/*
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
*
* Copyright 2021 Mike Becker, Olaf Wintermann All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#include "cx/linked_list.h"
#include "cx/utils.h"
#include <string.h>
#include <assert.h>
// LOW LEVEL LINKED LIST FUNCTIONS
#define CX_LL_PTR(cur, off) (*(void**)(((char*)(cur))+(off)))
#define ll_prev(node) CX_LL_PTR(node, loc_prev)
#define ll_next(node) CX_LL_PTR(node, loc_next)
#define ll_advance(node) CX_LL_PTR(node, loc_advance)
#define ll_data(node) (((char*)(node))+loc_data)
void *cx_linked_list_at(
void const *start,
size_t start_index,
ptrdiff_t loc_advance,
size_t index
) {
assert(start != NULL);
assert(loc_advance >= 0);
size_t i = start_index;
void const *cur = start;
while (i != index && cur != NULL) {
cur = ll_advance(cur);
i < index ? i++ : i--;
}
return (void *) cur;
}
ssize_t cx_linked_list_find(
void const *start,
ptrdiff_t loc_advance,
ptrdiff_t loc_data,
cx_compare_func cmp_func,
void const *elem
) {
assert(start != NULL);
assert(loc_advance >= 0);
assert(loc_data >= 0);
assert(cmp_func);
void const *node = start;
ssize_t index = 0;
do {
void *current = ll_data(node);
if (cmp_func(current, elem) == 0) {
return index;
}
node = ll_advance(node);
index++;
} while (node != NULL);
return -1;
}
void *cx_linked_list_first(
void const *node,
ptrdiff_t loc_prev
) {
return cx_linked_list_last(node, loc_prev);
}
void *cx_linked_list_last(
void const *node,
ptrdiff_t loc_next
) {
assert(node != NULL);
assert(loc_next >= 0);
void const *cur = node;
void const *last;
do {
last = cur;
} while ((cur = ll_next(cur)) != NULL);
return (void *) last;
}
void *cx_linked_list_prev(
void const *begin,
ptrdiff_t loc_next,
void const *node
) {
assert(begin != NULL);
assert(node != NULL);
assert(loc_next >= 0);
if (begin == node) return NULL;
void const *cur = begin;
void const *next;
while (1) {
next = ll_next(cur);
if (next == node) return (void *) cur;
cur = next;
}
}
void cx_linked_list_link(
void *left,
void *right,
ptrdiff_t loc_prev,
ptrdiff_t loc_next
) {
assert(loc_next >= 0);
ll_next(left) = right;
if (loc_prev >= 0) {
ll_prev(right) = left;
}
}
void cx_linked_list_unlink(
void *left,
void *right,
ptrdiff_t loc_prev,
ptrdiff_t loc_next
) {
assert (loc_next >= 0);
assert(ll_next(left) == right);
ll_next(left) = NULL;
if (loc_prev >= 0) {
assert(ll_prev(right) == left);
ll_prev(right) = NULL;
}
}
void cx_linked_list_add(
void **begin,
void **end,
ptrdiff_t loc_prev,
ptrdiff_t loc_next,
void *new_node
) {
void *last;
if (end == NULL) {
assert(begin != NULL);
last = *begin == NULL ? NULL : cx_linked_list_last(*begin, loc_next);
} else {
last = *end;
}
cx_linked_list_insert_chain(begin, end, loc_prev, loc_next, last, new_node, new_node);
}
void cx_linked_list_prepend(
void **begin,
void **end,
ptrdiff_t loc_prev,
ptrdiff_t loc_next,
void *new_node
) {
cx_linked_list_insert_chain(begin, end, loc_prev, loc_next, NULL, new_node, new_node);
}
void cx_linked_list_insert(
void **begin,
void **end,
ptrdiff_t loc_prev,
ptrdiff_t loc_next,
void *node,
void *new_node
) {
cx_linked_list_insert_chain(begin, end, loc_prev, loc_next, node, new_node, new_node);
}
void cx_linked_list_insert_chain(
void **begin,
void **end,
ptrdiff_t loc_prev,
ptrdiff_t loc_next,
void *node,
void *insert_begin,
void *insert_end
) {
// find the end of the chain, if not specified
if (insert_end == NULL) {
insert_end = cx_linked_list_last(insert_begin, loc_next);
}
// determine the successor
void *successor;
if (node == NULL) {
assert(begin != NULL || (end != NULL && loc_prev >= 0));
if (begin != NULL) {
successor = *begin;
*begin = insert_begin;
} else {
successor = *end == NULL ? NULL : cx_linked_list_first(*end, loc_prev);
}
} else {
successor = ll_next(node);
cx_linked_list_link(node, insert_begin, loc_prev, loc_next);
}
if (successor == NULL) {
// the list ends with the new chain
if (end != NULL) {
*end = insert_end;
}
} else {
cx_linked_list_link(insert_end, successor, loc_prev, loc_next);
}
}
void cx_linked_list_remove(
void **begin,
void **end,
ptrdiff_t loc_prev,
ptrdiff_t loc_next,
void *node
) {
assert(node != NULL);
assert(loc_next >= 0);
assert(loc_prev >= 0 || begin != NULL);
// find adjacent nodes
void *next = ll_next(node);
void *prev;
if (loc_prev >= 0) {
prev = ll_prev(node);
} else {
prev = cx_linked_list_prev(*begin, loc_next, node);
}
// update next pointer of prev node, or set begin
if (prev == NULL) {
if (begin != NULL) {
*begin = next;
}
} else {
ll_next(prev) = next;
}
// update prev pointer of next node, or set end
if (next == NULL) {
if (end != NULL) {
*end = prev;
}
} else if (loc_prev >= 0) {
ll_prev(next) = prev;
}
}
size_t cx_linked_list_size(
void const *node,
ptrdiff_t loc_next
) {
assert(loc_next >= 0);
size_t size = 0;
while (node != NULL) {
node = ll_next(node);
size++;
}
return size;
}
#ifndef CX_LINKED_LIST_SORT_SBO_SIZE
#define CX_LINKED_LIST_SORT_SBO_SIZE 1024
#endif
static void cx_linked_list_sort_merge(
ptrdiff_t loc_prev,
ptrdiff_t loc_next,
ptrdiff_t loc_data,
size_t length,
void *ls,
void *le,
void *re,
cx_compare_func cmp_func,
void **begin,
void **end
) {
void *sbo[CX_LINKED_LIST_SORT_SBO_SIZE];
void **sorted = length >= CX_LINKED_LIST_SORT_SBO_SIZE ?
malloc(sizeof(void *) * length) : sbo;
if (sorted == NULL) abort();
void *rc, *lc;
lc = ls;
rc = le;
size_t n = 0;
while (lc && lc != le && rc != re) {
if (cmp_func(ll_data(lc), ll_data(rc)) <= 0) {
sorted[n] = lc;
lc = ll_next(lc);
} else {
sorted[n] = rc;
rc = ll_next(rc);
}
n++;
}
while (lc && lc != le) {
sorted[n] = lc;
lc = ll_next(lc);
n++;
}
while (rc && rc != re) {
sorted[n] = rc;
rc = ll_next(rc);
n++;
}
// Update pointer
if (loc_prev >= 0) ll_prev(sorted[0]) = NULL;
cx_for_n (i, length - 1) {
cx_linked_list_link(sorted[i], sorted[i + 1], loc_prev, loc_next);
}
ll_next(sorted[length - 1]) = NULL;
*begin = sorted[0];
*end = sorted[length-1];
if (sorted != sbo) {
free(sorted);
}
}
void cx_linked_list_sort( // NOLINT(misc-no-recursion) - purposely recursive function
void **begin,
void **end,
ptrdiff_t loc_prev,
ptrdiff_t loc_next,
ptrdiff_t loc_data,
cx_compare_func cmp_func
) {
assert(begin != NULL);
assert(loc_next >= 0);
assert(loc_data >= 0);
assert(cmp_func);
void *lc, *ls, *le, *re;
// set start node
ls = *begin;
// early exit when this list is empty
if (ls == NULL) return;
// check how many elements are already sorted
lc = ls;
size_t ln = 1;
while (ll_next(lc) != NULL && cmp_func(ll_data(ll_next(lc)), ll_data(lc)) > 0) {
lc = ll_next(lc);
ln++;
}
le = ll_next(lc);
// if first unsorted node is NULL, the list is already completely sorted
if (le != NULL) {
void *rc;
size_t rn = 1;
rc = le;
// skip already sorted elements
while (ll_next(rc) != NULL && cmp_func(ll_data(ll_next(rc)), ll_data(rc)) > 0) {
rc = ll_next(rc);
rn++;
}
re = ll_next(rc);
// {ls,...,le->prev} and {rs,...,re->prev} are sorted - merge them
void *sorted_begin, *sorted_end;
cx_linked_list_sort_merge(loc_prev, loc_next, loc_data,
ln + rn, ls, le, re, cmp_func,
&sorted_begin, &sorted_end);
// Something left? Sort it!
size_t remainder_length = cx_linked_list_size(re, loc_next);
if (remainder_length > 0) {
void *remainder = re;
cx_linked_list_sort(&remainder, NULL, loc_prev, loc_next, loc_data, cmp_func);
// merge sorted list with (also sorted) remainder
cx_linked_list_sort_merge(loc_prev, loc_next, loc_data,
ln + rn + remainder_length,
sorted_begin, remainder, NULL, cmp_func,
&sorted_begin, &sorted_end);
}
*begin = sorted_begin;
if (end) *end = sorted_end;
}
}
int cx_linked_list_compare(
void const *begin_left,
void const *begin_right,
ptrdiff_t loc_advance,
ptrdiff_t loc_data,
cx_compare_func cmp_func
) {
void const *left = begin_left, *right = begin_right;
while (left != NULL && right != NULL) {
void const *left_data = ll_data(left);
void const *right_data = ll_data(right);
int result = cmp_func(left_data, right_data);
if (result != 0) return result;
left = ll_advance(left);
right = ll_advance(right);
}
if (left != NULL) { return 1; }
else if (right != NULL) { return -1; }
else { return 0; }
}
void cx_linked_list_reverse(
void **begin,
void **end,
ptrdiff_t loc_prev,
ptrdiff_t loc_next
) {
assert(begin != NULL);
assert(loc_next >= 0);
// swap all links
void *prev = NULL;
void *cur = *begin;
while (cur != NULL) {
void *next = ll_next(cur);
ll_next(cur) = prev;
if (loc_prev >= 0) {
ll_prev(cur) = next;
}
prev = cur;
cur = next;
}
// update begin and end
if (end != NULL) {
*end = *begin;
}
*begin = prev;
}
// HIGH LEVEL LINKED LIST IMPLEMENTATION
bool CX_DISABLE_LINKED_LIST_SWAP_SBO = false;
typedef struct cx_linked_list_node cx_linked_list_node;
struct cx_linked_list_node {
cx_linked_list_node *prev;
cx_linked_list_node *next;
char payload[];
};
#define CX_LL_LOC_PREV offsetof(cx_linked_list_node, prev)
#define CX_LL_LOC_NEXT offsetof(cx_linked_list_node, next)
#define CX_LL_LOC_DATA offsetof(cx_linked_list_node, payload)
typedef struct {
struct cx_list_s base;
cx_linked_list_node *begin;
cx_linked_list_node *end;
} cx_linked_list;
static cx_linked_list_node *cx_ll_node_at(
cx_linked_list const *list,
size_t index
) {
if (index >= list->base.size) {
return NULL;
} else if (index > list->base.size / 2) {
return cx_linked_list_at(list->end, list->base.size - 1, CX_LL_LOC_PREV, index);
} else {
return cx_linked_list_at(list->begin, 0, CX_LL_LOC_NEXT, index);
}
}
static int cx_ll_insert_at(
struct cx_list_s *list,
cx_linked_list_node *node,
void const *elem
) {
// create the new new_node
cx_linked_list_node *new_node = cxMalloc(list->allocator,
sizeof(cx_linked_list_node) + list->item_size);
// sortir if failed
if (new_node == NULL) return 1;
// initialize new new_node
new_node->prev = new_node->next = NULL;
memcpy(new_node->payload, elem, list->item_size);
// insert
cx_linked_list *ll = (cx_linked_list *) list;
cx_linked_list_insert_chain(
(void **) &ll->begin, (void **) &ll->end,
CX_LL_LOC_PREV, CX_LL_LOC_NEXT,
node, new_node, new_node
);
// increase the size and return
list->size++;
return 0;
}
static size_t cx_ll_insert_array(
struct cx_list_s *list,
size_t index,
void const *array,
size_t n
) {
// out-of bounds and corner case check
if (index > list->size || n == 0) return 0;
// find position efficiently
cx_linked_list_node *node = index == 0 ? NULL : cx_ll_node_at((cx_linked_list *) list, index - 1);
// perform first insert
if (0 != cx_ll_insert_at(list, node, array)) {
return 1;
}
// is there more?
if (n == 1) return 1;
// we now know exactly where we are
node = node == NULL ? ((cx_linked_list *) list)->begin : node->next;
// we can add the remaining nodes and immedately advance to the inserted node
char const *source = array;
for (size_t i = 1; i < n; i++) {
source += list->item_size;
if (0 != cx_ll_insert_at(list, node, source)) {
return i;
}
node = node->next;
}
return n;
}
static int cx_ll_insert_element(
struct cx_list_s *list,
size_t index,
void const *element
) {
return 1 != cx_ll_insert_array(list, index, element, 1);
}
static int cx_ll_remove(
struct cx_list_s *list,
size_t index
) {
cx_linked_list *ll = (cx_linked_list *) list;
cx_linked_list_node *node = cx_ll_node_at(ll, index);
// out-of-bounds check
if (node == NULL) return 1;
// element destruction
cx_invoke_destructor(list, node->payload);
// remove
cx_linked_list_remove((void **) &ll->begin, (void **) &ll->end,
CX_LL_LOC_PREV, CX_LL_LOC_NEXT, node);
// adjust size
list->size--;
// free and return
cxFree(list->allocator, node);
return 0;
}
static void cx_ll_clear(struct cx_list_s *list) {
if (list->size == 0) return;
cx_linked_list *ll = (cx_linked_list *) list;
cx_linked_list_node *node = ll->begin;
while (node != NULL) {
cx_invoke_destructor(list, node->payload);
cx_linked_list_node *next = node->next;
cxFree(list->allocator, node);
node = next;
}
ll->begin = ll->end = NULL;
list->size = 0;
}
#ifndef CX_LINKED_LIST_SWAP_SBO_SIZE
#define CX_LINKED_LIST_SWAP_SBO_SIZE 128
#endif
static int cx_ll_swap(
struct cx_list_s *list,
size_t i,
size_t j
) {
if (i >= list->size || j >= list->size) return 1;
if (i == j) return 0;
// perform an optimized search that finds both elements in one run
cx_linked_list *ll = (cx_linked_list *) list;
size_t mid = list->size / 2;
size_t left, right;
if (i < j) {
left = i;
right = j;
} else {
left = j;
right = i;
}
cx_linked_list_node *nleft, *nright;
if (left < mid && right < mid) {
// case 1: both items left from mid
nleft = cx_ll_node_at(ll, left);
nright = nleft;
for (size_t c = left; c < right; c++) {
nright = nright->next;
}
} else if (left >= mid && right >= mid) {
// case 2: both items right from mid
nright = cx_ll_node_at(ll, right);
nleft = nright;
for (size_t c = right; c > left; c--) {
nleft = nleft->prev;
}
} else {
// case 3: one item left, one item right
// chose the closest to begin / end
size_t closest;
size_t other;
size_t diff2boundary = list->size - right - 1;
if (left <= diff2boundary) {
closest = left;
other = right;
nleft = cx_ll_node_at(ll, left);
} else {
closest = right;
other = left;
diff2boundary = left;
nright = cx_ll_node_at(ll, right);
}
// is other element closer to us or closer to boundary?
if (right - left <= diff2boundary) {
// search other element starting from already found element
if (closest == left) {
nright = nleft;
for (size_t c = left; c < right; c++) {
nright = nright->next;
}
} else {
nleft = nright;
for (size_t c = right; c > left; c--) {
nleft = nleft->prev;
}
}
} else {
// search other element starting at the boundary
if (closest == left) {
nright = cx_ll_node_at(ll, other);
} else {
nleft = cx_ll_node_at(ll, other);
}
}
}
if (list->item_size > CX_LINKED_LIST_SWAP_SBO_SIZE || CX_DISABLE_LINKED_LIST_SWAP_SBO) {
cx_linked_list_node *prev = nleft->prev;
cx_linked_list_node *next = nright->next;
cx_linked_list_node *midstart = nleft->next;
cx_linked_list_node *midend = nright->prev;
if (prev == NULL) {
ll->begin = nright;
} else {
prev->next = nright;
}
nright->prev = prev;
if (midstart == nright) {
// special case: both nodes are adjacent
nright->next = nleft;
nleft->prev = nright;
} else {
// likely case: a chain is between the two nodes
nright->next = midstart;
midstart->prev = nright;
midend->next = nleft;
nleft->prev = midend;
}
nleft->next = next;
if (next == NULL) {
ll->end = nleft;
} else {
next->prev = nleft;
}
} else {
// swap payloads to avoid relinking
char buf[CX_LINKED_LIST_SWAP_SBO_SIZE];
memcpy(buf, nleft->payload, list->item_size);
memcpy(nleft->payload, nright->payload, list->item_size);
memcpy(nright->payload, buf, list->item_size);
}
return 0;
}
static void *cx_ll_at(
struct cx_list_s const *list,
size_t index
) {
cx_linked_list *ll = (cx_linked_list *) list;
cx_linked_list_node *node = cx_ll_node_at(ll, index);
return node == NULL ? NULL : node->payload;
}
static ssize_t cx_ll_find(
struct cx_list_s const *list,
void const *elem
) {
return cx_linked_list_find(((cx_linked_list *) list)->begin,
CX_LL_LOC_NEXT, CX_LL_LOC_DATA,
list->cmpfunc, elem);
}
static void cx_ll_sort(struct cx_list_s *list) {
cx_linked_list *ll = (cx_linked_list *) list;
cx_linked_list_sort((void **) &ll->begin, (void **) &ll->end,
CX_LL_LOC_PREV, CX_LL_LOC_NEXT, CX_LL_LOC_DATA,
list->cmpfunc);
}
static void cx_ll_reverse(struct cx_list_s *list) {
cx_linked_list *ll = (cx_linked_list *) list;
cx_linked_list_reverse((void **) &ll->begin, (void **) &ll->end, CX_LL_LOC_PREV, CX_LL_LOC_NEXT);
}
static int cx_ll_compare(
struct cx_list_s const *list,
struct cx_list_s const *other
) {
cx_linked_list *left = (cx_linked_list *) list;
cx_linked_list *right = (cx_linked_list *) other;
return cx_linked_list_compare(left->begin, right->begin,
CX_LL_LOC_NEXT, CX_LL_LOC_DATA,
list->cmpfunc);
}
static bool cx_ll_iter_valid(void const *it) {
struct cx_iterator_s const *iter = it;
return iter->elem_handle != NULL;
}
static void cx_ll_iter_next(void *it) {
struct cx_iterator_base_s *itbase = it;
if (itbase->remove) {
itbase->remove = false;
struct cx_mut_iterator_s *iter = it;
struct cx_list_s *list = iter->src_handle;
cx_linked_list *ll = iter->src_handle;
cx_linked_list_node *node = iter->elem_handle;
iter->elem_handle = node->next;
cx_invoke_destructor(list, node->payload);
cx_linked_list_remove((void **) &ll->begin, (void **) &ll->end,
CX_LL_LOC_PREV, CX_LL_LOC_NEXT, node);
list->size--;
cxFree(list->allocator, node);
} else {
struct cx_iterator_s *iter = it;
iter->index++;
cx_linked_list_node *node = iter->elem_handle;
iter->elem_handle = node->next;
}
}
static void cx_ll_iter_prev(void *it) {
struct cx_iterator_base_s *itbase = it;
if (itbase->remove) {
itbase->remove = false;
struct cx_mut_iterator_s *iter = it;
struct cx_list_s *list = iter->src_handle;
cx_linked_list *ll = iter->src_handle;
cx_linked_list_node *node = iter->elem_handle;
iter->elem_handle = node->prev;
iter->index--;
cx_invoke_destructor(list, node->payload);
cx_linked_list_remove((void **) &ll->begin, (void **) &ll->end,
CX_LL_LOC_PREV, CX_LL_LOC_NEXT, node);
list->size--;
cxFree(list->allocator, node);
} else {
struct cx_iterator_s *iter = it;
iter->index--;
cx_linked_list_node *node = iter->elem_handle;
iter->elem_handle = node->prev;
}
}
static void *cx_ll_iter_current(void const *it) {
struct cx_iterator_s const *iter = it;
cx_linked_list_node *node = iter->elem_handle;
return node->payload;
}
static bool cx_ll_iter_flag_rm(void *it) {
struct cx_iterator_base_s *iter = it;
if (iter->mutating) {
iter->remove = true;
return true;
} else {
return false;
}
}
static CxIterator cx_ll_iterator(
struct cx_list_s const *list,
size_t index,
bool backwards
) {
CxIterator iter;
iter.index = index;
iter.src_handle = list;
iter.elem_handle = cx_ll_node_at((cx_linked_list const *) list, index);
iter.base.valid = cx_ll_iter_valid;
iter.base.current = cx_ll_iter_current;
iter.base.next = backwards ? cx_ll_iter_prev : cx_ll_iter_next;
iter.base.flag_removal = cx_ll_iter_flag_rm;
iter.base.mutating = false;
iter.base.remove = false;
return iter;
}
static int cx_ll_insert_iter(
CxMutIterator *iter,
void const *elem,
int prepend
) {
struct cx_list_s *list = iter->src_handle;
cx_linked_list_node *node = iter->elem_handle;
if (node != NULL) {
assert(prepend >= 0 && prepend <= 1);
cx_linked_list_node *choice[2] = {node, node->prev};
int result = cx_ll_insert_at(list, choice[prepend], elem);
iter->index += prepend * (0 == result);
return result;
} else {
int result = cx_ll_insert_element(list, list->size, elem);
iter->index = list->size;
return result;
}
}
static void cx_ll_destructor(CxList *list) {
cx_linked_list *ll = (cx_linked_list *) list;
cx_linked_list_node *node = ll->begin;
while (node) {
cx_invoke_destructor(list, node->payload);
void *next = node->next;
cxFree(list->allocator, node);
node = next;
}
cxFree(list->allocator, list);
}
static cx_list_class cx_linked_list_class = {
cx_ll_destructor,
cx_ll_insert_element,
cx_ll_insert_array,
cx_ll_insert_iter,
cx_ll_remove,
cx_ll_clear,
cx_ll_swap,
cx_ll_at,
cx_ll_find,
cx_ll_sort,
cx_ll_compare,
cx_ll_reverse,
cx_ll_iterator,
};
CxList *cxLinkedListCreate(
CxAllocator const *allocator,
cx_compare_func comparator,
size_t item_size
) {
if (allocator == NULL) {
allocator = cxDefaultAllocator;
}
cx_linked_list *list = cxCalloc(allocator, 1, sizeof(cx_linked_list));
if (list == NULL) return NULL;
list->base.cl = &cx_linked_list_class;
list->base.allocator = allocator;
list->base.cmpfunc = comparator;
if (item_size > 0) {
list->base.item_size = item_size;
} else {
cxListStorePointers((CxList *) list);
}
return (CxList *) list;
}