Method SendNextUDPPacket

src/DownloadQueue.cpp:881–969

bool CDownloadQueue::SendNextUDPPacket()
{
	if ( m_filelist.empty() || !theApp->serverconnect->IsUDPSocketAvailable() || !theApp->IsConnectedED2K()) {
		return false;
	}

	// Start monitoring the server and the files list
	if ( !m_queueServers.IsActive() ) {
		AddObserver( &m_queueFiles );

		theApp->serverlist->AddObserver( &m_queueServers );
	}


	bool packetSent = false;
	while ( !packetSent ) {
		// Get max files ids per packet for current server
		int filesAllowed = GetMaxFilesPerUDPServerPacket();

		if (filesAllowed < 1 || !m_udpserver || IsConnectedServer(m_udpserver)) {
			// Select the next server to ask, must not be the connected server
			do {
				m_udpserver = m_queueServers.GetNext();
			} while (IsConnectedServer(m_udpserver));

			m_cRequestsSentToServer = 0;
			filesAllowed = GetMaxFilesPerUDPServerPacket();
		}


		// Check if we have asked all servers, in which case we are done
		if (m_udpserver == NULL) {
			DoStopUDPRequests();

			return false;
		}

		// Memoryfile containing the hash of every file to request
		// 28bytes allocation because 16b + 4b + 8b is the worse case scenario.
		CMemFile hashlist( 28 );

		CPartFile* file = m_queueFiles.GetNext();

		while ( file && filesAllowed ) {
			uint8 status = file->GetStatus();

			if ( ( status == PS_READY || status == PS_EMPTY ) && file->GetSourceCount() < thePrefs::GetMaxSourcePerFileUDP() ) {
				if (file->IsLargeFile() && !m_udpserver->SupportsLargeFilesUDP()) {
					AddDebugLogLineN(logDownloadQueue, "UDP Request for sources on a large file ignored: server doesn't support it");
				} else {
					++m_cRequestsSentToServer;
					hashlist.WriteHash( file->GetFileHash() );
					// See the notes on TCP packet
					if ( m_udpserver->GetUDPFlags() & SRV_UDPFLG_EXT_GETSOURCES2 ) {
						if (file->IsLargeFile()) {
							wxASSERT(m_udpserver->SupportsLargeFilesUDP());
							hashlist.WriteUInt32( 0 );
							hashlist.WriteUInt64( file->GetFileSize() );