lib/test_string.c: add some testcases for strchr and strnchr

Make sure that the trailing NUL is considered part of the string and can
be found.

Link: http://lkml.kernel.org/r/20190506124634.6807-4-peda@axentia.se
Signed-off-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Peter Rosin 2019-07-16 16:27:21 -07:00 committed by Linus Torvalds
parent 33d6e0ff68
commit d1a5dc5e6a

View File

@ -112,6 +112,73 @@ static __init int memset64_selftest(void)
return 0;
}
static __init int strchr_selftest(void)
{
const char *test_string = "abcdefghijkl";
const char *empty_string = "";
char *result;
int i;
for (i = 0; i < strlen(test_string) + 1; i++) {
result = strchr(test_string, test_string[i]);
if (result - test_string != i)
return i + 'a';
}
result = strchr(empty_string, '\0');
if (result != empty_string)
return 0x101;
result = strchr(empty_string, 'a');
if (result)
return 0x102;
result = strchr(test_string, 'z');
if (result)
return 0x103;
return 0;
}
static __init int strnchr_selftest(void)
{
const char *test_string = "abcdefghijkl";
const char *empty_string = "";
char *result;
int i, j;
for (i = 0; i < strlen(test_string) + 1; i++) {
for (j = 0; j < strlen(test_string) + 2; j++) {
result = strnchr(test_string, j, test_string[i]);
if (j <= i) {
if (!result)
continue;
return ((i + 'a') << 8) | j;
}
if (result - test_string != i)
return ((i + 'a') << 8) | j;
}
}
result = strnchr(empty_string, 0, '\0');
if (result)
return 0x10001;
result = strnchr(empty_string, 1, '\0');
if (result != empty_string)
return 0x10002;
result = strnchr(empty_string, 1, 'a');
if (result)
return 0x10003;
result = strnchr(NULL, 0, '\0');
if (result)
return 0x10004;
return 0;
}
static __init int string_selftest_init(void)
{
int test, subtest;
@ -131,6 +198,16 @@ static __init int string_selftest_init(void)
if (subtest)
goto fail;
test = 4;
subtest = strchr_selftest();
if (subtest)
goto fail;
test = 5;
subtest = strnchr_selftest();
if (subtest)
goto fail;
pr_info("String selftests succeeded\n");
return 0;
fail: