Of Start Menu, Shortcuts and broken functions...

[Mike McCormack]

Hi Subhobroto,

Unfortunately, it's not just as simple as enumerating "C:\Windows\Start 
Menu", though that would be a good start.

To do things exactly the same way as Windows does them, we have to make 
a shell namespace that contains all the stuff on the start menu, then 
enumerate that.  Furthermore, since the namespace is dynamic, the menu 
really should be constructed on the fly, not just written to an .desktop 
file.

I had a bit of discussion with Robert van Herk about this (see the 
thread about ""Start menu" (continued)" on this list).  I mentioned to 
him that I thought the best way to solve the problem would be to write a 
gnome-vfs library and KDE plugin that query a wine process for the 
structure of the startmenu at runtime.

For starters we could just use the 'Start Menu' directory, but you miss 
out on things like Outlook Express and Internet Explorer's Icons, 
because there's no .lnk file for those... they are created by a shell 
namespace extension (I think :).

Anyway, it would be great if we figured out the remaining structure of 
.lnk files, and finished the IShellLink implementation properly, and no 
matter how things are done, we need that code to be complete.  The best 
way to do that, IMO, is to examine alot of .lnk files from windows 
systems :)

Mike


Subhobroto Sinha wrote:
> Hello all,
> 
> Recently there has been a revived interest in putting
> up a 'Windows' like 'Start Menu' onto the Window
> managers.
> That's good.Thanks.
> 
> But as I see it, this task is REALLY easy.
> Once we resolve the Windows shorcut files,figuring out
> how to implement the resolved menu entries for
> respective Desktop environments is dependent on the
> Desktop environment themselves, and people wanting to
> implement the 'Start Menu' on that environment.
> Windows maintains it's 'Start Menu' under
> '%ROOTDIR%\Documents and Settings\%USER%\Start Menu'
> (yeah I am talking >=NT,Win2k. For 9x, it will be
> probably 'C:\WINDOWS\Start Menu'), and this folder
> contains LOADS of shortcut (.lnk) files.
> So if we can just recurse through this folder and read
> out the .lnk files into compatible menu/desktop
> entries of the corresponding Desktop environment
> (KDE,GNOME...), we have a working, synchronized 'Start
> Menu'.
> 
> And that's JUST what McCormack's 'winemenubuilder'
> does, and reading out the code I can see it's THE
> thing we need.
> 
> Unfortunately, 'winemenubuilder' shipped from
> Wine-20030618 - the VERY version from which
> IPersistFile::Load() (the VERY function used to
> resolve windows shortcuts) got broken, so I could not
> see 'winemenubuilder' in practise!
> (Mike, if you are reading this, could you tell me on
> what Wine ver you originally developed it, and does
> 'winemenubuilder' work now ? Thanks)
> 
> You yourself may try out 'winemenubuilder', and if it
> works let me know. I will know that I was at fault all
> along,and that would be good news for me !
> 
> Now, there arises the problem. Microsoft really does
> not tell us what's the data structure of .lnk files,
> though if Alexandre (or somebody of his status..)
> requested Matt Pietrek for that information, we can
> probably get it.
> 
> Till then we are having to do with reverse engg., and
> let me tell you,that worked fine till Wine-20030618,
> i.e the Wine tarball release on the 18th June 2003.
>>From Wine-20030618 , the way Wine handled COM went a
> MAJOR overhaul, and it worked great in most cases and
> older code had to rewritten...
> .. and resolution of shortcuts just stopped working
> since then.
> So I have downgraded to using Wine 20030508 since it's
> the last version till which resolution of shortcuts
> works (though the code in 'shelllink.c' for this
> version is not nice to look at ;) ).
> 
> DETAILS:
> --------
> 
> You see, the resolving of shortcuts is handled through
> IPersistFile::Load() using COM.
> 
> The code for this instance of the interface can be
> found in 'dlls/shell32/shelllink.c'.
> IPersistFile::Load() calls IPersistFile_fnLoad from
> 'dlls/shell32/shelllink.c', which passes control to
> IPersistStream_Load() after a CreateStreamOnFile()
> call.
> Now the problem starts in IPersistStream_Load()
> at/after the following piece of code:
> 
> 'if( hdr.dwFlags & SCF_DESCRIPTION ) r =
> Stream_LoadString( pLoadStream, unicode,
> &This->sDescription );'...
> 
> Everything before this seems to work just fine!
> 
> [That's a pity because most of the time we just
> require the program location from the shortcut file,
> and that's ALWAYS dumped correctly into 'This->pPidl'
> You can verify this by adding the following code after
> 'r = Stream_LoadLocation( pLoadStream );' in
> 'shelllink.c'
> 
>         LPCITEMIDLIST pidltemp = This->pPidl;
>         do
>         {
>         char szSubho[MAX_PATH];
>         _dbg_ILSimpleGetText(pidltemp, szSubho,
> MAX_PATH);
>         TRACE ("name=\"%s\"\n",szSubho);
>         pidltemp = _dbg_ILGetNext(pidltemp);
>         }while (pidltemp->mkid.cb);
> 	You need to turn on the trace messages and you shall
> see the program path resolved allright!
> I had even tried to put a 'return S_OK;' after the
> Stream_LoadLocation() call,because ALL i required was
> the program path, but unfortunately that did NOT work
> :(
> ]
> 
> The call 'Stream_LoadString( pLoadStream, unicode,
> &This->sDescription );' works in some cases and fails
> in some. But you can be sure that all the following
> Stream_LoadString() calls starting from
> 'Stream_LoadString( pLoadStream, unicode,
> &This->sPathRel);' WILL fail!
> It did everytime on my SuSE 8.2,Wine-20030911.
> Thus, IPersistStream_fnLoad() will NEVER return S_OK !
> 
> The last time I debugged, I found that
> 'IStream_Read(pStm, &len, sizeof(len), &count);' under
> 'Stream_LoadString( IStream* pStm, BOOL unicode,
> LPWSTR *pstr )' was failing at/after the 'Description'
> string was read from the Windows shortcut file,
> apparently because the 'number of bytes read!=number
> of bytes to be read'( i.e, for those of you going
> through the 'shelllink.c' code, the 'count != len'
> condition was getting satisfied..)
> You may again verify this by turning on tracing and
> observing the messages for the above APIs from Wine
> while running my shortcut resolving code (found in the
> archives) OR McCormack's 'winemenubuilder'.
> 
> I hope to get a suitable response to this post. PLEASE
> correct me if I have gone wrong anywhere! Thanks :=)
> 
> Also, I will be VERY happy to recieve
> pseudocode/algorithm for the mentioned APIs specially
> Stream_LoadString() and IPersistStream_fnLoad() as I
> am having a hard time understanding a few lines in the
> code. And could someone send me the layout of .lnk
> files ?
> 
> Please keep up the good work.
> Regards
> 
> Subhobroto Sinha
> 
> __________________________________
> Do you Yahoo!?
> The New Yahoo! Shopping - with improved product search
> http://shopping.yahoo.com