TransceiverSocket.cc

#include "otsdaq/NetworkUtilities/TransceiverSocket.h"
#include "otsdaq/Macros/CoutMacros.h"
#include "otsdaq/MessageFacility/MessageFacility.h"
 
#include <arpa/inet.h>
#include <unistd.h>
#include <chrono>
#include <cstring>
#include <iostream>
#include <limits>
#include <map>
#include <mutex>
#include <set>
#include <thread>
#include <vector>
 
using namespace ots;
 
//==============================================================================
TransceiverSocket::TransceiverSocket(void)
{
    __COUT__ << "TransceiverSocket constructor " << __E__;
}
 
//==============================================================================
TransceiverSocket::TransceiverSocket(std::string IPAddress, unsigned int port)
    : Socket(IPAddress, port)
{
    __COUT__ << "TransceiverSocket constructor " << IPAddress << ":" << port << __E__;
}
 
//==============================================================================
TransceiverSocket::~TransceiverSocket(void) {}
 
//==============================================================================
int TransceiverSocket::acknowledge(const std::string& buffer,
                                   bool               verbose /* = false */,
                                   size_t             maxChunkSize /* = 1500 */,
                                   unsigned int       interPacketGapUSeconds /* = 0 */,
                                   bool               enableRetransmission /* = false */)
{
    if(verbose)
        __COUTT__ << "Acknowledging on Socket Descriptor #: " << socketNumber_
                  << " from-port: " << ntohs(socketAddress_.sin_port)
                  << " to-port: " << ntohs(ReceiverSocket::fromAddress_.sin_port)
                  << " retransmission: " << (enableRetransmission ? "ON" : "OFF")
                  << std::endl;
 
    if(!enableRetransmission)
    {
        //====================================================================
        // Original non-retransmission mode (unchanged behavior)
        //====================================================================
        // lockout other senders for the remainder of this scope
        std::lock_guard<std::mutex> lock(sendMutex_);
 
        const size_t MAX_SEND_SIZE =
            maxChunkSize > 65500u ? static_cast<size_t>(65500u) : maxChunkSize;
        size_t offset      = 0;
        int    sendToSize  = 1;
        int    sizeInBytes = 1;
 
        while(offset < buffer.size() && sendToSize > 0)
        {
            auto thisSize = sizeInBytes * (buffer.size() - offset) > MAX_SEND_SIZE
                                ? MAX_SEND_SIZE
                                : sizeInBytes * (buffer.size() - offset);
            if(verbose)
                __COUTTV__(thisSize);
            sendToSize = sendto(socketNumber_,
                                &buffer[0] + offset,
                                thisSize,
                                0,
                                (struct sockaddr*)&(ReceiverSocket::fromAddress_),
                                sizeof(sockaddr_in));
            offset += sendToSize / sizeInBytes;
            if(interPacketGapUSeconds > 0 && offset < buffer.size() && sendToSize > 0)
                usleep(interPacketGapUSeconds);
        }
 
        if(sendToSize <= 0)
        {
            __SS__ << "Error writing buffer from port "
                   << ntohs(TransmitterSocket::socketAddress_.sin_port) << ": "
                   << strerror(errno) << std::endl;
            __SS_THROW__;
        }
        return 0;
    }
 
    //====================================================================
    // Retransmission mode: delegate entirely to sendAll() which handles
    // packet building, initial send, and retransmit request handling.
    //====================================================================
    return sendAll(buffer, verbose, maxChunkSize, interPacketGapUSeconds);
}  //end acknowledge()
 
//==============================================================================
int TransceiverSocket::sendAll(const std::string& buffer,
                               bool               verbose /* = false */,
                               size_t             maxChunkSize /* = 65500 */,
                               unsigned int       interPacketGapUSeconds /* = 0 */)
{
    if(verbose)
        __COUT__ << "sendAll: retransmission-mode send on Socket Descriptor #: "
                 << socketNumber_ << " from-port: " << ntohs(socketAddress_.sin_port)
                 << " to-port: " << ntohs(ReceiverSocket::fromAddress_.sin_port)
                 << " buffer size: " << buffer.size() << __E__;
 
    const size_t MAX_SEND_SIZE =
        maxChunkSize > 65500u ? static_cast<size_t>(65500u) : maxChunkSize;
 
    // The payload per packet is reduced by the header size
    const size_t payloadMax = MAX_SEND_SIZE > RETRANSMIT_HEADER_SIZE
                                  ? MAX_SEND_SIZE - RETRANSMIT_HEADER_SIZE
                                  : 1;
 
    // Calculate total number of packets. The on-wire header carries the count
    // as uint16_t, so reject buffers that would require more than 65535 packets.
    const size_t packetsNeeded = (buffer.size() + payloadMax - 1) / payloadMax;
    if(packetsNeeded > std::numeric_limits<uint16_t>::max())
    {
        __SS__ << "sendAll: buffer size " << buffer.size() << " requires "
               << packetsNeeded
               << " packets, which exceeds the uint16_t protocol limit of "
               << std::numeric_limits<uint16_t>::max() << " (payloadMax=" << payloadMax
               << ")." << std::endl;
        __SS_THROW__;
    }
    uint16_t totalPackets = static_cast<uint16_t>(packetsNeeded);
    if(totalPackets == 0)
        totalPackets = 1;  // send at least one packet even for empty buffer
 
    if(verbose)
        __COUT__ << "sendAll: sending " << totalPackets << " packets for "
                 << buffer.size() << " bytes, payloadMax=" << payloadMax << __E__;
 
    // Build and cache all packets (header + payload) for retransmit use
    std::vector<std::string> packets(totalPackets);
    {
        size_t offset = 0;
        for(uint16_t pi = 0; pi < totalPackets; ++pi)
        {
            size_t payloadSize = (buffer.size() - offset) > payloadMax
                                     ? payloadMax
                                     : (buffer.size() - offset);
 
            char     header[RETRANSMIT_HEADER_SIZE];
            uint16_t netMagic   = htons(RETRANSMIT_MAGIC);
            uint16_t netIndex   = htons(pi);
            uint16_t netTotal   = htons(totalPackets);
            uint16_t netPaySize = htons(static_cast<uint16_t>(payloadSize));
            std::memcpy(header + 0, &netMagic, 2);
            std::memcpy(header + 2, &netIndex, 2);
            std::memcpy(header + 4, &netTotal, 2);
            std::memcpy(header + 6, &netPaySize, 2);
 
            packets[pi].assign(header, RETRANSMIT_HEADER_SIZE);
            packets[pi].append(buffer, offset, payloadSize);
            offset += payloadSize;
        }
    }
 
    // Send all packets initially (lock sendMutex_ for the burst)
    {
        std::lock_guard<std::mutex> lock(sendMutex_);
        for(uint16_t pi = 0; pi < totalPackets; ++pi)
        {
            int sendToSize = sendto(socketNumber_,
                                    packets[pi].data(),
                                    packets[pi].size(),
                                    0,
                                    (struct sockaddr*)&(ReceiverSocket::fromAddress_),
                                    sizeof(sockaddr_in));
            if(sendToSize <= 0)
            {
                __SS__ << "sendAll: error writing packet " << pi << "/" << totalPackets
                       << " from port " << ntohs(socketAddress_.sin_port) << ": "
                       << strerror(errno) << std::endl;
                __SS_THROW__;
            }
            if(verbose)
                __COUTT__ << "sendAll: sent packet " << pi << "/" << totalPackets
                          << " size=" << packets[pi].size() << std::endl;
 
            if(interPacketGapUSeconds > 0 && pi + 1 < totalPackets)
                usleep(interPacketGapUSeconds);
        }
    }
 
    // Wait for retransmit requests from receiver.
    // Retransmit request format: magic(2 bytes) + list of uint16 missing indices
    // Done signal format:        magic(2 bytes) + 0xFFFF(2 bytes)
    const unsigned int retransmitTimeoutSeconds = 5;
    const unsigned int maxRetransmitRounds      = 20;
 
    for(unsigned int round = 0; round < maxRetransmitRounds; ++round)
    {
        std::string retransmitRequest;
        int         rc = receive(retransmitRequest,
                         retransmitTimeoutSeconds,
                         0 /*timeoutUSeconds*/,
                         false /*verbose*/);
        if(rc < 0)
        {
            // Timeout - assume receiver got everything (or gave up)
            if(verbose)
                __COUT__ << "sendAll: no retransmit request after "
                         << retransmitTimeoutSeconds
                         << "s timeout, assuming transfer complete." << __E__;
            break;
        }
 
        if(retransmitRequest.size() < 4)
            continue;
 
        uint16_t reqMagic;
        std::memcpy(&reqMagic, retransmitRequest.data(), 2);
        reqMagic = ntohs(reqMagic);
        if(reqMagic != RETRANSMIT_MAGIC)
            continue;
 
        // Check for "done" signal (magic + 0xFFFF)
        uint16_t firstVal;
        std::memcpy(&firstVal, retransmitRequest.data() + 2, 2);
        firstVal = ntohs(firstVal);
        if(firstVal == 0xFFFF)
        {
            if(verbose)
                __COUT__ << "sendAll: received 'all done' from receiver." << __E__;
            break;
        }
 
        // Parse list of missing packet indices and resend them
        size_t numIndices = (retransmitRequest.size() - 2) / 2;
        if(verbose)
            __COUT__ << "sendAll: retransmit request for " << numIndices
                     << " packets (round " << round << ")." << __E__;
 
        // Lock sendMutex_ for the resend burst
        std::lock_guard<std::mutex> lock(sendMutex_);
        for(size_t i = 0; i < numIndices; ++i)
        {
            uint16_t missingIdx;
            std::memcpy(&missingIdx, retransmitRequest.data() + 2 + i * 2, 2);
            missingIdx = ntohs(missingIdx);
 
            if(missingIdx < totalPackets)
            {
                int sendToSize = sendto(socketNumber_,
                                        packets[missingIdx].data(),
                                        packets[missingIdx].size(),
                                        0,
                                        (struct sockaddr*)&(ReceiverSocket::fromAddress_),
                                        sizeof(sockaddr_in));
                if(sendToSize <= 0)
                {
                    __SS__ << "sendAll: error resending packet " << missingIdx << ": "
                           << strerror(errno) << std::endl;
                    __SS_THROW__;
                }
                if(verbose)
                    __COUTT__ << "sendAll: resent packet " << missingIdx << std::endl;
 
                if(interPacketGapUSeconds > 0)
                    usleep(interPacketGapUSeconds);
            }
            else
            {
                __COUT_WARN__ << "sendAll: retransmit request for invalid packet index "
                              << missingIdx << " (total=" << totalPackets << ")" << __E__;
            }
        }
    }
 
    return 0;
}  //end sendAll()
 
//==============================================================================
std::string TransceiverSocket::sendAndReceive(
    Socket&            toSocket,
    const std::string& sendBuffer,
    unsigned int       timeoutSeconds /* = 1 */,
    unsigned int       timeoutUSeconds /* = 0 */,
    bool               verbose /* = false */,
    unsigned int       interPacketTimeoutUSeconds /* = 10000 */)
{
    using clock = std::chrono::steady_clock;
    auto start  = clock::now();
 
    // lockout other sender and receive attempts for the remainder of the scope
    std::lock_guard<std::mutex> lock(
        sendAndReceiveMutex_);  //note that TransmitterSocket::sendMutex_ is not enough
 
    flush();  //make sure nothing to read before sending
 
    send(toSocket, sendBuffer, verbose);
 
    __COUTT__ << " ----> Time sendAndReceive '" << sendBuffer
              << "' (socketNumber=" << socketNumber_ << ") check ==> "
              << std::chrono::duration_cast<std::chrono::milliseconds>(clock::now() -
                                                                       start)
                     .count()
              << " milliseconds. PID=" << getpid()
              << " TID=" << std::this_thread::get_id() << std::endl;
 
    std::string receiveBuffer;
    if(receive(receiveBuffer, timeoutSeconds, timeoutUSeconds, verbose) < 0)
    {
        __SS__ << "Timeout (" << timeoutSeconds + timeoutUSeconds / 1000000.
               << " s) or Error receiving response buffer from remote ip:port "
               << toSocket.getIPAddress() << ":" << toSocket.getPort()
               << " to this ip:port " << Socket::getIPAddress() << ":"
               << Socket::getPort() << __E__;
        __SS_ONLY_THROW__;
    }
    __COUTT__ << " ----> Time sendAndReceive '" << sendBuffer << "' got "
              << receiveBuffer.size() << " (socketNumber=" << socketNumber_
              << ") check ==> "
              << std::chrono::duration_cast<std::chrono::milliseconds>(clock::now() -
                                                                       start)
                     .count()
              << " milliseconds. PID=" << getpid()
              << " TID=" << std::this_thread::get_id() << std::endl;
 
    //assume response may be multiple packets! (and give interPacketTimeoutUSeconds unless called with lower timeout)
    size_t      extraPackets = 0;
    std::string receiveBuffer2;
    while(receive(receiveBuffer2,
                  0 /*timeoutSeconds*/,
                  (timeoutSeconds == 0 && timeoutUSeconds < interPacketTimeoutUSeconds)
                      ? timeoutUSeconds
                      : interPacketTimeoutUSeconds,
                  verbose) >= 0)
    {
        ++extraPackets;
        receiveBuffer += receiveBuffer2;  //append
 
        __COUTT__ << " ----> Time sendAndReceive +" << receiveBuffer2.size()
                  << " check ==> "
                  << std::chrono::duration_cast<std::chrono::milliseconds>(clock::now() -
                                                                           start)
                         .count()
                  << " milliseconds." << std::endl;
    }
    __COUTT__ << " ----> Time sendAndReceive " << receiveBuffer.size() << " check ==> "
              << std::chrono::duration_cast<std::chrono::milliseconds>(clock::now() -
                                                                       start)
                     .count()
              << " milliseconds." << std::endl;
 
    return receiveBuffer;
}  //end sendAndReceive()
 
//==============================================================================
int TransceiverSocket::receiveAll(std::string& buffer,
                                  unsigned int timeoutSeconds /* = 5 */,
                                  unsigned int retransmitMaxRetries /* = 10 */,
                                  bool         verbose /* = false */)
{
    using clock = std::chrono::steady_clock;
    auto start  = clock::now();
 
    // Map of packet index -> payload data
    std::map<uint16_t, std::string> receivedPackets;
    uint16_t                        totalPackets = 0;
    bool                            totalKnown   = false;
 
    if(verbose)
        __COUT__ << "receiveAll: waiting for retransmission-mode packets, timeout="
                 << timeoutSeconds << "s" << __E__;
 
    // Phase 1: Receive all initial packets until timeout
    // Use a per-packet timeout that is shorter than the overall timeout,
    // so we can detect "no more packets arriving" vs "still waiting for first"
    const unsigned int interPacketTimeoutUSeconds = 100000;  // 100ms between packets
    bool               firstPacketReceived        = false;
 
    while(true)
    {
        std::string rawPacket;
        int         rc = receive(rawPacket,
                         firstPacketReceived ? 0 : timeoutSeconds,
                         firstPacketReceived ? interPacketTimeoutUSeconds : 0,
                         false /*verbose*/);
 
        if(rc < 0)
        {
            if(!firstPacketReceived)
            {
                // Never received any packet at all
                if(verbose)
                    __COUT__ << "receiveAll: timeout waiting for first packet after "
                             << timeoutSeconds << "s" << __E__;
                return -1;
            }
            // Timeout between packets - move to retransmit phase
            break;
        }
 
        // Check for retransmission header
        if(rawPacket.size() < RETRANSMIT_HEADER_SIZE)
        {
            // Too small to be a retransmission packet - might be a non-retransmit
            // response; just return it as-is
            if(!firstPacketReceived)
            {
                buffer = rawPacket;
                return 0;
            }
            // Skip malformed packet during multi-packet receive
            if(verbose)
                __COUT_WARN__ << "receiveAll: skipping undersized packet ("
                              << rawPacket.size() << " bytes)" << __E__;
            continue;
        }
 
        // Parse header
        uint16_t magic, packetIndex, pktTotal, payloadSize;
        std::memcpy(&magic, rawPacket.data() + 0, 2);
        std::memcpy(&packetIndex, rawPacket.data() + 2, 2);
        std::memcpy(&pktTotal, rawPacket.data() + 4, 2);
        std::memcpy(&payloadSize, rawPacket.data() + 6, 2);
        magic       = ntohs(magic);
        packetIndex = ntohs(packetIndex);
        pktTotal    = ntohs(pktTotal);
        payloadSize = ntohs(payloadSize);
 
        if(magic != RETRANSMIT_MAGIC)
        {
            // Not a retransmission packet - if first packet, return as-is
            if(!firstPacketReceived)
            {
                buffer = rawPacket;
                return 0;
            }
            if(verbose)
                __COUT_WARN__ << "receiveAll: skipping packet with bad magic 0x"
                              << std::hex << magic << std::dec << __E__;
            continue;
        }
 
        firstPacketReceived = true;
        totalPackets        = pktTotal;
        totalKnown          = true;
 
        // Extract payload (everything after the 8-byte header, limited by payloadSize)
        size_t actualPayload = rawPacket.size() - RETRANSMIT_HEADER_SIZE;
        if(actualPayload > payloadSize)
            actualPayload = payloadSize;
 
        receivedPackets[packetIndex] =
            rawPacket.substr(RETRANSMIT_HEADER_SIZE, actualPayload);
 
        if(verbose)
            __COUTT__ << "receiveAll: received packet " << packetIndex << "/"
                      << totalPackets << " payload=" << actualPayload
                      << " total_received=" << receivedPackets.size() << std::endl;
 
        // Check if we have all packets
        if(totalKnown && receivedPackets.size() >= static_cast<size_t>(totalPackets))
            break;
 
        // Check overall timeout
        auto elapsed =
            std::chrono::duration_cast<std::chrono::seconds>(clock::now() - start);
        if(elapsed.count() >=
           static_cast<long>(timeoutSeconds * (retransmitMaxRetries + 1)))
        {
            if(verbose)
                __COUT_WARN__ << "receiveAll: overall timeout reached" << __E__;
            break;
        }
    }
 
    // Phase 2: Retransmit missing packets
    if(totalKnown && receivedPackets.size() < static_cast<size_t>(totalPackets))
    {
        for(unsigned int retry = 0; retry < retransmitMaxRetries; ++retry)
        {
            // Build list of missing packet indices
            std::set<uint16_t> missing;
            for(uint16_t i = 0; i < totalPackets; ++i)
            {
                if(receivedPackets.find(i) == receivedPackets.end())
                    missing.insert(i);
            }
 
            if(missing.empty())
                break;
 
            if(verbose)
                __COUT__ << "receiveAll: retry " << retry + 1 << "/"
                         << retransmitMaxRetries << ", requesting retransmit of "
                         << missing.size() << " packets" << __E__;
 
            // Build retransmit request: magic(2 bytes) + list of uint16 indices
            std::string retransmitReq;
            retransmitReq.resize(2 + missing.size() * 2);
            uint16_t netMagic = htons(RETRANSMIT_MAGIC);
            std::memcpy(&retransmitReq[0], &netMagic, 2);
            size_t pos = 2;
            for(uint16_t idx : missing)
            {
                uint16_t netIdx = htons(idx);
                std::memcpy(&retransmitReq[pos], &netIdx, 2);
                pos += 2;
            }
 
            // Send retransmit request back to sender (acknowledge to last receive addr)
            {
                // Use sendto directly to fromAddress_ (the sender)
                int sendToSize = sendto(socketNumber_,
                                        retransmitReq.data(),
                                        retransmitReq.size(),
                                        0,
                                        (struct sockaddr*)&(ReceiverSocket::fromAddress_),
                                        sizeof(sockaddr_in));
                if(sendToSize <= 0)
                {
                    __COUT_WARN__ << "receiveAll: failed to send retransmit request: "
                                  << strerror(errno) << __E__;
                }
            }
 
            // Receive retransmitted packets
            while(true)
            {
                std::string rawPacket;
                int         rc = receive(
                    rawPacket, timeoutSeconds, 0 /*timeoutUSeconds*/, false /*verbose*/);
                if(rc < 0)
                    break;  // timeout, will retry
 
                if(rawPacket.size() < RETRANSMIT_HEADER_SIZE)
                    continue;
 
                uint16_t magic2, packetIndex2, pktTotal2, payloadSize2;
                std::memcpy(&magic2, rawPacket.data() + 0, 2);
                std::memcpy(&packetIndex2, rawPacket.data() + 2, 2);
                std::memcpy(&pktTotal2, rawPacket.data() + 4, 2);
                std::memcpy(&payloadSize2, rawPacket.data() + 6, 2);
                magic2       = ntohs(magic2);
                packetIndex2 = ntohs(packetIndex2);
                pktTotal2    = ntohs(pktTotal2);
                payloadSize2 = ntohs(payloadSize2);
 
                if(magic2 != RETRANSMIT_MAGIC)
                    continue;
 
                size_t actualPayload2 = rawPacket.size() - RETRANSMIT_HEADER_SIZE;
                if(actualPayload2 > payloadSize2)
                    actualPayload2 = payloadSize2;
 
                receivedPackets[packetIndex2] =
                    rawPacket.substr(RETRANSMIT_HEADER_SIZE, actualPayload2);
 
                if(verbose)
                    __COUTT__ << "receiveAll: retransmit received packet " << packetIndex2
                              << "/" << totalPackets
                              << " total_received=" << receivedPackets.size()
                              << std::endl;
 
                // Check if we now have all packets
                if(receivedPackets.size() >= static_cast<size_t>(totalPackets))
                    break;
            }
 
            if(receivedPackets.size() >= static_cast<size_t>(totalPackets))
                break;
        }
    }
 
    // Phase 3: Send "done" acknowledgment to sender (magic + 0xFFFF)
    {
        std::string doneSignal(4, '\0');
        uint16_t    netMagic = htons(RETRANSMIT_MAGIC);
        uint16_t    netDone  = htons(0xFFFF);
        std::memcpy(&doneSignal[0], &netMagic, 2);
        std::memcpy(&doneSignal[2], &netDone, 2);
        sendto(socketNumber_,
               doneSignal.data(),
               doneSignal.size(),
               0,
               (struct sockaddr*)&(ReceiverSocket::fromAddress_),
               sizeof(sockaddr_in));
    }
 
    // Phase 4: Assemble full buffer in order
    if(!totalKnown || receivedPackets.empty())
    {
        __SS__ << "receiveAll: failed to receive any retransmission-mode packets"
               << __E__;
        __SS_THROW__;
    }
 
    if(receivedPackets.size() < static_cast<size_t>(totalPackets))
    {
        // Build list of still-missing indices for the error message
        std::string missingStr;
        for(uint16_t i = 0; i < totalPackets; ++i)
        {
            if(receivedPackets.find(i) == receivedPackets.end())
            {
                if(!missingStr.empty())
                    missingStr += ", ";
                missingStr += std::to_string(i);
            }
        }
        __SS__ << "receiveAll: failed to receive all packets after "
               << retransmitMaxRetries << " retransmit retries. "
               << "Received " << receivedPackets.size() << "/" << totalPackets
               << " packets. Missing indices: [" << missingStr << "]" << __E__;
        __SS_THROW__;
    }
 
    // Assemble in order
    buffer.clear();
    for(uint16_t i = 0; i < totalPackets; ++i)
        buffer += receivedPackets[i];
 
    if(verbose)
        __COUT__ << "receiveAll: successfully assembled " << buffer.size()
                 << " bytes from " << totalPackets << " packets in "
                 << std::chrono::duration_cast<std::chrono::milliseconds>(clock::now() -
                                                                          start)
                        .count()
                 << " ms" << __E__;
 
    return 0;
}  //end receiveAll()
 
//==============================================================================
std::string TransceiverSocket::sendAndReceiveAll(
    Socket&            toSocket,
    const std::string& sendBuffer,
    unsigned int       timeoutSeconds /* = 5 */,
    unsigned int       retransmitMaxRetries /* = 10 */,
    bool               verbose /* = false */)
{
    using clock = std::chrono::steady_clock;
    auto start  = clock::now();
 
    // lockout other sender and receive attempts for the remainder of the scope
    std::lock_guard<std::mutex> lock(sendAndReceiveMutex_);
 
    flush();  // make sure nothing to read before sending
    send(toSocket, sendBuffer, verbose);
 
    __COUTT__ << " ----> Time sendAndReceiveAll '" << sendBuffer
              << "' (socketNumber=" << socketNumber_ << ") check ==> "
              << std::chrono::duration_cast<std::chrono::milliseconds>(clock::now() -
                                                                       start)
                     .count()
              << " milliseconds. PID=" << getpid()
              << " TID=" << std::this_thread::get_id() << std::endl;
 
    std::string receiveBuffer;
    if(receiveAll(receiveBuffer, timeoutSeconds, retransmitMaxRetries, verbose) < 0)
    {
        __SS__ << "Timeout (" << timeoutSeconds
               << " s) or Error receiving retransmission response from remote ip:port "
               << toSocket.getIPAddress() << ":" << toSocket.getPort()
               << " to this ip:port " << Socket::getIPAddress() << ":"
               << Socket::getPort() << __E__;
        __SS_ONLY_THROW__;
    }
 
    __COUTT__ << " ----> Time sendAndReceiveAll complete: " << receiveBuffer.size()
              << " bytes (socketNumber=" << socketNumber_ << ") ==> "
              << std::chrono::duration_cast<std::chrono::milliseconds>(clock::now() -
                                                                       start)
                     .count()
              << " milliseconds. PID=" << getpid()
              << " TID=" << std::this_thread::get_id() << std::endl;
 
    return receiveBuffer;
}  //end sendAndReceiveAll()