RFR: 8218547: Simplify JLI_Open on Windows in native code (libjli) - was : RE: RFR : 8217093: Support extended-length paths in parse_manifest.c on windows

[Baesken, Matthias]

Hello, here is   the new webrev .

I  took over and adjusted  coding from       os::open  +  create_unc_path   functions   in os_windows.cpp   in hotspot  :

http://cr.openjdk.java.net/~mbaesken/webrevs/8218547.0/webrev/


Best regards, Matthias


> -----Original Message-----
> From: Baesken, Matthias
> Sent: Donnerstag, 21. März 2019 14:30
> To: Langer, Christoph <christoph.langer at sap.com>; Alan Bateman
> (Alan.Bateman at oracle.com) <Alan.Bateman at oracle.com>
> Cc: 'Chris Hegarty' <chris.hegarty at oracle.com>; 'core-libs-
> dev at openjdk.java.net' <core-libs-dev at openjdk.java.net>
> Subject: 8218547: Simplify JLI_Open on Windows in native code (libjli) - was :
> RE: RFR : 8217093: Support extended-length paths in parse_manifest.c on
> windows
> 
> Hi Alan + Christoph,   coming back to
> https://bugs.openjdk.java.net/browse/JDK-8218547  .
> 
> We wanted to check  for  the whole flow   (in JLI_Open  on Windows ) , e.g.
> checking whether only CreateFileW can be used instead of open.
> 
> I think  there is already  a similar solution available in the codebase .
> 
> See  the   os::open  +  create_unc_path   functions   in os_windows.cpp   in
> the hotspot coding .
> 
> There  "simple"  open  is used  for shorter  paths  ( <  MAX_PATH) ;  for larger
> paths  an elp / unc path is  constructed and _wopen is used on the   elp/unc
> path :
> 
> 
>   if (strlen(path) < MAX_PATH) {
>     ret = ::open(pathbuf, oflag | O_BINARY | O_NOINHERIT, mode);
>   } else {
>     errno_t err = ERROR_SUCCESS;
>     wchar_t* wpath = create_unc_path(pathbuf, err);
>      ....
>     ret = ::_wopen(wpath, oflag | O_BINARY | O_NOINHERIT, mode);
> 
> 
> I think we should  do it the same way in JLI_Open .  Is that fine with you?
> Unfortunately I think  we  cannot  easily  reuse  the HS coding, so the have to
> take it over to  jli .
> 
> Best regards, Matthias
> 
> 
> 
> > -----Original Message-----
> > From: Baesken, Matthias
> > Sent: Mittwoch, 6. Februar 2019 09:56
> > To: Langer, Christoph <christoph.langer at sap.com>
> > Cc: Chris Hegarty <chris.hegarty at oracle.com>; core-libs-
> > dev at openjdk.java.net; Alan Bateman (Alan.Bateman at oracle.com)
> > <Alan.Bateman at oracle.com>
> > Subject: RE: RFR : 8217093: Support extended-length paths in
> > parse_manifest.c on windows
> >
> > Hi  Christoph+Alan,  I opened
> >
> >
> > https://bugs.openjdk.java.net/browse/JDK-8218547
> >
> > JDK-8218547  :  use CreateFile without open on Windows in jdk native code
> >
> >
> > To check for  the usage of  CreateFile  (CreateFileW)   without open .
> >
> >
> > Best regards, Matthias
> >