Big-Data-HPC-Platform/common/remote/sockfile.cpp

/*##############################################################################

    HPCC SYSTEMS software Copyright (C) 2012 HPCC Systems®.

    Licensed under the Apache License, Version 2.0 (the "License");
    you may not use this file except in compliance with the License.
    You may obtain a copy of the License at

       http://www.apache.org/licenses/LICENSE-2.0

    Unless required by applicable law or agreed to in writing, software
    distributed under the License is distributed on an "AS IS" BASIS,
    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    See the License for the specific language governing permissions and
    limitations under the License.
############################################################################## */

// todo look at IRemoteFileServer stop


#include "platform.h"
#include "limits.h"

#include "jlib.hpp"
#include "jio.hpp"

#include "jmutex.hpp"
#include "jfile.hpp"
#include "jmisc.hpp"
#include "jthread.hpp"
#include "jqueue.tpp"

#include "securesocket.hpp"
#include "sockfile.hpp"
#include "portlist.h"
#include "jsocket.hpp"
#include "jencrypt.hpp"
#include "jlzw.hpp"
#include "jset.hpp"
#include "jhtree.hpp"

#include "remoteerr.hpp"
#include <atomic>
#include <string>
#include <unordered_map>

#include "rtldynfield.hpp"
#include "rtlds_imp.hpp"
#include "rtlread_imp.hpp"
#include "rtlrecord.hpp"
#include "eclhelper_dyn.hpp"

#include "rtlcommon.hpp"
#include "rtlformat.hpp"

#include "jflz.hpp"
#include "digisign.hpp"

using namespace cryptohelper;


#define SOCKET_CACHE_MAX 500

#define MIN_KEYFILTSUPPORT_VERSION 20

#ifdef _DEBUG
//#define SIMULATE_PACKETLOSS 1
#endif

#define TREECOPYTIMEOUT   (60*60*1000)     // 1Hr (I guess could take longer for big file but at least will stagger)
#define TREECOPYPOLLTIME  (60*1000*5)      // for tracing that delayed
#define TREECOPYPRUNETIME (24*60*60*1000)  // 1 day

static const unsigned __int64 defaultFileStreamChooseNLimit = I64C(0x7fffffffffffffff); // constant should be move to common place (see eclhelper.hpp)
static const unsigned __int64 defaultFileStreamSkipN = 0;
static const unsigned defaultDaFSReplyLimitKB = 1024; // 1MB
enum OutputFormat:byte { outFmt_Binary, outFmt_Xml, outFmt_Json };


#if SIMULATE_PACKETLOSS

#define TESTING_FAILURE_RATE_LOST_SEND  10 // per 1000
#define TESTING_FAILURE_RATE_LOST_RECV  10 // per 1000
#define DUMMY_TIMEOUT_MAX (1000*10)

static bool errorSimulationOn = true;
static ISocket *timeoutreadsock = NULL; // used to trigger


struct dummyReadWrite
{
    class X
    {
        dummyReadWrite *parent;
    public:
        X(dummyReadWrite *_parent)
        {
            parent = _parent;
        }
        ~X()
        {
            delete parent;
        }
    };

    class TimeoutSocketException: public CInterface, public IJSOCK_Exception
    {
    public:
        IMPLEMENT_IINTERFACE;

        TimeoutSocketException()
        {
        }

        virtual ~TimeoutSocketException()
        {
        }

        int errorCode() const { return JSOCKERR_timeout_expired; }
        StringBuffer &  errorMessage(StringBuffer &str) const
        {
            return str.append("timeout expired");
        }
        MessageAudience errorAudience() const
        {
            return MSGAUD_user;
        }
    };


    ISocket *sock;

    dummyReadWrite(ISocket *_sock)
    {
        sock = _sock;
    }

    void readtms(void* buf, size32_t min_size, size32_t max_size, size32_t &size_read, time_t timeout)
    {
        X x(this);
        unsigned t = msTick();
        unsigned r = getRandom();
        bool timeoutread = (timeoutreadsock==sock);
        timeoutreadsock=NULL;
        if (!timeoutread)
            sock->readtms(buf, min_size, max_size, size_read, timeout);
        if (timeoutread||(errorSimulationOn&&(TESTING_FAILURE_RATE_LOST_RECV>0)&&(r%1000<TESTING_FAILURE_RATE_LOST_RECV))) {
            PrintStackReport();
            if (timeoutread)
                PROGLOG("** Simulate timeout");
            else
                PROGLOG("** Simulate Packet loss (size %d,%d)",min_size,max_size);
            if (timeout>DUMMY_TIMEOUT_MAX)
                timeout = DUMMY_TIMEOUT_MAX;
            t = msTick()-t;
            if (t<timeout)
                Sleep(timeout-t);
            IJSOCK_Exception *e = new TimeoutSocketException;
            throw e;
        }
    }
    size32_t write(void const* buf, size32_t size)
    {
        X x(this);
        timeoutreadsock=NULL;
        unsigned r = getRandom();
        if (errorSimulationOn&&(TESTING_FAILURE_RATE_LOST_SEND>0)&&(r%1000<TESTING_FAILURE_RATE_LOST_SEND)) {
            PrintStackReport();
            PROGLOG("** Simulate Packet loss (size %d)",size);
            timeoutreadsock=sock;
            return size;
        }
        return sock->write(buf,size);
    }
};



#define SOCKWRITE(sock) (new dummyReadWrite(sock))->write
#define SOCKREADTMS(sock) (new dummyReadWrite(sock))->readtms
#else
#define SOCKWRITE(sock) sock->write
#define SOCKREADTMS(sock) sock->readtms
#endif

// backward compatible modes
typedef enum { compatIFSHnone, compatIFSHread, compatIFSHwrite, compatIFSHexec, compatIFSHall} compatIFSHmode;

static const char *VERSTRING= "DS V2.4"       // dont forget FILESRV_VERSION in header
#ifdef _WIN32
"Windows ";
#else
"Linux ";
#endif

typedef int RemoteFileIOHandle;

static unsigned maxConnectTime = 0;
static unsigned maxReceiveTime = 0;

//Security and default port attributes
static class _securitySettings
{
public:
    DAFSConnectCfg  connectMethod;
    unsigned short  daFileSrvPort;
    unsigned short  daFileSrvSSLPort;
    const char *    certificate;
    const char *    privateKey;
    const char *    passPhrase;

    _securitySettings()
    {
        queryDafsSecSettings(&connectMethod, &daFileSrvPort, &daFileSrvSSLPort, &certificate, &privateKey, &passPhrase);
    }
} securitySettings;


static CriticalSection              secureContextCrit;
static Owned<ISecureSocketContext>  secureContextServer;
static Owned<ISecureSocketContext>  secureContextClient;

#ifdef _USE_OPENSSL
static ISecureSocket *createSecureSocket(ISocket *sock, SecureSocketType type)
{
    {
        CriticalBlock b(secureContextCrit);
        if (type == ServerSocket)
        {
            if (!secureContextServer)
                secureContextServer.setown(createSecureSocketContextEx(securitySettings.certificate, securitySettings.privateKey, securitySettings.passPhrase, type));
        }
        else if (!secureContextClient)
            secureContextClient.setown(createSecureSocketContext(type));
    }
    int loglevel = SSLogNormal;
#ifdef _DEBUG
    loglevel = SSLogMax;
#endif
    if (type == ServerSocket)
        return secureContextServer->createSecureSocket(sock, loglevel);
    else
        return secureContextClient->createSecureSocket(sock, loglevel);
}
#endif

void clientSetRemoteFileTimeouts(unsigned maxconnecttime,unsigned maxreadtime)
{
    maxConnectTime = maxconnecttime;
    maxReceiveTime = maxreadtime;
}


struct sRFTM
{
    CTimeMon *timemon;
    sRFTM(unsigned limit) {  timemon = limit ? new CTimeMon(limit) : NULL; }
    ~sRFTM() { delete timemon; }
};


const char *remoteServerVersionString() { return VERSTRING; }

static bool AuthenticationEnabled = true;

bool enableDafsAuthentication(bool on)
{
    bool ret = AuthenticationEnabled;
    AuthenticationEnabled = on;
    return ret;
}


#define CLIENT_TIMEOUT      (1000*60*60*12)     // long timeout in case zombies
#define CLIENT_INACTIVEWARNING_TIMEOUT (1000*60*60*12) // time between logging inactive clients
#define SERVER_TIMEOUT      (1000*60*5)         // timeout when waiting for dafilesrv to reply after command
                                                // (increased when waiting for large block)
#define DAFS_CONNECT_FAIL_RETRY_TIME (1000*60*15)
#ifdef SIMULATE_PACKETLOSS
#define NORMAL_RETRIES      (1)
#define LENGTHY_RETRIES     (1)
#else
#define NORMAL_RETRIES      (3)
#define LENGTHY_RETRIES     (12)
#endif

#ifdef _DEBUG
static byte traceFlags=0x30;
#else
static byte traceFlags=0x20;
#endif

#define TF_TRACE (traceFlags&1)
#define TF_TRACE_PRE_IO (traceFlags&2)
#define TF_TRACE_FULL (traceFlags&4)
#define TF_TRACE_CLIENT_CONN (traceFlags&8)
#define TF_TRACE_TREE_COPY (traceFlags&0x10)
#define TF_TRACE_CLIENT_STATS (traceFlags&0x20)


static const unsigned RFEnoerror = 0;

enum
{
    RFCopenIO,                                      // 0
    RFCcloseIO,
    RFCread,
    RFCwrite,
    RFCsize,
    RFCexists,
    RFCremove,
    RFCrename,
    RFCgetver,
    RFCisfile,
    RFCisdirectory,                                 // 10
    RFCisreadonly,
    RFCsetreadonly,
    RFCgettime,
    RFCsettime,
    RFCcreatedir,
    RFCgetdir,
    RFCstop,
    RFCexec,                                        // legacy cmd removed
    RFCdummy1,                                      // legacy placeholder
    RFCredeploy,                                    // 20
    RFCgetcrc,
    RFCmove,
// 1.5 features below
    RFCsetsize,
    RFCextractblobelements,
    RFCcopy,
    RFCappend,
    RFCmonitordir,
    RFCsettrace,
    RFCgetinfo,
    RFCfirewall,    // not used currently          // 30
    RFCunlock,
    RFCunlockreply,
    RFCinvalid,
    RFCcopysection,
// 1.7e
    RFCtreecopy,
// 1.7e - 1
    RFCtreecopytmp,
// 1.8
    RFCsetthrottle, // legacy version
// 1.9
    RFCsetthrottle2,
    RFCsetfileperms,
// 2.0
    RFCreadfilteredindex,    // No longer used     // 40
    RFCreadfilteredindexcount,
    RFCreadfilteredindexblob,
// 2.2
    RFCStreamRead,                                 // 43
// 2.4
    RFCStreamReadTestSocket,                       // 44
    RFCStreamReadJSON = '{',
    RFCmaxnormal,
    RFCmax,
    RFCunknown = 255 // 0 would have been more sensible, but can't break backward compatibility
};

// used by testsocket only
RemoteFileCommandType queryRemoteStreamCmd()
{
    return RFCStreamReadTestSocket;
}


#define RFCText(cmd) #cmd

const char *RFCStrings[] =
{
    RFCText(RFCopenIO),
    RFCText(RFCcloseIO),
    RFCText(RFCread),
    RFCText(RFCwrite),
    RFCText(RFCsize),
    RFCText(RFCexists),
    RFCText(RFCremove),
    RFCText(RFCrename),
    RFCText(RFCgetver),
    RFCText(RFCisfile),
    RFCText(RFCisdirectory),
    RFCText(RFCisreadonly),
    RFCText(RFCsetreadonly),
    RFCText(RFCgettime),
    RFCText(RFCsettime),
    RFCText(RFCcreatedir),
    RFCText(RFCgetdir),
    RFCText(RFCstop),
    RFCText(RFCexec),
    RFCText(RFCdummy1),
    RFCText(RFCredeploy),
    RFCText(RFCgetcrc),
    RFCText(RFCmove),
    RFCText(RFCsetsize),
    RFCText(RFCextractblobelements),
    RFCText(RFCcopy),
    RFCText(RFCappend),
    RFCText(RFCmonitordir),
    RFCText(RFCsettrace),
    RFCText(RFCgetinfo),
    RFCText(RFCfirewall),
    RFCText(RFCunlock),
    RFCText(RFCunlockreply),
    RFCText(RFCinvalid),
    RFCText(RFCcopysection),
    RFCText(RFCtreecopy),
    RFCText(RFCtreecopytmp),
    RFCText(RFCsetthrottle), // legacy version
    RFCText(RFCsetthrottle2),
    RFCText(RFCsetfileperms),
    RFCText(RFCreadfilteredindex),
    RFCText(RFCreadfilteredcount),
    RFCText(RFCreadfilteredblob),
    RFCText(RFCStreamRead),
    RFCText(RFCStreamReadTestSocket),
};
static const char *getRFCText(RemoteFileCommandType cmd)
{
    if (cmd==RFCStreamReadJSON)
        return "RFCStreamReadJSON";
    else
    {
        unsigned elems = sizeof(RFCStrings) / sizeof(RFCStrings[0]);
        if (cmd >= elems)
            return "RFCunknown";
        return RFCStrings[cmd];
    }
}

static const char *getRFSERRText(unsigned err)
{
    switch (err)
    {
        case RFSERR_InvalidCommand:
            return "RFSERR_InvalidCommand";
        case RFSERR_NullFileIOHandle:
            return "RFSERR_NullFileIOHandle";
        case RFSERR_InvalidFileIOHandle:
            return "RFSERR_InvalidFileIOHandle";
        case RFSERR_TimeoutFileIOHandle:
            return "RFSERR_TimeoutFileIOHandle";
        case RFSERR_OpenFailed:
            return "RFSERR_OpenFailed";
        case RFSERR_ReadFailed:
            return "RFSERR_ReadFailed";
        case RFSERR_WriteFailed:
            return "RFSERR_WriteFailed";
        case RFSERR_RenameFailed:
            return "RFSERR_RenameFailed";
        case RFSERR_ExistsFailed:
            return "RFSERR_ExistsFailed";
        case RFSERR_RemoveFailed:
            return "RFSERR_RemoveFailed";
        case RFSERR_CloseFailed:
            return "RFSERR_CloseFailed";
        case RFSERR_IsFileFailed:
            return "RFSERR_IsFileFailed";
        case RFSERR_IsDirectoryFailed:
            return "RFSERR_IsDirectoryFailed";
        case RFSERR_IsReadOnlyFailed:
            return "RFSERR_IsReadOnlyFailed";
        case RFSERR_SetReadOnlyFailed:
            return "RFSERR_SetReadOnlyFailed";
        case RFSERR_GetTimeFailed:
            return "RFSERR_GetTimeFailed";
        case RFSERR_SetTimeFailed:
            return "RFSERR_SetTimeFailed";
        case RFSERR_CreateDirFailed:
            return "RFSERR_CreateDirFailed";
        case RFSERR_GetDirFailed:
            return "RFSERR_GetDirFailed";
        case RFSERR_GetCrcFailed:
            return "RFSERR_GetCrcFailed";
        case RFSERR_MoveFailed:
            return "RFSERR_MoveFailed";
        case RFSERR_ExtractBlobElementsFailed:
            return "RFSERR_ExtractBlobElementsFailed";
        case RFSERR_CopyFailed:
            return "RFSERR_CopyFailed";
        case RFSERR_AppendFailed:
            return "RFSERR_AppendFailed";
        case RFSERR_AuthenticateFailed:
            return "RFSERR_AuthenticateFailed";
        case RFSERR_CopySectionFailed:
            return "RFSERR_CopySectionFailed";
        case RFSERR_TreeCopyFailed:
            return "RFSERR_TreeCopyFailed";
        case RAERR_InvalidUsernamePassword:
            return "RAERR_InvalidUsernamePassword";
        case RFSERR_MasterSeemsToHaveDied:
            return "RFSERR_MasterSeemsToHaveDied";
        case RFSERR_TimeoutWaitSlave:
            return "RFSERR_TimeoutWaitSlave";
        case RFSERR_TimeoutWaitConnect:
            return "RFSERR_TimeoutWaitConnect";
        case RFSERR_TimeoutWaitMaster:
            return "RFSERR_TimeoutWaitMaster";
        case RFSERR_NoConnectSlave:
            return "RFSERR_NoConnectSlave";
        case RFSERR_NoConnectSlaveXY:
            return "RFSERR_NoConnectSlaveXY";
        case RFSERR_VersionMismatch:
            return "RFSERR_VersionMismatch";
        case RFSERR_SetThrottleFailed:
            return "RFSERR_SetThrottleFailed";
        case RFSERR_MaxQueueRequests:
            return "RFSERR_MaxQueueRequests";
        case RFSERR_KeyIndexFailed:
            return "RFSERR_MaxQueueRequests";
        case RFSERR_StreamReadFailed:
            return "RFSERR_StreamReadFailed";
        case RFSERR_InternalError:
            return "Internal Error";
    }
    return "RFSERR_Unknown";
}

unsigned mapDafilesrvixCodes(unsigned err)
{
    // old Solaris dali/remote/daliservix.cpp uses
    // different values for these error codes.
    switch (err)
    {
        case 8200:
            return RFSERR_InvalidCommand;
        case 8201:
            return RFSERR_NullFileIOHandle;
        case 8202:
            return RFSERR_InvalidFileIOHandle;
        case 8203:
            return RFSERR_TimeoutFileIOHandle;
        case 8204:
            return RFSERR_OpenFailed;
        case 8205:
            return RFSERR_ReadFailed;
        case 8206:
            return RFSERR_WriteFailed;
        case 8207:
            return RFSERR_RenameFailed;
        case 8208:
            return RFSERR_SetReadOnlyFailed;
        case 8209:
            return RFSERR_GetDirFailed;
        case 8210:
            return RFSERR_MoveFailed;
    }
    return err;
}

#define ThrottleText(throttleClass) #throttleClass
const char *ThrottleStrings[] =
{
    ThrottleText(ThrottleStd),
    ThrottleText(ThrottleSlow),
};

// very high upper limits that configure can't exceed
#define THROTTLE_MAX_LIMIT 1000000
#define THROTTLE_MAX_DELAYMS 3600000
#define THROTTLE_MAX_CPUTHRESHOLD 100
#define THROTTLE_MAX_QUEUELIMIT 10000000

static const char *getThrottleClassText(ThrottleClass throttleClass) { return ThrottleStrings[throttleClass]; }

typedef enum { ACScontinue, ACSdone, ACSerror} AsyncCommandStatus;



typedef byte OnceKey[16];

static void genOnce(OnceKey &key)
{
    static __int64 inc=0;
    *(unsigned *)&key[0] = getRandom();
    *(__int64 *)&key[4] = ++inc;
    *(unsigned *)&key[12] = getRandom();
}

static void mergeOnce(OnceKey &key,size32_t sz,const void *data)
{
    assertex(sz<=sizeof(OnceKey));
    const byte *p = (const byte *)data;
    while (sz)
        key[--sz] ^= *(p++);
}

//---------------------------------------------------------------------------

class DECL_EXCEPTION CDafsException: public IDAFS_Exception, public CInterface
{
    int     errcode;
    StringAttr msg;
public:
    IMPLEMENT_IINTERFACE;

    CDafsException(int code,const char *_msg)
        : errcode(code), msg(_msg)
    {
    };

    int errorCode() const
    {
        return errcode;
    }

    StringBuffer &  errorMessage(StringBuffer &str) const
    {
        return str.append(msg);
    }
    MessageAudience errorAudience() const
    {
        return MSGAUD_user;
    }
};

static IDAFS_Exception *createDafsException(int code, const char *msg)
{
    return new CDafsException(code, msg);
}

static IDAFS_Exception *createDafsExceptionVA(int code, const char *format, va_list args)
{
    StringBuffer eStr;
    eStr.limited_valist_appendf(1024, format, args);
    return new CDafsException(code, eStr);
}

static IDAFS_Exception *createDafsExceptionV(int code, const char *format, ...)
{
    va_list args;
    va_start(args, format);
    IDAFS_Exception *ret = createDafsExceptionVA(code, format, args);
    va_end(args);
    return ret;
}

void setDafsEndpointPort(SocketEndpoint &ep)
{
    // odd kludge (don't do this at home)
    byte ipb[4];
    if (ep.getNetAddress(sizeof(ipb),&ipb)==sizeof(ipb)) {
        if ((ipb[0]==255)&&(ipb[1]==255)) {
            ep.port = (((unsigned)ipb[2])<<8)+ipb[3];
            ep.ipset(queryLocalIP());
        }
    }
    if (ep.port==0)
    {
        if ( (securitySettings.connectMethod == SSLNone) || (securitySettings.connectMethod == UnsecureFirst) )
            ep.port = securitySettings.daFileSrvPort;
        else
            ep.port = securitySettings.daFileSrvSSLPort;
    }
}


inline MemoryBuffer & initSendBuffer(MemoryBuffer & buff)
{
    buff.setEndian(__BIG_ENDIAN);       // transfer as big endian...
    buff.append((unsigned)0);           // reserve space for length prefix
    return buff;
}

inline void sendBuffer(ISocket * socket, MemoryBuffer & src, bool testSocketFlag=false)
{
    unsigned length = src.length() - sizeof(unsigned);
    byte * buffer = (byte *)src.toByteArray();
    if (TF_TRACE_FULL)
        PROGLOG("sendBuffer size %d, data = %d %d %d %d",length, (int)buffer[4],(int)buffer[5],(int)buffer[6],(int)buffer[7]);
    if (testSocketFlag)
        length |= 0x80000000;
    _WINCPYREV(buffer, &length, sizeof(unsigned));
    SOCKWRITE(socket)(buffer, src.length());
}

inline size32_t receiveBufferSize(ISocket * socket, unsigned numtries=NORMAL_RETRIES,CTimeMon *timemon=NULL)
{
    unsigned timeout = SERVER_TIMEOUT;
    if (numtries==0) {
        numtries = 1;
        timeout = 10*1000;  // 10s
    }
    while (numtries--) {
        try {
            if (timemon) {
                unsigned remaining;
                if (timemon->timedout(&remaining)||(remaining<10))
                    remaining = 10;
                if (remaining<timeout)
                    timeout = remaining;
            }
            size32_t szread;
            size32_t gotLength;
            SOCKREADTMS(socket)(&gotLength, sizeof(gotLength), sizeof(gotLength), szread, timeout);
            _WINREV(gotLength);
            if (TF_TRACE_FULL)
                PROGLOG("receiveBufferSized %d",gotLength);
            return gotLength;
        }
        catch (IJSOCK_Exception *e) {
            if ((numtries==0)||(e->errorCode()!=JSOCKERR_timeout_expired)||(timemon&&timemon->timedout())) {
                throw;
            }
            StringBuffer err;
            char peername[256];
            socket->peer_name(peername,sizeof(peername)-1);
            WARNLOG("Remote connection %s: %s",peername,e->errorMessage(err).str()); // why no peername
            e->Release();
            Sleep(500+getRandom()%1000); // ~1s
        }
    }
    return 0;
}

static void flush(ISocket *socket)
{
    MemoryBuffer sendbuf;
    initSendBuffer(sendbuf);
    sendbuf.append((RemoteFileCommandType)RFCgetver);
    sendbuf.append((unsigned)RFCgetver);
    MemoryBuffer reply;
    size32_t totread=0;
    try
    {
        sendBuffer(socket, sendbuf);
        char buf[1024];
        for (;;)
        {
            Sleep(1000);    // breathe
            size32_t szread;
            SOCKREADTMS(socket)(buf, 1, sizeof(buf), szread, 1000*60);
            totread += szread;
        }
    }
    catch (IJSOCK_Exception *e) {
        if (totread)
            PROGLOG("%d bytes discarded",totread);
        if (e->errorCode()!=JSOCKERR_timeout_expired)
            EXCLOG(e,"flush");
        e->Release();
    }
}

inline void receiveBuffer(ISocket * socket, MemoryBuffer & tgt, unsigned numtries=1, size32_t maxsz=0x7fffffff)
    // maxsz is a guess at a resonable upper max to catch where protocol error
{
    sRFTM tm(maxReceiveTime);
    size32_t gotLength = receiveBufferSize(socket, numtries,tm.timemon);
    if (gotLength) {
        size32_t origlen = tgt.length();
        try {
            if (gotLength>maxsz) {
                StringBuffer msg;
                msg.appendf("receiveBuffer maximum block size exceeded %d/%d",gotLength,maxsz);
                PrintStackReport();
                throw createDafsException(DAFSERR_protocol_failure,msg.str());
            }
            unsigned timeout = SERVER_TIMEOUT*(numtries?numtries:1);
            if (tm.timemon) {
                unsigned remaining;
                if (tm.timemon->timedout(&remaining)||(remaining<10))
                    remaining = 10;
                if (remaining<timeout)
                    timeout = remaining;
            }
            size32_t szread;
            SOCKREADTMS(socket)((gotLength<4000)?tgt.reserve(gotLength):tgt.reserveTruncate(gotLength), gotLength, gotLength, szread, timeout);
        }
        catch (IJSOCK_Exception *e) {
            if (e->errorCode()!=JSOCKERR_timeout_expired) {
                EXCLOG(e,"receiveBuffer(1)");
                PrintStackReport();
                if (!tm.timemon||!tm.timemon->timedout())
                    flush(socket);
            }
            else {
                EXCLOG(e,"receiveBuffer");
                PrintStackReport();
            }
            tgt.setLength(origlen);
            throw;
        }
        catch (IException *e) {
            EXCLOG(e,"receiveBuffer(2)");
            PrintStackReport();
            if (!tm.timemon||!tm.timemon->timedout())
                flush(socket);
            tgt.setLength(origlen);
            throw;
        }

    }
    tgt.setEndian(__BIG_ENDIAN);
}


struct CConnectionRec
{
    SocketEndpoint ep;
    unsigned tick;
    IArrayOf<ISocket> socks;            // relies on isShared
};

//---------------------------------------------------------------------------
// Local mount redirect

struct CLocalMountRec: public CInterface
{
    IpAddress ip;
    StringAttr dir;             // dir path on remote ip
    StringAttr local;           // local dir path
};

static CIArrayOf<CLocalMountRec> localMounts;
static CriticalSection           localMountCrit;

void setDafsLocalMountRedirect(const IpAddress &ip,const char *dir,const char *mountdir)
{
    CriticalBlock block(localMountCrit);
    ForEachItemInRev(i,localMounts) {
        CLocalMountRec &mount = localMounts.item(i);
        if (dir==NULL) { // remove all matching mount
            if (!mountdir)
                return;
            if (strcmp(mount.local,mountdir)==0)
                localMounts.remove(i);
        }
        else if (mount.ip.ipequals(ip)&&(strcmp(mount.dir,dir)==0)) {
            if (mountdir) {
                mount.local.set(mountdir);
                return;
            }
            else
                localMounts.remove(i);
        }
    }
    if (dir&&mountdir) {
        CLocalMountRec &mount = *new CLocalMountRec;
        mount.ip.ipset(ip);
        mount.dir.set(dir);
        mount.local.set(mountdir);
        localMounts.append(mount);
    }
}

IFile *createFileLocalMount(const IpAddress &ip, const char * filename)
{
    CriticalBlock block(localMountCrit);
    ForEachItemInRev(i,localMounts) {
        CLocalMountRec &mount = localMounts.item(i);
        if (mount.ip.ipequals(ip)) {
            size32_t bl = mount.dir.length();
            if (isPathSepChar(mount.dir[bl-1]))
                bl--;
            if ((memcmp((void *)filename,(void *)mount.dir.get(),bl)==0)&&(isPathSepChar(filename[bl])||!filename[bl])) { // match
                StringBuffer locpath(mount.local);
                if (filename[bl])
                    addPathSepChar(locpath).append(filename+bl+1);
                locpath.replace((PATHSEPCHAR=='\\')?'/':'\\',PATHSEPCHAR);
                return createIFile(locpath.str());
            }
        }
    }
    return NULL;
}


//---------------------------------------------------------------------------


static class CConnectionTable: public SuperHashTableOf<CConnectionRec,SocketEndpoint>
{

    void onAdd(void *) {}

    void onRemove(void *e)
    {
        CConnectionRec *r=(CConnectionRec *)e;
        delete r;
    }

    unsigned getHashFromElement(const void *e) const
    {
        const CConnectionRec &elem=*(const CConnectionRec *)e;
        return elem.ep.hash(0);
    }

    unsigned getHashFromFindParam(const void *fp) const
    {
        return ((const SocketEndpoint *)fp)->hash(0);
    }

    const void * getFindParam(const void *p) const
    {
        const CConnectionRec &elem=*(const CConnectionRec *)p;
        return (void *)&elem.ep;
    }

    bool matchesFindParam(const void * et, const void *fp, unsigned) const
    {
        return ((CConnectionRec *)et)->ep.equals(*(SocketEndpoint *)fp);
    }

    IMPLEMENT_SUPERHASHTABLEOF_REF_FIND(CConnectionRec,SocketEndpoint);

    unsigned numsockets;

public:
    static CriticalSection crit;

    CConnectionTable()
    {
        numsockets = 0;
    }
    ~CConnectionTable() {
        _releaseAll();
    }

    ISocket *lookup(const SocketEndpoint &ep)
    {
        // always called from crit block
        CConnectionRec *r = SuperHashTableOf<CConnectionRec,SocketEndpoint>::find(&ep);
        if (r) {
            ForEachItemIn(i,r->socks) {
                ISocket *s = &r->socks.item(i);
                if (!QUERYINTERFACE(s, CInterface)->IsShared()) {
                    r->tick = msTick();
                    s->Link();
                    return s;
                }
            }
        }
        return NULL;
    }

    void addLink(SocketEndpoint &ep,ISocket *sock)
    {
        // always called from crit block
        while (numsockets>=SOCKET_CACHE_MAX) {
            // find oldest
            CConnectionRec *c = NULL;
            unsigned oldest = 0;
            CConnectionRec *old = NULL;
            unsigned oldi;
            unsigned now = msTick();
            for (;;) {
                c = (CConnectionRec *)SuperHashTableOf<CConnectionRec,SocketEndpoint>::next(c);
                if (!c)
                    break;
                ForEachItemIn(i,c->socks) {
                    ISocket *s = &c->socks.item(i);
                    if (!QUERYINTERFACE(s, CInterface)->IsShared()) { // candidate to remove
                        unsigned t = now-c->tick;
                        if (t>oldest) {
                            oldest = t;
                            old = c;
                            oldi = i;
                        }
                    }
                }
            }
            if (!old)
                return;
            old->socks.remove(oldi);
            numsockets--;
        }
        CConnectionRec *r = SuperHashTableOf<CConnectionRec,SocketEndpoint>::find(&ep);
        if (!r) {
            r = new CConnectionRec;
            r->ep = ep;
            SuperHashTableOf<CConnectionRec,SocketEndpoint>::add(*r);
        }
        sock->Link();
        r->socks.append(*sock);
        numsockets++;
        r->tick = msTick();
    }

    void remove(SocketEndpoint &ep,ISocket *sock)
    {
        // always called from crit block
        CConnectionRec *r = SuperHashTableOf<CConnectionRec,SocketEndpoint>::find(&ep);
        if (r)
            if (r->socks.zap(*sock)&&numsockets)
                numsockets--;

    }


} *ConnectionTable = NULL;


CriticalSection CConnectionTable::crit;

void clientSetDaliServixSocketCaching(bool on)
{
    CriticalBlock block(CConnectionTable::crit);
    if (on) {
        if (!ConnectionTable)
            ConnectionTable = new CConnectionTable;
    }
    else {
        delete ConnectionTable;
        ConnectionTable = NULL;
    }
}

//---------------------------------------------------------------------------

// TreeCopy

#define TREECOPY_CACHE_SIZE 50

struct CTreeCopyItem: public CInterface
{
    StringAttr net;
    StringAttr mask;
    offset_t sz;                // original size
    CDateTime dt;               // original date
    RemoteFilenameArray loc;    // locations for file - 0 is original
    Owned<IBitSet> busy;
    unsigned lastused;

    CTreeCopyItem(RemoteFilename &orig, const char *_net, const char *_mask, offset_t _sz, CDateTime &_dt)
        : net(_net), mask(_mask)
    {
        loc.append(orig);
        dt.set(_dt);
        sz = _sz;
        busy.setown(createThreadSafeBitSet());
        lastused = msTick();
    }
    bool equals(const RemoteFilename &orig, const char *_net, const char *_mask, offset_t _sz, CDateTime &_dt)
    {
        if (!orig.equals(loc.item(0)))
            return false;
        if (strcmp(_net,net)!=0)
            return false;
        if (strcmp(_mask,mask)!=0)
            return false;
        if (sz!=_sz)
            return false;
        return (dt.equals(_dt,false));
    }
};

static CIArrayOf<CTreeCopyItem>  treeCopyArray;
static CriticalSection           treeCopyCrit;
static unsigned                  treeCopyWaiting=0;
static Semaphore                 treeCopySem;

#define DEBUGSAMEIP false

static void cleanupSocket(ISocket *sock)
{
    if (!sock)
        return;
    try
    {
        sock->shutdown();
    }
    catch (IException *e)
    {
        e->Release();
    }
    try
    {
        sock->close();
    }
    catch (IException *e)
    {
        e->Release();
    }
}

//---------------------------------------------------------------------------

class CRemoteBase: public CInterface
{
    Owned<ISocket>          socket;
    static  SocketEndpoint  lastfailep;
    static unsigned         lastfailtime;
    DAFSConnectCfg          connectMethod;

    void connectSocket(SocketEndpoint &ep, unsigned localConnectTime=0, unsigned localRetries=0)
    {
        unsigned retries = 3;

        if (localConnectTime)
        {
            if (localRetries)
                retries = localRetries;
            if (localConnectTime > maxConnectTime)
                localConnectTime = maxConnectTime;
        }
        else
            localConnectTime = maxConnectTime;

        sRFTM tm(localConnectTime);

        // called in CConnectionTable::crit

        if (ep.equals(lastfailep)) {
            if (msTick()-lastfailtime<DAFS_CONNECT_FAIL_RETRY_TIME) {
                StringBuffer msg("Failed to connect (host marked down) to dafilesrv/daliservix on ");
                ep.getUrlStr(msg);
                throw createDafsException(DAFSERR_connection_failed,msg.str());
            }
            lastfailep.set(NULL);
            retries = 1;    // on probation
        }
        while(retries--) {
            CriticalUnblock unblock(CConnectionTable::crit); // allow others to connect
            StringBuffer eps;
            if (TF_TRACE_CLIENT_CONN) {
                ep.getUrlStr(eps);
                if (ep.port == securitySettings.daFileSrvSSLPort)
                    PROGLOG("Connecting SECURE to %s", eps.str());
                else
                    PROGLOG("Connecting to %s", eps.str());
                //PrintStackReport();
            }
            bool ok = true;
            try {
                if (tm.timemon) {
                    unsigned remaining;
                    if (tm.timemon->timedout(&remaining))
                        throwJSocketException(JSOCKERR_connection_failed);
                    socket.setown(ISocket::connect_timeout(ep,remaining));
                }
                else
                    socket.setown(ISocket::connect(ep));
                if (ep.port == securitySettings.daFileSrvSSLPort)
                {
#ifdef _USE_OPENSSL
                    Owned<ISecureSocket> ssock;
                    try
                    {
                        ssock.setown(createSecureSocket(socket.getClear(), ClientSocket));
                        int status = ssock->secure_connect();
                        if (status < 0)
                            throw createDafsException(DAFSERR_connection_failed, "Failure to establish secure connection");
                        socket.setown(ssock.getLink());
                    }
                    catch (IException *e)
                    {
                        cleanupSocket(ssock);
                        ssock.clear();
                        cleanupSocket(socket);
                        socket.clear();
                        StringBuffer eMsg;
                        e->errorMessage(eMsg);
                        e->Release();
                        throw createDafsException(DAFSERR_connection_failed, eMsg.str());
                    }
#else
                    throw createDafsException(DAFSERR_connection_failed,"Failure to establish secure connection: OpenSSL disabled in build");
#endif
                }
            }
            catch (IJSOCK_Exception *e) {
                ok = false;
                if (!retries||(tm.timemon&&tm.timemon->timedout())) {
                    if (e->errorCode()==JSOCKERR_connection_failed) {
                        lastfailep.set(ep);
                        lastfailtime = msTick();
                        e->Release();
                        StringBuffer msg("Failed to connect (setting host down) to dafilesrv/daliservix on ");
                        ep.getUrlStr(msg);
                        throw createDafsException(DAFSERR_connection_failed,msg.str());
                    }
                    throw;
                }
                StringBuffer err;
                WARNLOG("Remote file connect %s",e->errorMessage(err).str());
                e->Release();
            }
            if (ok) {
                if (TF_TRACE_CLIENT_CONN) {
                    PROGLOG("Connected to %s",eps.str());
                }
                if (AuthenticationEnabled) {
                    try {
                        sendAuthentication(ep); // this will log error
                        break;
                    }
                    catch (IJSOCK_Exception *e) {
                        StringBuffer err;
                        WARNLOG("Remote file authenticate %s for %s ",e->errorMessage(err).str(),ep.getUrlStr(eps.clear()).str());
                        e->Release();
                        if (!retries)
                            break; // MCK - is this a warning or an error ? If an error, should we close and throw here ?
                    }
                }
                else
                    break;
            }
            bool timeExpired = false;
            unsigned sleeptime = getRandom()%3000+1000;
            if (tm.timemon)
            {
                unsigned remaining;
                if (tm.timemon->timedout(&remaining))
                    timeExpired = true;
                else
                {
                    if (remaining/2<sleeptime)
                        sleeptime = remaining/2;
                }
            }
            if (!timeExpired)
            {
                Sleep(sleeptime);       // prevent multiple retries beating
                if (ep.port == securitySettings.daFileSrvSSLPort)
                    PROGLOG("Retrying SECURE connect");
                else
                    PROGLOG("Retrying connect");
            }
        }
        if (ConnectionTable)
            ConnectionTable->addLink(ep,socket);
    }

    void killSocket(SocketEndpoint &tep)
    {
        CriticalBlock block2(CConnectionTable::crit); // this is nested with crit
        if (socket) {
            try {
                Owned<ISocket> s = socket.getClear();
                if (ConnectionTable)
                    ConnectionTable->remove(tep,s);
            }
            catch (IJSOCK_Exception *e) {
                e->Release();   // ignore errors closing
            }
            Sleep(getRandom()%1000*5+500);      // prevent multiple beating
        }
    }

protected: friend class CRemoteFileIO;


    StringAttr          filename;
    CriticalSection     crit;
    SocketEndpoint      ep;


    void sendRemoteCommand(MemoryBuffer & src, MemoryBuffer & reply, bool retry=true, bool lengthy=false, bool handleErrCode=true)
    {
        CriticalBlock block(crit);  // serialize commands on same file
        SocketEndpoint tep(ep);
        setDafsEndpointPort(tep);
        unsigned nretries = retry?3:0;
        Owned<IJSOCK_Exception> firstexc;   // when retrying return first error if fails
        for (;;)
        {
            try
            {
                if (socket)
                {
                    sendBuffer(socket, src);
                    receiveBuffer(socket, reply, lengthy?LENGTHY_RETRIES:NORMAL_RETRIES);
                    break;
                }
            }
            catch (IJSOCK_Exception *e)
            {
                if (!nretries--)
                {
                    if (firstexc)
                    {
                        e->Release();
                        e = firstexc.getClear();
                    }
                    killSocket(tep);
                    throw e;
                }
                StringBuffer str;
                e->errorMessage(str);
                WARNLOG("Remote File: %s, retrying (%d)",str.str(),nretries);
                if (firstexc)
                    e->Release();
                else
                    firstexc.setown(e);
                killSocket(tep);
            }
            CriticalBlock block2(CConnectionTable::crit); // this is nested with crit
            if (ConnectionTable)
            {
                socket.setown(ConnectionTable->lookup(tep));
                if (socket)
                {
                    // validate existing socket by sending an 'exists' command with short time out
                    // (use exists for backward compatibility)
                    bool ok = false;
                    try
                    {
                        MemoryBuffer sendbuf;
                        initSendBuffer(sendbuf);
                        MemoryBuffer replybuf;
                        sendbuf.append((RemoteFileCommandType)RFCexists).append(filename);
                        sendBuffer(socket, sendbuf);
                        receiveBuffer(socket, replybuf, 0, 1024);
                        ok = true;
                    }
                    catch (IException *e) {
                        e->Release();
                    }
                    if (!ok)
                        killSocket(tep);
                }
            }

            if (!socket)
            {
                bool doConnect = true;
                if (connectMethod == SSLFirst || connectMethod == UnsecureFirst)
                {
                    // MCK - could maintain a list of 100 or so previous endpoints and if connection failed
                    // then mark port down for a delay (like 15 min above) to avoid having to try every time ...
                    try
                    {
                        connectSocket(tep, 5000, 1);
                        doConnect = false;
                    }
                    catch (IDAFS_Exception *e)
                    {
                        if (e->errorCode() == DAFSERR_connection_failed)
                        {
                            unsigned prevPort = tep.port;
                            if (prevPort == securitySettings.daFileSrvSSLPort)
                                tep.port = securitySettings.daFileSrvPort;
                            else
                                tep.port = securitySettings.daFileSrvSSLPort;
                            WARNLOG("Connect failed on port %d, retrying on port %d", prevPort, tep.port);
                            doConnect = true;
                            e->Release();
                        }
                        else
                            throw e;
                    }
                }
                if (doConnect)
                    connectSocket(tep);
            }
        }

        if (!handleErrCode)
            return;
        unsigned errCode;
        reply.read(errCode);
        if (errCode)
        {
            // old Solaris daliservix.cpp error code conversion
            if ( (errCode >= 8200) && (errCode <= 8210) )
                errCode = mapDafilesrvixCodes(errCode);
            StringBuffer msg;
            if (filename.get())
                msg.append(filename);
            ep.getUrlStr(msg.append('[')).append("] ");
            size32_t pos = reply.getPos();
            if (pos<reply.length())
            {
                size32_t len = reply.length()-pos;
                const byte *rest = reply.readDirect(len);
                if (errCode==RFSERR_InvalidCommand)
                {
                    const char *s = (const char *)rest;
                    const char *e = (const char *)rest+len;
                    while (*s&&(s!=e))
                        s++;
                    msg.append(s-(const char *)rest,(const char *)rest);
                }
                else if (len&&(rest[len-1]==0))
                    msg.append((const char *)rest);
                else
                {
                    msg.appendf("extra data[%d]",len);
                    for (unsigned i=0;(i<16)&&(i<len);i++)
                        msg.appendf(" %2x",(int)rest[i]);
                }
            }
            // NB: could append getRFSERRText for all error codes
            else if (errCode == RFSERR_GetDirFailed)
                msg.append(RFSERR_GetDirFailed_Text);
            else
                msg.append("ERROR #").append(errCode);
#ifdef _DEBUG
            ERRLOG("%s",msg.str());
            PrintStackReport();
#endif
            throw createDafsException(errCode,msg.str());
        }
    }

    void sendRemoteCommand(MemoryBuffer & src, bool retry)
    {
        MemoryBuffer reply;
        sendRemoteCommand(src, reply, retry);
    }

    void throwUnauthenticated(const IpAddress &ip,const char *user,unsigned err=0)
    {
        if (err==0)
            err = RFSERR_AuthenticateFailed;
        StringBuffer msg;
        msg.appendf("Authentication for %s on ",user);
        ip.getIpText(msg);
        msg.append(" failed");
        throw createDafsException(err, msg.str());
    }

    void sendAuthentication(const IpAddress &serverip)
    {
        // send my sig
        // first send my sig which if stream unencrypted will get returned as a bad command
        OnceKey oncekey;
        genOnce(oncekey);
        MemoryBuffer sendbuf;
        initSendBuffer(sendbuf);
        MemoryBuffer replybuf;
        MemoryBuffer encbuf; // because aesEncrypt clears input
        sendbuf.append((RemoteFileCommandType)RFCunlock).append(sizeof(oncekey),&oncekey);
        try
        {
            sendBuffer(socket, sendbuf);
            receiveBuffer(socket, replybuf, NORMAL_RETRIES, 1024);
        }
        catch (IException *e)
        {
            EXCLOG(e,"Remote file - sendAuthentication(1)");
            throw;
        }
        unsigned errCode;
        replybuf.read(errCode);
        if (errCode!=0)  // no authentication required
            return;
        SocketEndpoint ep;
        ep.setLocalHost(0);
        byte ipdata[16];
        size32_t ipds = ep.getNetAddress(sizeof(ipdata),&ipdata);
        mergeOnce(oncekey,ipds,&ipdata);
        StringBuffer username;
        StringBuffer password;
        IPasswordProvider * pp = queryPasswordProvider();
        if (pp)
            pp->getPassword(serverip, username, password);
        if (!username.length())
            username.append("sds_system");      // default account (note if exists should have restricted access!)
        if (!password.length())
            password.append("sds_man");
        if (replybuf.remaining()<=sizeof(size32_t))
            throwUnauthenticated(serverip,username.str());
        size32_t bs;
        replybuf.read(bs);
        if (replybuf.remaining()<bs)
            throwUnauthenticated(serverip,username.str());
        MemoryBuffer skeybuf;
        aesDecrypt(&oncekey,sizeof(oncekey),replybuf.readDirect(bs),bs,skeybuf);
        if (skeybuf.remaining()<sizeof(OnceKey))
            throwUnauthenticated(serverip,username.str());
        OnceKey sokey;
        skeybuf.read(sizeof(OnceKey),&sokey);
        // now we have the key to use to send user/password
        MemoryBuffer tosend;
        tosend.append((byte)2).append(username).append(password);
        initSendBuffer(sendbuf.clear());
        sendbuf.append((RemoteFileCommandType)RFCunlockreply);
        aesEncrypt(&sokey, sizeof(oncekey), tosend.toByteArray(), tosend.length(), encbuf);
        sendbuf.append(encbuf.length());
        sendbuf.append(encbuf);
        try
        {
            sendBuffer(socket, sendbuf);
            receiveBuffer(socket, replybuf.clear(), NORMAL_RETRIES, 1024);
        }
        catch (IException *e)
        {
            EXCLOG(e,"Remote file - sendAuthentication(2)");
            throw;
        }
        replybuf.read(errCode);
        if (errCode==0)  // suceeded!
            return;
        throwUnauthenticated(serverip,username.str(),errCode);
    }

public:
    SocketEndpoint  &queryEp() { return ep; };


    CRemoteBase(const SocketEndpoint &_ep, const char * _filename)
        : filename(_filename)
    {
        ep = _ep;
        connectMethod = securitySettings.connectMethod;
    }

    void disconnect()
    {
        CriticalBlock block(crit);
        CriticalBlock block2(CConnectionTable::crit); // this shouldn't ever block
        if (socket)
        {
            ISocket *s = socket.getClear();
            if (ConnectionTable)
            {
                SocketEndpoint tep(ep);
                setDafsEndpointPort(tep);
                ConnectionTable->remove(tep,s);
            }
            ::Release(s);
        }
    }

    const char *queryLocalName()
    {
        return filename;
    }

};

SocketEndpoint  CRemoteBase::lastfailep;
unsigned CRemoteBase::lastfailtime;


//---------------------------------------------------------------------------

class CRemoteDirectoryIterator : implements IDirectoryDifferenceIterator, public CInterface
{
    Owned<IFile>    cur;
    bool            curvalid;
    bool            curisdir;
    StringAttr      curname;
    CDateTime       curdt;
    __int64         cursize;
    StringAttr      dir;
    SocketEndpoint  ep;
    byte            *flags;
    unsigned        numflags;
    unsigned        curidx;
    unsigned        mask;

    MemoryBuffer buf;
public:
    static CriticalSection      crit;

    CRemoteDirectoryIterator(SocketEndpoint &_ep,const char *_dir)
        : dir(_dir)
    {
        // an extended difference iterator starts with 2 (for bwd compatibility)
        ep = _ep;
        curisdir = false;
        curvalid = false;
        cursize = 0;
        curidx = (unsigned)-1;
        mask = 0;
        numflags = 0;
        flags = NULL;
    }

    bool appendBuf(MemoryBuffer &_buf)
    {
        buf.setSwapEndian(_buf.needSwapEndian());
        byte hdr;
        _buf.read(hdr);
        if (hdr==2) {
            _buf.read(numflags);
            flags = (byte *)malloc(numflags);
            _buf.read(numflags,flags);
        }
        else {
            buf.append(hdr);
            flags = NULL;
            numflags = 0;
        }
        size32_t rest = _buf.length()-_buf.getPos();
        const byte *rb = (const byte *)_buf.readDirect(rest);
        bool ret = true;
        // At the last byte of the rb (rb[rest-1]) is the stream live flag
        //  True if the stream has more data
        //  False at the end of stream
        // The previous byte (rb[rest-2]) is the flag to signal there are more
        // valid entries in this block
        //  True if there are valid directory entry follows this flag
        //  False if there are no more valid entry in this block aka end of block
        // If there is more data in the stream, the end of block flag should be removed
        if (rest&&(rb[rest-1]!=0))
        {
            rest--; // remove stream live flag
            if(rest && (0 == rb[rest-1]))
            	rest--; //Remove end of block flag
            ret = false;  // continuation
        }
        buf.append(rest,rb);
        return ret;
    }

    ~CRemoteDirectoryIterator()
    {
        free(flags);
    }

    IMPLEMENT_IINTERFACE

    bool first()
    {
        curidx = (unsigned)-1;
        buf.reset();
        return next();
    }
    bool next()
    {
        for (;;) {
            curidx++;
            cur.clear();
            curdt.clear();
            curname.clear();
            cursize = 0;
            curisdir = false;
            if (buf.getPos()>=buf.length())
                return false;
            byte isValidEntry;
            buf.read(isValidEntry);
            curvalid = isValidEntry!=0;
            if (!curvalid)
                return false;
            buf.read(curisdir);
            buf.read(cursize);
            curdt.deserialize(buf);
            buf.read(curname);
            // kludge for bug in old linux jlibs
            if (strchr(curname,'\\')&&(getPathSepChar(dir)=='/')) {
                StringBuffer temp(curname);
                temp.replace('\\','/');
                curname.set(temp.str());
            }
            if ((mask==0)||(getFlags()&mask))
                break;
        }
        return true;
    }

    bool isValid()
    {
        return curvalid;
    }
    IFile & query()
    {
        if (!cur) {
            StringBuffer full(dir);
            addPathSepChar(full).append(curname);
            if (ep.isNull())
                cur.setown(createIFile(full.str()));
            else {
                RemoteFilename rfn;
                rfn.setPath(ep,full.str());
                cur.setown(createIFile(rfn));
            }
        }
        return *cur;
    }
    StringBuffer &getName(StringBuffer &buf)
    {
        return buf.append(curname);
    }
    bool isDir()
    {
        return curisdir;
    }

    __int64 getFileSize()
    {
        if (curisdir)
            return -1;
        return cursize;
    }


    bool getModifiedTime(CDateTime &ret)
    {
        ret = curdt;
        return true;
    }

    void setMask(unsigned _mask)
    {
        mask = _mask;
    }

    virtual unsigned getFlags()
    {
        if (flags&&(curidx<numflags))
            return flags[curidx];
        return 0;
    }

    static bool serialize(MemoryBuffer &mb,IDirectoryIterator *iter, size32_t bufsize, bool first)
    {
        bool ret = true;
        byte b=1;
        StringBuffer tmp;
        if (first ? iter->first() : iter->next()) {
            for (;;) {
                mb.append(b);
                bool isdir = iter->isDir();
                __int64 sz = isdir?0:iter->getFileSize();
                CDateTime dt;
                iter->getModifiedTime(dt);
                iter->getName(tmp.clear());
                mb.append(isdir).append(sz);
                dt.serialize(mb);
                mb.append(tmp.str());
                if (bufsize&&(mb.length()>=bufsize-1)) {
                    ret = false;
                    break;
                }
                if (!iter->next())
                    break;
            }
        }
        b = 0;
        mb.append(b);
        return ret;
    }

    static void serializeDiff(MemoryBuffer &mb,IDirectoryDifferenceIterator *iter)
    {
        // bit slow
        MemoryBuffer flags;
        ForEach(*iter)
            flags.append((byte)iter->getFlags());
        if (flags.length()) {
            byte b = 2;
            mb.append(b).append((unsigned)flags.length()).append(flags);
        }
        serialize(mb,iter,0,true);
    }

    void serialize(MemoryBuffer &mb,bool isdiff)
    {
        byte b;
        if (isdiff&&numflags&&flags) {
            b = 2;
            mb.append(b).append(numflags).append(numflags,flags);
        }
        serialize(mb,this,0,true);
    }

};

class CCritTable;
class CEndpointCS : public CriticalSection, public CInterface
{
    CCritTable &table;
    const SocketEndpoint ep;
public:
    CEndpointCS(CCritTable &_table, const SocketEndpoint &_ep) : table(_table), ep(_ep) { }
    const void *queryFindParam() const { return &ep; }

    virtual void beforeDispose();
};

class CCritTable : private SimpleHashTableOf<CEndpointCS, const SocketEndpoint>
{
    typedef SimpleHashTableOf<CEndpointCS, const SocketEndpoint> PARENT;
    CriticalSection crit;
public:
    CEndpointCS *getCrit(const SocketEndpoint &ep)
    {
        CriticalBlock b(crit);
        Linked<CEndpointCS> clientCrit = find(ep);
        if (!clientCrit || !clientCrit->isAlive()) // if !isAlive(), then it is in the process of being destroyed/removed.
        {
            clientCrit.setown(new CEndpointCS(*this, ep));
            replace(*clientCrit); // NB table doesn't own
        }
        return clientCrit.getClear();
    }
    unsigned getHashFromElement(const void *e) const
    {
        const CEndpointCS &elem=*(const CEndpointCS *)e;
        return getHashFromFindParam(elem.queryFindParam());
    }

    unsigned getHashFromFindParam(const void *fp) const
    {
        return ((const SocketEndpoint *)fp)->hash(0);
    }

    void removeExact(CEndpointCS *clientCrit)
    {
        CriticalBlock b(crit);
        PARENT::removeExact(clientCrit); // NB may not exist, could have been replaced if detected !isAlive() in getCrit()
    }
} *dirCSTable;

MODULE_INIT(INIT_PRIORITY_STANDARD)
{
    dirCSTable = new CCritTable;
    return true;
}
MODULE_EXIT()
{
    delete dirCSTable;
}

void CEndpointCS::beforeDispose()
{
    table.removeExact(this);
}

class CRemoteFilteredFileIOBase : public CRemoteBase, implements IRemoteFileIO
{
public:
    IMPLEMENT_IINTERFACE;
    // Really a stream, but life (maybe) easier elsewhere if looks like a file
    // Sometime should refactor to be based on ISerialStream instead - or maybe IRowStream.
    CRemoteFilteredFileIOBase(SocketEndpoint &ep, const char *filename, IOutputMetaData *actual, IOutputMetaData *projected, const RowFilter &fieldFilters, unsigned __int64 chooseN)
        : CRemoteBase(ep, filename)
    {
        // NB: inputGrouped == outputGrouped for now, but may want output to be ungrouped

        openRequest();
        if (queryOutputCompressionDefault())
        {
            expander.setown(getExpander(queryOutputCompressionDefault()));
            if (expander)
            {
                expandMb.setEndian(__BIG_ENDIAN);
                request.appendf("\"outputCompression\" : \"%s\",\n", queryOutputCompressionDefault());
            }
            else
                WARNLOG("Failed to created compression decompressor for: %s", queryOutputCompressionDefault());
        }

        request.appendf("\"format\" : \"binary\",\n"
            "\"node\" : {\n"
            " \"fileName\" : \"%s\"", filename);
        if (chooseN)
            request.appendf(",\n \"chooseN\" : \"%" I64F "u\"", chooseN);
        if (fieldFilters.numFilterFields())
        {
            request.append(",\n \"keyFilter\" : [\n  ");
            for (unsigned idx=0; idx < fieldFilters.numFilterFields(); idx++)
            {
                auto &filter = fieldFilters.queryFilter(idx);
                StringBuffer filterString;
                filter.serialize(filterString);
                if (idx)
                    request.append(",\n  ");
                request.append("\"");
                encodeJSON(request, filterString.length(), filterString.str());
                request.append("\"");
            }
            request.append("\n ]");
        }
        MemoryBuffer actualTypeInfo;
        if (!dumpTypeInfo(actualTypeInfo, actual->querySerializedDiskMeta()->queryTypeInfo()))
            throw createDafsException(DAFSERR_cmdstream_unsupported_recfmt, "Format not supported by remote read");
        request.append(",\n \"inputBin\" : \"");
        JBASE64_Encode(actualTypeInfo.toByteArray(), actualTypeInfo.length(), request, false);
        request.append("\"");
        if (actual != projected)
        {
            MemoryBuffer projectedTypeInfo;
            dumpTypeInfo(projectedTypeInfo, projected->querySerializedDiskMeta()->queryTypeInfo());
            if (actualTypeInfo.length() != projectedTypeInfo.length() ||
                memcmp(actualTypeInfo.toByteArray(), projectedTypeInfo.toByteArray(), actualTypeInfo.length()))
            {
                request.append(",\n \"outputBin\": \"");
                JBASE64_Encode(projectedTypeInfo.toByteArray(), projectedTypeInfo.length(), request, false);
                request.append("\"");
            }
        }
        bufPos = 0;
    }
    virtual size32_t read(offset_t pos, size32_t len, void * data) override
    {
        assertex(pos == bufPos);  // Must read sequentially
        if (!bufRemaining && !eof)
            refill();
        if (eof)
            return 0;
        if (len > bufRemaining)
            len = bufRemaining;
        bufPos += len;
        bufRemaining -= len;
        memcpy(data, reply.readDirect(len), len);
        return len;
    }
    virtual offset_t size() override { return -1; }
    virtual size32_t write(offset_t pos, size32_t len, const void * data) override { throwUnexpected(); }
    virtual offset_t appendFile(IFile *file,offset_t pos=0,offset_t len=(offset_t)-1) override { throwUnexpected(); }
    virtual void setSize(offset_t size) override { throwUnexpected(); }
    virtual void flush() override { throwUnexpected(); }
    virtual void close() override
    {
        if (handle)
        {
            try
            {
                MemoryBuffer sendBuffer;
                initSendBuffer(sendBuffer);
                sendBuffer.append((RemoteFileCommandType)RFCcloseIO).append(handle);
                sendRemoteCommand(sendBuffer,false);
            }
            catch (IDAFS_Exception *e)
            {
                if ((e->errorCode()!=RFSERR_InvalidFileIOHandle)&&(e->errorCode()!=RFSERR_NullFileIOHandle))
                    throw;
                e->Release();
            }
            handle = 0;
        }
    }
    virtual unsigned __int64 getStatistic(StatisticKind kind) override
    {
        /* NB: Would need new stat. categories added for this to make sense,
         * but this class is implemented as a IFileIO for convenience for now,
         * it may be refactored into another form later.
         */
        return 0;
    }
// IRemoteFileIO
    virtual void addVirtualFieldMapping(const char *fieldName, const char *fieldValue) override
    {
        virtualFields[fieldName] = fieldValue;
    }
    virtual void ensureAvailable() override
    {
        if (firstRequest)
            handleFirstRequest();
    }
protected:
    StringBuffer &openRequest()
    {
        return request.append("{\n");
    }
    StringBuffer &closeRequest()
    {
        return request.append("\n }\n");
    }
    void addVirtualFields()
    {
        request.append(", \n \"virtualFields\" : {\n");
        bool first=true;
        for (auto &e : virtualFields)
        {
            if (!first)
                request.append(",\n");
            request.appendf("  \"%s\" : \"%s\"", e.first.c_str(), e.second.c_str());
            first = false;
        }
        request.append(" }");
    }
    void handleFirstRequest()
    {
        firstRequest = false;
        addVirtualFields();
        closeRequest();
        sendRequest(0, nullptr);
    }
    void refill()
    {
        if (firstRequest)
        {
            handleFirstRequest();
            return;
        }
        size32_t cursorLength;
        reply.read(cursorLength);
        if (!cursorLength)
        {
            eof = true;
            return;
        }
        MemoryBuffer mrequest;
        MemoryBuffer newReply;
        initSendBuffer(mrequest);
        mrequest.append((RemoteFileCommandType)RFCStreamRead);
        VStringBuffer json("{ \"handle\" : %u }", handle);
        mrequest.append(json.length(), json.str());
        sendRemoteCommand(mrequest, newReply);
        unsigned newHandle;
        newReply.read(newHandle);
        if (newHandle == handle)
        {
            reply.swapWith(newReply);
            reply.read(bufRemaining);
            eof = (bufRemaining == 0);
            if (expander)
            {
                size32_t expandedSz = expander->init(reply.bytes()+reply.getPos());
                expandMb.clear().reserve(expandedSz);
                expander->expand(expandMb.bufferBase());
                expandMb.swapWith(reply);
            }
        }
        else
        {
            assertex(newHandle == 0);
            sendRequest(cursorLength, reply.readDirect(cursorLength));
        }
    }
    void sendRequest(unsigned cursorLen, const void *cursorData)
    {
        MemoryBuffer mrequest;
        initSendBuffer(mrequest);
        mrequest.append((RemoteFileCommandType)RFCStreamRead);
        mrequest.append(request.length(), request.str());
        if (cursorLen)
        {
            StringBuffer cursorInfo;
            cursorInfo.append(",\"cursorBin\": \"");
            JBASE64_Encode(cursorData, cursorLen, cursorInfo, false);
            cursorInfo.append("\"\n");
            mrequest.append(cursorInfo.length(), cursorInfo.str());
        }
        if (TF_TRACE_FULL)
            PROGLOG("req = <%s}>", request.str());
        mrequest.append(3, " \n}");
        sendRemoteCommand(mrequest, reply);
        reply.read(handle);
        reply.read(bufRemaining);
        eof = (bufRemaining == 0);
        if (expander)
        {
            size32_t expandedSz = expander->init(reply.bytes()+reply.getPos());
            expandMb.clear().reserve(expandedSz);
            expander->expand(expandMb.bufferBase());
            expandMb.swapWith(reply);
        }
    }
    StringBuffer request;
    MemoryBuffer reply;
    unsigned handle = 0;
    size32_t bufRemaining = 0;
    offset_t bufPos = 0;
    bool eof = false;

    bool firstRequest = true;
    std::unordered_map<std::string, std::string> virtualFields;
    Owned<IExpander> expander;
    MemoryBuffer expandMb;
};

class CRemoteFilteredFileIO : public CRemoteFilteredFileIOBase
{
public:
    // Really a stream, but life (maybe) easier elsewhere if looks like a file
    // Sometime should refactor to be based on ISerialStream instead - or maybe IRowStream.
    CRemoteFilteredFileIO(SocketEndpoint &ep, const char *filename, IOutputMetaData *actual, IOutputMetaData *projected, const RowFilter &fieldFilters, bool compressed, bool grouped, unsigned __int64 chooseN)
        : CRemoteFilteredFileIOBase(ep, filename, actual, projected, fieldFilters, chooseN)
    {
        // NB: inputGrouped == outputGrouped for now, but may want output to be ungrouped
        request.appendf(",\n \"kind\" : \"diskread\",\n"
            " \"compressed\" : \"%s\",\n"
            " \"inputGrouped\" : \"%s\",\n"
            " \"outputGrouped\" : \"%s\"", boolToStr(compressed), boolToStr(grouped), boolToStr(grouped));
    }
};

class CRemoteFilteredRowStream : public CRemoteFilteredFileIO, implements IRowStream
{
public:
    CRemoteFilteredRowStream(const RtlRecord &_recInfo, SocketEndpoint &ep, const char * filename, IOutputMetaData *actual, IOutputMetaData *projected, const RowFilter &fieldFilters, bool compressed, bool grouped)
        : CRemoteFilteredFileIO(ep, filename, actual, projected, fieldFilters, compressed, grouped, 0), recInfo(_recInfo)
    {
    }
    virtual const byte *queryNextRow()  // NOTE - rows returned must NOT be freed
    {
        if (!bufRemaining && !eof)
            refill();
        if (eof)
            return nullptr;
        unsigned len = recInfo.getRecordSize(reply.readDirect(0));
        bufPos += len;
        bufRemaining -= len;
        return reply.readDirect(len);
    }
    virtual void stop() override
    {
        close();
        eof = true;
    }
protected:
    const RtlRecord &recInfo;
};

static StringAttr remoteOutputCompressionDefault;
void setRemoteOutputCompressionDefault(const char *type)
{
    if (!isEmptyString(type))
        remoteOutputCompressionDefault.set(type);
}
const char *queryOutputCompressionDefault() { return remoteOutputCompressionDefault; }

extern IRemoteFileIO *createRemoteFilteredFile(SocketEndpoint &ep, const char * filename, IOutputMetaData *actual, IOutputMetaData *projected, const RowFilter &fieldFilters, bool compressed, bool grouped, unsigned __int64 chooseN)
{
    try
    {
        return new CRemoteFilteredFileIO(ep, filename, actual, projected, fieldFilters, compressed, grouped, chooseN);
    }
    catch (IException *e)
    {
        EXCLOG(e, nullptr);
        e->Release();
    }
    return nullptr;
}

class CRemoteFilteredKeyIO : public CRemoteFilteredFileIOBase
{
public:
    // Really a stream, but life (maybe) easier elsewhere if looks like a file
    // Sometime should refactor to be based on ISerialStream instead - or maybe IRowStream.
    CRemoteFilteredKeyIO(SocketEndpoint &ep, const char *filename, unsigned crc, IOutputMetaData *actual, IOutputMetaData *projected, const RowFilter &fieldFilters, unsigned __int64 chooseN)
        : CRemoteFilteredFileIOBase(ep, filename, actual, projected, fieldFilters, chooseN)
    {
        request.appendf(",\n \"kind\" : \"indexread\"");
        request.appendf(",\n \"crc\" : \"%u\"", crc);
    }
};

class CRemoteFilteredKeyCountIO : public CRemoteFilteredFileIOBase
{
public:
    // Really a stream, but life (maybe) easier elsewhere if looks like a file
    // Sometime should refactor to be based on ISerialStream instead - or maybe IRowStream.
    CRemoteFilteredKeyCountIO(SocketEndpoint &ep, const char *filename, unsigned crc, IOutputMetaData *actual, const RowFilter &fieldFilters, unsigned __int64 rowLimit)
        : CRemoteFilteredFileIOBase(ep, filename, actual, actual, fieldFilters, rowLimit)
    {
        request.appendf(",\n \"kind\" : \"indexcount\"");
        request.appendf(",\n \"crc\" : \"%u\"", crc);
    }
};

class CRemoteKey : public CSimpleInterfaceOf<IIndexLookup>
{
    Owned<IRemoteFileIO> iRemoteFileIO;
    offset_t pos = 0;
    Owned<ISourceRowPrefetcher> prefetcher;
    CThorContiguousRowBuffer prefetchBuffer;
    Owned<ISerialStream> strm;
    bool pending = false;
    SocketEndpoint ep;
    StringAttr filename;
    unsigned crc;
    Linked<IOutputMetaData> actual, projected;
    RowFilter fieldFilters;

public:
    CRemoteKey(SocketEndpoint &_ep, const char *_filename, unsigned _crc, IOutputMetaData *_actual, IOutputMetaData *_projected, const RowFilter &_fieldFilters, unsigned __int64 rowLimit)
        : ep(_ep), filename(_filename), crc(_crc), actual(_actual), projected(_projected)
    {
        for (unsigned f=0; f<_fieldFilters.numFilterFields(); f++)
            fieldFilters.addFilter(OLINK(_fieldFilters.queryFilter(f)));
        iRemoteFileIO.setown(new CRemoteFilteredKeyIO(ep, filename, crc, actual, projected, fieldFilters, rowLimit));
        if (!iRemoteFileIO)
            throwStringExceptionV(DAFSERR_cmdstream_openfailure, "Unable to open remote key part: '%s'", filename.get());
        strm.setown(createFileSerialStream(iRemoteFileIO));
        prefetcher.setown(projected->createDiskPrefetcher());
        assertex(prefetcher);
        prefetchBuffer.setStream(strm);
    }
// IIndexLookup
    virtual void ensureAvailable() override
    {
        iRemoteFileIO->ensureAvailable(); // will throw an exception if fails
    }
    virtual unsigned __int64 getCount() override
    {
        return checkCount(0);
    }
    virtual unsigned __int64 checkCount(unsigned __int64 limit) override
    {
        Owned<IFileIO> iFileIO = new CRemoteFilteredKeyCountIO(ep, filename, crc, actual, fieldFilters, limit);
        unsigned __int64 result;
        iFileIO->read(0, sizeof(result), &result);
        return result;
    }
    virtual const void *nextKey() override
    {
        if (pending)
            prefetchBuffer.finishedRow();
        if (prefetchBuffer.eos())
            return nullptr;
        prefetcher->readAhead(prefetchBuffer);
        pending = true;
        return prefetchBuffer.queryRow();
    }
    virtual unsigned querySeeks() const override { return 0; } // not sure how best to handle these, perhaps should log/record somewhere on server-side
    virtual unsigned queryScans() const override { return 0; }
    virtual unsigned querySkips() const override { return 0; }
};


extern IIndexLookup *createRemoteFilteredKey(SocketEndpoint &ep, const char * filename, unsigned crc, IOutputMetaData *actual, IOutputMetaData *projected, const RowFilter &fieldFilters, unsigned __int64 chooseN)
{
    try
    {
        return new CRemoteKey(ep, filename, crc, actual, projected, fieldFilters, chooseN);
    }
    catch (IException *e)
    {
        EXCLOG(e, nullptr);
        e->Release();
    }
    return nullptr;
}


class CRemoteFile : public CRemoteBase, implements IFile
{
    StringAttr remotefilename;
    unsigned flags;
    bool isShareSet;
public:
    IMPLEMENT_IINTERFACE
    CRemoteFile(const SocketEndpoint &_ep, const char * _filename)
        : CRemoteBase(_ep, _filename)
    {
        flags = ((unsigned)IFSHread)|((S_IRUSR|S_IWUSR|S_IRGRP|S_IWGRP|S_IROTH|S_IWOTH)<<16);
        isShareSet = false;
        if (filename.length()>2 && isPathSepChar(filename[0]) && isShareChar(filename[2]))
        {
            VStringBuffer winDriveFilename("%c:%s", filename[1], filename+3);
            filename.set(winDriveFilename);
        }
    }

    bool exists()
    {
        MemoryBuffer sendBuffer;
        initSendBuffer(sendBuffer);
        MemoryBuffer replyBuffer;
        sendBuffer.append((RemoteFileCommandType)RFCexists).append(filename);
        sendRemoteCommand(sendBuffer, replyBuffer);

        bool ok;
        replyBuffer.read(ok);
        return ok;
    }

    bool getTime(CDateTime * createTime, CDateTime * modifiedTime, CDateTime * accessedTime)
    {
        CDateTime dummyTime;
        if (!createTime)
            createTime = &dummyTime;
        if (!modifiedTime)
            modifiedTime = &dummyTime;
        if (!accessedTime)
            accessedTime = &dummyTime;
        MemoryBuffer sendBuffer;
        initSendBuffer(sendBuffer);
        MemoryBuffer replyBuffer;
        sendBuffer.append((RemoteFileCommandType)RFCgettime).append(filename);
        sendRemoteCommand(sendBuffer, replyBuffer);

        bool ok;
        replyBuffer.read(ok);
        if (ok) {
            createTime->deserialize(replyBuffer);
            modifiedTime->deserialize(replyBuffer);
            accessedTime->deserialize(replyBuffer);
        }
        return ok;
    }

    bool setTime(const CDateTime * createTime, const CDateTime * modifiedTime, const CDateTime * accessedTime)
    {
        MemoryBuffer sendBuffer;
        initSendBuffer(sendBuffer);
        MemoryBuffer replyBuffer;
        sendBuffer.append((RemoteFileCommandType)RFCsettime).append(filename);
        if (createTime)
        {
            sendBuffer.append((bool)true);
            createTime->serialize(sendBuffer);
        }
        else
            sendBuffer.append((bool)false);
        if (modifiedTime)
        {
            sendBuffer.append((bool)true);
            modifiedTime->serialize(sendBuffer);
        }
        else
            sendBuffer.append((bool)false);
        if (accessedTime)
        {
            sendBuffer.append((bool)true);
            accessedTime->serialize(sendBuffer);
        }
        else
            sendBuffer.append((bool)false);
        sendRemoteCommand(sendBuffer, replyBuffer);

        bool ok;
        replyBuffer.read(ok);
        return ok;
    }

    fileBool isDirectory()
    {
        MemoryBuffer sendBuffer;
        initSendBuffer(sendBuffer);
        MemoryBuffer replyBuffer;
        sendBuffer.append((RemoteFileCommandType)RFCisdirectory).append(filename);
        sendRemoteCommand(sendBuffer, replyBuffer);

        unsigned ret;
        replyBuffer.read(ret);
        return (fileBool)ret;
    }


    fileBool isFile()
    {
        MemoryBuffer sendBuffer;
        initSendBuffer(sendBuffer);
        MemoryBuffer replyBuffer;
        sendBuffer.append((RemoteFileCommandType)RFCisfile).append(filename);
        sendRemoteCommand(sendBuffer, replyBuffer);

        unsigned ret;
        replyBuffer.read(ret);
        return (fileBool)ret;
    }

    fileBool isReadOnly()
    {
        MemoryBuffer sendBuffer;
        initSendBuffer(sendBuffer);
        MemoryBuffer replyBuffer;
        sendBuffer.append((RemoteFileCommandType)RFCisreadonly).append(filename);
        sendRemoteCommand(sendBuffer, replyBuffer);

        unsigned ret;
        replyBuffer.read(ret);
        return (fileBool)ret;
    }

    IFileIO * open(IFOmode mode,IFEflags extraFlags=IFEnone);
    IFileIO * openShared(IFOmode mode,IFSHmode shmode,IFEflags extraFlags=IFEnone);
    IFileAsyncIO * openAsync(IFOmode mode) { return NULL; } // not supported

    const char * queryFilename()
    {
        if (remotefilename.isEmpty()) {
            RemoteFilename rfn;
            rfn.setPath(ep,filename);
            StringBuffer path;
            rfn.getRemotePath(path);
            remotefilename.set(path);
        }
        return remotefilename.get();
    }

    void resetLocalFilename(const char *name)
    {
        remotefilename.clear();
        filename.set(name);
    }

    bool remove()
    {
        MemoryBuffer sendBuffer;
        initSendBuffer(sendBuffer);
        MemoryBuffer replyBuffer;
        sendBuffer.append((RemoteFileCommandType)RFCremove).append(filename);
        sendRemoteCommand(sendBuffer, replyBuffer);

        bool ok;
        replyBuffer.read(ok);
        return ok;
    }

    void rename(const char *newname)
    {
    // currently ignores directory on newname (in future versions newname will be required to be tail only and not full path)
        StringBuffer path;
        splitDirTail(filename,path);
        StringBuffer newdir;
        path.append(splitDirTail(newname,newdir));
        if (newdir.length()&&(strcmp(newdir.str(),path.str())!=0))
            WARNLOG("CRemoteFile::rename passed full path '%s' that may not to match original directory '%s'",newname,path.str());
        MemoryBuffer sendBuffer;
        initSendBuffer(sendBuffer);
        MemoryBuffer replyBuffer;
        sendBuffer.append((RemoteFileCommandType)RFCrename).append(filename).append(path);
        sendRemoteCommand(sendBuffer, replyBuffer);
        filename.set(path);
        remotefilename.clear();
    }

    void move(const char *newname)
    {
        // like rename except between directories
        // first create replote path
        if (!newname||!*newname)
            return;
        RemoteFilename destrfn;
        if (isPathSepChar(newname[0])&&isPathSepChar(newname[1])) {
            destrfn.setRemotePath(newname);
            if (!destrfn.queryEndpoint().ipequals(ep)) {
                StringBuffer msg;
                msg.appendf("IFile::move %s to %s, destination node must match source node", queryFilename(), newname);
                throw createDafsException(RFSERR_MoveFailed,msg.str());
            }
        }
        else
            destrfn.setPath(ep,newname);
        StringBuffer dest;
        newname = destrfn.getLocalPath(dest).str();
        MemoryBuffer sendBuffer;
        initSendBuffer(sendBuffer);
        MemoryBuffer replyBuffer;
        StringBuffer path;
        splitDirTail(filename,path);
        StringBuffer newdir;
        const char *newtail = splitDirTail(newname,newdir);
        if (strcmp(newdir.str(),path.str())==0)
        {
            path.append(newtail);
            newname = path;
            sendBuffer.append((RemoteFileCommandType)RFCrename);    // use rename if we can (supported on older dafilesrv)
        }
        else
            sendBuffer.append((RemoteFileCommandType)RFCmove);
        sendBuffer.append(filename).append(newname);
        sendRemoteCommand(sendBuffer, replyBuffer);
        filename.set(newname);
        remotefilename.clear();
    }

    void setReadOnly(bool set)
    {
        MemoryBuffer sendBuffer;
        initSendBuffer(sendBuffer);
        MemoryBuffer replyBuffer;
        sendBuffer.append((RemoteFileCommandType)RFCsetreadonly).append(filename).append(set);
        sendRemoteCommand(sendBuffer, replyBuffer);
    }

    void setFilePermissions(unsigned fPerms)
    {
        MemoryBuffer sendBuffer;
        initSendBuffer(sendBuffer);
        MemoryBuffer replyBuffer;
        sendBuffer.append((RemoteFileCommandType)RFCsetfileperms).append(filename).append(fPerms);
        try
        {
            sendRemoteCommand(sendBuffer, replyBuffer);
        }
        catch (IDAFS_Exception *e)
        {
            if (e->errorCode() == RFSERR_InvalidCommand)
            {
                WARNLOG("umask setFilePermissions (0%o) not supported on remote server", fPerms);
                e->Release();
            }
            else
                throw;
        }

    }

    offset_t size()
    {
#if 1 // faster method (consistant with IFile)
        // do this by using dir call (could be improved with new function but this not *too* bad)
        if (isSpecialPath(filename))
            return 0;   // queries deemed to always exist (though don't know size).
                        // if needed to get size I guess could use IFileIO method and cache (bit of pain though)
        StringBuffer dir;
        const char *tail = splitDirTail(filename,dir);
        if (!dir.length())
            return false;
        MemoryBuffer sendBuffer;
        initSendBuffer(sendBuffer);
        MemoryBuffer replyBuffer;
        bool includedirs = true;
        bool sub=false;
        {
            //Could be removed with new dafilesrv change [ (stream != 0) ], since this is not streaming.
            Owned<CEndpointCS> crit = dirCSTable->getCrit(ep); // NB dirCSTable doesn't own, last reference will remove from table
            CriticalBlock block(*crit);
            sendBuffer.append((RemoteFileCommandType)RFCgetdir).append(dir).append(tail).append(includedirs).append(sub);
            try
            {
                sendRemoteCommand(sendBuffer, replyBuffer);
            }
            catch (IDAFS_Exception * e)
            {
                if (e->errorCode() == RFSERR_GetDirFailed)
                {
                    e->Release();
                    return (offset_t)-1;
                }
                else
                    throw e;
            }
        }
        // now should be 0 or 1 files returned
        Owned<CRemoteDirectoryIterator> iter = new CRemoteDirectoryIterator(ep, dir.str());
        iter->appendBuf(replyBuffer);
        if (!iter->first())
            return (offset_t)-1;
        return (offset_t) iter->getFileSize();
#else
        IFileIO * io = open(IFOread);
        offset_t length = (offset_t)-1;
        if (io)
        {
            length = io->size();
            io->Release();
        }
        return length;
#endif
    }

    bool createDirectory()
    {
        MemoryBuffer sendBuffer;
        initSendBuffer(sendBuffer);
        MemoryBuffer replyBuffer;
        sendBuffer.append((RemoteFileCommandType)RFCcreatedir).append(filename);
        sendRemoteCommand(sendBuffer, replyBuffer);

        bool ok;
        replyBuffer.read(ok);
        return ok;
    }

    virtual IDirectoryIterator *directoryFiles(const char *mask,bool sub,bool includedirs)
    {
        if (mask&&!*mask)
            return createDirectoryIterator("",""); // NULL iterator

        CRemoteDirectoryIterator *ret = new CRemoteDirectoryIterator(ep, filename);
        byte stream = (sub || !mask || containsFileWildcard(mask)) ? 1 : 0; // no point in streaming if mask without wildcards or sub, as will only be <= 1 match.

        Owned<CEndpointCS> crit = dirCSTable->getCrit(ep); // NB dirCSTable doesn't own, last reference will remove from table
        CriticalBlock block(*crit);
        for (;;)
        {
            MemoryBuffer sendBuffer;
            initSendBuffer(sendBuffer);
            MemoryBuffer replyBuffer;
            sendBuffer.append((RemoteFileCommandType)RFCgetdir).append(filename).append(mask?mask:"").append(includedirs).append(sub).append(stream);
            sendRemoteCommand(sendBuffer, replyBuffer);
            if (ret->appendBuf(replyBuffer))
                break;
            stream = 2; // NB: will never get here if streaming was off (if stream==0 above)
        }
        return ret;
    }

    IDirectoryDifferenceIterator *monitorDirectory(
                                  IDirectoryIterator *prev=NULL,    // in (NULL means use current as baseline)
                                  const char *mask=NULL,
                                  bool sub=false,
                                  bool includedirs=false,
                                  unsigned checkinterval=60*1000,
                                  unsigned timeout=(unsigned)-1,
                                  Semaphore *abortsem=NULL) // returns NULL if timed out
    {
        // abortsem not yet supported
        MemoryBuffer sendBuffer;
        initSendBuffer(sendBuffer);
        MemoryBuffer replyBuffer;
        sendBuffer.append((RemoteFileCommandType)RFCmonitordir).append(filename).append(mask?mask:"").append(includedirs).append(sub);
        sendBuffer.append(checkinterval).append(timeout);
        __int64 cancelid=0; // not yet used
        sendBuffer.append(cancelid);
        byte isprev=(prev!=NULL)?1:0;
        sendBuffer.append(isprev);
        if (prev)
            CRemoteDirectoryIterator::serialize(sendBuffer,prev,0,true);
        sendRemoteCommand(sendBuffer, replyBuffer);
        byte status;
        replyBuffer.read(status);
        if (status==1)
        {
            CRemoteDirectoryIterator *iter = new CRemoteDirectoryIterator(ep, filename);
            iter->appendBuf(replyBuffer);
            return iter;
        }
        return NULL;
    }

    bool getInfo(bool &isdir,offset_t &size,CDateTime &modtime)
    {
        // do this by using dir call (could be improved with new function but this not *too* bad)
        StringBuffer dir;
        const char *tail = splitDirTail(filename,dir);
        if (!dir.length())
            return false;
        MemoryBuffer sendBuffer;
        initSendBuffer(sendBuffer);
        MemoryBuffer replyBuffer;
        bool includedirs = true;
        bool sub=false;
        {
            //Could be removed with new dafilesrv change [ (stream != 0) ], since this is not streaming.
            Owned<CEndpointCS> crit = dirCSTable->getCrit(ep); // NB dirCSTable doesn't own, last reference will remove from table
            CriticalBlock block(*crit);
            sendBuffer.append((RemoteFileCommandType)RFCgetdir).append(dir).append(tail).append(includedirs).append(sub);
            sendRemoteCommand(sendBuffer, replyBuffer);
        }
        // now should be 0 or 1 files returned
        Owned<CRemoteDirectoryIterator> iter = new CRemoteDirectoryIterator(ep, dir.str());
        iter->appendBuf(replyBuffer);
        if (!iter->first())
            return false;
        isdir = iter->isDir();
        size = (offset_t) iter->getFileSize();
        iter->getModifiedTime(modtime);
        return true;
    }



    bool setCompression(bool set)
    {
        assertex(!"Need to implement compress()");
        return false;
    }

    offset_t compressedSize()
    {
        assertex(!"Need to implement actualSize()");
        return (offset_t)-1;
    }

    void serialize(MemoryBuffer &tgt)
    {
        throwUnexpected();
    }

    void deserialize(MemoryBuffer &src)
    {
        throwUnexpected();
    }

    unsigned getCRC()
    {
        MemoryBuffer sendBuffer;
        initSendBuffer(sendBuffer);
        MemoryBuffer replyBuffer;
        sendBuffer.append((RemoteFileCommandType)RFCgetcrc).append(filename);
        sendRemoteCommand(sendBuffer, replyBuffer, true, true);

        unsigned crc;
        replyBuffer.read(crc);
        return crc;
    }

    void setCreateFlags(unsigned short cflags)
    {
        flags &= 0xffff;
        flags |= ((unsigned)cflags<<16);
    }

    unsigned short getCreateFlags()
    {
        return (unsigned short)(flags>>16);
    }

    void setShareMode(IFSHmode shmode)
    {
        flags &= ~(IFSHfull|IFSHread);
        flags |= (unsigned)(shmode&(IFSHfull|IFSHread));
        isShareSet = true;
    }

    unsigned short getShareMode()
    {
        return (unsigned short)(flags&0xffff);
    }

    bool getIsShareSet()
    {
        return isShareSet;
    }

    void remoteExtractBlobElements(const char * prefix, ExtractedBlobArray & extracted)
    {
        MemoryBuffer sendBuffer;
        initSendBuffer(sendBuffer);
        sendBuffer.append((RemoteFileCommandType)RFCextractblobelements).append(prefix).append(filename);
        MemoryBuffer replyBuffer;
        sendRemoteCommand(sendBuffer, replyBuffer, true, true); // handles error code
        unsigned n;
        replyBuffer.read(n);
        for (unsigned i=0;i<n;i++) {
            ExtractedBlobInfo *item = new ExtractedBlobInfo;
            item->deserialize(replyBuffer);
            extracted.append(*item);
        }
    }

    bool copySectionAsync(const char *uuid,const RemoteFilename &dest, offset_t toOfs, offset_t fromOfs, offset_t size, ICopyFileProgress *progress, unsigned timeout)
    {
        // now if we get here is it can be assumed the source file is local to where we send the command
        StringBuffer tos;
        dest.getRemotePath(tos);
        MemoryBuffer sendBuffer;
        initSendBuffer(sendBuffer);
        MemoryBuffer replyBuffer;
        sendBuffer.append((RemoteFileCommandType)RFCcopysection).append(uuid).append(queryLocalName()).append(tos).append(toOfs).append(fromOfs).append(size).append(timeout);
        sendRemoteCommand(sendBuffer, replyBuffer);
        unsigned status;
        replyBuffer.read(status);
        if (progress)
        {
            offset_t sizeDone;
            offset_t totalSize;
            replyBuffer.read(sizeDone).read(totalSize);
            progress->onProgress(sizeDone,totalSize);
        }
        return (AsyncCommandStatus)status!=ACScontinue; // should only otherwise be done as errors raised by exception
    }

    void copySection(const RemoteFilename &dest, offset_t toOfs, offset_t fromOfs, offset_t size, ICopyFileProgress *progress, CFflags copyFlags=CFnone)
    {
        StringBuffer uuid;
        genUUID(uuid,true);
        unsigned timeout = 60*1000; // check every minute
        while(!copySectionAsync(uuid.str(),dest,toOfs,fromOfs,size,progress,timeout));
    }

    void copyTo(IFile *dest, size32_t buffersize, ICopyFileProgress *progress, bool usetmp, CFflags copyFlags=CFnone);

    virtual IMemoryMappedFile *openMemoryMapped(offset_t ofs, memsize_t len, bool write)
    {
        return NULL;
    }
};

void clientAddSocketToCache(SocketEndpoint &ep,ISocket *socket)
{
    CriticalBlock block(CConnectionTable::crit);
    if (ConnectionTable)
        ConnectionTable->addLink(ep,socket);
}


IFile * createRemoteFile(SocketEndpoint &ep, const char * filename)
{
    IFile *ret = createFileLocalMount(ep,filename);
    if (ret)
        return ret;
    return new CRemoteFile(ep, filename);
}


void clientDisconnectRemoteFile(IFile *file)
{
    CRemoteFile *cfile = QUERYINTERFACE(file,CRemoteFile);
    if (cfile)
        cfile->disconnect();
}

bool clientResetFilename(IFile *file, const char *newname) // returns false if not remote
{
    CRemoteFile *cfile = QUERYINTERFACE(file,CRemoteFile);
    if (!cfile)
        return false;
    cfile->resetLocalFilename(newname);
    return true;
}



extern bool clientAsyncCopyFileSection(const char *uuid,
                        IFile *from,                        // expected to be remote
                        RemoteFilename &to,
                        offset_t toOfs,                     // -1 created file and copies to start
                        offset_t fromOfs,
                        offset_t size,
                        ICopyFileProgress *progress,
                        unsigned timeout)       // returns true when done
{
    CRemoteFile *cfile = QUERYINTERFACE(from,CRemoteFile);
    if (!cfile) {
        // local - do sync
        from->copySection(to,toOfs,fromOfs,size,progress);
        return true;
    }
    return cfile->copySectionAsync(uuid,to,toOfs,fromOfs, size, progress, timeout);

}




//---------------------------------------------------------------------------

class CRemoteFileIO : implements IFileIO, public CInterface
{
protected:
    Linked<CRemoteFile> parent;
    RemoteFileIOHandle  handle;
    std::atomic<cycle_t> ioReadCycles;
    std::atomic<cycle_t> ioWriteCycles;
    std::atomic<__uint64> ioReadBytes;
    std::atomic<__uint64> ioWriteBytes;
    std::atomic<__uint64> ioReads;
    std::atomic<__uint64> ioWrites;
    std::atomic<unsigned> ioRetries;
    IFOmode mode;
    compatIFSHmode compatmode;
    IFEflags extraFlags;
    bool disconnectonexit;
public:
    IMPLEMENT_IINTERFACE
    CRemoteFileIO(CRemoteFile *_parent)
        : parent(_parent), ioReadCycles(0), ioWriteCycles(0), ioReadBytes(0), ioWriteBytes(0), ioReads(0), ioWrites(0), ioRetries(0)
    {
        handle = 0;
        disconnectonexit = false;
    }

    ~CRemoteFileIO()
    {
        if (handle) {
            try {
                close();
            }
            catch (IException *e) {
                StringBuffer s;
                e->errorMessage(s);
                WARNLOG("CRemoteFileIO close file: %s",s.str());
                e->Release();
            }
        }
        if (disconnectonexit)
            parent->disconnect();
    }

    void close()
    {
        if (handle)
        {
            try
            {
                MemoryBuffer sendBuffer;
                initSendBuffer(sendBuffer);
                sendBuffer.append((RemoteFileCommandType)RFCcloseIO).append(handle);
                parent->sendRemoteCommand(sendBuffer,false);
            }
            catch (IDAFS_Exception *e)
            {
                if ((e->errorCode()!=RFSERR_InvalidFileIOHandle)&&(e->errorCode()!=RFSERR_NullFileIOHandle))
                    throw;
                e->Release();
            }
            handle = 0;
        }
    }
    RemoteFileIOHandle getHandle() const { return handle; }
    bool open(IFOmode _mode,compatIFSHmode _compatmode,IFEflags _extraFlags=IFEnone)
    {
        MemoryBuffer sendBuffer;
        initSendBuffer(sendBuffer);
        MemoryBuffer replyBuffer;
        const char *localname = parent->queryLocalName();
        localname = skipSpecialPath(localname);
        // also send _extraFlags
        // then also send sMode, cFlags
        unsigned short sMode = parent->getShareMode();
        unsigned short cFlags = parent->getCreateFlags();
        if (!(parent->getIsShareSet()))
        {
            switch ((compatIFSHmode)_compatmode)
            {
                case compatIFSHnone:
                    sMode = IFSHnone;
                    break;
                case compatIFSHread:
                    sMode = IFSHread;
                    break;
                case compatIFSHwrite:
                    sMode = IFSHfull;
                    break;
                case compatIFSHall:
                    sMode = IFSHfull;
                    break;
            }
        }
        sendBuffer.append((RemoteFileCommandType)RFCopenIO).append(localname).append((byte)_mode).append((byte)_compatmode).append((byte)_extraFlags).append(sMode).append(cFlags);
        parent->sendRemoteCommand(sendBuffer, replyBuffer);

        replyBuffer.read(handle);
        if (!handle)
            return false;
        switch (_mode) {
        case IFOcreate:
            mode = IFOwrite;
            break;
        case IFOcreaterw:
            mode = IFOreadwrite;
            break;
        default:
            mode = _mode;
            break;
        }
        compatmode = _compatmode;
        extraFlags = _extraFlags;
        return true;
    }

    bool reopen()
    {
        StringBuffer s;
        PROGLOG("Attempting reopen of %s on %s",parent->queryLocalName(),parent->queryEp().getUrlStr(s).str());
        if (open(mode,compatmode,extraFlags))
            return true;
        return false;

    }


    offset_t size()
    {
        MemoryBuffer sendBuffer;
        initSendBuffer(sendBuffer);
        MemoryBuffer replyBuffer;
        sendBuffer.append((RemoteFileCommandType)RFCsize).append(handle);
        parent->sendRemoteCommand(sendBuffer, replyBuffer, false);
        // Retry using reopen TBD

        offset_t ret;
        replyBuffer.read(ret);
        return ret;
    }

    virtual unsigned __int64 getStatistic(StatisticKind kind)
    {
        switch (kind)
        {
        case StCycleDiskReadIOCycles:
            return ioReadCycles.load(std::memory_order_relaxed);
        case StCycleDiskWriteIOCycles:
            return ioWriteCycles.load(std::memory_order_relaxed);
        case StTimeDiskReadIO:
            return cycle_to_nanosec(ioReadCycles.load(std::memory_order_relaxed));
        case StTimeDiskWriteIO:
            return cycle_to_nanosec(ioWriteCycles.load(std::memory_order_relaxed));
        case StSizeDiskRead:
            return ioReadBytes.load(std::memory_order_relaxed);
        case StSizeDiskWrite:
            return ioWriteBytes.load(std::memory_order_relaxed);
        case StNumDiskReads:
            return ioReads.load(std::memory_order_relaxed);
        case StNumDiskWrites:
            return ioWrites.load(std::memory_order_relaxed);
        case StNumDiskRetries:
            return ioRetries.load(std::memory_order_relaxed);
        }
        return 0;
    }

    size32_t read(offset_t pos, size32_t len, void * data)
    {
        size32_t got;
        MemoryBuffer replyBuffer;
        CCycleTimer timer;
        const void *b;
        try
        {
            b = doRead(pos,len,replyBuffer,got,data);
        }
        catch (...)
        {
            ioReadCycles.fetch_add(timer.elapsedCycles());
            throw;
        }
        ioReadCycles.fetch_add(timer.elapsedCycles());
        ioReadBytes.fetch_add(got);
        ++ioReads;
        if (b!=data)
            memcpy(data,b,got);
        return got;
    }

    virtual void flush()
    {
    }

    const void *doRead(offset_t pos, size32_t len, MemoryBuffer &replyBuffer, size32_t &got, void *dstbuf)
    {
        unsigned tries=0;
        for (;;)
        {
            try
            {
                MemoryBuffer sendBuffer;
                initSendBuffer(sendBuffer);
                replyBuffer.clear();
                sendBuffer.append((RemoteFileCommandType)RFCread).append(handle).append(pos).append(len);
                parent->sendRemoteCommand(sendBuffer, replyBuffer,false);
                // kludge dafilesrv versions <= 1.5e don't return error correctly 
                if (replyBuffer.length()>len+sizeof(size32_t)+sizeof(unsigned))
                {
                    size32_t save = replyBuffer.getPos();
                    replyBuffer.reset(len+sizeof(size32_t)+sizeof(unsigned));
                    unsigned errCode;
                    replyBuffer.read(errCode);
                    if (errCode)
                    {
                        StringBuffer msg;
                        parent->ep.getUrlStr(msg.append('[')).append("] ");
                        if (replyBuffer.getPos()<replyBuffer.length())
                        {
                            StringAttr s;
                            replyBuffer.read(s);
                            msg.append(s);
                        }
                        else
                            msg.append("ERROR #").append(errCode);
                        throw createDafsException(errCode, msg.str());
                    }
                    else
                        replyBuffer.reset(save);
                }
                replyBuffer.read(got);
                if ((got>replyBuffer.remaining())||(got>len))
                {
                    PROGLOG("Read beyond buffer %d,%d,%d",got,replyBuffer.remaining(),len);
                    throw createDafsException(RFSERR_ReadFailed, "Read beyond buffer");
                }
                return replyBuffer.readDirect(got);
            }
            catch (IJSOCK_Exception *e)
            {
                EXCLOG(e,"CRemoteFileIO::read");
                if (++tries > 3)
                {
                    ioRetries.fetch_add(tries);
                    throw;
                }
                WARNLOG("Retrying read of %s (%d)",parent->queryLocalName(),tries);
                Owned<IException> exc = e;
                if (!reopen())
                {
                    ioRetries.fetch_add(tries);
                    throw exc.getClear();
                }
            }
        }
        if (tries)
            ioRetries.fetch_add(tries);
        got = 0;
        return NULL;
    }


    size32_t write(offset_t pos, size32_t len, const void * data)
    {
        unsigned tries=0;
        size32_t ret = 0;
        CCycleTimer timer;
        for (;;)
        {
            try
            {
                MemoryBuffer replyBuffer;
                MemoryBuffer sendBuffer;
                initSendBuffer(sendBuffer);
                sendBuffer.append((RemoteFileCommandType)RFCwrite).append(handle).append(pos).append(len).append(len, data);
                parent->sendRemoteCommand(sendBuffer, replyBuffer, false, true);
                replyBuffer.read(ret);
                break;
            }
            catch (IJSOCK_Exception *e)
            {
                EXCLOG(e,"CRemoteFileIO::write");
                if (++tries > 3)
                {
                    ioRetries.fetch_add(tries);
                    ioWriteCycles.fetch_add(timer.elapsedCycles());
                    throw;
                }
                WARNLOG("Retrying write(%" I64F "d,%d) of %s (%d)",pos,len,parent->queryLocalName(),tries);
                Owned<IException> exc = e;
                if (!reopen())
                {
                    ioRetries.fetch_add(tries);
                    ioWriteCycles.fetch_add(timer.elapsedCycles());
                    throw exc.getClear();
                }
            }
        }

        if (tries)
            ioRetries.fetch_add(tries);

        ioWriteCycles.fetch_add(timer.elapsedCycles());
        ioWriteBytes.fetch_add(ret);
        ++ioWrites;
        if ((ret==(size32_t)-1) || (ret < len))
            throw createDafsException(DISK_FULL_EXCEPTION_CODE,"write failed, disk full?");
        return ret;
    }

    offset_t appendFile(IFile *file,offset_t pos,offset_t len)
    {
        MemoryBuffer sendBuffer;
        initSendBuffer(sendBuffer);
        MemoryBuffer replyBuffer;
        const char * fname = file->queryFilename();
        sendBuffer.append((RemoteFileCommandType)RFCappend).append(handle).append(fname).append(pos).append(len);
        parent->sendRemoteCommand(sendBuffer, replyBuffer, false, true); // retry not safe

        offset_t ret;
        replyBuffer.read(ret);

        if ((ret==(offset_t)-1) || ((len != ((offset_t)-1)) && (ret < len)))
            throw createDafsException(DISK_FULL_EXCEPTION_CODE,"append failed, disk full?");    // though could be file missing TBD
        return ret;
    }


    void setSize(offset_t size)
    {
        MemoryBuffer sendBuffer;
        initSendBuffer(sendBuffer);
        MemoryBuffer replyBuffer;
        sendBuffer.append((RemoteFileCommandType)RFCsetsize).append(handle).append(size);
        parent->sendRemoteCommand(sendBuffer, replyBuffer, false, true);
        // retry using reopen TBD


    }

    void setDisconnectOnExit(bool set) { disconnectonexit = set; }

    void sendRemoteCommand(MemoryBuffer & sendBuffer, MemoryBuffer & replyBuffer, bool retry=true, bool lengthy=false, bool handleErrCode=true)
    {
        parent->sendRemoteCommand(sendBuffer, replyBuffer, retry, lengthy, handleErrCode);
    }
};

void clientDisconnectRemoteIoOnExit(IFileIO *fileio,bool set)
{
    CRemoteFileIO *cfileio = QUERYINTERFACE(fileio,CRemoteFileIO);
    if (cfileio)
        cfileio->setDisconnectOnExit(set);
}



IFileIO * CRemoteFile::openShared(IFOmode mode,IFSHmode shmode,IFEflags extraFlags)
{
    // 0x0, 0x8, 0x10 and 0x20 are only share modes supported in this assert
    // currently only 0x0 (IFSHnone), 0x8 (IFSHread) and 0x10 (IFSHfull) are used so this could be 0xffffffe7
    // note: IFSHfull also includes read sharing (ie write|read)
    assertex(((unsigned)shmode&0xffffffc7)==0);
    compatIFSHmode compatmode;
    unsigned fileflags = (flags>>16) &  (S_IRUSR|S_IWUSR|S_IXUSR|S_IRGRP|S_IWGRP|S_IXGRP|S_IROTH|S_IWOTH|S_IXOTH);
    if (fileflags&S_IXUSR)                      // this is bit hit and miss but backward compatible
        compatmode = compatIFSHexec;
    else if (fileflags&(S_IWGRP|S_IWOTH))
        compatmode = compatIFSHall;
    else if (shmode&IFSHfull)
        compatmode = compatIFSHwrite;
    else if (((shmode&(IFSHread|IFSHfull))==0) && ((fileflags&(S_IRGRP|S_IROTH))==0))
        compatmode = compatIFSHnone;
    else
        compatmode = compatIFSHread;
    Owned<CRemoteFileIO> res = new CRemoteFileIO(this);
    if (res->open(mode,compatmode,extraFlags))
        return res.getClear();
    return NULL;
}

IFileIO * CRemoteFile::open(IFOmode mode,IFEflags extraFlags)
{
    return openShared(mode,(IFSHmode)(flags&(IFSHread|IFSHfull)),extraFlags);
}

//---------------------------------------------------------------------------

void CRemoteFile::copyTo(IFile *dest, size32_t buffersize, ICopyFileProgress *progress, bool usetmp, CFflags copyFlags)
{
    CRemoteFile *dstfile = QUERYINTERFACE(dest,CRemoteFile);
    if (dstfile&&!dstfile->queryEp().isLocal()) {
        StringBuffer tmpname;
        Owned<IFile> destf;
        RemoteFilename dest;
        if (usetmp) {
            makeTempCopyName(tmpname,dstfile->queryLocalName());
            dest.setPath(dstfile->queryEp(),tmpname.str());
        }
        else
            dest.setPath(dstfile->queryEp(),dstfile->queryLocalName());
        destf.setown(createIFile(dest));
        try {
            // following may fail if new dafilesrv not deployed on src
            copySection(dest,(offset_t)-1,0,(offset_t)-1,progress,copyFlags);
            if (usetmp) {
                StringAttr tail(pathTail(dstfile->queryLocalName()));
                dstfile->remove();
                destf->rename(tail);
            }
            return;
        }
        catch (IException *e)
        {
            StringBuffer s;
            s.appendf("Remote File Copy (%d): ",e->errorCode());
            e->errorMessage(s);
            s.append(", retrying local");
            WARNLOG("%s",s.str());
            e->Release();
        }
        // delete dest
        try {
            destf->remove();
        }
        catch (IException *e)
        {
            EXCLOG(e,"Remote File Copy, Deleting temporary file");
            e->Release();
        }
    }
    // assumption if we get here that source remote, dest local (or equiv)
    class cIntercept: implements ICopyFileIntercept
    {
        MemoryAttr ma;
        MemoryBuffer mb;
        virtual offset_t copy(IFileIO *from, IFileIO *to, offset_t ofs, size32_t sz)
        {
            if (ma.length()<sz)
                ma.allocate(sz);    // may be not used
            void *buf = ma.bufferBase();
            size32_t got;
            CRemoteFileIO *srcio = QUERYINTERFACE(from,CRemoteFileIO);
            const void *dst;
            if (srcio)
                dst = srcio->doRead(ofs,sz,mb.clear(),got,buf);
            else {
                // shouldn't ever get here if source remote
                got = from->read(ofs, sz, buf);
                dst = buf;
            }
            if (got != 0)
                to->write(ofs, got, dst);
            return got;
        }
    } intercept;
    doCopyFile(dest,this,buffersize,progress,&intercept,usetmp,copyFlags);
}

/////////////////////////

ISocket *checkSocketSecure(ISocket *socket)
{
    if (securitySettings.connectMethod == SSLNone)
        return LINK(socket);

    char pname[256];
    pname[0] = 0;
    int pport = socket->peer_name(pname, sizeof(pname)-1);

    if ( (pport == securitySettings.daFileSrvSSLPort) && (!socket->isSecure()) )
    {
#ifdef _USE_OPENSSL
        Owned<ISecureSocket> ssock;
        try
        {
            ssock.setown(createSecureSocket(LINK(socket), ClientSocket));
            int status = ssock->secure_connect();
            if (status < 0)
                throw createDafsException(DAFSERR_connection_failed, "Failure to establish secure connection");
            return ssock.getClear();
        }
        catch (IException *e)
        {
            cleanupSocket(ssock);
            ssock.clear();
            cleanupSocket(socket);
            StringBuffer eMsg;
            e->errorMessage(eMsg);
            e->Release();
            throw createDafsException(DAFSERR_connection_failed, eMsg.str());
        }
#else
        throw createDafsException(DAFSERR_connection_failed,"Failure to establish secure connection: OpenSSL disabled in build");
#endif
    }

    return LINK(socket);
}

ISocket *connectDafs(SocketEndpoint &ep, unsigned timeoutms)
{
    Owned<ISocket> socket;

    if ( (securitySettings.connectMethod == SSLNone) || (securitySettings.connectMethod == SSLOnly) )
    {
        socket.setown(ISocket::connect_timeout(ep, timeoutms));
        return checkSocketSecure(socket);
    }

    // SSLFirst or UnsecureFirst ...

    unsigned newtimeout = timeoutms;
    if (newtimeout > 5000)
        newtimeout = 5000;

    int conAttempts = 2;
    while (conAttempts > 0)
    {
        conAttempts--;
        bool connected = false;
        try
        {
            socket.setown(ISocket::connect_timeout(ep, newtimeout));
            connected = true;
            newtimeout = timeoutms;
        }
        catch (IJSOCK_Exception *e)
        {
            if (e->errorCode() == JSOCKERR_connection_failed)
            {
                e->Release();
                if (ep.port == securitySettings.daFileSrvSSLPort)
                    ep.port = securitySettings.daFileSrvPort;
                else
                    ep.port = securitySettings.daFileSrvSSLPort;
                if (!conAttempts)
                    throw;
            }
            else
                throw;
        }

        if (connected)
        {
            if (ep.port == securitySettings.daFileSrvSSLPort)
            {
                try
                {
                    return checkSocketSecure(socket);
                }
                catch (IDAFS_Exception *e)
                {
                    connected = false;
                    if (e->errorCode() == DAFSERR_connection_failed)
                    {
                        // worth logging to help identify any ssl config issues ...
                        StringBuffer errmsg;
                        e->errorMessage(errmsg);
                        WARNLOG("%s", errmsg.str());
                        e->Release();
                        ep.port = securitySettings.daFileSrvPort;
                        if (!conAttempts)
                            throw;
                    }
                    else
                        throw;
                }
            }
            else
                return socket.getClear();
        }
    }

    throw createDafsException(DAFSERR_connection_failed, "Failed to establish connection with DaFileSrv");
}

unsigned getRemoteVersion(CRemoteFileIO &remoteFileIO, StringBuffer &ver)
{
    unsigned ret;
    MemoryBuffer sendBuffer;
    initSendBuffer(sendBuffer);
    sendBuffer.append((RemoteFileCommandType)RFCgetver);
    sendBuffer.append((unsigned)RFCgetver);
    MemoryBuffer replyBuffer;
    try
    {
        remoteFileIO.sendRemoteCommand(sendBuffer, replyBuffer, true, false, false);
    }
    catch (IException *e)
    {
        EXCLOG(e);
        ::Release(e);
        return 0;
    }
    unsigned errCode;
    replyBuffer.read(errCode);
    if (errCode==RFSERR_InvalidCommand)
    {
        ver.append("DS V1.0");
        return 10;
    }
    else if (errCode==0)
        ret = 11;
    else if (errCode<0x10000)
        return 0;
    else
        ret = errCode-0x10000;

    StringAttr vers;
    replyBuffer.read(vers);
    ver.append(vers);
    return ret;
}

unsigned getRemoteVersion(ISocket *origSock, StringBuffer &ver)
{
    // used to have a global critical section here
    if (!origSock)
        return 0;

    Owned<ISocket> socket = checkSocketSecure(origSock);

    unsigned ret;
    MemoryBuffer sendbuf;
    initSendBuffer(sendbuf);
    sendbuf.append((RemoteFileCommandType)RFCgetver);
    sendbuf.append((unsigned)RFCgetver);
    MemoryBuffer reply;
    try
    {
        sendBuffer(socket, sendbuf);
        receiveBuffer(socket, reply, 1 ,4096);
        unsigned errCode;
        reply.read(errCode);
        if (errCode==RFSERR_InvalidCommand)
        {
            ver.append("DS V1.0");
            return 10;
        }
        else if (errCode==0)
            ret = 11;
        else if (errCode<0x10000)
            return 0;
        else
            ret = errCode-0x10000;
    }
    catch (IException *e)
    {
        EXCLOG(e);
        ::Release(e);
        return 0;
    }
    StringAttr vers;
    reply.read(vers);
    ver.append(vers);
    return ret;
}

/////////////////////////


//////////////

extern unsigned stopRemoteServer(ISocket * socket)
{
    // used to have a global critical section here
    if (!socket)
        return 0;
    MemoryBuffer sendbuf;
    initSendBuffer(sendbuf);
    sendbuf.append((RemoteFileCommandType)RFCstop);
    sendbuf.append((unsigned)RFCstop);
    MemoryBuffer replybuf;
    unsigned errCode = RFSERR_InvalidCommand;
    try
    {
        sendBuffer(socket, sendbuf);
        receiveBuffer(socket, replybuf, NORMAL_RETRIES, 1024);
        replybuf.read(errCode);
    }
    catch (IJSOCK_Exception *e)
    {
        if ((e->errorCode()!=JSOCKERR_broken_pipe)&&(e->errorCode()!=JSOCKERR_graceful_close)) 
            EXCLOG(e);
        else
            errCode = 0;
    }
    catch (IException *e)
    {
        EXCLOG(e);
        ::Release(e);
    }
    return errCode;
}

int setDafsTrace(ISocket * socket,byte flags)
{
    if (!socket)
    {
        byte ret = traceFlags;
        traceFlags = flags;
        return ret;
    }
    MemoryBuffer sendbuf;
    initSendBuffer(sendbuf);
    sendbuf.append((RemoteFileCommandType)RFCsettrace).append(flags);
    MemoryBuffer replybuf;
    try
    {
        sendBuffer(socket, sendbuf);
        receiveBuffer(socket, replybuf, NORMAL_RETRIES, 1024);
        int retcode;
        replybuf.read(retcode);
        return retcode;
    }
    catch (IException *e)
    {
        EXCLOG(e);
        ::Release(e);
    }
    return -1;
}

int setDafsThrottleLimit(ISocket * socket, ThrottleClass throttleClass, unsigned throttleLimit, unsigned throttleDelayMs, unsigned throttleCPULimit, unsigned queueLimit, StringBuffer *errMsg)
{
    assertex(socket);
    MemoryBuffer sendbuf;
    initSendBuffer(sendbuf);
    sendbuf.append((RemoteFileCommandType)RFCsetthrottle2).append((unsigned)throttleClass).append(throttleLimit);
    sendbuf.append(throttleDelayMs).append(throttleCPULimit).append(queueLimit);
    MemoryBuffer replybuf;
    try
    {
        sendBuffer(socket, sendbuf);
        receiveBuffer(socket, replybuf, NORMAL_RETRIES, 1024);
        int retcode;
        replybuf.read(retcode);
        if (retcode && errMsg && replybuf.remaining())
            replybuf.read(*errMsg);
        return retcode;
    }
    catch (IException *e)
    {
        EXCLOG(e);
        ::Release(e);
    }
    return -1;
}

int getDafsInfo(ISocket * socket, unsigned level, StringBuffer &retstr)
{
    if (!socket)
    {
        retstr.append(VERSTRING);
        return 0;
    }
    MemoryBuffer sendbuf;
    initSendBuffer(sendbuf);
    sendbuf.append((RemoteFileCommandType)RFCgetinfo).append(level);
    MemoryBuffer replybuf;
    try
    {
        sendBuffer(socket, sendbuf);
        receiveBuffer(socket, replybuf, 1);
        int retcode;
        replybuf.read(retcode);
        if (retcode==0)
        {
            StringAttr s;
            replybuf.read(s);
            retstr.append(s);
        }
        return retcode;
    }
    catch (IException *e)
    {
        EXCLOG(e);
        ::Release(e);
    }
    return -1;
}



void remoteExtractBlobElements(const SocketEndpoint &ep,const char * prefix, const char * filename, ExtractedBlobArray & extracted)
{
    Owned<CRemoteFile> file = new CRemoteFile (ep,filename);
    file->remoteExtractBlobElements(prefix, extracted);
}

//====================================================================================================


class CAsyncCommandManager
{
    class CAsyncJob: public CInterface
    {
        class cThread: public Thread
        {
            CAsyncJob *parent;
        public:
            cThread(CAsyncJob *_parent)
                : Thread("CAsyncJob")
            {
                parent = _parent;
            }
            int run()
            {
                int ret = -1;
                try {
                    ret = parent->run();
                    parent->setDone();
                }
                catch (IException *e)
                {
                    parent->setException(e);
                }
                parent->signal();
                return ret;
            }
        } *thread;
        StringAttr uuid;
        CAsyncCommandManager &parent;
    public:
        CAsyncJob(CAsyncCommandManager &_parent, const char *_uuid)
            : uuid(_uuid), parent(_parent)
        {
            thread = new cThread(this);
            hash = hashc((const byte *)uuid.get(),uuid.length(),~0U);
        }
        ~CAsyncJob()
        {
            thread->join();
            thread->Release();
        }
        static void destroy(CAsyncJob *j)
        {
            j->Release();
        }
        void signal()
        {
            parent.signal();
        }
        void start()
        {
            parent.wait();
            thread->start();
        }
        void join()
        {
            thread->join();
        }
        static unsigned getHash(const char *key)
        {
            return hashc((const byte *)key,strlen(key),~0U);
        }
        static CAsyncJob* create(const char *key) { assertex(!"CAsyncJob::create not implemented"); return NULL; }
        unsigned hash;
        bool eq(const char *key)
        {
            return stricmp(key,uuid.get())==0;
        }
        virtual int run()=0;
        virtual void setException(IException *e)=0;
        virtual void setDone()=0;
    };

    class CAsyncCopySection: public CAsyncJob
    {
        Owned<IFile> src;
        RemoteFilename dst;
        offset_t toOfs;
        offset_t fromOfs;
        offset_t size;
        CFPmode mode; // not yet supported
        CriticalSection sect;
        offset_t done;
        offset_t total;
        Semaphore finished;
        AsyncCommandStatus status;
        Owned<IException> exc;
    public:
        CAsyncCopySection(CAsyncCommandManager &parent, const char *_uuid, const char *fromFile, const char *toFile, offset_t _toOfs, offset_t _fromOfs, offset_t _size)
            : CAsyncJob(parent, _uuid)
        {
            status = ACScontinue;
            src.setown(createIFile(fromFile));
            dst.setRemotePath(toFile);
            toOfs = _toOfs;
            fromOfs = _fromOfs;
            size = _size;
            mode = CFPcontinue;
            done = 0;
            total = (offset_t)-1;
        }
        AsyncCommandStatus poll(offset_t &_done, offset_t &_total,unsigned timeout)
        {
            if (timeout&&finished.wait(timeout))
                finished.signal();      // may need to call again
            CriticalBlock block(sect);
            if (exc)
                throw exc.getClear();
            _done = done;
            _total = total;
            return status;
        }
        int run()
        {
            class cProgress: implements ICopyFileProgress
            {
                CriticalSection &sect;
                CFPmode &mode;
                offset_t &done;
                offset_t &total;
            public:
                cProgress(CriticalSection &_sect,offset_t &_done,offset_t &_total,CFPmode &_mode)
                    : sect(_sect), mode(_mode), done(_done), total(_total)
                {
                }
                CFPmode onProgress(offset_t sizeDone, offset_t totalSize)
                {
                    CriticalBlock block(sect);
                    done = sizeDone;
                    total = totalSize;
                    return mode;
                }
            } progress(sect,total,done,mode);
            src->copySection(dst,toOfs, fromOfs, size, &progress);  // exceptions will be handled by base class
            return 0;
        }
        void setException(IException *e)
        {
            EXCLOG(e,"CAsyncCommandManager::CAsyncJob");
            CriticalBlock block(sect);
            if (exc.get())
                e->Release();
            else
                exc.setown(e);
            status = ACSerror;
        }
        void setDone()
        {
            CriticalBlock block(sect);
            finished.signal();
            status = ACSdone;
        }
    };

    CMinHashTable<CAsyncJob> jobtable;
    CriticalSection sect;
    Semaphore threadsem;
    unsigned limit;

public:
    CAsyncCommandManager(unsigned _limit) : limit(_limit)
    {
        if (limit) // 0 == unbound
            threadsem.signal(limit); // max number of async jobs
    }
    void join()
    {
        CriticalBlock block(sect);
        unsigned i;
        CAsyncJob *j=jobtable.first(i);
        while (j) {
            j->join();
            j=jobtable.next(i);
        }
    }

    void signal()
    {
        if (limit)
            threadsem.signal();
    }

    void wait()
    {
        if (limit)
            threadsem.wait();
    }

    AsyncCommandStatus copySection(const char *uuid, const char *fromFile, const char *toFile, offset_t toOfs, offset_t fromOfs, offset_t size, offset_t &done, offset_t &total, unsigned timeout)
    {
        // return 0 if continuing, 1 if done
        CAsyncCopySection * job;
        Linked<CAsyncJob> cjob;
        {
            CriticalBlock block(sect);
            cjob.set(jobtable.find(uuid,false));
            if (cjob) {
                job = QUERYINTERFACE(cjob.get(),CAsyncCopySection);
                if (!job) {
                    throw MakeStringException(-1,"Async job ID mismatch");
                }
            }
            else {
                job = new CAsyncCopySection(*this, uuid, fromFile, toFile, toOfs, fromOfs, size);
                cjob.setown(job);
                jobtable.add(cjob.getLink());
                cjob->start();
            }
        }
        AsyncCommandStatus ret = ACSerror;
        Owned<IException> rete;
        try {
            ret = job->poll(done,total,timeout);
        }
        catch (IException * e) {
            rete.setown(e);
        }
        if ((ret!=ACScontinue)||rete.get()) {
            job->join();
            CriticalBlock block(sect);
            jobtable.remove(job);
            if (rete.get())
                throw rete.getClear();
        }
        return ret;
    }
};


//====================================================================================================



inline void appendErr(MemoryBuffer &reply, unsigned e)
{
    reply.append(e).append(getRFSERRText(e));
}

#define MAPCOMMAND(c,p) case c: { this->p(msg, reply) ; break; }
#define MAPCOMMANDCLIENT(c,p,client) case c: { this->p(msg, reply, client); break; }
#define MAPCOMMANDCLIENTTESTSOCKET(c,p,client) case c: { testSocketFlag = true; this->p(msg, reply, client); break; }
#define MAPCOMMANDCLIENTTHROTTLE(c,p,client,throttler) case c: { this->p(msg, reply, client, throttler); break; }
#define MAPCOMMANDSTATS(c,p,stats) case c: { this->p(msg, reply, stats); break; }
#define MAPCOMMANDCLIENTSTATS(c,p,client,stats) case c: { this->p(msg, reply, client, stats); break; }

static unsigned ClientCount = 0;
static unsigned MaxClientCount = 0;
static CriticalSection ClientCountSect;

#define DEFAULT_THROTTLOG_LOG_INTERVAL_SECS 60 // log total throttled delay period


class CClientStats : public CInterface
{
public:
    CClientStats(const char *_client) : client(_client), count(0), bRead(0), bWritten(0) { }
    const char *queryFindString() const { return client; }
    inline void addRead(unsigned __int64 len)
    {
        bRead += len;
    }
    inline void addWrite(unsigned __int64 len)
    {
        bWritten += len;
    }
    void getStatus(StringBuffer & info) const
    {
        info.appendf("Client %s - %" I64F "d requests handled, bytes read = %" I64F "d, bytes written = % " I64F "d",
            client.get(), count, bRead.load(), bWritten.load()).newline();
    }

    StringAttr client;
    unsigned __int64 count;
    std::atomic<unsigned __int64> bRead;
    std::atomic<unsigned __int64> bWritten;
};

class CClientStatsTable : public OwningStringSuperHashTableOf<CClientStats>
{
    typedef OwningStringSuperHashTableOf<CClientStats> PARENT;
    CriticalSection crit;
    unsigned cmdStats[RFCmax];

    static int compareElement(void* const *ll, void* const *rr)
    {
        const CClientStats *l = (const CClientStats *) *ll;
        const CClientStats *r = (const CClientStats *) *rr;
        if (l->count == r->count)
            return 0;
        else if (l->count<r->count)
            return 1;
        else
            return -1;
    }
public:
    CClientStatsTable()
    {
        memset(&cmdStats[0], 0, sizeof(cmdStats));
    }
    ~CClientStatsTable()
    {
        _releaseAll();
    }
    CClientStats *getClientReference(RemoteFileCommandType cmd, const char *client)
    {
        CriticalBlock b(crit);
        CClientStats *stats = PARENT::find(client);
        if (!stats)
        {
            stats = new CClientStats(client);
            PARENT::replace(*stats);
        }
        if (cmd<RFCmax) // i.e. ignore duff command (which will be traced), but still record client connected
            cmdStats[cmd]++;
        ++stats->count;
        return LINK(stats);
    }
    StringBuffer &getInfo(StringBuffer &info, unsigned level=1)
    {
        CriticalBlock b(crit);
        unsigned __int64 totalCmds = 0;
        for (unsigned c=0; c<RFCmax; c++)
            totalCmds += cmdStats[c];
        unsigned totalClients = PARENT::ordinality();
        info.appendf("Commands processed = %" I64F "u, unique clients = %u", totalCmds, totalClients);
        if (totalCmds)
        {
            info.append("Command stats:").newline();
            for (unsigned c=0; c<RFCmax; c++)
            {
                unsigned __int64 count = cmdStats[c];
                if (count)
                    info.append(getRFCText(c)).append(": ").append(count).newline();
            }
        }
        if (totalClients)
        {
            SuperHashIteratorOf<CClientStats> iter(*this);
            PointerArrayOf<CClientStats> elements;
            ForEach(iter)
            {
                CClientStats &elem = iter.query();
                elements.append(&elem);
            }
            elements.sort(&compareElement);
            if (level < 10)
            {
                // list up to 10 clients ordered by # of commands processed
                unsigned max=elements.ordinality();
                if (max>10)
                    max = 10; // cap
                info.append("Top 10 clients:").newline();
                for (unsigned e=0; e<max; e++)
                {
                    const CClientStats &element = *elements.item(e);
                    element.getStatus(info);
                }
            }
            else // list all
            {
                info.append("All clients:").newline();
                ForEachItemIn(e, elements)
                {
                    const CClientStats &element = *elements.item(e);
                    element.getStatus(info);
                }
            }
        }
        return info;
    }
    void reset()
    {
        CriticalBlock b(crit);
        memset(&cmdStats[0], 0, sizeof(cmdStats));
        kill();
    }
};

interface IRemoteActivity : extends IInterface
{
    virtual const void *nextRow(MemoryBufferBuilder &outBuilder, size32_t &sz) = 0;
    virtual unsigned __int64 queryProcessed() const = 0;
    virtual IOutputMetaData *queryOutputMeta() const = 0;
    virtual StringBuffer &getInfoStr(StringBuffer &out) const = 0;
    virtual void serializeCursor(MemoryBuffer &tgt) const = 0;
    virtual void restoreCursor(MemoryBuffer &src) = 0;
    virtual bool isGrouped() const = 0;
};

class CRemoteRequest : public CSimpleInterfaceOf<IInterface>
{
    OutputFormat format;
    unsigned __int64 replyLimit;
    Linked<IRemoteActivity> activity;
    Linked<ICompressor> compressor;
public:
    CRemoteRequest(OutputFormat _format, ICompressor *_compressor, unsigned __int64 _replyLimit, IRemoteActivity *_activity)
        : format(_format), compressor(_compressor), replyLimit(_replyLimit), activity(_activity)
    {
    }
    OutputFormat queryFormat() const { return format; }
    unsigned __int64 queryReplyLimit() const { return replyLimit; }
    IRemoteActivity *queryActivity() const { return activity; }
    ICompressor *queryCompressor() const { return compressor; }
};

enum OpenFileFlag { of_null=0x0, of_key=0x01 };
struct OpenFileInfo
{
    OpenFileInfo() { }
    OpenFileInfo(int _handle, IFileIO *_fileIO, StringAttrItem *_filename) : handle(_handle), fileIO(_fileIO), filename(_filename) { }
    OpenFileInfo(int _handle, CRemoteRequest *_remoteRequest, StringAttrItem *_filename)
        : handle(_handle), remoteRequest(_remoteRequest), filename(_filename) { }
    Linked<IFileIO> fileIO;
    Linked<CRemoteRequest> remoteRequest;
    Linked<StringAttrItem> filename; // for debug
    int handle = 0;
    unsigned flags = 0;
};



static IOutputMetaData *getTypeInfoOutputMetaData(IPropertyTree &actNode, const char *typePropName, bool grouped)
{
    IPropertyTree *json = actNode.queryPropTree(typePropName);
    if (json)
        return createTypeInfoOutputMetaData(*json, grouped);
    else
    {
        StringBuffer binTypePropName(typePropName);
        const char *jsonBin = actNode.queryProp(binTypePropName.append("Bin"));
        if (!jsonBin)
            return nullptr;
        MemoryBuffer mb;
        JBASE64_Decode(jsonBin, mb);
        return createTypeInfoOutputMetaData(mb, grouped);
    }
}

class CRemoteDiskBaseActivity : public CSimpleInterfaceOf<IRemoteActivity>, implements IVirtualFieldCallback
{
protected:
    StringAttr fileName; // physical filename
    Linked<IOutputMetaData> inMeta, outMeta;
    unsigned __int64 processed = 0;
    Owned<const IDynamicTransform> translator;
    bool outputGrouped = false;
    bool opened = false;
    bool eofSeen = false;
    const RtlRecord *record = nullptr;
    RowFilter filters;
    // virtual field values
    StringAttr logicalFilename;

    void initCommon(IPropertyTree &config)
    {
        fileName.set(config.queryProp("fileName"));
        if (isEmptyString(fileName))
            throw createDafsException(DAFSERR_cmdstream_protocol_failure, "CRemoteDiskBaseActivity: fileName missing");

        record = &inMeta->queryRecordAccessor(true);
        translator.setown(createRecordTranslator(outMeta->queryRecordAccessor(true), *record));
        Owned<IPropertyTreeIterator> filterIter = config.getElements("keyFilter");
        ForEach(*filterIter)
            filters.addFilter(*record, filterIter->query().queryProp(nullptr));
        logicalFilename.set(config.queryProp("virtualFields/logicalFilename"));
    }
public:
    IMPLEMENT_IINTERFACE_USING(CSimpleInterfaceOf<IRemoteActivity>)

    CRemoteDiskBaseActivity(IPropertyTree &config)
    {
    }
// IRemoteActivity impl.
    virtual unsigned __int64 queryProcessed() const override
    {
        return processed;
    }
    virtual IOutputMetaData *queryOutputMeta() const override
    {
        return outMeta;
    }
    virtual bool isGrouped() const override
    {
        return outputGrouped;
    }
    virtual void serializeCursor(MemoryBuffer &tgt) const override
    {
        throwUnexpected();
    }
    virtual void restoreCursor(MemoryBuffer &src) override
    {
        throwUnexpected();
    }
//interface IVirtualFieldCallback
    virtual const char * queryLogicalFilename(const void * row) override
    {
        return logicalFilename.str();
    }
    virtual unsigned __int64 getFilePosition(const void * row) override
    {
        throwUnexpected();
    }
    virtual unsigned __int64 getLocalFilePosition(const void * row) override
    {
        throwUnexpected();
    }
    virtual const byte * lookupBlob(unsigned __int64 id) override
    {
        throwUnexpected();
    }
};

class CRemoteDiskReadActivity : public CRemoteDiskBaseActivity
{
    typedef CRemoteDiskBaseActivity PARENT;

    CThorContiguousRowBuffer prefetchBuffer;
    Owned<ISourceRowPrefetcher> prefetcher;
    Owned<ISerialStream> inputStream;
    Owned<IFileIO> iFileIO;
    unsigned __int64 chooseN = 0;
    unsigned __int64 startPos = 0;
    bool compressed = false;
    bool inputGrouped = false;
    bool cursorDirty = false;
    mutable bool eogPending = false;
    mutable bool someInGroup = false;
    RtlDynRow *filterRow = nullptr;
    // virtual field values
    unsigned partNum = 0;
    offset_t baseFpos = 0;

    void checkOpen()
    {
        if (opened)
        {
            if (!cursorDirty)
                return;
            if (prefetchBuffer.tell() != startPos)
            {
                inputStream->reset(startPos);
                prefetchBuffer.clearStream();
                prefetchBuffer.setStream(inputStream);
            }
            eofSeen = false;
            cursorDirty = false;
            return;
        }

        OwnedIFile iFile = createIFile(fileName);
        assertex(iFile);
        iFileIO.setown(createCompressedFileReader(iFile));
        if (iFileIO)
        {
            if (!compressed)
            {
                WARNLOG("meta info did not mark file '%s' as compressed, but detected file as compressed", fileName.get());
                compressed = true;
            }
        }
        else
        {
            iFileIO.setown(iFile->open(IFOread));
            if (!iFileIO)
                throw createDafsExceptionV(DAFSERR_cmdstream_protocol_failure, "Failed to open: '%s'", fileName.get());
            if (compressed)
            {
                WARNLOG("meta info marked file '%s' as compressed, but detected file as uncompressed", fileName.get());
                compressed = false;
            }
        }
        inputStream.setown(createFileSerialStream(iFileIO, startPos));
        prefetchBuffer.setStream(inputStream);
        prefetcher.setown(inMeta->createDiskPrefetcher());

        opened = true;
        eofSeen = false;
    }
    void close()
    {
        iFileIO.clear();
        opened = false;
        eofSeen = true;
    }
    inline bool fieldFilterMatch(const void * buffer)
    {
        if (filters.numFilterFields())
        {
            filterRow->setRow(buffer, 0);
            return filters.matches(*filterRow);
        }
        else
            return true;
    }
public:
    CRemoteDiskReadActivity(IPropertyTree &config) : PARENT(config), prefetchBuffer(nullptr)
    {
        compressed = config.getPropBool("compressed");
        inputGrouped = config.getPropBool("inputGrouped", false);
        outputGrouped = config.getPropBool("outputGrouped", false);
        chooseN = config.getPropInt64("chooseN", defaultFileStreamChooseNLimit);
        if (!inputGrouped && outputGrouped)
            outputGrouped = false; // perhaps should fire error
        inMeta.setown(getTypeInfoOutputMetaData(config, "input", inputGrouped));
        outMeta.setown(getTypeInfoOutputMetaData(config, "output", outputGrouped));
        if (!outMeta)
            outMeta.set(inMeta);

        partNum = config.getPropInt("virtualFields/partNum");
        baseFpos = (offset_t)config.getPropInt64("virtualFields/baseFpos");

        initCommon(config);
        if (config.hasProp("keyFilter"))
            filterRow = new RtlDynRow(*record);
    }
    ~CRemoteDiskReadActivity()
    {
        delete filterRow;
    }
// IRemoteActivity impl.
    virtual const void *nextRow(MemoryBufferBuilder &outBuilder, size32_t &retSz) override
    {
        if (eogPending || eofSeen)
        {
            eogPending = false;
            someInGroup = false;
            return nullptr;
        }
        checkOpen();
        while (!eofSeen && (processed < chooseN))
        {
            while (!prefetchBuffer.eos())
            {
                prefetcher->readAhead(prefetchBuffer);
                bool eog = false;
                if (inputGrouped)
                    prefetchBuffer.read(sizeof(eog), &eog);
                const byte *next = prefetchBuffer.queryRow();
                size32_t rowSz; // use local var instead of reference param for efficiency
                if (fieldFilterMatch(next))
                    rowSz = translator->translate(outBuilder, *this, next);
                else
                    rowSz = 0;
                prefetchBuffer.finishedRow();
                const void *ret = outBuilder.getSelf();
                outBuilder.finishRow(rowSz);

                if (rowSz)
                {
                    processed++;
                    eogPending = eog;
                    someInGroup = true;
                    retSz = rowSz;
                    return ret;
                }
                else if (eog)
                {
                    eogPending = false;
                    if (someInGroup)
                    {
                        someInGroup = false;
                        return nullptr;
                    }
                }
            }
            eofSeen = true;
        }
        close();
        retSz = 0;
        return nullptr;
    }
    virtual void serializeCursor(MemoryBuffer &tgt) const override
    {
        tgt.append(prefetchBuffer.tell());
        tgt.append(processed);
        tgt.append(someInGroup);
        tgt.append(eogPending);
    }
    virtual void restoreCursor(MemoryBuffer &src) override
    {
        cursorDirty = true;
        src.read(startPos);
        src.read(processed);
        src.read(someInGroup);
        src.read(eogPending);
    }
    virtual StringBuffer &getInfoStr(StringBuffer &out) const override
    {
        return out.appendf("diskread[%s]", fileName.get());
    }
    virtual bool isGrouped() const override
    {
        return outputGrouped;
    }
//interface IVirtualFieldCallback
    virtual unsigned __int64 getFilePosition(const void * row) override
    {
        return prefetchBuffer.tell() + baseFpos;
    }
    virtual unsigned __int64 getLocalFilePosition(const void * row) override
    {
        return makeLocalFposOffset(partNum, prefetchBuffer.tell());
    }
    virtual const byte * lookupBlob(unsigned __int64 id) override
    {
        throwUnexpected();
    }
};


IRemoteActivity *createRemoteDiskRead(IPropertyTree &actNode)
{
    return new CRemoteDiskReadActivity(actNode);
}

class CRemoteIndexBaseActivity : public CRemoteDiskBaseActivity
{
    typedef CRemoteDiskBaseActivity PARENT;

protected:
    bool isTlk = false;
    bool allowPreload = false;
    unsigned fileCrc = 0;
    Owned<IKeyIndex> keyIndex;
    Owned<IKeyManager> keyManager;

    void checkOpen()
    {
        if (opened)
            return;
        Owned<IFile> indexFile = createIFile(fileName);
        CDateTime modTime;
        indexFile->getTime(nullptr, &modTime, nullptr);
        time_t modTimeTT = modTime.getSimple();
        CRC32 crc32(fileCrc);
        crc32.tally(sizeof(time_t), &modTimeTT);
        unsigned crc = crc32.get();

        keyIndex.setown(createKeyIndex(fileName, crc, isTlk, allowPreload));
        keyManager.setown(createLocalKeyManager(*record, keyIndex, nullptr, true));
        filters.createSegmentMonitors(keyManager);
        keyManager->finishSegmentMonitors();
        keyManager->reset();

        opened = true;
    }
    void close()
    {
        keyManager.clear();
        keyIndex.clear();
        opened = false;
        eofSeen = true;
    }
public:
    CRemoteIndexBaseActivity(IPropertyTree &config) : PARENT(config)
    {
        isTlk = config.getPropBool("isTlk");
        allowPreload = config.getPropBool("allowPreload");
        fileCrc = config.getPropInt("crc");
    }
};

class CRemoteIndexReadActivity : public CRemoteIndexBaseActivity
{
    typedef CRemoteIndexBaseActivity PARENT;

    unsigned __int64 chooseN = 0;
public:
    CRemoteIndexReadActivity(IPropertyTree &config) : PARENT(config)
    {
        chooseN = config.getPropInt64("chooseN", defaultFileStreamChooseNLimit);
        inMeta.setown(getTypeInfoOutputMetaData(config, "input", false));
        outMeta.setown(getTypeInfoOutputMetaData(config, "output", false));
        if (!outMeta)
            outMeta.set(inMeta);

        initCommon(config);
    }
// IRemoteActivity impl.
    virtual const void *nextRow(MemoryBufferBuilder &outBuilder, size32_t &retSz) override
    {
        if (eofSeen)
            return nullptr;
        checkOpen();
        if (!eofSeen)
        {
            if (processed < chooseN)
            {
                while (keyManager->lookup(true))
                {
                    const byte *keyRow = keyManager->queryKeyBuffer();
                    retSz = translator->translate(outBuilder, *this, keyRow);
                    if (retSz)
                    {
                        const void *ret = outBuilder.getSelf();
                        outBuilder.finishRow(retSz);
                        ++processed;
                        return ret;
                    }
                }
                retSz = 0;
            }
            eofSeen = true;
        }
        close();
        return nullptr;
    }
    virtual void serializeCursor(MemoryBuffer &tgt) const override
    {
        keyManager->serializeCursorPos(tgt);
        tgt.append(processed);

/* JCSMORE (see HPCC-19640), serialize seek/scan data to client
        tgt.append(keyManager->querySeeks());
        tgt.append(keyManager->queryScans());
*/
    }
    virtual void restoreCursor(MemoryBuffer &src) override
    {
        checkOpen();
        eofSeen = false;
        keyManager->deserializeCursorPos(src);
        src.read(processed);
    }
    virtual StringBuffer &getInfoStr(StringBuffer &out) const override
    {
        return out.appendf("indexread[%s]", fileName.get());
    }
};


IRemoteActivity *createRemoteIndexRead(IPropertyTree &actNode)
{
    return new CRemoteIndexReadActivity(actNode);
}


// create a { unsigned8 } output meta for the count
static const RtlIntTypeInfo indexCountFieldType(type_unsigned|type_int, 8);
static const RtlFieldStrInfo indexCountField("count", nullptr, &indexCountFieldType);
static const RtlFieldInfo * const indexCountFields[2] = { &indexCountField, nullptr };
static const RtlRecordTypeInfo indexCountRecord(type_record, 2, indexCountFields);

class CRemoteIndexCountActivity : public CRemoteIndexBaseActivity
{
    typedef CRemoteIndexBaseActivity PARENT;

    unsigned __int64 rowLimit = 0;

public:
    CRemoteIndexCountActivity(IPropertyTree &config) : PARENT(config)
    {
        rowLimit = config.getPropInt64("chooseN");

        inMeta.setown(getTypeInfoOutputMetaData(config, "input", false));
        outMeta.setown(new CDynamicOutputMetaData(indexCountRecord));

        initCommon(config);
    }
// IRemoteActivity impl.
    virtual const void *nextRow(MemoryBufferBuilder &outBuilder, size32_t &retSz) override
    {
        if (eofSeen)
            return nullptr;
        checkOpen();
        unsigned __int64 count = 0;
        if (!eofSeen)
        {
            if (rowLimit)
                count = keyManager->checkCount(rowLimit);
            else
                count = keyManager->getCount();
        }
        void *tgt = outBuilder.ensureCapacity(sizeof(count), "count");
        const void *ret = outBuilder.getSelf();
        memcpy(tgt, &count, sizeof(count));
        outBuilder.finishRow(sizeof(count));
        close();
        return ret;
    }
    virtual StringBuffer &getInfoStr(StringBuffer &out) const override
    {
        return out.appendf("indexcount[%s]", fileName.get());
    }
};


IRemoteActivity *createRemoteIndexCount(IPropertyTree &actNode)
{
    return new CRemoteIndexCountActivity(actNode);
}

void checkExpiryTime(IPropertyTree &metaInfo)
{
    const char *expiryTime = metaInfo.queryProp("expiryTime");
    if (isEmptyString(expiryTime))
        throw createDafsException(DAFSERR_cmdstream_invalidexpiry, "createRemoteActivity: invalid expiry specification");

    CDateTime expiryTimeDt;
    try
    {
        expiryTimeDt.setString(expiryTime);
    }
    catch (IException *e)
    {
        throw createDafsException(DAFSERR_cmdstream_invalidexpiry, "createRemoteActivity: invalid expiry specification");
    }
    CDateTime nowDt;
    nowDt.setNow();
    if (nowDt >= expiryTimeDt)
        throw createDafsException(DAFSERR_cmdstream_authexpired, "createRemoteActivity: authorization expired");
}

void verifyMetaInfo(IPropertyTree &actNode, bool authorizedOnly, const IPropertyTree *keyPairInfo)
{
    if (!authorizedOnly) // if configured false, allows unencrypted meta info
    {
        if (actNode.hasProp("fileName"))
            return;
    }
    StringBuffer metaInfoB64;
    actNode.getProp("metaInfo", metaInfoB64);
    if (0 == metaInfoB64.length())
        throw createDafsException(DAFSERR_cmdstream_protocol_failure, "createRemoteActivity: missing metaInfo");

    MemoryBuffer compressedMetaInfoMb;
    JBASE64_Decode(metaInfoB64.str(), compressedMetaInfoMb);
    MemoryBuffer decompressedMetaInfoMb;
    fastLZDecompressToBuffer(decompressedMetaInfoMb, compressedMetaInfoMb);
    Owned<IPropertyTree> metaInfoEnvelope = createPTree(decompressedMetaInfoMb);

    Owned<IPropertyTree> metaInfo;
#if defined(_USE_OPENSSL) && !defined(_WIN32)
    MemoryBuffer metaInfoBlob;
    metaInfoEnvelope->getPropBin("metaInfoBlob", metaInfoBlob);

    bool isSigned = metaInfoBlob.length() != 0;
    if (authorizedOnly && !isSigned)
        throw createDafsException(DAFSERR_cmdstream_unauthorized, "createRemoteActivity: unathorized");

    if (isSigned)
    {
        metaInfo.setown(createPTree(metaInfoBlob));

        // version for future use
        unsigned securityVersion = metaInfo->getPropInt("version");

        const char *keyPairName = metaInfo->queryProp("keyPairName");

        StringBuffer metaInfoSignature;
        if (!metaInfoEnvelope->getProp("signature", metaInfoSignature))
            throw createDafsException(DAFSERR_cmdstream_unauthorized, "createRemoteActivity: missing signature");

        VStringBuffer keyPairPath("KeyPair[@name=\"%s\"]", keyPairName);
        IPropertyTree *keyPair = keyPairInfo->queryPropTree(keyPairPath);
        if (!keyPair)
            throw createDafsException(DAFSERR_cmdstream_unauthorized, "createRemoteActivity: missing key pair definition");
        const char *publicKeyFName = keyPair->queryProp("@publicKey");
        if (isEmptyString(publicKeyFName))
            throw createDafsException(DAFSERR_cmdstream_unauthorized, "createRemoteActivity: missing public key definition");
        Owned<CLoadedKey> publicKey = loadPublicKeyFromFile(publicKeyFName, nullptr); // NB: if cared could cache loaded keys
        if (!digiVerify(metaInfoSignature, metaInfoBlob.length(), metaInfoBlob.bytes(), *publicKey))
            throw createDafsException(DAFSERR_cmdstream_unauthorized, "createRemoteActivity: signature verification failed");

        checkExpiryTime(*metaInfo);
    }
    else
#endif
        metaInfo.set(metaInfoEnvelope);

    IPropertyTree *fileInfo = metaInfo->queryPropTree("FileInfo");
    assertex(fileInfo);

    // extra filename based on part/copy.
    assertex(actNode.hasProp("filePart"));
    unsigned partNum = actNode.getPropInt("filePart");
    assertex(partNum);
    unsigned partCopy = actNode.getPropInt("filePartCopy", 1);

    VStringBuffer xpath("Part[%u]/Copy[%u]/@filePath", partNum, partCopy);
    StringBuffer partFileName;
    fileInfo->getProp(xpath, partFileName);
    if (!partFileName.length())
        throw createDafsException(DAFSERR_cmdstream_protocol_failure, "createRemoteActivity: invalid file info");

    actNode.setProp("fileName", partFileName.str());
    verifyex(actNode.removeProp("metaInfo")); // no longer needed
}

IRemoteActivity *createRemoteActivity(IPropertyTree &actNode, bool authorizedOnly, const IPropertyTree *keyPairInfo)
{
    verifyMetaInfo(actNode, authorizedOnly, keyPairInfo);

    const char *partFileName = actNode.queryProp("fileName");
    const char *kindStr = actNode.queryProp("kind");
    ThorActivityKind kind = TAKnone;
    if (kindStr)
    {
        if (strieq("diskread", kindStr))
            kind = TAKdiskread;
        else if (strieq("indexread", kindStr))
            kind = TAKindexread;
        else if (strieq("indexcount", kindStr))
            kind = TAKindexcount;
        // else - auto-detect
    }

    Owned<IRemoteActivity> activity;
    switch (kind)
    {
        case TAKdiskread:
        {
            activity.setown(createRemoteDiskRead(actNode));
            break;
        }
        case TAKindexread:
        {
            activity.setown(createRemoteIndexRead(actNode));
            break;
        }
        case TAKindexcount:
        {
            activity.setown(createRemoteIndexCount(actNode));
            break;
        }
        default: // auto-detect file format
        {
            const char *action = actNode.queryProp("action");
            if (isIndexFile(partFileName))
            {
                if (!isEmptyString(action))
                {
                    if (streq("count", action))
                        activity.setown(createRemoteIndexCount(actNode));
                    else
                        throw createDafsExceptionV(DAFSERR_cmdstream_protocol_failure, "Unknown action '%s' on index '%s'", action, partFileName);
                }
                else
                    activity.setown(createRemoteIndexRead(actNode));
            }
            else // flat file
            {
                if (!isEmptyString(action))
                {
                    if (streq("count", action))
                        throw createDafsException(DAFSERR_cmdstream_protocol_failure, "Remote Disk Counts currently unsupported");
                    else
                        throw createDafsExceptionV(DAFSERR_cmdstream_protocol_failure, "Unknown action '%s' on flat file '%s'", action, partFileName);
                }
                else
                    activity.setown(createRemoteDiskRead(actNode));
            }
            break;
        }

    }
    return activity.getClear();
}

IRemoteActivity *createOutputActivity(IPropertyTree &requestTree, bool authorizedOnly, const IPropertyTree *keyPairInfo)
{
    IPropertyTree *actNode = requestTree.queryPropTree("node");
    assertex(actNode);
    return createRemoteActivity(*actNode, authorizedOnly, keyPairInfo);
}

#define MAX_KEYDATA_SZ 0x10000

class CRemoteFileServer : implements IRemoteFileServer, public CInterface
{
    class CThrottler;
    class CRemoteClientHandler : implements ISocketSelectNotify, public CInterface
    {
    public:
        CRemoteFileServer *parent;
        Owned<ISocket> socket;
        StringAttr peerName;
        Owned<IAuthenticatedUser> user;
        MemoryBuffer msg;
        bool selecthandled;
        size32_t left;
        StructArrayOf<OpenFileInfo> openFiles;
        Owned<IDirectoryIterator> opendir;
        unsigned            lasttick, lastInactiveTick;
        atomic_t            &globallasttick;
        unsigned            previdx;        // for debug


        IMPLEMENT_IINTERFACE;

        CRemoteClientHandler(CRemoteFileServer *_parent,ISocket *_socket,IAuthenticatedUser *_user,atomic_t &_globallasttick)
            : socket(_socket), user(_user), globallasttick(_globallasttick)
        {
            previdx = (unsigned)-1;
            StringBuffer peerBuf;
            char name[256];
            name[0] = 0;
            int port = socket->peer_name(name,sizeof(name)-1);
            if (port>=0)
            {
                peerBuf.append(name);
                if (port)
                    peerBuf.append(':').append(port);
                peerName.set(peerBuf);
            }
            else
            {
                /* There's a possibility the socket closed before got here, in which case, peer name is unavailable
                 * May potentially be unavailable for other reasons also.
                 * Must be set, as used in client stats HT.
                 * If socket closed, the handler will start up but notice closed and quit
                 */
                peerName.set("UNKNOWN PEER NAME");
            }
            {
                CriticalBlock block(ClientCountSect);
                if (++ClientCount>MaxClientCount)
                    MaxClientCount = ClientCount;
                if (TF_TRACE_CLIENT_CONN)
                {
                    StringBuffer s;
                    s.appendf("Connecting(%p) [%d,%d] to ",this,ClientCount,MaxClientCount);
                    s.append(peerName);
                    PROGLOG("%s", s.str());
                }
            }
            parent = _parent;
            left = 0;
            msg.setEndian(__BIG_ENDIAN);
            selecthandled = false;
            touch();
        }
        ~CRemoteClientHandler()
        {
            {
                CriticalBlock block(ClientCountSect);
                ClientCount--;
                if (TF_TRACE_CLIENT_CONN) {
                    PROGLOG("Disconnecting(%p) [%d,%d] ",this,ClientCount,MaxClientCount);
                }
            }
            ISocket *sock = socket.getClear();
            try {
                sock->Release();
            }
            catch (IException *e) {
                EXCLOG(e,"~CRemoteClientHandler");
                e->Release();
            }
        }
        bool notifySelected(ISocket *sock,unsigned selected)
        {
            if (TF_TRACE_FULL)
                PROGLOG("notifySelected(%p)",this);
            if (sock!=socket)
                WARNLOG("notifySelected - invalid socket passed");
            size32_t avail = (size32_t)socket->avail_read();
            if (avail)
                touch();
            if (left==0)
            {
                try
                {
                    left = avail?receiveBufferSize(socket):0;
                }
                catch (IException *e)
                {
                    EXCLOG(e,"notifySelected(1)");
                    e->Release();
                    left = 0;
                }
                if (left)
                {
                    avail = (size32_t)socket->avail_read();
                    try
                    {
                        msg.ensureCapacity(left);
                    }
                    catch (IException *e)
                    {
                        EXCLOG(e,"notifySelected(2)");
                        e->Release();
                        left = 0;
                        // if too big then corrupted packet so read avail to try and consume
                        char fbuf[1024];
                        while (avail)
                        {
                            size32_t rd = avail>sizeof(fbuf)?sizeof(fbuf):avail;
                            try
                            {
                                socket->read(fbuf, rd); // don't need timeout here
                                avail -= rd;
                            }
                            catch (IException *e)
                            {
                                EXCLOG(e,"notifySelected(2) flush");
                                e->Release();
                                break;
                            }
                        }
                        avail = 0;
                        left = 0;
                    }
                }
            }
            size32_t toread = left>avail?avail:left;
            if (toread)
            {
                try
                {
                    socket->read(msg.reserve(toread), toread);  // don't need timeout here
                }
                catch (IException *e)
                {
                    EXCLOG(e,"notifySelected(3)");
                    e->Release();
                    toread = left;
                    msg.clear();
                }
            }
            if (TF_TRACE_FULL)
                PROGLOG("notifySelected %d,%d",toread,left);
            if ((left!=0)&&(avail==0))
            {
                WARNLOG("notifySelected: Closing mid packet, %d remaining", left);
                toread = left;
                msg.clear();
            }
            left -= toread;
            if (left==0)
            {
                // DEBUG
                parent->notify(this, msg); // consumes msg
            }
            return false;
        }

        void logPrevHandle()
        {
            if (previdx<openFiles.ordinality())
            {
                const OpenFileInfo &fileInfo = openFiles.item(previdx);
                PROGLOG("Previous handle(%d): %s", fileInfo.handle, fileInfo.filename->text.get());
            }
        }

        bool throttleCommand(MemoryBuffer &msg)
        {
            RemoteFileCommandType cmd = RFCunknown;
            Owned<IException> e;
            try
            {
                msg.read(cmd);
                parent->throttleCommand(cmd, msg, this);
                return true;
            }
            catch (IException *_e)
            {
                e.setown(_e);
            }
            /* processCommand() will handle most exception and replies,
             * but if throttleCommand fails before it gets that far, this will handle
             */
            MemoryBuffer reply;
            initSendBuffer(reply);
            unsigned err = (cmd == RFCopenIO) ? RFSERR_OpenFailed : 0;
            parent->formatException(reply, e, cmd, false, err, this);
            sendBuffer(socket, reply);
            return false;
        }

        void processCommand(RemoteFileCommandType cmd, MemoryBuffer &msg, CThrottler *throttler)
        {
            MemoryBuffer reply;
            bool testSocketFlag = parent->processCommand(cmd, msg, initSendBuffer(reply), this, throttler);
            sendBuffer(socket, reply, testSocketFlag);
        }

        bool immediateCommand() // returns false if socket closed or failure
        {
            MemoryBuffer msg;
            msg.setEndian(__BIG_ENDIAN);
            touch();
            size32_t avail = (size32_t)socket->avail_read();
            if (avail==0)
                return false;
            receiveBuffer(socket, msg, 5);   // shouldn't timeout as data is available
            touch();
            if (msg.length()==0)
                return false;
            return throttleCommand(msg);
        }

        void process(MemoryBuffer &msg)
        {
            if (selecthandled)
                throttleCommand(msg);
            else
            {
                // msg only used/filled if process() has been triggered by notify()
                while (parent->threadRunningCount()<=parent->targetActiveThreads) // if too many threads add to select handler
                {
                    int w;
                    try
                    {
                        w = socket->wait_read(1000);
                    }
                    catch (IException *e)
                    {
                        EXCLOG(e, "CRemoteClientHandler::main wait_read error");
                        e->Release();
                        parent->onCloseSocket(this,1);
                        return;
                    }
                    if (w==0)
                        break;
                    if ((w<0)||!immediateCommand())
                    {
                        if (w<0)
                            WARNLOG("CRemoteClientHandler::main wait_read error");
                        parent->onCloseSocket(this,1);
                        return;
                    }
                }

                /* This is a bit confusing..
                 * The addClient below, adds this request to a selecthandler handled by another thread
                 * and passes ownership of 'this' (CRemoteClientHandler)
                 *
                 * When notified, the selecthandler will launch a new pool thread to handle the request
                 * If the pool thread limit is hit, the selecthandler will be blocked [ see comment in CRemoteFileServer::notify() ]
                 *
                 * Either way, a thread pool slot is occupied when processing a request.
                 * Blocked threads, will be blocked for up to 1 minute (as defined by createThreadPool call)
                 * IOW, if there are lots of incoming clients that can't be serviced by the CThrottler limit,
                 * a large number of pool threads will build up after a while.
                 *
                 * The CThrottler mechanism, imposes a further hard limit on how many concurrent request threads can be active.
                 * If the thread pool had an absolute limit (instead of just introducing a delay), then I don't see the point
                 * in this additional layer of throttling..
                 */
                selecthandled = true;
                parent->addClient(this);    // add to select handler
                // NB: this (CRemoteClientHandler) is now linked by the selecthandler and owned by the 'clients' list
            }
        }

        bool timedOut()
        {
            return (msTick()-lasttick)>CLIENT_TIMEOUT;
        }

        bool inactiveTimedOut()
        {
            unsigned ms = msTick();
            if ((ms-lastInactiveTick)>CLIENT_INACTIVEWARNING_TIMEOUT)
            {
                lastInactiveTick = ms;
                return true;
            }
            return false;
        }

        void touch()
        {
            lastInactiveTick = lasttick = msTick();
            atomic_set(&globallasttick,lasttick);
        }

        const char *queryPeerName()
        {
            return peerName;
        }

        bool getInfo(StringBuffer &str)
        {
            str.append("client(");
            const char *name = queryPeerName();
            bool ok;
            if (name)
            {
                ok = true;
                str.append(name);
            }
            else
                ok = false;
            unsigned ms = msTick();
            str.appendf("): last touch %d ms ago (%d, %d)",ms-lasttick,lasttick,ms);
            ForEachItemIn(i, openFiles)
            {
                const OpenFileInfo &fileInfo = openFiles.item(i);
                str.appendf("\n  %d: ", fileInfo.handle);
                str.append(fileInfo.filename->text.get());
            }
            return ok;
        }
    };

    class CThrottleQueueItem : public CSimpleInterface
    {
    public:
        RemoteFileCommandType cmd;
        Linked<CRemoteClientHandler> client;
        MemoryBuffer msg;
        CCycleTimer timer;
        CThrottleQueueItem(RemoteFileCommandType _cmd, MemoryBuffer &_msg, CRemoteClientHandler *_client) : cmd(_cmd), client(_client)
        {
            msg.swapWith(_msg);
        }
    };

    class CThrottler
    {
        Semaphore sem;
        CriticalSection crit, configureCrit;
        StringAttr title;
        unsigned limit, delayMs, cpuThreshold, queueLimit;
        unsigned disabledLimit;
        unsigned __int64 totalThrottleDelay;
        CCycleTimer totalThrottleDelayTimer;
        QueueOf<CThrottleQueueItem, false> queue;
        unsigned statsIntervalSecs;

    public:
        CThrottler(const char *_title) : title(_title)
        {
            totalThrottleDelay = 0;
            limit = 0;
            delayMs = DEFAULT_STDCMD_THROTTLEDELAYMS;
            cpuThreshold = DEFAULT_STDCMD_THROTTLECPULIMIT;
            disabledLimit = 0;
            queueLimit = DEFAULT_STDCMD_THROTTLEQUEUELIMIT;
            statsIntervalSecs = DEFAULT_STDCMD_THROTTLECPULIMIT;
        }
        ~CThrottler()
        {
            for (;;)
            {
                Owned<CThrottleQueueItem> item = queue.dequeue();
                if (!item)
                    break;
            }
        }
        unsigned queryLimit() const { return limit; }
        unsigned queryDelayMs() const { return delayMs; };;
        unsigned queryCpuThreshold() const { return cpuThreshold; }
        unsigned queryQueueLimit() const { return queueLimit; }
        StringBuffer &getInfoSummary(StringBuffer &info)
        {
            info.appendf("Throttler(%s) - limit=%u, delayMs=%u, cpuThreshold=%u, queueLimit=%u", title.get(), limit, delayMs, cpuThreshold, queueLimit).newline();
            unsigned elapsedSecs = totalThrottleDelayTimer.elapsedMs()/1000;
            time_t simple;
            time(&simple);
            simple -= elapsedSecs;

            CDateTime dt;
            dt.set(simple);
            StringBuffer dateStr;
            dt.getTimeString(dateStr, true);
            info.appendf("Throttler(%s): statistics since %s", title.get(), dateStr.str()).newline();
            info.appendf("Total delay of %0.2f seconds", ((double)totalThrottleDelay)/1000).newline();
            info.appendf("Requests currently queued: %u", queue.ordinality());
            return info;
        }
        void getInfo(StringBuffer &info)
        {
            CriticalBlock b(crit);
            getInfoSummary(info).newline();
        }
        void configure(unsigned _limit, unsigned _delayMs, unsigned _cpuThreshold, unsigned _queueLimit)
        {
            if (_limit > THROTTLE_MAX_LIMIT || _delayMs > THROTTLE_MAX_DELAYMS || _cpuThreshold > THROTTLE_MAX_CPUTHRESHOLD || _queueLimit > THROTTLE_MAX_QUEUELIMIT)
                throw MakeStringException(0, "Throttler(%s), rejecting configure command: limit=%u (max permitted=%u), delayMs=%u (max permitted=%u), cpuThreshold=%u (max permitted=%u), queueLimit=%u (max permitted=%u)",
                                              title.str(), _limit, THROTTLE_MAX_LIMIT, _delayMs, THROTTLE_MAX_DELAYMS, _cpuThreshold,
                                              THROTTLE_MAX_CPUTHRESHOLD, _queueLimit, THROTTLE_MAX_QUEUELIMIT);
            CriticalBlock b(configureCrit);
            int delta = 0;
            if (_limit)
            {
                if (disabledLimit) // if transitioning from disabled to some throttling
                {
                    assertex(0 == limit);
                    delta = _limit - disabledLimit; // + or -
                    disabledLimit = 0;
                }
                else
                    delta = _limit - limit; // + or -
            }
            else if (0 == disabledLimit)
            {
                PROGLOG("Throttler(%s): disabled, previous limit: %u", title.get(), limit);
                /* disabling - set limit immediately to let all new transaction through.
                 * NB: the semaphore signals are not consumed in this case, because transactions could be waiting on it.
                 * Instead the existing 'limit' is kept in 'disabledLimit', so that if/when throttling is
                 * re-enabled, it is used as a basis for increasing or consuming the semaphore signal count.
                 */
                disabledLimit = limit;
                limit = 0;
            }
            if (delta > 0)
            {
                PROGLOG("Throttler(%s): Increasing limit from %u to %u", title.get(), limit, _limit);
                sem.signal(delta);
                limit = _limit;
                // NB: If throttling was off, this doesn't effect transactions in progress, i.e. will only throttle new transactions coming in.
            }
            else if (delta < 0)
            {
                PROGLOG("Throttler(%s): Reducing limit from %u to %u", title.get(), limit, _limit);
                // NB: This is not expected to take long
                CCycleTimer timer;
                while (delta < 0)
                {
                    if (sem.wait(1000))
                        ++delta;
                    else
                        PROGLOG("Throttler(%s): Waited %0.2f seconds so far for up to a maximum of %u (previous limit) transactions to complete, %u completed", title.get(), ((double)timer.elapsedMs())/1000, limit, -delta);
                }
                limit = _limit;
                // NB: doesn't include transactions in progress, i.e. will only throttle new transactions coming in.
            }
            if (_delayMs != delayMs)
            {
                PROGLOG("Throttler(%s): New delayMs=%u, previous: %u", title.get(), _delayMs, delayMs);
                delayMs = _delayMs;
            }
            if (_cpuThreshold != cpuThreshold)
            {
                PROGLOG("Throttler(%s): New cpuThreshold=%u, previous: %u", title.get(), _cpuThreshold, cpuThreshold);
                cpuThreshold = _cpuThreshold;
            }
            if (((unsigned)-1) != _queueLimit && _queueLimit != queueLimit)
            {
                PROGLOG("Throttler(%s): New queueLimit=%u%s, previous: %u", title.get(), _queueLimit, 0==_queueLimit?"(disabled)":"", queueLimit);
                queueLimit = _queueLimit;
            }
        }
        void setStatsInterval(unsigned _statsIntervalSecs)
        {
            if (_statsIntervalSecs != statsIntervalSecs)
            {
                PROGLOG("Throttler(%s): New statsIntervalSecs=%u, previous: %u", title.get(), _statsIntervalSecs, statsIntervalSecs);
                statsIntervalSecs = _statsIntervalSecs;
            }
        }
        void take(RemoteFileCommandType cmd) // cmd for info. only
        {
            for (;;)
            {
                if (sem.wait(delayMs))
                    return;
                PROGLOG("Throttler(%s): transaction delayed [cmd=%s]", title.get(), getRFCText(cmd));
            }
        }
        void release()
        {
            sem.signal();
        }
        StringBuffer &getStats(StringBuffer &stats, bool reset)
        {
            CriticalBlock b(crit);
            getInfoSummary(stats);
            if (reset)
            {
                totalThrottleDelayTimer.reset();
                totalThrottleDelay = 0;
            }
            return stats;
        }
        void addCommand(RemoteFileCommandType cmd, MemoryBuffer &msg, CRemoteClientHandler *client)
        {
            CCycleTimer timer;
            Owned<IException> exception;
            bool hadSem = true;
            if (!sem.wait(delayMs))
            {
                CriticalBlock b(crit);
                if (!sem.wait(0)) // check hasn't become available
                {
                    unsigned cpu = getLatestCPUUsage();
                    if (getLatestCPUUsage()<cpuThreshold)
                    {
                        /* Allow to proceed, despite hitting throttle limit because CPU < threshold
                         * NB: The overall number of threads is still capped by the thread pool.
                         */
                        unsigned ms = timer.elapsedMs();
                        totalThrottleDelay += ms;
                        PROGLOG("Throttler(%s): transaction delayed [cmd=%s] for : %u milliseconds, proceeding as cpu(%u)<throttleCPULimit(%u)", title.get(), getRFCText(cmd), cpu, ms, cpuThreshold);
                        hadSem = false;
                    }
                    else
                    {
                        if (queueLimit && queue.ordinality()>=queueLimit)
                            throw MakeStringException(0, "Throttler(%s), the maxiumum number of items are queued (%u), rejecting new command[%s]", title.str(), queue.ordinality(), getRFCText(cmd));
                        queue.enqueue(new CThrottleQueueItem(cmd, msg, client)); // NB: takes over ownership of 'client' from running thread
                        PROGLOG("Throttler(%s): transaction delayed [cmd=%s], queuing (%u queueud), [client=%p, sock=%u]", title.get(), getRFCText(cmd), queue.ordinality(), client, client->socket->OShandle());
                        return;
                    }
                }
            }

            /* Guarantee that sem is released.
             * Should normally release on clean exit when queue is empty.
             */
            struct ReleaseSem
            {
                Semaphore *sem;
                ReleaseSem(Semaphore *_sem) { sem = _sem; }
                ~ReleaseSem() { if (sem) sem->signal(); }
            } releaseSem(hadSem?&sem:NULL);

            /* Whilst holding on this throttle slot (i.e. before signalling semaphore back), process
             * queued items. NB: other threads that are finishing will do also.
             * Queued items are processed 1st, then the current request, then anything that was queued when handling current request
             * Throttle slot (semaphore) is only given back when no more to do.
             */
            Linked<CRemoteClientHandler> currentClient;
            MemoryBuffer currentMsg;
            unsigned ms;
            for (;;)
            {
                RemoteFileCommandType currentCmd;
                {
                    CriticalBlock b(crit);
                    Owned<CThrottleQueueItem> item = queue.dequeue();
                    if (item)
                    {
                        currentCmd = item->cmd;
                        currentClient.setown(item->client.getClear());
                        currentMsg.swapWith(item->msg);
                        ms = item->timer.elapsedMs();
                    }
                    else
                    {
                        if (NULL == client) // previously handled and queue empty
                        {
                            /* Commands are only queued if semaphore is exhaused (checked inside crit)
                             * so only signal the semaphore inside the crit, after checking if there are no queued items
                             */
                            if (hadSem)
                            {
                                releaseSem.sem = NULL;
                                sem.signal();
                            }
                            break;
                        }
                        currentCmd = cmd;
                        currentClient.set(client); // process current request after dealing with queue
                        currentMsg.swapWith(msg);
                        ms = timer.elapsedMs();
                        client = NULL;
                    }
                }
                if (ms >= 1000)
                {
                    if (ms>delayMs)
                        PROGLOG("Throttler(%s): transaction delayed [cmd=%s] for : %u seconds", title.get(), getRFCText(currentCmd), ms/1000);
                }
                {
                    CriticalBlock b(crit);
                    totalThrottleDelay += ms;
                }
                try
                {
                    currentClient->processCommand(currentCmd, currentMsg, this);
                }
                catch (IException *e)
                {
                    EXCLOG(e, "addCommand: processCommand failed");
                    e->Release();
                }
            }
        }
    };

    // temporarily release a throttler slot
    class CThrottleReleaseBlock
    {
        CThrottler &throttler;
        RemoteFileCommandType cmd;
    public:
        CThrottleReleaseBlock(CThrottler &_throttler, RemoteFileCommandType _cmd) : throttler(_throttler), cmd(_cmd)
        {
            throttler.release();
        }
        ~CThrottleReleaseBlock()
        {
            throttler.take(cmd);
        }
    };

    int                 lasthandle;
    CriticalSection     sect;
    Owned<ISocket>      acceptsock;
    Owned<ISocket>      securesock;
    Owned<ISocketSelectHandler> selecthandler;
    Owned<IThreadPool>  threads;    // for commands
    bool stopping;
    unsigned clientcounttick;
    unsigned closedclients;
    CAsyncCommandManager asyncCommandManager;
    CThrottler stdCmdThrottler, slowCmdThrottler;
    CClientStatsTable clientStatsTable;
    atomic_t globallasttick;
    unsigned targetActiveThreads;
    bool authorizedOnly;
    Owned<IPropertyTree> keyPairInfo;

    int getNextHandle()
    {
        // called in sect critical block
        for (;;) {
            if (lasthandle==INT_MAX)
                lasthandle = 1;
            else
                lasthandle++;
            unsigned idx1;
            unsigned idx2;
            if (!findHandle(lasthandle,idx1,idx2))
                return lasthandle;
        }
    }

    bool findHandle(int handle,unsigned &clientidx,unsigned &handleidx)
    {
        // called in sect critical block
        clientidx = (unsigned)-1;
        handleidx = (unsigned)-1;
        ForEachItemIn(i,clients) {
            CRemoteClientHandler &client = clients.item(i);
            ForEachItemIn(j, client.openFiles)
            {
                if (client.openFiles.item(j).handle==handle)
                {
                    handleidx = j;
                    clientidx = i;
                    return true;
                }
            }
        }
        return false;
    }

    unsigned readKeyData(IKeyManager *keyManager, unsigned maxRecs, MemoryBuffer &reply, bool &maxHit)
    {
        DelayedSizeMarker keyDataSzReturned(reply);
        unsigned numRecs = 0;
        maxHit = false;
        unsigned pos = reply.length();
        while (keyManager->lookup(true))
        {
            unsigned size = keyManager->queryRowSize();
            const byte *result = keyManager->queryKeyBuffer();
            reply.append(size);
            reply.append(size, result);
            ++numRecs;
            if (maxRecs && (0 == --maxRecs))
            {
                maxHit = true;
                break;
            }
            if (reply.length()-pos >= MAX_KEYDATA_SZ)
            {
                maxHit = true;
                break;
            }
        }
        keyDataSzReturned.write();
        return numRecs;
    }

    class cCommandProcessor: public CInterface, implements IPooledThread
    {
        Owned<CRemoteClientHandler> client;
        MemoryBuffer msg;

    public:
        IMPLEMENT_IINTERFACE;

        struct cCommandProcessorParams
        {
            cCommandProcessorParams() { msg.setEndian(__BIG_ENDIAN); }
            CRemoteClientHandler *client;
            MemoryBuffer msg;
        };

        virtual void init(void *_params) override
        {
            cCommandProcessorParams &params = *(cCommandProcessorParams *)_params;
            client.setown(params.client);
            msg.swapWith(params.msg);
        }

        virtual void threadmain() override
        {
            // idea is that initially we process commands inline then pass over to select handler
            try
            {
                client->process(msg);
            }
            catch (IException *e)
            {
                // suppress some errors
                EXCLOG(e,"cCommandProcessor::threadmain");
                e->Release();
            }
            try
            {
                client.clear();
            }
            catch (IException *e)
            {
                // suppress some more errors clearing client
                EXCLOG(e,"cCommandProcessor::threadmain(2)");
                e->Release();
            }
        }
        virtual bool stop() override
        {
            return true;
        }
        virtual bool canReuse() const override
        {
            return false; // want to free owned socket
        }
    };

    IArrayOf<CRemoteClientHandler> clients;

    class cImpersonateBlock
    {
        CRemoteClientHandler &client;
    public:
        cImpersonateBlock(CRemoteClientHandler &_client)
            : client(_client)
        {
            if (client.user.get()) {
                if (TF_TRACE)
                    PROGLOG("Impersonate user: %s",client.user->username());
                client.user->impersonate();
            }
        }
        ~cImpersonateBlock()
        {
            if (client.user.get()) {
                if (TF_TRACE)
                    PROGLOG("Stop impersonating user: %s",client.user->username());
                client.user->revert();
            }
        }
    };

#define IMPERSONATE_USER(client) cImpersonateBlock ublock(client)

    bool handleFull(MemoryBuffer &inMb, size32_t inPos, MemoryBuffer &compressMb, ICompressor *compressor, size32_t replyLimit, size32_t &totalSz)
    {
        size32_t sz = inMb.length()-inPos;
        if (sz < replyLimit)
            return false;

        if (!compressor)
            return true;

        // consumes data from inMb into compressor
        totalSz += sz;
        const void *data = inMb.bytes()+inPos;
        assertex(compressor->write(data, sz) == sz);
        inMb.setLength(inPos);
        return compressMb.capacity() > replyLimit;
    }
public:

    IMPLEMENT_IINTERFACE

    CRemoteFileServer(unsigned maxThreads, unsigned maxThreadsDelayMs, unsigned maxAsyncCopy, bool _authorizedOnly, IPropertyTree *_keyPairInfo)
        : asyncCommandManager(maxAsyncCopy), stdCmdThrottler("stdCmdThrotlter"), slowCmdThrottler("slowCmdThrotlter"), authorizedOnly(_authorizedOnly), keyPairInfo(_keyPairInfo)
    {
        lasthandle = 0;
        selecthandler.setown(createSocketSelectHandler(NULL));

        stdCmdThrottler.configure(DEFAULT_STDCMD_PARALLELREQUESTLIMIT, DEFAULT_STDCMD_THROTTLEDELAYMS, DEFAULT_STDCMD_THROTTLECPULIMIT, DEFAULT_STDCMD_THROTTLEQUEUELIMIT);
        slowCmdThrottler.configure(DEFAULT_SLOWCMD_PARALLELREQUESTLIMIT, DEFAULT_SLOWCMD_THROTTLEDELAYMS, DEFAULT_SLOWCMD_THROTTLECPULIMIT, DEFAULT_SLOWCMD_THROTTLEQUEUELIMIT);

        unsigned targetMinThreads=maxThreads*20/100; // 20%
        if (0 == targetMinThreads) targetMinThreads = 1;
        targetActiveThreads=maxThreads*80/100; // 80%
        if (0 == targetActiveThreads) targetActiveThreads = 1;

        class CCommandFactory : public CSimpleInterfaceOf<IThreadFactory>
        {
            CRemoteFileServer &parent;
        public:
            CCommandFactory(CRemoteFileServer &_parent) : parent(_parent) { }
            virtual IPooledThread *createNew()
            {
                return parent.createCommandProcessor();
            }
        };
        Owned<IThreadFactory> factory = new CCommandFactory(*this); // NB: pool links factory, so takes ownership
        threads.setown(createThreadPool("CRemoteFileServerPool", factory, NULL, maxThreads, maxThreadsDelayMs,
#ifdef __64BIT__
            0, // Unlimited stack size
#else
            0x10000,
#endif
        INFINITE,targetMinThreads));
        threads->setStartDelayTracing(60); // trace amount delayed every minute.

        PROGLOG("CRemoteFileServer: maxThreads = %u, maxThreadsDelayMs = %u, maxAsyncCopy = %u", maxThreads, maxThreadsDelayMs, maxAsyncCopy);

        stopping = false;
        clientcounttick = msTick();
        closedclients = 0;
        atomic_set(&globallasttick,msTick());
    }

    ~CRemoteFileServer()
    {
#ifdef _DEBUG
        PROGLOG("Exiting CRemoteFileServer");
#endif
        asyncCommandManager.join();
        clients.kill();
#ifdef _DEBUG
        PROGLOG("Exited CRemoteFileServer");
#endif
    }
    bool lookupFileIOHandle(int handle, OpenFileInfo &fileInfo, unsigned newFlags=0)
    {
        if (handle<=0)
            return false;
        CriticalBlock block(sect);
        unsigned clientidx;
        unsigned handleidx;
        if (!findHandle(handle,clientidx,handleidx))
            return false;
        CRemoteClientHandler &client = clients.item(clientidx);
        OpenFileInfo &openFileInfo = client.openFiles.element(handleidx); // NB: links members
        openFileInfo.flags |= newFlags;
        fileInfo = openFileInfo;
        client.previdx = handleidx;
        return true;
    }

    //MORE: The file handles should timeout after a while, and accessing an old (invalid handle)
    // should throw a different exception
    bool checkFileIOHandle(int handle, IFileIO *&fileio, bool del=false)
    {
        fileio = NULL;
        if (handle<=0)
            return false;
        CriticalBlock block(sect);
        unsigned clientidx;
        unsigned handleidx;
        if (findHandle(handle,clientidx,handleidx))
        {
            CRemoteClientHandler &client = clients.item(clientidx);
            const OpenFileInfo &fileInfo = client.openFiles.item(handleidx);
            if (del)
            {
                if (fileInfo.flags & of_key)
                    clearKeyStoreCacheEntry(fileInfo.fileIO);
                client.openFiles.remove(handleidx);
                client.previdx = (unsigned)-1;
            }
            else
            {
               fileio = client.openFiles.item(handleidx).fileIO;
               client.previdx = handleidx;
            }
            return true;
        }
        return false;
    }

    void checkFileIOHandle(MemoryBuffer &reply, int handle, IFileIO *&fileio, bool del=false)
    {
        if (!checkFileIOHandle(handle, fileio, del))
            throw createDafsException(RFSERR_InvalidFileIOHandle, nullptr);
    }

    void onCloseSocket(CRemoteClientHandler *client, int which)
    {
        if (!client)
            return;
        CriticalBlock block(sect);
#ifdef _DEBUG
        StringBuffer s(client->queryPeerName());
        PROGLOG("onCloseSocket(%d) %s",which,s.str());
#endif
        if (client->socket)
        {
            try
            {
                /* JCSMORE - shouldn't this really be dependent on whether selecthandled=true
                 * It has not been added to the selecthandler
                 * Harmless, but wasteful if so.
                 */
                selecthandler->remove(client->socket);
            }
            catch (IException *e) {
                EXCLOG(e,"CRemoteFileServer::onCloseSocket.1");
                e->Release();
            }
        }
        try {
            clients.zap(*client);
        }
        catch (IException *e) {
            EXCLOG(e,"CRemoteFileServer::onCloseSocket.2");
            e->Release();
        }
    }


    bool cmdOpenFileIO(MemoryBuffer & msg, MemoryBuffer & reply, CRemoteClientHandler &client)
    {
        IMPERSONATE_USER(client);
        Owned<StringAttrItem> name = new StringAttrItem;
        byte mode;
        byte share;
        msg.read(name->text).read(mode).read(share);
        // also try to recv extra byte
        byte extra = 0;
        unsigned short sMode = IFUnone;
        unsigned short cFlags = IFUnone;
        if (msg.remaining() >= sizeof(byte))
        {
            msg.read(extra);
            // and then try to recv extra sMode, cFlags (always sent together)
            if (msg.remaining() >= (sizeof(sMode) + sizeof(cFlags)))
                msg.read(sMode).read(cFlags);
        }
        IFEflags extraFlags = (IFEflags)extra;
        // none => nocache for remote (hint)
        // can revert to previous behavior with conf file setting "allow_pgcache_flush=false"
        if (extraFlags == IFEnone)
            extraFlags = IFEnocache;
        Owned<IFile> file = createIFile(name->text);
        switch ((compatIFSHmode)share) {
        case compatIFSHnone:
            file->setCreateFlags(S_IRUSR|S_IWUSR);
            file->setShareMode(IFSHnone);
            break;
        case compatIFSHread:
            file->setShareMode(IFSHread);
            break;
        case compatIFSHwrite:
            file->setShareMode(IFSHfull);
            break;
        case compatIFSHexec:
            file->setCreateFlags(S_IRUSR|S_IWUSR|S_IXUSR|S_IRGRP|S_IXGRP|S_IROTH|S_IXOTH);
            break;
        case compatIFSHall:
            file->setCreateFlags(S_IRUSR|S_IWUSR|S_IRGRP|S_IWGRP|S_IROTH|S_IWOTH); // bit excessive
            file->setShareMode(IFSHfull);
            break;
        }
        // use sMode, cFlags if sent
        if (sMode != IFUnone && cFlags != IFUnone)
        {
            file->setCreateFlags(cFlags);
            file->setShareMode((IFSHmode)sMode);
        }
        if (TF_TRACE_PRE_IO)
            PROGLOG("before open file '%s',  (%d,%d,%d,%d,0%o)",name->text.get(),(int)mode,(int)share,extraFlags,sMode,cFlags);
        Owned<IFileIO> fileio = file->open((IFOmode)mode,extraFlags);
        int handle;
        if (fileio)
        {
            CriticalBlock block(sect);
            handle = getNextHandle();
            client.previdx = client.openFiles.ordinality();
            client.openFiles.append(OpenFileInfo(handle, fileio, name));
        }
        else
            handle = 0;
        reply.append(RFEnoerror);
        reply.append(handle);
        if (TF_TRACE)
            PROGLOG("open file '%s',  (%d,%d) handle = %d",name->text.get(),(int)mode,(int)share,handle);
        return true;
    }

    bool cmdCloseFileIO(MemoryBuffer & msg, MemoryBuffer & reply)
    {
        int handle;
        msg.read(handle);
        IFileIO *fileio;
        checkFileIOHandle(reply, handle, fileio, true);
        if (TF_TRACE)
            PROGLOG("close file,  handle = %d",handle);
        reply.append(RFEnoerror);
        return true;
    }

    void cmdRead(MemoryBuffer & msg, MemoryBuffer & reply, CClientStats &stats)
    {
        int handle;
        __int64 pos;
        size32_t len;
        msg.read(handle).read(pos).read(len);
        IFileIO *fileio;
        checkFileIOHandle(reply, handle, fileio);

        //arrange it so we read directly into the reply buffer...
        unsigned posOfErr = reply.length();
        reply.append((unsigned)RFEnoerror);
        size32_t numRead;
        unsigned posOfLength = reply.length();
        if (TF_TRACE_PRE_IO)
            PROGLOG("before read file,  handle = %d, toread = %d",handle,len);
        reply.reserve(sizeof(numRead));
        void *data = reply.reserve(len);
        numRead = fileio->read(pos,len,data);
        stats.addRead(len);
        if (TF_TRACE)
            PROGLOG("read file,  handle = %d, pos = %" I64F "d, toread = %d, read = %d",handle,pos,len,numRead);
        reply.setLength(posOfLength + sizeof(numRead) + numRead);
        reply.writeEndianDirect(posOfLength,sizeof(numRead),&numRead);
    }

    void cmdSize(MemoryBuffer & msg, MemoryBuffer & reply)
    {
        int handle;
        msg.read(handle);
        IFileIO *fileio;
        checkFileIOHandle(reply, handle, fileio);
        __int64 size = fileio->size();
        reply.append((unsigned)RFEnoerror).append(size);
        if (TF_TRACE)
            PROGLOG("size file,  handle = %d, size = %" I64F "d",handle,size);
    }

    void cmdSetSize(MemoryBuffer & msg, MemoryBuffer & reply)
    {
        int handle;
        offset_t size;
        msg.read(handle).read(size);
        IFileIO *fileio;
        if (TF_TRACE)
            PROGLOG("set size file,  handle = %d, size = %" I64F "d",handle,size);
        checkFileIOHandle(reply, handle, fileio);
        fileio->setSize(size);
        reply.append((unsigned)RFEnoerror);
    }

    void cmdWrite(MemoryBuffer & msg, MemoryBuffer & reply, CClientStats &stats)
    {
        int handle;
        __int64 pos;
        size32_t len;
        msg.read(handle).read(pos).read(len);
        IFileIO *fileio;
        checkFileIOHandle(reply, handle, fileio);
        const byte *data = (const byte *)msg.readDirect(len);
        if (TF_TRACE_PRE_IO)
            PROGLOG("before write file,  handle = %d, towrite = %d",handle,len);
        size32_t numWritten = fileio->write(pos,len,data);
        stats.addWrite(numWritten);
        if (TF_TRACE)
            PROGLOG("write file,  handle = %d, towrite = %d, written = %d",handle,len,numWritten);
        reply.append((unsigned)RFEnoerror).append(numWritten);
    }

    void cmdExists(MemoryBuffer & msg, MemoryBuffer & reply, CRemoteClientHandler &client)
    {
        IMPERSONATE_USER(client);
        StringAttr name;
        msg.read(name);
        if (TF_TRACE)
            PROGLOG("exists,  '%s'",name.get());
        Owned<IFile> file=createIFile(name);
        bool e = file->exists();
        reply.append((unsigned)RFEnoerror).append(e);
    }

    void cmdRemove(MemoryBuffer & msg, MemoryBuffer & reply,CRemoteClientHandler &client)
    {
        IMPERSONATE_USER(client);
        StringAttr name;
        msg.read(name);
        if (TF_TRACE)
            PROGLOG("remove,  '%s'",name.get());
        Owned<IFile> file=createIFile(name);
        bool e = file->remove();
        reply.append((unsigned)RFEnoerror).append(e);
    }

    void cmdGetVer(MemoryBuffer & msg, MemoryBuffer & reply)
    {
        if (TF_TRACE)
            PROGLOG("getVer");
        if (msg.getPos()+sizeof(unsigned)>msg.length())
            reply.append((unsigned)RFEnoerror);
        else
            reply.append((unsigned)FILESRV_VERSION+0x10000);
        reply.append(VERSTRING);
    }

    void cmdRename(MemoryBuffer & msg, MemoryBuffer & reply,CRemoteClientHandler &client)
    {
        IMPERSONATE_USER(client);
        StringAttr fromname;
        msg.read(fromname);
        StringAttr toname;
        msg.read(toname);
        if (TF_TRACE)
            PROGLOG("rename,  '%s' to '%s'",fromname.get(),toname.get());
        Owned<IFile> file=createIFile(fromname);
        file->rename(toname);
        reply.append((unsigned)RFEnoerror);
    }

    void cmdMove(MemoryBuffer & msg, MemoryBuffer & reply,CRemoteClientHandler &client)
    {
        IMPERSONATE_USER(client);
        StringAttr fromname;
        msg.read(fromname);
        StringAttr toname;
        msg.read(toname);
        if (TF_TRACE)
            PROGLOG("move,  '%s' to '%s'",fromname.get(),toname.get());
        Owned<IFile> file=createIFile(fromname);
        file->move(toname);
        reply.append((unsigned)RFEnoerror);
    }

    void cmdCopy(MemoryBuffer & msg, MemoryBuffer & reply, CRemoteClientHandler &client)
    {
        IMPERSONATE_USER(client);
        StringAttr fromname;
        msg.read(fromname);
        StringAttr toname;
        msg.read(toname);
        if (TF_TRACE)
            PROGLOG("copy,  '%s' to '%s'",fromname.get(),toname.get());
        copyFile(toname, fromname);
        reply.append((unsigned)RFEnoerror);
    }

    void cmdAppend(MemoryBuffer & msg, MemoryBuffer & reply, CRemoteClientHandler &client, CClientStats &stats)
    {
        IMPERSONATE_USER(client);
        int handle;
        __int64 pos;
        __int64 len;
        StringAttr srcname;
        msg.read(handle).read(srcname).read(pos).read(len);
        IFileIO *fileio;
        checkFileIOHandle(reply, handle, fileio);

        Owned<IFile> file = createIFile(srcname.get());
        __int64 written = fileio->appendFile(file,pos,len);
        stats.addWrite(written);
        if (TF_TRACE)
            PROGLOG("append file,  handle = %d, file=%s, pos = %" I64F "d len = %" I64F "d written = %" I64F "d",handle,srcname.get(),pos,len,written);
        reply.append((unsigned)RFEnoerror).append(written);
    }

    void cmdIsFile(MemoryBuffer &msg, MemoryBuffer &reply, CRemoteClientHandler &client)
    {
        IMPERSONATE_USER(client);
        StringAttr name;
        msg.read(name);
        if (TF_TRACE)
            PROGLOG("isFile,  '%s'",name.get());
        Owned<IFile> file=createIFile(name);
        unsigned ret = (unsigned)file->isFile();
        reply.append((unsigned)RFEnoerror).append(ret);
    }

    void cmdIsDir(MemoryBuffer &msg, MemoryBuffer &reply, CRemoteClientHandler &client)
    {
        IMPERSONATE_USER(client);
        StringAttr name;
        msg.read(name);
        if (TF_TRACE)
            PROGLOG("isDir,  '%s'",name.get());
        Owned<IFile> file=createIFile(name);
        unsigned ret = (unsigned)file->isDirectory();
        reply.append((unsigned)RFEnoerror).append(ret);
    }

    void cmdIsReadOnly(MemoryBuffer &msg, MemoryBuffer &reply, CRemoteClientHandler &client)
    {
        IMPERSONATE_USER(client);
        StringAttr name;
        msg.read(name);
        if (TF_TRACE)
            PROGLOG("isReadOnly,  '%s'",name.get());
        Owned<IFile> file=createIFile(name);
        unsigned ret = (unsigned)file->isReadOnly();
        reply.append((unsigned)RFEnoerror).append(ret);
    }

    void cmdSetReadOnly(MemoryBuffer &msg, MemoryBuffer &reply, CRemoteClientHandler &client)
    {
        IMPERSONATE_USER(client);
        StringAttr name;
        bool set;
        msg.read(name).read(set);

        if (TF_TRACE)
            PROGLOG("setReadOnly,  '%s' %d",name.get(),(int)set);
        Owned<IFile> file=createIFile(name);
        file->setReadOnly(set);
        reply.append((unsigned)RFEnoerror);
    }

    void cmdSetFilePerms(MemoryBuffer &msg, MemoryBuffer &reply, CRemoteClientHandler &client)
    {
        IMPERSONATE_USER(client);
        StringAttr name;
        unsigned fPerms;
        msg.read(name).read(fPerms);
        if (TF_TRACE)
            PROGLOG("setFilePerms,  '%s' 0%o",name.get(),fPerms);
        Owned<IFile> file=createIFile(name);
        file->setFilePermissions(fPerms);
        reply.append((unsigned)RFEnoerror);
    }

    void cmdGetTime(MemoryBuffer &msg, MemoryBuffer &reply, CRemoteClientHandler &client)
    {
        IMPERSONATE_USER(client);
        StringAttr name;
        msg.read(name);
        if (TF_TRACE)
            PROGLOG("getTime,  '%s'",name.get());
        Owned<IFile> file=createIFile(name);
        CDateTime createTime;
        CDateTime modifiedTime;
        CDateTime accessedTime;
        bool ret = file->getTime(&createTime,&modifiedTime,&accessedTime);
        reply.append((unsigned)RFEnoerror).append(ret);
        if (ret)
        {
            createTime.serialize(reply);
            modifiedTime.serialize(reply);
            accessedTime.serialize(reply);
        }
    }

    void cmdSetTime(MemoryBuffer &msg, MemoryBuffer &reply, CRemoteClientHandler &client)
    {
        IMPERSONATE_USER(client);
        StringAttr name;
        bool creategot;
        CDateTime createTime;
        bool modifiedgot;
        CDateTime modifiedTime;
        bool accessedgot;
        CDateTime accessedTime;
        msg.read(name);
        msg.read(creategot);
        if (creategot)
            createTime.deserialize(msg);
        msg.read(modifiedgot);
        if (modifiedgot)
            modifiedTime.deserialize(msg);
        msg.read(accessedgot);
        if (accessedgot)
            accessedTime.deserialize(msg);

        if (TF_TRACE)
            PROGLOG("setTime,  '%s'",name.get());
        Owned<IFile> file=createIFile(name);

        bool ret = file->setTime(creategot?&createTime:NULL,modifiedgot?&modifiedTime:NULL,accessedgot?&accessedTime:NULL);
        reply.append((unsigned)RFEnoerror).append(ret);
    }

    void cmdCreateDir(MemoryBuffer &msg, MemoryBuffer &reply, CRemoteClientHandler &client)
    {
        IMPERSONATE_USER(client);
        StringAttr name;
        msg.read(name);
        if (TF_TRACE)
            PROGLOG("CreateDir,  '%s'",name.get());
        Owned<IFile> dir=createIFile(name);
        bool ret = dir->createDirectory();
        reply.append((unsigned)RFEnoerror).append(ret);
    }

    void cmdGetDir(MemoryBuffer &msg, MemoryBuffer &reply, CRemoteClientHandler &client)
    {
        IMPERSONATE_USER(client);
        StringAttr name;
        StringAttr mask;
        bool includedir;
        bool sub;
        byte stream = 0;
        msg.read(name).read(mask).read(includedir).read(sub);
        if (msg.remaining()>=sizeof(byte))
        {
            msg.read(stream);
            if (stream==1)
                client.opendir.clear();
        }
        if (TF_TRACE)
            PROGLOG("GetDir,  '%s', '%s', stream='%u'",name.get(),mask.get(),stream);
        if (!stream && !containsFileWildcard(mask))
        {
            // if no streaming, and mask contains no wildcard, it is much more efficient to get the info without a directory iterator!
            StringBuffer fullFilename(name);
            addPathSepChar(fullFilename).append(mask);
            Owned<IFile> iFile = createIFile(fullFilename);

            // NB: This must preserve same serialization format as CRemoteDirectoryIterator::serialize produces for <=1 file.
            reply.append((unsigned)RFEnoerror);
            if (!iFile->exists())
                reply.append((byte)0);
            else
            {
                byte b=1;
                reply.append(b);
                bool isDir = foundYes == iFile->isDirectory();
                reply.append(isDir);
                reply.append(isDir ? 0 : iFile->size());
                CDateTime dt;
                iFile->getTime(nullptr, &dt, nullptr);
                dt.serialize(reply);
                reply.append(mask);
                b = 0;
                reply.append(b);
            }
        }
        else
        {
            Owned<IFile> dir=createIFile(name);

            Owned<IDirectoryIterator> iter;
            if (stream>1)
                iter.set(client.opendir);
            else
            {
                iter.setown(dir->directoryFiles(mask.length()?mask.get():NULL,sub,includedir));
                if (stream != 0)
                    client.opendir.set(iter);
            }
            if (!iter)
                throw createDafsException(RFSERR_GetDirFailed, nullptr);
            reply.append((unsigned)RFEnoerror);
            if (CRemoteDirectoryIterator::serialize(reply,iter,stream?0x100000:0,stream<2))
            {
                if (stream != 0)
                    client.opendir.clear();
            }
            else
            {
                bool cont=true;
                reply.append(cont);
            }
        }
    }

    void cmdMonitorDir(MemoryBuffer &msg, MemoryBuffer &reply, CRemoteClientHandler &client)
    {
        IMPERSONATE_USER(client);
        StringAttr name;
        StringAttr mask;
        bool includedir;
        bool sub;
        unsigned checkinterval;
        unsigned timeout;
        __int64 cancelid; // not yet used
        msg.read(name).read(mask).read(includedir).read(sub).read(checkinterval).read(timeout).read(cancelid);
        byte isprev;
        msg.read(isprev);
        Owned<IDirectoryIterator> prev;
        if (isprev==1)
        {
            SocketEndpoint ep;
            CRemoteDirectoryIterator *di = new CRemoteDirectoryIterator(ep,name);
            di->appendBuf(msg);
            prev.setown(di);
        }
        if (TF_TRACE)
            PROGLOG("MonitorDir,  '%s' '%s'",name.get(),mask.get());
        Owned<IFile> dir=createIFile(name);
        Owned<IDirectoryDifferenceIterator> iter=dir->monitorDirectory(prev,mask.length()?mask.get():NULL,sub,includedir,checkinterval,timeout);
        reply.append((unsigned)RFEnoerror);
        byte state = (iter.get()==NULL)?0:1;
        reply.append(state);
        if (state==1)
            CRemoteDirectoryIterator::serializeDiff(reply,iter);
    }

    void cmdCopySection(MemoryBuffer &msg, MemoryBuffer &reply, CRemoteClientHandler &client)
    {
        IMPERSONATE_USER(client);
        StringAttr uuid;
        StringAttr fromFile;
        StringAttr toFile;
        offset_t toOfs;
        offset_t fromOfs;
        offset_t size;
        offset_t sizeDone=0;
        offset_t totalSize=(offset_t)-1;
        unsigned timeout;
        msg.read(uuid).read(fromFile).read(toFile).read(toOfs).read(fromOfs).read(size).read(timeout);
        AsyncCommandStatus status = asyncCommandManager.copySection(uuid,fromFile,toFile,toOfs,fromOfs,size,sizeDone,totalSize,timeout);
        reply.append((unsigned)RFEnoerror).append((unsigned)status).append(sizeDone).append(totalSize);
    }

    static void treeCopyFile(RemoteFilename &srcfn, RemoteFilename &dstfn, const char *net, const char *mask, IpAddress &ip, bool usetmp, CThrottler *throttler, CFflags copyFlags=CFnone)
    {
        unsigned start = msTick();
        Owned<IFile> dstfile = createIFile(dstfn);
        // the following is really to check the dest node is up and working (otherwise not much point in continuing!)
        if (dstfile->exists())
            PROGLOG("TREECOPY overwriting '%s'",dstfile->queryFilename());
        Owned<IFile> srcfile = createIFile(srcfn);
        unsigned lastmin = 0;
        if (!srcfn.queryIP().ipequals(dstfn.queryIP())) {
            CriticalBlock block(treeCopyCrit);
            for (;;) {
                CDateTime dt;
                offset_t sz;
                try {
                    sz = srcfile->size();
                    if (sz==(offset_t)-1) {
                        if (TF_TRACE_TREE_COPY)
                            PROGLOG("TREECOPY source not found '%s'",srcfile->queryFilename());
                        break;
                    }
                    srcfile->getTime(NULL,&dt,NULL);
                }
                catch (IException *e) {
                    EXCLOG(e,"treeCopyFile(1)");
                    e->Release();
                    break;
                }
                Linked<CTreeCopyItem> tc;
                unsigned now = msTick();
                ForEachItemInRev(i1,treeCopyArray) {
                    CTreeCopyItem &item = treeCopyArray.item(i1);
                    // prune old entries (not strictly needed buf I think better)
                    if (now-item.lastused>TREECOPYPRUNETIME)
                        treeCopyArray.remove(i1);
                    else if (!tc.get()&&item.equals(srcfn,net,mask,sz,dt)) {
                        tc.set(&item);
                        item.lastused = now;
                    }
                }
                if (!tc.get()) {
                    if (treeCopyArray.ordinality()>=TREECOPY_CACHE_SIZE)
                        treeCopyArray.remove(0);
                    tc.setown(new CTreeCopyItem(srcfn,net,mask,sz,dt));
                    treeCopyArray.append(*tc.getLink());
                }
                ForEachItemInRev(cand,tc->loc) { // rev to choose copied locations first (maybe optional?)
                    if (!tc->busy->testSet(cand)) {
                        // check file accessible and matches
                        if (!cand&&dstfn.equals(tc->loc.item(cand)))  // hmm trying to overwrite existing, better humor
                            continue;
                        bool ok = true;
                        Owned<IFile> rmtfile = createIFile(tc->loc.item(cand));
                        if (cand) { // only need to check if remote
                            try {
                                if (rmtfile->size()!=sz)
                                    ok = false;
                                else {
                                    CDateTime fdt;
                                    rmtfile->getTime(NULL,&fdt,NULL);
                                    ok = fdt.equals(dt);
                                }
                            }
                            catch (IException *e) {
                                EXCLOG(e,"treeCopyFile(2)");
                                e->Release();
                                ok = false;
                            }
                        }
                        if (ok) { // if not ok leave 'busy'
                            // finally lets try and copy!
                            try {
                                if (TF_TRACE_TREE_COPY)
                                    PROGLOG("TREECOPY(started) %s to %s",rmtfile->queryFilename(),dstfile->queryFilename());
                                {
                                    CriticalUnblock unblock(treeCopyCrit); // note we have tc linked
                                    rmtfile->copyTo(dstfile,DEFAULT_COPY_BLKSIZE,NULL,usetmp,copyFlags);
                                }
                                if (TF_TRACE_TREE_COPY)
                                    PROGLOG("TREECOPY(done) %s to %s",rmtfile->queryFilename(),dstfile->queryFilename());
                                tc->busy->set(cand,false);
                                if (treeCopyWaiting)
                                    treeCopySem.signal((treeCopyWaiting>1)?2:1);
                                // add to known locations
                                tc->busy->set(tc->loc.ordinality(),false); // prob already is clear
                                tc->loc.append(dstfn);
                                ip.ipset(tc->loc.item(cand).queryIP());
                                return;
                            }
                            catch (IException *e) {
                                if (cand==0) {
                                    tc->busy->set(0,false); // don't leave busy
                                    if (treeCopyWaiting)
                                        treeCopySem.signal();
                                    throw;      // what more can we do!
                                }
                                EXCLOG(e,"treeCopyFile(3)");
                                e->Release();
                            }
                        }
                    }
                }
                // all locations busy
                if (msTick()-start>TREECOPYTIMEOUT) {
                    WARNLOG("Treecopy %s wait timed out", srcfile->queryFilename());
                    break;
                }
                treeCopyWaiting++; // note this isn't precise - just indication
                {
                    CriticalUnblock unblock(treeCopyCrit);
                    if (throttler)
                    {
                        CThrottleReleaseBlock block(*throttler, RFCtreecopy);
                        treeCopySem.wait(TREECOPYPOLLTIME);
                    }
                    else
                        treeCopySem.wait(TREECOPYPOLLTIME);
                }
                treeCopyWaiting--;
                if ((msTick()-start)/10*1000!=lastmin) {
                    lastmin = (msTick()-start)/10*1000;
                    PROGLOG("treeCopyFile delayed: %s to %s",srcfile->queryFilename(),dstfile->queryFilename());
                }
            }
        }
        else if (TF_TRACE_TREE_COPY)
            PROGLOG("TREECOPY source on same node as destination");
        if (TF_TRACE_TREE_COPY)
            PROGLOG("TREECOPY(started,fallback) %s to %s",srcfile->queryFilename(),dstfile->queryFilename());
        try {
            GetHostIp(ip);
            srcfile->copyTo(dstfile,DEFAULT_COPY_BLKSIZE,NULL,usetmp,copyFlags);
        }
        catch (IException *e) {
            EXCLOG(e,"TREECOPY(done,fallback)");
            throw;
        }
        if (TF_TRACE_TREE_COPY)
            PROGLOG("TREECOPY(done,fallback) %s to %s",srcfile->queryFilename(),dstfile->queryFilename());
    }

    void cmdTreeCopy(MemoryBuffer &msg, MemoryBuffer &reply, CRemoteClientHandler &client, CThrottler *throttler, bool usetmp=false)
    {
        IMPERSONATE_USER(client);
        RemoteFilename src;
        src.deserialize(msg);
        RemoteFilename dst;
        dst.deserialize(msg);
        StringAttr net;
        StringAttr mask;
        msg.read(net).read(mask);
        IpAddress ip;
        treeCopyFile(src,dst,net,mask,ip,usetmp,throttler);
        unsigned status = 0;
        reply.append((unsigned)RFEnoerror).append((unsigned)status);
        ip.ipserialize(reply);
    }

    void cmdTreeCopyTmp(MemoryBuffer &msg, MemoryBuffer &reply, CRemoteClientHandler &client, CThrottler *throttler)
    {
        cmdTreeCopy(msg, reply, client, throttler, true);
    }

    void cmdGetCRC(MemoryBuffer &msg, MemoryBuffer &reply, CRemoteClientHandler &client)
    {
        IMPERSONATE_USER(client);
        StringAttr name;
        msg.read(name);
        if (TF_TRACE)
            PROGLOG("getCRC,  '%s'",name.get());
        Owned<IFile> file=createIFile(name);
        unsigned ret = file->getCRC();
        reply.append((unsigned)RFEnoerror).append(ret);
    }

    void cmdStop(MemoryBuffer &msg, MemoryBuffer &reply)
    {
        PROGLOG("Abort request received");
        stopping = true;
        if (acceptsock)
            acceptsock->cancel_accept();
        if (securesock)
            securesock->cancel_accept();
        reply.append((unsigned)RFEnoerror);
    }

    void cmdExec(MemoryBuffer &msg, MemoryBuffer &reply, CRemoteClientHandler &client)
    {
        StringAttr cmdLine;
        msg.read(cmdLine);
        // NB: legacy remoteExec used to simply pass error code and buffer back to caller.
        VStringBuffer errMsg("Remote command execution no longer supported. Trying to execute cmdline=%s", cmdLine.get());
        WARNLOG("%s", errMsg.str());
        size32_t outSz = errMsg.length()+1; // reply with null terminated string
        // reply with error code -1
        reply.append((unsigned)-1).append((unsigned)0).append(outSz).append(outSz, errMsg.str());
    }

    void cmdSetTrace(MemoryBuffer &msg, MemoryBuffer &reply)
    {
        byte flags;
        msg.read(flags);
        int retcode=-1;
        if (flags!=255)   // escape
        {
            retcode = traceFlags;
            traceFlags = flags;
        }
        reply.append(retcode);
    }

    void cmdGetInfo(MemoryBuffer &msg, MemoryBuffer &reply)
    {
        unsigned level=1;
        if (msg.remaining() >= sizeof(unsigned))
            msg.read(level);
        StringBuffer retstr;
        getInfo(retstr, level);
        reply.append(RFEnoerror).append(retstr.str());
    }

    void cmdFirewall(MemoryBuffer &msg, MemoryBuffer &reply)
    {
        // TBD
        StringBuffer retstr;
        getInfo(retstr);
        reply.append(RFEnoerror).append(retstr.str());
    }

    void cmdExtractBlobElements(MemoryBuffer &msg, MemoryBuffer &reply, CRemoteClientHandler &client)
    {
        IMPERSONATE_USER(client);
        StringAttr prefix;
        StringAttr filename;
        msg.read(prefix).read(filename);
        RemoteFilename rfn;
        rfn.setLocalPath(filename);
        ExtractedBlobArray extracted;
        extractBlobElements(prefix, rfn, extracted);
        unsigned n = extracted.ordinality();
        reply.append((unsigned)RFEnoerror).append(n);
        for (unsigned i=0;i<n;i++)
            extracted.item(i).serialize(reply);
    }

    void cmdUnlock(MemoryBuffer & msg, MemoryBuffer & reply,CRemoteClientHandler &client)
    {
        // this is an attempt to authenticate when we haven't got authentication turned on
        if (TF_TRACE_CLIENT_STATS)
        {
            StringBuffer s(client.queryPeerName());
            PROGLOG("Connect from %s",s.str());
        }
        throw createDafsException(RFSERR_InvalidCommand, nullptr);
    }

    void cmdStreamReadCommon(MemoryBuffer & msg, MemoryBuffer & reply, CRemoteClientHandler &client)
    {
        size32_t jsonSz = msg.remaining();
        Owned<IPropertyTree> requestTree = createPTreeFromJSONString(jsonSz, (const char *)msg.readDirect(jsonSz));

        /* Example JSON request:
         * {
         *  "format" : "binary",
         *  "handle" : "1234",
         *  "replyLimit" : "64",
         *  "outputCompression" : "LZ4",
         *  "node" : {
         *   "kind" : "diskread",
         *   "fileName": "examplefilename",
         *   "keyFilter" : "f1='1    '",
         *   "chooseN" : 5,
         *   "compressed" : "false"
         *   "input" : {
         *    "f1" : "string5",
         *    "f2" : "string5"
         *   },
         *   "output" : {
         *    "f2" : "string",
         *    "f1" : "real"
         *   }
         *  }
         * }
         * {
         *  "format" : "xml",
         *  "handle" : "1234",
         *  "replyLimit" : "64",
         *  "node" : {
         *   "kind" : "diskread",
         *   "fileName": "examplefilename",
         *   "keyFilter" : "f1='1    '",
         *   "chooseN" : 5,
         *   "compressed" : "false"
         *   "input" : {
         *    "f1" : "string5",
         *    "f2" : "string5"
         *   },
         *   "output" : {
         *    "f2" : "string",
         *    "f1" : "real"
         *   }
         *  }
         * }
         * OR
         * {
         *  "format" : "xml",
         *  "handle" : "1234",
         *  "node" : {
         *   "kind" : "indexread",
         *   "fileName": "examplefilename",
         *   "keyFilter" : "f1='1    '",
         *   "rowLimit" : 5,
         *   "input" : {
         *    "f1" : "string5",
         *    "f2" : "string5"
         *   },
         *   "output" : {
         *    "f2" : "string",
         *    "f1" : "real"
         *   }
         *  }
         * }
         * OR
         * {
         *  "format" : "xml",
         *  "node" : {
         *   "action" : "count",            // if present performs count with/without filter and returns count
         *   "fileName": "examplefilename", // can be either index or flat file
         *   "keyFilter" : "f1='1    '",
         *   "rowLimit" : 5
         *   "input" : {
         *    "f1" : "string5",
         *    "f2" : "string5"
         *   },
         *  }
         * }
         *
         */

        int cursorHandle = requestTree->getPropInt("handle");
        OutputFormat outputFormat = outFmt_Xml;
        unsigned __int64 replyLimit = 0;
        Owned<ICompressor> compressor;
        MemoryBuffer compressMb;

        Owned<IRemoteActivity> outputActivity;
        OpenFileInfo fileInfo;
        if (!cursorHandle)
        {
            const char *outputFmtStr = requestTree->queryProp("format");
            if (nullptr == outputFmtStr)
                outputFormat = outFmt_Xml; // default
            else if (strieq("xml", outputFmtStr))
                outputFormat = outFmt_Xml;
            else if (strieq("json", outputFmtStr))
                outputFormat = outFmt_Json;
            else if (strieq("binary", outputFmtStr))
                outputFormat = outFmt_Binary;
            else
                throw MakeStringException(0, "Unrecognised output format: %s", outputFmtStr);

            replyLimit = requestTree->getPropInt64("replyLimit", defaultDaFSReplyLimitKB) * 1024;

            if (requestTree->hasProp("outputCompression"))
            {
                const char *outputCompressionType = requestTree->queryProp("outputCompression");
                if (isEmptyString(outputCompressionType))
                    compressor.setown(queryDefaultCompressHandler()->getCompressor());
                else if (outFmt_Binary == outputFormat)
                {
                    compressor.setown(getCompressor(outputCompressionType));
                    if (!compressor)
                        WARNLOG("Unknown compressor type specified: %s", outputCompressionType);
                }
                else
                    WARNLOG("Output compression not supported for format: %s", outputFmtStr);
            }


            // In future this may be passed the request and build a chain of activities and return sink.
            outputActivity.setown(createOutputActivity(*requestTree, authorizedOnly, keyPairInfo));

            Owned<CRemoteRequest> remoteRequest = new CRemoteRequest(outputFormat, compressor, replyLimit, outputActivity);

            StringBuffer requestStr("jsonrequest:");
            outputActivity->getInfoStr(requestStr);
            Owned<StringAttrItem> name = new StringAttrItem(requestStr);

            CriticalBlock block(sect);
            cursorHandle = getNextHandle();
            client.previdx = client.openFiles.ordinality();
            client.openFiles.append(OpenFileInfo(cursorHandle, remoteRequest, name));
        }
        else if (!lookupFileIOHandle(cursorHandle, fileInfo))
            cursorHandle = 0; // challenge response ..
        else // known handle, continuation
        {
            outputActivity.set(fileInfo.remoteRequest->queryActivity());
            compressor.set(fileInfo.remoteRequest->queryCompressor());
            outputFormat = fileInfo.remoteRequest->queryFormat();
            replyLimit = fileInfo.remoteRequest->queryReplyLimit();
        }

        if (outputActivity && requestTree->hasProp("cursorBin")) // use handle if one provided
        {
            MemoryBuffer cursorMb;
            cursorMb.setEndian(__BIG_ENDIAN);
            JBASE64_Decode(requestTree->queryProp("cursorBin"), cursorMb);
            outputActivity->restoreCursor(cursorMb);
        }

        Owned<IXmlWriterExt> responseWriter; // for xml or json response
        if (outFmt_Binary == outputFormat)
            reply.append(cursorHandle);
        else // outFmt_Xml || outFmt_Json
        {
            responseWriter.setown(createIXmlWriterExt(0, 0, nullptr, outFmt_Xml == outputFormat ? WTStandard : WTJSONObject));
            responseWriter->outputBeginNested("Response", true);
            if (outFmt_Xml == outputFormat)
                responseWriter->outputCString("urn:hpcc:dfs", "@xmlns:dfs");
            responseWriter->outputUInt(cursorHandle, sizeof(cursorHandle), "handle");
        }
        if (cursorHandle)
        {
            IOutputMetaData *out = outputActivity->queryOutputMeta();
            bool grouped = outputActivity->isGrouped();
            bool eoi=false;

            MemoryBuffer resultBuffer;
            MemoryBufferBuilder outBuilder(resultBuffer, out->getMinRecordSize());
            if (outFmt_Binary == outputFormat)
            {
                if (compressor)
                {
                    compressMb.setEndian(__BIG_ENDIAN);
                    compressMb.append(reply);
                }

                DelayedMarker<size32_t> dataLenMarker(compressor ? compressMb : reply); // data length

                if (compressor)
                {
                    size32_t initialSz = replyLimit >= 0x10000 ? 0x10000 : replyLimit;
                    compressor->open(compressMb, initialSz);
                }

                outBuilder.setBuffer(reply); // write direct to reply buffer for efficiency
                unsigned __int64 numProcessedStart = outputActivity->queryProcessed();
                size32_t totalDataSz = 0;
                size32_t dataStartPos = reply.length();

                if (grouped)
                {
                    bool pastFirstRow = numProcessedStart>0;
                    do
                    {
                        size32_t eogPos = 0;
                        if (pastFirstRow)
                        {
                            /* this is for last row output, which might have been returned in the previous request
                             * The eog marker may change as a result of the next row (see writeDirect() call below);
                             */
                            eogPos = reply.length();
                            reply.append(false);
                        }
                        size32_t rowSz;
                        const void *row = outputActivity->nextRow(outBuilder, rowSz);
                        if (!row)
                        {
                            if (!pastFirstRow)
                            {
                                eoi = true;
                                break;
                            }
                            else
                            {
                                bool eog = true;
                                reply.writeDirect(eogPos, sizeof(eog), &eog);
                                row = outputActivity->nextRow(outBuilder, rowSz);
                                if (!row)
                                {
                                    eoi = true;
                                    break;
                                }
                            }
                        }
                        pastFirstRow = true;
                    }
                    while (!handleFull(reply, dataStartPos, compressMb, compressor, replyLimit, totalDataSz));
                }
                else
                {
                    do
                    {
                        size32_t rowSz;
                        const void *row = outputActivity->nextRow(outBuilder, rowSz);
                        if (!row)
                        {
                            eoi = true;
                            break;
                        }
                    }
                    while (!handleFull(reply, dataStartPos, compressMb, compressor, replyLimit, totalDataSz));
                }

                // Consume any trailing data remaining
                if (compressor)
                {
                    size32_t sz = reply.length()-dataStartPos;
                    if (sz)
                    {
                        // consumes data built up in reply buffer into compressor
                        totalDataSz += sz;
                        const void *data = reply.bytes()+dataStartPos;
                        assertex(compressor->write(data, sz) == sz);
                        reply.setLength(dataStartPos);
                    }
                }

                // finalize reply
                dataLenMarker.write(compressor ? totalDataSz : reply.length()-dataStartPos);
                DelayedSizeMarker cursorLenMarker(reply); // cursor length
                if (!eoi)
                    outputActivity->serializeCursor(reply);
                cursorLenMarker.write();
                if (compressor)
                {
                    // consume cursor into compressor
                    size32_t sz = reply.length()-dataStartPos;
                    const void *data = reply.bytes()+dataStartPos;
                    assertex(compressor->write(data, sz) == sz);
                    compressor->close();
                    // now ready to swap compressed output into reply
                    reply.swapWith(compressMb);
                }
            }
            else
            {
                responseWriter->outputBeginArray("Row");
                if (grouped)
                {
                    bool pastFirstRow = outputActivity->queryProcessed()>0;
                    bool first = true;
                    do
                    {
                        size32_t rowSz;
                        const void *row = outputActivity->nextRow(outBuilder, rowSz);
                        if (!row)
                        {
                            if (!pastFirstRow)
                            {
                                eoi = true;
                                break;
                            }
                            else
                            {
                                row = outputActivity->nextRow(outBuilder, rowSz);
                                if (!row)
                                {
                                    eoi = true;
                                    break;
                                }
                                if (first) // possible if eog was 1st row on next packet
                                    responseWriter->outputBeginNested("Row", false);
                                responseWriter->outputBool(true, "dfs:Eog"); // field name cannot clash with an ecl field name
                            }
                        }
                        if (pastFirstRow)
                            responseWriter->outputEndNested("Row"); // close last row

                        responseWriter->outputBeginNested("Row", false);
                        out->toXML((const byte *)row, *responseWriter);
                        resultBuffer.clear();
                        pastFirstRow = true;
                        first = false;
                    }
                    while (responseWriter->length() < replyLimit);
                    if (pastFirstRow)
                        responseWriter->outputEndNested("Row"); // close last row
                }
                else
                {
                    do
                    {
                        size32_t rowSz;
                        const void *row = outputActivity->nextRow(outBuilder, rowSz);
                        if (!row)
                        {
                            eoi = true;
                            break;
                        }
                        responseWriter->outputBeginNested("Row", false);
                        out->toXML((const byte *)row, *responseWriter);
                        responseWriter->outputEndNested("Row");
                        resultBuffer.clear();
                    }
                    while (responseWriter->length() < replyLimit);
                }
                responseWriter->outputEndArray("Row");
                if (!eoi)
                {
                    MemoryBuffer cursorMb;
                    cursorMb.setEndian(__BIG_ENDIAN);
                    outputActivity->serializeCursor(cursorMb);
                    StringBuffer cursorBinStr;
                    JBASE64_Encode(cursorMb.toByteArray(), cursorMb.length(), cursorBinStr);
                    responseWriter->outputString(cursorBinStr.length(), cursorBinStr.str(), "cursorBin");
                }
            }
        }
        if (outFmt_Binary != outputFormat)
        {
            responseWriter->outputEndNested("Response");
            responseWriter->finalize();
            PROGLOG("Response: %s", responseWriter->str());
            reply.append(responseWriter->length(), responseWriter->str());
        }
    }

    void cmdStreamReadStd(MemoryBuffer & msg, MemoryBuffer & reply, CRemoteClientHandler &client)
    {
        reply.append(RFEnoerror);
        cmdStreamReadCommon(msg, reply, client);
    }

    void cmdStreamReadJSON(MemoryBuffer & msg, MemoryBuffer & reply, CRemoteClientHandler &client)
    {
        /* NB: exactly the same handling as cmdStreamReadStd(RFCStreamRead) for now,
         * may want to differentiate later
         * i.e. return format is { len[unsigned4-bigendian], errorcode[unsigned4-bigendian], result } - where result format depends on request output type.
         * errorcode = 0 means no error
         */
        reply.append(RFEnoerror);
        cmdStreamReadCommon(msg, reply, client);
    }

    void cmdStreamReadTestSocket(MemoryBuffer & msg, MemoryBuffer & reply, CRemoteClientHandler &client)
    {
        reply.append('J');
        cmdStreamReadCommon(msg, reply, client);
    }

    // legacy version
    void cmdSetThrottle(MemoryBuffer & msg, MemoryBuffer & reply)
    {
        unsigned limit, delayMs, cpuThreshold;
        msg.read(limit);
        msg.read(delayMs);
        msg.read(cpuThreshold);
        stdCmdThrottler.configure(limit, delayMs, cpuThreshold, (unsigned)-1);
        reply.append((unsigned)RFEnoerror);
    }

    void cmdSetThrottle2(MemoryBuffer & msg, MemoryBuffer & reply)
    {
        unsigned throttleClass, limit, delayMs, cpuThreshold, queueLimit;
        msg.read(throttleClass);
        msg.read(limit);
        msg.read(delayMs);
        msg.read(cpuThreshold);
        msg.read(queueLimit);
        setThrottle((ThrottleClass)throttleClass, limit, delayMs, cpuThreshold, queueLimit);
        reply.append((unsigned)RFEnoerror);
    }

    void formatException(MemoryBuffer &reply, IException *e, RemoteFileCommandType cmd, bool testSocketFlag, unsigned _dfsErrorCode, CRemoteClientHandler *client)
    {
        unsigned dfsErrorCode = _dfsErrorCode;
        if (!dfsErrorCode)
        {
            if (e)
                dfsErrorCode = (QUERYINTERFACE(e, IDAFS_Exception)) ? e->errorCode() : RFSERR_InternalError;
            else
                dfsErrorCode = RFSERR_InternalError;
        }
        VStringBuffer errMsg("ERROR: cmd=%s, error=%s", getRFCText(cmd), getRFSERRText(dfsErrorCode));
        if (e)
        {
            errMsg.appendf(" (%u, ", e->errorCode());
            unsigned len = errMsg.length();
            e->errorMessage(errMsg);
            if (len == errMsg.length())
                errMsg.setLength(len-2); // strip off ", " if no message in exception
            errMsg.append(")");
        }
        if (testSocketFlag)
            reply.append('-');
        else
            reply.append(dfsErrorCode);
        reply.append(errMsg.str());

        if (client && cmd!=RFCunlock)
        {
            const char *peer = client->queryPeerName();
            if (peer)
            {
                VStringBuffer err("%s. Client: %s", errMsg.str(), peer);
                PROGLOG("%s", err.str());
            }
            client->logPrevHandle();
        }
    }

    void throttleCommand(RemoteFileCommandType cmd, MemoryBuffer &msg, CRemoteClientHandler *client)
    {
        switch (cmd)
        {
            case RFCexec:
            case RFCgetcrc:
            case RFCcopy:
            case RFCappend:
            case RFCtreecopy:
            case RFCtreecopytmp:
                slowCmdThrottler.addCommand(cmd, msg, client);
                return;
            case RFCcloseIO:
            case RFCopenIO:
            case RFCread:
            case RFCsize:
            case RFCwrite:
            case RFCexists:
            case RFCremove:
            case RFCrename:
            case RFCgetver:
            case RFCisfile:
            case RFCisdirectory:
            case RFCisreadonly:
            case RFCsetreadonly:
            case RFCsetfileperms:
            case RFCreadfilteredindex:
            case RFCreadfilteredindexcount:
            case RFCreadfilteredindexblob:
            case RFCgettime:
            case RFCsettime:
            case RFCcreatedir:
            case RFCgetdir:
            case RFCmonitordir:
            case RFCstop:
            case RFCextractblobelements:
            case RFCredeploy:
            case RFCmove:
            case RFCsetsize:
            case RFCsettrace:
            case RFCgetinfo:
            case RFCfirewall:
            case RFCunlock:
            case RFCStreamRead:
            case RFCStreamReadTestSocket:
            case RFCStreamReadJSON:
                stdCmdThrottler.addCommand(cmd, msg, client);
                return;
            // NB: The following commands are still bound by the the thread pool
            case RFCsetthrottle: // legacy version
            case RFCsetthrottle2:
            case RFCcopysection: // slightly odd, but has it's own limit
            default:
            {
                client->processCommand(cmd, msg, NULL);
                break;
            }
        }
    }

    bool processCommand(RemoteFileCommandType cmd, MemoryBuffer & msg, MemoryBuffer & reply, CRemoteClientHandler *client, CThrottler *throttler)
    {
        Owned<CClientStats> stats = clientStatsTable.getClientReference(cmd, client->queryPeerName());
        bool testSocketFlag = false;
        unsigned posOfErr = reply.length();
        try
        {
            switch(cmd)
            {
                MAPCOMMANDSTATS(RFCread, cmdRead, *stats);
                MAPCOMMANDSTATS(RFCwrite, cmdWrite, *stats);
                MAPCOMMANDCLIENTSTATS(RFCappend, cmdAppend, *client, *stats);
                MAPCOMMAND(RFCcloseIO, cmdCloseFileIO);
                MAPCOMMANDCLIENT(RFCopenIO, cmdOpenFileIO, *client);
                MAPCOMMAND(RFCsize, cmdSize);
                MAPCOMMANDCLIENT(RFCexists, cmdExists, *client);
                MAPCOMMANDCLIENT(RFCremove, cmdRemove, *client);
                MAPCOMMANDCLIENT(RFCrename, cmdRename, *client);
                MAPCOMMAND(RFCgetver, cmdGetVer);
                MAPCOMMANDCLIENT(RFCisfile, cmdIsFile, *client);
                MAPCOMMANDCLIENT(RFCisdirectory, cmdIsDir, *client);
                MAPCOMMANDCLIENT(RFCisreadonly, cmdIsReadOnly, *client);
                MAPCOMMANDCLIENT(RFCsetreadonly, cmdSetReadOnly, *client);
                MAPCOMMANDCLIENT(RFCsetfileperms, cmdSetFilePerms, *client);
                MAPCOMMANDCLIENT(RFCgettime, cmdGetTime, *client);
                MAPCOMMANDCLIENT(RFCsettime, cmdSetTime, *client);
                MAPCOMMANDCLIENT(RFCcreatedir, cmdCreateDir, *client);
                MAPCOMMANDCLIENT(RFCgetdir, cmdGetDir, *client);
                MAPCOMMANDCLIENT(RFCmonitordir, cmdMonitorDir, *client);
                MAPCOMMAND(RFCstop, cmdStop);
                MAPCOMMANDCLIENT(RFCexec, cmdExec, *client);
                MAPCOMMANDCLIENT(RFCextractblobelements, cmdExtractBlobElements, *client);
                MAPCOMMANDCLIENT(RFCgetcrc, cmdGetCRC, *client);
                MAPCOMMANDCLIENT(RFCmove, cmdMove, *client);
                MAPCOMMANDCLIENT(RFCcopy, cmdCopy, *client);
                MAPCOMMAND(RFCsetsize, cmdSetSize);
                MAPCOMMAND(RFCsettrace, cmdSetTrace);
                MAPCOMMAND(RFCgetinfo, cmdGetInfo);
                MAPCOMMAND(RFCfirewall, cmdFirewall);
                MAPCOMMANDCLIENT(RFCunlock, cmdUnlock, *client);
                MAPCOMMANDCLIENT(RFCStreamRead, cmdStreamReadStd, *client);
                MAPCOMMANDCLIENT(RFCStreamReadJSON, cmdStreamReadJSON, *client);
                MAPCOMMANDCLIENTTESTSOCKET(RFCStreamReadTestSocket, cmdStreamReadTestSocket, *client);
                MAPCOMMANDCLIENT(RFCcopysection, cmdCopySection, *client);
                MAPCOMMANDCLIENTTHROTTLE(RFCtreecopy, cmdTreeCopy, *client, &slowCmdThrottler);
                MAPCOMMANDCLIENTTHROTTLE(RFCtreecopytmp, cmdTreeCopyTmp, *client, &slowCmdThrottler);
                MAPCOMMAND(RFCsetthrottle, cmdSetThrottle); // legacy version
                MAPCOMMAND(RFCsetthrottle2, cmdSetThrottle2);
            default:
                formatException(reply, nullptr, cmd, false, RFSERR_InvalidCommand, client);
                break;
            }
        }
        catch (IException *e)
        {
            reply.setWritePos(posOfErr);
            formatException(reply, e, cmd, testSocketFlag, 0, client);
        }
        return testSocketFlag;
    }

    IPooledThread *createCommandProcessor()
    {
        return new cCommandProcessor();
    }

    void run(DAFSConnectCfg _connectMethod, SocketEndpoint &listenep, unsigned sslPort)
    {
        SocketEndpoint sslep(listenep);
        if (sslPort)
            sslep.port = sslPort;
        else
            sslep.port = securitySettings.daFileSrvSSLPort;
        Owned<ISocket> acceptSocket, acceptSSLSocket;

        if (_connectMethod != SSLOnly)
        {
            if (listenep.port == 0)
                throw createDafsException(DAFSERR_serverinit_failed, "dafilesrv port not specified");

            if (listenep.isNull())
                acceptSocket.setown(ISocket::create(listenep.port));
            else
            {
                StringBuffer ips;
                listenep.getIpText(ips);
                acceptSocket.setown(ISocket::create_ip(listenep.port,ips.str()));
            }
        }

        if (_connectMethod == SSLOnly || _connectMethod == SSLFirst || _connectMethod == UnsecureFirst)
        {
            if (sslep.port == 0)
                throw createDafsException(DAFSERR_serverinit_failed, "Secure dafilesrv port not specified");

            if (_connectMethod == UnsecureFirst)
            {
                // don't fail, but warn - this allows for fast SSL client rejections
                if (!securitySettings.certificate)
                    WARNLOG("SSL Certificate information not found in environment.conf, cannot accept SSL connections");
                else if ( !checkFileExists(securitySettings.certificate) )
                {
                    WARNLOG("SSL Certificate File not found in environment.conf, cannot accept SSL connections");
                    securitySettings.certificate = nullptr;
                }
                if (!securitySettings.privateKey)
                    WARNLOG("SSL Key information not found in environment.conf, cannot accept SSL connections");
                else if ( !checkFileExists(securitySettings.privateKey) )
                {
                    WARNLOG("SSL Key File not found in environment.conf, cannot accept SSL connections");
                    securitySettings.privateKey = nullptr;
                }
            }
            else
            {
                if (!securitySettings.certificate)
                    throw createDafsException(DAFSERR_serverinit_failed, "SSL Certificate information not found in environment.conf");
                if (!checkFileExists(securitySettings.certificate))
                    throw createDafsException(DAFSERR_serverinit_failed, "SSL Certificate File not found in environment.conf");
                if (!securitySettings.privateKey)
                    throw createDafsException(DAFSERR_serverinit_failed, "SSL Key information not found in environment.conf");
                if (!checkFileExists(securitySettings.privateKey))
                    throw createDafsException(DAFSERR_serverinit_failed, "SSL Key File not found in environment.conf");
            }

            if (sslep.isNull())
                acceptSSLSocket.setown(ISocket::create(sslep.port));
            else
            {
                StringBuffer ips;
                sslep.getIpText(ips);
                acceptSSLSocket.setown(ISocket::create_ip(sslep.port,ips.str()));
            }
        }

        run(_connectMethod, acceptSocket.getClear(), acceptSSLSocket.getClear());
    }

    void run(DAFSConnectCfg _connectMethod, ISocket *regSocket, ISocket *secureSocket)
    {
        if (_connectMethod != SSLOnly)
        {
            if (regSocket)
                acceptsock.setown(regSocket);
            else
                throw createDafsException(DAFSERR_serverinit_failed, "Invalid non-secure socket");
        }

        if (_connectMethod == SSLOnly || _connectMethod == SSLFirst || _connectMethod == UnsecureFirst)
        {
            if (secureSocket)
                securesock.setown(secureSocket);
            else
                throw createDafsException(DAFSERR_serverinit_failed, "Invalid secure socket");
        }

        selecthandler->start();

        for (;;)
        {
            Owned<ISocket> sock;
            Owned<ISocket> sockSSL;
            bool sockavail = false;
            bool securesockavail = false;
            if (_connectMethod == SSLNone)
                sockavail = acceptsock->wait_read(1000*60*1)!=0;
            else if (_connectMethod == SSLOnly)
                securesockavail = securesock->wait_read(1000*60*1)!=0;
            else
            {
                UnsignedArray readSocks;
                UnsignedArray waitingSocks;
                readSocks.append(acceptsock->OShandle());
                readSocks.append(securesock->OShandle());
                int numReady = wait_read_multiple(readSocks, 1000*60*1, waitingSocks);
                if (numReady > 0)
                {
                    for (int idx = 0; idx < numReady; idx++)
                    {
                        if (waitingSocks.item(idx) == acceptsock->OShandle())
                            sockavail = true;
                        else if (waitingSocks.item(idx) == securesock->OShandle())
                            securesockavail = true;
                    }
                }
            }
#if 0
            if (!sockavail && !securesockavail)
            {
                JSocketStatistics stats;
                getSocketStatistics(stats);
                StringBuffer s;
                getSocketStatisticsString(stats,s);
                PROGLOG( "Socket statistics : \n%s\n",s.str());
            }
#endif

            if (stopping)
                break;

            if (sockavail || securesockavail)
            {
                if (sockavail)
                {
                    try
                    {
                        sock.setown(acceptsock->accept(true));
                        if (!sock||stopping)
                            break;
#ifdef _DEBUG
                        SocketEndpoint eps;
                        sock->getPeerEndpoint(eps);
                        StringBuffer sb;
                        eps.getUrlStr(sb);
                        PROGLOG("Server accepting from %s", sb.str());
#endif
                    }
                    catch (IException *e)
                    {
                        EXCLOG(e,"CRemoteFileServer");
                        e->Release();
                        break;
                    }
                }

                if (securesockavail)
                {
                    Owned<ISecureSocket> ssock;
                    try
                    {
                        sockSSL.setown(securesock->accept(true));
                        if (!sockSSL||stopping)
                            break;

                        if ( (_connectMethod == UnsecureFirst) && (!securitySettings.certificate || !securitySettings.privateKey) )
                        {
                            // for client secure_connect() to fail quickly ...
                            cleanupSocket(sockSSL);
                            sockSSL.clear();
                            securesockavail = false;
                        }
                        else
                        {
#ifdef _USE_OPENSSL
                            ssock.setown(createSecureSocket(sockSSL.getClear(), ServerSocket));
                            int status = ssock->secure_accept();
                            if (status < 0)
                                throw createDafsException(DAFSERR_serveraccept_failed,"Failure to establish secure connection");
                            sockSSL.setown(ssock.getLink());
#else
                            throw createDafsException(DAFSERR_serveraccept_failed,"Failure to establish secure connection: OpenSSL disabled in build");
#endif
#ifdef _DEBUG
                            SocketEndpoint eps;
                            sockSSL->getPeerEndpoint(eps);
                            StringBuffer sb;
                            eps.getUrlStr(sb);
                            PROGLOG("Server accepting SECURE from %s", sb.str());
#endif
                        }
                    }
                    catch (IJSOCK_Exception *e)
                    {
                        // accept failed ...
                        EXCLOG(e,"CRemoteFileServer (secure)");
                        e->Release();
                        break;
                    }
                    catch (IException *e) // IDAFS_Exception also ...
                    {
                        EXCLOG(e,"CRemoteFileServer1 (secure)");
                        e->Release();
                        cleanupSocket(sockSSL);
                        sockSSL.clear();
                        cleanupSocket(ssock);
                        ssock.clear();
                        securesockavail = false;
                    }
                }

                if (sockavail)
                    runClient(sock.getClear());

                if (securesockavail)
                    runClient(sockSSL.getClear());
            }
            else
                checkTimeout();
        }
        if (TF_TRACE_CLIENT_STATS)
            PROGLOG("CRemoteFileServer:run exiting");
        selecthandler->stop(true);
    }

    void processUnauthenticatedCommand(RemoteFileCommandType cmd, ISocket *socket, MemoryBuffer &msg)
    {
        // these are unauthenticated commands
        if (cmd != RFCgetver)
            cmd = RFCinvalid;
        MemoryBuffer reply;
        bool testSocketFlag = processCommand(cmd, msg, initSendBuffer(reply), NULL, NULL);
        sendBuffer(socket, reply, testSocketFlag);
    }

    bool checkAuthentication(ISocket *socket, IAuthenticatedUser *&ret)
    {
        ret = NULL;
        if (!AuthenticationEnabled)
            return true;
        MemoryBuffer reqbuf;
        MemoryBuffer reply;
        MemoryBuffer encbuf; // because aesEncrypt clears input
        initSendBuffer(reply);
        receiveBuffer(socket, reqbuf, 1);
        RemoteFileCommandType typ=0;
        if (reqbuf.remaining()<sizeof(RemoteFileCommandType))
            return false;
        reqbuf.read(typ);
        if (typ!=RFCunlock)
        {
            processUnauthenticatedCommand(typ,socket,reqbuf);
            return false;
        }
        if (reqbuf.remaining()<sizeof(OnceKey))
            return false;
        OnceKey oncekey;
        reqbuf.read(sizeof(oncekey),&oncekey);
        IpAddress ip;
        socket->getPeerAddress(ip);
        byte ipdata[16];
        ip.getNetAddress(sizeof(ipdata),&ipdata);
        mergeOnce(oncekey,sizeof(ipdata),&ipdata); // this is clients key
        OnceKey mykey;
        genOnce(mykey);
        reply.append(RFEnoerror); // errcode
        aesEncrypt(&oncekey,sizeof(oncekey),&mykey,sizeof(oncekey),encbuf);
        reply.append(encbuf.length()).append(encbuf);
        sendBuffer(socket, reply); // send my oncekey
        reqbuf.clear();
        receiveBuffer(socket, reqbuf, 1);
        if (reqbuf.remaining()>sizeof(RemoteFileCommandType)+sizeof(size32_t))
        {
            reqbuf.read(typ);
            if (typ==RFCunlockreply)
            {
                size32_t bs;
                reqbuf.read(bs);
                if (bs<=reqbuf.remaining())
                {
                    MemoryBuffer userbuf;
                    aesDecrypt(&mykey,sizeof(mykey),reqbuf.readDirect(bs),bs,userbuf);
                    byte n;
                    userbuf.read(n);
                    if (n>=2)
                    {
                        StringAttr user;
                        StringAttr password;
                        userbuf.read(user).read(password);
                        Owned<IAuthenticatedUser> iau = createAuthenticatedUser();
                        if (iau->login(user,password))
                        {
                            initSendBuffer(reply.clear());
                            reply.append(RFEnoerror);
                            sendBuffer(socket, reply); // send OK
                            ret = iau;
                            return true;
                        }
                    }
                }
            }
        }
        reply.clear();
        appendErr(reply, RFSERR_AuthenticateFailed);
        sendBuffer(socket, reply); // send OK
        return false;
    }

    void runClient(ISocket *sock)
    {
        cCommandProcessor::cCommandProcessorParams params;
        IAuthenticatedUser *user=NULL;
        bool authenticated = false;
        try
        {
            if (checkAuthentication(sock,user))
                authenticated = true;
        }
        catch (IException *e)
        {
            e->Release();
        }
        if (!authenticated)
        {
            try
            {
                sock->Release();
            }
            catch (IException *e)
            {
                e->Release();
            }
            return;
        }
        params.client = new CRemoteClientHandler(this,sock,user,globallasttick);
        {
            CriticalBlock block(sect);
            clients.append(*LINK(params.client));
        }
        // NB: This could be blocked, by thread pool limit
        threads->start(&params);
    }

    void stop()
    {
        // stop accept loop
        if (TF_TRACE_CLIENT_STATS)
            PROGLOG("CRemoteFileServer::stop");
        if (acceptsock)
            acceptsock->cancel_accept();
        if (securesock)
            securesock->cancel_accept();
        threads->stopAll();
        threads->joinAll(true,60*1000);
    }

    bool notify(CRemoteClientHandler *_client, MemoryBuffer &msg)
    {
        Linked<CRemoteClientHandler> client;
        client.set(_client);
        if (TF_TRACE_FULL)
            PROGLOG("notify %d", msg.length());
        if (msg.length())
        {
            if (TF_TRACE_FULL)
                PROGLOG("notify CRemoteClientHandler(%p), msg length=%u", _client, msg.length());
            cCommandProcessor::cCommandProcessorParams params;
            params.client = client.getClear();
            params.msg.swapWith(msg);

            /* This can block because the thread pool is full and therefore block the selecthandler
             * This is akin to the main server blocking post accept() for the same reason.
             */
            threads->start(&params);
        }
        else
            onCloseSocket(client,3);    // removes owned handles

        return false;
    }

    void addClient(CRemoteClientHandler *client)
    {
        if (client&&client->socket)
            selecthandler->add(client->socket,SELECTMODE_READ,client);
    }

    void checkTimeout()
    {
        if (msTick()-clientcounttick>1000*60*60)
        {
            CriticalBlock block(ClientCountSect);
            if (TF_TRACE_CLIENT_STATS && (ClientCount || MaxClientCount))
                PROGLOG("Client count = %d, max = %d", ClientCount, MaxClientCount);
            clientcounttick = msTick();
            MaxClientCount = ClientCount;
            if (closedclients)
            {
                if (TF_TRACE_CLIENT_STATS)
                    PROGLOG("Closed client count = %d",closedclients);
                closedclients = 0;
            }
        }
        CriticalBlock block(sect);
        ForEachItemInRev(i,clients)
        {
            CRemoteClientHandler &client = clients.item(i);
            if (client.timedOut())
            {
                StringBuffer s;
                bool ok = client.getInfo(s);    // will spot duff sockets
                if (ok&&(client.openFiles.ordinality()!=0))
                {
                    if (TF_TRACE_CLIENT_CONN && client.inactiveTimedOut())
                        WARNLOG("Inactive %s",s.str());
                }
                else
                {
#ifndef _DEBUG
                    if (TF_TRACE_CLIENT_CONN)
#endif
                        PROGLOG("Timing out %s",s.str());
                    closedclients++;
                    onCloseSocket(&client,4);   // removes owned handles
                }
            }
        }
    }

    void getInfo(StringBuffer &info, unsigned level=1)
    {
        {
            CriticalBlock block(ClientCountSect);
            info.append(VERSTRING).append('\n');
            info.appendf("Client count = %d\n",ClientCount);
            info.appendf("Max client count = %d",MaxClientCount);
        }
        CriticalBlock block(sect);
        ForEachItemIn(i,clients)
        {
            info.newline().append(i).append(": ");
            clients.item(i).getInfo(info);
        }
        info.newline().appendf("Running threads: %u", threadRunningCount());
        info.newline();
        stdCmdThrottler.getInfo(info);
        info.newline();
        slowCmdThrottler.getInfo(info);
        clientStatsTable.getInfo(info, level);
    }

    unsigned threadRunningCount()
    {
        if (!threads)
            return 0;
        return threads->runningCount();
    }

    unsigned idleTime()
    {
        unsigned t = (unsigned)atomic_read(&globallasttick);
        return msTick()-t;
    }

    void setThrottle(ThrottleClass throttleClass, unsigned limit, unsigned delayMs, unsigned cpuThreshold, unsigned queueLimit)
    {
        switch (throttleClass)
        {
            case ThrottleStd:
                stdCmdThrottler.configure(limit, delayMs, cpuThreshold, queueLimit);
                break;
            case ThrottleSlow:
                slowCmdThrottler.configure(limit, delayMs, cpuThreshold, queueLimit);
                break;
            default:
            {
                StringBuffer availableClasses("{ ");
                for (unsigned c=0; c<ThrottleClassMax; c++)
                {
                    availableClasses.append(c).append(" = ").append(getThrottleClassText((ThrottleClass)c));
                    if (c+1<ThrottleClassMax)
                        availableClasses.append(", ");
                }
                availableClasses.append(" }");
                throw MakeStringException(0, "Unknown throttle class: %u, available classes are: %s", (unsigned)throttleClass, availableClasses.str());
            }
        }
    }

    StringBuffer &getStats(StringBuffer &stats, bool reset)
    {
        CriticalBlock block(sect);
        stdCmdThrottler.getStats(stats, reset).newline();
        slowCmdThrottler.getStats(stats, reset);
        if (reset)
            clientStatsTable.reset();
        return stats;
    }
};


IRemoteFileServer * createRemoteFileServer(unsigned maxThreads, unsigned maxThreadsDelayMs, unsigned maxAsyncCopy, bool authorizedOnly, IPropertyTree *keyPairInfo)
{
#if SIMULATE_PACKETLOSS
    errorSimulationOn = false;
#endif

// NB: if no OOPENSSL, no authorization checks
#ifndef _USE_OPENSSL
    authorizedOnly = false;
#endif
    return new CRemoteFileServer(maxThreads, maxThreadsDelayMs, maxAsyncCopy, authorizedOnly, keyPairInfo);
}


#ifdef _USE_CPPUNIT
#include "unittests.hpp"

#include "rmtfile.hpp"

static unsigned serverPort = DAFILESRV_PORT+1; // do not use standard port, which if in a URL will be converted to local parth if IP is local
static StringBuffer basePath;
static Owned<CSimpleInterface> serverThread;


class RemoteFileSlowTest : public CppUnit::TestFixture
{
    CPPUNIT_TEST_SUITE(RemoteFileSlowTest);
        CPPUNIT_TEST(testRemoteFilename);
        CPPUNIT_TEST(testStartServer);
        CPPUNIT_TEST(testBasicFunctionality);
        CPPUNIT_TEST(testCopy);
        CPPUNIT_TEST(testOther);
        CPPUNIT_TEST(testConfiguration);
        CPPUNIT_TEST(testDirectoryMonitoring);
        CPPUNIT_TEST(testFinish);
    CPPUNIT_TEST_SUITE_END();

    size32_t testLen = 1024;

protected:
    void testRemoteFilename()
    {
        const char *rfns = "//1.2.3.4/dir1/file1|//1.2.3.4:7100/dir1/file1,"
                           "//1.2.3.4:7100/dir1/file1|//1.2.3.4:7100/dir1/file1,"
                           "//1.2.3.4/c$/dir1/file1|//1.2.3.4:7100/c$/dir1/file1,"
                           "//1.2.3.4:7100/c$/dir1/file1|//1.2.3.4:7100/c$/dir1/file1,"
                           "//1.2.3.4:7100/d$/dir1/file1|//1.2.3.4:7100/d$/dir1/file1";
        StringArray tests;
        tests.appendList(rfns, ",");

        ForEachItemIn(i, tests)
        {
            StringArray inOut;
            const char *pair = tests.item(i);
            inOut.appendList(pair, "|");
            const char *rfn = inOut.item(0);
            const char *expected = inOut.item(1);
            Owned<IFile> iFile = createIFile(rfn);
            const char *res = iFile->queryFilename();
            if (!streq(expected, res))
            {
                StringBuffer errMsg("testRemoteFilename MISMATCH");
                errMsg.newline().append("Expected: ").append(expected);
                errMsg.newline().append("Got: ").append(res);
                PROGLOG("%s", errMsg.str());
                CPPUNIT_ASSERT_MESSAGE(errMsg.str(), 0);
            }
            else
                PROGLOG("MATCH: %s", res);
        }
    }
    void testStartServer()
    {
        Owned<ISocket> socket;

        unsigned endPort = MP_END_PORT;
        while (1)
        {
            try
            {
                socket.setown(ISocket::create(serverPort));
                break;
            }
            catch (IJSOCK_Exception *e)
            {
                if (e->errorCode() != JSOCKERR_port_in_use)
                {
                    StringBuffer eStr;
                    e->errorMessage(eStr);
                    e->Release();
                    CPPUNIT_ASSERT_MESSAGE(eStr.str(), 0);
                }
                else if (serverPort == endPort)
                {
                    e->Release();
                    CPPUNIT_ASSERT_MESSAGE("Could not find a free port to use for remote file server", 0);
                }
            }
            ++serverPort;
        }

        basePath.append("//");
        SocketEndpoint ep(serverPort);
        ep.getUrlStr(basePath);

        char cpath[_MAX_DIR];
        if (!GetCurrentDirectory(_MAX_DIR, cpath))
            CPPUNIT_ASSERT_MESSAGE("Current directory path too big", 0);
        else
            basePath.append(cpath);
        addPathSepChar(basePath);

        PROGLOG("basePath = %s", basePath.str());

        class CServerThread : public CSimpleInterface, implements IThreaded
        {
            CThreaded threaded;
            Owned<CRemoteFileServer> server;
            Linked<ISocket> socket;
        public:
            CServerThread(CRemoteFileServer *_server, ISocket *_socket) : server(_server), socket(_socket), threaded("CServerThread")
            {
                threaded.init(this);
            }
            ~CServerThread()
            {
                threaded.join();
            }
        // IThreaded
            virtual void threadmain() override
            {
                DAFSConnectCfg sslCfg = SSLNone;
                server->run(sslCfg, socket, nullptr);
            }
        };
        enableDafsAuthentication(false);
        Owned<IRemoteFileServer> server = createRemoteFileServer();
        serverThread.setown(new CServerThread(QUERYINTERFACE(server.getClear(), CRemoteFileServer), socket.getClear()));
    }
    void testBasicFunctionality()
    {
        VStringBuffer filePath("%s%s", basePath.str(), "file1");

        // create file
        Owned<IFile> iFile = createIFile(filePath);
        CPPUNIT_ASSERT(iFile);
        Owned<IFileIO> iFileIO = iFile->open(IFOcreate);
        CPPUNIT_ASSERT(iFileIO);

        // write out 1k of random data and crc
        MemoryBuffer mb;
        char *buf = (char *)mb.reserveTruncate(testLen);
        for (unsigned b=0; b<1024; b++)
            buf[b] = getRandom()%256;
        CRC32 crc;
        crc.tally(testLen, buf);
        unsigned writeCrc = crc.get();

        size32_t sz = iFileIO->write(0, testLen, buf);
        CPPUNIT_ASSERT(sz == testLen);

        // close file
        iFileIO.clear();

        // validate remote crc
        CPPUNIT_ASSERT(writeCrc == iFile->getCRC());

        // exists
        CPPUNIT_ASSERT(iFile->exists());

        // validate size
        CPPUNIT_ASSERT(iFile->size() == testLen);

        // read back and validate read data's crc against written
        iFileIO.setown(iFile->open(IFOread));
        CPPUNIT_ASSERT(iFileIO);
        sz = iFileIO->read(0, testLen, buf);
        iFileIO.clear();
        CPPUNIT_ASSERT(sz == testLen);
        crc.reset();
        crc.tally(testLen, buf);
        CPPUNIT_ASSERT(writeCrc == crc.get());
    }
    void testCopy()
    {
        VStringBuffer filePath("%s%s", basePath.str(), "file1");
        Owned<IFile> iFile = createIFile(filePath);

        // test file copy
        VStringBuffer filePathCopy("%s%s", basePath.str(), "file1copy");
        Owned<IFile> iFile1Copy = createIFile(filePathCopy);
        iFile->copyTo(iFile1Copy);

        // read back copy and validate read data's crc against written
        Owned<IFileIO> iFileIO = iFile1Copy->open(IFOreadwrite); // open read/write for appendFile in next step.
        CPPUNIT_ASSERT(iFileIO);
        MemoryBuffer mb;
        char *buf = (char *)mb.reserveTruncate(testLen);
        size32_t sz = iFileIO->read(0, testLen, buf);
        CPPUNIT_ASSERT(sz == testLen);
        CRC32 crc;
        crc.tally(testLen, buf);
        CPPUNIT_ASSERT(iFile->getCRC() == crc.get());

        // check appendFile functionality. NB after this "file1copy" should be 2*testLen
        CPPUNIT_ASSERT(testLen == iFileIO->appendFile(iFile));
        iFileIO.clear();

        // validate new size
        CPPUNIT_ASSERT(iFile1Copy->size() == 2 * testLen);

        // setSize test, truncate copy to original size
        iFileIO.setown(iFile1Copy->open(IFOreadwrite));
        iFileIO->setSize(testLen);

        // validate new size
        CPPUNIT_ASSERT(iFile1Copy->size() == testLen);
    }
    void testOther()
    {
        VStringBuffer filePath("%s%s", basePath.str(), "file1");
        Owned<IFile> iFile = createIFile(filePath);
        // rename
        iFile->rename("file2");

        // create a directory
        VStringBuffer subDirPath("%s%s", basePath.str(), "subdir1");
        Owned<IFile> subDirIFile = createIFile(subDirPath);
        subDirIFile->createDirectory();

        // check isDirectory result
        CPPUNIT_ASSERT(subDirIFile->isDirectory());

        // move previous created and renamed file into new sub-directory
        // ensure not present before move
        VStringBuffer subDirFilePath("%s/%s", subDirPath.str(), "file2");
        Owned<IFile> iFile2 = createIFile(subDirFilePath);
        iFile2->remove();
        iFile->move(subDirFilePath);

        // open sub-directory file2 explicitly
        RemoteFilename rfn;
        rfn.setRemotePath(subDirPath.str());
        Owned<IFile> dir = createIFile(rfn);
        Owned<IDirectoryIterator> diriter = dir->directoryFiles("file2");
        if (!diriter->first())
        {
            CPPUNIT_ASSERT_MESSAGE("Error, file2 diriter->first() is null", 0);
        }

        Linked<IFile> iFile3 = &diriter->query();
        diriter.clear();
        dir.clear();

        OwnedIFileIO iFile3IO = iFile3->openShared(IFOread, IFSHfull);
        if (!iFile3IO)
        {
            CPPUNIT_ASSERT_MESSAGE("Error, file2 openShared() failed", 0);
        }
        iFile3IO->close();

        // count sub-directory files with a wildcard
        unsigned count=0;
        Owned<IDirectoryIterator> iter = subDirIFile->directoryFiles("*2");
        ForEach(*iter)
            ++count;
        CPPUNIT_ASSERT(1 == count);

        // check isFile result
        CPPUNIT_ASSERT(iFile2->isFile());

        // validate isReadOnly before after setting
        CPPUNIT_ASSERT(!iFile2->isReadOnly());
        iFile2->setReadOnly(true);
        CPPUNIT_ASSERT(iFile2->isReadOnly());

        // get/set Time and validate result
        CDateTime createTime, modifiedTime, accessedTime;
        CPPUNIT_ASSERT(subDirIFile->getTime(&createTime, &modifiedTime, &accessedTime));
        CDateTime newModifiedTime = modifiedTime;
        newModifiedTime.adjustTime(-86400); // -1 day
        CPPUNIT_ASSERT(subDirIFile->setTime(&createTime, &newModifiedTime, &accessedTime));
        CPPUNIT_ASSERT(subDirIFile->getTime(&createTime, &modifiedTime, &accessedTime));
        CPPUNIT_ASSERT(modifiedTime == newModifiedTime);

        // test set file permissions
        try
        {
            iFile2->setFilePermissions(0777);
        }
        catch (...)
        {
            CPPUNIT_ASSERT_MESSAGE("iFile2->setFilePermissions() exception", 0);
        }
    }
    void testConfiguration()
    {
        SocketEndpoint ep(serverPort); // test trace open connections
        CPPUNIT_ASSERT(setDafileSvrTraceFlags(ep, 0x08));

        StringBuffer infoStr;
        CPPUNIT_ASSERT(RFEnoerror == getDafileSvrInfo(ep, 10, infoStr));

        CPPUNIT_ASSERT(RFEnoerror == setDafileSvrThrottleLimit(ep, ThrottleStd, DEFAULT_STDCMD_PARALLELREQUESTLIMIT+1, DEFAULT_STDCMD_THROTTLEDELAYMS+1, DEFAULT_STDCMD_THROTTLECPULIMIT+1, DEFAULT_STDCMD_THROTTLEQUEUELIMIT+1));
    }
    void testDirectoryMonitoring()
    {
        VStringBuffer subDirPath("%s%s", basePath.str(), "subdir1");
        Owned<IFile> subDirIFile = createIFile(subDirPath);
        subDirIFile->createDirectory();

        VStringBuffer filePath("%s/%s", subDirPath.str(), "file1");
        class CDelayedFileCreate : implements IThreaded
        {
            CThreaded threaded;
            StringAttr filePath;
            Semaphore doneSem;
        public:
            CDelayedFileCreate(const char *_filePath) : filePath(_filePath), threaded("CDelayedFileCreate")
            {
                threaded.init(this);
            }
            ~CDelayedFileCreate()
            {
                stop();
            }
            void stop()
            {
                doneSem.signal();
                threaded.join();
            }
            // IThreaded impl.
            virtual void threadmain() override
            {
                MilliSleep(1000); // give monitorDirectory a chance to be monitoring

                // create file
                Owned<IFile> iFile = createIFile(filePath);
                CPPUNIT_ASSERT(iFile);
                Owned<IFileIO> iFileIO = iFile->open(IFOcreate);
                CPPUNIT_ASSERT(iFileIO);
                iFileIO.clear();

                doneSem.wait(60 * 1000);

                CPPUNIT_ASSERT(iFile->remove());
            }
        } delayedFileCreate(filePath);
        Owned<IDirectoryDifferenceIterator> iter = subDirIFile->monitorDirectory(nullptr, nullptr, false, false, 2000, 60 * 1000);
        ForEach(*iter)
        {
            StringBuffer fname;
            iter->getName(fname);
            PROGLOG("fname = %s", fname.str());
        }
        delayedFileCreate.stop();
    }
    void testFinish()
    {
        // clearup
        VStringBuffer filePathCopy("%s%s", basePath.str(), "file1copy");
        Owned<IFile> iFile1Copy = createIFile(filePathCopy);
        CPPUNIT_ASSERT(iFile1Copy->remove());

        VStringBuffer subDirPath("%s%s", basePath.str(), "subdir1");
        VStringBuffer subDirFilePath("%s/%s", subDirPath.str(), "file2");
        Owned<IFile> iFile2 = createIFile(subDirFilePath);
        CPPUNIT_ASSERT(iFile2->remove());

        Owned<IFile> subDirIFile = createIFile(subDirPath);
        CPPUNIT_ASSERT(subDirIFile->remove());

        SocketEndpoint ep(serverPort);
        Owned<ISocket> sock = ISocket::connect_timeout(ep, 60 * 1000);
        CPPUNIT_ASSERT(RFEnoerror == stopRemoteServer(sock));

        serverThread.clear();
    }
};

CPPUNIT_TEST_SUITE_REGISTRATION( RemoteFileSlowTest );
CPPUNIT_TEST_SUITE_NAMED_REGISTRATION( RemoteFileSlowTest, "RemoteFileSlowTests" );


#endif // _USE_CPPUNIT