// Copyright (c) 2009-2010 Satoshi Nakamoto
// Copyright (c) 2009-2012 The Bitcoin developers
// Distributed under the MIT/X11 software license, see the accompanying
// file COPYING or http://www.opensource.org/licenses/mit-license.php.

#include "irc.h"
#include "db.h"
#include "net.h"
#include "init.h"
#include "addrman.h"
#include "ui_interface.h"
#include "miner.h"
#include "ntp.h"

#ifdef WIN32
#include <string.h>
#endif

using namespace std;
using namespace boost;

static const int MAX_OUTBOUND_CONNECTIONS = 16;

void ThreadMessageHandler2(void* parg);
void ThreadSocketHandler2(void* parg);
void ThreadOpenConnections2(void* parg);
void ThreadOpenAddedConnections2(void* parg);
void ThreadDNSAddressSeed2(void* parg);

// Fix for ancient MinGW versions, that don't have defined these in ws2tcpip.h.
// Todo: Can be removed when our pull-tester is upgraded to a modern MinGW version.
#ifdef WIN32
#ifndef PROTECTION_LEVEL_UNRESTRICTED
#define PROTECTION_LEVEL_UNRESTRICTED 10
#endif
#ifndef IPV6_PROTECTION_LEVEL
#define IPV6_PROTECTION_LEVEL 23
#endif
#endif

struct LocalServiceInfo {
    int nScore;
    uint16_t nPort;
};

//
// Global state variables
//
bool fClient = false;
bool fDiscover = true;
uint64_t nLocalServices = (fClient ? 0 : NODE_NETWORK);
static CCriticalSection cs_mapLocalHost;
static map<CNetAddr, LocalServiceInfo> mapLocalHost;
static bool vfReachable[NET_MAX] = {};
static bool vfLimited[NET_MAX] = {};
static CNode* pnodeLocalHost = NULL;
static CNode* pnodeSync = NULL;
CAddress addrSeenByPeer(CService("0.0.0.0", nPortZero), nLocalServices);
uint64_t nLocalHostNonce = 0;
boost::array<int, THREAD_MAX> vnThreadsRunning;
static std::vector<SOCKET> vhListenSocket;
CAddrMan addrman;

vector<CNode*> vNodes;
CCriticalSection cs_vNodes;
map<CInv, CDataStream> mapRelay;
deque<pair<int64_t, CInv> > vRelayExpiration;
CCriticalSection cs_mapRelay;
map<CInv, int64_t> mapAlreadyAskedFor;

static deque<string> vOneShots;
CCriticalSection cs_vOneShots;

set<CNetAddr> setservAddNodeAddresses;
CCriticalSection cs_setservAddNodeAddresses;

vector<std::string> vAddedNodes;
CCriticalSection cs_vAddedNodes;

static CSemaphore *semOutbound = NULL;

void AddOneShot(string strDest)
{
    LOCK(cs_vOneShots);
    vOneShots.push_back(strDest);
}

unsigned short GetListenPort()
{
    return (unsigned short)(GetArg("-port", GetDefaultPort()));
}

void CNode::PushGetBlocks(CBlockIndex* pindexBegin, uint256 hashEnd)
{
    // Filter out duplicate requests
    if (pindexBegin == pindexLastGetBlocksBegin && hashEnd == hashLastGetBlocksEnd)
        return;
    pindexLastGetBlocksBegin = pindexBegin;
    hashLastGetBlocksEnd = hashEnd;

    PushMessage("getblocks", CBlockLocator(pindexBegin), hashEnd);
}

// find 'best' local address for a particular peer
bool GetLocal(CService& addr, const CNetAddr *paddrPeer)
{
    if (fNoListen)
        return false;

    int nBestScore = -1;
    int nBestReachability = -1;
    {
        LOCK(cs_mapLocalHost);
        for (map<CNetAddr, LocalServiceInfo>::iterator it = mapLocalHost.begin(); it != mapLocalHost.end(); it++)
        {
            int nScore = (*it).second.nScore;
            int nReachability = (*it).first.GetReachabilityFrom(paddrPeer);
            if (nReachability > nBestReachability || (nReachability == nBestReachability && nScore > nBestScore))
            {
                addr = CService((*it).first, (*it).second.nPort);
                nBestReachability = nReachability;
                nBestScore = nScore;
            }
        }
    }
    return nBestScore >= 0;
}

// get best local address for a particular peer as a CAddress
CAddress GetLocalAddress(const CNetAddr *paddrPeer)
{
    CAddress ret(CService("0.0.0.0", nPortZero), 0);
    CService addr;
    if (GetLocal(addr, paddrPeer))
    {
        ret = CAddress(addr);
        ret.nServices = nLocalServices;
        ret.nTime = GetAdjustedTime();
    }
    return ret;
}

bool RecvLine(SOCKET hSocket, string& strLine)
{
    strLine = "";
    for ( ; ; )
    {
        char c;
        int nBytes = recv(hSocket, &c, 1, 0);
        if (nBytes > 0)
        {
            if (c == '\n')
                continue;
            if (c == '\r')
                return true;
            strLine += c;
            if (strLine.size() >= 9000)
                return true;
        }
        else if (nBytes <= 0)
        {
            if (fShutdown)
                return false;
            if (nBytes < 0)
            {
                int nErr = WSAGetLastError();
                if (nErr == WSAEMSGSIZE)
                    continue;
                if (nErr == WSAEWOULDBLOCK || nErr == WSAEINTR || nErr == WSAEINPROGRESS)
                {
                    Sleep(10);
                    continue;
                }
            }
            if (!strLine.empty())
                return true;
            if (nBytes == 0)
            {
                // socket closed
                printf("socket closed\n");
                return false;
            }
            else
            {
                // socket error
                int nErr = WSAGetLastError();
                printf("recv failed: %d\n", nErr);
                return false;
            }
        }
    }
}

// used when scores of local addresses may have changed
// pushes better local address to peers
void static AdvertizeLocal()
{
    LOCK(cs_vNodes);
    BOOST_FOREACH(CNode* pnode, vNodes)
    {
        if (pnode->fSuccessfullyConnected)
        {
            CAddress addrLocal = GetLocalAddress(&pnode->addr);
            if (addrLocal.IsRoutable() && (CService)addrLocal != pnode->addrLocal)
            {
                pnode->PushAddress(addrLocal);
                pnode->addrLocal = addrLocal;
            }
        }
    }
}

void SetReachable(enum Network net, bool fFlag)
{
    LOCK(cs_mapLocalHost);
    vfReachable[net] = fFlag;
    if (net == NET_IPV6 && fFlag)
        vfReachable[NET_IPV4] = true;
}

// learn a new local address
bool AddLocal(const CService& addr, int nScore)
{
    if (!addr.IsRoutable())
        return false;

    if (!fDiscover && nScore < LOCAL_MANUAL)
        return false;

    if (IsLimited(addr))
        return false;

    printf("AddLocal(%s,%i)\n", addr.ToString().c_str(), nScore);

    {
        LOCK(cs_mapLocalHost);
        bool fAlready = mapLocalHost.count(addr) > 0;
        LocalServiceInfo &info = mapLocalHost[addr];
        if (!fAlready || nScore >= info.nScore) {
            info.nScore = nScore + (fAlready ? 1 : 0);
            info.nPort = addr.GetPort();
        }
        SetReachable(addr.GetNetwork());
    }

    AdvertizeLocal();

    return true;
}

bool AddLocal(const CNetAddr &addr, int nScore)
{
    return AddLocal(CService(addr, GetListenPort()), nScore);
}

/** Make a particular network entirely off-limits (no automatic connects to it) */
void SetLimited(enum Network net, bool fLimited)
{
    if (net == NET_UNROUTABLE)
        return;
    LOCK(cs_mapLocalHost);
    vfLimited[net] = fLimited;
}

bool IsLimited(enum Network net)
{
    LOCK(cs_mapLocalHost);
    return vfLimited[net];
}

bool IsLimited(const CNetAddr &addr)
{
    return IsLimited(addr.GetNetwork());
}

/** vote for a local address */
bool SeenLocal(const CService& addr)
{
    {
        LOCK(cs_mapLocalHost);
        if (mapLocalHost.count(addr) == 0)
            return false;
        mapLocalHost[addr].nScore++;
    }

    AdvertizeLocal();

    return true;
}

/** check whether a given address is potentially local */
bool IsLocal(const CService& addr)
{
    LOCK(cs_mapLocalHost);
    return mapLocalHost.count(addr) > 0;
}

/** check whether a given address is in a network we can probably connect to */
bool IsReachable(const CNetAddr& addr)
{
    LOCK(cs_mapLocalHost);
    enum Network net = addr.GetNetwork();
    return vfReachable[net] && !vfLimited[net];
}

extern int GetExternalIPbySTUN(uint64_t rnd, struct sockaddr_in *mapped, const char **srv);

// We now get our external IP from the IRC server first and only use this as a backup
bool GetMyExternalIP(CNetAddr& ipRet)
{
    struct sockaddr_in mapped;
    uint64_t rnd = std::numeric_limits<uint64_t>::max();
    const char *srv;
    int rc = GetExternalIPbySTUN(rnd, &mapped, &srv);
    if(rc >= 0) {
        ipRet = CNetAddr(mapped.sin_addr);
        printf("GetExternalIPbySTUN(%" PRIu64 ") returned %s in attempt %d; Server=%s\n", rnd, ipRet.ToStringIP().c_str(), rc, srv);
        return true;
    }
    return false;
}

void ThreadGetMyExternalIP(void* parg)
{
    // Make this thread recognisable as the external IP detection thread
    RenameThread("novacoin-ext-ip");

    CNetAddr addrLocalHost;
    if (GetMyExternalIP(addrLocalHost))
    {
        printf("GetMyExternalIP() returned %s\n", addrLocalHost.ToStringIP().c_str());
        AddLocal(addrLocalHost, LOCAL_HTTP);
    }
}





void AddressCurrentlyConnected(const CService& addr)
{
    addrman.Connected(addr);
}




uint64_t CNode::nTotalBytesRecv = 0;
uint64_t CNode::nTotalBytesSent = 0;
CCriticalSection CNode::cs_totalBytesRecv;
CCriticalSection CNode::cs_totalBytesSent;

CNode* FindNode(const CNetAddr& ip)
{
    LOCK(cs_vNodes);
    BOOST_FOREACH(CNode* pnode, vNodes)
        if ((CNetAddr)pnode->addr == ip)
            return (pnode);
    return NULL;
}

CNode* FindNode(std::string addrName)
{
    LOCK(cs_vNodes);
    BOOST_FOREACH(CNode* pnode, vNodes)
        if (pnode->addrName == addrName)
            return (pnode);
    return NULL;
}

CNode* FindNode(const CService& addr)
{
    LOCK(cs_vNodes);
    BOOST_FOREACH(CNode* pnode, vNodes)
        if ((CService)pnode->addr == addr)
            return (pnode);
    return NULL;
}

CNode* ConnectNode(CAddress addrConnect, const char *pszDest, int64_t nTimeout)
{
    if (pszDest == NULL) {
        if (IsLocal(addrConnect))
            return NULL;

        // Look for an existing connection
        CNode* pnode = FindNode((CService)addrConnect);
        if (pnode)
        {
            if (nTimeout != 0)
                pnode->AddRef(nTimeout);
            else
                pnode->AddRef();
            return pnode;
        }
    }


    /// debug print
    printf("trying connection %s lastseen=%.1fhrs\n",
        pszDest ? pszDest : addrConnect.ToString().c_str(),
        pszDest ? 0 : (double)(GetAdjustedTime() - addrConnect.nTime)/3600.0);

    // Connect
    SOCKET hSocket;
    if (pszDest ? ConnectSocketByName(addrConnect, hSocket, pszDest, GetDefaultPort()) : ConnectSocket(addrConnect, hSocket))
    {
        addrman.Attempt(addrConnect);

        /// debug print
        printf("connected %s\n", pszDest ? pszDest : addrConnect.ToString().c_str());

        // Set to non-blocking
#ifdef WIN32
        u_long nOne = 1;
        if (ioctlsocket(hSocket, FIONBIO, &nOne) == SOCKET_ERROR)
            printf("ConnectSocket() : ioctlsocket non-blocking setting failed, error %d\n", WSAGetLastError());
#else
        if (fcntl(hSocket, F_SETFL, O_NONBLOCK) == SOCKET_ERROR)
            printf("ConnectSocket() : fcntl non-blocking setting failed, error %d\n", errno);
#endif

        // Add node
        CNode* pnode = new CNode(hSocket, addrConnect, pszDest ? pszDest : "", false);
        if (nTimeout != 0)
            pnode->AddRef(nTimeout);
        else
            pnode->AddRef();

        {
            LOCK(cs_vNodes);
            vNodes.push_back(pnode);
        }

        pnode->nTimeConnected = GetTime();
        return pnode;
    }
    else
    {
        return NULL;
    }
}

void CNode::CloseSocketDisconnect()
{
    fDisconnect = true;
    if (hSocket != INVALID_SOCKET)
    {
        printf("disconnecting node %s\n", addrName.c_str());
        CloseSocket(hSocket);
        vRecv.clear();
    }

    // in case this fails, we'll empty the recv buffer when the CNode is deleted
    TRY_LOCK(cs_vRecv, lockRecv);
    if (lockRecv)
        vRecv.clear();

    // if this was the sync node, we'll need a new one
    if (this == pnodeSync)
        pnodeSync = NULL;
}

void CNode::Cleanup()
{
}


void CNode::PushVersion()
{
    int64_t nTime = GetAdjustedTime();
    CAddress addrYou, addrMe;

    bool fHidden = false;
    if (addr.IsTor()) {
        if (mapArgs.count("-torname")) {
            // Our hidden service address
            CService addrTorName(mapArgs["-torname"], GetListenPort());

            if (addrTorName.IsValid()) {
                addrYou = addr;
                addrMe = CAddress(addrTorName);
                fHidden = true;
            }
        }
    }

    if (!fHidden) {
        addrYou = (addr.IsRoutable() && !IsProxy(addr) ? addr : CAddress(CService("0.0.0.0", nPortZero)));
        addrMe = GetLocalAddress(&addr);
    }

    RAND_bytes((unsigned char*)&nLocalHostNonce, sizeof(nLocalHostNonce));
    printf("send version message: version %d, blocks=%d, us=%s, them=%s, peer=%s\n", PROTOCOL_VERSION, nBestHeight, addrMe.ToString().c_str(), addrYou.ToString().c_str(), addr.ToString().c_str());
    PushMessage("version", PROTOCOL_VERSION, nLocalServices, nTime, addrYou, addrMe,
                nLocalHostNonce, FormatSubVersion(CLIENT_NAME, CLIENT_VERSION, std::vector<string>()), nBestHeight);
}





std::map<CNetAddr, int64_t> CNode::setBanned;
CCriticalSection CNode::cs_setBanned;

void CNode::ClearBanned()
{
    setBanned.clear();
}

bool CNode::IsBanned(CNetAddr ip)
{
    bool fResult = false;
    {
        LOCK(cs_setBanned);
        std::map<CNetAddr, int64_t>::iterator i = setBanned.find(ip);
        if (i != setBanned.end())
        {
            int64_t t = (*i).second;
            if (GetTime() < t)
                fResult = true;
        }
    }
    return fResult;
}

bool CNode::Misbehaving(int howmuch)
{
    if (addr.IsLocal())
    {
        printf("Warning: Local node %s misbehaving (delta: %d)!\n", addrName.c_str(), howmuch);
        return false;
    }

    nMisbehavior += howmuch;
    if (nMisbehavior >= GetArgInt("-banscore", 100))
    {
        int64_t banTime = GetTime()+GetArg("-bantime", nOneDay);  // Default 24-hour ban
        printf("Misbehaving: %s (%d -> %d) DISCONNECTING\n", addr.ToString().c_str(), nMisbehavior-howmuch, nMisbehavior);
        {
            LOCK(cs_setBanned);
            if (setBanned[addr] < banTime)
                setBanned[addr] = banTime;
        }
        CloseSocketDisconnect();
        return true;
    } else
        printf("Misbehaving: %s (%d -> %d)\n", addr.ToString().c_str(), nMisbehavior-howmuch, nMisbehavior);
    return false;
}

#undef X
#define X(name) stats.name = name
void CNode::copyStats(CNodeStats &stats)
{
    X(nServices);
    X(nLastSend);
    X(nLastRecv);
    X(nTimeConnected);
    X(addrName);
    X(nVersion);
    X(strSubVer);
    X(fInbound);
    X(nReleaseTime);
    X(nStartingHeight);
    X(nMisbehavior);
    X(nSendBytes);
    X(nRecvBytes);
    stats.fSyncNode = (this == pnodeSync);
}
#undef X

void Release(CNode* node) {
    node->Release();
}





void ThreadSocketHandler(void* parg)
{
    // Make this thread recognisable as the networking thread
    RenameThread("novacoin-net");

    try
    {
        vnThreadsRunning[THREAD_SOCKETHANDLER]++;
        ThreadSocketHandler2(parg);
        vnThreadsRunning[THREAD_SOCKETHANDLER]--;
    }
    catch (std::exception& e) {
        vnThreadsRunning[THREAD_SOCKETHANDLER]--;
        PrintException(&e, "ThreadSocketHandler()");
    } catch (...) {
        vnThreadsRunning[THREAD_SOCKETHANDLER]--;
        throw; // support pthread_cancel()
    }
    printf("ThreadSocketHandler exited\n");
}

static list<CNode*> vNodesDisconnected;

void ThreadSocketHandler2(void* parg)
{
    printf("ThreadSocketHandler started\n");
    size_t nPrevNodeCount = 0;
    for ( ; ; )
    {
        //
        // Disconnect nodes
        //
        {
            LOCK(cs_vNodes);
            // Disconnect unused nodes
            vector<CNode*> vNodesCopy = vNodes;
            BOOST_FOREACH(CNode* pnode, vNodesCopy)
            {
                if (pnode->fDisconnect ||
                    (pnode->GetRefCount() <= 0 && pnode->vRecv.empty() && pnode->vSend.empty()))
                {
                    // remove from vNodes
                    vNodes.erase(remove(vNodes.begin(), vNodes.end(), pnode), vNodes.end());

                    // release outbound grant (if any)
                    pnode->grantOutbound.Release();

                    // close socket and cleanup
                    pnode->CloseSocketDisconnect();
                    pnode->Cleanup();

                    // hold in disconnected pool until all refs are released
                    pnode->nReleaseTime = max(pnode->nReleaseTime, GetTime() + 15 * 60);
                    if (pnode->fNetworkNode || pnode->fInbound)
                        pnode->Release();
                    vNodesDisconnected.push_back(pnode);
                }
            }

            // Delete disconnected nodes
            list<CNode*> vNodesDisconnectedCopy = vNodesDisconnected;
            BOOST_FOREACH(CNode* pnode, vNodesDisconnectedCopy)
            {
                // wait until threads are done using it
                if (pnode->GetRefCount() <= 0)
                {
                    bool fDelete = false;
                    {
                        TRY_LOCK(pnode->cs_vSend, lockSend);
                        if (lockSend)
                        {
                            TRY_LOCK(pnode->cs_vRecv, lockRecv);
                            if (lockRecv)
                            {
                                TRY_LOCK(pnode->cs_mapRequests, lockReq);
                                if (lockReq)
                                {
                                    TRY_LOCK(pnode->cs_inventory, lockInv);
                                    if (lockInv)
                                        fDelete = true;
                                }
                            }
                        }
                    }
                    if (fDelete)
                    {
                        vNodesDisconnected.remove(pnode);
                        delete pnode;
                    }
                }
            }
        }
        if (vNodes.size() != nPrevNodeCount)
        {
            nPrevNodeCount = vNodes.size();
            uiInterface.NotifyNumConnectionsChanged(vNodes.size());
        }


        //
        // Find which sockets have data to receive
        //
        struct timeval timeout;
        timeout.tv_sec  = 0;
        timeout.tv_usec = 50000; // frequency to poll pnode->vSend

        fd_set fdsetRecv;
        fd_set fdsetSend;
        fd_set fdsetError;
        FD_ZERO(&fdsetRecv);
        FD_ZERO(&fdsetSend);
        FD_ZERO(&fdsetError);
        SOCKET hSocketMax = 0;
        bool have_fds = false;

        BOOST_FOREACH(SOCKET hListenSocket, vhListenSocket) {
            FD_SET(hListenSocket, &fdsetRecv);
            hSocketMax = max(hSocketMax, hListenSocket);
            have_fds = true;
        }
        {
            LOCK(cs_vNodes);
            BOOST_FOREACH(CNode* pnode, vNodes)
            {
                if (pnode->hSocket == INVALID_SOCKET)
                    continue;
                FD_SET(pnode->hSocket, &fdsetRecv);
                FD_SET(pnode->hSocket, &fdsetError);
                hSocketMax = max(hSocketMax, pnode->hSocket);
                have_fds = true;
                {
                    TRY_LOCK(pnode->cs_vSend, lockSend);
                    if (lockSend && !pnode->vSend.empty())
                        FD_SET(pnode->hSocket, &fdsetSend);
                }
            }
        }

        vnThreadsRunning[THREAD_SOCKETHANDLER]--;
        int nSelect = select(have_fds ? hSocketMax + 1 : 0,
                             &fdsetRecv, &fdsetSend, &fdsetError, &timeout);
        vnThreadsRunning[THREAD_SOCKETHANDLER]++;
        if (fShutdown)
            return;
        if (nSelect == SOCKET_ERROR)
        {
            if (have_fds)
            {
                int nErr = WSAGetLastError();
                printf("socket select error %d\n", nErr);
                for (unsigned int i = 0; i <= hSocketMax; i++)
                    FD_SET(i, &fdsetRecv);
            }
            FD_ZERO(&fdsetSend);
            FD_ZERO(&fdsetError);
            Sleep(timeout.tv_usec/1000);
        }


        //
        // Accept new connections
        //
        BOOST_FOREACH(SOCKET hListenSocket, vhListenSocket)
        if (hListenSocket != INVALID_SOCKET && FD_ISSET(hListenSocket, &fdsetRecv))
        {
#ifdef USE_IPV6
            struct sockaddr_storage sockaddr;
#else
            struct sockaddr sockaddr;
#endif
            socklen_t len = sizeof(sockaddr);
            SOCKET hSocket = accept(hListenSocket, (struct sockaddr*)&sockaddr, &len);
            CAddress addr;
            int nInbound = 0;

            if (hSocket != INVALID_SOCKET)
                if (!addr.SetSockAddr((const struct sockaddr*)&sockaddr))
                    printf("Warning: Unknown socket family\n");

            {
                LOCK(cs_vNodes);
                BOOST_FOREACH(CNode* pnode, vNodes)
                    if (pnode->fInbound)
                        nInbound++;
            }

            if (hSocket == INVALID_SOCKET)
            {
                int nErr = WSAGetLastError();
                if (nErr != WSAEWOULDBLOCK)
                    printf("socket error accept failed: %d\n", nErr);
            }
            else if (nInbound >= GetArgInt("-maxconnections", 125) - MAX_OUTBOUND_CONNECTIONS)
            {
                {
                    LOCK(cs_setservAddNodeAddresses);
                    if (!setservAddNodeAddresses.count(addr))
                        CloseSocket(hSocket);
                }
            }
            else if (CNode::IsBanned(addr))
            {
                printf("connection from %s dropped (banned)\n", addr.ToString().c_str());
                CloseSocket(hSocket);
            }
            else
            {
                printf("accepted connection %s\n", addr.ToString().c_str());
                CNode* pnode = new CNode(hSocket, addr, "", true);
                pnode->AddRef();
                {
                    LOCK(cs_vNodes);
                    vNodes.push_back(pnode);
                }
            }
        }


        //
        // Service each socket
        //
        vector<CNode*> vNodesCopy;
        {
            LOCK(cs_vNodes);
            vNodesCopy = vNodes;
            BOOST_FOREACH(CNode* pnode, vNodesCopy)
                pnode->AddRef();
        }
        BOOST_FOREACH(CNode* pnode, vNodesCopy)
        {
            if (fShutdown)
                return;

            //
            // Receive
            //
            if (pnode->hSocket == INVALID_SOCKET)
                continue;
            if (FD_ISSET(pnode->hSocket, &fdsetRecv) || FD_ISSET(pnode->hSocket, &fdsetError))
            {
                TRY_LOCK(pnode->cs_vRecv, lockRecv);
                if (lockRecv)
                {
                    CDataStream& vRecv = pnode->vRecv;
                    uint64_t nPos = vRecv.size();

                    if (nPos > ReceiveBufferSize()) {
                        if (!pnode->fDisconnect)
                            printf("socket recv flood control disconnect (%" PRIszu " bytes)\n", vRecv.size());
                        pnode->CloseSocketDisconnect();
                    }
                    else {
                        // typical socket buffer is 8K-64K
                        char pchBuf[0x10000];
                        int nBytes = recv(pnode->hSocket, pchBuf, sizeof(pchBuf), MSG_DONTWAIT);
                        if (nBytes > 0)
                        {
                            vRecv.resize(nPos + nBytes);
                            memcpy(&vRecv[nPos], pchBuf, nBytes);
                            pnode->nLastRecv = GetTime();
                            pnode->nRecvBytes += nBytes;
                            pnode->RecordBytesRecv(nBytes);
                        }
                        else if (nBytes == 0)
                        {
                            // socket closed gracefully
                            if (!pnode->fDisconnect)
                                printf("socket closed\n");
                            pnode->CloseSocketDisconnect();
                        }
                        else if (nBytes < 0)
                        {
                            // error
                            int nErr = WSAGetLastError();
                            if (nErr != WSAEWOULDBLOCK && nErr != WSAEMSGSIZE && nErr != WSAEINTR && nErr != WSAEINPROGRESS)
                            {
                                if (!pnode->fDisconnect)
                                    printf("socket recv error %d\n", nErr);
                                pnode->CloseSocketDisconnect();
                            }
                        }
                    }
                }
            }

            //
            // Send
            //
            if (pnode->hSocket == INVALID_SOCKET)
                continue;
            if (FD_ISSET(pnode->hSocket, &fdsetSend))
            {
                TRY_LOCK(pnode->cs_vSend, lockSend);
                if (lockSend)
                {
                    CDataStream& vSend = pnode->vSend;
                    if (!vSend.empty())
                    {
                        int nBytes = send(pnode->hSocket, &vSend[0], vSend.size(), MSG_NOSIGNAL | MSG_DONTWAIT);
                        if (nBytes > 0)
                        {
                            vSend.erase(vSend.begin(), vSend.begin() + nBytes);
                            pnode->nLastSend = GetTime();
                            pnode->nSendBytes += nBytes;
                            pnode->RecordBytesSent(nBytes);
                        }
                        else if (nBytes < 0)
                        {
                            // error
                            int nErr = WSAGetLastError();
                            if (nErr != WSAEWOULDBLOCK && nErr != WSAEMSGSIZE && nErr != WSAEINTR && nErr != WSAEINPROGRESS)
                            {
                                printf("socket send error %d\n", nErr);
                                pnode->CloseSocketDisconnect();
                            }
                        }
                    }
                }
            }

            //
            // Inactivity checking
            //
            if (pnode->vSend.empty())
                pnode->nLastSendEmpty = GetTime();
            if (GetTime() - pnode->nTimeConnected > 60)
            {
                if (pnode->nLastRecv == 0 || pnode->nLastSend == 0)
                {
                    printf("socket no message in first 60 seconds, %d %d\n", pnode->nLastRecv != 0, pnode->nLastSend != 0);
                    pnode->fDisconnect = true;
                }
                else if (GetTime() - pnode->nLastSend > 90*60 && GetTime() - pnode->nLastSendEmpty > 90*60)
                {
                    printf("socket not sending\n");
                    pnode->fDisconnect = true;
                }
                else if (GetTime() - pnode->nLastRecv > 90*60)
                {
                    printf("socket inactivity timeout\n");
                    pnode->fDisconnect = true;
                }
            }
        }
        {
            LOCK(cs_vNodes);
            for_each(vNodesCopy.begin(), vNodesCopy.end(), Release);
        }

        Sleep(10);
    }
}

// DNS seeds
// Each pair gives a source name and a seed name.
// The first name is used as information source for addrman.
// The second name should resolve to a list of seed addresses.
static const char *strDNSSeed[][2] = {
    {"novacoin.karelia.pro", "dnsseed.novacoin.karelia.pro"},
    {"novacoin.ru", "dnsseed.novacoin.ru"},
    {"novacoin.ru", "testseed.novacoin.ru"},
    {"novaco.in", "dnsseed.novaco.in"},
};

void ThreadDNSAddressSeed(void* parg)
{
    // Make this thread recognisable as the DNS seeding thread
    RenameThread("novacoin-dnsseed");

    try
    {
        vnThreadsRunning[THREAD_DNSSEED]++;
        ThreadDNSAddressSeed2(parg);
        vnThreadsRunning[THREAD_DNSSEED]--;
    }
    catch (std::exception& e) {
        vnThreadsRunning[THREAD_DNSSEED]--;
        PrintException(&e, "ThreadDNSAddressSeed()");
    } catch (...) {
        vnThreadsRunning[THREAD_DNSSEED]--;
        throw; // support pthread_cancel()
    }
    printf("ThreadDNSAddressSeed exited\n");
}

void ThreadDNSAddressSeed2(void* parg)
{
    printf("ThreadDNSAddressSeed started\n");
    int found = 0;

    if (!fTestNet)
    {
        printf("Loading addresses from DNS seeds (could take a while)\n");

        for (unsigned int seed_idx = 0; seed_idx < ARRAYLEN(strDNSSeed); seed_idx++) {
            if (HaveNameProxy()) {
                AddOneShot(strDNSSeed[seed_idx][1]);
            } else {
                vector<CNetAddr> vaddr;
                vector<CAddress> vAdd;
                if (LookupHost(strDNSSeed[seed_idx][1], vaddr))
                {
                    BOOST_FOREACH(CNetAddr& ip, vaddr)
                    {
                        CAddress addr = CAddress(CService(ip, GetDefaultPort()));
                        addr.nTime = GetTime() - 3*nOneDay - GetRand(4*nOneDay); // use a random age between 3 and 7 days old
                        vAdd.push_back(addr);
                        found++;
                    }
                }
                addrman.Add(vAdd, CNetAddr(strDNSSeed[seed_idx][0], true));
            }
        }
    }

    printf("%d addresses found from DNS seeds\n", found);
}












uint32_t pnSeed[] =
{
    0xa52bf0da, 0x30aa43d8, 0x614488d5, 0x517b6fd5, 0xd4bf62d4, 0xb7d638d4, 0xbc12bcd1, 0xa2501bc6,
    0xfde617c6, 0x3337b1c6, 0x1dcd71c3, 0x2c1544c1, 0xe05f6ac1, 0x852f63c0, 0x3e2363c0, 0x15f563c0,
    0x430d63c0, 0x50d6a9c0, 0xf0a679c0, 0xefdeedbf, 0x7aaee8bc, 0x3a3dbbbc, 0xef218abc, 0x0bef78bc,
    0x8baa3eb2, 0x2bf913b2, 0x24ed9fb2, 0xb42289b2, 0x718a09b0, 0xe9433eb0, 0x559425b0, 0xc97e1fb0,
    0x18e1d4b0, 0x8f6cc1b0, 0xac3838ae, 0x86c0ffad, 0x6b0272a7, 0xa463f8a2, 0x6f17f3a2, 0xb3d6f3a2,
    0x9cd8f997, 0xd513fb94, 0x39e64880, 0x3859dd6f, 0x0b08fe6d, 0xe601fe6d, 0xeb44a26d, 0xfe53186c,
    0x203c2e68, 0x1c542868, 0x0caa8368, 0xb8748368, 0xccca4762, 0xc637555f, 0x638a545f, 0x59b2205f,
    0x52568c5f, 0xba568c5f, 0x8a568c5f, 0x31b0f45e, 0x54a0f45e, 0x37d6f15e, 0xc520175e, 0x7620175e,
    0xc310175e, 0x8e33b45e, 0x7abb5f5d, 0xd3014c5d, 0xa1e1485d, 0x9947645d, 0xfab8ff5c, 0xa979e65b,
    0xa879e65b, 0x9f79e65b, 0x9fa3d25b, 0x112a925b, 0x7b92905b, 0x60647a5b, 0x1e389d5a, 0x851afa59,
    0x0185ef59, 0x26549b59, 0x1c9efe57, 0xc54c1256, 0x1ad51955, 0x19d21955, 0x73c41955, 0x3f74ee55,
    0x633eea55, 0x6883d655, 0xfb72c655, 0x5360a653, 0x17c1ea52, 0xc661c852, 0x1ecdc852, 0x006a9752,
    0xf72d9252, 0x82650551, 0x36f1c851, 0x33f1c851, 0xd5c1864f, 0xb6bf1b4e, 0x96da184e, 0x40d0234d,
    0x9a96ab4c, 0x8fc2a84c, 0xb5dbd048, 0xf4644447, 0x2d51af47, 0xa9625445, 0x83f05243, 0x89672941,
    0x3a8bad3e, 0xf0a05436, 0x6ab7c936, 0x49971d32, 0xadd4482e, 0xcffd212e, 0x6730bc2e, 0x839aa12e,
    0x68d9692e, 0xc7183b25, 0x6c47bb25, 0x2490bb25, 0xad651c1f, 0x048a861f, 0x6937811f, 0x064b2d05,
    0x4d226805,
};

const char* pchTorSeed[] = 
{
    "seedp4knqnoei57u.onion",
    "seedr3hhlepyi7fd.onion",
    "seed3uuomkclbiz4.onion",
    "seedeh7qck3ouff5.onion",
    "5rg3vq4jagckeckf.onion",
    "seedt3sraf53ajiy.onion",
    "seedg4qyccsg42oq.onion",
    "novaqrtoywpg7jly.onion",
    "seed3d5wolqbgrcb.onion",
    "seed24u5dwph3qw4.onion",
    "mj26ulzbs2oskgym.onion",
    "eqon4usunavt76m7.onion",
    "seedd3aldwpslzl3.onion"
};

void DumpAddresses()
{
    int64_t nStart = GetTimeMillis();

    CAddrDB adb;
    adb.Write(addrman);

    printf("Flushed %d addresses to peers.dat  %" PRId64 "ms\n",
           addrman.size(), GetTimeMillis() - nStart);
}

void ThreadDumpAddress2(void* parg)
{
    printf("ThreadDumpAddress started\n");

    vnThreadsRunning[THREAD_DUMPADDRESS]++;
    while (!fShutdown)
    {
        DumpAddresses();
        vnThreadsRunning[THREAD_DUMPADDRESS]--;
        Sleep(600000);
        vnThreadsRunning[THREAD_DUMPADDRESS]++;
    }
    vnThreadsRunning[THREAD_DUMPADDRESS]--;
}

void ThreadDumpAddress(void* parg)
{
    // Make this thread recognisable as the address dumping thread
    RenameThread("novacoin-adrdump");

    try
    {
        ThreadDumpAddress2(parg);
    }
    catch (std::exception& e) {
        PrintException(&e, "ThreadDumpAddress()");
    }
    printf("ThreadDumpAddress exited\n");
}

void ThreadOpenConnections(void* parg)
{
    // Make this thread recognisable as the connection opening thread
    RenameThread("novacoin-opencon");

    try
    {
        vnThreadsRunning[THREAD_OPENCONNECTIONS]++;
        ThreadOpenConnections2(parg);
        vnThreadsRunning[THREAD_OPENCONNECTIONS]--;
    }
    catch (std::exception& e) {
        vnThreadsRunning[THREAD_OPENCONNECTIONS]--;
        PrintException(&e, "ThreadOpenConnections()");
    } catch (...) {
        vnThreadsRunning[THREAD_OPENCONNECTIONS]--;
        PrintException(NULL, "ThreadOpenConnections()");
    }
    printf("ThreadOpenConnections exited\n");
}

void static ProcessOneShot()
{
    string strDest;
    {
        LOCK(cs_vOneShots);
        if (vOneShots.empty())
            return;
        strDest = vOneShots.front();
        vOneShots.pop_front();
    }
    CAddress addr;
    CSemaphoreGrant grant(*semOutbound, true);
    if (grant) {
        if (!OpenNetworkConnection(addr, &grant, strDest.c_str(), true))
            AddOneShot(strDest);
    }
}

void ThreadOpenConnections2(void* parg)
{
    printf("ThreadOpenConnections started\n");

    // Connect to specific addresses
    if (mapArgs.count("-connect") && mapMultiArgs["-connect"].size() > 0)
    {
        for (int64_t nLoop = 0;; nLoop++)
        {
            ProcessOneShot();
            BOOST_FOREACH(string strAddr, mapMultiArgs["-connect"])
            {
                CAddress addr;
                OpenNetworkConnection(addr, NULL, strAddr.c_str());
                for (int i = 0; i < 10 && i < nLoop; i++)
                {
                    Sleep(500);
                    if (fShutdown)
                        return;
                }
            }
            Sleep(500);
        }
    }

    // Initiate network connections
    int64_t nStart = GetTime();
    for ( ; ; )
    {
        ProcessOneShot();

        vnThreadsRunning[THREAD_OPENCONNECTIONS]--;
        Sleep(500);
        vnThreadsRunning[THREAD_OPENCONNECTIONS]++;
        if (fShutdown)
            return;


        vnThreadsRunning[THREAD_OPENCONNECTIONS]--;
        CSemaphoreGrant grant(*semOutbound);
        vnThreadsRunning[THREAD_OPENCONNECTIONS]++;
        if (fShutdown)
            return;

        // Add seed nodes if IRC isn't working
        if (!IsLimited(NET_IPV4) && addrman.size()==0 && (GetTime() - nStart > 60) && !fTestNet)
        {
            std::vector<CAddress> vAdd;
            for (unsigned int i = 0; i < ARRAYLEN(pnSeed); i++)
            {
                // It'll only connect to one or two seed nodes because once it connects,
                // it'll get a pile of addresses with newer timestamps.
                // Seed nodes are given a random 'last seen time' of between one and two
                // weeks ago.
                struct in_addr ip;
                memcpy(&ip, &pnSeed[i], sizeof(ip));
                CAddress addr(CService(ip, GetDefaultPort()));
                addr.nTime = GetTime()-GetRand(nOneWeek)-nOneWeek;
                vAdd.push_back(addr);
            }
            addrman.Add(vAdd, CNetAddr("127.0.0.1"));
        }

        // Add Tor nodes if we have connection with onion router
        if (mapArgs.count("-tor"))
        {
            std::vector<CAddress> vAdd;
            for (unsigned int i = 0; i < ARRAYLEN(pchTorSeed); i++)
            {
                CAddress addr(CService(pchTorSeed[i], GetDefaultPort()));
                addr.nTime = GetTime()-GetRand(nOneWeek)-nOneWeek;
                vAdd.push_back(addr);
            }
            addrman.Add(vAdd, CNetAddr("dummyaddress.onion"));
        }

        //
        // Choose an address to connect to based on most recently seen
        //
        CAddress addrConnect;

        // Only connect out to one peer per network group (/16 for IPv4).
        // Do this here so we don't have to critsect vNodes inside mapAddresses critsect.
        int nOutbound = 0;
        set<vector<unsigned char> > setConnected;
        {
            LOCK(cs_vNodes);
            BOOST_FOREACH(CNode* pnode, vNodes) {
                if (!pnode->fInbound) {
                    setConnected.insert(pnode->addr.GetGroup());
                    nOutbound++;
                }
            }
        }

        int64_t nANow = GetAdjustedTime();

        int nTries = 0;
        for ( ; ; )
        {
            // use an nUnkBias between 10 (no outgoing connections) and 90 (8 outgoing connections)
            CAddress addr = addrman.Select(10 + min(nOutbound,8)*10);

            // if we selected an invalid address, restart
            if (!addr.IsValid() || setConnected.count(addr.GetGroup()) || IsLocal(addr))
                break;

            // If we didn't find an appropriate destination after trying 100 addresses fetched from addrman,
            // stop this loop, and let the outer loop run again (which sleeps, adds seed nodes, recalculates
            // already-connected network ranges, ...) before trying new addrman addresses.
            nTries++;
            if (nTries > 100)
                break;

            if (IsLimited(addr))
                continue;

            // only consider very recently tried nodes after 30 failed attempts
            if (nANow - addr.nLastTry < 600 && nTries < 30)
                continue;

            // do not allow non-default ports, unless after 50 invalid addresses selected already
            if (addr.GetPort() != GetDefaultPort() && nTries < 50)
                continue;

            addrConnect = addr;
            break;
        }

        if (addrConnect.IsValid())
            OpenNetworkConnection(addrConnect, &grant);
    }
}

void ThreadOpenAddedConnections(void* parg)
{
    // Make this thread recognisable as the connection opening thread
    RenameThread("novacoin-opencon");

    try
    {
        vnThreadsRunning[THREAD_ADDEDCONNECTIONS]++;
        ThreadOpenAddedConnections2(parg);
        vnThreadsRunning[THREAD_ADDEDCONNECTIONS]--;
    }
    catch (std::exception& e) {
        vnThreadsRunning[THREAD_ADDEDCONNECTIONS]--;
        PrintException(&e, "ThreadOpenAddedConnections()");
    } catch (...) {
        vnThreadsRunning[THREAD_ADDEDCONNECTIONS]--;
        PrintException(NULL, "ThreadOpenAddedConnections()");
    }
    printf("ThreadOpenAddedConnections exited\n");
}

void ThreadOpenAddedConnections2(void* parg)
{
    printf("ThreadOpenAddedConnections started\n");

    {
        LOCK(cs_vAddedNodes);
        vAddedNodes = mapMultiArgs["-addnode"];
    }

    if (HaveNameProxy()) {
        while(!fShutdown) {
            list<string> lAddresses(0);
            {
                LOCK(cs_vAddedNodes);
                BOOST_FOREACH(string& strAddNode, vAddedNodes)
                    lAddresses.push_back(strAddNode);
            }
            BOOST_FOREACH(string& strAddNode, lAddresses) {
                CAddress addr;
                CSemaphoreGrant grant(*semOutbound);
                OpenNetworkConnection(addr, &grant, strAddNode.c_str());
                Sleep(500);
            }
            vnThreadsRunning[THREAD_ADDEDCONNECTIONS]--;
            Sleep(120000); // Retry every 2 minutes
            vnThreadsRunning[THREAD_ADDEDCONNECTIONS]++;
        }
        return;
    }

    for (uint32_t i = 0; true; i++)
    {
        list<string> lAddresses(0);
        {
            LOCK(cs_vAddedNodes);
            BOOST_FOREACH(string& strAddNode, vAddedNodes)
                lAddresses.push_back(strAddNode);
        }

        list<vector<CService> > lservAddressesToAdd(0);
        BOOST_FOREACH(string& strAddNode, lAddresses)
        {
            vector<CService> vservNode(0);
            if (Lookup(strAddNode.c_str(), vservNode, GetDefaultPort(), fNameLookup, 0))
            {
                lservAddressesToAdd.push_back(vservNode);
                {
                    LOCK(cs_setservAddNodeAddresses);
                    BOOST_FOREACH(CService& serv, vservNode)
                        setservAddNodeAddresses.insert(serv);
                }
            }
        }
        // Attempt to connect to each IP for each addnode entry until at least one is successful per addnode entry
        // (keeping in mind that addnode entries can have many IPs if fNameLookup)
        {
            LOCK(cs_vNodes);
            BOOST_FOREACH(CNode* pnode, vNodes)
                for (list<vector<CService> >::iterator it = lservAddressesToAdd.begin(); it != lservAddressesToAdd.end(); it++)
                {
                    BOOST_FOREACH(CService& addrNode, *(it))
                        if (pnode->addr == addrNode)
                        {
                            it = lservAddressesToAdd.erase(it);
                            if(it != lservAddressesToAdd.begin())
                                it--;
                            break;
                        }
                    if (it == lservAddressesToAdd.end())
                        break;
                }
        }
        BOOST_FOREACH(vector<CService>& vserv, lservAddressesToAdd)
        {
            if (vserv.size() == 0)
                continue;
            CSemaphoreGrant grant(*semOutbound);
            OpenNetworkConnection(CAddress(vserv[i % vserv.size()]), &grant);
            Sleep(500);
            if (fShutdown)
                return;
        }
        if (fShutdown)
            return;
        vnThreadsRunning[THREAD_ADDEDCONNECTIONS]--;
        Sleep(120000); // Retry every 2 minutes
        vnThreadsRunning[THREAD_ADDEDCONNECTIONS]++;
        if (fShutdown)
            return;
    }
}

// if successful, this moves the passed grant to the constructed node
bool OpenNetworkConnection(const CAddress& addrConnect, CSemaphoreGrant *grantOutbound, const char *strDest, bool fOneShot)
{
    //
    // Initiate outbound network connection
    //
    if (fShutdown)
        return false;
    if (!strDest)
        if (IsLocal(addrConnect) ||
            FindNode((CNetAddr)addrConnect) || CNode::IsBanned(addrConnect) ||
            FindNode(addrConnect.ToStringIPPort().c_str()))
            return false;
    if (strDest && FindNode(strDest))
        return false;

    vnThreadsRunning[THREAD_OPENCONNECTIONS]--;
    CNode* pnode = ConnectNode(addrConnect, strDest);
    vnThreadsRunning[THREAD_OPENCONNECTIONS]++;
    if (fShutdown)
        return false;
    if (!pnode)
        return false;
    if (grantOutbound)
        grantOutbound->MoveTo(pnode->grantOutbound);
    pnode->fNetworkNode = true;
    if (fOneShot)
        pnode->fOneShot = true;

    return true;
}

// for now, use a very simple selection metric: the node from which we received
// most recently
static int64_t NodeSyncScore(const CNode *pnode) {
    return pnode->nLastRecv;
}

void static StartSync(const vector<CNode*> &vNodes) {
    CNode *pnodeNewSync = NULL;
    int64_t nBestScore = 0;

    // Iterate over all nodes
    BOOST_FOREACH(CNode* pnode, vNodes) {
        // check preconditions for allowing a sync
        if (!pnode->fClient && !pnode->fOneShot &&
            !pnode->fDisconnect && pnode->fSuccessfullyConnected &&
            (pnode->nStartingHeight > (nBestHeight - 144)) &&
            (pnode->nVersion < NOBLKS_VERSION_START || pnode->nVersion >= NOBLKS_VERSION_END)) {
            // if ok, compare node's score with the best so far
            int64_t nScore = NodeSyncScore(pnode);
            if (pnodeNewSync == NULL || nScore > nBestScore) {
                pnodeNewSync = pnode;
                nBestScore = nScore;
            }
        }
    }
    // if a new sync candidate was found, start sync!
    if (pnodeNewSync) {
        pnodeNewSync->fStartSync = true;
        pnodeSync = pnodeNewSync;
    }
}

void ThreadMessageHandler(void* parg)
{
    // Make this thread recognisable as the message handling thread
    RenameThread("novacoin-msghand");

    try
    {
        vnThreadsRunning[THREAD_MESSAGEHANDLER]++;
        ThreadMessageHandler2(parg);
        vnThreadsRunning[THREAD_MESSAGEHANDLER]--;
    }
    catch (std::exception& e) {
        vnThreadsRunning[THREAD_MESSAGEHANDLER]--;
        PrintException(&e, "ThreadMessageHandler()");
    } catch (...) {
        vnThreadsRunning[THREAD_MESSAGEHANDLER]--;
        PrintException(NULL, "ThreadMessageHandler()");
    }
    printf("ThreadMessageHandler exited\n");
}

void ThreadMessageHandler2(void* parg)
{
    printf("ThreadMessageHandler started\n");
    SetThreadPriority(THREAD_PRIORITY_BELOW_NORMAL);
    while (!fShutdown)
    {
        bool fHaveSyncNode = false;
        vector<CNode*> vNodesCopy;
        {
            LOCK(cs_vNodes);
            vNodesCopy = vNodes;
            BOOST_FOREACH(CNode* pnode, vNodesCopy) {
                pnode->AddRef();
                if (pnode == pnodeSync)
                    fHaveSyncNode = true;
            }
        }

        if (!fHaveSyncNode)
            StartSync(vNodesCopy);

        // Poll the connected nodes for messages
        CNode* pnodeTrickle = NULL;
        if (!vNodesCopy.empty())
            pnodeTrickle = vNodesCopy[GetRand(vNodesCopy.size())];
        BOOST_FOREACH(CNode* pnode, vNodesCopy)
        {
            // Receive messages
            {
                TRY_LOCK(pnode->cs_vRecv, lockRecv);
                if (lockRecv)
                    ProcessMessages(pnode);
            }
            if (fShutdown)
                return;

            // Send messages
            {
                TRY_LOCK(pnode->cs_vSend, lockSend);
                if (lockSend)
                    SendMessages(pnode, pnode == pnodeTrickle);
            }
            if (fShutdown)
                return;
        }

        {
            LOCK(cs_vNodes);
            for_each(vNodesCopy.begin(), vNodesCopy.end(), Release);
        }

        // Wait and allow messages to bunch up.
        // Reduce vnThreadsRunning so StopNode has permission to exit while
        // we're sleeping, but we must always check fShutdown after doing this.
        vnThreadsRunning[THREAD_MESSAGEHANDLER]--;
        Sleep(100);
        if (fRequestShutdown)
            StartShutdown();
        vnThreadsRunning[THREAD_MESSAGEHANDLER]++;
        if (fShutdown)
            return;
    }
}






bool BindListenPort(const CService &addrBind, string& strError)
{
    strError = "";
    int nOne = 1;

    // Create socket for listening for incoming connections
#ifdef USE_IPV6
    struct sockaddr_storage sockaddr;
#else
    struct sockaddr sockaddr;
#endif
    socklen_t len = sizeof(sockaddr);
    if (!addrBind.GetSockAddr((struct sockaddr*)&sockaddr, &len))
    {
        strError = strprintf("Error: bind address family for %s not supported", addrBind.ToString().c_str());
        printf("%s\n", strError.c_str());
        return false;
    }

    SOCKET hListenSocket = socket(((struct sockaddr*)&sockaddr)->sa_family, SOCK_STREAM, IPPROTO_TCP);
    if (hListenSocket == INVALID_SOCKET)
    {
        strError = strprintf("Error: Couldn't open socket for incoming connections (socket returned error %d)", WSAGetLastError());
        printf("%s\n", strError.c_str());
        return false;
    }

#ifndef WIN32
#ifdef SO_NOSIGPIPE
    // Different way of disabling SIGPIPE on BSD
    setsockopt(hListenSocket, SOL_SOCKET, SO_NOSIGPIPE, (void*)&nOne, sizeof(int));
#endif
    // Allow binding if the port is still in TIME_WAIT state after
    // the program was closed and restarted. Not an issue on windows!
    setsockopt(hListenSocket, SOL_SOCKET, SO_REUSEADDR, (void*)&nOne, sizeof(int));
#endif

#ifdef WIN32
    // Set to non-blocking, incoming connections will also inherit this
    if (ioctlsocket(hListenSocket, FIONBIO, (u_long*)&nOne) == SOCKET_ERROR)
#else
    if (fcntl(hListenSocket, F_SETFL, O_NONBLOCK) == SOCKET_ERROR)
#endif
    {
        strError = strprintf("Error: Couldn't set properties on socket for incoming connections (error %d)", WSAGetLastError());
        printf("%s\n", strError.c_str());
        return false;
    }

#ifdef USE_IPV6
    // some systems don't have IPV6_V6ONLY but are always v6only; others do have the option
    // and enable it by default or not. Try to enable it, if possible.
    if (addrBind.IsIPv6()) {
#ifdef IPV6_V6ONLY
#ifdef WIN32
        setsockopt(hListenSocket, IPPROTO_IPV6, IPV6_V6ONLY, (const char*)&nOne, sizeof(int));
#else
        setsockopt(hListenSocket, IPPROTO_IPV6, IPV6_V6ONLY, (void*)&nOne, sizeof(int));
#endif
#endif
#ifdef WIN32
        int nProtLevel = PROTECTION_LEVEL_UNRESTRICTED;
        setsockopt(hListenSocket, IPPROTO_IPV6, IPV6_PROTECTION_LEVEL, (const char*)&nProtLevel, sizeof(int));
#endif
    }
#endif

    if (::bind(hListenSocket, (struct sockaddr*)&sockaddr, len) == SOCKET_ERROR)
    {
        int nErr = WSAGetLastError();
        if (nErr == WSAEADDRINUSE)
            strError = strprintf(_("Unable to bind to %s on this computer. NovaCoin is probably already running."), addrBind.ToString().c_str());
        else
            strError = strprintf(_("Unable to bind to %s on this computer (bind returned error %d, %s)"), addrBind.ToString().c_str(), nErr, strerror(nErr));
        printf("%s\n", strError.c_str());
        CloseSocket(hListenSocket);
        return false;
    }
    printf("Bound to %s\n", addrBind.ToString().c_str());

    // Listen for incoming connections
    if (listen(hListenSocket, SOMAXCONN) == SOCKET_ERROR)
    {
        strError = strprintf("Error: Listening for incoming connections failed (listen returned error %d)", WSAGetLastError());
        printf("%s\n", strError.c_str());
        CloseSocket(hListenSocket);
        return false;
    }

    vhListenSocket.push_back(hListenSocket);

    if (addrBind.IsRoutable() && fDiscover)
        AddLocal(addrBind, LOCAL_BIND);

    return true;
}

void static Discover()
{
    if (!fDiscover)
        return;

#ifdef WIN32
    // Get local host IP
    char pszHostName[1000] = "";
    if (gethostname(pszHostName, sizeof(pszHostName)) != SOCKET_ERROR)
    {
        vector<CNetAddr> vaddr;
        if (LookupHost(pszHostName, vaddr))
        {
            BOOST_FOREACH (const CNetAddr &addr, vaddr)
            {
                AddLocal(addr, LOCAL_IF);
            }
        }
    }
#else
    // Get local host ip
    struct ifaddrs* myaddrs;
    if (getifaddrs(&myaddrs) == 0)
    {
        for (struct ifaddrs* ifa = myaddrs; ifa != NULL; ifa = ifa->ifa_next)
        {
            if (ifa->ifa_addr == NULL) continue;
            if ((ifa->ifa_flags & IFF_UP) == 0) continue;
            if (strcmp(ifa->ifa_name, "lo") == 0) continue;
            if (strcmp(ifa->ifa_name, "lo0") == 0) continue;
            if (ifa->ifa_addr->sa_family == AF_INET)
            {
                struct sockaddr_in* s4 = (struct sockaddr_in*)(ifa->ifa_addr);
                CNetAddr addr(s4->sin_addr);
                if (AddLocal(addr, LOCAL_IF))
                    printf("IPv4 %s: %s\n", ifa->ifa_name, addr.ToString().c_str());
            }
#ifdef USE_IPV6
            else if (ifa->ifa_addr->sa_family == AF_INET6)
            {
                struct sockaddr_in6* s6 = (struct sockaddr_in6*)(ifa->ifa_addr);
                CNetAddr addr(s6->sin6_addr);
                if (AddLocal(addr, LOCAL_IF))
                    printf("IPv6 %s: %s\n", ifa->ifa_name, addr.ToString().c_str());
            }
#endif
        }
        freeifaddrs(myaddrs);
    }
#endif

    // Don't use external IPv4 discovery, when -onlynet="IPv6"
    if (!IsLimited(NET_IPV4))
        NewThread(ThreadGetMyExternalIP, NULL);
}

void StartNode(void* parg)
{
    // Make this thread recognisable as the startup thread
    RenameThread("novacoin-start");

    if (semOutbound == NULL) {
        // initialize semaphore
        int nMaxOutbound = min(MAX_OUTBOUND_CONNECTIONS, GetArgInt("-maxconnections", 125));
        semOutbound = new CSemaphore(nMaxOutbound);
    }

    if (pnodeLocalHost == NULL)
        pnodeLocalHost = new CNode(INVALID_SOCKET, CAddress(CService("127.0.0.1", nPortZero), nLocalServices));

    Discover();

    //
    // Start threads
    //

    if (!GetBoolArg("-dnsseed", true))
        printf("DNS seeding disabled\n");
    else
        if (!NewThread(ThreadDNSAddressSeed, NULL))
            printf("Error: NewThread(ThreadDNSAddressSeed) failed\n");

    // Get addresses from IRC and advertise ours
    if (!GetBoolArg("-irc", true))
        printf("IRC seeding disabled\n");
    else
        if (!NewThread(ThreadIRCSeed, NULL))
            printf("Error: NewThread(ThreadIRCSeed) failed\n");

    // Send and receive from sockets, accept connections
    if (!NewThread(ThreadSocketHandler, NULL))
        printf("Error: NewThread(ThreadSocketHandler) failed\n");

    // Initiate outbound connections from -addnode
    if (!NewThread(ThreadOpenAddedConnections, NULL))
        printf("Error: NewThread(ThreadOpenAddedConnections) failed\n");

    // Initiate outbound connections
    if (!NewThread(ThreadOpenConnections, NULL))
        printf("Error: NewThread(ThreadOpenConnections) failed\n");

    // Process messages
    if (!NewThread(ThreadMessageHandler, NULL))
        printf("Error: NewThread(ThreadMessageHandler) failed\n");

    // Dump network addresses
    if (!NewThread(ThreadDumpAddress, NULL))
        printf("Error; NewThread(ThreadDumpAddress) failed\n");

    // Mine proof-of-stake blocks in the background
    if (!NewThread(ThreadStakeMiner, pwalletMain))
        printf("Error: NewThread(ThreadStakeMiner) failed\n");

    // Trusted NTP server, it's localhost by default.
    strTrustedUpstream = GetArg("-ntp", "localhost");

    // Start periodical NTP sampling thread
    NewThread(ThreadNtpSamples, NULL);

}

bool StopNode()
{
    printf("StopNode()\n");
    fShutdown = true;
    nTransactionsUpdated++;
    int64_t nStart = GetTime();
    {
        LOCK(cs_main);
        ThreadScriptCheckQuit();
    }
    if (semOutbound)
        for (int i=0; i<MAX_OUTBOUND_CONNECTIONS; i++)
            semOutbound->post();
    for ( ; ; )
    {
        int nThreadsRunning = 0;
        for (int n = 0; n < THREAD_MAX; n++)
            nThreadsRunning += vnThreadsRunning[n];
        if (nThreadsRunning == 0)
            break;
        if (GetTime() - nStart > 20)
            break;
        Sleep(20);
    };
    if (vnThreadsRunning[THREAD_SOCKETHANDLER] > 0) printf("ThreadSocketHandler still running\n");
    if (vnThreadsRunning[THREAD_OPENCONNECTIONS] > 0) printf("ThreadOpenConnections still running\n");
    if (vnThreadsRunning[THREAD_MESSAGEHANDLER] > 0) printf("ThreadMessageHandler still running\n");
    if (vnThreadsRunning[THREAD_RPCLISTENER] > 0) printf("ThreadRPCListener still running\n");
    if (vnThreadsRunning[THREAD_RPCHANDLER] > 0) printf("ThreadsRPCServer still running\n");
    if (vnThreadsRunning[THREAD_DNSSEED] > 0) printf("ThreadDNSAddressSeed still running\n");
    if (vnThreadsRunning[THREAD_ADDEDCONNECTIONS] > 0) printf("ThreadOpenAddedConnections still running\n");
    if (vnThreadsRunning[THREAD_DUMPADDRESS] > 0) printf("ThreadDumpAddresses still running\n");
    if (vnThreadsRunning[THREAD_MINTER] > 0) printf("ThreadStakeMinter still running\n");
    if (vnThreadsRunning[THREAD_SCRIPTCHECK] > 0) printf("ThreadScriptCheck still running\n");
    while (vnThreadsRunning[THREAD_MESSAGEHANDLER] > 0 || vnThreadsRunning[THREAD_RPCHANDLER] > 0 || vnThreadsRunning[THREAD_SCRIPTCHECK] > 0)
        Sleep(20);
    Sleep(50);
    DumpAddresses();

    return true;
}

class CNetCleanup
{
public:
    CNetCleanup()
    {
    }
    ~CNetCleanup()
    {
        // Close sockets
        BOOST_FOREACH(CNode* pnode, vNodes)
            if (pnode->hSocket != INVALID_SOCKET)
                CloseSocket(pnode->hSocket);
        BOOST_FOREACH(SOCKET hListenSocket, vhListenSocket)
            if (hListenSocket != INVALID_SOCKET)
                if (!CloseSocket(hListenSocket))
                    printf("CloseSocket(hListenSocket) failed with error %d\n", WSAGetLastError());

        // clean up some globals (to help leak detection)
        BOOST_FOREACH(CNode *pnode, vNodes)
            delete pnode;
        BOOST_FOREACH(CNode *pnode, vNodesDisconnected)
            delete pnode;
        vNodes.clear();
        vNodesDisconnected.clear();
        delete semOutbound;
        semOutbound = NULL;
        delete pnodeLocalHost;
        pnodeLocalHost = NULL;

#ifdef WIN32
        // Shutdown Windows Sockets
        WSACleanup();
#endif
    }
}
instance_of_cnetcleanup;

void RelayTransaction(const CTransaction& tx, const uint256& hash)
{
    CDataStream ss(SER_NETWORK, PROTOCOL_VERSION);
    ss.reserve(10000);
    ss << tx;
    RelayTransaction(tx, hash, ss);
}

void RelayTransaction(const CTransaction& tx, const uint256& hash, const CDataStream& ss)
{
    CInv inv(MSG_TX, hash);
    {
        LOCK(cs_mapRelay);
        // Expire old relay messages
        while (!vRelayExpiration.empty() && vRelayExpiration.front().first < GetTime())
        {
            mapRelay.erase(vRelayExpiration.front().second);
            vRelayExpiration.pop_front();
        }

        // Save original serialized message so newer versions are preserved
        mapRelay.insert(std::make_pair(inv, ss));
        vRelayExpiration.push_back(std::make_pair(GetTime() + 15 * 60, inv));
    }

    RelayInventory(inv);
}

void CNode::RecordBytesRecv(uint64_t bytes)
{
    LOCK(cs_totalBytesRecv);
    nTotalBytesRecv += bytes;
}

void CNode::RecordBytesSent(uint64_t bytes)
{
    LOCK(cs_totalBytesSent);
    nTotalBytesSent += bytes;
}

uint64_t CNode::GetTotalBytesRecv()
{
    LOCK(cs_totalBytesRecv);
    return nTotalBytesRecv;
}

uint64_t CNode::GetTotalBytesSent()
{
    LOCK(cs_totalBytesSent);
    return nTotalBytesSent;
}