[LTP] 答复: [PATCH] aio_error/3-1.c: Call write before aio_error

[Yang Xu]

Hi zou

We have a discussion about aio_return/aio_error in [1].
As Cyril said "For the open posix test you have to read the POSIX 
specification,
not the manuals that describe how the interface is implemented in Linux."

see https://pubs.opengroup.org/onlinepubs/9699919799/

you can search aio_error, it said "
The aio_error() function may fail if:
     [EINVAL]
         The aiocbp argument does not refer to an asynchronous operation 
whose return status has not yet been retrieved."
"
Now, I think we should keep old code. But we can add a new case 
（4-1.c)to test"the error status for an asynchronous I/O operation is
the errno value that would be set by thecorresponding read(), write(), ] 
fdatasync(), or fsync() operation".

@cyril, what do you think about this?

[1]https://patchwork.ozlabs.org/patch/1261239/

Best Regards
Yang Xu
> Hi All,
> 
> Does this patch need to be updated or modified?
> 
> Best Regards
> Zou Wei
> 
> -----邮件原件-----
> 发件人: Yang Xu [mailto:xuyang2018.jy@cn.fujitsu.com]
> 发送时间: 2020年3月20日 16:15
> 收件人: Zouwei (Samuel) <zou_wei@huawei.com>
> 抄送: ltp@lists.linux.it
> 主题: Re: [LTP] [PATCH] aio_error/3-1.c: Call write before aio_error
> 
> Hi Zou
> 
>> In the case, if there is no write/read operation before aio_error,
>> aio_error will judge that the current asynchronous I/O has been
>> successfully completed, then return 0, case failed.
>>
>> After the write/read operation is added, because aiocb.aio_reqprio is
>> -1, the write/read operation will return -1, so aio_error will also
>> return EINVAL because it detects that the asynchronous I/O has not completed successfully.
> I have seen glibc code about aio_write and aio_err function, you are right. Thanks for the fix.
> 
> Looks good to me.
> Reviewed-by: Yang Xu <xuyang2018.jy@cn.fujitsu.com>
> 
> Best Regards
> Yang Xu
>>
>> ps:
>> http://man7.org/linux/man-pages/man3/aio_error.3.html
>> RETURN VALUE
>>          This function returns one of the following:
>>          *  EINPROGRESS, if the request has not been completed yet.
>>          *  ECANCELED, if the request was canceled.
>>          *  0, if the request completed successfully.
>>          *  A positive error number, if the asynchronous I/O operation failed.
>>             This is the same value that would have been stored in the errno
>>             variable in the case of a synchronous read(2), write(2), fsync(2),
>>             or fdatasync(2) call.
>> ERRORS
>>          EINVAL aiocbp does not point at a control block for an asynchronous
>>                 I/O request of which the return status (see aio_return(3)) has
>>                 not been retrieved yet.
>>
>> Signed-off-by: Zou Wei <zou_wei@huawei.com>
>> ---
>>    .../open_posix_testsuite/conformance/interfaces/aio_error/3-1.c      | 5 +++++
>>    1 file changed, 5 insertions(+)
>>
>> diff --git
>> a/testcases/open_posix_testsuite/conformance/interfaces/aio_error/3-1.
>> c
>> b/testcases/open_posix_testsuite/conformance/interfaces/aio_error/3-1.
>> c
>> index 9ccda05..2b2c65b 100644
>> ---
>> a/testcases/open_posix_testsuite/conformance/interfaces/aio_error/3-1.
>> c
>> +++ b/testcases/open_posix_testsuite/conformance/interfaces/aio_error/
>> +++ 3-1.c
>> @@ -64,6 +64,11 @@ int main(void)
>>    	aiocb.aio_reqprio = -1;
>>    	aiocb.aio_nbytes = BUF_SIZE;
>>
>> +	if (aio_write(&aiocb) != -1) {
>> +                printf(TNAME " Error at aio_write(): %s\n", strerror(errno));
>> +                return PTS_FAIL;
>> +        }
>> +
>>    	ret = aio_error(&aiocb);
>>
>>    	if (ret != EINVAL) {
>> --
>> 2.6.2
>>
>>
> 
> 
> 
>