Problem - Kevin Tafuro

}
/* Create an array folded 'layers' times, with num_elem elements */
spc_array_t *spc_array_fold(int sz_elem, int num_elem, int layers) {
double size = (sz_elem * num_elem) + sizeof(spc_array_t);
spc_array_t *a;
size = ((double)sz_elem * (double)num_elem) + (double)sizeof(spc_array_t);
if (size > (double)INT_MAX) return 0;
if (!(a = (spc_array_t *)calloc((size_t)size, 1))) return 0;
a->type = SPC_ARRAY_FOLD;
a->sz_elem = sz_elem;
a->num_elem = num_elem;
a->split = layers;
return a;
}
/* Create a flattened array of num_dimen dimensions with num_elem elements per
* dimension, flattened to a single dimension
*/
spc_array_t *spc_array_flat(int sz_elem, int num_elem, int num_dimen) {
double size;
spc_array_t *a;
size = ((double)sz_elem * (double)num_elem * (double)num_dimen) +
(double)sizeof(spc_array_t);
if (size > (double)INT_MAX) return 0;
if (!(a = (spc_array_t *)calloc((size_t)size, 1))) return 0;
a->type = SPC_ARRAY_FLAT;
a->sz_elem = sz_elem;
a->num_elem = num_elem * num_dimen;
a->split = num_dimen;
return a;
}
/* return the real index of element 'idx' in array 'subarray' */
static int array_index(spc_array_t *a, int subarray, int idx) {
int index = -1, num_row, diff;
num_row = a->num_elem / a->split;
switch (a->type) {
case SPC_ARRAY_SPLIT:
if (idx % a->split) index = idx / a->split;
else index = (a->num_elem / a->split) + (idx / a->split);
break;
case SPC_ARRAY_MERGE:
/* a->split = = size diff between array 1 and 2 */
if (a->split < 0) {
subarray = !subarray;
diff = a->split * -1;
} else diff = a->split;
if (!subarray) index = idx + idx / diff;
else index = diff + (idx * (diff + 1));
674 | Chapter 12: Anti-Tampering
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