[LTP] [PATCH v3 1/3] API: TST_EXP_FAIL: Allow passing when errno is not checked

[Cyril Hrubis]

Hi!
> Judging by the existing usage of TST_EXP_FAIL(..., 0, ...) in
> finit_module02. We want to pass if errno == 0 otherwise the test will
> not return a result.

This is actually not true, we do not pass 0 to TST_EXP_FAIL() in
finit_module() at all. The places that are not initialized in the
structure are initialized at runtime based on the kernel version. I do
not think that we even pass 0 to TST_EXP_FAIL*() as an errno anywhere,
but I haven't really checked all the callers.

> This is also less surprising than giving errno == 0 a dual
> meaning.

But I do agree that the current if (ERRNO) branch is confusing. I would
be for dropping the if (ERRNO) and checking the TST_ERR against ERRNO
unconditionally.

Also note that the TEST() macro clears errno, so if a syscall fails but
does not report any error TST_ERR will end up 0 either way so there is
no need for having special handling for 0.

> This also changes the trailing '\' indentation to tabs. However this
> is correct and the rest of the file is wrong.
> 
> Signed-off-by: Richard Palethorpe <rpalethorpe@suse.com>
> ---
> 
> V3:
> * Add fix for TST_EXP_FAIL which prevented the test from
>   passing on a non buggy system.
> * TCONF but continue on non 32-bit compat mode
> * Add Fixes trailer
> 
> V2:
> * Add mising lapi header
> 
>  include/tst_test_macros.h | 20 +++++++++-----------
>  1 file changed, 9 insertions(+), 11 deletions(-)
> 
> diff --git a/include/tst_test_macros.h b/include/tst_test_macros.h
> index 41886fbbc..4c1df58ff 100644
> --- a/include/tst_test_macros.h
> +++ b/include/tst_test_macros.h
> @@ -137,17 +137,15 @@ extern void *TST_RET_PTR;
>  			break;                                                 \
>  		}                                                              \
>  		                                                               \
> -		if (ERRNO) {                                                   \
> -			if (TST_ERR == ERRNO) {                                \
> -				TST_MSG_(TPASS | TTERRNO, " ",                 \
> -				         #SCALL, ##__VA_ARGS__);               \
> -				TST_PASS = 1;                                  \
> -			} else {                                               \
> -				TST_MSGP_(TFAIL | TTERRNO, " expected %s",     \
> -				          tst_strerrno(ERRNO),                 \
> -				          #SCALL, ##__VA_ARGS__);              \
> -			}                                                      \
> -		}                                                              \
> +		if (!ERRNO || TST_ERR == ERRNO) {			\
> +			TST_MSG_(TPASS | TTERRNO, " ",			\
> +				 #SCALL, ##__VA_ARGS__);		\
> +			TST_PASS = 1;					\
> +		} else {						\
> +			TST_MSGP_(TFAIL | TTERRNO, " expected %s",	\
> +				  tst_strerrno(ERRNO),			\
> +				  #SCALL, ##__VA_ARGS__);		\
> +		}							\
>  	} while (0)
>  
>  #define TST_EXP_FAIL(SCALL, ERRNO, ...) TST_EXP_FAIL_(TST_RET == 0, SCALL, ERRNO, __VA_ARGS__)
> -- 
> 2.31.1
> 
> 
> -- 
> Mailing list info: https://lists.linux.it/listinfo/ltp

-- 
Cyril Hrubis
chrubis@suse.cz