Projects/KDE on Windows/Windows CE

    From KDE TechBase
    Revision as of 14:18, 11 December 2009 by Aheinecke (talk | contribs) (Windows Mobile/Windows CE Information)

    Introduction

    This page describes a work in progress, there are no KDE Applications running on Windows Mobile (that I know of). It is only intended to give a starting point to developers for cross compilation and Windows CE related issues. Since Qt is already ported for Windows CE it should be possible to get some KDE applications running on that Platform.

    Windows CE / Windows Mobile

    Although Windows CE (officially called Windows Embedded CE) is part of the Windows Embedded family there is a large difference between Windows Embedded CE and other Windows Embedded products. Most importantly Windows CE is not Windows. It has a different Kernel then any other Windows Operating System. And while other embedded products like Windows Embedded Standard or Windows Embedded Enterprise (which are sized down versions of Windows XP), will run Windows applications without problems, Windows CE applications require porting even from Windows.
    Windows Mobile then is based on Windows CE (CE has no official meaning) and it's current Versions Windows Mobile 6.1 (and 6.5) are based on Windows CE 5.0 so we will be talking about developing for Windows CE 5.0 when we are talking about developing for Windows Mobile >= 6.1 It is confusing but Windows Mobile 6 is not based on Windows CE 6 so it still has the limitations of Windows CE 5. For example the process address space is still limited to 32 MB and the maximum Number of processes can not exceed 32.


    Building Qt for Windows CE with MSVC

    Setting up Visual Studio

    First thing you need is Visual Studio professional or standard edition (preferably with service pack 1). Be aware that the express editions are explicitly not supported for Windows CE development.
    (You could use Microsoft Embedded VC which is cost-free, but depreciated and not supported by Qt)
    Next thing you need is a Microsoft Windows Mobile Platform SDK corresponding to your target platform. Just search the Microsoft download pages or get the Windows Mobile 6 SDK from here (You should take a loot at the System Requirements)
    If everything is set up correctly you should now be able to create a “Visual C++ smart device" project in Visual Studio.
    Note on Version-Naming: Standard means without touchscreen, Professional means with Touchscreen and Classic means Windows Mobile without mobile phone capabilities

    More about Visual Studio and Windows Mobile development: http://msdn.microsoft.com/en-us/library/dd721907.aspx

    Building Qt

    Download the Qt libraries for Windows CE from http://qt.nokia.com/downloads/win-ce-cpp and extract it, you may want to make sure that your path contains no blanks to avoid some problems.
    Now you should add your <qt-directory>\bin to your Windows PATH environment variable (which can be done from “Control Panel → System → Advanced →Environment variables” )

    Next get up your Visual Studio Command Prompt which should be accessible from the Windows Start Menu. Change the working directory to qt-directory and start the configuration. There should be a configuration.exe in your qt-directory with the usual options, (configure.exe -help for more info) for cross compiling you need to give at least the -platform parameter with your host system and -xplatform with your cross-compile target. Supported platforms are listed in the README file. e.g.:

    configure.exe -platform win32-msvc2008 -xplatform wincewm60standard-msvc2008

    Now that your configuration is set you can start the cross compilation. To switch from your “normal” build environment to the wince target Qt has a nice script included in the /bin directory (which should be in your PATH) just try calling setcepaths and provide your target configuration.
    setcepaths wincewm60standard-msvc2008
    With nmake (Visual Studio version of make) you can now build Qt for your target system.


    Building Qt for Windows CE with CeGCC

    Getting CeGCC

    CeGCC (http://cegcc.sourceforge.net/) is a free cross-development environment for ARM-based systems running Windows CE. It is not officially supported by Qt and work with it is highly experimental, but given some work it could be possible to use it to build KDE-applications for Windows Mobile.

    You can get CeGCC here: http://sourceforge.net/projects/cegcc/files/cegcc/0.59.1/mingw32ce-0.59.1.tar.bz2/download
    Or to build the latest Version yourself see: http://cegcc.sourceforge.net/docs/build-toolchain.html


    Building Qt

    Maurice Kalinowski at Nokia did some work on this and provided a working Qt-Version with make specs for mingw32ce that make it possible to build most of the Qt parts. The original mailing-list thread discussing this can be found here: http://lists.trolltech.com/pipermail/qt-wince-interest/2009-November/000764.html

    Link to the gitorious repository: http://gitorious.org/+qt-developers/qt/ce-gcc

    After downloading you should take a look at the cegcc_configure script, maybe change the installation prefix there and then execute it. If your configuration fails make sure that your environment is not yet set for cross-compiling.

    When configuration is complete you can build the host-tools, just go into your checkout and execute:
    {

           QTCEDIR=$(pwd)
           folders="bootstrap moc uic rcc"
           for f in $folders; do
               cd $QTCEDIR/src/tools/$f && $QTCEDIR/bin/qmake -spec $QTCEDIR/mkspecs/linux-g++ && make && cd $QTCEDIR || return
           done
    

    }

    If the tools were built you now need to set up your environment for cross-compiling.

            export MINGWPATH=/opt/mingw32ce
            export INCLUDE=$MINGWPATH/arm-mingw32ce/include:$MINGWPATH/include:$INCLUDE
            export LIB=$MINGWPATH/arm-mingw32ce/lib:$MINGWPATH/lib:$LIB
            export PATH=$MINGWPATH/bin:$MINGWPATH/arm-mingw32ce/bin:$MINGWPATH/libexec/gcc/arm-mingw32ce/4.4.0:$PATH
    

    Of course you have to change MINGWPATH according to your installation.

    Now all that is left to do is to build Qt for the target system, to do that (again from your checkout directory) execute:
    {

           QTCEDIR=$(pwd)
           folders="winmain corelib gui"
           for f in $folders; do
               cd $QTCEDIR/src/$f && $QTCEDIR/bin/qmake && make && make install && cd $QTCEDIR || return
           done
    

    } This will build the qtcore and qtgui, you can try building more parts, of course.


    Notes:

    - in case of pch errors delete .pch/release-static-emb-windowsce/qt_gui_pch.h.gch directory

    - when you are compiling your application outside of the Qt tree, you might get into trouble related to mkspecs and include dirs.

    - for deployment you need to copy these files also to the same directory on the device:

       libgcc_s_sjlj-1.dll
       libstdc++-6.dll
     which are located inside the arm-mingw32ce directory
    

    - Currently Windows Mobile > 6.0 does not load the libgcc_s_sjlj-1.dll libstdc++-6.dll properly, but a fix is in the works, see:

    http://www.mail-archive.com/[email protected]/msg02699.html



    Packaging:

    Deploying Qt Windows Mobile Applications using LCAB

    LCAB is a free software utility, that has the ability to create Microsoft CAB archives. You can get it on ( http://packages.debian.org/lenny/lcab )or as a Debian package.

    Now that you can create cabinet files, the question is how to get Windows Mobile to recognize them as install packages. Thanks to Shaun Jackman this, also is no Problem. He wrote a Perl script to add the needed manifest and setup configuration file. You can find it under ( http://files.intevation.de/incoming/aheinecke/cab_files/pocketpc-cab.pl ) There is also a pocketpc-cab Debian packet out there, which does not support registry entries or the creation of shortcuts.

    This script needs a configuration file, like Cabwiz but it is much more simple then the Cabwiz variant. Simply write down for every file you want to package:

    Filename Target-Directory [Shortcut Name] [Shortcut Folder] for example the Qt widget collidingmice: collidingmice.exe %CE1%/Colliding_Mice "Colliding Mice" %CE11% msvcr90.dll %CE2% QtCore4.dll %CE2% QtGui4.dll %CE2%

    This installs collidingmice.exe to Program Files/Colliding_Mice , places a shortcut in the Start Menu folder and copies the libraries into the Windows directory.

    CE Variables

    Here are some predefined Windows CE variables which can be used to identify a path on a Windows CE device.

          %CE1%	\Program Files
          %CE2%	\Windows
          %CE4%	\Windows\StartUp
          %CE5%	\My Documents
          %CE6%	\Program Files\Accessories
          %CE7%	\Program Files\Communication
          %CE8%	\Program Files\Games
          %CE11%	\Windows\Start Menu\Programs
          %CE12%	\Windows\Start Menu\Programs\Accessories
          %CE13%	\Windows\Start Menu\Programs\Communications
          %CE14%	\Windows\Start Menu\Programs\Games
          %CE15%	\Windows\Fonts
          %CE17%	\Windows\Start Menu
    

    Deploying Qt Windows Mobile Applications using Cabwiz

    Maybe in some situations Cabwiz has its relevance, (e.g. you only want to build from windows) but even then i would suggest to directly edit the setup.xml that is included in the Cabinet file. This should be easier then working with Cabwiz to generate the setup.xml

    Microsoft Cabwiz is part of Microsofts Windows Mobile SDKs

    I will try to demonstrate the usage of Cabwiz and the inf file format by creating a small configuration example to install the Qt example Tetrix, which comes as part of the Qt package, on a Windows Mobile Device.

    If you built Qt using msvc you need to deploy 4 files to the Windows CE device:

           Tetrix.exe      ; the program <yourqtdir>\examples\widgets\tetrix\release       
           QtCore4.dll   ; shared Qt library <yourqtdir>\lib
           QtGui4.dll     ;  shared Qt library <yourqtdir>\lib
           msvcr90.dll   ; choose the MS Visual C runtime according to your developing environment
    

    The goal is to get the installer to install the program to \Program Files\Tetrix and copy the shared libraries into the Windows folder, so other applications can find them as well, with also inserting a link in Start Menu\Games to our Tetrix.exe.

    To use Cabwiz for that, you need to provide it with an [information file Information file documentation: http://msdn.microsoft.com/en-us/library/aa924371.aspx] which details the configuration of the deployment package and which files there are to Include.

    An inf file consist of different Sections you have to provide, the first one of those is CEStrings which defines the Application Name and the InstallDir where the files are to be placed.

          [CEStrings]
          AppName="Tetrix"
          InstallDir=%CE1%\%AppName%
    

    With the % tags we tell the interpreter that AppName and CE1 are variables. CE1 is defined by Windows Mobile and stands for the Program Files directory.

    Next the Version section:

          [Version]
          Signature="$Windows NT$"
          CESignature="$Windows CE$"
          Provider=”Cabwiz”
    

    Provider is meant for the creator of the application and is used to help identify the program if you leave it at Cabwiz WinCE will refer to your program as “Cabwiz Tetrix”.

    To create a shortcut that is later inserted into the start menu:

          [Shortcuts]
          %AppName%,0,”tetrix.exe”
    

    AppName is the name for our shortcut, 0 means its a file (1 would mean its a folder), and “tetrix.exe” is the executable. The path used for the shortcut is taken from InstallDir by default

    Now to the files. First you have to tell Cabwiz where it can find the files you want to include in the cab file. So for each directory you have to create a name in the SourceDiskNames Section. To keep it simple all the files in this example are in c:\tetrix

          [SourceDisksNames]
          1=,"arm files",,c:\tetrix
    

    To declare the SourceFiles, the files to include in the cabinet file:

          [SourceDisksFiles]
          tetrix.exe=1
          QtCore4.dll=1
          QtGui4.dll=1
          msvcr90.dll=1
    

    Those files all are in c:\tetrix defined in section SourceDiskNames as 1.

    Since the goal is to put the shared libraries in the Windows directory and the Tetrix.exe under Program files Cabwiz has to be made aware that they are different. For this reason you can create “copyfile sections” that you can name yourself. For example the two sections:

          [ProgramFiles]
          tetrix.exe
    
          [SharedLibs]
          QtCore4.dll,,,0xA0000000
          QtGui4.dll,,,0xA0000000
          msvcr90.dll,,,0xA0000000
    

    Only the file name is mandatory here, the arguments are optional. With the flag 0xA0000000 you tell the installer that those files are shared, and should only be replaced if they are newer then files that may be already on the device. For more on that see: http://msdn.microsoft.com/en-us/library/aa924416.aspx

    Two sections are left which are needed to create a .cab file, DefaultInstall and DestinationDirs:

          [DefaultInstall]
          CeShortcuts=Shortcuts
          CopyFiles=ProgramFiles,SharedLibs
    

    DefaultInstall just declares how the shortcuts and file lists are named.

    Finally, to declare where everything should be copied to:

          [DestinationDirs]
          Shortcuts=,%CE14%
          ProgramFiles=,%InstallDir%
          SharedLibs=,%CE2%  
    

    Notice again the CE variables, for more information see the Mobile SDK help files.

    Thats it, now all you have to do is to start Cabwiz from the command line and provide the .inf file. for a more detailed reference see: http://www.osronline.com/ddkx/install/create-inf_4l47.htm or just use lcab.

    Tetrix.inf:

          [CEStrings]
          AppName="Tetrix"
          InstallDir=%CE1%\%AppName%
          [Version]
          Signature="$Windows NT$"
          CESignature="$Windows CE$"
          Provider=”Company”
    
          [Shortcuts]
          %AppName%,0,”tetrix.exe”
    
          [SourceDisksNames]
          1=,"arm files",,c:\tetrix
    
          [SourceDisksFiles]
          tetrix.exe=1
          QtCore4.dll=1
          QtGui4.dll=1
          msvcr90.dll=1
    
          [ProgramFiles]
          tetrix.exe
    
          [SharedLibs]
          QtCore4.dll,,,0xA0000000
          QtGui4.dll,,,0xA0000000
          msvcr90.dll,,,0xA0000000
    
          [DefaultInstall]
          CeShortcuts=Shortcuts
          CopyFiles=ProgramFiles,SharedLibs
    
          [DestinationDirs]
          Shortcuts=,%CE14%
          ProgramFiles=,%InstallDir%
          SharedLibs=,%CE2%
    


    Building KDE for Windows CE using MSVC

    Problems with MSVC

    Who needs standard C when he can have "Visual" C seems to be the reasoning. If you try to port native code from Linux to Windows CE or even from Windows to Windows CE you will soon run into walls because Microsoft does not provide you with a C-Library that is in any way complete or following standards. This is ugly when some parts are missing like errno, fcntl, types, stat, ... but gets even more ugly when there are the headers, but not the library functions like Microsoft's complete string.h is the line:

          #include <stdlib.h>
    

    nothing more. Maybe the best way to go here would be to delete those "dummy files" or reroute them to a compatibility library?


    Compatibility Libraries

    CELIB

    With all the Problems there are with Windows CE C-Libraries it was actually much worse in older Windows CE versions. Rainer Keuchel did a lot of porting back in 2003 ( http://www.rainer-keuchel.de/software.html ) and wrote celib which provides many of the functions Windows CE is lacking. Sadly, this project died and has not been maintained to fit current Windows Versions. But maybe it can help with some ideas for workarounds or to cannibalize some parts.

    wcelibcex

    Wcelibcex supplements the Windows CE C-library with functions and workarounds for porting applications from Unix and Windows to Windows CE. Originally, the WCELIBCEX development was founded by Taxus SI Ltd. and in 2005 released as an Open Source Software project. The WCELIBCEX project is currently maintained by Mateusz Łoskot. ( http://wcelibcex.sourceforge.net/ )

    At a first glance this project is still active, at least the SVN Version is updated now and then. I've had some success using it but it also is not as complete as one would hope. There are some interesting ideas implemented, like managing the environment through the Windows registry. There would is still a lot to include if we wanted to build without modifying the public libraries but it would give a good starting point.


    Dependencies

    Following the Getting Started/Build/KDE4/Windows/Building DBus guide we need at least the following libraries.

       * aspell  
       * boost-headers
       * bzip2
       * cyrus-sasl
       * expat
       * giflib
       * gpgme
       * iconv
       * jasper
       * jpeg
       * kdewin32
       * libintl
       * libpng ( ported V 1.2.3 )
       * libxml2
       * libxslt
       * openldap
       * openslp
       * openssl
       * pcre
       * qca2
       * qimageblitz 
       * redland
       * strigi
       * soprano
       * tiff
       * update-mime-database
       * windbus
       * zlib ( ported V 1.1.4 )