I can't 'HRESULT Authorize()' through 'interface IiTunes' - ios

Question

Good day, everybady,
I work on Windows7 (64 bits) and try use COM / OLE object "iTunesApp Class". This object has installed with iTunes application.
My code is following
HRESULT hr;
CLSID clsid;
IiTunes *pIiTunes = nullptr;
//Apple.iTunes
CLSIDFromProgID(OLESTR("iTunes.Application.1"), &clsid);
hr = CoCreateInstance(clsid, nullptr, CLSCTX_LOCAL_SERVER, __uuidof(IiTunes), reinterpret_cast<LPVOID *>(&pIiTunes));
if (pIiTunes != nullptr)
{
VARIANT data[16];
OLECHAR ver[4096] = L"vaneustroev#gmail.com";
pIiTunes->Authorize(1, data, (BSTR*)ver);
}
Then (pIiTunes->Authorize(1, data, (BSTR*)ver); ) I've got exception '...exception from address 0x000007FEFF4E4FCA (oleaut32.dll) ...Violation of access rights at address 0x000007FEFF4E4FCA...'
I don't know which parameters for pIiTunes->Authorize() I must set

Answer 1

I don't know what is the value of parameters that must be set, but I know the types of these parameters.
First one is a int32, second is a VARIANT reference, third is a array of BSTR. VARIANTs must be initialized and cleared after use, BSTRs must be allocated (a BSTR is not a OLECHAR *) and freed after use.
So, beyond the real semantics of the method, you can call it like this:
VARIANT data;
VariantInit(&data); // undercovers, this will just zero the whole 16-bytes structure
// ... do something with data here
BSTR ver = SysAllocString(L"vaneustroev#gmail.com"); // you should check for null -> out of memory
pIiTunes->Authorize(1, &data, &ver);
// always free BSTRs and clear VARIANTS
SysFreeString(ver);
VariantClear(&data);
If you use Visual Studio, there are cool Compiler COM Support Classes that ease VARIANT and BSTR programming considerably, as you could rewrite all this like this:
_variant_t data;
_bstr_t ver = L"vaneustroev#gmail.com";
BSTR b = ver;
pIiTunes->Authorize(1, &data, &b);
Visual Studio also provides a library called ATL that has other wrappers. Using them is similar:
CComVariant data;
CComBSTR ver = L"vaneustroev#gmail.com";
BSTR b = ver;
pIiTunes->Authorize(1, &data, &b);