C++ CUInt128::Xor方法代码示例

void CRoutingZone::DbgWriteBootstrapFile()
{
	DebugLogWarning(_T("Writing special bootstrap nodes.dat - not intended for normal use"));
	try
	{
		// Write a saved contact list.
		CUInt128 uID;
		CSafeBufferedFile file;
		CFileException fexp;
		if (file.Open(m_sFilename, CFile::modeWrite | CFile::modeCreate | CFile::typeBinary|CFile::shareDenyWrite, &fexp))
		{
			setvbuf(file.m_pStream, NULL, _IOFBF, 32768);

			// The bootstrap method gets a very nice sample of contacts to save.
			ContactMap mapContacts;
			CUInt128 uRandom(CUInt128((ULONG)0), 0);
			CUInt128 uDistance = uRandom;
			uDistance.Xor(uMe);
			GetClosestTo(2, uRandom, uDistance, 1200, &mapContacts, false, false);
			// filter out Kad1 nodes
			for (ContactMap::iterator itContactMap = mapContacts.begin(); itContactMap != mapContacts.end(); )
			{
				ContactMap::iterator itCurContactMap = itContactMap;
				++itContactMap;
				CContact* pContact = itCurContactMap->second;
				if (pContact->GetVersion() <= 1)
					mapContacts.erase(itCurContactMap);
			}
			// Start file with 0 to prevent older clients from reading it.
			file.WriteUInt32(0);
			// Now tag it with a version which happens to be 2 (1 till 0.48a).
			file.WriteUInt32(3);
			file.WriteUInt32(1); // if we would use version >=3, this would mean that this is not a normal nodes.dat
			file.WriteUInt32((uint32_t)mapContacts.size());
			for (ContactMap::const_iterator itContactMap = mapContacts.begin(); itContactMap != mapContacts.end(); ++itContactMap)
			{
				CContact* pContact = itContactMap->second;
				pContact->GetClientID(&uID);
				file.WriteUInt128(&uID);
				file.WriteUInt32(pContact->GetIPAddress());
				file.WriteUInt16(pContact->GetUDPPort());
				file.WriteUInt16(pContact->GetTCPPort());
				file.WriteUInt8(pContact->GetVersion());
			}
			file.Close();
			AddDebugLogLine( false, _T("Wrote %ld contact to bootstrap file."), mapContacts.size());
		}
		else
			DebugLogError(_T("Unable to store Kad file: %s"), m_sFilename);
	}
	catch (CFileException* e)
	{
		e->Delete();
		AddDebugLogLine(false, _T("CFileException in CRoutingZone::writeFile"));
	}

}

CContact *CRoutingZone::GetContact(const CUInt128 &uID) const
{
	if (IsLeaf())
		return m_pBin->GetContact(uID);
	else{
		CUInt128 uDistance;
		CKademlia::GetPrefs()->GetKadID(&uDistance);
		uDistance.Xor(uID);
		return m_pSubZones[uDistance.GetBitNumber(m_uLevel)]->GetContact(uID);
	}
}

void CRoutingZone::ReadBootstrapNodesDat(CFileDataIO& file){
	// Bootstrap versions of nodes.dat files, are in the style of version 1 nodes.dats. The difference is that
	// they will contain more contacts 500-1000 instead 50, and those contacts are not added into the routingtable
	// but used to sent Bootstrap packets too. The advantage is that on a list with a high ratio of dead nodes,
	// we will be able to bootstrap faster than on a normal nodes.dat and more important, if we would deliver
	// a normal nodes.dat with eMule, those 50 nodes would be kinda DDOSed because everyone adds them to their routing
	// table, while with this style, we don't actually add any of the contacts to our routing table in the end and we
	// ask only one of those 1000 contacts one time (well or more untill we find an alive one).
	if (!CKademlia::s_liBootstapList.IsEmpty()){
		ASSERT( false );
		return;
	}
	uint32_t uNumContacts = file.ReadUInt32();
	if (uNumContacts != 0 && uNumContacts * 25 == (file.GetLength() - file.GetPosition()))
	{
		uint32_t uValidContacts = 0;
		CUInt128 uID;
		while ( uNumContacts )
		{
			file.ReadUInt128(&uID);
			uint32_t uIP = file.ReadUInt32();
			uint16_t uUDPPort = file.ReadUInt16();
			uint16_t uTCPPort = file.ReadUInt16();
			uint8_t uContactVersion = file.ReadUInt8();

			uint32_t uhostIP = ntohl(uIP);
			if (::IsGoodIPPort(uhostIP, uUDPPort))
			{
				if (::theApp.ipfilter->IsFiltered(uhostIP))
				{
					if (::thePrefs.GetLogFilteredIPs())
						AddDebugLogLine(false, _T("Ignored kad contact (IP=%s:%u)--read known.dat -- - IP filter (%s)") , ipstr(uhostIP), uUDPPort, ::theApp.ipfilter->GetLastHit());
				}
				else if (uUDPPort == 53 && uContactVersion <= KADEMLIA_VERSION5_48a) 
				{
					if (::thePrefs.GetLogFilteredIPs())
						AddDebugLogLine(false, _T("Ignored kad contact (IP=%s:%u)--read known.dat") , ipstr(uhostIP), uUDPPort);
				}
				else if (uContactVersion > 1) // only kad2 nodes
				{
					// we want the 50 nodes closest to our own ID (provides randomness between different users and gets has good chances to get a bootstrap with close Nodes which is a nice start for our routing table) 
					CUInt128 uDistance = uMe;
					uDistance.Xor(uID);
					uValidContacts++;
					// don't bother if we already have 50 and the farest distance is smaller than this contact
					if (CKademlia::s_liBootstapList.GetCount() < 50 || CKademlia::s_liBootstapList.GetTail()->GetDistance() > uDistance){
						// look were to put this contact into the proper position
						bool bInserted = false;
						CContact* pContact = new CContact(uID, uIP, uUDPPort, uTCPPort, uMe, uContactVersion, 0, false);
						for (POSITION pos = CKademlia::s_liBootstapList.GetHeadPosition(); pos != NULL; CKademlia::s_liBootstapList.GetNext(pos)){
							if (CKademlia::s_liBootstapList.GetAt(pos)->GetDistance() > uDistance){
								CKademlia::s_liBootstapList.InsertBefore(pos, pContact);
								bInserted = true;
								break;
							}
						}
						if (!bInserted){
							ASSERT( CKademlia::s_liBootstapList.GetCount() < 50 );
							CKademlia::s_liBootstapList.AddTail(pContact);
						}
						else if (CKademlia::s_liBootstapList.GetCount() > 50)
							delete CKademlia::s_liBootstapList.RemoveTail();
					}
				}
			}
			uNumContacts--;
		}
		AddLogLine( false, GetResString(IDS_KADCONTACTSREAD), CKademlia::s_liBootstapList.GetCount());
		DebugLog(_T("Loaded Bootstrap nodes.dat, selected %u out of %u valid contacts"), CKademlia::s_liBootstapList.GetCount(), uValidContacts);
	}
}