LArBadChannelParser.h

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/*
  Copyright (C) 2002-2025 CERN for the benefit of the ATLAS collaboration
*/
 
#ifndef LArBadChannelParser_H
#define LArBadChannelParser_H
 
#include "GaudiKernel/MsgStream.h"
#include <fstream>
 
class LArBadChannelParser
{
public:
 
    LArBadChannelParser(
        const std::string& filename, MsgStream* const log, 
        unsigned int numInts, int numStrings, unsigned int firstWildcard = 0);
 
    virtual ~LArBadChannelParser();
 
    bool fileStatusGood() const;
 
    template<typename T>
    std::vector< std::pair<std::vector<int>, std::vector<T> > > parseFile();
 
private:
 
    // Can not construct a parser without giving filename or MsgStream.
    LArBadChannelParser();
 
    std::vector<int> getIdFields(const std::vector<std::string>& words);
    std::vector<std::string> parseLine(std::string& line) const;
 
    template<typename T> 
    bool stringToNumber(T& theNumber, const std::string& theStr) const;
 
    template<typename T> 
    bool convertStrings(std::vector<T>& result, const std::vector<std::string>::const_iterator begin, 
        const std::vector<std::string>::const_iterator end) const;
 
    std::ifstream m_fin;            //to read the file
    unsigned int m_linenumber;      //line number currently being parsed
    const std::string m_filename;
    MsgStream* const m_log;
 
    const unsigned int m_numInts;       //the number of integers required to represent the Identifier(s)
    const int m_numStrings;         //the number of strings required to represent the status
    const unsigned int m_firstWildcard; // The first admissible position for a wildcard ('*')
                        // The counting is from 1, i.e. first  = 1
                        // If zero, then wildcards are not allowed
};
 
inline bool LArBadChannelParser::fileStatusGood() const
{
    return m_fin.good();
}
 
template<typename T>
inline std::vector< std::pair<std::vector<int>, std::vector<T> > > LArBadChannelParser::parseFile()
{
  typedef std::pair< std::vector<int>, std::vector<T> > LineData;
  std::vector<LineData> result;
 
  if(!fileStatusGood())
  {
    (*m_log) << MSG::ERROR << "LArBadChannelParser - Could not open file: " << m_filename << endmsg;
    return result;  //empty result
  }
 
  while(true)
  {
    std::string line;
    std::getline(m_fin, line);
    if(!fileStatusGood())
      break;    // loop termination at end of file
    ++m_linenumber;
    std::vector<std::string> input = parseLine(line);
 
    if(input.size() < m_numInts + std::abs(m_numStrings)) // if line is too short, skip it
    {
      if(input.size() != 0) // complain only for non-empty lines
        {(*m_log) << MSG::WARNING << "LArBadChannelParser REJECTED line " << m_linenumber \
          << " -\t not enough parameters given: " << input.size() << endmsg;}
      continue;
    }
 
    LineData parsedData;
 
    parsedData.first = getIdFields(input);
    if(parsedData.first.size() == 0)
      continue; // getIdFields failed, with error message. Skip this line.
 
    const std::vector<std::string>::const_iterator start = input.begin() + m_numInts;
    const std::vector<std::string>::const_iterator stop = \
      (m_numStrings < 0) ? static_cast<const std::vector<std::string>::const_iterator>(input.end()) : (start + m_numStrings);
 
    if(stop > start)
    { 
      if(!convertStrings<T>(parsedData.second, start, stop))
        continue; //convertStrings failed with error message. Skip this line.
    }
 
    if(stop < input.end())
      (*m_log) << MSG::WARNING << "LArBadChannelParser IGNORED unexpected input on line " << m_linenumber << "." << endmsg;
 
    result.push_back(std::move(parsedData));
    (*m_log) << MSG::VERBOSE << "LArBadChannelParser ACCEPTED line " << m_linenumber << " -\t " << line << endmsg;
  }
 
  (*m_log) << MSG::DEBUG << "LArBadChannelParser - Parsed " << m_linenumber << " lines in file '" << m_filename << "'." << endmsg;
  return result;
}
 
// The convertStrings function reads the elements in the input line after the integer part, 
// and converts them to type T. The code can be easily extended by adding specialized template functions
// to convert the elements to any desired type. The default template function below will work for any
// standard C++ numeric type, and the specialized template function below that works for the trivial case
// where T is string type.
 
template<typename T> //works for any standard C++ numeric type 
inline bool LArBadChannelParser::convertStrings(std::vector<T>& result, 
  const std::vector<std::string>::const_iterator begin, const std::vector<std::string>::const_iterator end) const
{
  result.clear();
  result.reserve(static_cast<unsigned int>(end - begin));
  for(std::vector<std::string>::const_iterator iter = begin; iter != end; ++iter)
  {
    T element;
    if(stringToNumber<T>(element, *iter))
      result.push_back(element);
    else
    {
      (*m_log) << MSG::WARNING << "LArBadChannelParser REJECTED line " << m_linenumber \
        << " -\t failed to extract status." << endmsg;
      return false;
    }
  }
  return true;
}
 
//trivial case: convert string to string
template<>
inline bool LArBadChannelParser::convertStrings(std::vector<std::string>& result, 
  const std::vector<std::string>::const_iterator begin, const std::vector<std::string>::const_iterator end) const
{
  result.assign(begin, end);
  return true;
}
 
//works for any built-in numeric C++ type
template<typename T>
inline bool LArBadChannelParser::stringToNumber(T& theNumber, const std::string& theString) const
{
        std::istringstream iss(theString);
        //return !(iss >> std::dec >> theNumber).fail() && (static_cast<int>(theString.size()) ==  iss.tellg());
        return !(iss >> std::dec >> theNumber).fail();
       //the second condition checks for invalid input of the form "123abc"
}
 
#endif  //end of #ifndef LArBadChannelParser_H