TBufferText.cxx

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// $Id$
// Author: Sergey Linev  21.12.2017

/*************************************************************************
 * Copyright (C) 1995-2017, Rene Brun and Fons Rademakers.               *
 * All rights reserved.                                                  *
 *                                                                       *
 * For the licensing terms see $ROOTSYS/LICENSE.                         *
 * For the list of contributors see $ROOTSYS/README/CREDITS.             *
 *************************************************************************/

/**
\class TBufferText
\ingroup IO

Base class for text-based streamers like TBufferJSON or TBufferXML
Special actions list will use methods, introduced in this class.

Idea to have equivalent methods names in TBufferFile and TBufferText, that
actions list for both are the same.
*/

#include "TBufferText.h"

#include "TStreamerInfo.h"
#include "TStreamerElement.h"
#include "TStreamerInfoActions.h"
#include "TFile.h"
#include "TVirtualMutex.h"
#include "TInterpreter.h"
#include "TROOT.h"
#include "TExMap.h"
#include "TError.h"

ClassImp(TBufferText);

const char *TBufferText::fgFloatFmt = "%e";
const char *TBufferText::fgDoubleFmt = "%.14e";

////////////////////////////////////////////////////////////////////////////////
/// Default constructor

TBufferText::TBufferText() : TBufferIO()
{
}

////////////////////////////////////////////////////////////////////////////////
/// Normal constructor

TBufferText::TBufferText(TBuffer::EMode mode, TObject *parent) : TBufferIO(mode)
{
   fBufSize = 1000000000;

   SetParent(parent);
   SetBit(kCannotHandleMemberWiseStreaming);
}

////////////////////////////////////////////////////////////////////////////////
/// destructor

TBufferText::~TBufferText()
{
}

////////////////////////////////////////////////////////////////////////////////
/// Read one collection of objects from the buffer using the StreamerInfoLoopAction.
/// The collection needs to be a split TClonesArray or a split vector of pointers.

Int_t TBufferText::ApplySequence(const TStreamerInfoActions::TActionSequence &sequence, void *obj)
{
   TVirtualStreamerInfo *info = sequence.fStreamerInfo;
   IncrementLevel(info);

   if (gDebug) {
      // loop on all active members
      TStreamerInfoActions::ActionContainer_t::const_iterator end = sequence.fActions.end();
      for (TStreamerInfoActions::ActionContainer_t::const_iterator iter = sequence.fActions.begin(); iter != end;
           ++iter) {
         // Idea: Try to remove this function call as it is really needed only for JSON streaming.
         SetStreamerElementNumber((*iter).fConfiguration->fCompInfo->fElem, (*iter).fConfiguration->fCompInfo->fType);
         (*iter).PrintDebug(*this, obj);
         (*iter)(*this, obj);
      }
   } else {
      // loop on all active members
      TStreamerInfoActions::ActionContainer_t::const_iterator end = sequence.fActions.end();
      for (TStreamerInfoActions::ActionContainer_t::const_iterator iter = sequence.fActions.begin(); iter != end;
           ++iter) {
         // Idea: Try to remove this function call as it is really needed only for JSON streaming.
         SetStreamerElementNumber((*iter).fConfiguration->fCompInfo->fElem, (*iter).fConfiguration->fCompInfo->fType);
         (*iter)(*this, obj);
      }
   }
   DecrementLevel(info);
   return 0;
}

////////////////////////////////////////////////////////////////////////////////
/// Read one collection of objects from the buffer using the StreamerInfoLoopAction.
/// The collection needs to be a split TClonesArray or a split vector of pointers.

Int_t TBufferText::ApplySequenceVecPtr(const TStreamerInfoActions::TActionSequence &sequence, void *start_collection,
                                       void *end_collection)
{
   TVirtualStreamerInfo *info = sequence.fStreamerInfo;
   IncrementLevel(info);

   if (gDebug) {
      // loop on all active members
      TStreamerInfoActions::ActionContainer_t::const_iterator end = sequence.fActions.end();
      for (TStreamerInfoActions::ActionContainer_t::const_iterator iter = sequence.fActions.begin(); iter != end;
           ++iter) {
         // Idea: Try to remove this function call as it is really needed only for JSON streaming.
         SetStreamerElementNumber((*iter).fConfiguration->fCompInfo->fElem, (*iter).fConfiguration->fCompInfo->fType);
         (*iter).PrintDebug(
            *this, *(char **)start_collection); // Warning: This limits us to TClonesArray and vector of pointers.
         (*iter)(*this, start_collection, end_collection);
      }
   } else {
      // loop on all active members
      TStreamerInfoActions::ActionContainer_t::const_iterator end = sequence.fActions.end();
      for (TStreamerInfoActions::ActionContainer_t::const_iterator iter = sequence.fActions.begin(); iter != end;
           ++iter) {
         // Idea: Try to remove this function call as it is really needed only for JSON streaming.
         SetStreamerElementNumber((*iter).fConfiguration->fCompInfo->fElem, (*iter).fConfiguration->fCompInfo->fType);
         (*iter)(*this, start_collection, end_collection);
      }
   }
   DecrementLevel(info);
   return 0;
}

////////////////////////////////////////////////////////////////////////////////
/// Read one collection of objects from the buffer using the StreamerInfoLoopAction.

Int_t TBufferText::ApplySequence(const TStreamerInfoActions::TActionSequence &sequence, void *start_collection,
                                 void *end_collection)
{
   TVirtualStreamerInfo *info = sequence.fStreamerInfo;
   IncrementLevel(info);

   TStreamerInfoActions::TLoopConfiguration *loopconfig = sequence.fLoopConfig;
   if (gDebug) {

      // Get the address of the first item for the PrintDebug.
      // (Performance is not essential here since we are going to print to
      // the screen anyway).
      void *arr0 = loopconfig->GetFirstAddress(start_collection, end_collection);
      // loop on all active members
      TStreamerInfoActions::ActionContainer_t::const_iterator end = sequence.fActions.end();
      for (TStreamerInfoActions::ActionContainer_t::const_iterator iter = sequence.fActions.begin(); iter != end;
           ++iter) {
         // Idea: Try to remove this function call as it is really needed only for JSON streaming.
         SetStreamerElementNumber((*iter).fConfiguration->fCompInfo->fElem, (*iter).fConfiguration->fCompInfo->fType);
         (*iter).PrintDebug(*this, arr0);
         (*iter)(*this, start_collection, end_collection, loopconfig);
      }
   } else {
      // loop on all active members
      TStreamerInfoActions::ActionContainer_t::const_iterator end = sequence.fActions.end();
      for (TStreamerInfoActions::ActionContainer_t::const_iterator iter = sequence.fActions.begin(); iter != end;
           ++iter) {
         // Idea: Try to remove this function call as it is really needed only for JSON streaming.
         SetStreamerElementNumber((*iter).fConfiguration->fCompInfo->fElem, (*iter).fConfiguration->fCompInfo->fType);
         (*iter)(*this, start_collection, end_collection, loopconfig);
      }
   }
   DecrementLevel(info);
   return 0;
}

////////////////////////////////////////////////////////////////////////////////
/// Function called by the Streamer functions to serialize object at p
/// to buffer b. The optional argument info may be specified to give an
/// alternative StreamerInfo instead of using the default StreamerInfo
/// automatically built from the class definition.
/// For more information, see class TStreamerInfo.

Int_t TBufferText::WriteClassBuffer(const TClass *cl, void *pointer)
{
   // build the StreamerInfo if first time for the class
   TStreamerInfo *sinfo = (TStreamerInfo *)const_cast<TClass *>(cl)->GetCurrentStreamerInfo();
   if (!sinfo) {
      // Have to be sure between the check and the taking of the lock if the current streamer has changed
      R__LOCKGUARD(gInterpreterMutex);
      sinfo = (TStreamerInfo *)const_cast<TClass *>(cl)->GetCurrentStreamerInfo();
      if (!sinfo) {
         const_cast<TClass *>(cl)->BuildRealData(pointer);
         sinfo = new TStreamerInfo(const_cast<TClass *>(cl));
         const_cast<TClass *>(cl)->SetCurrentStreamerInfo(sinfo);
         const_cast<TClass *>(cl)->RegisterStreamerInfo(sinfo);
         if (gDebug > 0)
            Info("WriteClassBuffer", "Creating StreamerInfo for class: %s, version: %d", cl->GetName(),
                 cl->GetClassVersion());
         sinfo->Build();
      }
   } else if (!sinfo->IsCompiled()) {
      R__LOCKGUARD(gInterpreterMutex);
      // Redo the test in case we have been victim of a data race on fIsCompiled.
      if (!sinfo->IsCompiled()) {
         const_cast<TClass *>(cl)->BuildRealData(pointer);
         sinfo->BuildOld();
      }
   }

   // write the class version number and reserve space for the byte count
   UInt_t R__c = WriteVersion(cl, kTRUE);

   // NOTE: In the future Philippe wants this to happen via a custom action
   TagStreamerInfo(sinfo);
   ApplySequence(*(sinfo->GetWriteTextActions()), (char *)pointer);

   // write the byte count at the start of the buffer
   SetByteCount(R__c, kTRUE);

   if (gDebug > 2)
      Info("WriteClassBuffer", "class: %s version %d has written %d bytes", cl->GetName(), cl->GetClassVersion(),
           UInt_t(fBufCur - fBuffer) - R__c - (UInt_t)sizeof(UInt_t));
   return 0;
}

////////////////////////////////////////////////////////////////////////////////
/// Deserialize information from a buffer into an object.
///
/// Note: This function is called by the xxx::Streamer() functions in
/// rootcint-generated dictionaries.
/// This function assumes that the class version and the byte count
/// information have been read.
///
/// \param[in] version The version number of the class
/// \param[in] start   The starting position in the buffer b
/// \param[in] count   The number of bytes for this object in the buffer
///

Int_t TBufferText::ReadClassBuffer(const TClass *cl, void *pointer, Int_t version, UInt_t start, UInt_t count,
                                   const TClass *onFileClass)
{

   //---------------------------------------------------------------------------
   // The ondisk class has been specified so get foreign streamer info
   /////////////////////////////////////////////////////////////////////////////

   TStreamerInfo *sinfo = nullptr;
   if (onFileClass) {
      sinfo = (TStreamerInfo *)cl->GetConversionStreamerInfo(onFileClass, version);
      if (!sinfo) {
         Error("ReadClassBuffer",
               "Could not find the right streamer info to convert %s version %d into a %s, object skipped at offset %d",
               onFileClass->GetName(), version, cl->GetName(), Length());
         CheckByteCount(start, count, onFileClass);
         return 0;
      }
   }
   //---------------------------------------------------------------------------
   // Get local streamer info
   /////////////////////////////////////////////////////////////////////////////
   /// The StreamerInfo should exist at this point.

   else {
      R__LOCKGUARD(gInterpreterMutex);
      auto infos = cl->GetStreamerInfos();
      auto ninfos = infos->GetSize();
      if (version < -1 || version >= ninfos) {
         Error("ReadBuffer1", "class: %s, attempting to access a wrong version: %d, object skipped at offset %d",
               cl->GetName(), version, Length());
         CheckByteCount(start, count, cl);
         return 0;
      }
      sinfo = (TStreamerInfo *)infos->At(version);
      if (!sinfo) {
         // Unless the data is coming via a socket connection from with schema evolution
         // (tracking) was not enabled.  So let's create the StreamerInfo if it is the
         // one for the current version, otherwise let's complain ...
         // We could also get here if there old class version was '1' and the new class version is higher than 1
         // AND the checksum is the same.
         if (version == cl->GetClassVersion() || version == 1) {
            const_cast<TClass *>(cl)->BuildRealData(pointer);
            // This creation is alright since we just checked within the
            // current 'locked' section.
            sinfo = new TStreamerInfo(const_cast<TClass *>(cl));
            const_cast<TClass *>(cl)->RegisterStreamerInfo(sinfo);
            if (gDebug > 0)
               Info("ReadClassBuffer", "Creating StreamerInfo for class: %s, version: %d", cl->GetName(), version);
            sinfo->Build();
         } else if (version == 0) {
            // When the object was written the class was version zero, so
            // there is no StreamerInfo to be found.
            // Check that the buffer position corresponds to the byte count.
            CheckByteCount(start, count, cl);
            return 0;
         } else {
            Error("ReadClassBuffer",
                  "Could not find the StreamerInfo for version %d of the class %s, object skipped at offset %d",
                  version, cl->GetName(), Length());
            CheckByteCount(start, count, cl);
            return 0;
         }
      } else if (!sinfo->IsCompiled()) { // Note this read is protected by the above lock.
         // Streamer info has not been compiled, but exists.
         // Therefore it was read in from a file and we have to do schema evolution.
         const_cast<TClass *>(cl)->BuildRealData(pointer);
         sinfo->BuildOld();
      }
   }

   // Deserialize the object.
   ApplySequence(*(sinfo->GetReadTextActions()), (char *)pointer);
   if (sinfo->IsRecovered())
      count = 0;

   // Check that the buffer position corresponds to the byte count.
   CheckByteCount(start, count, cl);
   return 0;
}

////////////////////////////////////////////////////////////////////////////////
/// Deserialize information from a buffer into an object.
///
/// Note: This function is called by the xxx::Streamer()
/// functions in rootcint-generated dictionaries.
///

Int_t TBufferText::ReadClassBuffer(const TClass *cl, void *pointer, const TClass *onFileClass)
{
   // Read the class version from the buffer.
   UInt_t R__s = 0; // Start of object.
   UInt_t R__c = 0; // Count of bytes.
   Version_t version;

   if (onFileClass)
      version = ReadVersion(&R__s, &R__c, onFileClass);
   else
      version = ReadVersion(&R__s, &R__c, cl);

   Bool_t v2file = kFALSE;
   TFile *file = (TFile *)GetParent();
   if (file && file->GetVersion() < 30000) {
      version = -1; // This is old file
      v2file = kTRUE;
   }

   //---------------------------------------------------------------------------
   // The ondisk class has been specified so get foreign streamer info
   /////////////////////////////////////////////////////////////////////////////

   TStreamerInfo *sinfo = nullptr;
   if (onFileClass) {
      sinfo = (TStreamerInfo *)cl->GetConversionStreamerInfo(onFileClass, version);
      if (!sinfo) {
         Error("ReadClassBuffer",
               "Could not find the right streamer info to convert %s version %d into a %s, object skipped at offset %d",
               onFileClass->GetName(), version, cl->GetName(), Length());
         CheckByteCount(R__s, R__c, onFileClass);
         return 0;
      }
   }
   //---------------------------------------------------------------------------
   // Get local streamer info
   /////////////////////////////////////////////////////////////////////////////
   /// The StreamerInfo should exist at this point.

   else {
      TStreamerInfo *guess = (TStreamerInfo *)cl->GetLastReadInfo();
      if (guess && guess->GetClassVersion() == version) {
         sinfo = guess;
      } else {
         // The last one is not the one we are looking for.
         {
            R__LOCKGUARD(gInterpreterMutex);

            const TObjArray *infos = cl->GetStreamerInfos();
            Int_t infocapacity = infos->Capacity();
            if (infocapacity) {
               if (version < -1 || version >= infocapacity) {
                  Error("ReadClassBuffer",
                        "class: %s, attempting to access a wrong version: %d, object skipped at offset %d",
                        cl->GetName(), version, Length());
                  CheckByteCount(R__s, R__c, cl);
                  return 0;
               }
               sinfo = (TStreamerInfo *)infos->UncheckedAt(version);
               if (sinfo) {
                  if (!sinfo->IsCompiled()) {
                     // Streamer info has not been compiled, but exists.
                     // Therefore it was read in from a file and we have to do schema evolution?
                     R__LOCKGUARD(gInterpreterMutex);
                     const_cast<TClass *>(cl)->BuildRealData(pointer);
                     sinfo->BuildOld();
                  }
                  // If the compilation succeeded, remember this StreamerInfo.
                  // const_cast okay because of the lock on gInterpreterMutex.
                  if (sinfo->IsCompiled())
                     const_cast<TClass *>(cl)->SetLastReadInfo(sinfo);
               }
            }
         }

         if (!sinfo) {
            // Unless the data is coming via a socket connection from with schema evolution
            // (tracking) was not enabled.  So let's create the StreamerInfo if it is the
            // one for the current version, otherwise let's complain ...
            // We could also get here when reading a file prior to the introduction of StreamerInfo.
            // We could also get here if there old class version was '1' and the new class version is higher than 1
            // AND the checksum is the same.
            if (v2file || version == cl->GetClassVersion() || version == 1) {
               R__LOCKGUARD(gInterpreterMutex);

               // We need to check if another thread did not get here first
               // and did the StreamerInfo creation already.
               auto infos = cl->GetStreamerInfos();
               auto ninfos = infos->GetSize();
               if (!(version < -1 || version >= ninfos)) {
                  sinfo = (TStreamerInfo *)infos->At(version);
               }
               if (!sinfo) {
                  const_cast<TClass *>(cl)->BuildRealData(pointer);
                  sinfo = new TStreamerInfo(const_cast<TClass *>(cl));
                  sinfo->SetClassVersion(version);
                  const_cast<TClass *>(cl)->RegisterStreamerInfo(sinfo);
                  if (gDebug > 0)
                     Info("ReadClassBuffer", "Creating StreamerInfo for class: %s, version: %d", cl->GetName(),
                          version);
                  if (v2file) {
                     sinfo->Build();             // Get the elements.
                     sinfo->Clear("build");      // Undo compilation.
                     sinfo->BuildEmulated(file); // Fix the types and redo compilation.
                  } else {
                     sinfo->Build();
                  }
               }
            } else if (version == 0) {
               // When the object was written the class was version zero, so
               // there is no StreamerInfo to be found.
               // Check that the buffer position corresponds to the byte count.
               CheckByteCount(R__s, R__c, cl);
               return 0;
            } else {
               Error("ReadClassBuffer",
                     "Could not find the StreamerInfo for version %d of the class %s, object skipped at offset %d",
                     version, cl->GetName(), Length());
               CheckByteCount(R__s, R__c, cl);
               return 0;
            }
         }
      }
   }

   // deserialize the object
   ApplySequence(*(sinfo->GetReadTextActions()), (char *)pointer);
   if (sinfo->TStreamerInfo::IsRecovered())
      R__c = 0; // 'TStreamerInfo::' avoids going via a virtual function.

   // Check that the buffer position corresponds to the byte count.
   CheckByteCount(R__s, R__c, cl);

   if (gDebug > 2)
      Info("ReadClassBuffer", "for class: %s has read %d bytes", cl->GetName(), R__c);

   return 0;
}

////////////////////////////////////////////////////////////////////////////////
/// stream object to/from buffer

void TBufferText::StreamObject(void *obj, const std::type_info &typeinfo, const TClass * /* onFileClass */)
{
   StreamObject(obj, TClass::GetClass(typeinfo));
}

////////////////////////////////////////////////////////////////////////////////
/// stream object to/from buffer

void TBufferText::StreamObject(void *obj, const char *className, const TClass * /* onFileClass */)
{
   StreamObject(obj, TClass::GetClass(className));
}

void TBufferText::StreamObject(TObject *obj)
{
   // stream object to/from buffer

   StreamObject(obj, obj ? obj->IsA() : TObject::Class());
}

////////////////////////////////////////////////////////////////////////////////
/// read a Float16_t from the buffer

void TBufferText::ReadFloat16(Float_t *f, TStreamerElement * /*ele*/)
{
   ReadFloat(*f);
}

////////////////////////////////////////////////////////////////////////////////
/// read a Double32_t from the buffer

void TBufferText::ReadDouble32(Double_t *d, TStreamerElement * /*ele*/)
{
   ReadDouble(*d);
}

////////////////////////////////////////////////////////////////////////////////
/// Read a Double32_t from the buffer when the factor and minimun value have
/// been specified
/// see comments about Double32_t encoding at TBufferFile::WriteDouble32().
/// Currently TBufferText does not optimize space in this case.

void TBufferText::ReadWithFactor(Float_t *f, Double_t /* factor */, Double_t /* minvalue */)
{
   ReadFloat(*f);
}

////////////////////////////////////////////////////////////////////////////////
/// Read a Float16_t from the buffer when the number of bits is specified
/// (explicitly or not)
/// see comments about Float16_t encoding at TBufferFile::WriteFloat16().
/// Currently TBufferText does not optimize space in this case.

void TBufferText::ReadWithNbits(Float_t *f, Int_t /* nbits */)
{
   ReadFloat(*f);
}

////////////////////////////////////////////////////////////////////////////////
/// Read a Double32_t from the buffer when the factor and minimun value have
/// been specified
/// see comments about Double32_t encoding at TBufferFile::WriteDouble32().
/// Currently TBufferText does not optimize space in this case.

void TBufferText::ReadWithFactor(Double_t *d, Double_t /* factor */, Double_t /* minvalue */)
{
   ReadDouble(*d);
}

////////////////////////////////////////////////////////////////////////////////
/// Read a Double32_t from the buffer when the number of bits is specified
/// (explicitly or not)
/// see comments about Double32_t encoding at TBufferFile::WriteDouble32().
/// Currently TBufferText does not optimize space in this case.

void TBufferText::ReadWithNbits(Double_t *d, Int_t /* nbits */)
{
   ReadDouble(*d);
}

////////////////////////////////////////////////////////////////////////////////
/// write a Float16_t to the buffer

void TBufferText::WriteFloat16(Float_t *f, TStreamerElement * /*ele*/)
{
   WriteFloat(*f);
}

////////////////////////////////////////////////////////////////////////////////
/// write a Double32_t to the buffer

void TBufferText::WriteDouble32(Double_t *d, TStreamerElement * /*ele*/)
{
   WriteDouble(*d);
}

////////////////////////////////////////////////////////////////////////////////
/// Read array of Float16_t from buffer

Int_t TBufferText::ReadArrayFloat16(Float_t *&f, TStreamerElement * /*ele*/)
{
   return ReadArray(f);
}

////////////////////////////////////////////////////////////////////////////////
/// Read array of Double32_t from buffer

Int_t TBufferText::ReadArrayDouble32(Double_t *&d, TStreamerElement * /*ele*/)
{
   return ReadArray(d);
}

////////////////////////////////////////////////////////////////////////////////
/// Read array of Float16_t from buffer

Int_t TBufferText::ReadStaticArrayFloat16(Float_t *f, TStreamerElement * /*ele*/)
{
   return ReadStaticArray(f);
}

////////////////////////////////////////////////////////////////////////////////
/// Read array of Double32_t from buffer

Int_t TBufferText::ReadStaticArrayDouble32(Double_t *d, TStreamerElement * /*ele*/)
{
   return ReadStaticArray(d);
}

////////////////////////////////////////////////////////////////////////////////
/// read array of Float16_t from buffer

void TBufferText::ReadFastArrayFloat16(Float_t *f, Int_t n, TStreamerElement * /*ele*/)
{
   ReadFastArray(f, n);
}

////////////////////////////////////////////////////////////////////////////////
/// read array of Float16_t from buffer

void TBufferText::ReadFastArrayWithFactor(Float_t *f, Int_t n, Double_t /* factor */, Double_t /* minvalue */)
{
   ReadFastArray(f, n);
}

////////////////////////////////////////////////////////////////////////////////
/// read array of Float16_t from buffer

void TBufferText::ReadFastArrayWithNbits(Float_t *f, Int_t n, Int_t /*nbits*/)
{
   ReadFastArray(f, n);
}

////////////////////////////////////////////////////////////////////////////////
/// read array of Double32_t from buffer

void TBufferText::ReadFastArrayDouble32(Double_t *d, Int_t n, TStreamerElement * /*ele*/)
{
   ReadFastArray(d, n);
}

////////////////////////////////////////////////////////////////////////////////
/// read array of Double32_t from buffer

void TBufferText::ReadFastArrayWithFactor(Double_t *d, Int_t n, Double_t /* factor */, Double_t /* minvalue */)
{
   ReadFastArray(d, n);
}

////////////////////////////////////////////////////////////////////////////////
/// read array of Double32_t from buffer

void TBufferText::ReadFastArrayWithNbits(Double_t *d, Int_t n, Int_t /*nbits*/)
{
   ReadFastArray(d, n);
}
////////////////////////////////////////////////////////////////////////////////
/// Write array of Float16_t to buffer

void TBufferText::WriteArrayFloat16(const Float_t *f, Int_t n, TStreamerElement * /*ele*/)
{
   WriteArray(f, n);
}

////////////////////////////////////////////////////////////////////////////////
/// Write array of Double32_t to buffer

void TBufferText::WriteArrayDouble32(const Double_t *d, Int_t n, TStreamerElement * /*ele*/)
{
   WriteArray(d, n);
}

////////////////////////////////////////////////////////////////////////////////
/// Write array of Float16_t to buffer

void TBufferText::WriteFastArrayFloat16(const Float_t *f, Int_t n, TStreamerElement * /*ele*/)
{
   WriteFastArray(f, n);
}

////////////////////////////////////////////////////////////////////////////////
/// Write array of Double32_t to buffer

void TBufferText::WriteFastArrayDouble32(const Double_t *d, Int_t n, TStreamerElement * /*ele*/)
{
   WriteFastArray(d, n);
}

////////////////////////////////////////////////////////////////////////////////
/// Skip class version from I/O buffer.

void TBufferText::SkipVersion(const TClass *cl)
{
   ReadVersion(nullptr, nullptr, cl);
}

////////////////////////////////////////////////////////////////////////////////
/// Write data of base class.

void TBufferText::WriteBaseClass(void *start, TStreamerBase *elem)
{
   elem->WriteBuffer(*this, (char *)start);
}

////////////////////////////////////////////////////////////////////////////////
/// Read data of base class.

void TBufferText::ReadBaseClass(void *start, TStreamerBase *elem)
{
   elem->ReadBuffer(*this, (char *)start);
}

////////////////////////////////////////////////////////////////////////////////
/// method compress float string, excluding exp and/or move float point
///  - 1.000000e-01 -> 0.1
///  - 3.750000e+00 -> 3.75
///  - 3.750000e-03 -> 0.00375
///  - 3.750000e-04 -> 3.75e-4
///  - 1.100000e-10 -> 1.1e-10

void TBufferText::CompactFloatString(char *sbuf, unsigned len)
{
   char *pnt = nullptr, *exp = nullptr, *lastdecimal = nullptr, *s = sbuf;
   bool negative_exp = false;
   int power = 0;
   while (*s && --len) {
      switch (*s) {
      case '.': pnt = s; break;
      case 'E':
      case 'e': exp = s; break;
      case '-':
         if (exp)
            negative_exp = true;
         break;
      case '+': break;
      default: // should be digits from '0' to '9'
         if ((*s < '0') || (*s > '9'))
            return;
         if (exp)
            power = power * 10 + (*s - '0');
         else if (pnt && *s != '0')
            lastdecimal = s;
         break;
      }
      ++s;
   }
   if (*s)
      return; // if end-of-string was not found

   if (!exp) {
      // value without exponent like 123.4569000
      if (pnt) {
         if (lastdecimal)
            *(lastdecimal + 1) = 0;
         else
            *pnt = 0;
      }
   } else if (power == 0) {
      if (lastdecimal)
         *(lastdecimal + 1) = 0;
      else if (pnt)
         *pnt = 0;
   } else if (!negative_exp && pnt && exp && (exp - pnt > power)) {
      // this is case of value 1.23000e+02
      // we can move point and exclude exponent easily
      for (int cnt = 0; cnt < power; ++cnt) {
         char tmp = *pnt;
         *pnt = *(pnt + 1);
         *(++pnt) = tmp;
      }
      if (lastdecimal && (pnt < lastdecimal))
         *(lastdecimal + 1) = 0;
      else
         *pnt = 0;
   } else if (negative_exp && pnt && exp && (power < (s - exp))) {
      // this is small negative exponent like 1.2300e-02
      if (!lastdecimal)
         lastdecimal = pnt;
      *(lastdecimal + 1) = 0;
      // copy most significant digit on the point place
      *pnt = *(pnt - 1);

      for (char *pos = lastdecimal + 1; pos >= pnt; --pos)
         *(pos + power) = *pos;
      *(pnt - 1) = '0';
      *pnt = '.';
      for (int cnt = 1; cnt < power; ++cnt)
         *(pnt + cnt) = '0';
   } else if (pnt && exp) {
      // keep exponent, but non-significant zeros
      if (lastdecimal)
         pnt = lastdecimal + 1;
      // copy exponent sign
      *pnt++ = *exp++;
      if (*exp == '+')
         ++exp;
      else if (*exp == '-')
         *pnt++ = *exp++;
      // exclude zeros in the begin of exponent
      while (*exp == '0')
         ++exp;
      while (*exp)
         *pnt++ = *exp++;
      *pnt = 0;
   }
}

////////////////////////////////////////////////////////////////////////////////
/// set printf format for float/double members, default "%e"
/// to change format only for doubles, use SetDoubleFormat

void TBufferText::SetFloatFormat(const char *fmt)
{
   if (!fmt)
      fmt = "%e";
   fgFloatFmt = fmt;
   fgDoubleFmt = fmt;
}

////////////////////////////////////////////////////////////////////////////////
/// return current printf format for float members, default "%e"

const char *TBufferText::GetFloatFormat()
{
   return fgFloatFmt;
}

////////////////////////////////////////////////////////////////////////////////
/// set printf format for double members, default "%.14e"
/// use it after SetFloatFormat, which also overwrites format for doubles

void TBufferText::SetDoubleFormat(const char *fmt)
{
   if (!fmt)
      fmt = "%.14e";
   fgDoubleFmt = fmt;
}

////////////////////////////////////////////////////////////////////////////////
/// return current printf format for double members, default "%.14e"

const char *TBufferText::GetDoubleFormat()
{
   return fgDoubleFmt;
}

////////////////////////////////////////////////////////////////////////////////
/// convert float to string with configured format

const char *TBufferText::ConvertFloat(Float_t value, char *buf, unsigned len, Bool_t not_optimize)
{
   if (not_optimize) {
      snprintf(buf, len, fgFloatFmt, value);
   } else if ((value == std::nearbyint(value)) && (std::abs(value) < 1e15)) {
      snprintf(buf, len, "%1.0f", value);
   } else {
      snprintf(buf, len, fgFloatFmt, value);
      CompactFloatString(buf, len);
   }
   return buf;
}

////////////////////////////////////////////////////////////////////////////////
/// convert float to string with configured format

const char *TBufferText::ConvertDouble(Double_t value, char *buf, unsigned len, Bool_t not_optimize)
{
   if (not_optimize) {
      snprintf(buf, len, fgFloatFmt, value);
   } else if ((value == std::nearbyint(value)) && (std::abs(value) < 1e25)) {
      snprintf(buf, len, "%1.0f", value);
   } else {
      snprintf(buf, len, fgDoubleFmt, value);
      CompactFloatString(buf, len);
   }
   return buf;
}