Re: [RFC PATCH 4/4] tools/nolibc: add tests for the integer limits in stdint.h

From: Thomas Weißschuh
Date: Sun Feb 19 2023 - 14:04:18 EST

On Sun, Feb 19, 2023 at 07:51:33PM +0100, Willy Tarreau wrote:
> From: Vincent Dagonneau <v@xxxxxx>
>
> This commit adds tests for the limits added in a previous commit. The
> limits are defined in decimal in stdint.h and as hexadecimal in the
> tests (e.g. 0x7f = 127 or 0x80 = -128). Hopefully it catches some o the
> most egregious mistakes.
>
> Signed-off-by: Vincent Dagonneau <v@xxxxxx>
> [wt: rely on the compiler-provided __SIZEOF_LONG__ to decide what values
> to expect, and detect its miss to avoid reporting false errors]
> Signed-off-by: Willy Tarreau <w@xxxxxx>
> ---
> tools/testing/selftests/nolibc/nolibc-test.c | 45 +++++++++++++++++++-
> 1 file changed, 44 insertions(+), 1 deletion(-)
>
> diff --git a/tools/testing/selftests/nolibc/nolibc-test.c b/tools/testing/selftests/nolibc/nolibc-test.c
> index 882140508d56..290249d6da30 100644
> --- a/tools/testing/selftests/nolibc/nolibc-test.c
> +++ b/tools/testing/selftests/nolibc/nolibc-test.c
> @@ -561,7 +561,50 @@ int run_syscall(int min, int max)
> CASE_TEST(waitpid_child); EXPECT_SYSER(1, waitpid(getpid(), &tmp, WNOHANG), -1, ECHILD); break;
> CASE_TEST(write_badf); EXPECT_SYSER(1, write(-1, &tmp, 1), -1, EBADF); break;
> CASE_TEST(write_zero); EXPECT_SYSZR(1, write(1, &tmp, 0)); break;
> - case __LINE__:
> + CASE_TEST(limit_int8_max); EXPECT_EQ(1, INT8_MAX, (int8_t) 0x7f); break;
> + CASE_TEST(limit_int8_min); EXPECT_EQ(1, INT8_MIN, (int8_t) 0x80); break;
> + CASE_TEST(limit_uint8_max); EXPECT_EQ(1, UINT8_MAX, (uint8_t) 0xff); break;
> + CASE_TEST(limit_int16_max); EXPECT_EQ(1, INT16_MAX, (int16_t) 0x7fff); break;
> + CASE_TEST(limit_int16_min); EXPECT_EQ(1, INT16_MIN, (int16_t) 0x8000); break;
> + CASE_TEST(limit_uint16_max); EXPECT_EQ(1, UINT16_MAX, (uint16_t) 0xffff); break;
> + CASE_TEST(limit_int32_max); EXPECT_EQ(1, INT32_MAX, (int32_t) 0x7fffffff); break;
> + CASE_TEST(limit_int32_min); EXPECT_EQ(1, INT32_MIN, (int32_t) 0x80000000); break;
> + CASE_TEST(limit_uint32_max); EXPECT_EQ(1, UINT32_MAX, (uint32_t) 0xffffffff); break;
> + CASE_TEST(limit_int64_max); EXPECT_EQ(1, INT64_MAX, (int64_t) 0x7fffffffffffffff); break;
> + CASE_TEST(limit_int64_min); EXPECT_EQ(1, INT64_MIN, (int64_t) 0x8000000000000000); break;
> + CASE_TEST(limit_uint64_max); EXPECT_EQ(1, UINT64_MAX, (uint64_t) 0xffffffffffffffff); break;
> + CASE_TEST(limit_int_least8_max); EXPECT_EQ(1, INT_LEAST8_MAX, (int_least8_t) 0x7f); break;
> + CASE_TEST(limit_int_least8_min); EXPECT_EQ(1, INT_LEAST8_MIN, (int_least8_t) 0x80); break;
> + CASE_TEST(limit_uint_least8_max); EXPECT_EQ(1, UINT_LEAST8_MAX, (uint_least8_t) 0xff); break;
> + CASE_TEST(limit_int_least16_max); EXPECT_EQ(1, INT_LEAST16_MAX, (int_least16_t) 0x7fff); break;
> + CASE_TEST(limit_int_least16_min); EXPECT_EQ(1, INT_LEAST16_MIN, (int_least16_t) 0x8000); break;
> + CASE_TEST(limit_uint_least16_max); EXPECT_EQ(1, UINT_LEAST16_MAX, (uint_least16_t) 0xffff); break;
> + CASE_TEST(limit_int_least32_max); EXPECT_EQ(1, INT_LEAST32_MAX, (int_least32_t) 0x7fffffff); break;
> + CASE_TEST(limit_int_least32_min); EXPECT_EQ(1, INT_LEAST32_MIN, (int_least32_t) 0x80000000); break;
> + CASE_TEST(limit_uint_least32_max); EXPECT_EQ(1, UINT_LEAST32_MAX, (uint_least32_t) 0xffffffffU); break;
> +#if __SIZEOF_LONG__ == 8
> + CASE_TEST(limit_int_least64_max); EXPECT_EQ(1, INT_LEAST64_MAX, (int_least64_t) 0x7fffffffffffffffLL); break;
> + CASE_TEST(limit_int_least64_min); EXPECT_EQ(1, INT_LEAST64_MIN, (int_least64_t) 0x8000000000000000LL); break;
> + CASE_TEST(limit_uint_least64_max); EXPECT_EQ(1, UINT_LEAST64_MAX, (uint_least64_t) 0xffffffffffffffffULL); break;

int64 types are also defined for 32bit platforms, but the tests are only
ran for 64bits. Is this intentional?

> + CASE_TEST(limit_intptr_min); EXPECT_EQ(1, INTPTR_MIN, (intptr_t) 0x8000000000000000LL); break;
> + CASE_TEST(limit_intptr_max); EXPECT_EQ(1, INTPTR_MAX, (intptr_t) 0x7fffffffffffffffLL); break;
> + CASE_TEST(limit_uintptr_max); EXPECT_EQ(1, UINTPTR_MAX, (uintptr_t) 0xffffffffffffffffULL); break;
> + CASE_TEST(limit_ptrdiff_min); EXPECT_EQ(1, PTRDIFF_MIN, (ptrdiff_t) 0x8000000000000000LL); break;
> + CASE_TEST(limit_ptrdiff_max); EXPECT_EQ(1, PTRDIFF_MAX, (ptrdiff_t) 0x7fffffffffffffffLL); break;
> + CASE_TEST(limit_size_max); EXPECT_EQ(1, SIZE_MAX, (size_t) 0xffffffffffffffffULL); break;
> +#elif __SIZEOF_LONG__ == 4
> + CASE_TEST(limit_intptr_min); EXPECT_EQ(1, INTPTR_MIN, (intptr_t) 0x80000000); break;
> + CASE_TEST(limit_intptr_max); EXPECT_EQ(1, INTPTR_MAX, (intptr_t) 0x7fffffff); break;
> + CASE_TEST(limit_uintptr_max); EXPECT_EQ(1, UINTPTR_MAX, (uintptr_t) 0xffffffffU); break;
> + CASE_TEST(limit_ptrdiff_min); EXPECT_EQ(1, PTRDIFF_MIN, (ptrdiff_t) 0x80000000); break;
> + CASE_TEST(limit_ptrdiff_max); EXPECT_EQ(1, PTRDIFF_MAX, (ptrdiff_t) 0x7fffffff); break;
> + CASE_TEST(limit_ptrdiff_min); EXPECT_EQ(1, PTRDIFF_MIN, (ptrdiff_t) 0x80000000); break;
> + CASE_TEST(limit_ptrdiff_max); EXPECT_EQ(1, PTRDIFF_MAX, (ptrdiff_t) 0x7fffffff); break;

ptrdiff tests are duplicate.

> + CASE_TEST(limit_size_max); EXPECT_EQ(1, SIZE_MAX, (size_t) 0xffffffffU); break;
> +#else
> +# warning "__SIZEOF_LONG__ is undefined"

Why not #error?

> +#endif /* __WORDSIZE == 64 */

#endif comment is now incorrect

> + case __LINE__:

The "case" should be further left, no?

> return ret; /* must be last */
> /* note: do not set any defaults so as to permit holes above */
> }
> --
> 2.35.3
>