//  boost progress.hpp header file  ------------------------------------------//

 //  Copyright Beman Dawes 1994-99.  Distributed under the Boost

 //  Software License, Version 1.0. (See accompanying file

 //  LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)

 //  See http://www.boost.org/libs/timer for documentation.

 //  Revision History

 //   1 Dec 01  Add leading progress display strings (suggested by Toon Knapen)

 //  20 May 01  Introduce several static_casts<> to eliminate warning messages

 //             (Fixed by Beman, reported by Herve Bronnimann)

 //  12 Jan 01  Change to inline implementation to allow use without library

 //             builds. See docs for more rationale. (Beman Dawes) 

 //  22 Jul 99  Name changed to .hpp

 //  16 Jul 99  Second beta

 //   6 Jul 99  Initial boost version

 #ifndef BOOST_PROGRESS_HPP

 #define BOOST_PROGRESS_HPP

 #include <boost/timer.hpp>

 #include <boost/utility.hpp>  // for noncopyable

 #include <boost/cstdint.hpp>  // for uintmax_t

 #include <iostream>           // for ostream, cout, etc

 #include <string>             // for string

 namespace boost {

 //  progress_timer  ----------------------------------------------------------//

 //  A progress_timer behaves like a timer except that the destructor displays

 //  an elapsed time message at an appropriate place in an appropriate form.

 class progress_timer : public timer, private noncopyable

 {

  public:

   explicit progress_timer( std::ostream & os = std::cout )

      // os is hint; implementation may ignore, particularly in embedded systems

      : m_os(os) {}

   ~progress_timer()

   {

   //  A) Throwing an exception from a destructor is a Bad Thing.

   //  B) The progress_timer destructor does output which may throw.

   //  C) A progress_timer is usually not critical to the application.

   //  Therefore, wrap the I/O in a try block, catch and ignore all exceptions.

     try

     {

       // use istream instead of ios_base to workaround GNU problem (Greg Chicares)

       std::istream::fmtflags old_flags = m_os.setf( std::istream::fixed,

                                                    std::istream::floatfield );

       std::streamsize old_prec = m_os.precision( 2 );

       m_os << elapsed() << " s\n" // "s" is System International d'Unités std

                         << std::endl;

       m_os.flags( old_flags );

       m_os.precision( old_prec );

     }

     catch (...) {} // eat any exceptions

   } // ~progress_timer

  private:

   std::ostream & m_os;

 };

 //  progress_display  --------------------------------------------------------//

 //  progress_display displays an appropriate indication of 

 //  progress at an appropriate place in an appropriate form.

 // NOTE: (Jan 12, 2001) Tried to change unsigned long to boost::uintmax_t, but

 // found some compilers couldn't handle the required conversion to double.

 // Reverted to unsigned long until the compilers catch up. 

 class progress_display : private noncopyable

 {

  public:

   explicit progress_display( unsigned long expected_count,

                              std::ostream & os = std::cout,

                              const std::string & s1 = "\n", //leading strings

                              const std::string & s2 = "",

                              const std::string & s3 = "" )

    // os is hint; implementation may ignore, particularly in embedded systems

    : m_os(os), m_s1(s1), m_s2(s2), m_s3(s3) { restart(expected_count); }

   void           restart( unsigned long expected_count )

   //  Effects: display appropriate scale

   //  Postconditions: count()==0, expected_count()==expected_count

   {

     _count = _next_tic_count = _tic = 0;

     _expected_count = expected_count;

     m_os << m_s1 << "0%   10   20   30   40   50   60   70   80   90   100%\n"

          << m_s2 << "|----|----|----|----|----|----|----|----|----|----|"

          << std::endl  // endl implies flush, which ensures display

          << m_s3;

     if ( !_expected_count ) _expected_count = 1;  // prevent divide by zero

   } // restart

   unsigned long  operator+=( unsigned long increment )

   //  Effects: Display appropriate progress tic if needed.

   //  Postconditions: count()== original count() + increment

   //  Returns: count().

   {

     if ( (_count += increment) >= _next_tic_count ) { display_tic(); }

     return _count;

   }

   unsigned long  operator++()           { return operator+=( 1 ); }

   unsigned long  count() const          { return _count; }

   unsigned long  expected_count() const { return _expected_count; }

   private:

   std::ostream &     m_os;  // may not be present in all imps

   const std::string  m_s1;  // string is more general, safer than 

   const std::string  m_s2;  //  const char *, and efficiency or size are

   const std::string  m_s3;  //  not issues

   unsigned long _count, _expected_count, _next_tic_count;

   unsigned int  _tic;

   void display_tic()

   {

     // use of floating point ensures that both large and small counts

     // work correctly.  static_cast<>() is also used several places

     // to suppress spurious compiler warnings. 

     unsigned int tics_needed =

       static_cast<unsigned int>(

         (static_cast<double>(_count)/_expected_count)*50.0 );

     do { m_os << '*' << std::flush; } while ( ++_tic < tics_needed );

     _next_tic_count = 

       static_cast<unsigned long>((_tic/50.0)*_expected_count);

     if ( _count == _expected_count ) {

       if ( _tic < 51 ) m_os << '*';

       m_os << std::endl;

       }

   } // display_tic

 };

 } // namespace boost

 #endif  // BOOST_PROGRESS_HPP