// Created on: 1995-02-23
// Created by: Remi LEQUETTE
// Copyright (c) 1995-1999 Matra Datavision
// Copyright (c) 1999-2014 OPEN CASCADE SAS
//
// This file is part of Open CASCADE Technology software library.
//
// This library is free software; you can redistribute it and/or modify it under
// the terms of the GNU Lesser General Public License version 2.1 as published
// by the Free Software Foundation, with special exception defined in the file
// OCCT_LGPL_EXCEPTION.txt. Consult the file LICENSE_LGPL_21.txt included in OCCT
// distribution for complete text of the license and disclaimer of any warranty.
//
// Alternatively, this file may be used under the terms of Open CASCADE
// commercial license or contractual agreement.


#include <Draw.hxx>
#include <Draw_Appli.hxx>
#include <Draw_Chronometer.hxx>
#include <Draw_Drawable3D.hxx>
#include <Draw_Printer.hxx>
#include <Draw_ProgressIndicator.hxx>
#include <Message.hxx>
#include <Message_Messenger.hxx>
#include <OSD.hxx>
#include <OSD_Chronometer.hxx>
#include <OSD_Environment.hxx>
#include <OSD_Exception_CTRL_BREAK.hxx>
#include <OSD_MAllocHook.hxx>
#include <OSD_MemInfo.hxx>
#include <Standard_Macro.hxx>
#include <Standard_SStream.hxx>
#include <Standard_Stream.hxx>
#include <Standard_Version.hxx>
#include <TCollection_AsciiString.hxx>

#include <OSD_PerfMeter.h>
#ifdef _WIN32

#include <windows.h>
#include <winbase.h>
#include <process.h>
#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#include <limits>

#define RLIM_INFINITY   0x7fffffff

static clock_t CPU_CURRENT; // cpu time already used at last
                            // cpulimit call. (sec.) 
#else /* _WIN32 */

#include <sys/resource.h>
#include <signal.h>
#include <unistd.h>

#if defined (__hpux) || defined ( HPUX )
#define RLIM_INFINITY   0x7fffffff
#define	RLIMIT_CPU	0
#endif

#endif /* _WIN32 */

extern Standard_Boolean Draw_Batch;

static clock_t CPU_LIMIT;   // Cpu_limit in Sec.
static OSD_Timer aTimer;

//=======================================================================
// chronom
//=======================================================================

extern Standard_Boolean Draw_Chrono;

static Standard_Integer chronom(Draw_Interpretor& di,
				Standard_Integer n,const char** a)
{
  if ((n == 1) || (*a[1] == '0') || (*a[1] == '1')) {
    if (n == 1)
      Draw_Chrono = !Draw_Chrono;
    else
      Draw_Chrono = (*a[1] == '1');

    if (Draw_Chrono) di << "Chronometers activated.\n";
    else di << "Chronometers desactivated.\n";
  }
  else {
    Handle(Draw_Drawable3D) D = Draw::Get(a[1]);
    Handle(Draw_Chronometer) C;
    if (!D.IsNull()) {
      C = Handle(Draw_Chronometer)::DownCast(D);
    }
    if (C.IsNull()) {
      C = new Draw_Chronometer();
    Draw::Set(a[1],C,Standard_False);
    }
    if (n <= 2) {
      C->Timer().Reset();
    }
    else {
      if (!strcasecmp(a[2],"reset"))
	C->Timer().Reset();
      if (!strcasecmp(a[2],"start"))
	C->Timer().Start();
      if (!strcasecmp(a[2],"stop"))
	C->Timer().Stop();
      if (!strcasecmp(a[2],"show"))
	C->Timer().Show();
    }
  }
  return 0;
}

static Standard_Integer dchronom(Draw_Interpretor& I,
				 Standard_Integer n,const char** a)
{
  if ((n == 1) || (*a[1] == '0') || (*a[1] == '1')) {
    if (n == 1)
      Draw_Chrono = !Draw_Chrono;
    else
      Draw_Chrono = (*a[1] == '1');

    if (Draw_Chrono) I << "Chronometers activated.\n";
    else I << "Chronometers desactivated.\n";
  }
  else {
    Handle(Draw_Drawable3D) D = Draw::Get(a[1]);
    Handle(Draw_Chronometer) C;
    if (!D.IsNull()) {
      C = Handle(Draw_Chronometer)::DownCast(D);
    }
    if (C.IsNull()) {
      C = new Draw_Chronometer();
    Draw::Set(a[1],C,Standard_False);
    }
    if (n <= 2) {
      C->Timer().Reset();
    }
    else {
      if (!strcasecmp(a[2],"reset"))
	C->Timer().Reset();
      if (!strcasecmp(a[2],"start"))
	C->Timer().Start();
      if (!strcasecmp(a[2],"stop"))
	C->Timer().Stop();
      if (!strcasecmp(a[2],"show")) {
	Standard_SStream ss;
	C->Timer().Show(ss);
	I << ss;
      }
    }
  }
  return 0;
}



//=======================================================================
//function : ifbatch
//purpose  : 
//=======================================================================

static Standard_Integer ifbatch(Draw_Interpretor& DI, Standard_Integer , const char** )
{
  if (Draw_Batch)
    DI << "1";
  else
    DI << "0";
  
  return 0;
}

//=======================================================================
//function : spy
//purpose  : 
//=======================================================================

extern Standard_Boolean Draw_Spying;
extern filebuf Draw_Spyfile;

static Standard_Integer spy(Draw_Interpretor& di, Standard_Integer n, const char** a)
{
  if (Draw_Spying) 
    Draw_Spyfile.close();
  Draw_Spying = Standard_False;
  if (n > 1) {
    if (!Draw_Spyfile.open(a[1],ios::out)) {
      di << "Cannot open "<<a[1]<<" for writing\n";
      return 1;
    }
    Draw_Spying = Standard_True;
  }
  return 0;
}

static Standard_Integer dlog(Draw_Interpretor& di, Standard_Integer n, const char** a)
{
  if (n != 2 && n != 3)
  {
    cout << "Enable or disable logging: " << a[0] << " {on|off}" << endl;
    cout << "Reset log: " << a[0] << " reset" << endl;
    cout << "Get log content: " << a[0] << " get" << endl;
    return 1;
  }

  if (! strcmp (a[1], "on") && n == 2)
  {
    di.SetDoLog (Standard_True);
//    di.Log() << "dlog on" << endl; // for symmetry
  }
  else if (! strcmp (a[1], "off") && n == 2)
  {
    di.SetDoLog (Standard_False);
  }
  else if (! strcmp (a[1], "reset") && n == 2)
  {
    di.Log().str("");
  }
  else if (! strcmp (a[1], "get") && n == 2)
  {
    di << di.Log().str().c_str();
  }
  else if (! strcmp (a[1], "add") && n == 3)
  {
    di.Log() << a[2] << "\n";
  }
  else {
    cout << "Unrecognized option(s): " << a[1] << endl;
    return 1;
  }
  return 0;
}

static Standard_Integer decho(Draw_Interpretor& di, Standard_Integer n, const char** a)
{
  if (n != 2)
  {
    cout << "Enable or disable echoing: " << a[0] << " {on|off}" << endl;
    return 1;
  }

  if (! strcmp (a[1], "on"))
  {
    di.SetDoEcho (Standard_True);
  }
  else if (! strcmp (a[1], "off"))
  {
    di.SetDoEcho (Standard_False);
  }
  else {
    cout << "Unrecognized option: " << a[1] << endl;
    return 1;
  }
  return 0;
}

static Standard_Integer dbreak(Draw_Interpretor& di, Standard_Integer, const char**)
{
  try {
    OSD::ControlBreak();
  }
  catch (OSD_Exception_CTRL_BREAK) {
    di << "User pressed Control-Break";
    return 1; // Tcl exception
  }

  return 0;
}

static Standard_Integer dversion(Draw_Interpretor& di, Standard_Integer, const char**)
{
  // print OCCT version and OCCTY-specific macros used
  di << "Open CASCADE Technology " << OCC_VERSION_STRING_EXT << "\n";
#ifdef OCCT_DEBUG
  di << "Extended debug mode\n";
#elif defined(_DEBUG)
  di << "Debug mode\n";
#endif
#ifdef HAVE_TBB
  di << "TBB enabled (HAVE_TBB)\n";
#else 
  di << "TBB disabled\n";
#endif
#ifdef HAVE_GL2PS
  di << "GL2PS enabled (HAVE_GL2PS)\n";
#else
  di << "GL2PS disabled\n";
#endif
#ifdef HAVE_FREEIMAGE
  di << "FreeImage enabled (HAVE_FREEIMAGE)\n";
#else
  di << "FreeImage disabled\n";
#endif
#ifdef HAVE_GLES2
  di << "OpenGL: ES2\n";
#else
  di << "OpenGL: desktop\n";
#endif
#ifdef HAVE_VTK
  di << "VTK enabled (HAVE_VTK)\n";
#else
  di << "VTK disabled\n";
#endif
#ifdef No_Exception
  di << "Exceptions disabled (No_Exception)\n";
#else
  di << "Exceptions enabled\n";
#endif

  // check compiler, OS, etc. using pre-processor macros provided by compiler
  // see "Pre-defined C/C++ Compiler Macros" http://sourceforge.net/p/predef/wiki/
  // note that only modern compilers that are known to be used for OCCT are recognized

  // compiler; note that GCC and MSVC are last as other compilers (e.g. Intel) can also define __GNUC__ and _MSC_VER
#if defined(__INTEL_COMPILER)
  di << "Compiler: Intel " << __INTEL_COMPILER << "\n";
#elif defined(__BORLANDC__)
  di << "Compiler: Borland C++ (__BORLANDC__ = " << __BORLANDC__ << ")\n";
#elif defined(__clang__)
  di << "Compiler: Clang " << __clang_major__ << "." << __clang_minor__ << "." << __clang_patchlevel__ << "\n";
#elif defined(__SUNPRO_C)
  di << "Compiler: Sun Studio (__SUNPRO_C = " << __SUNPROC_C << ")\n";
#elif defined(_MSC_VER)
  #if _MSC_VER < 1900
    di << "Compiler: MS Visual C++ " << (int)(_MSC_VER/100-6) << "." << (int)((_MSC_VER/10)-60-10*(int)(_MSC_VER/100-6)) << " (_MSC_FULL_VER = " << _MSC_FULL_VER << ")\n";
  #else
    di << "Compiler: MS Visual C++ " << (int)(_MSC_VER/100-5) << "." << (int)((_MSC_VER/10)-50-10*(int)(_MSC_VER/100-5)) << " (_MSC_FULL_VER = " << _MSC_FULL_VER << ")\n";
  #endif
#elif defined(__GNUC__)
  di << "Compiler: GCC " << __GNUC__ << "." << __GNUC_MINOR__ << "." << __GNUC_PATCHLEVEL__ << "\n";
#else
  di << "Compiler: unrecognized\n";
#endif

  // Cygwin and MinGW specifics
#if defined(__CYGWIN__)
  di << "Cygwin\n";
#endif
#if defined(__MINGW64__)
  di << "MinGW 64 " << __MINGW64_VERSION_MAJOR << "." << __MINGW64_VERSION_MINOR << "\n";
#elif defined(__MINGW32__)
  di << "MinGW 32 " << __MINGW32_MAJOR_VERSION << "." << __MINGW32_MINOR_VERSION << "\n";
#endif 

  // architecture
#if defined(__amd64) || defined(__x86_64) || defined(_M_AMD64)
  di << "Architecture: AMD64\n";
#elif defined(__i386) || defined(_M_IX86) || defined(__X86__)|| defined(_X86_)
  di << "Architecture: Intel x86\n";
#elif defined(_M_IA64) || defined(__ia64__)
  di << "Architecture: Intel Itanium (IA 64)\n";
#elif defined(__sparc__) || defined(__sparc)
  di << "Architecture: SPARC\n";
#else
  di << "Architecture: unrecognized\n";
#endif

  // OS
#if defined(_WIN32) || defined(__WINDOWS__) || defined(__WIN32__)
  di << "OS: Windows\n";
#elif defined(__APPLE__) || defined(__MACH__)
  di << "OS: Mac OS X\n";
#elif defined(__sun) 
  di << "OS: SUN Solaris\n";
#elif defined(__ANDROID__) /* must be before Linux */
  #include <android/api-level.h>
  di << "OS: Android (__ANDROID_API__ = " << __ANDROID_API__ << ")\n";
#elif defined(__QNXNTO__)
  di << "OS: QNX Neutrino\n";
#elif defined(__QNX__)
  di << "OS: QNX\n";
#elif defined(__linux__)
  di << "OS: Linux\n";
#elif defined(__FreeBSD__) || defined(__OpenBSD__) || defined(__NetBSD__) || defined(__DragonFly__)
  #include <sys/param.h>
  di << "OS: BSD (BSD = " << BSD << ")\n";
#else
  di << "OS: unrecognized\n";
#endif

  return 0;
}

//=======================================================================
//function : wait
//purpose  : 
//=======================================================================

static Standard_Integer Draw_wait(Draw_Interpretor& , Standard_Integer n, const char** a)
{
  Standard_Integer w = 10;
  if (n > 1)
    w = Draw::Atoi(a[1]);
  time_t ct = time(NULL) + w;
  while (time(NULL) < ct) {};
  return 0;
}

//=======================================================================
//function : cpulimit
//purpose  : 
//=======================================================================
#ifdef _WIN32
static unsigned int __stdcall CpuFunc (void * /*param*/)
{
  clock_t anElapCurrent;
  clock_t aCurrent;

  for(;;)
  {
    Sleep (5);
    Standard_Real anUserSeconds, aSystemSeconds;
    OSD_Chronometer::GetProcessCPU (anUserSeconds, aSystemSeconds);
    aCurrent = clock_t(anUserSeconds + aSystemSeconds);
    anElapCurrent = clock_t(aTimer.ElapsedTime());
    
    if (CPU_LIMIT > 0 && (aCurrent - CPU_CURRENT) >= CPU_LIMIT)
    {
      cout << "Process killed by CPU limit (" << CPU_LIMIT << " sec)" << endl;
      aTimer.Stop();
      ExitProcess (2);
    }
    if (CPU_LIMIT > 0 && anElapCurrent >= CPU_LIMIT)
    {
      cout << "Process killed by elapsed limit (" << CPU_LIMIT << " sec)" << endl;
      aTimer.Stop();
      ExitProcess (2);
    }
  }
}
#else
static void cpulimitSignalHandler (int)
{
  cout << "Process killed by CPU limit  (" << CPU_LIMIT << " sec)" << endl;
  exit(2);
}
static void *CpuFunc(void* /*threadarg*/)
{
  clock_t anElapCurrent;
  for(;;)
  {
    sleep (5);
    anElapCurrent = clock_t(aTimer.ElapsedTime());
    if (CPU_LIMIT >0 && (anElapCurrent) >= CPU_LIMIT) {
      cout << "Process killed by elapsed limit  (" << CPU_LIMIT << " sec)" << endl;
      exit(2);
    }
  }
  return NULL;
}
#endif

#ifdef _WIN32
static Standard_Integer cpulimit(Draw_Interpretor&, Standard_Integer n, const char** a)
{
#else
static Standard_Integer cpulimit(Draw_Interpretor& di, Standard_Integer n, const char** a)
{
#endif
  static int aFirst = 1;
#ifdef _WIN32
  // Windows specific code
  unsigned int __stdcall CpuFunc (void *);
  unsigned aThreadID;

  if (n <= 1){
    CPU_LIMIT = RLIM_INFINITY;
  } else {
    CPU_LIMIT = Draw::Atoi (a[1]);
    Standard_Real anUserSeconds, aSystemSeconds;
    OSD_Chronometer::GetProcessCPU (anUserSeconds, aSystemSeconds);
    CPU_CURRENT = clock_t(anUserSeconds + aSystemSeconds);
    aTimer.Reset();
    aTimer.Start();
    if (aFirst) // Launch the thread only at the 1st call.
    {
      aFirst = 0;
      _beginthreadex (NULL, 0, CpuFunc, NULL, 0, &aThreadID);
    }
  }

#else 
  // Unix & Linux
  rlimit rlp;
  rlp.rlim_max = RLIM_INFINITY;
  if (n <= 1)
    rlp.rlim_cur = RLIM_INFINITY;
  else
    rlp.rlim_cur = Draw::Atoi(a[1]);
  CPU_LIMIT = rlp.rlim_cur;

  int status;
  status=setrlimit(RLIMIT_CPU,&rlp);
  if (status !=0)
    di << "status cpulimit setrlimit : " << status << "\n";

  // set signal handler to print a message before death
  struct sigaction act, oact;
  memset (&act, 0, sizeof(act));
  act.sa_handler = cpulimitSignalHandler;
  sigaction (SIGXCPU, &act, &oact);

  // cpulimit for elapsed time
  aTimer.Reset();
  aTimer.Start();
  pthread_t cpulimitThread;
  if (aFirst) // Launch the thread only at the 1st call.
  {
    aFirst = 0;
    pthread_create(&cpulimitThread, NULL, CpuFunc, NULL);
  }
#endif
  return 0;
}


//=======================================================================
//function : mallochook
//purpose  : 
//=======================================================================

static Standard_Integer mallochook(Draw_Interpretor& di, Standard_Integer n,
                                   const char** a)
{
  if (n < 2)
  {
    di << "\
usage: mallochook cmd\n\
where cmd is one of:\n\
  set [<op>]      - set callback to malloc/free; op is one of the following:\n\
                    0 - set callback to NULL,\n\
                    1 - set callback OSD_MAllocHook::CollectBySize (default)\n\
                    2 - set callback OSD_MAllocHook::LogFileHandler\n\
  reset           - reset the CollectBySize handler\n\
  report1 [<outfile>]\n\
                  - write report from CollectBySize handler in <outfile>\n\
  open [<logfile>]\n\
                  - open file for writing the log with LogFileHandler\n\
  close           - close the log file with LogFileHandler\n\
  report2 [<flag>] [<logfile>] [<outfile>]\n\
                  - scan <logfile> written with LogFileHandler\n\
                    and make synthesized report in <outfile>; <flag> can be:\n\
                    0 - simple stats by sizes (default),\n\
                    1 - with alive allocation numbers\n\
By default <logfile> is \"mem-log.txt\", <outfile> is \"mem-stat.txt\""
      << "\n";
    return 0;
  }
  if (strcmp(a[1], "set") == 0)
  {
    int aType = (n > 2 ? Draw::Atoi(a[2]) : 1);
    if (aType < 0 || aType > 2)
    {
      di << "unknown op of the command set\n";
      return 1;
    }
    else if (aType == 0)
    {
      OSD_MAllocHook::SetCallback(NULL);
      di << "callback is unset\n";
    }
    else if (aType == 1)
    {
      OSD_MAllocHook::SetCallback(OSD_MAllocHook::GetCollectBySize());
      di << "callback is set to CollectBySize\n";
    }
    else //if (aType == 2)
    {
      OSD_MAllocHook::SetCallback(OSD_MAllocHook::GetLogFileHandler());
      di << "callback is set to LogFileHandler\n";
    }
  }
  else if (strcmp(a[1], "reset") == 0)
  {
    OSD_MAllocHook::GetCollectBySize()->Reset();
    di << "CollectBySize handler is reset\n";
  }
  else if (strcmp(a[1], "open") == 0)
  {
    const char* aFileName = (n > 2 ? a[2] : "mem-log.txt");
    if (!OSD_MAllocHook::GetLogFileHandler()->Open(aFileName))
    {
      di << "cannot create file " << aFileName << " for writing\n";
      return 1;
    }
    di << "log file " << aFileName << " is opened for writing\n";
  }
  else if (strcmp(a[1], "close") == 0)
  {
    OSD_MAllocHook::GetLogFileHandler()->Close();
    di << "log file is closed\n";
  }
  else if (strcmp(a[1], "report1") == 0)
  {
    const char* aOutFile = "mem-stat.txt";
    if (n > 2)
      aOutFile = a[2];
    if (OSD_MAllocHook::GetCollectBySize()->MakeReport(aOutFile))
    {
      di << "report " << aOutFile << " has been created\n";
    }
    else
    {
      di << "cannot create report " << aOutFile << "\n";
      return 1;
    }
  }
  else if (strcmp(a[1], "report2") == 0)
  {
    Standard_Boolean includeAlive = Standard_False;
    const char* aLogFile = "mem-log.txt";
    const char* aOutFile = "mem-stat.txt";
    if (n > 2)
    {
      includeAlive = (Draw::Atoi(a[2]) != 0);
      if (n > 3)
      {
        aLogFile = a[3];
        if (n > 4)
          aOutFile = a[4];
      }
    }
    if (OSD_MAllocHook::LogFileHandler::MakeReport(aLogFile, aOutFile, includeAlive))
    {
      di << "report " << aOutFile << " has been created\n";
    }
    else
    {
      di << "cannot create report " << aOutFile << " from the log file "
        << aLogFile << "\n";
      return 1;
    }
  }
  else
  {
    di << "unrecognized command " << a[1] << "\n";
    return 1;
  }
  return 0;
}

//==============================================================================
//function : dlocale
//purpose  :
//==============================================================================

static int dlocale (Draw_Interpretor& di, Standard_Integer n, const char** argv)
{
  int category = LC_ALL;
  if (n > 1)
  {
    const char *cat = argv[1];
    if ( ! strcmp (cat, "LC_ALL") ) category = LC_ALL;
    else if ( ! strcmp (cat, "LC_COLLATE") ) category = LC_COLLATE;
    else if ( ! strcmp (cat, "LC_CTYPE") ) category = LC_CTYPE;
    else if ( ! strcmp (cat, "LC_MONETARY") ) category = LC_MONETARY;
    else if ( ! strcmp (cat, "LC_NUMERIC") ) category = LC_NUMERIC;
    else if ( ! strcmp (cat, "LC_TIME") ) category = LC_TIME;
    else 
    {
      cout << "Error: cannot recognize argument " << cat << " as one of LC_ macros" << endl;
      return 1;
    }
  }
  const char* locale = (n > 2 ? argv[2] : NULL);
  const char* result = setlocale (category, locale);
  if (result)
    di << result;
  else 
    cout << "Error: unsupported locale specification: " << locale << endl;
  return 0;
}

//==============================================================================
//function : dmeminfo
//purpose  :
//==============================================================================

static int dmeminfo (Draw_Interpretor& theDI,
                     Standard_Integer  theArgNb,
                     const char**      theArgVec)
{
  OSD_MemInfo aMemInfo;
  if (theArgNb <= 1)
  {
    theDI << aMemInfo.ToString();
    return 0;
  }

  for (Standard_Integer anIter = 1; anIter < theArgNb; ++anIter)
  {
    TCollection_AsciiString anArg (theArgVec[anIter]);
    anArg.LowerCase();
    if (anArg == "virt" || anArg == "v")
    {
      theDI << Standard_Real (aMemInfo.Value (OSD_MemInfo::MemVirtual)) << " ";
    }
    else if (anArg == "heap" || anArg == "h")
    {
      theDI << Standard_Real (aMemInfo.Value (OSD_MemInfo::MemHeapUsage)) << " ";
    }
    else if (anArg == "wset" || anArg == "w")
    {
      theDI << Standard_Real (aMemInfo.Value (OSD_MemInfo::MemWorkingSet)) << " ";
    }
    else if (anArg == "wsetpeak")
    {
      theDI << Standard_Real (aMemInfo.Value (OSD_MemInfo::MemWorkingSetPeak)) << " ";
    }
    else if (anArg == "swap")
    {
      theDI << Standard_Real (aMemInfo.Value (OSD_MemInfo::MemSwapUsage)) << " ";
    }
    else if (anArg == "swappeak")
    {
      theDI << Standard_Real (aMemInfo.Value (OSD_MemInfo::MemSwapUsagePeak)) << " ";
    }
    else if (anArg == "private")
    {
      theDI << Standard_Real (aMemInfo.Value (OSD_MemInfo::MemPrivate)) << " ";
    }
    else
    {
      std::cerr << "Unknown argument '" << theArgVec[anIter] << "'!\n";
    }
  }
  theDI << "\n";
  return 0;
}

//==============================================================================
//function : dperf
//purpose  :
//==============================================================================

static int dperf (Draw_Interpretor& theDI, Standard_Integer theArgNb, const char** theArgVec)
{
  // reset if argument is provided and it is not '0'
  int reset = (theArgNb > 1 ? theArgVec[1][0] != '0' && theArgVec[1][0] != '\0' : 0);
  char buffer[25600];
  perf_sprint_all_meters (buffer, 25600 - 1, reset);
  theDI << buffer;
  return 0;
}

//==============================================================================
//function : dsetsignal
//purpose  :
//==============================================================================

static int dsetsignal (Draw_Interpretor& theDI, Standard_Integer theArgNb, const char** theArgVec)
{
  // arm FPE handler if argument is provided and its first symbol is not '0'
  // or if environment variable CSF_FPE is set and its first symbol is not '0'
  bool setFPE = false;
  if (theArgNb > 1)
  {
    setFPE = (theArgVec[1][0] == '1' || theArgVec[1][0] == 't');
  }
  else
  {
    OSD_Environment aEnv ("CSF_FPE");
    TCollection_AsciiString aEnvStr = aEnv.Value();
    setFPE = (! aEnvStr.IsEmpty() && aEnvStr.Value(1) != '0');
  }
  OSD::SetSignal (setFPE);
  theDI << "Signal handlers are set, with FPE " << (setFPE ? "armed" : "disarmed"); 
  return 0;
}

//==============================================================================
//function : dtracelevel
//purpose  :
//==============================================================================

static int dtracelevel (Draw_Interpretor& theDI,
                        Standard_Integer  theArgNb,
                        const char**      theArgVec)
{
  Message_Gravity aLevel = Message_Info;
  if (theArgNb < 1 || theArgNb > 2)
  {
    std::cout << "Error: wrong number of arguments! See usage:\n";
    theDI.PrintHelp (theArgVec[0]);
    return 1;
  }
  else if (theArgNb == 2)
  {
    TCollection_AsciiString aVal (theArgVec[1]);
    aVal.LowerCase();
    if (aVal == "trace")
    {
      aLevel = Message_Trace;
    }
    else if (aVal == "info")
    {
      aLevel = Message_Info;
    }
    else if (aVal == "warn"
          || aVal == "warning")
    {
      aLevel = Message_Warning;
    }
    else if (aVal == "alarm")
    {
      aLevel = Message_Alarm;
    }
    else if (aVal == "fail")
    {
      aLevel = Message_Fail;
    }
    else
    {
      std::cout << "Error: unknown gravity '" << theArgVec[1] << "'!\n";
      return 1;
    }
  }

  Handle(Message_Messenger) aMessenger = Message::DefaultMessenger();
  if (aMessenger.IsNull())
  {
    std::cout << "Error: default messenger is unavailable!\n";
    return 1;
  }

  Message_SequenceOfPrinters& aPrinters = aMessenger->ChangePrinters();
  if (aPrinters.Length() < 1)
  {
    std::cout << "Error: no printers registered in default Messenger!\n";
    return 0;
  }

  for (Standard_Integer aPrinterIter = 1; aPrinterIter <= aPrinters.Length(); ++aPrinterIter)
  {
    Handle(Message_Printer)& aPrinter = aPrinters.ChangeValue (aPrinterIter);
    if (theArgNb == 1)
    {
      if (aPrinterIter == 1)
      {
        aLevel = aPrinter->GetTraceLevel();
      }
      else if (aLevel == aPrinter->GetTraceLevel())
      {
        continue;
      }

      switch (aPrinter->GetTraceLevel())
      {
        case Message_Trace:   theDI << "trace"; break;
        case Message_Info:    theDI << "info";  break;
        case Message_Warning: theDI << "warn";  break;
        case Message_Alarm:   theDI << "alarm"; break;
        case Message_Fail:    theDI << "fail";  break;
      }
      continue;
    }

    aPrinter->SetTraceLevel (aLevel);
  }

  return 0;
}

void Draw::BasicCommands(Draw_Interpretor& theCommands)
{
  static Standard_Boolean Done = Standard_False;
  if (Done) return;
  Done = Standard_True;

  ios::sync_with_stdio();

  const char* g = "DRAW General Commands";

  theCommands.Add("batch", "returns 1 in batch mode",
		  __FILE__,ifbatch,g);
  theCommands.Add("spy","spy [file], Save commands in file. no file close",
		  __FILE__,spy,g);
  theCommands.Add("wait","wait [time(10)], wait time seconds",
		  __FILE__,Draw_wait,g);
  theCommands.Add("cpulimit","cpulimit [nbseconds], no args remove limits",
		  __FILE__,cpulimit,g);
  theCommands.Add("chrono","chrono [ name start/stop/reset/show]",
		  __FILE__,chronom,g);
  theCommands.Add("dchrono","dchrono [ name start/stop/reset/show]",
		  __FILE__,dchronom,g);
  theCommands.Add("mallochook",
                  "debug memory allocation/deallocation, w/o args for help",
                  __FILE__, mallochook, g);
  theCommands.Add ("meminfo",
    "meminfo [virt|v] [heap|h] [wset|w] [wsetpeak] [swap] [swappeak] [private]"
    " : memory counters for this process",
	  __FILE__, dmeminfo, g);
  theCommands.Add("dperf","dperf [reset] -- show performance counters, reset if argument is provided",
		  __FILE__,dperf,g);
  theCommands.Add("dsetsignal","dsetsignal [fpe=0] -- set OSD signal handler, with FPE option if argument is given",
		  __FILE__,dsetsignal,g);

  // Logging commands; note that their names are hard-coded in the code
  // of Draw_Interpretor, thus should not be changed without update of that code!
  theCommands.Add("dlog", "manage logging of commands and output; run without args to get help",
		  __FILE__,dlog,g);
  theCommands.Add("decho", "switch on / off echo of commands to cout; run without args to get help",
		  __FILE__,decho,g);
  theCommands.Add("dtracelevel", "dtracelevel [trace|info|warn|alarm|fail]",
                  __FILE__, dtracelevel, g);

  theCommands.Add("dbreak", "raises Tcl exception if user has pressed Control-Break key",
		  __FILE__,dbreak,g);
  theCommands.Add("dversion", "provides information on OCCT build configuration (version, compiler, OS, C library, etc.)",
		  __FILE__,dversion,g);
  theCommands.Add("dlocale", "set and / or query locate of C subsystem (function setlocale())",
		  __FILE__,dlocale,g);
}