link from a dll to another function in another dll?

[maarten van damme]

Number overflow?
So I implemented the suggested changes (you can check them out at
http://dl.dropbox.com/u/15024434/version2.zip)
But now I get when I compile it :
"kernel32.def(738) : Error 12: Number Overflow: (strange symbol over here)"

I do agree I should've picked a simpler example but I think the
statisfaction will be even bigger if I were to succeed :p

2011/5/1 maarten van damme <maartenvd1994 at gmail.com>

> Wow, thanks for the help
> The first thing I did was in the .di file adding extern(windows){ ... }
> and now compiling doesn't give errors and when examining with dllexp I can
> see that it exports the same functions as the real kernel32.dll :D
>
> Now I'm going to implement all other suggested changes, thanks a lot
>
>
> 2011/4/30 Rainer Schuetze <r.sagitario at gmx.de>
>
>> I'm not sure your wrapping will work with kernel32.dll, but in general
>> here are a few tips:
>>
>> - most functions in the windows API use the __stdcall calling convention
>> in C/C++, which translates to D as "extern(Windows)"
>>
>> - this will usually add the number of bytes passed on the stack as a "@NN"
>> postfix to the function name. This postfix does not exist in kernel32.dll,
>> but in the import library kernel32.lib that you find in the dmd lib folder.
>> Maybe you can use the standard import library, or use the translation shown
>> below.
>>
>> - as the exported function and the function you want to chain to have
>> identical names, you have to change at least one of these and modify them in
>> some build step. I'd suggest to do this in the def file:
>>
>> The symbols in the d-source file containing:
>>
>> ----
>> extern(Windows) HANDLE imported_GetCurrentProcess();
>>
>> export extern(Windows) HANDLE internal_GetCurrentProcess()
>> {
>>  return imported_GetCurrentProcess();
>> }
>> ----
>>
>> can be mapped to other symbols in the def file:
>>
>> ----
>> EXPORTS
>>  GetCurrentProcess = internal_GetCurrentProcess
>>
>> IMPORTS
>>  imported_GetCurrentProcess = kernel33.GetCurrentProcess
>> ----
>>
>> - if you don't know the number of arguments, you should not call the
>> wrapped function, as this will change the callstack. Instead, you should
>> just jump to it:
>>
>> void internal_hread()
>> {
>>  asm
>>  {
>>    naked;
>>    jmp imported_hread;
>>  }
>> }
>>
>> I haven't tried all that, though, so there might be some mistakes...
>>
>> Rainer
>>
>>
>>
>> Denis Koroskin wrote:
>>
>>> On Sat, 30 Apr 2011 13:47:53 +0400, maarten van damme <
>>> maartenvd1994 at gmail.com> wrote:
>>>
>>>  I've changed this, I think I'm still kinda confused with lib files.
>>>> They've
>>>> told me you can't do something with them without a .di file
>>>> So I went ahead and made a kernel33.di file. I now import it in
>>>> kernel32.d
>>>> and my declaration is
>>>> System(C){
>>>> export void * exportedfunctionblablabal(){
>>>>   return exportedfunctionblablablal();
>>>> }
>>>> ...
>>>> }
>>>>
>>>> The file in the directory are:
>>>> kernel32.d : http://dl.dropbox.com/u/15024434/d/kernel32.d
>>>> kernel33.di : http://dl.dropbox.com/u/15024434/d/kernel33.di
>>>> kernel33.lib : http://dl.dropbox.com/u/15024434/d/kernel33.lib
>>>> kernel33.dll : http://dl.dropbox.com/u/15024434/d/kernel33.dll
>>>>
>>>> I've tried to compile using dmd -d kernel32.d kernel33.di kernel33.lib
>>>> but
>>>> it throws errors like
>>>> "Error 42: Symbol undifined _Dkernel1336_hreadfzpV"
>>>> I have literally no clue why this is the case, can someone help me out
>>>> or
>>>> look at the files?
>>>>
>>>> 2011/4/27 maarten van damme <maartenvd1994 at gmail.com>
>>>>
>>>>  I'm afraid I've been a little unclear.
>>>>> I've copied kernel32.dll from the windows dir, renamed it to
>>>>> kernel33.dll
>>>>> and generated a .lib from it using implib.
>>>>> Then I've created a d file with a correct dllmain(stolen from examples)
>>>>> and
>>>>> between
>>>>>
>>>>> system(C){
>>>>> export void * exportedfunctionfromkernel33.dll();
>>>>> export void * exportedfunction2fromkernel33.dll();
>>>>> ...
>>>>> }
>>>>>
>>>>> But it looks like you can't both declare a function from another lib
>>>>> and
>>>>> export it at the same time.
>>>>>
>>>>>
>>> In your kernel33.di, try making it extern (C) export void* _hread(); etc.
>>> You functions get D mangling otherwise.
>>>
>>> I'd also suggest you to start with a less complex example, e.g. export
>>> only one function, make sure it works, then add the rest.
>>>
>>> If you think your .lib files doesn't do its job, try using .def file
>>> instead. I find them extremely helpful, and they are a lot easier to
>>> edit/extend.
>>>
>>> Hope that helps.
>>>
>>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.puremagic.com/pipermail/digitalmars-d/attachments/20110501/a9a846da/attachment.html>