Hi Malcolm,
On 21.11.2016 23:34, Malcolm Clarke wrote:
Dear Klaus
Thank you for your response.
You have not understood the issue that is being reported. I have made
an effort to examine code to understand, but the software is complex,
with a multiplicity of "methods" to acquire the directory for the
configuration file (eg search for "HOMEDRIVE").
I did understand your issue, but I have absolutely no explanation why it
could possibly happen with a properly configured roaming profile setup.
VirtualBox doesn't use any environment variables for figuring out the
user's profile directory, it directly asks the Windows API. I don't
think that makes the situation more complex, in my opinion it makes it a
lot simpler. All the fallbacks which you investigated are simply not
relevant (unless you found a way to make the Windows API fail in
extremely weird patterns).
I repeat the behaviour.
Our students are working on machines using roaming profile with
USERPROFILE=c:\user\xxxxxx, HOMEDRIVE=h:, HOMEPATH=\
When the student first uses VirtualBox and opens the manager, it has a
totally empty configuration as expected. The student then creates some
networks and virtual machines. These machines work correctly when started.
The student exits the manager.
The student restarts the manager but is confronted with an empty
configuration, all previous settings are lost.
That's the riddle. I don't have the faintest idea why the settings are
suddenly gone. It's somewhat difficult to investigate, too, as tools
like procmon don't feel that much at home with situations like user
logout or roaming profiles. But it is still worth a try, having it
monitor the activities on logout or when VirtualBox is started again.
It is very frustrating having to create NAT networks and virtual
machines every time the manager is restarted.
No doubt.
If a single method was used to return the directory, then I would
expect the behaviour to be different, and the configuration retained
and appear each time the manager is opened, ie the behaviour the same
as when installed on a stand alone machine. This is not the case, and
so there is an issue.
There is only a single method for determining the location of the
.VirtualBox directory, and it does not depend on environment variables
which are unreliable.
I would expect this to be an issue for any classroom situation where
roaming profiles are used and separate home drives are defined - a
common configuration.
No, I don't believe that what you're seeing is a generic roaming profile
issue. Otherwise we'd get complains from a lot more people out there
operating some non-trivial Windows setups.
I also hope you appreciate Universities introducing and using Virtual
Box in teaching, but we require support.
We certainly do, otherwise we wouldn't have created the "free ride"
option for educational purposes.
Regards,
Klaus
Regards
Malcolm
On 21/11/2016 11:02, Klaus Espenlaub wrote:
Malcolm,
there was a lengthy reply to the mailing list 10 days ago sent by me,
explaining what's going on.
Your assumption is wrong. VirtualBox on all Windows versions worth
talking about will NOT fall through, it'll use the profile directory
returned by SHGetFolderPath.
Klaus
On 20.11.2016 19:55, Malcolm Clarke wrote:
Dear Max
Still no response.
Looking at path-win.cpp, the following code is unclear
RTDECL(int) RTPathUserHome(char *pszPath, size_t cchPath)
{
/*
* Validate input
*/
AssertPtrReturn(pszPath, VERR_INVALID_POINTER);
AssertReturn(cchPath, VERR_INVALID_PARAMETER);
RTUTF16 wszPath[RTPATH_MAX];
bool fValidFolderPath = false;
/*
* Try with Windows XP+ functionality first.
*/
RTLDRMOD hShell32;
int rc = RTLdrLoadSystem("Shell32.dll", true /*fNoUnload*/,
&hShell32);
if (RT_SUCCESS(rc))
{
PFNSHGETFOLDERPATHW pfnSHGetFolderPathW;
rc = RTLdrGetSymbol(hShell32, "SHGetFolderPathW",
(void**)&pfnSHGetFolderPathW);
if (RT_SUCCESS(rc))
{
HRESULT hrc = pfnSHGetFolderPathW(0, CSIDL_PROFILE,
NULL, SHGFP_TYPE_CURRENT, wszPath);
fValidFolderPath = (hrc == S_OK);
}
RTLdrClose(hShell32);
}
DWORD dwAttr;
if ( !fValidFolderPath
|| (dwAttr = GetFileAttributesW(&wszPath[0])) ==
INVALID_FILE_ATTRIBUTES
|| !(dwAttr & FILE_ATTRIBUTE_DIRECTORY))
{
/*
* Fall back to Windows specific environment variables. HOME
is not used.
*/
if ( !GetEnvironmentVariableW(L"USERPROFILE",
&wszPath[0], RTPATH_MAX)
|| (dwAttr = GetFileAttributesW(&wszPath[0])) ==
INVALID_FILE_ATTRIBUTES
|| !(dwAttr & FILE_ATTRIBUTE_DIRECTORY))
{
/* %HOMEDRIVE%%HOMEPATH% */
if (!GetEnvironmentVariableW(L"HOMEDRIVE", &wszPath[0],
RTPATH_MAX))
return VERR_PATH_NOT_FOUND;
size_t const cwc = RTUtf16Len(&wszPath[0]);
if ( !GetEnvironmentVariableW(L"HOMEPATH",
&wszPath[cwc], RTPATH_MAX - (DWORD)cwc)
|| (dwAttr = GetFileAttributesW(&wszPath[0])) ==
INVALID_FILE_ATTRIBUTES
|| !(dwAttr & FILE_ATTRIBUTE_DIRECTORY))
return VERR_PATH_NOT_FOUND;
}
}
Assuming this falls through to get the environment variable, then
USERPROFILE is used over %HOMEDRIVE%%HOMEPATH%, however in most
other places %HOMEDRIVE%%HOMEPATH% alone is used. This appears to
result in inconsistent behaviour if USERPROFILE is not equal to
%HOMEDRIVE%%HOMEPATH%.
This needs to be remedied for people using roaming profiles when
these environmental variables can be set differently.
1. %HOMEDRIVE%%HOMEPATH% is used for location of configuration files
(create and check location for existence)
2. USERPROFILE may be used for temporary files
Regards
Malcolm
On 09/11/2016 14:36, Maxime Dor wrote:
Hi Malcolm,
While I have extensive knowledge of VBox, I'm not a dev so I can't
really answer that question, only the devs can.
They should answer anytime soon now! If they don't be tomorrow,
just let me know and I'll drop them a note.
Max
--
*Malcolm Clarke *BSc (Hons), PhD
Reader in Telemedicine and Data Communication Systems
T+44 (0) 1895 265053
*Brunel University London*
College of Engineering, Design and Physical Sciences
Department of Computer Science
HNZW010, Heinz Wolff Building, Kingston Lane, Uxbridge, Middlesex,
UB8 3PH
*www.brunel.ac.uk <http://www.brunel.ac.uk/>*
Connect with the university on*Linkedin, Twitter, Facebook*
--
*Malcolm Clarke *BSc (Hons), PhD
Reader in Telemedicine and Data Communication Systems
T+44 (0) 1895 265053
*Brunel University London*
College of Engineering, Design and Physical Sciences
Department of Computer Science
HNZW010, Heinz Wolff Building, Kingston Lane, Uxbridge, Middlesex, UB8 3PH
*www.brunel.ac.uk <http://www.brunel.ac.uk/>*
Connect with the university on*Linkedin, Twitter, Facebook*
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