Re: SetWindowTheme() / win2000
On Tue, 2 Oct 2007 22:10:12 -0500, "DR" <dr0134@gmail.com> wrote:
The apps calls the SetWindowTheme() function. To let the app work on
Win2000, I use /DELAYLOAD:Uxtheme.dll and the following code:
#define SkipOnError(x) __try { x; } __except(EXCEPTION_CONTINUE_EXECUTION)
{ ; };
SkipOnError(SetWindowTheme(...));
I wonder if it is correct. I cannot test on Win2000.
Your filter should only accept exceptions that can occur due to delayload
failures. This article contains some code examples demonstrating this:
http://www.microsoft.com/msj/1298/win32/win321298.aspx
You need to look at how its "Figure 2" uses the VcppException macro. That
said, I doubt that trying to continue execution is the right thing to do,
because the assumption is that you've fixed the problem that caused the
exception, such that retrying will succeed. In your case, you haven't, and
it won't. So you need to catch the exception and stop trying to use
delayloaded functions. Below is a class I wrote several years ago to
translate delayload SEs to C++ exceptions:
**********
#include <DelayImp.h>
class DelayLoadSeTranslator
{
public:
DelayLoadSeTranslator();
~DelayLoadSeTranslator();
private:
static void TransFunc(unsigned int, struct _EXCEPTION_POINTERS*);
// Copyguard
DelayLoadSeTranslator(const DelayLoadSeTranslator&);
void operator=(const DelayLoadSeTranslator&);
private: // Data section
_se_translator_function const m_OriginalTransFunc;
};
DelayLoadSeTranslator::DelayLoadSeTranslator()
: m_OriginalTransFunc(_set_se_translator(TransFunc))
{
}
DelayLoadSeTranslator::~DelayLoadSeTranslator()
{
_set_se_translator(m_OriginalTransFunc);
}
void
DelayLoadSeTranslator::TransFunc(
unsigned int code,
struct _EXCEPTION_POINTERS* eps)
{
if (code == VcppException(ERROR_SEVERITY_ERROR, ERROR_MOD_NOT_FOUND))
E::ThrowRuntimeError(
"Could not delayload DLL: ",
reinterpret_cast<DelayLoadInfo*>(
eps->ExceptionRecord->ExceptionInformation[0])->szDll);
if (code == VcppException(ERROR_SEVERITY_ERROR, ERROR_PROC_NOT_FOUND))
E::ThrowRuntimeError(
"Could not delayload API from: ",
reinterpret_cast<DelayLoadInfo*>(
eps->ExceptionRecord->ExceptionInformation[0])->szDll);
}
**********
You will have to supply your own replacement for ThrowRuntimeError, and be
sure to compile the file that contains this code with /EHa. You use the
class like this:
void f()
{
DelayLoadSeTranslator delayTrans;
// Call delay-loaded functions
}
Of course, if you want to handle the error in the function, use try/catch.
--
Doug Harrison
Visual C++ MVP