logstream.h

// ---------------------------------------------------------------------
//
// Copyright (C) 1998 - 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_logstream_h
#define dealii_logstream_h

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

#include <deal.II/base/exceptions.h>
#include <deal.II/base/smartpointer.h>
#include <deal.II/base/subscriptor.h>
#include <deal.II/base/thread_local_storage.h>

#include <cmath>
#include <map>
#include <memory>
#include <sstream>
#include <stack>
#include <string>


DEAL_II_NAMESPACE_OPEN

class LogStream : public Subscriptor
{
public:
  class Prefix
  {
  public:
    Prefix(const std::string &text);

    Prefix(const std::string &text, LogStream &stream);

    ~Prefix();

  private:
    SmartPointer<LogStream, LogStream::Prefix> stream;
  };


  LogStream();


  ~LogStream() override;


  void
  attach(std::ostream &                o,
         const bool                    print_job_id = true,
         const std::ios_base::fmtflags flags        = std::ios::showpoint |
                                               std::ios::left);


  void
  detach();


  std::ostream &
  get_console();


  std::ostream &
  get_file_stream();


  bool
  has_file() const;


  const std::string &
  get_prefix() const;


  void
  push(const std::string &text);


  void
  pop();


  unsigned int
  depth_console(const unsigned int n);


  unsigned int
  depth_file(const unsigned int n);


  bool
  log_thread_id(const bool flag);


  std::streamsize
  precision(const std::streamsize prec);


  std::streamsize
  width(const std::streamsize wide);


  std::ios::fmtflags
  flags(const std::ios::fmtflags f);


  LogStream &
  operator<<(std::ostream &(*p)(std::ostream &));


  std::size_t
  memory_consumption() const;

private:
  std::stack<std::string> &
  get_prefixes() const;

  mutable Threads::ThreadLocalStorage<std::stack<std::string>> prefixes;

  std::ostream *std_out;

  std::ostream *file;

  unsigned int std_depth;

  unsigned int file_depth;

  bool print_thread_id;

  bool at_newline;

  void
  print_line_head();

  std::ostringstream &
  get_stream();

  Threads::ThreadLocalStorage<std::shared_ptr<std::ostringstream>> outstreams;

  template <typename T>
  friend LogStream &
  operator<<(LogStream &log, const T &t);
};


/* ----------------------------- Inline functions and templates ----------------
 */


template <typename T>
inline LogStream &
operator<<(LogStream &log, const T &t)
{
  // print to the internal stringstream
  log.get_stream() << t;
  return log;
}



extern LogStream deallog;



DEAL_II_NAMESPACE_CLOSE

#endif