Method ConnectNode

src/net.cpp:370–464

}

CNode* CConnman::ConnectNode(CAddress addrConnect, const char *pszDest, bool fCountFailure, bool manual_connection)
{
    if (pszDest == nullptr) {
        if (IsLocal(addrConnect))
            return nullptr;

        // Look for an existing connection
        CNode* pnode = FindNode(static_cast<CService>(addrConnect));
        if (pnode)
        {
            LogPrintf("Failed to open new connection, already connected\n");
            return nullptr;
        }
    }

    /// debug print
    LogPrint(BCLog::NET, "trying connection %s lastseen=%.1fhrs\n",
        pszDest ? pszDest : addrConnect.ToString(),
        pszDest ? 0.0 : (double)(GetAdjustedTime() - addrConnect.nTime)/3600.0);

    // Resolve
    const int default_port = Params().GetDefaultPort();
    if (pszDest) {
        std::vector<CService> resolved;
        if (Lookup(pszDest, resolved,  default_port, fNameLookup && !HaveNameProxy(), 256) && !resolved.empty()) {
            addrConnect = CAddress(resolved[GetRand(resolved.size())], NODE_NONE);
            if (!addrConnect.IsValid()) {
                LogPrint(BCLog::NET, "Resolver returned invalid address %s for %s\n", addrConnect.ToString(), pszDest);
                return nullptr;
            }
            // It is possible that we already have a connection to the IP/port pszDest resolved to.
            // In that case, drop the connection that was just created, and return the existing CNode instead.
            // Also store the name we used to connect in that CNode, so that future FindNode() calls to that
            // name catch this early.
            LOCK(cs_vNodes);
            CNode* pnode = FindNode(static_cast<CService>(addrConnect));
            if (pnode)
            {
                pnode->MaybeSetAddrName(std::string(pszDest));
                LogPrintf("Failed to open new connection, already connected\n");
                return nullptr;
            }
        }
    }

    // Connect
    bool connected = false;
    SOCKET hSocket = INVALID_SOCKET;
    proxyType proxy;
    if (addrConnect.IsValid()) {
        bool proxyConnectionFailed = false;

        if (GetProxy(addrConnect.GetNetwork(), proxy)) {
            hSocket = CreateSocket(proxy.proxy);
            if (hSocket == INVALID_SOCKET) {
                return nullptr;
            }
            connected = ConnectThroughProxy(proxy, addrConnect.ToStringIP(), addrConnect.GetPort(), hSocket, nConnectTimeout, &proxyConnectionFailed);