Re: [PATCH v3 4/4] selftests/nolibc: Add tests for strlcat() and strlcpy()

["Thomas Weißschuh" <linux@weissschuh.net>]

+ Shuah and Paul, please see below.

So I picked this up and it got picked up by Shuah, but...

On 2024-02-18 16:51:06+0000, Rodrigo Campos wrote:
> I've verified that the tests matches libbsd's strlcat()/strlcpy()
> implementation.
> 
> Please note that as strlcat()/strlcpy() are not part of the libc, the
> tests are only compiled when using nolibc.
> 
> Signed-off-by: Rodrigo Campos <rodrigo@sdfg.com.ar>
> ---
>  tools/testing/selftests/nolibc/nolibc-test.c | 40 ++++++++++++++++++++
>  1 file changed, 40 insertions(+)
> 
> diff --git a/tools/testing/selftests/nolibc/nolibc-test.c b/tools/testing/selftests/nolibc/nolibc-test.c
> index 6ba4f8275ac4..d373fc14706c 100644
> --- a/tools/testing/selftests/nolibc/nolibc-test.c
> +++ b/tools/testing/selftests/nolibc/nolibc-test.c
> @@ -600,6 +600,25 @@ int expect_strne(const char *expr, int llen, const char *cmp)
>  	return ret;
>  }
>  
> +#define EXPECT_STRBUFEQ(cond, expr, buf, val, cmp)				\
> +	do { if (!(cond)) result(llen, SKIPPED); else ret += expect_str_buf_eq(expr, buf, val, llen, cmp); } while (0)
> +
> +static __attribute__((unused))
> +int expect_str_buf_eq(size_t expr, const char *buf, size_t val, int llen, const char *cmp)
> +{
> +	llen += printf(" = %lu <%s> ", expr, buf);

This introduces a compiler warning on 32bit:

    i386-linux-gcc -Os -fno-ident -fno-asynchronous-unwind-tables -std=c89 -W -Wall -Wextra -fno-stack-protector -m32 -mstack-protector-guard=global -fstack-protector-all  -o nolibc-test \
      -nostdlib -nostdinc -static -Isysroot/i386/include nolibc-test.c nolibc-test-linkage.c -lgcc
    nolibc-test.c: In function 'expect_str_buf_eq':
    nolibc-test.c:610:30: error: format '%lu' expects argument of type 'long unsigned int', but argument 2 has type 'size_t' {aka 'unsigned int'} [-Werror=format=]
      610 |         llen += printf(" = %lu <%s> ", expr, buf);
          |                            ~~^         ~~~~
          |                              |         |
          |                              |         size_t {aka unsigned int}
          |                              long unsigned int
          |                            %u


It is easy enough to fix through a cast to "unsigned long".

The original patch was already sent to Shuah and included in -next.

Shuah, Paul:

I'd like to rewrite the offending commit instead of having a fixup commit.
As it seems to me the original patch would only go into 6.10 anyways.

Any objections?

Notes to self:

* Add flag to run-tests.sh to use -Werror
* Implement "%zu" in nolibc printf()

> +	if (strcmp(buf, cmp) != 0) {
> +		result(llen, FAIL);
> +		return 1;
> +	}
> +	if (expr != val) {
> +		result(llen, FAIL);
> +		return 1;
> +	}
> +
> +	result(llen, OK);
> +	return 0;
> +}

> [..]