/*--------------------------------------------------------------------------
 *
 * test_lfind.c
 *		Test correctness of optimized linear search functions.
 *
 * Copyright (c) 2022-2025, PostgreSQL Global Development Group
 *
 * IDENTIFICATION
 *		src/test/modules/test_lfind/test_lfind.c
 *
 * -------------------------------------------------------------------------
 */

#include "postgres.h"

#include "fmgr.h"
#include "port/pg_lfind.h"

/*
 * Convenience macros for testing both vector and scalar operations. The 2x
 * factor is to make sure iteration works
 */
#define LEN_NO_TAIL(vectortype) (2 * sizeof(vectortype))
#define LEN_WITH_TAIL(vectortype) (LEN_NO_TAIL(vectortype) + 3)

PG_MODULE_MAGIC;

/* workhorse for test_lfind8 */
static void
test_lfind8_internal(uint8 key)
{
	uint8		charbuf[LEN_WITH_TAIL(Vector8)];
	const int	len_no_tail = LEN_NO_TAIL(Vector8);
	const int	len_with_tail = LEN_WITH_TAIL(Vector8);

	memset(charbuf, 0xFF, len_with_tail);
	/* search tail to test one-byte-at-a-time path */
	charbuf[len_with_tail - 1] = key;
	if (key > 0x00 && pg_lfind8(key - 1, charbuf, len_with_tail))
		elog(ERROR, "pg_lfind8() found nonexistent element '0x%x'", key - 1);
	if (key < 0xFF && !pg_lfind8(key, charbuf, len_with_tail))
		elog(ERROR, "pg_lfind8() did not find existing element '0x%x'", key);
	if (key < 0xFE && pg_lfind8(key + 1, charbuf, len_with_tail))
		elog(ERROR, "pg_lfind8() found nonexistent element '0x%x'", key + 1);

	memset(charbuf, 0xFF, len_with_tail);
	/* search with vector operations */
	charbuf[len_no_tail - 1] = key;
	if (key > 0x00 && pg_lfind8(key - 1, charbuf, len_no_tail))
		elog(ERROR, "pg_lfind8() found nonexistent element '0x%x'", key - 1);
	if (key < 0xFF && !pg_lfind8(key, charbuf, len_no_tail))
		elog(ERROR, "pg_lfind8() did not find existing element '0x%x'", key);
	if (key < 0xFE && pg_lfind8(key + 1, charbuf, len_no_tail))
		elog(ERROR, "pg_lfind8() found nonexistent element '0x%x'", key + 1);
}

PG_FUNCTION_INFO_V1(test_lfind8);
Datum
test_lfind8(PG_FUNCTION_ARGS)
{
	test_lfind8_internal(0);
	test_lfind8_internal(1);
	test_lfind8_internal(0x7F);
	test_lfind8_internal(0x80);
	test_lfind8_internal(0x81);
	test_lfind8_internal(0xFD);
	test_lfind8_internal(0xFE);
	test_lfind8_internal(0xFF);

	PG_RETURN_VOID();
}

/* workhorse for test_lfind8_le */
static void
test_lfind8_le_internal(uint8 key)
{
	uint8		charbuf[LEN_WITH_TAIL(Vector8)];
	const int	len_no_tail = LEN_NO_TAIL(Vector8);
	const int	len_with_tail = LEN_WITH_TAIL(Vector8);

	memset(charbuf, 0xFF, len_with_tail);
	/* search tail to test one-byte-at-a-time path */
	charbuf[len_with_tail - 1] = key;
	if (key > 0x00 && pg_lfind8_le(key - 1, charbuf, len_with_tail))
		elog(ERROR, "pg_lfind8_le() found nonexistent element <= '0x%x'", key - 1);
	if (key < 0xFF && !pg_lfind8_le(key, charbuf, len_with_tail))
		elog(ERROR, "pg_lfind8_le() did not find existing element <= '0x%x'", key);
	if (key < 0xFE && !pg_lfind8_le(key + 1, charbuf, len_with_tail))
		elog(ERROR, "pg_lfind8_le() did not find existing element <= '0x%x'", key + 1);

	memset(charbuf, 0xFF, len_with_tail);
	/* search with vector operations */
	charbuf[len_no_tail - 1] = key;
	if (key > 0x00 && pg_lfind8_le(key - 1, charbuf, len_no_tail))
		elog(ERROR, "pg_lfind8_le() found nonexistent element <= '0x%x'", key - 1);
	if (key < 0xFF && !pg_lfind8_le(key, charbuf, len_no_tail))
		elog(ERROR, "pg_lfind8_le() did not find existing element <= '0x%x'", key);
	if (key < 0xFE && !pg_lfind8_le(key + 1, charbuf, len_no_tail))
		elog(ERROR, "pg_lfind8_le() did not find existing element <= '0x%x'", key + 1);
}

PG_FUNCTION_INFO_V1(test_lfind8_le);
Datum
test_lfind8_le(PG_FUNCTION_ARGS)
{
	test_lfind8_le_internal(0);
	test_lfind8_le_internal(1);
	test_lfind8_le_internal(0x7F);
	test_lfind8_le_internal(0x80);
	test_lfind8_le_internal(0x81);
	test_lfind8_le_internal(0xFD);
	test_lfind8_le_internal(0xFE);
	test_lfind8_le_internal(0xFF);

	PG_RETURN_VOID();
}

PG_FUNCTION_INFO_V1(test_lfind32);
Datum
test_lfind32(PG_FUNCTION_ARGS)
{
#define TEST_ARRAY_SIZE 135
	uint32		test_array[TEST_ARRAY_SIZE] = {0};

	test_array[8] = 1;
	test_array[64] = 2;
	test_array[TEST_ARRAY_SIZE - 1] = 3;

	if (pg_lfind32(1, test_array, 4))
		elog(ERROR, "pg_lfind32() found nonexistent element");
	if (!pg_lfind32(1, test_array, TEST_ARRAY_SIZE))
		elog(ERROR, "pg_lfind32() did not find existing element");

	if (pg_lfind32(2, test_array, 32))
		elog(ERROR, "pg_lfind32() found nonexistent element");
	if (!pg_lfind32(2, test_array, TEST_ARRAY_SIZE))
		elog(ERROR, "pg_lfind32() did not find existing element");

	if (pg_lfind32(3, test_array, 96))
		elog(ERROR, "pg_lfind32() found nonexistent element");
	if (!pg_lfind32(3, test_array, TEST_ARRAY_SIZE))
		elog(ERROR, "pg_lfind32() did not find existing element");

	if (pg_lfind32(4, test_array, TEST_ARRAY_SIZE))
		elog(ERROR, "pg_lfind32() found nonexistent element");

	PG_RETURN_VOID();
}
