Help needed: understanding the DLL

[Commander Bello]

I have a problem understanding how the diplomacy works.

I want to limit some options in diplomacy with the king, here: transporting treasures.

The respective function is:
void CvUnit::kingTransport(bool bSkipPopup)

Spoiler :

void CvUnit::kingTransport(bool bSkipPopup)
{
	if (!canKingTransport())
	{
		return;
	}
	
	if (isHuman() && !bSkipPopup)
	{
		CvDiploParameters* pDiplo = new CvDiploParameters(GET_PLAYER(getOwnerINLINE()).getParent());
		pDiplo->setDiploComment((DiploCommentTypes)GC.getInfoTypeForString("AI_DIPLOCOMMENT_TREASURE_TRANSPORT"));
		pDiplo->setData(getID());
		int iCommission = GC.getDefineINT("KING_TRANSPORT_TREASURE_COMISSION");
		pDiplo->addDiploCommentVariable(iCommission);
		int iAmount = getYieldStored();
		iAmount -= (iAmount * iCommission) / 100;
		iAmount -= (iAmount * GET_PLAYER(getOwnerINLINE()).getTaxRate()) / 100;
		pDiplo->addDiploCommentVariable(iAmount);
		pDiplo->setAIContact(true);
		gDLL->beginDiplomacy(pDiplo, getOwnerINLINE());
	}
	else
	{
		doKingTransport();
	}

Everything upto beginDiplomacy is clear to me (I hope ).

But, the player will have two options: to accept the king's offer or to deny it. If he accepts, I had planned to each time decrease a variable iCounter until iCounter = 0 and accordingly, if he denies, iCounter will stay unchanged.

The definition of beginDiplomacy is in CvDLLUtilityIFaceBase.h and then I am lost.
There isn't a CvDLLUtilityIFaceBase.cpp and looking for calls from or to beginDiplomacy results in either "no function definition found" (calls from) or "no search results" (calls to).

In general, I don't get how the DLL actually does the diplomacy nor where I can find a hook to attach my coding to.

Can any wizard guide me through the night?

Ok, I had a look now from where doKingTransport() will be called. Once it is called from void CvUnit::kingTransport and once from void CvPlayer::handleDiploEvent
Seems that I could hook up there.