Updated German translation of the manpage.

[amule.git] / src / UploadQueue.cpp

//
// This file is part of the aMule Project.
//
// Copyright (c) 2003-2011 aMule Team ( admin@amule.org / http://www.amule.org )
// Copyright (c) 2002-2011 Merkur ( devs@emule-project.net / http://www.emule-project.net )
//
// Any parts of this program derived from the xMule, lMule or eMule project,
// or contributed by third-party developers are copyrighted by their
// respective authors.
//
// This program is free software; you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation; either version 2 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program; if not, write to the Free Software
// Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301, USA
//

#include "UploadQueue.h"        // Interface declarations

#include <protocol/Protocols.h>
#include <protocol/ed2k/Client2Client/TCP.h>
#include <common/Macros.h>
#include <common/Constants.h>

#include <cmath>

#include "Types.h"              // Do_not_auto_remove (win32)

#ifdef __WINDOWS__
        #include <winsock.h>    // Do_not_auto_remove
#else
        #include <sys/types.h>  // Do_not_auto_remove
        #include <netinet/in.h> // Do_not_auto_remove
        #include <arpa/inet.h>  // Do_not_auto_remove
#endif

#include "ServerConnect.h"      // Needed for CServerConnect
#include "KnownFile.h"          // Needed for CKnownFile
#include "Packet.h"             // Needed for CPacket
#include "ClientTCPSocket.h"    // Needed for CClientTCPSocket
#include "SharedFileList.h"     // Needed for CSharedFileList
#include "updownclient.h"       // Needed for CUpDownClient
#include "amule.h"              // Needed for theApp
#include "Preferences.h"
#include "ClientList.h"
#include "Statistics.h"         // Needed for theStats
#include "Logger.h"
#include <common/Format.h>
#include "UploadBandwidthThrottler.h"
#include "GuiEvents.h"          // Needed for Notify_*
#include "ListenSocket.h"
#include "DownloadQueue.h"
#include "PartFile.h"


//TODO rewrite the whole networkcode, use overlapped sockets

CUploadQueue::CUploadQueue()
{
        m_nLastStartUpload = 0;
        m_lastSort = 0;
        lastupslotHighID = true;
        m_allowKicking = true;
        m_allUploadingKnownFile = new CKnownFile;
}


void CUploadQueue::SortGetBestClient(CClientRef * bestClient)
{
        uint32 tick = GetTickCount();
        m_lastSort = tick;
        CClientRefList::iterator it = m_waitinglist.begin();
        for (; it != m_waitinglist.end(); ) {
                CClientRefList::iterator it2 = it++;
                CUpDownClient* cur_client = it2->GetClient();

                // clear dead clients
                if (tick - cur_client->GetLastUpRequest() > MAX_PURGEQUEUETIME
                        || !theApp->sharedfiles->GetFileByID(cur_client->GetUploadFileID())) {
                        cur_client->ClearWaitStartTime();
                        RemoveFromWaitingQueue(it2);
                        if (!cur_client->GetSocket()) {
                                if (cur_client->Disconnected(wxT("AddUpNextClient - purged"))) {
                                        cur_client->Safe_Delete();
                                        cur_client = NULL;
                                }
                        }
                        continue;
                }

                if (cur_client->IsBanned() || IsSuspended(cur_client->GetUploadFileID())) { // Banned client or suspended upload ?
                        cur_client->ClearScore();
                        continue;
                }
                // finished clearing

                // Calculate score of current client
                uint32 cur_score = cur_client->CalculateScore();
                // Check if it's better than that of a previous one, and move it up then.
                CClientRefList::iterator it1 = it2;
                while (it1 != m_waitinglist.begin()) {
                        --it1;
                        if (cur_score > it1->GetClient()->GetScore()) {
                                // swap them
                                std::swap(*it2, *it1);
                                --it2;
                        } else {
                                // no need to check further since list is already sorted
                                break;
                        }
                }
        }

        // Second Pass:
        // - calculate queue rank
        // - find best high id client
        // - mark all better low id clients as enabled for upload
        uint16 rank = 1;
        bool bestClientFound = false;
        for (it = m_waitinglist.begin(); it != m_waitinglist.end(); ) {
                CClientRefList::iterator it2 = it++;
                CUpDownClient* cur_client = it2->GetClient();
                cur_client->SetUploadQueueWaitingPosition(rank++);
                if (bestClientFound) {
                        // There's a better high id client
                        cur_client->m_bAddNextConnect = false;
                } else {
                        if (cur_client->HasLowID() && !cur_client->IsConnected()) {
                                // No better high id client, so start upload to this one once it connects
                                cur_client->m_bAddNextConnect = true;
                        } else {
                                // We found a high id client (or a currently connected low id client)
                                bestClientFound = true;
                                cur_client->m_bAddNextConnect = false;
                                if (bestClient) {
                                        bestClient->Link(cur_client CLIENT_DEBUGSTRING("CUploadQueue::SortGetBestClient"));
                                        RemoveFromWaitingQueue(it2);
                                        rank--;
                                        lastupslotHighID = true; // VQB LowID alternate
                                }
                        }
                }
        }

#ifdef __DEBUG__
        AddDebugLogLineN(logLocalClient, CFormat(wxT("Current UL queue (%d):")) % (rank - 1));
        for (it = m_waitinglist.begin(); it != m_waitinglist.end(); ++it) {
                CUpDownClient* c = it->GetClient();
                AddDebugLogLineN(logLocalClient, CFormat(wxT("%4d %7d  %s %5d  %s"))
                        % c->GetUploadQueueWaitingPosition()
                        % c->GetScore()
                        % (c->HasLowID() ? (c->IsConnected() ? wxT("LoCon") : wxT("LowId")) : wxT("High "))
                        % c->ECID()
                        % c->GetUserName()
                        );
        }
#endif  // __DEBUG__
}


void CUploadQueue::AddUpNextClient(CUpDownClient* directadd)
{
        CUpDownClient* newclient = NULL;
        CClientRef newClientRef;
        // select next client or use given client
        if (!directadd) {
                SortGetBestClient(&newClientRef);
                newclient = newClientRef.GetClient();
#if EXTENDED_UPLOADQUEUE
                if (!newclient) {
                        // Nothing to upload. Try to find something from the sources.
                        if (PopulatePossiblyWaitingList() > 0) {
                                newClientRef = * m_possiblyWaitingList.begin();
                                m_possiblyWaitingList.pop_front();
                                newclient = newClientRef.GetClient();
                                AddDebugLogLineN( logLocalClient, wxT("Added client from possiblyWaitingList ") + newclient->GetFullIP() );
                        }
                }
#endif
                if (!newclient) {
                        return;
                }
        } else {
                // Check if requested file is suspended or not shared (maybe deleted recently)

                if (IsSuspended(directadd->GetUploadFileID())
                        || !theApp->sharedfiles->GetFileByID(directadd->GetUploadFileID())) {
                        return;
                } else {
                        newclient = directadd;
                }
        }

        if (IsDownloading(newclient)) {
                return;
        }
        // tell the client that we are now ready to upload
        if (!newclient->IsConnected()) {
                newclient->SetUploadState(US_CONNECTING);
                if (!newclient->TryToConnect(true)) {
                        return;
                }
        } else {
                CPacket* packet = new CPacket(OP_ACCEPTUPLOADREQ, 0, OP_EDONKEYPROT);
                theStats::AddUpOverheadFileRequest(packet->GetPacketSize());
                AddDebugLogLineN( logLocalClient, wxT("Local Client: OP_ACCEPTUPLOADREQ to ") + newclient->GetFullIP() );
                newclient->SendPacket(packet,true);
                newclient->SetUploadState(US_UPLOADING);
        }
        newclient->SetUpStartTime();
        newclient->ResetSessionUp();

        theApp->uploadBandwidthThrottler->AddToStandardList(m_uploadinglist.size(), newclient->GetSocket());
        m_uploadinglist.push_back(CCLIENTREF(newclient, wxT("CUploadQueue::AddUpNextClient")));
        m_allUploadingKnownFile->AddUploadingClient(newclient);
        theStats::AddUploadingClient();

        // Statistic
        CKnownFile* reqfile = const_cast<CKnownFile*>(newclient->GetUploadFile());
        if (reqfile) {
                reqfile->statistic.AddAccepted();
        }

        Notify_SharedCtrlRefreshClient(newclient->ECID(), AVAILABLE_SOURCE);
}

void CUploadQueue::Process()
{
        // Check if someone's waiting, if there is a slot for him,
        // or if we should try to free a slot for him
        uint32 tick = GetTickCount();
        // Nobody waiting or upload started recently
        // (Actually instead of "empty" it should check for "no HighID clients queued",
        //  but the cost for that outweights the benefit. As it is, a slot will be freed
        //  even if it can't be taken because all of the queue is LowID. But just one,
        //  and the kicked client will instantly get it back if he has HighID.)
        // Also, if we are running out of sockets, don't add new clients, but also don't kick existing ones,
        // or uploading will cease right away.
#if EXTENDED_UPLOADQUEUE
        if (tick - m_nLastStartUpload < 1000
#else
        if (m_waitinglist.empty() || tick - m_nLastStartUpload < 1000
#endif
                || theApp->listensocket->TooManySockets()) {
                m_allowKicking = false;
        // Already a slot free, try to fill it
        } else if (m_uploadinglist.size() < GetMaxSlots()) {
                m_allowKicking = false;
                m_nLastStartUpload = tick;
                AddUpNextClient();
        // All slots taken, try to free one
        } else {
                m_allowKicking = true;
        }

        // The loop that feeds the upload slots with data.
        CClientRefList::iterator it = m_uploadinglist.begin();
        while (it != m_uploadinglist.end()) {
                // Get the client. Note! Also updates pos as a side effect.
                CUpDownClient* cur_client = it++->GetClient();

                // It seems chatting or friend slots can get stuck at times in upload.. This needs looked into..
                if (!cur_client->GetSocket()) {
                        RemoveFromUploadQueue(cur_client);
                        if(cur_client->Disconnected(_T("CUploadQueue::Process"))){
                                cur_client->Safe_Delete();
                        }
                } else {
                        cur_client->SendBlockData();
                }
        }

        // Save used bandwidth for speed calculations
        uint64 sentBytes = theApp->uploadBandwidthThrottler->GetNumberOfSentBytesSinceLastCallAndReset();
        (void)theApp->uploadBandwidthThrottler->GetNumberOfSentBytesOverheadSinceLastCallAndReset();

        // Update statistics
        if (sentBytes) {
                theStats::AddSentBytes(sentBytes);
        }

        // Periodically resort queue if it doesn't happen anyway
        if ((sint32) (tick - m_lastSort) > MIN2MS(2)) {
                SortGetBestClient();
        }
}


uint16 CUploadQueue::GetMaxSlots() const
{
        uint16 nMaxSlots = 0;
        float kBpsUpPerClient = (float)thePrefs::GetSlotAllocation();
        if (thePrefs::GetMaxUpload() == UNLIMITED) {
                float kBpsUp = theStats::GetUploadRate() / 1024.0f;
                nMaxSlots = (uint16)(kBpsUp / kBpsUpPerClient) + 2;
        } else {
                if (thePrefs::GetMaxUpload() >= 10) {
                        nMaxSlots = (uint16)floor((float)thePrefs::GetMaxUpload() / kBpsUpPerClient + 0.5);
                                // floor(x + 0.5) is a way of doing round(x) that works with gcc < 3 ...
                        if (nMaxSlots < MIN_UP_CLIENTS_ALLOWED) {
                                nMaxSlots=MIN_UP_CLIENTS_ALLOWED;
                        }
                } else {
                        nMaxSlots = MIN_UP_CLIENTS_ALLOWED;
                }
        }
        if (nMaxSlots > MAX_UP_CLIENTS_ALLOWED) {
                nMaxSlots = MAX_UP_CLIENTS_ALLOWED;
        }
        return nMaxSlots;
}


CUploadQueue::~CUploadQueue()
{
        wxASSERT(m_waitinglist.empty());
        wxASSERT(m_uploadinglist.empty());
        delete m_allUploadingKnownFile;
}


bool CUploadQueue::IsOnUploadQueue(const CUpDownClient* client) const
{
        for (CClientRefList::const_iterator it = m_waitinglist.begin(); it != m_waitinglist.end(); ++it) {
                if (it->GetClient() == client) {
                        return true;
                }
        }
        return false;
}


bool CUploadQueue::IsDownloading(const CUpDownClient* client) const
{
        for (CClientRefList::const_iterator it = m_uploadinglist.begin(); it != m_uploadinglist.end(); ++it) {
                if (it->GetClient() == client) {
                        return true;
                }
        }
        return false;
}


CUpDownClient* CUploadQueue::GetWaitingClientByIP_UDP(uint32 dwIP, uint16 nUDPPort, bool bIgnorePortOnUniqueIP, bool* pbMultipleIPs)
{
        CUpDownClient* pMatchingIPClient = NULL;

        int cMatches = 0;

        CClientRefList::iterator it = m_waitinglist.begin();
        for (; it != m_waitinglist.end(); ++it) {
                CUpDownClient* cur_client = it->GetClient();

                if ((dwIP == cur_client->GetIP()) && (nUDPPort == cur_client->GetUDPPort())) {
                        return cur_client;
                } else if ((dwIP == cur_client->GetIP()) && bIgnorePortOnUniqueIP) {
                        pMatchingIPClient = cur_client;
                        cMatches++;
                }
        }

        if (pbMultipleIPs) {
                *pbMultipleIPs = cMatches > 1;
        }

        if (pMatchingIPClient && cMatches == 1) {
                return pMatchingIPClient;
        } else {
                return NULL;
        }
}


void CUploadQueue::AddClientToQueue(CUpDownClient* client)
{
        if (theApp->serverconnect->IsConnected() && theApp->serverconnect->IsLowID() && !theApp->serverconnect->IsLocalServer(client->GetServerIP(),client->GetServerPort()) && client->GetDownloadState() == DS_NONE && !client->IsFriend() && theStats::GetWaitingUserCount() > 50) {
                // Well, all that issues finish in the same: don't allow to add to the queue
                return;
        }

        if ( client->IsBanned() ) {
                return;
        }

        client->AddAskedCount();
        client->SetLastUpRequest();

        // Find all clients with the same user-hash
        CClientList::SourceList found = theApp->clientlist->GetClientsByHash( client->GetUserHash() );

        CClientList::SourceList::iterator it = found.begin();
        while (it != found.end()) {
                CUpDownClient* cur_client = it++->GetClient();

                if ( IsOnUploadQueue( cur_client ) ) {
                        if ( cur_client == client ) {
                                // This is where LowID clients get their upload slot assigned.
                                // They can't be contacted if they reach top of the queue, so they are just marked for uploading.
                                // When they reconnect next time AddClientToQueue() is called, and they get their slot
                                // through the connection they initiated.
                                // Since at that time no slot is free they get assigned an extra slot,
                                // so then the number of slots exceeds the configured number by one.
                                // To prevent a further increase no more LowID clients get a slot, until
                                // - a HighID client has got one (which happens only after two clients
                                //   have been kicked so a slot is free again)
                                // - or there is a free slot, which means there is no HighID client on queue
                                if (client->m_bAddNextConnect) {
                                        uint16 maxSlots = GetMaxSlots();
                                        if (lastupslotHighID) {
                                                maxSlots++;
                                        }
                                        if (m_uploadinglist.size() < maxSlots) {
                                                client->m_bAddNextConnect = false;
                                                RemoveFromWaitingQueue(client);
                                                AddUpNextClient(client);
                                                lastupslotHighID = false; // LowID alternate
                                                return;
                                        }
                                }

                                client->SendRankingInfo();
                                Notify_SharedCtrlRefreshClient(client->ECID(), AVAILABLE_SOURCE);
                                return;
                        } else {
                                // Hash-clash, remove unidentified clients (possibly both)

                                if ( !cur_client->IsIdentified() ) {
                                        // Cur_client isn't identifed, remove it
                                        theApp->clientlist->AddTrackClient( cur_client );

                                        RemoveFromWaitingQueue( cur_client );
                                        if ( !cur_client->GetSocket() ) {
                                                if (cur_client->Disconnected( wxT("AddClientToQueue - same userhash") ) ) {
                                                        cur_client->Safe_Delete();
                                                }
                                        }
                                }

                                if ( !client->IsIdentified() ) {
                                        // New client isn't identified, remove it
                                        theApp->clientlist->AddTrackClient( client );

                                        if ( !client->GetSocket() ) {
                                                if ( client->Disconnected( wxT("AddClientToQueue - same userhash") ) ) {
                                                        client->Safe_Delete();
                                                }
                                        }

                                        return;
                                }
                        }
                }
        }

        // Count the number of clients with the same IP-address
        found = theApp->clientlist->GetClientsByIP( client->GetIP() );

        int ipCount = 0;
        for ( it = found.begin(); it != found.end(); ++it ) {
                if ( ( it->GetClient() == client ) || IsOnUploadQueue( it->GetClient() ) ) {
                        ipCount++;
                }
        }

        // We do not accept more than 3 clients from the same IP
        if ( ipCount > 3 ) {
                return;
        } else if ( theApp->clientlist->GetClientsFromIP(client->GetIP()) >= 3 ) {
                return;
        }

        // statistic values
        CKnownFile* reqfile = const_cast<CKnownFile*>(client->GetUploadFile());
        if (reqfile) {
                reqfile->statistic.AddRequest();
        }

        if (client->IsDownloading()) {
                // he's already downloading and wants probably only another file
                CPacket* packet = new CPacket(OP_ACCEPTUPLOADREQ, 0, OP_EDONKEYPROT);
                theStats::AddUpOverheadFileRequest(packet->GetPacketSize());
                AddDebugLogLineN( logLocalClient, wxT("Local Client: OP_ACCEPTUPLOADREQ to ") + client->GetFullIP() );
                client->SendPacket(packet,true);
                return;
        }

        // TODO find better ways to cap the list
        if (m_waitinglist.size() >= (thePrefs::GetQueueSize())) {
                return;
        }

        uint32 tick = GetTickCount();
        client->ClearWaitStartTime();
        // if possible start upload right away
        if (m_waitinglist.empty() && tick - m_nLastStartUpload >= 1000
                && m_uploadinglist.size() < GetMaxSlots()
                 && !theApp->listensocket->TooManySockets()) {
                AddUpNextClient(client);
                m_nLastStartUpload = tick;
        } else {
                // add to waiting queue
                m_waitinglist.push_back(CCLIENTREF(client, wxT("CUploadQueue::AddClientToQueue m_waitinglist.push_back")));
                // and sort it to update queue ranks
                SortGetBestClient();
                theStats::AddWaitingClient();
                client->ClearAskedCount();
                client->SetUploadState(US_ONUPLOADQUEUE);
                client->SendRankingInfo();
                //Notify_QlistAddClient(client);
        }
}


bool CUploadQueue::RemoveFromUploadQueue(CUpDownClient* client)
{
        // Keep track of this client
        theApp->clientlist->AddTrackClient(client);

        CClientRefList::iterator it = std::find(m_uploadinglist.begin(),
                m_uploadinglist.end(), CCLIENTREF(client, wxEmptyString));

        if (it != m_uploadinglist.end()) {
                m_uploadinglist.erase(it);
                m_allUploadingKnownFile->RemoveUploadingClient(client);
                theStats::RemoveUploadingClient();
                if( client->GetTransferredUp() ) {
                        theStats::AddSuccessfulUpload();
                        theStats::AddUploadTime(client->GetUpStartTimeDelay() / 1000);
                } else {
                        theStats::AddFailedUpload();
                }
                client->SetUploadState(US_NONE);
                client->ClearUploadBlockRequests();
                return true;
        }

        return false;
}


bool CUploadQueue::CheckForTimeOver(CUpDownClient* client)
{
        // Don't kick anybody if there's no need to
        if (!m_allowKicking) {
                return false;
        }
        // First, check if it is a VIP slot (friend or Release-Prio).
        if (client->GetFriendSlot()) {
                return false;   // never drop the friend
        }
        // Release-Prio and nobody on queue for it?
        if (client->GetUploadFile()->GetUpPriority() == PR_POWERSHARE) {
                // Keep it unless half of the UL slots are occupied with friends or Release uploads.
                uint16 vips = 0;
                for (CClientRefList::iterator it = m_uploadinglist.begin(); it != m_uploadinglist.end(); ++it) {
                        CUpDownClient* cur_client = it->GetClient();
                        if (cur_client->GetFriendSlot() || cur_client->GetUploadFile()->GetUpPriority() == PR_POWERSHARE) {
                                vips++;
                        }
                }
                // allow if VIP uploads occupy at most half of the possible upload slots
                if (vips <= GetMaxSlots() / 2) {
                        return false;
                }
                // Otherwise normal rules apply.
        }

        // Ordinary slots
        // "Transfer full chunks": drop client after 10 MB upload, or after an hour.
        // (so average UL speed should at least be 2.84 kB/s)
        // We don't track what he is downloading, but if it's all from one chunk he gets it.
        if (client->GetUpStartTimeDelay() > 3600000     // time: 1h
                || client->GetSessionUp() > 10485760) {         // data: 10MB
                m_allowKicking = false;         // kick max one client per cycle
                return true;
        }

        return false;
}


/*
 * This function removes a file indicated by filehash from suspended_uploads_list.
 */
void CUploadQueue::ResumeUpload( const CMD4Hash& filehash )
{
        suspendedUploadsSet.erase(filehash);
        AddLogLineN(CFormat( _("Resuming uploads of file: %s" ) )
                                % filehash.Encode() );
}

/*
 * This function stops upload of a file indicated by filehash.
 *
 * a) teminate == false:
 *    File is suspended while a download completes. Then it is resumed after completion,
 *    so it makes sense to keep the client. Such files are kept in suspendedUploadsSet.
 * b) teminate == true:
 *    File is deleted. Then the client is not added to the waiting list.
 *    Waiting clients are swept out with next run of AddUpNextClient,
 *    because their file is not shared anymore.
 */
uint16 CUploadQueue::SuspendUpload(const CMD4Hash& filehash, bool terminate)
{
        AddLogLineN(CFormat( _("Suspending upload of file: %s" ) )
                                % filehash.Encode() );
        uint16 removed = 0;

        //Append the filehash to the list.
        if (!terminate) {
                suspendedUploadsSet.insert(filehash);
        }

        CClientRefList::iterator it = m_uploadinglist.begin();
        while (it != m_uploadinglist.end()) {
                CUpDownClient *potential = it++->GetClient();
                //check if the client is uploading the file we need to suspend
                if (potential->GetUploadFileID() == filehash) {
                        // remove the unlucky client from the upload queue
                        RemoveFromUploadQueue(potential);
                        // if suspend isn't permanent add it to the waiting queue
                        if (terminate) {
                                potential->SetUploadState(US_NONE);
                        } else {
                                m_waitinglist.push_back(CCLIENTREF(potential, wxT("CUploadQueue::SuspendUpload")));
                                theStats::AddWaitingClient();
                                potential->SetUploadState(US_ONUPLOADQUEUE);
                                potential->SendRankingInfo();
                                Notify_SharedCtrlRefreshClient(potential->ECID(), AVAILABLE_SOURCE);
                        }
                        removed++;
                }
        }
        return removed;
}

bool CUploadQueue::RemoveFromWaitingQueue(CUpDownClient* client)
{
        CClientRefList::iterator it = m_waitinglist.begin();

        uint16 rank = 1;
        while (it != m_waitinglist.end()) {
                CClientRefList::iterator it1 = it++;
                if (it1->GetClient() == client) {
                        RemoveFromWaitingQueue(it1);
                        // update ranks of remaining queue
                        while (it != m_waitinglist.end()) {
                                it->GetClient()->SetUploadQueueWaitingPosition(rank++);
                                ++it;
                        }
                        return true;
                }
                rank++;
        }
        return false;
}


void CUploadQueue::RemoveFromWaitingQueue(CClientRefList::iterator pos)
{
        CUpDownClient* todelete = pos->GetClient();
        m_waitinglist.erase(pos);
        theStats::RemoveWaitingClient();
        if( todelete->IsBanned() ) {
                todelete->UnBan();
        }
        //Notify_QlistRemoveClient(todelete);
        todelete->SetUploadState(US_NONE);
        todelete->ClearScore();
        todelete->SetUploadQueueWaitingPosition(0);
}

#if EXTENDED_UPLOADQUEUE

int CUploadQueue::PopulatePossiblyWaitingList()
{
        static uint32 lastPopulate = 0;
        uint32 tick = GetTickCount();
        int ret = m_possiblyWaitingList.size();
        if (tick - lastPopulate > MIN2MS(15)) {
                // repopulate in any case after this time
                m_possiblyWaitingList.clear();
        } else if (ret || tick - lastPopulate < SEC2MS(30)) {
                // don't retry too fast if list is empty
                return ret;
        }
        lastPopulate = tick;

        // Get our downloads
        int nrDownloads = theApp->downloadqueue->GetFileCount();
        for (int idownload = 0; idownload < nrDownloads; idownload++) {
                CPartFile * download = theApp->downloadqueue->GetFileByIndex(idownload);
                if (!download || download->GetAvailablePartCount() == 0) {
                        continue;
                }
                const CKnownFile::SourceSet& sources = download->GetSourceList();
                if (sources.empty()) {
                        continue;
                }
                // Make a table which parts are available. No need to notify a client
                // which needs nothing we have.
                uint16 parts = download->GetPartCount();
                std::vector<bool> partsAvailable;
                partsAvailable.resize(parts);
                for (uint32 i = parts; i--;) {
                        partsAvailable[i] = download->IsComplete(i);
                }
                for (CKnownFile::SourceSet::const_iterator it = sources.begin(); it != sources.end(); it++) {
                        // Iterate over our sources, find those where download == upload
                        CUpDownClient * client = it->GetClient();
                        if (!client || client->GetUploadFile() != download || client->HasLowID()) {
                                continue;
                        }
                        const BitVector& partStatus = client->GetPartStatus();
                        if (partStatus.size() != parts) {
                                continue;
                        }
                        // Do we have something for him?
                        bool haveSomething = false;
                        for (uint32 i = parts; i--;) {
                                if (partsAvailable[i] && !partStatus.get(i)) {
                                        haveSomething = true;
                                        break;
                                }
                        }
                        if (haveSomething) {
                                m_possiblyWaitingList.push_back(*it);
                        }
                }
        }
        ret = m_possiblyWaitingList.size();
        AddDebugLogLineN(logLocalClient, CFormat(wxT("Populated PossiblyWaitingList: %d")) % ret);
        return ret;
}

#endif // EXTENDED_UPLOADQUEUE

// File_checked_for_headers