logstream.h

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// ------------------------------------------------------------------------
//
// SPDX-License-Identifier: LGPL-2.1-or-later
// Copyright (C) 1998 - 2024 by the deal.II authors
//
// This file is part of the deal.II library.
//
// Part of the source code is dual licensed under Apache-2.0 WITH
// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
// governing the source code and code contributions can be found in
// LICENSE.md and CONTRIBUTING.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/enable_observer_pointer.h>
#include <deal.II/base/exceptions.h>
#include <deal.II/base/observer_pointer.h>
#include <deal.II/base/thread_local_storage.h>
 
#include <cmath>
#include <memory>
#include <sstream>
#include <stack>
#include <string>
 
 
DEAL_II_NAMESPACE_OPEN
 
class LogStream : public EnableObserverPointer
{
public:
  class Prefix
  {
  public:
    Prefix(const std::string &text);
 
    Prefix(const std::string &text, LogStream &stream);
 
    ~Prefix();
 
  private:
    ObserverPointer<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::thread::id parent_thread;
 
  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