PyROOTTFilePythonize.cxx

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/*
  Copyright (C) 2002-2020 CERN for the benefit of the ATLAS collaboration
*/
// stdlib includes
#include <stdlib.h>
#include <stdio.h>
 
#include "TFile.h"
 
// local includes
#include "RootUtils/PyROOTTFilePythonize.h"
 
namespace RootUtils {
 
PyBytes::PyBytes(size_t buf_sz) : 
  sz(buf_sz>0?buf_sz:0), 
  buf(sz)
{
}
 
PyBytes::~PyBytes() 
{
}
 
PyBytes::PyBytes(const PyBytes& rhs) : 
  sz(rhs.sz), 
  buf(rhs.buf)
{
}
 
PyBytes&
PyBytes::operator=(const PyBytes& rhs)
{
  if (this != &rhs) {
    this->sz = rhs.sz;
    this->buf = rhs.buf;
  }
  return *this;
}
 
Long64_t
_pythonize_tell_root_file(TFile* f)
{
  if (f) {
    return f->GetRelOffset();
  }
  fprintf (stderr, 
           "::RootUtils::_pythonize_tell_root_file got a NULL TFile ptr!\n");
  return 0;
}
 
PyBytes
_pythonize_read_root_file(TFile* f, Int_t len)
{
  if (!f) {
    //err
    return PyBytes(0);
  }
 
  Long64_t totsz  = f->GetSize();
  Long64_t curpos = _pythonize_tell_root_file(f);
  Long64_t remain = totsz - curpos;
  remain = (remain>0) ? remain : 0;
 
  len = (len>remain) ? remain : len;
  PyBytes buf(len);
  if (f->ReadBuffer((char*)buf.buf.data(), buf.sz)) {
    //err
    return PyBytes(0);
  }
 
  f->Seek(buf.sz + curpos);
  return buf;
}
 
} //> namespace RootUtils