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_MESH_INPUT_H
      21             : #define LIBMESH_MESH_INPUT_H
      22             : 
      23             : 
      24             : // Local includes
      25             : #include "libmesh/libmesh_common.h"
      26             : #include "libmesh/mesh_base.h"
      27             : 
      28             : // C++ includes
      29             : #include <cstddef>
      30             : #include <istream>
      31             : #include <string>
      32             : #include <vector>
      33             : 
      34             : namespace libMesh
      35             : {
      36             : 
      37             : 
      38             : 
      39             : /**
      40             :  * This class defines an abstract interface for \p Mesh input.
      41             :  * Specific classes derived from this class actually implement
      42             :  * reading various mesh formats.
      43             :  *
      44             :  * \author Benjamin S. Kirk
      45             :  * \date 2004
      46             :  */
      47             : template <class MT>
      48             : class MeshInput
      49             : {
      50             : protected:
      51             : 
      52             :   /**
      53             :    * Default constructor. Will set the _obj to nullptr, effectively
      54             :    * rendering this object useless.
      55             :    */
      56             :   explicit
      57             :   MeshInput (bool is_parallel_format = false);
      58             : 
      59             :   /**
      60             :    * Constructor.  Takes a writable reference to an object.
      61             :    * This is the constructor required to read an object.
      62             :    */
      63             :   explicit
      64             :   MeshInput (MT &, const bool is_parallel_format = false);
      65             : 
      66             : public:
      67             : 
      68             :   /**
      69             :    * Destructor.
      70             :    */
      71             :   virtual ~MeshInput ();
      72             : 
      73             :   /**
      74             :    * This method implements reading a mesh from a specified file.
      75             :    *
      76             :    * This should typically be called in parallel if
      77             :    * is_parallel_format(), but should be called only on processor 0
      78             :    * (after which a mesh broadcast() is called) otherwise.
      79             :    */
      80             :   virtual void read (const std::string &) = 0;
      81             : 
      82             :   /**
      83             :    * Returns true iff this mesh file format and input class are
      84             :    * parallelized, so that all processors can read their share of the
      85             :    * data at once.
      86             :    */
      87             :   bool is_parallel_format () const { return this->_is_parallel_format; }
      88             : 
      89             : protected:
      90             : 
      91             :   /**
      92             :    * \returns The object as a writable reference.
      93             :    */
      94             :   MT & mesh ();
      95             : 
      96             :   /**
      97             :    * Sets the number of partitions in the mesh.  Typically this gets
      98             :    * done by the partitioner, but some parallel file formats begin
      99             :    * "pre-partitioned".
     100             :    */
     101        4362 :   void set_n_partitions (unsigned int n_parts) { this->mesh().set_n_partitions() = n_parts; }
     102             : 
     103             :   /**
     104             :    * A vector of bools describing what dimension elements
     105             :    * have been encountered when reading a mesh.
     106             :    */
     107             :   std::vector<bool> elems_of_dimension;
     108             : 
     109             :   /**
     110             :    * Reads input from \p in, skipping all the lines
     111             :    * that start with the character \p comment_start.
     112             :    */
     113             :   void skip_comment_lines (std::istream & in,
     114             :                            const char comment_start);
     115             : 
     116             : private:
     117             : 
     118             : 
     119             :   /**
     120             :    * A pointer to a non-const object object.
     121             :    * This allows us to read the object from file.
     122             :    */
     123             :   MT * _obj;
     124             : 
     125             :   /**
     126             :    * Flag specifying whether this format is parallel-capable.
     127             :    * If this is false (default) I/O is only permitted when the mesh
     128             :    * has been serialized.
     129             :    */
     130             :   const bool _is_parallel_format;
     131             : };
     132             : 
     133             : 
     134             : 
     135             : // ------------------------------------------------------------
     136             : // MeshInput inline members
     137             : template <class MT>
     138             : inline
     139        4656 : MeshInput<MT>::MeshInput (const bool is_parallel_format) :
     140             :   elems_of_dimension(),
     141        3352 :   _obj (nullptr),
     142        5308 :   _is_parallel_format(is_parallel_format)
     143             : {
     144         652 : }
     145             : 
     146             : 
     147             : 
     148             : template <class MT>
     149             : inline
     150       83937 : MeshInput<MT>::MeshInput (MT & obj, const bool is_parallel_format) :
     151             :   elems_of_dimension(),
     152       79090 :   _obj (&obj),
     153       83937 :   _is_parallel_format(is_parallel_format)
     154             : {
     155       83937 :   if (!_is_parallel_format && !this->mesh().is_serial())
     156             :     {
     157       47003 :       if (this->mesh().processor_id() == 0)
     158             :         {
     159        5888 :           libmesh_do_once(libMesh::out <<
     160             :                           "Warning:  This MeshOutput subclass only supports meshes which have been serialized!"
     161             :                           << std::endl;);
     162             :         }
     163             :     }
     164       83937 : }
     165             : 
     166             : 
     167             : 
     168             : template <class MT>
     169             : inline
     170        1328 : MeshInput<MT>::~MeshInput ()
     171             : {
     172       51649 : }
     173             : 
     174             : 
     175             : 
     176             : template <class MT>
     177             : inline
     178      225209 : MT & MeshInput<MT>::mesh ()
     179             : {
     180      225209 :   libmesh_error_msg_if(_obj == nullptr, "ERROR: _obj should not be nullptr!");
     181      225209 :   return *_obj;
     182             : }
     183             : 
     184             : 
     185             : 
     186             : template <class MT>
     187          34 : void MeshInput<MT>::skip_comment_lines (std::istream & in,
     188             :                                         const char comment_start)
     189             : {
     190             :   char c, line[256];
     191             : 
     192         100 :   while (in.get(c), c==comment_start)
     193          72 :     in.getline (line, 255);
     194             : 
     195             :   // put back first character of
     196             :   // first non-comment line
     197          28 :   in.putback (c);
     198          28 : }
     199             : 
     200             : 
     201             : } // namespace libMesh
     202             : 
     203             : 
     204             : #endif // LIBMESH_MESH_INPUT_H