1/*-
2 * Copyright (c) 2016 Jilles Tjoelker <jilles@FreeBSD.org>
3 * Copyright (c) 2023 The FreeBSD Foundation
4 * All rights reserved.
5 *
6 * Portions of this software were developed by Robert Clausecker
7 * <fuz@FreeBSD.org> under sponsorship from the FreeBSD Foundation.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 * 1. Redistributions of source code must retain the above copyright
13 *    notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 *    notice, this list of conditions and the following disclaimer in the
16 *    documentation and/or other materials provided with the distribution.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28 * SUCH DAMAGE.
29 */
30
31#include <assert.h>
32#include <dlfcn.h>
33#include <stdio.h>
34#include <stdlib.h>
35#include <string.h>
36
37#include <atf-c.h>
38
39#ifndef MEMCMP
40#define MEMCMP memcmp
41#endif
42
43/*
44 * On FreeBSD we demand that memcmp returns the difference between the
45 * characters at the first site of mismatch.  However, ISO/IEC 9899:1990
46 * only specifies that a number greater than, equal to, or less than
47 * zero shall be returned.  If a unit test for this less strict
48 * behaviour is desired, define RES(x) to be (((x) > 0) - ((x) < 0)).
49 */
50#ifndef RES
51#define RES(x) (x)
52#endif
53
54static int (*memcmp_fn)(const void *, const void *, size_t);
55
56static void
57check_memcmp(const char *a, const char *b, size_t len, int expected)
58{
59	int got;
60
61	got = memcmp_fn(a, b, len);
62	ATF_CHECK_EQ_MSG(RES(expected), RES(got),
63	    "%s(%p, %p, %zu) gave %d, but wanted %d",
64	    __XSTRING(MEMCMP), a, b, len, got, expected);
65}
66
67ATF_TC_WITHOUT_HEAD(zero);
68ATF_TC_BODY(zero, tc)
69{
70
71	check_memcmp("a", "b", 0, 0);
72	check_memcmp("", "", 0, 0);
73}
74
75ATF_TC_WITHOUT_HEAD(eq);
76ATF_TC_BODY(eq, tc)
77{
78	unsigned char data1[256], data2[256];
79	int i;
80
81	for (i = 0; i < 256; i++)
82		data1[i] = data2[i] = i ^ 0x55;
83	for (i = 1; i < 256; i++)
84		check_memcmp(data1, data2, i, 0);
85	for (i = 1; i < 256; i++)
86		check_memcmp(data1 + i, data2 + i, 256 - i, 0);
87}
88
89ATF_TC_WITHOUT_HEAD(neq);
90ATF_TC_BODY(neq, tc)
91{
92	unsigned char data1[256], data2[256];
93	int i;
94
95	for (i = 0; i < 256; i++) {
96		data1[i] = i;
97		data2[i] = i ^ 0x55;
98	}
99	for (i = 1; i < 256; i++)
100		check_memcmp(data1, data2, i, -0x55);
101	for (i = 1; i < 256; i++)
102		check_memcmp(data1 + i, data2 + i, 256 - i, i - (i ^ 0x55));
103}
104
105ATF_TC_WITHOUT_HEAD(diff);
106ATF_TC_BODY(diff, tc)
107{
108	unsigned char data1[256], data2[256];
109	int i;
110
111	memset(data1, 'a', sizeof(data1));
112	memset(data2, 'a', sizeof(data2));
113	data1[128] = 255;
114	data2[128] = 0;
115	for (i = 1; i < 66; i++) {
116		check_memcmp(data1 + 128, data2 + 128, i, 255);
117		check_memcmp(data2 + 128, data1 + 128, i, -255);
118		check_memcmp(data1 + 129 - i, data2 + 129 - i, i, 255);
119		check_memcmp(data2 + 129 - i, data1 + 129 - i, i, -255);
120		check_memcmp(data1 + 129 - i, data2 + 129 - i, i * 2, 255);
121		check_memcmp(data2 + 129 - i, data1 + 129 - i, i * 2, -255);
122	}
123	data1[128] = 'c';
124	data2[128] = 'e';
125	for (i = 1; i < 66; i++) {
126		check_memcmp(data1 + 128, data2 + 128, i, -2);
127		check_memcmp(data2 + 128, data1 + 128, i, 2);
128		check_memcmp(data1 + 129 - i, data2 + 129 - i, i, -2);
129		check_memcmp(data2 + 129 - i, data1 + 129 - i, i, 2);
130		check_memcmp(data1 + 129 - i, data2 + 129 - i, i * 2, -2);
131		check_memcmp(data2 + 129 - i, data1 + 129 - i, i * 2, 2);
132	}
133	memset(data1 + 129, 'A', sizeof(data1) - 129);
134	memset(data2 + 129, 'Z', sizeof(data2) - 129);
135	for (i = 1; i < 66; i++) {
136		check_memcmp(data1 + 128, data2 + 128, i, -2);
137		check_memcmp(data2 + 128, data1 + 128, i, 2);
138		check_memcmp(data1 + 129 - i, data2 + 129 - i, i, -2);
139		check_memcmp(data2 + 129 - i, data1 + 129 - i, i, 2);
140		check_memcmp(data1 + 129 - i, data2 + 129 - i, i * 2, -2);
141		check_memcmp(data2 + 129 - i, data1 + 129 - i, i * 2, 2);
142	}
143}
144
145ATF_TP_ADD_TCS(tp)
146{
147	void *dl_handle;
148
149	dl_handle = dlopen(NULL, RTLD_LAZY);
150	memcmp_fn = dlsym(dl_handle, "test_" __XSTRING(MEMCMP));
151	if (memcmp_fn == NULL)
152		memcmp_fn = MEMCMP;
153
154	ATF_TP_ADD_TC(tp, zero);
155	ATF_TP_ADD_TC(tp, eq);
156	ATF_TP_ADD_TC(tp, neq);
157	ATF_TP_ADD_TC(tp, diff);
158
159	return (atf_no_error());
160}
161