[LTP] [PATCH v4 2/4] syscalls: lchown01: Convert to new API

[Ricardo B. Marlière]

On Thu Aug 28, 2025 at 8:28 AM -03, Cyril Hrubis wrote:
> Hi!
>> -struct test_case_t {
>> +static struct test_case_t {
>>  	char *desc;
>>  	uid_t user_id;
>>  	gid_t group_id;
>> +} test_cases[] = {
>> +	{ "Change Owner/Group ids", 700, 701 },
>> +	{ "Change Owner id only", 702, 0 },
>> +	{ "Change Owner/Group ids", 703, 701 },
>> +	{ "Change Group id only", 0, 704 },
>> +	{ "Change Group/Group ids", 703, 705 },
>> +	{ "Change none", 0, 0 },
>>  };
>>  
>> -static struct test_case_t test_cases[] = {
>> -	{"Change Owner/Group ids", 700, 701},
>> -	{"Change Owner id only", 702, -1},
>> -	{"Change Owner/Group ids", 703, 701},
>> -	{"Change Group id only", -1, 704},
>> -	{"Change Group/Group ids", 703, 705},
>> -	{"Change none", -1, -1},
>> -	{NULL, 0, 0}
>> -};
>
> This actually changes what the test does. To cite manual page:
>
> "If the owner or group is specified as -1, then that ID is not changed."
>
> The -1 values there were correct, all we need to do in case we have -1
> in there is to lstat() the file before lchonw() and use that value for
> the check.
>
>
>> -	cleanup();
>> -	tst_exit();
>> +	struct test_case_t *tc = &test_cases[i];
>> +	uid_t user_id = tc->user_id;
>> +	gid_t group_id = tc->group_id;
>> +
>> +	tst_res(TINFO, "%s", tc->desc);
>> +	SAFE_LCHOWN(SFILE, user_id, group_id);
>> +	SAFE_LSTAT(SFILE, &stat_buf);
>> +	TST_EXP_EQ_LI(stat_buf.st_uid, user_id);
>> +	TST_EXP_EQ_LI(stat_buf.st_gid, group_id);
>
> So this would look like:
>
> 	uid_t usr_id = tc->user_id;
> 	gid_t grp_id = tc->group_id;
>
> 	SAFE_LSTAT(SFILE, &stat_buf);
>
> 	uid_t cmp_usr_id = usr_id == -1 ? stat_buf.st_uid : usr_id;
> 	uid_t cmp_grp_id = grp_id == -1 ? stat_buf.st_gid : grp_id;
>
> 	SAFE_LCHOWN(SFILE, user_id, group_id);
> 	SAFE_LSTAT(SFILE, &stat_buf);
> 	TST_EXP_EQ_LI(stat_buf.st_uid, cmp_user_id);
> 	TST_EXP_EQ_LI(stat_buf.st_gid, cmp_group_id);
>
> And this is exactly what the code was done before.

Thanks for the explanation!