1// SPDX-License-Identifier: GPL-2.0
  2#include <malloc.h>
  3#include <stdlib.h>
  4#include <string.h>
  5#include "utils.h"
  6
  7#define SIZE 256
  8#define ITERATIONS 10000
  9
 10int test_memcmp(const void *s1, const void *s2, size_t n);
 11
 12/* test all offsets and lengths */
 13static void test_one(char *s1, char *s2)
 14{
 15	unsigned long offset, size;
 16
 17	for (offset = 0; offset < SIZE; offset++) {
 18		for (size = 0; size < (SIZE-offset); size++) {
 19			int x, y;
 20			unsigned long i;
 21
 22			y = memcmp(s1+offset, s2+offset, size);
 23			x = test_memcmp(s1+offset, s2+offset, size);
 24
 25			if (((x ^ y) < 0) &&	/* Trick to compare sign */
 26				((x | y) != 0)) { /* check for zero */
 27				printf("memcmp returned %d, should have returned %d (offset %ld size %ld)\n", x, y, offset, size);
 28
 29				for (i = offset; i < offset+size; i++)
 30					printf("%02x ", s1[i]);
 31				printf("\n");
 32
 33				for (i = offset; i < offset+size; i++)
 34					printf("%02x ", s2[i]);
 35				printf("\n");
 36				abort();
 37			}
 38		}
 39	}
 40}
 41
 42static int testcase(void)
 43{
 44	char *s1;
 45	char *s2;
 46	unsigned long i;
 47
 48	s1 = memalign(128, SIZE);
 49	if (!s1) {
 50		perror("memalign");
 51		exit(1);
 52	}
 53
 54	s2 = memalign(128, SIZE);
 55	if (!s2) {
 56		perror("memalign");
 57		exit(1);
 58	}
 59
 60	srandom(1);
 61
 62	for (i = 0; i < ITERATIONS; i++) {
 63		unsigned long j;
 64		unsigned long change;
 65
 66		for (j = 0; j < SIZE; j++)
 67			s1[j] = random();
 68
 69		memcpy(s2, s1, SIZE);
 70
 71		/* change one byte */
 72		change = random() % SIZE;
 73		s2[change] = random() & 0xff;
 74
 75		test_one(s1, s2);
 76	}
 77
 78	srandom(1);
 79
 80	for (i = 0; i < ITERATIONS; i++) {
 81		unsigned long j;
 82		unsigned long change;
 83
 84		for (j = 0; j < SIZE; j++)
 85			s1[j] = random();
 86
 87		memcpy(s2, s1, SIZE);
 88
 89		/* change multiple bytes, 1/8 of total */
 90		for (j = 0; j < SIZE / 8; j++) {
 91			change = random() % SIZE;
 92			s2[change] = random() & 0xff;
 93		}
 94
 95		test_one(s1, s2);
 96	}
 97
 98	return 0;
 99}
100
101int main(void)
102{
103	return test_harness(testcase, "memcmp");
104}