2) return;

   119     char sbo_mem[CX_ARRAY_SWAP_SBO_SIZE];

   120     void *tmp;

   122     // decide if we can use the local buffer

   123     if (elem_size > CX_ARRAY_SWAP_SBO_SIZE) {

   124         tmp = malloc(elem_size);

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

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

   127     } else {

   128         tmp = sbo_mem;

   129     }

   131     // calculate memory locations

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

   133     left += idx1 * elem_size;

   134     right += idx2 * elem_size;

   136     // three-way swap

   137     memcpy(tmp, left, elem_size);

   138     memcpy(left, right, elem_size);

   139     memcpy(right, tmp, elem_size);

   141     // free dynamic memory, if it was needed

   142     if (tmp != sbo_mem) {

   143         free(tmp);

   144     }

   145 }

   147 // HIGH LEVEL ARRAY LIST FUNCTIONS

   149 typedef struct {

   150     struct cx_list_s base;

   151     void *data;

   152     struct cx_array_reallocator_s reallocator;

   153 } cx_array_list;

   155 static void *cx_arl_realloc(

   156         void *array,

   157         size_t capacity,

   158         size_t elem_size,

   159         struct cx_array_reallocator_s *alloc

   160 ) {

   161     // retrieve the pointer to the list allocator

   162     CxAllocator const *al = alloc->ptr1;

   164     // use the list allocator to reallocate the memory

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

   166 }

   168 static void cx_arl_destructor(struct cx_list_s *list) {

   169     cx_array_list *arl = (cx_array_list *) list;

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

   171 }

   173 static size_t cx_arl_insert_array(

   174         struct cx_list_s *list,

   175         size_t index,

   176         void const *array,

   177         size_t n

   178 ) {

   179     // out of bounds and special case check

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

   182     // get a correctly typed pointer to the list

   183     cx_array_list *arl = (cx_array_list *) list;

   185     // do we need to move some elements?

   186     if (index < list->size) {

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

   188         first_to_move += index * list->itemsize;

   189         size_t elems_to_move = list->size - index;

   190         size_t start_of_moved = index + n;

   192         if (CX_ARRAY_COPY_SUCCESS != cx_array_copy(

   193                 &arl->data,

   194                 &list->size,

   195                 &list->capacity,

   196                 start_of_moved,

   197                 first_to_move,

   198                 list->itemsize,

   199                 elems_to_move,

   200                 &arl->reallocator

   201         )) {

   202             // if moving existing elems is unsuccessful, abort

   203             return 0;

   204         }

   205     }

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

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

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

   211     // place the new elements

   212     if (CX_ARRAY_COPY_SUCCESS == cx_array_copy(

   213             &arl->data,

   214             &list->size,

   215             &list->capacity,

   216             index,

   217             array,

   218             list->itemsize,

   219             n,

   220             &arl->reallocator

   221     )) {

   222         return n;

   223     } else {

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

   225         return 0;

   226     }

   227 }

   229 static int cx_arl_insert_element(

   230         struct cx_list_s *list,

   231         size_t index,

   232         void const *element

   233 ) {

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

   235 }

   237 static int cx_arl_insert_iter(

   238         struct cx_mut_iterator_s *iter,

   239         void const *elem,

   240         int prepend

   241 ) {

   242     struct cx_list_s *list = iter->src_handle;

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

   244         int result = cx_arl_insert_element(

   245                 list,

   246                 iter->index + 1 - prepend,

   247                 elem

   248         );

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

   250             iter->index++;

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

   252         }

   253         return result;

   254     } else {

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

   256         iter->index = list->size;

   257         return result;

   258     }

   259 }

   261 static int cx_arl_remove(

   262         struct cx_list_s *list,

   263         size_t index

   264 ) {

   265     // out-of-bounds check

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

   267         return 1;

   268     }

   270     // short-circuit removal of last element

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

   272         list->size--;

   273         return 0;

   274     }

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

   277     cx_array_list *arl = (cx_array_list *) list;

   278     int result = cx_array_copy(

   279             &arl->data,

   280             &list->size,

   281             &list->capacity,

   282             index,

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

   284             list->itemsize,

   285             list->size - index - 1,

   286             &arl->reallocator

   287     );

   288     if (result == 0) {

   289         // decrease the size

   290         list->size--;

   291     }

   292     return result;

   293 }

   295 static void *cx_arl_at(

   296         struct cx_list_s const *list,

   297         size_t index

   298 ) {

   299     if (index < list->size) {

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

   301         char *space = arl->data;

   302         return space + index * list->itemsize;

   303     } else {

   304         return NULL;

   305     }

   306 }

   308 static size_t cx_arl_find(

   309         struct cx_list_s const *list,

   310         void const *elem

   311 ) {

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

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

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

   316             return i;

   317         }

   318         cur += list->itemsize;

   319     }

   321     return list->size;

   322 }

   324 static void cx_arl_sort(struct cx_list_s *list) {

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

   326           list->size,

   327           list->itemsize,

   328           list->cmpfunc

   329     );

   330 }

   332 static int cx_arl_compare(

   333         struct cx_list_s const *list,

   334         struct cx_list_s const *other

   335 ) {

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

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

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

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

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

   341             if (d != 0) {

   342                 return d;

   343             }

   344             left += list->itemsize;

   345             right += other->itemsize;

   346         }

   347         return 0;

   348     } else {

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

   350     }

   351 }

   353 static void cx_arl_reverse(struct cx_list_s *list) {

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

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

   356     size_t half = list->size / 2;

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

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

   359     }

   360 }

   362 static bool cx_arl_iter_valid(void const *it) {

   363     struct cx_iterator_s const *iter = it;

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

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

   366 }

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

   369     struct cx_iterator_s const *iter = it;

   370     return iter->elem_handle;

   371 }

   373 static void cx_arl_iter_next(void *it) {

   374     struct cx_iterator_base_s *itbase = it;

   375     if (itbase->remove) {

   376         struct cx_mut_iterator_s *iter = it;

   377         itbase->remove = false;

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

   379     } else {

   380         struct cx_iterator_s *iter = it;

   381         iter->index++;

   382         iter->elem_handle =

   383                 ((char *) iter->elem_handle)

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

   385     }

   386 }

   388 static bool cx_arl_iter_flag_rm(void *it) {

   389     struct cx_iterator_base_s *iter = it;

   390     if (iter->mutating) {

   391         iter->remove = true;

   392         return true;

   393     } else {

   394         return false;

   395     }

   396 }

   398 static struct cx_iterator_s cx_arl_iterator(

   399         struct cx_list_s const *list,

   400         size_t index

   401 ) {

   402     struct cx_iterator_s iter;

   404     iter.index = index;

   405     iter.src_handle = list;

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

   407     iter.base.valid = cx_arl_iter_valid;

   408     iter.base.current = cx_arl_iter_current;

   409     iter.base.next = cx_arl_iter_next;

   410     iter.base.flag_removal = cx_arl_iter_flag_rm;

   411     iter.base.remove = false;

   412     iter.base.mutating = false;

   414     return iter;

   415 }

   417 static cx_list_class cx_array_list_class = {

   418         cx_arl_destructor,

   419         cx_arl_insert_element,

   420         cx_arl_insert_array,

   421         cx_arl_insert_iter,

   422         cx_arl_remove,

   423         cx_arl_at,

   424         cx_arl_find,

   425         cx_arl_sort,

   426         cx_arl_compare,

   427         cx_arl_reverse,

   428         cx_arl_iterator,

   429 };

   431 CxList *cxArrayListCreate(

   432         CxAllocator const *allocator,

   433         CxListComparator comparator,

   434         size_t item_size,

   435         size_t initial_capacity

   436 ) {

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

   438     if (list == NULL) return NULL;

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

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

   442         cxFree(allocator, list);

   443         return NULL;

   444     }

   446     list->base.cl = &cx_array_list_class;

   447     list->base.allocator = allocator;

   448     list->base.cmpfunc = comparator;

   449     list->base.itemsize = item_size;

   450     list->base.capacity = initial_capacity;

   452     // configure the reallocator

   453     list->reallocator.realloc = cx_arl_realloc;

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

   456     return (CxList *) list;

   457 }

Mercurial > hg > ucx / file revision

src/array_list.c@5700ba9154ab

src/array_list.c