On Thu, Jun 01, 2023 at 05:02:50PM -0500, Eric Blake wrote:
> We have quite a few undertested and underdocumented integer parsing
> corner cases. To ensure that any changes we make in the code are
> intentional rather than accidental semantic changes, it is time to add
> more unit tests of existing behavior.
>
> static void test_qemu_strtol_overflow(void)
> {
> - const char *str = "99999999999999999999999999999999999999999999";
> + const char *str;
> + const char *endptr;
> + long res;
> + int err;
> +
> + /* 1 more than LONG_MAX */
> + str = LONG_MAX == INT_MAX ? "2147483648" : "9223372036854775808";
> + endptr = "somewhere";
> + res = 999;
> + err = qemu_strtol(str, &endptr, 0, &res);
> + g_assert_cmpint(err, ==, -ERANGE);
> + g_assert_cmpint(res, ==, LONG_MAX);
> + g_assert_true(endptr == str + strlen(str));
> +
> + if (LONG_MAX == INT_MAX) {
> + str = "0xffffffff00000001"; /* ULLONG_MAX - UINT_MAX + 1 (not 1) */
> + endptr = "somewhere";
> + res = 999;
> + err = qemu_strtol(str, &endptr, 0, &res);
> + g_assert_cmpint(err, ==, -ERANGE);
> + g_assert_cmpint(res, ==, LONG_MIN);
> + g_assert_true(endptr == str + strlen(str));
> + }
Copy-paste failure, but only visible on platforms like mingw where
long is 32-bits; I had copied this...
>
> static void test_qemu_strtol_underflow(void)
> {
> - const char *str = "-99999999999999999999999999999999999999999999";
> - char f = 'X';
> - const char *endptr = &f;
> - long res = 999;
> + const char *str;
> + const char *endptr;
> + long res;
> int err;
>
> + /* 1 less than LONG_MIN */
> + str = LONG_MIN == INT_MIN ? "-2147483649" : "-9223372036854775809";
> + endptr = "somewhere";
> + res = 999;
> err = qemu_strtol(str, &endptr, 0, &res);
> + g_assert_cmpint(err, ==, -ERANGE);
> + g_assert_cmpint(res, ==, LONG_MIN);
> + g_assert_true(endptr == str + strlen(str));
>
> + if (LONG_MAX == INT_MAX) {
> + str = "-18446744073709551615"; /* -UINT64_MAX (not 1) */
> + endptr = "somewhere";
> + res = 999;
> + err = qemu_strtol(str, &endptr, 0, &res);
> + g_assert_cmpint(err, ==, -ERANGE);
> + g_assert_cmpint(res, ==, LONG_MIN);
> + g_assert_true(endptr == str + strlen(str));
> + }
...from here, but failed to s/MIN/MAX/ when dealing with the changed
sign. Yay for CI catching it.
--
Eric Blake, Principal Software Engineer
Red Hat, Inc. +1-919-301-3266
Virtualization: qemu.org | libvirt.org
