[Shapelib] Re: shapelib improvements

[Tom Kazimiers]

Mateusz Loskot schrieb:
> Tom Kazimiers wrote:
>   
>>> Bram de Greve wrote:
>>>       
>>>> Mateusz Loskot wrote:
>>>>         
>>>>> Possible solution is to use Unicode-aware API availalbe on 
>>>>> Windows: _wfopen() (or CreateFile) Some time ago I ported
>>>>> Shapelib to use wide-character versions of I/O functions as I
>>>>> needed it on Windows CE (Unicode-only system).
>>>>>
>>>>> Unfortunately, I have lost these modifications but it isn't a
>>>>> big deal to do it.
>>>>>           
>>>> I've done similar modification for pyshapelib (I choose _wfopen
>>>> because that's similar to what Python does), but as Frank is
>>>> going to implement CreateFile IO hooks anyway, I think we can
>>>> rely on that.  As long as he uses the Unicode versions of it,
>>>> that is =).
>>>>         
>>> Yes, I think so too.
>>>       
>> I had this problem, too, as I needed to use this lib on win CE. And
>> ported shapelib to unicode. If you want, I can send the sources.
>>     
>
> Tom,
>
> Perhaps we could make a unicode branch of Shapelib.
> Frank's opinion is most important here, not mine
>   
This would be a good thing!

>>>> However, it still isn't without issues:
>>>>
>>>> The CreateFile IO hooks will still accept char* filenames, which
>>>> would be OK if we would treat it as UTF-8 and decode it with 
>>>> MultyByteToWideChar.  But that would cause an assymetry with the 
>>>> (default) tradition IO hooks that use fopen and still treats the
>>>> char* filenames as ANSI encoded (in whatever codepage is set by
>>>> the regionale).  If it looks like a duck ...
>>>>         
>>> Right, there is some inconsistency. However, I can't see any better
>>> option.
>>>       
>> But if you use shapelib as a dll from another program, esp. a managed
>> code one (I use C#) - on windows CE you have the only option to call
>> with unicode parameters. This means you have to write wrappers which
>> to the transformation or one makes the dll unicode aware (this is
>> what I did). Are there any ways to get a managed to unmanaged call on
>> Win CE working with char?
>>     
>
> Doesn't marchaling to UnmanagedType.LPStr work?
> Also, CharSet attribute of DLLImport to control how encoding information
> is marshalled. CharSet.Ansi is default for C++, so Unicode->ANSI is
> translated automatically.
>
> Cheers
>   

Sure it is on a "normal" desktop computer - but in Win CE environment
one can only choose CharSet.Unicode as the whole OS works only with unicode.
The UnmanagedType.LPStr I did not try out - I will test it. But since I
have read that Win CE can only handle unicode I doupt it  would work.

Bye