Function ScanKeyListToArray

src/backend/executor/nodeSeqscan.c:452–473

* Convert the list of ScanKey to the array, and append an emtpy ScanKey as * the end flag of the array. */

 * the end flag of the array.
 */
static ScanKey
ScanKeyListToArray(List *keys, int *num)
{
	ScanKey sk;

	if (list_length(keys) == 0)
		return NULL;

	Assert(num);
	*num = list_length(keys);

	sk = (ScanKey)palloc(sizeof(ScanKeyData) * (*num + 1));
	for (int i = 0; i < *num; ++i)
		memcpy(&sk[i], list_nth(keys, i), sizeof(ScanKeyData));

	/*
	 * SK_EMPYT means the end of the array of the ScanKey
	 */
	sk[*num].sk_flags = SK_EMPYT;

	return sk;
}