OLE: Implement undocumented behaviour in DispCallFunc.
Fix DispCallFunc to work with MSDN-undocumented behaviour used by
Office 2003 and document the function.
diff --git a/dlls/oleaut32/typelib.c b/dlls/oleaut32/typelib.c
index 5ed9a82..a6e2495 100644
--- a/dlls/oleaut32/typelib.c
+++ b/dlls/oleaut32/typelib.c
@@ -5173,6 +5173,45 @@
/***********************************************************************
* DispCallFunc (OLEAUT32.@)
+ *
+ * Invokes a function of the specifed calling convention, passing the
+ * specified arguments and returns the result.
+ *
+ * PARAMS
+ * pvInstance [I] Optional pointer to the instance whose function to invoke.
+ * oVft [I] The offset in the vtable. See notes.
+ * cc [I] Calling convention of the function to call.
+ * vtReturn [I] The return type of the function.
+ * cActuals [I] Number of parameters.
+ * prgvt [I] The types of the parameters to pass. This is used for sizing only.
+ * prgpvarg [I] The arguments to pass.
+ * pvargResult [O] The return value of the function. Can be NULL.
+ *
+ * RETURNS
+ * Success: S_OK.
+ * Failure: HRESULT code.
+ *
+ * NOTES
+ * The HRESULT return value of this function is not affected by the return
+ * value of the user supplied function, which is returned in pvargResult.
+ *
+ * If pvInstance is NULL then a non-object function is to be called and oVft
+ * is the address of the function to call.
+ *
+ * The cc parameter can be one of the following values:
+ *|CC_FASTCALL
+ *|CC_CDECL
+ *|CC_PASCAL
+ *|CC_STDCALL
+ *|CC_FPFASTCALL
+ *|CC_SYSCALL
+ *|CC_MPWCDECL
+ *|CC_MPWPASCAL
+ *
+ * BUGS
+ * Native accepts arguments in the reverse order. I.e. the first item in the
+ * prgpvarg array is the last argument in the C/C++ declaration of the
+ * function to be called.
*/
HRESULT WINAPI
DispCallFunc(
@@ -5187,10 +5226,10 @@
pvInstance, oVft, cc, vtReturn, cActuals, prgvt, prgpvarg,
pvargResult, V_VT(pvargResult));
- /* DispCallFunc is only used to invoke methods belonging to an
- * IDispatch-derived COM interface. So we need to add a first parameter
- * to the list of arguments, to supply the interface pointer */
- argsize = 1;
+ argsize = 0;
+ if (pvInstance)
+ argsize++; /* for This pointer */
+
for (i=0;i<cActuals;i++)
{
TRACE("arg %d: type %d, size %d\n",i,prgvt[i],_argsize(prgvt[i]));
@@ -5198,8 +5237,14 @@
argsize += _argsize(prgvt[i]);
}
args = HeapAlloc(GetProcessHeap(),0,sizeof(DWORD)*argsize);
- args[0] = (DWORD)pvInstance; /* this is the fake IDispatch interface pointer */
- argspos = 1;
+
+ argspos = 0;
+ if (pvInstance)
+ {
+ args[0] = (DWORD)pvInstance; /* the This pointer is always the first parameter */
+ argspos++;
+ }
+
for (i=0;i<cActuals;i++)
{
VARIANT *arg = prgpvarg[i];
@@ -5208,7 +5253,16 @@
argspos += _argsize(prgvt[i]);
}
- hres = _invoke((*(FARPROC**)pvInstance)[oVft/sizeof(void *)],cc,argsize,args);
+ if (pvInstance)
+ {
+ FARPROC *vtable = *(FARPROC**)pvInstance;
+ hres = _invoke(vtable[oVft/sizeof(void *)], cc, argsize, args);
+ }
+ else
+ /* if we aren't invoking an object then the function pointer is stored
+ * in oVft */
+ hres = _invoke((FARPROC)oVft, cc, argsize, args);
+
if (pvargResult && (vtReturn != VT_EMPTY))
{
TRACE("Method returned 0x%08lx\n",hres);
