1/* Test the strlcat function.
2 Copyright (C) 2023-2024 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
4
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Lesser General Public
7 License as published by the Free Software Foundation; either
8 version 2.1 of the License, or (at your option) any later version.
9
10 The GNU C Library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Lesser General Public License for more details.
14
15 You should have received a copy of the GNU Lesser General Public
16 License along with the GNU C Library; if not, see
17 <https://www.gnu.org/licenses/>. */
18
19#include <string.h>
20#include <stdlib.h>
21#include <stdio.h>
22#include <support/check.h>
23
24static int
25do_test (void)
26{
27 struct {
28 char buf1[16];
29 char buf2[16];
30 } s;
31
32 /* Nothing is written to the destination if its size is 0. */
33 memset (&s, '@', sizeof (s));
34 TEST_COMPARE (strlcat (s.buf1, "", 0), 0);
35 TEST_COMPARE_BLOB (&s, sizeof (s), "@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@", 32);
36 TEST_COMPARE (strlcat (s.buf1, "Hello!", 0), 6);
37 TEST_COMPARE_BLOB (&s, sizeof (s), "@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@", 32);
38
39 /* No bytes are are modified in the target buffer if the source
40 string is short enough. */
41 memset (&s, '@', sizeof (s));
42 strcpy (s.buf1, "He");
43 TEST_COMPARE (strlcat (s.buf1, "llo!", sizeof (s.buf1)), 6);
44 TEST_COMPARE_BLOB (&s, sizeof (s), "Hello!\0@@@@@@@@@@@@@@@@@@@@@@@@@", 32);
45
46 /* A source string which fits exactly into the destination buffer is
47 not truncated. */
48 memset (&s, '@', sizeof (s));
49 strcpy (s.buf1, "H");
50 TEST_COMPARE (strlcat (s.buf1, "ello, world!!!", sizeof (s.buf1)), 15);
51 TEST_COMPARE_BLOB (&s, sizeof (s),
52 "Hello, world!!!\0@@@@@@@@@@@@@@@@@@@@@@@@@", 32);
53
54 /* A source string one character longer than the destination buffer
55 is truncated by one character. The total length is returned. */
56 memset (&s, '@', sizeof (s));
57 strcpy (s.buf1, "Hello");
58 TEST_COMPARE (strlcat (s.buf1, ", world!!!!", sizeof (s.buf1)), 16);
59 TEST_COMPARE_BLOB (&s, sizeof (s),
60 "Hello, world!!!\0@@@@@@@@@@@@@@@@@@@@@@@@@", 32);
61
62 /* An even longer source string is truncated as well, and the total
63 length is returned. */
64 memset (&s, '@', sizeof (s));
65 strcpy (s.buf1, "Hello,");
66 TEST_COMPARE (strlcat (s.buf1, " world!!!!!!!!", sizeof (s.buf1)), 20);
67 TEST_COMPARE_BLOB (&s, sizeof (s),
68 "Hello, world!!!\0@@@@@@@@@@@@@@@@@@@@@@@@@", 32);
69
70 /* A destination string which is not NUL-terminated does not result
71 in any changes to the buffer. */
72 memset (&s, '@', sizeof (s));
73 memset (s.buf1, '$', sizeof (s.buf1));
74 TEST_COMPARE (strlcat (s.buf1, "", sizeof (s.buf1)), 16);
75 TEST_COMPARE_BLOB (&s, sizeof (s), "$$$$$$$$$$$$$$$$@@@@@@@@@@@@@@@@", 32);
76 TEST_COMPARE (strlcat (s.buf1, "Hello!", sizeof (s.buf1)), 22);
77 TEST_COMPARE_BLOB (&s, sizeof (s), "$$$$$$$$$$$$$$$$@@@@@@@@@@@@@@@@", 32);
78 TEST_COMPARE (strlcat (s.buf1, "Hello, world!!!!!!!!", sizeof (s.buf1)), 36);
79 TEST_COMPARE_BLOB (&s, sizeof (s), "$$$$$$$$$$$$$$$$@@@@@@@@@@@@@@@@", 32);
80
81 return 0;
82}
83
84#include <support/test-driver.c>
85

source code of glibc/string/tst-strlcat.c