path_search.h

// ---------------------------------------------------------------------
//
// Copyright (C) 2005 - 2019 by the deal.II authors
//
// This file is part of the deal.II library.
//
// The deal.II library is free software; you can use it, redistribute
// it, and/or modify it under the terms of the GNU Lesser General
// Public License as published by the Free Software Foundation; either
// version 2.1 of the License, or (at your option) any later version.
// The full text of the license can be found in the file LICENSE.md at
// the top level directory of deal.II.
//
// ---------------------------------------------------------------------

#ifndef dealii_path_search_h
#define dealii_path_search_h


#include <deal.II/base/config.h>

#include <deal.II/base/exceptions.h>

#include <fstream>
#include <map>
#include <memory>
#include <string>
#include <vector>


DEAL_II_NAMESPACE_OPEN

class PathSearch
{
public:
  enum Position
  {
    back,
    front,
    after_none
  };

  PathSearch(const std::string &cls, const unsigned int debug = 0);

  std::string
  find(const std::string &filename, const char *open_mode = "r");

  std::string
  find(const std::string &filename,
       const std::string &suffix,
       const char *       open_mode = "r");

  template <class StreamType>
  void
  show(StreamType &stream) const;

  static void
  add_class(const std::string &cls);

  void
  add_path(const std::string &path, Position pos = back);

  void
  add_suffix(const std::string &suffix, Position pos = back);

  DeclException1(ExcNoClass,
                 std::string,
                 << "The class " << arg1
                 << " must be registered before referring it in PathSearch.");
  DeclException2(ExcFileNotFound,
                 std::string,
                 std::string,
                 << "The file \"" << arg1 << "\" was not found in the path for "
                 << "files of class " << arg2 << ".");

private:
  using map_type = std::map<std::string, std::vector<std::string>>::value_type;

  static void
  initialize_classes();

  static std::vector<std::string> &
  get_path_list(const std::string &cls);

  static std::vector<std::string> &
  get_suffix_list(const std::string &cls);

  const std::string cls;

  static std::map<std::string, std::vector<std::string>> path_lists;

  static std::map<std::string, std::vector<std::string>> suffix_lists;

  std::vector<std::string> &my_path_list;

  std::vector<std::string> &my_suffix_list;

  const unsigned int debug;

  static std::string empty;
};


/* ----------------------------- inline functions ------------------------- */


template <class StreamType>
inline void
PathSearch::show(StreamType &out) const
{
  out << "DEAL_II_" << cls << "PATH=\"";
  bool first = true;
  for (const auto &p : my_path_list)
    {
      if (!first)
        out << ':';
      out << p;
      first = false;
    }
  out << '"' << std::endl << " Suffixes";
  for (const auto &s : my_suffix_list)
    out << " \"" << s << '"';
  out << std::endl;
}

DEAL_II_NAMESPACE_CLOSE

#endif