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

Toshio 5 Nakamura TOSHIONA at jp.ibm.com
Fri Mar 27 10:46:09 UTC 2020


Thank you for review, Suenaga-san, Thomas.

(My mail in html format was blocked by the list. Sorry for inconvenience.)

The latest webrev is 02:
http://cr.openjdk.java.net/~tnakamura/8232846/webrev.02/

Thanks,
Toshio

> From: Yasumasa Suenaga <suenaga at oss.nttdata.com>
>
> Ok, your change looks good.
>
>
> Thanks,
>
> Yasumasa
>
> On 2020/03/27 18:10, Toshio 5 Nakamura wrote:
> > Hi Suenaga-san,
> > Thank you for the comment. I updated the limit to 32768.
> > webrev.02:
https://urldefense.proofpoint.com/v2/url?u=http-3A__cr.openjdk.java.net_-7Etnakamura_8232846_webrev.02&d=DwIDaQ&c=jf_iaSHvJObTbx-siA1ZOg&r=EVbFABcgo-X99_TGI2-qsMtyulHUruf8lAzMlVpVRqw&m=wzpmzDaZdDfLKNqZprr1X6d_EdWvLpBWS6fMzVNeu3w&s=PIzjJwY4DhVqnxGp-4WusnNS4MlBy9PEGoCiCE9Hnaw&e=

> > Well, I believe the new logic works as same as the current one.
> > I added NULL initialization to commandObj, and the value will be
> changed only if QueryFullProcessImageNameW() was success.
> > Then, CHECK_NULL(commandObj) works as "return" if commandObj is NULL.
> > src/java.base/share/native/libjava/jni_util.h
> >  > #define CHECK_NULL(x)                           \
> >  >     do {                                        \
> >  >         if ((x) == NULL) {                      \
> >  >             return;                             \
> >  >         }                                       \
> >  >     } while (0)                                 \
> > I hope this solves your concern.
> > Best regards,
> > Toshio Nakamura
> >
> >     ----- Original message -----
> >     Nakamura-san,
> >
> >     I think location of CHECK_NULL and SetObjectField() are incorrect.
> >     Currently they are called when QueryFullProcessImageName() succeed
only.
> >
> >     In addition, you need to allocate 32768 chars (32767 + 1 ('\0'))
via malloc.
> >     I understand "32767" is max length, not includes null-terminator.
> >
> >
> >     Thanks,
> >
> >     Yasumasa
> >
> >
> >     On 2020/03/27 14:06, Toshio 5 Nakamura wrote:
> >      >
> >      > Hi Roger, Suenaga-san,
> >      >
> >      > Thank you for your comments and discussion for the issue.
> >      > I've updated webrev. Could you review it again?
> >      > tier1 tests passed.
> >      >
> >      > webrev.01:
https://urldefense.proofpoint.com/v2/url?u=http-3A__cr.openjdk.java.net_-7Etnakamura_8232846_webrev.01&d=DwIDaQ&c=jf_iaSHvJObTbx-siA1ZOg&r=EVbFABcgo-X99_TGI2-qsMtyulHUruf8lAzMlVpVRqw&m=wzpmzDaZdDfLKNqZprr1X6d_EdWvLpBWS6fMzVNeu3w&s=sSZ6mylujPpWlHliOmnz9ukEJoaJrOnLJWuTptntVj8&e=

> >      >
> >      > Best regards,
> >      > Toshio Nakamura
> >      >
> >      > Yasumasa Suenaga <suenaga at oss.nttdata.com> wrote on 2020/
> 03/27 09:10:15:
> >      >
> >      >> On 2020/03/27 9:01, Roger Riggs wrote:
> >      >>> 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.
> >      >>
> >      >> hProcess in QueryFullProcessImageNameW needs
> >      >> PROCESS_QUERY_INFORMATION or PROCESS_QUERY_LIMITED_INFORMATION
> >      >> access right, so I thought it is reasonable to throw runtime
> >      >> exception if the call failed.
> >      >>
> >      >> Anyway, I agree with you if throwing exception is not
comfortable in
> >      >> this case for Java API.
> >      >>
> >      >>
> >      >> Thanks,
> >      >>
> >      >> Yasumasa
> >      >>
> >      >>
> >      >>> 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 probablytoo
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=DwIDaQ&c=jf_iaSHvJObTbx-siA1ZOg&r=EVbFABcgo-X99_TGI2-qsMtyulHUruf8lAzMlVpVRqw&m=wzpmzDaZdDfLKNqZprr1X6d_EdWvLpBWS6fMzVNeu3w&s=V6oP8SJvlxIc2iOxIOAcY6_mznTaxta2tyCV2iVzD3I&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=DwIDaQ&c=jf_iaSHvJObTbx-siA1ZOg&r=EVbFABcgo-X99_TGI2-qsMtyulHUruf8lAzMlVpVRqw&m=wzpmzDaZdDfLKNqZprr1X6d_EdWvLpBWS6fMzVNeu3w&s=8iQnOHT0GkoAZsYE39mDmx8036dUvvDbcj4tjCaPyps&e=

> >      >
> >      >>>>>>
> >      >>>>>>>>> Webrev:
> >      >>>>>>
> >      >
https://urldefense.proofpoint.com/v2/url?u=http-3A__cr.openjdk.java.net_-7Etnakamura_8232846_webrev.00&d=DwIDaQ&c=jf_iaSHvJObTbx-siA1ZOg&r=EVbFABcgo-X99_TGI2-qsMtyulHUruf8lAzMlVpVRqw&m=wzpmzDaZdDfLKNqZprr1X6d_EdWvLpBWS6fMzVNeu3w&s=0avs_hvCJdUYCP8WPu8Ttlo4sLwbwuFs2wWV0Szc9gg&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
> >      >>>>>>>>>


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