RFR: 8232846: ProcessHandle.Info command with non-English shows question marks

[Roger Riggs]

Hi,

Please don't throw an exception.
It would abort being able to provide any information.
And who would expect or handle such an exception?

Degrading the info or omitting it provides better service overall.
There is no point to throwing an exception.

Regards, Roger


On 3/26/20 7:55 PM, Yasumasa Suenaga wrote:
> On 2020/03/27 0:35, Roger Riggs wrote:
>> Hi,
>>
>> Reading further down the reference to the section:
>> "Enable Long Paths in Windows 10, Version 1607, and Later"
>> might suggest the code be more resilient to long paths.
>>
>> The stack allocated buffer (1024) is fine, but I'd suggest adding 
>> code to retry in the case
>> of INSUFFICIENT BUFFER with a malloc'd buffer to make it more robust 
>> since the enabling
>> of long paths is environment and application specific.
>
> In addition, it's better to throw an exception if the call failed due 
> to other error code.
>
> Thanks,
>
> Yasumasa
>
>
>> Thanks, Roger
>>
>>
>>
>> On 3/26/20 10:40 AM, Toshio 5 Nakamura wrote:
>>> Hi Thomas, Suenaga-san, Roger,
>>>
>>> Thank you for reviewing and comments.
>>>
>>> I checked behaviors by a small program and debugger.
>>> If QueryFullProcessImageNameW failed by not enough buffer,
>>> the API didn't change the buffer.
>>> It just set ERROR_INSUFFICIENT_BUFFER(0x7a) to LastError.
>>>
>>> The buffer size becomes 1024 characters (2048 bytes) by this patch.
>>> Should it use bigger size with malloc? 32,767 characters can be 
>>> limit [2].
>>> I feel 1024 is reasonable value for command's location.
>>>
>>> [2]
>>> https://urldefense.com/v3/__https://docs.microsoft.com/en-us/windows/win32/fileio/naming-a-file*maximum-path-length-limitation__;Iw!!GqivPVa7Brio!PgzCcUQOjCNpcVeetU_drS4DFFVLaj0ceJBvipX7iDc_RlPtcEkdH8AzelGtzqXS$ 
>>>
>>> Best regards,
>>> Toshio Nakamura
>>>
>>>> Hi,
>>>>
>>>> If the call fails, the command field in the info will not be set (and
>>>> therefore null).
>>>>
>>>> I agree that a length of 512 (characters) is probably too small.
>>>>
>>>> Roger
>>>>
>>>>
>>>> On 3/26/20 6:37 AM, Yasumasa Suenaga wrote:
>>>>> Hi Nakamura-san,
>>>>>
>>>>> Your change almost looks good, but I have one question.
>>>>> Length of exeName (1024) is enough?
>>>>>
>>>>> According to Microsoft Doc [1], exeName might not be null-terminated
>>>>> if it failed.
>>>>> I concern buffer overrun might occur when QueryFullProcessImageNameW
>>>>> failed.
>>>>>
>>>>>
>>>>> Thanks,
>>>>>
>>>>> Yasumasa
>>>>>
>>>>>
>>>>> [1]
>>> https://urldefense.proofpoint.com/v2/url?u=https-3A__docs.microsoft.com_en-2Dus_windows_win32_api_winbase_nf-2Dwinbase-2Dqueryfullprocessimagenamew&d=DwICaQ&c=jf_iaSHvJObTbx-siA1ZOg&r=EVbFABcgo-X99_TGI2-qsMtyulHUruf8lAzMlVpVRqw&m=noFyLWDG1dMjO5TlaqM_zvW_f-8fvveS2EoZylT5DMQ&s=oc_KTGmJUjsfnLf3tjWr9DO1dwWp1TqIZgd2EiHVW14&e= 
>>>
>>>
>>>>>
>>>>> On 2020/03/26 17:58, Toshio 5 Nakamura wrote:
>>>>>> Hi All,
>>>>>>
>>>>>> Could you review this change? Additionally, I'd like to ask a 
>>>>>> sponsor
>>>>>> for
>>>>>> it, since I'm not a committer.
>>>>>>
>>>>>> Bug:
>>> https://urldefense.proofpoint.com/v2/url?u=https-3A__bugs.openjdk.java.net_browse_JDK-2D8232846&d=DwICaQ&c=jf_iaSHvJObTbx-siA1ZOg&r=EVbFABcgo-X99_TGI2-qsMtyulHUruf8lAzMlVpVRqw&m=noFyLWDG1dMjO5TlaqM_zvW_f-8fvveS2EoZylT5DMQ&s=pn_uS0DojBk6-R6R5QwtYFJvJpaabhia-eiOtIrJO9Q&e= 
>>>
>>>
>>>>>> Webrev:
>>> https://urldefense.proofpoint.com/v2/url?u=http-3A__cr.openjdk.java.net_-7Etnakamura_8232846_webrev.00&d=DwICaQ&c=jf_iaSHvJObTbx-siA1ZOg&r=EVbFABcgo-X99_TGI2-qsMtyulHUruf8lAzMlVpVRqw&m=noFyLWDG1dMjO5TlaqM_zvW_f-8fvveS2EoZylT5DMQ&s=NylYK0Q3nFFZRVIaeUna6iaClaJm1CWJ2Zkwy-ysvv4&e= 
>>>
>>>
>>>>>> Under Windows environments, ProcessHandle.Info.command shows 
>>>>>> question
>>>>>> marks
>>>>>> if the command has non-English characters. I'd like to change the
>>>>>> underlying API to Unicode version.
>>>>>> Tier1 tests passed.
>>>>>>
>>>>>> Best regards,
>>>>>> Toshio Nakamura
>>>>>>
>>