Help with simple winelib dll

[Seth Burleigh]

Im attempting to build a dll which a windows program running under wine
can dynamically load. The dll will be a wrapper around a linux library.
In preparation ive tried to follow the instructions here
http://www.winehq.org/docs/winelib-guide/bindlls
with a simple example but have not succeeded. Below is the contents of
the files in my directory and the commands i executed. Can anyone help
out? Thanks!

MyLinuxFunc.c
    int MyLinuxFunc(int a,int b) {
    	return a+b;
    }
-----------------------------
MyLinuxFunc.h
    int MyLinuxFunc(int,int);
-----------------------------
libMyLinuxFunc.so
-----------------------------
MyWin.dll.spec
    2 stdcall MyWinFunc (long long) MyProxyWinFunc
-----------------------------
MyWin.c

#include <MyLinuxFunc.h>
    #include <windef.h> 
    int WINAPI MyProxyWinFunc (int a,int b)
    {
     return MyLinuxFunc(a,b);
    }
-----------------------------

winemaker . --nosource-fix --dll --single-target MyWin --nomfc -I"."
-L"." -iMyLinuxFunc

make
winegcc  -o MyWin.so MyLinuxFunc.o MyWin.o    -L.   -lMyLinuxFunc  
MyWin.o: In function `MyProxyWinFunc':
MyWin.c:(.text+0x20): undefined reference to `MyLinuxFunc'
/usr/lib/wine/libwinecrt0.a(exe_main.o): In function `main':
(.text+0xa0): undefined reference to `WinMain'
collect2: ld returned 1 exit status
winegcc: i486-linux-gnu-gcc failed
make: *** [MyWin.so] Error 2

[Seth Shelnutt]

Seth,

Take a look at the source code to the CUDA 3.0 wrapper I just finished. You
have some mistakes in your coding and this should help provide you a better
example. When I first was coding the CUDA 2.0 wrapper some people told me to
look at opengl and how it was wrapper to the linux library so that is how I
came up with this.

http://shelnutt2.host56.com/wrapper.tar.gz

Generally the specfile goes like

@  stdcall cudaGetDeviceProperties( ptr long ) wine_cudaGetDeviceProperties

Then in your .c file:

cudaError_t WINAPI wine_cudaGetDeviceProperties(
struct cudaDeviceProp *prop, int device) {
    WINE_TRACE("\n");
    return cudaGetDeviceProperties(prop, device);
}

Also your linking looks off. You shouldn't be linking -l"." . You need to
specify the exact file, like for CUDA we did -lcudart or -lcufft.

I hope that help you some.

-Seth Shelnutt

On Wed, Jun 16, 2010 at 2:04 AM, Seth Burleigh  wrote:
> Im attempting to build a dll which a windows program running under wine
> can dynamically load. The dll will be a wrapper around a linux library.
> In preparation ive tried to follow the instructions here
> http://www.winehq.org/docs/winelib-guide/bindlls
> with a simple example but have not succeeded. Below is the contents of
> the files in my directory and the commands i executed. Can anyone help
> out? Thanks!
>
> MyLinuxFunc.c
>        int MyLinuxFunc(int a,int b) {
>                return a+b;
>        }
>
> MyLinuxFunc.h
>        int MyLinuxFunc(int,int);
> libMyLinuxFunc.so
>
> MyWin.dll.spec
>    2 stdcall MyWinFunc (long long) MyProxyWinFunc
>
> MyWin.c
>    #include <MyLinuxFunc.h>
>    #include <windef.h>
>    int WINAPI MyProxyWinFunc (int a,int b)
>    {
>     return MyLinuxFunc(a,b);
>    }
>
> winemaker . --nosource-fix --dll --single-target MyWin --nomfc -I"."
> -L"." -iMyLinuxFunc
>
> make
> winegcc  -o MyWin.so MyLinuxFunc.o MyWin.o    -L.   -lMyLinuxFunc
> MyWin.o: In function `MyProxyWinFunc':
> MyWin.c:(.text+0x20): undefined reference to `MyLinuxFunc'
> /usr/lib/wine/libwinecrt0.a(exe_main.o): In function `main':
> (.text+0xa0): undefined reference to `WinMain'
> collect2: ld returned 1 exit status
> winegcc: i486-linux-gnu-gcc failed
> make: *** [MyWin.so] Error 2

[Seth Burleigh]

Thanks, the example helped, i added in the dll main part. But im still
getting the WinMain error and im convinced it has something to do with
how im executing winemaker.

winemaker . --nosource-fix --dll --single-target MyWin --nomfc -I"."
-L"." -iMyLinuxFunc

The new command line result of make is
winegcc -c   -I. -I.   -o MyLinuxFunc.o MyLinuxFunc.c
winegcc -c   -I. -I.   -o MyWin.o MyWin.c
winegcc  -o MyWin.so MyLinuxFunc.o MyWin.o    -L.   -lMyLinuxFunc  
/usr/lib/wine/libwinecrt0.a(exe_main.o): In function `main':
(.text+0xa0): undefined reference to `WinMain'
collect2: ld returned 1 exit status
winegcc: i486-linux-gnu-gcc failed
make: *** [MyWin.so] Error 2

The problem with doing -lMyLinuxFunc (where i have libMyLinuxFunc.so in
the directory) is that for some reason the output i get when doing make
is

seth@seth-laptop:~/devel/meta$ make
winegcc  -o MyWin.so MyLinuxFunc.o MyWin.o    -L. MyLinuxFunc    
winegcc: File does not exist: MyLinuxFunc
make: *** [MyWin.so] Error 2

and the -L. is there to indicate the directory my library is in. Ive
looked up the winmain error and it looks like it appears that im
attempting to build a winmain application instead of a dll? How do i
specify a dll?

Im using wine1.2-dev and wine1.2 (well actually it says to the right
that its 1.1.42 installed version) from the lucid 10.04 ubuntu
repositories.

[Seth Burleigh]

Well, adding the -shared worked! Thanks! Is there any way i can get
winemaker to do this automatically? I thought the -dll option would
work?

[André Hentschel]

Am 16.06.2010 15:50, schrieb Seth Burleigh:
> Thanks, the example helped, i added in the dll main part. But im still
> getting the WinMain error and im convinced it has something to do with
> how im executing winemaker.
>
> winemaker . --nosource-fix --dll --single-target MyWin --nomfc -I"."
> -L"." -iMyLinuxFunc
>
> The new command line result of make is
> winegcc -c   -I. -I.   -o MyLinuxFunc.o MyLinuxFunc.c
> winegcc -c   -I. -I.   -o MyWin.o MyWin.c
> winegcc  -o MyWin.so MyLinuxFunc.o MyWin.o    -L.   -lMyLinuxFunc  
> /usr/lib/wine/libwinecrt0.a(exe_main.o): In function `main':
> (.text+0xa0): undefined reference to `WinMain'
> collect2: ld returned 1 exit status
> winegcc: i486-linux-gnu-gcc failed
> make: *** [MyWin.so] Error 2

The winemaker problem is something for me, i will look into it these days...

[Seth Burleigh]

OK, so i have the dll built. However, it doesn't seem to be able to
open. Let me explain, im using it in metatrader and so all im doing is
moving the dll.so (and renamed it to MyWin.dll) to its libraries folder
and  doing an import statement in mql4. However, i then get a system
error 'Cannot load MyWin.dll (error 126)'. Ive looked it up and that
means 'The specified module could not be found' However, when checking
its dependencies using ldd MyWin.dll, it says it has found all
dependencies. So, is there something i need to do to register the dll so
that it can be loaded properly?

Im assuming metatrader is using a dynamic loading scheme, though i don't
really know.

[André Hentschel]

Am 17.06.2010 04:52, schrieb Seth Burleigh:
> OK, so i have the dll built. However, it doesn't seem to be able to
> open. Let me explain, im using it in metatrader and so all im doing is
> moving the dll.so (and renamed it to MyWin.dll) to its libraries folder
> and  doing an import statement in mql4. However, i then get a system
> error 'Cannot load MyWin.dll (error 126)'. Ive looked it up and that
> means 'The specified module could not be found' However, when checking
> its dependencies using ldd MyWin.dll, it says it has found all
> dependencies. So, is there something i need to do to register the dll so
> that it can be loaded properly?
>
> Im assuming metatrader is using a dynamic loading scheme, though i don't
> really know.

from the spec file there is a def file generated...
change the def-file: replace "LIBRARY MyWin.dll.so" with "LIBRARY MyWin.dll"
the run make again and you should get a dll which might be some more adaptive.

[Seth Burleigh]

Thanks all! I got it to work! There was 2 mistakes with  my thing -
first, i had an empty definition for DllMain which caused the error 126
and then , well, i called the wrong function from metatrader. I shouldve
been calling MyWinFunction. I guess i wasn't doing this because i wasn't
seeing it when doing nm MyWin.dll.so, i guess all that magic is done by
some wine functions in the dll which i see are there!