I think this is because it is a C++ lib. NativeBoost cannot be used with C++ lib. It is a problem of call convention that is not the same from C to C++. As I discuss with some people it seems be a complexe problem, each C++ compiler seems have it own convention. But Igor can maybe be more accurate about that. A C wrapper to call C++, which should work.
On 23 May 2014, at 02:36, Torsten Bergmann <[email protected]> wrote: > Hi, > > as there was no responded so far I tried to track the problem deeper and did > a short test > client in C/C++ to verify if I can call WKHTMLTOPDF there and generate a PDF > and to > compare to the Pharo/NativeBoost client. > > Attached is the according CPP file which works and results in a PDF with the > google > homepage. > > I also additionally implemented the callback functions in the Pharo wrapper > and > using the error handling I noticed that the component returns "Failed loading > page http:// ..." > > > With that info I compared the C/C++ calls to the Pharo/NativeBoost calls more > deeply and > found out that in C/C++ the following call for an object setting works (by > returning 1): > > > // this returns 1 in C/C++ which is OK > int a = wkhtmltopdf_set_object_setting(os, "page", > "http://www.google.de";); > printf("object set %i",a); > > > while in Pharo the same call fails (by returning 0): > > "The following call failed and returns 0 instead of 1" > self setObjectSetting: 'page' to: 'http://www.google.de' in: os. > > I checked how I wrapped this API call again and again - it is fine from my > side: > > setObjectSetting: aName to: value in: settings > > <primitive: #primitiveNativeCall module: #NativeBoostPlugin> > > ^NBFFICallout stdcall: #(int > wkhtmltopdf_set_object_setting(wkhtmltopdf_object_settings* settings, char* > aName, char* value)) module: 'wkhtmltox.dll' > > and I still have no idea why it fails. > > Especially because "wkhtmltopdf_set_object_setting" function is not different > from "wkhtmltopdf_set_global_setting" which is exactly the same way wrapped, > works > and returns 1 in exactly the same example. > > I would really appreciate if someone could have a second look... > > To reproduce on Windows: > > 1. Download the 32 bit version of WKHTML from http://wkhtmltopdf.org and > install it > 2. Copy the "wkhtmltox.dll" to either the folder of the VM executable > or the Windows directory so it can be found > 3. Load the package WKHTML2PDF-Core-TorstenBergmann.7 > from http://smalltalkhub.com/#!/~TorstenBergmann/WKHTML2PDF into Pharo > 3.0#30848 > 4. Check the Transcript while evaluating: > > WKPDFLibrary example > > One can see that within this code #setObjectSetting:to:in: fails while > #setGlobalSetting:to:in: > works. > > Maybe I just do not see the obvious. Help is appreciated. Thanks in advance! > > bye > T. > > > <main.cpp> Best Regards Jean Baptiste Arnaud [email protected]
