1 // SPDX-License-Identifier: GPL-2.0
3 * Kernel module for testing 'strcat' family of functions.
6 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
8 #include <kunit/test.h>
9 #include <linux/string.h>
11 static volatile int unconst
;
13 static void strcat_test(struct kunit
*test
)
17 /* Destination is terminated. */
18 memset(dest
, 0, sizeof(dest
));
19 KUNIT_EXPECT_EQ(test
, strlen(dest
), 0);
20 /* Empty copy does nothing. */
21 KUNIT_EXPECT_TRUE(test
, strcat(dest
, "") == dest
);
22 KUNIT_EXPECT_STREQ(test
, dest
, "");
23 /* 4 characters copied in, stops at %NUL. */
24 KUNIT_EXPECT_TRUE(test
, strcat(dest
, "four\000123") == dest
);
25 KUNIT_EXPECT_STREQ(test
, dest
, "four");
26 KUNIT_EXPECT_EQ(test
, dest
[5], '\0');
27 /* 2 more characters copied in okay. */
28 KUNIT_EXPECT_TRUE(test
, strcat(dest
, "AB") == dest
);
29 KUNIT_EXPECT_STREQ(test
, dest
, "fourAB");
32 static void strncat_test(struct kunit
*test
)
36 /* Destination is terminated. */
37 memset(dest
, 0, sizeof(dest
));
38 KUNIT_EXPECT_EQ(test
, strlen(dest
), 0);
39 /* Empty copy of size 0 does nothing. */
40 KUNIT_EXPECT_TRUE(test
, strncat(dest
, "", 0 + unconst
) == dest
);
41 KUNIT_EXPECT_STREQ(test
, dest
, "");
42 /* Empty copy of size 1 does nothing too. */
43 KUNIT_EXPECT_TRUE(test
, strncat(dest
, "", 1 + unconst
) == dest
);
44 KUNIT_EXPECT_STREQ(test
, dest
, "");
45 /* Copy of max 0 characters should do nothing. */
46 KUNIT_EXPECT_TRUE(test
, strncat(dest
, "asdf", 0 + unconst
) == dest
);
47 KUNIT_EXPECT_STREQ(test
, dest
, "");
49 /* 4 characters copied in, even if max is 8. */
50 KUNIT_EXPECT_TRUE(test
, strncat(dest
, "four\000123", 8 + unconst
) == dest
);
51 KUNIT_EXPECT_STREQ(test
, dest
, "four");
52 KUNIT_EXPECT_EQ(test
, dest
[5], '\0');
53 KUNIT_EXPECT_EQ(test
, dest
[6], '\0');
54 /* 2 characters copied in okay, 2 ignored. */
55 KUNIT_EXPECT_TRUE(test
, strncat(dest
, "ABCD", 2 + unconst
) == dest
);
56 KUNIT_EXPECT_STREQ(test
, dest
, "fourAB");
59 static void strlcat_test(struct kunit
*test
)
62 int len
= sizeof(dest
) + unconst
;
64 /* Destination is terminated. */
65 KUNIT_EXPECT_EQ(test
, strlen(dest
), 0);
66 /* Empty copy is size 0. */
67 KUNIT_EXPECT_EQ(test
, strlcat(dest
, "", len
), 0);
68 KUNIT_EXPECT_STREQ(test
, dest
, "");
69 /* Size 1 should keep buffer terminated, report size of source only. */
70 KUNIT_EXPECT_EQ(test
, strlcat(dest
, "four", 1 + unconst
), 4);
71 KUNIT_EXPECT_STREQ(test
, dest
, "");
73 /* 4 characters copied in. */
74 KUNIT_EXPECT_EQ(test
, strlcat(dest
, "four", len
), 4);
75 KUNIT_EXPECT_STREQ(test
, dest
, "four");
76 /* 2 characters copied in okay, gets to 6 total. */
77 KUNIT_EXPECT_EQ(test
, strlcat(dest
, "AB", len
), 6);
78 KUNIT_EXPECT_STREQ(test
, dest
, "fourAB");
79 /* 2 characters ignored if max size (7) reached. */
80 KUNIT_EXPECT_EQ(test
, strlcat(dest
, "CD", 7 + unconst
), 8);
81 KUNIT_EXPECT_STREQ(test
, dest
, "fourAB");
82 /* 1 of 2 characters skipped, now at true max size. */
83 KUNIT_EXPECT_EQ(test
, strlcat(dest
, "EFG", len
), 9);
84 KUNIT_EXPECT_STREQ(test
, dest
, "fourABE");
85 /* Everything else ignored, now at full size. */
86 KUNIT_EXPECT_EQ(test
, strlcat(dest
, "1234", len
), 11);
87 KUNIT_EXPECT_STREQ(test
, dest
, "fourABE");
90 static struct kunit_case strcat_test_cases
[] = {
91 KUNIT_CASE(strcat_test
),
92 KUNIT_CASE(strncat_test
),
93 KUNIT_CASE(strlcat_test
),
97 static struct kunit_suite strcat_test_suite
= {
99 .test_cases
= strcat_test_cases
,
102 kunit_test_suite(strcat_test_suite
);
104 MODULE_LICENSE("GPL");