Line data    Source code

       1             : // The libMesh Finite Element Library.
       2             : // Copyright (C) 2002-2025 Benjamin S. Kirk, John W. Peterson, Roy H. Stogner
       3             : 
       4             : // This library is free software; you can redistribute it and/or
       5             : // modify it under the terms of the GNU Lesser General Public
       6             : // License as published by the Free Software Foundation; either
       7             : // version 2.1 of the License, or (at your option) any later version.
       8             : 
       9             : // This library is distributed in the hope that it will be useful,
      10             : // but WITHOUT ANY WARRANTY; without even the implied warranty of
      11             : // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
      12             : // Lesser General Public License for more details.
      13             : 
      14             : // You should have received a copy of the GNU Lesser General Public
      15             : // License along with this library; if not, write to the Free Software
      16             : // Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
      17             : 
      18             : 
      19             : 
      20             : #ifndef LIBMESH_OSTREAM_PROXY_H
      21             : #define LIBMESH_OSTREAM_PROXY_H
      22             : 
      23             : 
      24             : 
      25             : // C++ includes
      26             : #include <iostream>
      27             : 
      28             : namespace libMesh
      29             : {
      30             : 
      31             : /**
      32             :  * This class is intended to be reseatable like a pointer-to-ostream
      33             :  * for flexibility, but to look like a reference when used to produce
      34             :  * less awkward user code.
      35             :  *
      36             :  * It is up to the user to ensure that the target ostream remains valid.
      37             :  *
      38             :  * \author Roy Stogner
      39             :  * \date 2010
      40             :  */
      41             : template <typename charT=char, typename traits=std::char_traits<charT>>
      42             : class BasicOStreamProxy
      43             : {
      44             : public:
      45             :   /**
      46             :    * This class is going to be used to proxy for ostream, but other
      47             :    * character and traits types are possible
      48             :    */
      49             :   typedef std::basic_ostream<charT,traits> streamT;
      50             : 
      51             :   /**
      52             :    * This class is going to be used to proxy for ostream, but other
      53             :    * character and traits types are possible
      54             :    */
      55             :   typedef std::basic_streambuf<charT,traits> streambufT;
      56             : 
      57             :   /**
      58             :    * Default constructor.  Takes a reference to the \p target ostream
      59             :    * to which we pass output.  The user is responsible for ensuring
      60             :    * that this target exists for as long as the proxy does.
      61             :    */
      62        1100 :   BasicOStreamProxy (streamT & target) : _target(&target) {}
      63             : 
      64             :   /**
      65             :    * Shallow copy constructor.  Output in the new object is passed to
      66             :    * the same target ostream as in the old object.  The user is
      67             :    * responsible for ensuring that this target exists for as long as
      68             :    * the proxies do.
      69             :    */
      70           0 :   BasicOStreamProxy (BasicOStreamProxy & old) : _target(old._target) {}
      71             : 
      72             :   /**
      73             :    * Reset the internal target to a new \p target output stream.
      74             :    */
      75           0 :   BasicOStreamProxy & operator= (streamT & target)
      76             :   {
      77           0 :     _target = &target;
      78           0 :     return *this;
      79             :   }
      80             : 
      81             :   /**
      82             :    * Reset the target to the same output stream as in \p old
      83             :    */
      84             :   BasicOStreamProxy & operator= (const BasicOStreamProxy & old)
      85             :   {
      86             :     _target = old._target;
      87             :     return *this;
      88             :   }
      89             : 
      90             :   /**
      91             :    * Default destructor.
      92             :    */
      93             :   ~BasicOStreamProxy () = default;
      94             : 
      95             :   //
      96             :   // Functions that get passed to the proxied target:
      97             :   //
      98             : 
      99             :   /**
     100             :    * Conversion to ostream &, for when we get passed to a function
     101             :    * requesting one.
     102             :    */
     103       15791 :   operator streamT & () { return *_target; }
     104             : 
     105             :   /**
     106             :    * Conversion to const ostream &, for when we get passed to a
     107             :    * function requesting one.
     108             :    */
     109             :   operator const streamT &() const { return *_target; }
     110             : 
     111             :   /**
     112             :    * Redirect any output to the target.
     113             :    */
     114             :   template<typename T>
     115       14421 :   BasicOStreamProxy & operator<< (const T & in)
     116             :   {
     117      534327 :     (*_target) << in; return *this;
     118             :   }
     119             : 
     120             :   /**
     121             :    * Redirect any ostream manipulators to the target.
     122             :    */
     123           0 :   BasicOStreamProxy & operator<< (streamT & (*in)(streamT &))
     124             :   {
     125      374789 :     (*_target) << in; return *this;
     126             :   }
     127             : 
     128             :   /**
     129             :    * Redirect any ios manipulators to the target.
     130             :    */
     131             :   BasicOStreamProxy & operator<< (std::basic_ios<charT,traits> & (*in)(std::basic_ios<charT,traits> &))
     132             :   {
     133             :     (*_target) << in; return *this;
     134             :   }
     135             : 
     136             :   /**
     137             :    * Redirect any ios_base manipulators to the target.
     138             :    */
     139        2896 :   BasicOStreamProxy & operator<< (std::ios_base & (*in)(std::ios_base &))
     140             :   {
     141      105241 :     (*_target) << in; return *this;
     142             :   }
     143             : 
     144             :   /**
     145             :    * Get the associated stream buffer
     146             :    */
     147             :   streambufT * rdbuf () const { return _target->rdbuf(); }
     148             : 
     149             :   /**
     150             :    * Set the associated stream buffer
     151             :    */
     152       13620 :   streambufT * rdbuf ( streambufT * sb ) { return _target->rdbuf(sb); }
     153             : 
     154             :   /**
     155             :    * Flush the associated stream buffer
     156             :    */
     157           0 :   BasicOStreamProxy & flush () { _target->flush(); return *this; }
     158             : 
     159             :   /**
     160             :    * Get the associated format flags
     161             :    */
     162             :   std::ios_base::fmtflags flags ( ) const
     163             :   { return _target->flags(); }
     164             : 
     165             :   /**
     166             :    * Set/get the associated format flags
     167             :    */
     168             :   std::ios_base::fmtflags flags ( std::ios_base::fmtflags fmtfl )
     169             :   { return _target->flags(fmtfl); }
     170             : 
     171             :   /**
     172             :    * Set the associated flags
     173             :    */
     174           0 :   std::ios_base::fmtflags setf ( std::ios_base::fmtflags fmtfl )
     175           0 :   { return _target->setf(fmtfl); }
     176             : 
     177             :   /**
     178             :    * Set the associated flags
     179             :    */
     180             :   std::ios_base::fmtflags setf ( std::ios_base::fmtflags fmtfl,
     181             :                                  std::ios_base::fmtflags mask )
     182             :   { return _target->setf(fmtfl, mask); }
     183             : 
     184             :   /**
     185             :    * Clear the associated flags
     186             :    */
     187           0 :   void unsetf ( std::ios_base::fmtflags mask )
     188           0 :   { _target->unsetf(mask); }
     189             : 
     190             :   /**
     191             :    * Get the associated write precision
     192             :    */
     193           0 :   std::streamsize precision () const
     194           0 :   { return _target->precision(); }
     195             : 
     196             :   /**
     197             :    * Set the associated write precision
     198             :    */
     199           0 :   std::streamsize precision ( std::streamsize prec )
     200           0 :   { return _target->precision(prec); }
     201             : 
     202             :   //
     203             :   // Functions that affect the Proxy class:
     204             :   //
     205             : 
     206             :   /**
     207             :    * Reset the proxy to point to a different \p target.
     208             :    *
     209             :    * \note This does not delete the previous target.
     210             :    */
     211           0 :   void reset (streamT & target) { _target = &target; }
     212             : 
     213             :   /**
     214             :    * Rather than implement every ostream/ios/ios_base function, we'll
     215             :    * be lazy and make esoteric uses go through a \p get() function.
     216             :    */
     217           0 :   streamT * get()
     218             :   {
     219           0 :     return _target;
     220             :   }
     221             : 
     222             :   /**
     223             :    * Rather than implement every ostream/ios/ios_base function, we'll
     224             :    * be lazy and make esoteric uses go through a \p get() function.
     225             :    */
     226             :   const streamT * get() const
     227             :   {
     228             :     return _target;
     229             :   }
     230             : 
     231             :   /**
     232             :    * Returns the position of the character in the current stream.
     233             :    */
     234             :   std::streampos tellp() { return _target->tellp(); }
     235             : 
     236             : private:
     237             :   /**
     238             :    * The pointer to the "real" ostream we send everything to.
     239             :    */
     240             :   streamT * _target;
     241             : };
     242             : 
     243             : typedef BasicOStreamProxy<> OStreamProxy;
     244             : 
     245             : } // namespace libMesh
     246             : 
     247             : #endif // LIBMESH_OSTREAM_PROXY_H