pvjc25/du6/list_ops.c

49 lines
1.4 KiB
C

#include "list_ops.h"
#include <string.h>
list_t *new_list(size_t length, list_element_t elements[]) {
list_t *list = malloc(sizeof(list_t) + sizeof(list_element_t) * length);
if (!list) return NULL;
list->length = length;
if (elements && length > 0) {
memcpy(list->elements, elements, sizeof(list_element_t) * length);
}
return list;
}
list_t *append_list(list_t *list1, list_t *list2) {
size_t len1 = list1 ? list1->length : 0;
size_t len2 = list2 ? list2->length : 0;
list_t *result = malloc(sizeof(list_t) + sizeof(list_element_t) * (len1 + len2));
if (!result) return NULL;
result->length = len1 + len2;
if (len1 > 0)
memcpy(result->elements, list1->elements, sizeof(list_element_t) * len1);
if (len2 > 0)
memcpy(result->elements + len1, list2->elements, sizeof(list_element_t) * len2);
return result;
}
list_t *filter_list(list_t *list, bool (*filter)(list_element_t)) {
if (!list || list->length == 0) return new_list(0, NULL);
list_element_t *temp = malloc(sizeof(list_element_t) * list->length);
if (!temp) return NULL;
size_t count = 0;
for (size_t i = 0; i < list->length; ++i) {
if (filter(list->elements[i])) {
temp[count++] = list->elements[i];
}
}
list_t *result = new_list(count, temp);
free(temp);
return result;
}
size_t length_list(list_t *list) {
return list ? list->length : 0;
}