COIN-OR::LEMON - Graph Library

source: lemon/lemon/lgf_reader.h @ 631:33c6b6e755cd

Last change on this file since 631:33c6b6e755cd was 631:33c6b6e755cd, checked in by Peter Kovacs <kpeter@…>, 10 years ago

Small doc improvements (#263)

File size: 78.5 KB
Line 
1/* -*- mode: C++; indent-tabs-mode: nil; -*-
2 *
3 * This file is a part of LEMON, a generic C++ optimization library.
4 *
5 * Copyright (C) 2003-2009
6 * Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport
7 * (Egervary Research Group on Combinatorial Optimization, EGRES).
8 *
9 * Permission to use, modify and distribute this software is granted
10 * provided that this copyright notice appears in all copies. For
11 * precise terms see the accompanying LICENSE file.
12 *
13 * This software is provided "AS IS" with no warranty of any kind,
14 * express or implied, and with no claim as to its suitability for any
15 * purpose.
16 *
17 */
18
19///\ingroup lemon_io
20///\file
21///\brief \ref lgf-format "LEMON Graph Format" reader.
22
23
24#ifndef LEMON_LGF_READER_H
25#define LEMON_LGF_READER_H
26
27#include <iostream>
28#include <fstream>
29#include <sstream>
30
31#include <set>
32#include <map>
33
34#include <lemon/core.h>
35
36#include <lemon/lgf_writer.h>
37
38#include <lemon/concept_check.h>
39#include <lemon/concepts/maps.h>
40
41namespace lemon {
42
43  namespace _reader_bits {
44
45    template <typename Value>
46    struct DefaultConverter {
47      Value operator()(const std::string& str) {
48        std::istringstream is(str);
49        Value value;
50        if (!(is >> value)) {
51          throw FormatError("Cannot read token");
52        }
53
54        char c;
55        if (is >> std::ws >> c) {
56          throw FormatError("Remaining characters in token");
57        }
58        return value;
59      }
60    };
61
62    template <>
63    struct DefaultConverter<std::string> {
64      std::string operator()(const std::string& str) {
65        return str;
66      }
67    };
68
69    template <typename _Item>
70    class MapStorageBase {
71    public:
72      typedef _Item Item;
73
74    public:
75      MapStorageBase() {}
76      virtual ~MapStorageBase() {}
77
78      virtual void set(const Item& item, const std::string& value) = 0;
79
80    };
81
82    template <typename _Item, typename _Map,
83              typename _Converter = DefaultConverter<typename _Map::Value> >
84    class MapStorage : public MapStorageBase<_Item> {
85    public:
86      typedef _Map Map;
87      typedef _Converter Converter;
88      typedef _Item Item;
89
90    private:
91      Map& _map;
92      Converter _converter;
93
94    public:
95      MapStorage(Map& map, const Converter& converter = Converter())
96        : _map(map), _converter(converter) {}
97      virtual ~MapStorage() {}
98
99      virtual void set(const Item& item ,const std::string& value) {
100        _map.set(item, _converter(value));
101      }
102    };
103
104    template <typename _Graph, bool _dir, typename _Map,
105              typename _Converter = DefaultConverter<typename _Map::Value> >
106    class GraphArcMapStorage : public MapStorageBase<typename _Graph::Edge> {
107    public:
108      typedef _Map Map;
109      typedef _Converter Converter;
110      typedef _Graph Graph;
111      typedef typename Graph::Edge Item;
112      static const bool dir = _dir;
113
114    private:
115      const Graph& _graph;
116      Map& _map;
117      Converter _converter;
118
119    public:
120      GraphArcMapStorage(const Graph& graph, Map& map,
121                         const Converter& converter = Converter())
122        : _graph(graph), _map(map), _converter(converter) {}
123      virtual ~GraphArcMapStorage() {}
124
125      virtual void set(const Item& item ,const std::string& value) {
126        _map.set(_graph.direct(item, dir), _converter(value));
127      }
128    };
129
130    class ValueStorageBase {
131    public:
132      ValueStorageBase() {}
133      virtual ~ValueStorageBase() {}
134
135      virtual void set(const std::string&) = 0;
136    };
137
138    template <typename _Value, typename _Converter = DefaultConverter<_Value> >
139    class ValueStorage : public ValueStorageBase {
140    public:
141      typedef _Value Value;
142      typedef _Converter Converter;
143
144    private:
145      Value& _value;
146      Converter _converter;
147
148    public:
149      ValueStorage(Value& value, const Converter& converter = Converter())
150        : _value(value), _converter(converter) {}
151
152      virtual void set(const std::string& value) {
153        _value = _converter(value);
154      }
155    };
156
157    template <typename Value>
158    struct MapLookUpConverter {
159      const std::map<std::string, Value>& _map;
160
161      MapLookUpConverter(const std::map<std::string, Value>& map)
162        : _map(map) {}
163
164      Value operator()(const std::string& str) {
165        typename std::map<std::string, Value>::const_iterator it =
166          _map.find(str);
167        if (it == _map.end()) {
168          std::ostringstream msg;
169          msg << "Item not found: " << str;
170          throw FormatError(msg.str());
171        }
172        return it->second;
173      }
174    };
175
176    template <typename Graph>
177    struct GraphArcLookUpConverter {
178      const Graph& _graph;
179      const std::map<std::string, typename Graph::Edge>& _map;
180
181      GraphArcLookUpConverter(const Graph& graph,
182                              const std::map<std::string,
183                                             typename Graph::Edge>& map)
184        : _graph(graph), _map(map) {}
185
186      typename Graph::Arc operator()(const std::string& str) {
187        if (str.empty() || (str[0] != '+' && str[0] != '-')) {
188          throw FormatError("Item must start with '+' or '-'");
189        }
190        typename std::map<std::string, typename Graph::Edge>
191          ::const_iterator it = _map.find(str.substr(1));
192        if (it == _map.end()) {
193          throw FormatError("Item not found");
194        }
195        return _graph.direct(it->second, str[0] == '+');
196      }
197    };
198
199    inline bool isWhiteSpace(char c) {
200      return c == ' ' || c == '\t' || c == '\v' ||
201        c == '\n' || c == '\r' || c == '\f';
202    }
203
204    inline bool isOct(char c) {
205      return '0' <= c && c <='7';
206    }
207
208    inline int valueOct(char c) {
209      LEMON_ASSERT(isOct(c), "The character is not octal.");
210      return c - '0';
211    }
212
213    inline bool isHex(char c) {
214      return ('0' <= c && c <= '9') ||
215        ('a' <= c && c <= 'z') ||
216        ('A' <= c && c <= 'Z');
217    }
218
219    inline int valueHex(char c) {
220      LEMON_ASSERT(isHex(c), "The character is not hexadecimal.");
221      if ('0' <= c && c <= '9') return c - '0';
222      if ('a' <= c && c <= 'z') return c - 'a' + 10;
223      return c - 'A' + 10;
224    }
225
226    inline bool isIdentifierFirstChar(char c) {
227      return ('a' <= c && c <= 'z') ||
228        ('A' <= c && c <= 'Z') || c == '_';
229    }
230
231    inline bool isIdentifierChar(char c) {
232      return isIdentifierFirstChar(c) ||
233        ('0' <= c && c <= '9');
234    }
235
236    inline char readEscape(std::istream& is) {
237      char c;
238      if (!is.get(c))
239        throw FormatError("Escape format error");
240
241      switch (c) {
242      case '\\':
243        return '\\';
244      case '\"':
245        return '\"';
246      case '\'':
247        return '\'';
248      case '\?':
249        return '\?';
250      case 'a':
251        return '\a';
252      case 'b':
253        return '\b';
254      case 'f':
255        return '\f';
256      case 'n':
257        return '\n';
258      case 'r':
259        return '\r';
260      case 't':
261        return '\t';
262      case 'v':
263        return '\v';
264      case 'x':
265        {
266          int code;
267          if (!is.get(c) || !isHex(c))
268            throw FormatError("Escape format error");
269          else if (code = valueHex(c), !is.get(c) || !isHex(c)) is.putback(c);
270          else code = code * 16 + valueHex(c);
271          return code;
272        }
273      default:
274        {
275          int code;
276          if (!isOct(c))
277            throw FormatError("Escape format error");
278          else if (code = valueOct(c), !is.get(c) || !isOct(c))
279            is.putback(c);
280          else if (code = code * 8 + valueOct(c), !is.get(c) || !isOct(c))
281            is.putback(c);
282          else code = code * 8 + valueOct(c);
283          return code;
284        }
285      }
286    }
287
288    inline std::istream& readToken(std::istream& is, std::string& str) {
289      std::ostringstream os;
290
291      char c;
292      is >> std::ws;
293
294      if (!is.get(c))
295        return is;
296
297      if (c == '\"') {
298        while (is.get(c) && c != '\"') {
299          if (c == '\\')
300            c = readEscape(is);
301          os << c;
302        }
303        if (!is)
304          throw FormatError("Quoted format error");
305      } else {
306        is.putback(c);
307        while (is.get(c) && !isWhiteSpace(c)) {
308          if (c == '\\')
309            c = readEscape(is);
310          os << c;
311        }
312        if (!is) {
313          is.clear();
314        } else {
315          is.putback(c);
316        }
317      }
318      str = os.str();
319      return is;
320    }
321
322    class Section {
323    public:
324      virtual ~Section() {}
325      virtual void process(std::istream& is, int& line_num) = 0;
326    };
327
328    template <typename Functor>
329    class LineSection : public Section {
330    private:
331
332      Functor _functor;
333
334    public:
335
336      LineSection(const Functor& functor) : _functor(functor) {}
337      virtual ~LineSection() {}
338
339      virtual void process(std::istream& is, int& line_num) {
340        char c;
341        std::string line;
342        while (is.get(c) && c != '@') {
343          if (c == '\n') {
344            ++line_num;
345          } else if (c == '#') {
346            getline(is, line);
347            ++line_num;
348          } else if (!isWhiteSpace(c)) {
349            is.putback(c);
350            getline(is, line);
351            _functor(line);
352            ++line_num;
353          }
354        }
355        if (is) is.putback(c);
356        else if (is.eof()) is.clear();
357      }
358    };
359
360    template <typename Functor>
361    class StreamSection : public Section {
362    private:
363
364      Functor _functor;
365
366    public:
367
368      StreamSection(const Functor& functor) : _functor(functor) {}
369      virtual ~StreamSection() {}
370
371      virtual void process(std::istream& is, int& line_num) {
372        _functor(is, line_num);
373        char c;
374        std::string line;
375        while (is.get(c) && c != '@') {
376          if (c == '\n') {
377            ++line_num;
378          } else if (!isWhiteSpace(c)) {
379            getline(is, line);
380            ++line_num;
381          }
382        }
383        if (is) is.putback(c);
384        else if (is.eof()) is.clear();
385      }
386    };
387
388  }
389
390  template <typename Digraph>
391  class DigraphReader;
392
393  template <typename Digraph>
394  DigraphReader<Digraph> digraphReader(Digraph& digraph,
395                                       std::istream& is = std::cin);
396  template <typename Digraph>
397  DigraphReader<Digraph> digraphReader(Digraph& digraph, const std::string& fn);
398  template <typename Digraph>
399  DigraphReader<Digraph> digraphReader(Digraph& digraph, const char *fn);
400
401  /// \ingroup lemon_io
402  ///
403  /// \brief \ref lgf-format "LGF" reader for directed graphs
404  ///
405  /// This utility reads an \ref lgf-format "LGF" file.
406  ///
407  /// The reading method does a batch processing. The user creates a
408  /// reader object, then various reading rules can be added to the
409  /// reader, and eventually the reading is executed with the \c run()
410  /// member function. A map reading rule can be added to the reader
411  /// with the \c nodeMap() or \c arcMap() members. An optional
412  /// converter parameter can also be added as a standard functor
413  /// converting from \c std::string to the value type of the map. If it
414  /// is set, it will determine how the tokens in the file should be
415  /// converted to the value type of the map. If the functor is not set,
416  /// then a default conversion will be used. One map can be read into
417  /// multiple map objects at the same time. The \c attribute(), \c
418  /// node() and \c arc() functions are used to add attribute reading
419  /// rules.
420  ///
421  ///\code
422  /// DigraphReader<Digraph>(digraph, std::cin).
423  ///   nodeMap("coordinates", coord_map).
424  ///   arcMap("capacity", cap_map).
425  ///   node("source", src).
426  ///   node("target", trg).
427  ///   attribute("caption", caption).
428  ///   run();
429  ///\endcode
430  ///
431  /// By default the reader uses the first section in the file of the
432  /// proper type. If a section has an optional name, then it can be
433  /// selected for reading by giving an optional name parameter to the
434  /// \c nodes(), \c arcs() or \c attributes() functions.
435  ///
436  /// The \c useNodes() and \c useArcs() functions are used to tell the reader
437  /// that the nodes or arcs should not be constructed (added to the
438  /// graph) during the reading, but instead the label map of the items
439  /// are given as a parameter of these functions. An
440  /// application of these functions is multipass reading, which is
441  /// important if two \c \@arcs sections must be read from the
442  /// file. In this case the first phase would read the node set and one
443  /// of the arc sets, while the second phase would read the second arc
444  /// set into an \e ArcSet class (\c SmartArcSet or \c ListArcSet).
445  /// The previously read label node map should be passed to the \c
446  /// useNodes() functions. Another application of multipass reading when
447  /// paths are given as a node map or an arc map.
448  /// It is impossible to read this in
449  /// a single pass, because the arcs are not constructed when the node
450  /// maps are read.
451  template <typename GR>
452  class DigraphReader {
453  public:
454
455    typedef GR Digraph;
456
457  private:
458
459    TEMPLATE_DIGRAPH_TYPEDEFS(Digraph);
460
461    std::istream* _is;
462    bool local_is;
463    std::string _filename;
464
465    Digraph& _digraph;
466
467    std::string _nodes_caption;
468    std::string _arcs_caption;
469    std::string _attributes_caption;
470
471    typedef std::map<std::string, Node> NodeIndex;
472    NodeIndex _node_index;
473    typedef std::map<std::string, Arc> ArcIndex;
474    ArcIndex _arc_index;
475
476    typedef std::vector<std::pair<std::string,
477      _reader_bits::MapStorageBase<Node>*> > NodeMaps;
478    NodeMaps _node_maps;
479
480    typedef std::vector<std::pair<std::string,
481      _reader_bits::MapStorageBase<Arc>*> >ArcMaps;
482    ArcMaps _arc_maps;
483
484    typedef std::multimap<std::string, _reader_bits::ValueStorageBase*>
485      Attributes;
486    Attributes _attributes;
487
488    bool _use_nodes;
489    bool _use_arcs;
490
491    bool _skip_nodes;
492    bool _skip_arcs;
493
494    int line_num;
495    std::istringstream line;
496
497  public:
498
499    /// \brief Constructor
500    ///
501    /// Construct a directed graph reader, which reads from the given
502    /// input stream.
503    DigraphReader(Digraph& digraph, std::istream& is = std::cin)
504      : _is(&is), local_is(false), _digraph(digraph),
505        _use_nodes(false), _use_arcs(false),
506        _skip_nodes(false), _skip_arcs(false) {}
507
508    /// \brief Constructor
509    ///
510    /// Construct a directed graph reader, which reads from the given
511    /// file.
512    DigraphReader(Digraph& digraph, const std::string& fn)
513      : _is(new std::ifstream(fn.c_str())), local_is(true),
514        _filename(fn), _digraph(digraph),
515        _use_nodes(false), _use_arcs(false),
516        _skip_nodes(false), _skip_arcs(false) {
517      if (!(*_is)) {
518        delete _is;
519        throw IoError("Cannot open file", fn);
520      }
521    }
522
523    /// \brief Constructor
524    ///
525    /// Construct a directed graph reader, which reads from the given
526    /// file.
527    DigraphReader(Digraph& digraph, const char* fn)
528      : _is(new std::ifstream(fn)), local_is(true),
529        _filename(fn), _digraph(digraph),
530        _use_nodes(false), _use_arcs(false),
531        _skip_nodes(false), _skip_arcs(false) {
532      if (!(*_is)) {
533        delete _is;
534        throw IoError("Cannot open file", fn);
535      }
536    }
537
538    /// \brief Destructor
539    ~DigraphReader() {
540      for (typename NodeMaps::iterator it = _node_maps.begin();
541           it != _node_maps.end(); ++it) {
542        delete it->second;
543      }
544
545      for (typename ArcMaps::iterator it = _arc_maps.begin();
546           it != _arc_maps.end(); ++it) {
547        delete it->second;
548      }
549
550      for (typename Attributes::iterator it = _attributes.begin();
551           it != _attributes.end(); ++it) {
552        delete it->second;
553      }
554
555      if (local_is) {
556        delete _is;
557      }
558
559    }
560
561  private:
562
563    template <typename DGR>
564    friend DigraphReader<DGR> digraphReader(DGR& digraph, std::istream& is);
565    template <typename DGR>
566    friend DigraphReader<DGR> digraphReader(DGR& digraph,
567                                            const std::string& fn);
568    template <typename DGR>
569    friend DigraphReader<DGR> digraphReader(DGR& digraph, const char *fn);
570
571    DigraphReader(DigraphReader& other)
572      : _is(other._is), local_is(other.local_is), _digraph(other._digraph),
573        _use_nodes(other._use_nodes), _use_arcs(other._use_arcs),
574        _skip_nodes(other._skip_nodes), _skip_arcs(other._skip_arcs) {
575
576      other._is = 0;
577      other.local_is = false;
578
579      _node_index.swap(other._node_index);
580      _arc_index.swap(other._arc_index);
581
582      _node_maps.swap(other._node_maps);
583      _arc_maps.swap(other._arc_maps);
584      _attributes.swap(other._attributes);
585
586      _nodes_caption = other._nodes_caption;
587      _arcs_caption = other._arcs_caption;
588      _attributes_caption = other._attributes_caption;
589
590    }
591
592    DigraphReader& operator=(const DigraphReader&);
593
594  public:
595
596    /// \name Reading Rules
597    /// @{
598
599    /// \brief Node map reading rule
600    ///
601    /// Add a node map reading rule to the reader.
602    template <typename Map>
603    DigraphReader& nodeMap(const std::string& caption, Map& map) {
604      checkConcept<concepts::WriteMap<Node, typename Map::Value>, Map>();
605      _reader_bits::MapStorageBase<Node>* storage =
606        new _reader_bits::MapStorage<Node, Map>(map);
607      _node_maps.push_back(std::make_pair(caption, storage));
608      return *this;
609    }
610
611    /// \brief Node map reading rule
612    ///
613    /// Add a node map reading rule with specialized converter to the
614    /// reader.
615    template <typename Map, typename Converter>
616    DigraphReader& nodeMap(const std::string& caption, Map& map,
617                           const Converter& converter = Converter()) {
618      checkConcept<concepts::WriteMap<Node, typename Map::Value>, Map>();
619      _reader_bits::MapStorageBase<Node>* storage =
620        new _reader_bits::MapStorage<Node, Map, Converter>(map, converter);
621      _node_maps.push_back(std::make_pair(caption, storage));
622      return *this;
623    }
624
625    /// \brief Arc map reading rule
626    ///
627    /// Add an arc map reading rule to the reader.
628    template <typename Map>
629    DigraphReader& arcMap(const std::string& caption, Map& map) {
630      checkConcept<concepts::WriteMap<Arc, typename Map::Value>, Map>();
631      _reader_bits::MapStorageBase<Arc>* storage =
632        new _reader_bits::MapStorage<Arc, Map>(map);
633      _arc_maps.push_back(std::make_pair(caption, storage));
634      return *this;
635    }
636
637    /// \brief Arc map reading rule
638    ///
639    /// Add an arc map reading rule with specialized converter to the
640    /// reader.
641    template <typename Map, typename Converter>
642    DigraphReader& arcMap(const std::string& caption, Map& map,
643                          const Converter& converter = Converter()) {
644      checkConcept<concepts::WriteMap<Arc, typename Map::Value>, Map>();
645      _reader_bits::MapStorageBase<Arc>* storage =
646        new _reader_bits::MapStorage<Arc, Map, Converter>(map, converter);
647      _arc_maps.push_back(std::make_pair(caption, storage));
648      return *this;
649    }
650
651    /// \brief Attribute reading rule
652    ///
653    /// Add an attribute reading rule to the reader.
654    template <typename Value>
655    DigraphReader& attribute(const std::string& caption, Value& value) {
656      _reader_bits::ValueStorageBase* storage =
657        new _reader_bits::ValueStorage<Value>(value);
658      _attributes.insert(std::make_pair(caption, storage));
659      return *this;
660    }
661
662    /// \brief Attribute reading rule
663    ///
664    /// Add an attribute reading rule with specialized converter to the
665    /// reader.
666    template <typename Value, typename Converter>
667    DigraphReader& attribute(const std::string& caption, Value& value,
668                             const Converter& converter = Converter()) {
669      _reader_bits::ValueStorageBase* storage =
670        new _reader_bits::ValueStorage<Value, Converter>(value, converter);
671      _attributes.insert(std::make_pair(caption, storage));
672      return *this;
673    }
674
675    /// \brief Node reading rule
676    ///
677    /// Add a node reading rule to reader.
678    DigraphReader& node(const std::string& caption, Node& node) {
679      typedef _reader_bits::MapLookUpConverter<Node> Converter;
680      Converter converter(_node_index);
681      _reader_bits::ValueStorageBase* storage =
682        new _reader_bits::ValueStorage<Node, Converter>(node, converter);
683      _attributes.insert(std::make_pair(caption, storage));
684      return *this;
685    }
686
687    /// \brief Arc reading rule
688    ///
689    /// Add an arc reading rule to reader.
690    DigraphReader& arc(const std::string& caption, Arc& arc) {
691      typedef _reader_bits::MapLookUpConverter<Arc> Converter;
692      Converter converter(_arc_index);
693      _reader_bits::ValueStorageBase* storage =
694        new _reader_bits::ValueStorage<Arc, Converter>(arc, converter);
695      _attributes.insert(std::make_pair(caption, storage));
696      return *this;
697    }
698
699    /// @}
700
701    /// \name Select Section by Name
702    /// @{
703
704    /// \brief Set \c \@nodes section to be read
705    ///
706    /// Set \c \@nodes section to be read
707    DigraphReader& nodes(const std::string& caption) {
708      _nodes_caption = caption;
709      return *this;
710    }
711
712    /// \brief Set \c \@arcs section to be read
713    ///
714    /// Set \c \@arcs section to be read
715    DigraphReader& arcs(const std::string& caption) {
716      _arcs_caption = caption;
717      return *this;
718    }
719
720    /// \brief Set \c \@attributes section to be read
721    ///
722    /// Set \c \@attributes section to be read
723    DigraphReader& attributes(const std::string& caption) {
724      _attributes_caption = caption;
725      return *this;
726    }
727
728    /// @}
729
730    /// \name Using Previously Constructed Node or Arc Set
731    /// @{
732
733    /// \brief Use previously constructed node set
734    ///
735    /// Use previously constructed node set, and specify the node
736    /// label map.
737    template <typename Map>
738    DigraphReader& useNodes(const Map& map) {
739      checkConcept<concepts::ReadMap<Node, typename Map::Value>, Map>();
740      LEMON_ASSERT(!_use_nodes, "Multiple usage of useNodes() member");
741      _use_nodes = true;
742      _writer_bits::DefaultConverter<typename Map::Value> converter;
743      for (NodeIt n(_digraph); n != INVALID; ++n) {
744        _node_index.insert(std::make_pair(converter(map[n]), n));
745      }
746      return *this;
747    }
748
749    /// \brief Use previously constructed node set
750    ///
751    /// Use previously constructed node set, and specify the node
752    /// label map and a functor which converts the label map values to
753    /// \c std::string.
754    template <typename Map, typename Converter>
755    DigraphReader& useNodes(const Map& map,
756                            const Converter& converter = Converter()) {
757      checkConcept<concepts::ReadMap<Node, typename Map::Value>, Map>();
758      LEMON_ASSERT(!_use_nodes, "Multiple usage of useNodes() member");
759      _use_nodes = true;
760      for (NodeIt n(_digraph); n != INVALID; ++n) {
761        _node_index.insert(std::make_pair(converter(map[n]), n));
762      }
763      return *this;
764    }
765
766    /// \brief Use previously constructed arc set
767    ///
768    /// Use previously constructed arc set, and specify the arc
769    /// label map.
770    template <typename Map>
771    DigraphReader& useArcs(const Map& map) {
772      checkConcept<concepts::ReadMap<Arc, typename Map::Value>, Map>();
773      LEMON_ASSERT(!_use_arcs, "Multiple usage of useArcs() member");
774      _use_arcs = true;
775      _writer_bits::DefaultConverter<typename Map::Value> converter;
776      for (ArcIt a(_digraph); a != INVALID; ++a) {
777        _arc_index.insert(std::make_pair(converter(map[a]), a));
778      }
779      return *this;
780    }
781
782    /// \brief Use previously constructed arc set
783    ///
784    /// Use previously constructed arc set, and specify the arc
785    /// label map and a functor which converts the label map values to
786    /// \c std::string.
787    template <typename Map, typename Converter>
788    DigraphReader& useArcs(const Map& map,
789                           const Converter& converter = Converter()) {
790      checkConcept<concepts::ReadMap<Arc, typename Map::Value>, Map>();
791      LEMON_ASSERT(!_use_arcs, "Multiple usage of useArcs() member");
792      _use_arcs = true;
793      for (ArcIt a(_digraph); a != INVALID; ++a) {
794        _arc_index.insert(std::make_pair(converter(map[a]), a));
795      }
796      return *this;
797    }
798
799    /// \brief Skips the reading of node section
800    ///
801    /// Omit the reading of the node section. This implies that each node
802    /// map reading rule will be abandoned, and the nodes of the graph
803    /// will not be constructed, which usually cause that the arc set
804    /// could not be read due to lack of node name resolving.
805    /// Therefore \c skipArcs() function should also be used, or
806    /// \c useNodes() should be used to specify the label of the nodes.
807    DigraphReader& skipNodes() {
808      LEMON_ASSERT(!_skip_nodes, "Skip nodes already set");
809      _skip_nodes = true;
810      return *this;
811    }
812
813    /// \brief Skips the reading of arc section
814    ///
815    /// Omit the reading of the arc section. This implies that each arc
816    /// map reading rule will be abandoned, and the arcs of the graph
817    /// will not be constructed.
818    DigraphReader& skipArcs() {
819      LEMON_ASSERT(!_skip_arcs, "Skip arcs already set");
820      _skip_arcs = true;
821      return *this;
822    }
823
824    /// @}
825
826  private:
827
828    bool readLine() {
829      std::string str;
830      while(++line_num, std::getline(*_is, str)) {
831        line.clear(); line.str(str);
832        char c;
833        if (line >> std::ws >> c && c != '#') {
834          line.putback(c);
835          return true;
836        }
837      }
838      return false;
839    }
840
841    bool readSuccess() {
842      return static_cast<bool>(*_is);
843    }
844
845    void skipSection() {
846      char c;
847      while (readSuccess() && line >> c && c != '@') {
848        readLine();
849      }
850      if (readSuccess()) {
851        line.putback(c);
852      }
853    }
854
855    void readNodes() {
856
857      std::vector<int> map_index(_node_maps.size());
858      int map_num, label_index;
859
860      char c;
861      if (!readLine() || !(line >> c) || c == '@') {
862        if (readSuccess() && line) line.putback(c);
863        if (!_node_maps.empty())
864          throw FormatError("Cannot find map names");
865        return;
866      }
867      line.putback(c);
868
869      {
870        std::map<std::string, int> maps;
871
872        std::string map;
873        int index = 0;
874        while (_reader_bits::readToken(line, map)) {
875          if (maps.find(map) != maps.end()) {
876            std::ostringstream msg;
877            msg << "Multiple occurence of node map: " << map;
878            throw FormatError(msg.str());
879          }
880          maps.insert(std::make_pair(map, index));
881          ++index;
882        }
883
884        for (int i = 0; i < static_cast<int>(_node_maps.size()); ++i) {
885          std::map<std::string, int>::iterator jt =
886            maps.find(_node_maps[i].first);
887          if (jt == maps.end()) {
888            std::ostringstream msg;
889            msg << "Map not found: " << _node_maps[i].first;
890            throw FormatError(msg.str());
891          }
892          map_index[i] = jt->second;
893        }
894
895        {
896          std::map<std::string, int>::iterator jt = maps.find("label");
897          if (jt != maps.end()) {
898            label_index = jt->second;
899          } else {
900            label_index = -1;
901          }
902        }
903        map_num = maps.size();
904      }
905
906      while (readLine() && line >> c && c != '@') {
907        line.putback(c);
908
909        std::vector<std::string> tokens(map_num);
910        for (int i = 0; i < map_num; ++i) {
911          if (!_reader_bits::readToken(line, tokens[i])) {
912            std::ostringstream msg;
913            msg << "Column not found (" << i + 1 << ")";
914            throw FormatError(msg.str());
915          }
916        }
917        if (line >> std::ws >> c)
918          throw FormatError("Extra character at the end of line");
919
920        Node n;
921        if (!_use_nodes) {
922          n = _digraph.addNode();
923          if (label_index != -1)
924            _node_index.insert(std::make_pair(tokens[label_index], n));
925        } else {
926          if (label_index == -1)
927            throw FormatError("Label map not found");
928          typename std::map<std::string, Node>::iterator it =
929            _node_index.find(tokens[label_index]);
930          if (it == _node_index.end()) {
931            std::ostringstream msg;
932            msg << "Node with label not found: " << tokens[label_index];
933            throw FormatError(msg.str());
934          }
935          n = it->second;
936        }
937
938        for (int i = 0; i < static_cast<int>(_node_maps.size()); ++i) {
939          _node_maps[i].second->set(n, tokens[map_index[i]]);
940        }
941
942      }
943      if (readSuccess()) {
944        line.putback(c);
945      }
946    }
947
948    void readArcs() {
949
950      std::vector<int> map_index(_arc_maps.size());
951      int map_num, label_index;
952
953      char c;
954      if (!readLine() || !(line >> c) || c == '@') {
955        if (readSuccess() && line) line.putback(c);
956        if (!_arc_maps.empty())
957          throw FormatError("Cannot find map names");
958        return;
959      }
960      line.putback(c);
961
962      {
963        std::map<std::string, int> maps;
964
965        std::string map;
966        int index = 0;
967        while (_reader_bits::readToken(line, map)) {
968          if (maps.find(map) != maps.end()) {
969            std::ostringstream msg;
970            msg << "Multiple occurence of arc map: " << map;
971            throw FormatError(msg.str());
972          }
973          maps.insert(std::make_pair(map, index));
974          ++index;
975        }
976
977        for (int i = 0; i < static_cast<int>(_arc_maps.size()); ++i) {
978          std::map<std::string, int>::iterator jt =
979            maps.find(_arc_maps[i].first);
980          if (jt == maps.end()) {
981            std::ostringstream msg;
982            msg << "Map not found: " << _arc_maps[i].first;
983            throw FormatError(msg.str());
984          }
985          map_index[i] = jt->second;
986        }
987
988        {
989          std::map<std::string, int>::iterator jt = maps.find("label");
990          if (jt != maps.end()) {
991            label_index = jt->second;
992          } else {
993            label_index = -1;
994          }
995        }
996        map_num = maps.size();
997      }
998
999      while (readLine() && line >> c && c != '@') {
1000        line.putback(c);
1001
1002        std::string source_token;
1003        std::string target_token;
1004
1005        if (!_reader_bits::readToken(line, source_token))
1006          throw FormatError("Source not found");
1007
1008        if (!_reader_bits::readToken(line, target_token))
1009          throw FormatError("Target not found");
1010
1011        std::vector<std::string> tokens(map_num);
1012        for (int i = 0; i < map_num; ++i) {
1013          if (!_reader_bits::readToken(line, tokens[i])) {
1014            std::ostringstream msg;
1015            msg << "Column not found (" << i + 1 << ")";
1016            throw FormatError(msg.str());
1017          }
1018        }
1019        if (line >> std::ws >> c)
1020          throw FormatError("Extra character at the end of line");
1021
1022        Arc a;
1023        if (!_use_arcs) {
1024
1025          typename NodeIndex::iterator it;
1026
1027          it = _node_index.find(source_token);
1028          if (it == _node_index.end()) {
1029            std::ostringstream msg;
1030            msg << "Item not found: " << source_token;
1031            throw FormatError(msg.str());
1032          }
1033          Node source = it->second;
1034
1035          it = _node_index.find(target_token);
1036          if (it == _node_index.end()) {
1037            std::ostringstream msg;
1038            msg << "Item not found: " << target_token;
1039            throw FormatError(msg.str());
1040          }
1041          Node target = it->second;
1042
1043          a = _digraph.addArc(source, target);
1044          if (label_index != -1)
1045            _arc_index.insert(std::make_pair(tokens[label_index], a));
1046        } else {
1047          if (label_index == -1)
1048            throw FormatError("Label map not found");
1049          typename std::map<std::string, Arc>::iterator it =
1050            _arc_index.find(tokens[label_index]);
1051          if (it == _arc_index.end()) {
1052            std::ostringstream msg;
1053            msg << "Arc with label not found: " << tokens[label_index];
1054            throw FormatError(msg.str());
1055          }
1056          a = it->second;
1057        }
1058
1059        for (int i = 0; i < static_cast<int>(_arc_maps.size()); ++i) {
1060          _arc_maps[i].second->set(a, tokens[map_index[i]]);
1061        }
1062
1063      }
1064      if (readSuccess()) {
1065        line.putback(c);
1066      }
1067    }
1068
1069    void readAttributes() {
1070
1071      std::set<std::string> read_attr;
1072
1073      char c;
1074      while (readLine() && line >> c && c != '@') {
1075        line.putback(c);
1076
1077        std::string attr, token;
1078        if (!_reader_bits::readToken(line, attr))
1079          throw FormatError("Attribute name not found");
1080        if (!_reader_bits::readToken(line, token))
1081          throw FormatError("Attribute value not found");
1082        if (line >> c)
1083          throw FormatError("Extra character at the end of line");
1084
1085        {
1086          std::set<std::string>::iterator it = read_attr.find(attr);
1087          if (it != read_attr.end()) {
1088            std::ostringstream msg;
1089            msg << "Multiple occurence of attribute: " << attr;
1090            throw FormatError(msg.str());
1091          }
1092          read_attr.insert(attr);
1093        }
1094
1095        {
1096          typename Attributes::iterator it = _attributes.lower_bound(attr);
1097          while (it != _attributes.end() && it->first == attr) {
1098            it->second->set(token);
1099            ++it;
1100          }
1101        }
1102
1103      }
1104      if (readSuccess()) {
1105        line.putback(c);
1106      }
1107      for (typename Attributes::iterator it = _attributes.begin();
1108           it != _attributes.end(); ++it) {
1109        if (read_attr.find(it->first) == read_attr.end()) {
1110          std::ostringstream msg;
1111          msg << "Attribute not found: " << it->first;
1112          throw FormatError(msg.str());
1113        }
1114      }
1115    }
1116
1117  public:
1118
1119    /// \name Execution of the Reader
1120    /// @{
1121
1122    /// \brief Start the batch processing
1123    ///
1124    /// This function starts the batch processing
1125    void run() {
1126      LEMON_ASSERT(_is != 0, "This reader assigned to an other reader");
1127
1128      bool nodes_done = _skip_nodes;
1129      bool arcs_done = _skip_arcs;
1130      bool attributes_done = false;
1131
1132      line_num = 0;
1133      readLine();
1134      skipSection();
1135
1136      while (readSuccess()) {
1137        try {
1138          char c;
1139          std::string section, caption;
1140          line >> c;
1141          _reader_bits::readToken(line, section);
1142          _reader_bits::readToken(line, caption);
1143
1144          if (line >> c)
1145            throw FormatError("Extra character at the end of line");
1146
1147          if (section == "nodes" && !nodes_done) {
1148            if (_nodes_caption.empty() || _nodes_caption == caption) {
1149              readNodes();
1150              nodes_done = true;
1151            }
1152          } else if ((section == "arcs" || section == "edges") &&
1153                     !arcs_done) {
1154            if (_arcs_caption.empty() || _arcs_caption == caption) {
1155              readArcs();
1156              arcs_done = true;
1157            }
1158          } else if (section == "attributes" && !attributes_done) {
1159            if (_attributes_caption.empty() || _attributes_caption == caption) {
1160              readAttributes();
1161              attributes_done = true;
1162            }
1163          } else {
1164            readLine();
1165            skipSection();
1166          }
1167        } catch (FormatError& error) {
1168          error.line(line_num);
1169          error.file(_filename);
1170          throw;
1171        }
1172      }
1173
1174      if (!nodes_done) {
1175        throw FormatError("Section @nodes not found");
1176      }
1177
1178      if (!arcs_done) {
1179        throw FormatError("Section @arcs not found");
1180      }
1181
1182      if (!attributes_done && !_attributes.empty()) {
1183        throw FormatError("Section @attributes not found");
1184      }
1185
1186    }
1187
1188    /// @}
1189
1190  };
1191
1192  /// \brief Return a \ref DigraphReader class
1193  ///
1194  /// This function just returns a \ref DigraphReader class.
1195  /// \relates DigraphReader
1196  template <typename Digraph>
1197  DigraphReader<Digraph> digraphReader(Digraph& digraph, std::istream& is) {
1198    DigraphReader<Digraph> tmp(digraph, is);
1199    return tmp;
1200  }
1201
1202  /// \brief Return a \ref DigraphReader class
1203  ///
1204  /// This function just returns a \ref DigraphReader class.
1205  /// \relates DigraphReader
1206  template <typename Digraph>
1207  DigraphReader<Digraph> digraphReader(Digraph& digraph,
1208                                       const std::string& fn) {
1209    DigraphReader<Digraph> tmp(digraph, fn);
1210    return tmp;
1211  }
1212
1213  /// \brief Return a \ref DigraphReader class
1214  ///
1215  /// This function just returns a \ref DigraphReader class.
1216  /// \relates DigraphReader
1217  template <typename Digraph>
1218  DigraphReader<Digraph> digraphReader(Digraph& digraph, const char* fn) {
1219    DigraphReader<Digraph> tmp(digraph, fn);
1220    return tmp;
1221  }
1222
1223  template <typename Graph>
1224  class GraphReader;
1225 
1226  template <typename Graph>
1227  GraphReader<Graph> graphReader(Graph& graph,
1228                                 std::istream& is = std::cin);
1229  template <typename Graph>
1230  GraphReader<Graph> graphReader(Graph& graph, const std::string& fn);
1231  template <typename Graph>
1232  GraphReader<Graph> graphReader(Graph& graph, const char *fn);
1233
1234  /// \ingroup lemon_io
1235  ///
1236  /// \brief \ref lgf-format "LGF" reader for undirected graphs
1237  ///
1238  /// This utility reads an \ref lgf-format "LGF" file.
1239  ///
1240  /// It can be used almost the same way as \c DigraphReader.
1241  /// The only difference is that this class can handle edges and
1242  /// edge maps as well as arcs and arc maps.
1243  ///
1244  /// The columns in the \c \@edges (or \c \@arcs) section are the
1245  /// edge maps. However, if there are two maps with the same name
1246  /// prefixed with \c '+' and \c '-', then these can be read into an
1247  /// arc map.  Similarly, an attribute can be read into an arc, if
1248  /// it's value is an edge label prefixed with \c '+' or \c '-'.
1249  template <typename GR>
1250  class GraphReader {
1251  public:
1252
1253    typedef GR Graph;
1254
1255  private:
1256
1257    TEMPLATE_GRAPH_TYPEDEFS(Graph);
1258
1259    std::istream* _is;
1260    bool local_is;
1261    std::string _filename;
1262
1263    Graph& _graph;
1264
1265    std::string _nodes_caption;
1266    std::string _edges_caption;
1267    std::string _attributes_caption;
1268
1269    typedef std::map<std::string, Node> NodeIndex;
1270    NodeIndex _node_index;
1271    typedef std::map<std::string, Edge> EdgeIndex;
1272    EdgeIndex _edge_index;
1273
1274    typedef std::vector<std::pair<std::string,
1275      _reader_bits::MapStorageBase<Node>*> > NodeMaps;
1276    NodeMaps _node_maps;
1277
1278    typedef std::vector<std::pair<std::string,
1279      _reader_bits::MapStorageBase<Edge>*> > EdgeMaps;
1280    EdgeMaps _edge_maps;
1281
1282    typedef std::multimap<std::string, _reader_bits::ValueStorageBase*>
1283      Attributes;
1284    Attributes _attributes;
1285
1286    bool _use_nodes;
1287    bool _use_edges;
1288
1289    bool _skip_nodes;
1290    bool _skip_edges;
1291
1292    int line_num;
1293    std::istringstream line;
1294
1295  public:
1296
1297    /// \brief Constructor
1298    ///
1299    /// Construct an undirected graph reader, which reads from the given
1300    /// input stream.
1301    GraphReader(Graph& graph, std::istream& is = std::cin)
1302      : _is(&is), local_is(false), _graph(graph),
1303        _use_nodes(false), _use_edges(false),
1304        _skip_nodes(false), _skip_edges(false) {}
1305
1306    /// \brief Constructor
1307    ///
1308    /// Construct an undirected graph reader, which reads from the given
1309    /// file.
1310    GraphReader(Graph& graph, const std::string& fn)
1311      : _is(new std::ifstream(fn.c_str())), local_is(true),
1312        _filename(fn), _graph(graph),
1313        _use_nodes(false), _use_edges(false),
1314        _skip_nodes(false), _skip_edges(false) {
1315      if (!(*_is)) {
1316        delete _is;
1317        throw IoError("Cannot open file", fn);
1318      }
1319    }
1320
1321    /// \brief Constructor
1322    ///
1323    /// Construct an undirected graph reader, which reads from the given
1324    /// file.
1325    GraphReader(Graph& graph, const char* fn)
1326      : _is(new std::ifstream(fn)), local_is(true),
1327        _filename(fn), _graph(graph),
1328        _use_nodes(false), _use_edges(false),
1329        _skip_nodes(false), _skip_edges(false) {
1330      if (!(*_is)) {
1331        delete _is;
1332        throw IoError("Cannot open file", fn);
1333      }
1334    }
1335
1336    /// \brief Destructor
1337    ~GraphReader() {
1338      for (typename NodeMaps::iterator it = _node_maps.begin();
1339           it != _node_maps.end(); ++it) {
1340        delete it->second;
1341      }
1342
1343      for (typename EdgeMaps::iterator it = _edge_maps.begin();
1344           it != _edge_maps.end(); ++it) {
1345        delete it->second;
1346      }
1347
1348      for (typename Attributes::iterator it = _attributes.begin();
1349           it != _attributes.end(); ++it) {
1350        delete it->second;
1351      }
1352
1353      if (local_is) {
1354        delete _is;
1355      }
1356
1357    }
1358
1359  private:
1360    template <typename Graph>
1361    friend GraphReader<Graph> graphReader(Graph& graph, std::istream& is);
1362    template <typename Graph>
1363    friend GraphReader<Graph> graphReader(Graph& graph, const std::string& fn);
1364    template <typename Graph>
1365    friend GraphReader<Graph> graphReader(Graph& graph, const char *fn);
1366
1367    GraphReader(GraphReader& other)
1368      : _is(other._is), local_is(other.local_is), _graph(other._graph),
1369        _use_nodes(other._use_nodes), _use_edges(other._use_edges),
1370        _skip_nodes(other._skip_nodes), _skip_edges(other._skip_edges) {
1371
1372      other._is = 0;
1373      other.local_is = false;
1374
1375      _node_index.swap(other._node_index);
1376      _edge_index.swap(other._edge_index);
1377
1378      _node_maps.swap(other._node_maps);
1379      _edge_maps.swap(other._edge_maps);
1380      _attributes.swap(other._attributes);
1381
1382      _nodes_caption = other._nodes_caption;
1383      _edges_caption = other._edges_caption;
1384      _attributes_caption = other._attributes_caption;
1385
1386    }
1387
1388    GraphReader& operator=(const GraphReader&);
1389
1390  public:
1391
1392    /// \name Reading Rules
1393    /// @{
1394
1395    /// \brief Node map reading rule
1396    ///
1397    /// Add a node map reading rule to the reader.
1398    template <typename Map>
1399    GraphReader& nodeMap(const std::string& caption, Map& map) {
1400      checkConcept<concepts::WriteMap<Node, typename Map::Value>, Map>();
1401      _reader_bits::MapStorageBase<Node>* storage =
1402        new _reader_bits::MapStorage<Node, Map>(map);
1403      _node_maps.push_back(std::make_pair(caption, storage));
1404      return *this;
1405    }
1406
1407    /// \brief Node map reading rule
1408    ///
1409    /// Add a node map reading rule with specialized converter to the
1410    /// reader.
1411    template <typename Map, typename Converter>
1412    GraphReader& nodeMap(const std::string& caption, Map& map,
1413                           const Converter& converter = Converter()) {
1414      checkConcept<concepts::WriteMap<Node, typename Map::Value>, Map>();
1415      _reader_bits::MapStorageBase<Node>* storage =
1416        new _reader_bits::MapStorage<Node, Map, Converter>(map, converter);
1417      _node_maps.push_back(std::make_pair(caption, storage));
1418      return *this;
1419    }
1420
1421    /// \brief Edge map reading rule
1422    ///
1423    /// Add an edge map reading rule to the reader.
1424    template <typename Map>
1425    GraphReader& edgeMap(const std::string& caption, Map& map) {
1426      checkConcept<concepts::WriteMap<Edge, typename Map::Value>, Map>();
1427      _reader_bits::MapStorageBase<Edge>* storage =
1428        new _reader_bits::MapStorage<Edge, Map>(map);
1429      _edge_maps.push_back(std::make_pair(caption, storage));
1430      return *this;
1431    }
1432
1433    /// \brief Edge map reading rule
1434    ///
1435    /// Add an edge map reading rule with specialized converter to the
1436    /// reader.
1437    template <typename Map, typename Converter>
1438    GraphReader& edgeMap(const std::string& caption, Map& map,
1439                          const Converter& converter = Converter()) {
1440      checkConcept<concepts::WriteMap<Edge, typename Map::Value>, Map>();
1441      _reader_bits::MapStorageBase<Edge>* storage =
1442        new _reader_bits::MapStorage<Edge, Map, Converter>(map, converter);
1443      _edge_maps.push_back(std::make_pair(caption, storage));
1444      return *this;
1445    }
1446
1447    /// \brief Arc map reading rule
1448    ///
1449    /// Add an arc map reading rule to the reader.
1450    template <typename Map>
1451    GraphReader& arcMap(const std::string& caption, Map& map) {
1452      checkConcept<concepts::WriteMap<Arc, typename Map::Value>, Map>();
1453      _reader_bits::MapStorageBase<Edge>* forward_storage =
1454        new _reader_bits::GraphArcMapStorage<Graph, true, Map>(_graph, map);
1455      _edge_maps.push_back(std::make_pair('+' + caption, forward_storage));
1456      _reader_bits::MapStorageBase<Edge>* backward_storage =
1457        new _reader_bits::GraphArcMapStorage<Graph, false, Map>(_graph, map);
1458      _edge_maps.push_back(std::make_pair('-' + caption, backward_storage));
1459      return *this;
1460    }
1461
1462    /// \brief Arc map reading rule
1463    ///
1464    /// Add an arc map reading rule with specialized converter to the
1465    /// reader.
1466    template <typename Map, typename Converter>
1467    GraphReader& arcMap(const std::string& caption, Map& map,
1468                          const Converter& converter = Converter()) {
1469      checkConcept<concepts::WriteMap<Arc, typename Map::Value>, Map>();
1470      _reader_bits::MapStorageBase<Edge>* forward_storage =
1471        new _reader_bits::GraphArcMapStorage<Graph, true, Map, Converter>
1472        (_graph, map, converter);
1473      _edge_maps.push_back(std::make_pair('+' + caption, forward_storage));
1474      _reader_bits::MapStorageBase<Edge>* backward_storage =
1475        new _reader_bits::GraphArcMapStorage<Graph, false, Map, Converter>
1476        (_graph, map, converter);
1477      _edge_maps.push_back(std::make_pair('-' + caption, backward_storage));
1478      return *this;
1479    }
1480
1481    /// \brief Attribute reading rule
1482    ///
1483    /// Add an attribute reading rule to the reader.
1484    template <typename Value>
1485    GraphReader& attribute(const std::string& caption, Value& value) {
1486      _reader_bits::ValueStorageBase* storage =
1487        new _reader_bits::ValueStorage<Value>(value);
1488      _attributes.insert(std::make_pair(caption, storage));
1489      return *this;
1490    }
1491
1492    /// \brief Attribute reading rule
1493    ///
1494    /// Add an attribute reading rule with specialized converter to the
1495    /// reader.
1496    template <typename Value, typename Converter>
1497    GraphReader& attribute(const std::string& caption, Value& value,
1498                             const Converter& converter = Converter()) {
1499      _reader_bits::ValueStorageBase* storage =
1500        new _reader_bits::ValueStorage<Value, Converter>(value, converter);
1501      _attributes.insert(std::make_pair(caption, storage));
1502      return *this;
1503    }
1504
1505    /// \brief Node reading rule
1506    ///
1507    /// Add a node reading rule to reader.
1508    GraphReader& node(const std::string& caption, Node& node) {
1509      typedef _reader_bits::MapLookUpConverter<Node> Converter;
1510      Converter converter(_node_index);
1511      _reader_bits::ValueStorageBase* storage =
1512        new _reader_bits::ValueStorage<Node, Converter>(node, converter);
1513      _attributes.insert(std::make_pair(caption, storage));
1514      return *this;
1515    }
1516
1517    /// \brief Edge reading rule
1518    ///
1519    /// Add an edge reading rule to reader.
1520    GraphReader& edge(const std::string& caption, Edge& edge) {
1521      typedef _reader_bits::MapLookUpConverter<Edge> Converter;
1522      Converter converter(_edge_index);
1523      _reader_bits::ValueStorageBase* storage =
1524        new _reader_bits::ValueStorage<Edge, Converter>(edge, converter);
1525      _attributes.insert(std::make_pair(caption, storage));
1526      return *this;
1527    }
1528
1529    /// \brief Arc reading rule
1530    ///
1531    /// Add an arc reading rule to reader.
1532    GraphReader& arc(const std::string& caption, Arc& arc) {
1533      typedef _reader_bits::GraphArcLookUpConverter<Graph> Converter;
1534      Converter converter(_graph, _edge_index);
1535      _reader_bits::ValueStorageBase* storage =
1536        new _reader_bits::ValueStorage<Arc, Converter>(arc, converter);
1537      _attributes.insert(std::make_pair(caption, storage));
1538      return *this;
1539    }
1540
1541    /// @}
1542
1543    /// \name Select Section by Name
1544    /// @{
1545
1546    /// \brief Set \c \@nodes section to be read
1547    ///
1548    /// Set \c \@nodes section to be read.
1549    GraphReader& nodes(const std::string& caption) {
1550      _nodes_caption = caption;
1551      return *this;
1552    }
1553
1554    /// \brief Set \c \@edges section to be read
1555    ///
1556    /// Set \c \@edges section to be read.
1557    GraphReader& edges(const std::string& caption) {
1558      _edges_caption = caption;
1559      return *this;
1560    }
1561
1562    /// \brief Set \c \@attributes section to be read
1563    ///
1564    /// Set \c \@attributes section to be read.
1565    GraphReader& attributes(const std::string& caption) {
1566      _attributes_caption = caption;
1567      return *this;
1568    }
1569
1570    /// @}
1571
1572    /// \name Using Previously Constructed Node or Edge Set
1573    /// @{
1574
1575    /// \brief Use previously constructed node set
1576    ///
1577    /// Use previously constructed node set, and specify the node
1578    /// label map.
1579    template <typename Map>
1580    GraphReader& useNodes(const Map& map) {
1581      checkConcept<concepts::ReadMap<Node, typename Map::Value>, Map>();
1582      LEMON_ASSERT(!_use_nodes, "Multiple usage of useNodes() member");
1583      _use_nodes = true;
1584      _writer_bits::DefaultConverter<typename Map::Value> converter;
1585      for (NodeIt n(_graph); n != INVALID; ++n) {
1586        _node_index.insert(std::make_pair(converter(map[n]), n));
1587      }
1588      return *this;
1589    }
1590
1591    /// \brief Use previously constructed node set
1592    ///
1593    /// Use previously constructed node set, and specify the node
1594    /// label map and a functor which converts the label map values to
1595    /// \c std::string.
1596    template <typename Map, typename Converter>
1597    GraphReader& useNodes(const Map& map,
1598                            const Converter& converter = Converter()) {
1599      checkConcept<concepts::ReadMap<Node, typename Map::Value>, Map>();
1600      LEMON_ASSERT(!_use_nodes, "Multiple usage of useNodes() member");
1601      _use_nodes = true;
1602      for (NodeIt n(_graph); n != INVALID; ++n) {
1603        _node_index.insert(std::make_pair(converter(map[n]), n));
1604      }
1605      return *this;
1606    }
1607
1608    /// \brief Use previously constructed edge set
1609    ///
1610    /// Use previously constructed edge set, and specify the edge
1611    /// label map.
1612    template <typename Map>
1613    GraphReader& useEdges(const Map& map) {
1614      checkConcept<concepts::ReadMap<Edge, typename Map::Value>, Map>();
1615      LEMON_ASSERT(!_use_edges, "Multiple usage of useEdges() member");
1616      _use_edges = true;
1617      _writer_bits::DefaultConverter<typename Map::Value> converter;
1618      for (EdgeIt a(_graph); a != INVALID; ++a) {
1619        _edge_index.insert(std::make_pair(converter(map[a]), a));
1620      }
1621      return *this;
1622    }
1623
1624    /// \brief Use previously constructed edge set
1625    ///
1626    /// Use previously constructed edge set, and specify the edge
1627    /// label map and a functor which converts the label map values to
1628    /// \c std::string.
1629    template <typename Map, typename Converter>
1630    GraphReader& useEdges(const Map& map,
1631                            const Converter& converter = Converter()) {
1632      checkConcept<concepts::ReadMap<Edge, typename Map::Value>, Map>();
1633      LEMON_ASSERT(!_use_edges, "Multiple usage of useEdges() member");
1634      _use_edges = true;
1635      for (EdgeIt a(_graph); a != INVALID; ++a) {
1636        _edge_index.insert(std::make_pair(converter(map[a]), a));
1637      }
1638      return *this;
1639    }
1640
1641    /// \brief Skip the reading of node section
1642    ///
1643    /// Omit the reading of the node section. This implies that each node
1644    /// map reading rule will be abandoned, and the nodes of the graph
1645    /// will not be constructed, which usually cause that the edge set
1646    /// could not be read due to lack of node name
1647    /// could not be read due to lack of node name resolving.
1648    /// Therefore \c skipEdges() function should also be used, or
1649    /// \c useNodes() should be used to specify the label of the nodes.
1650    GraphReader& skipNodes() {
1651      LEMON_ASSERT(!_skip_nodes, "Skip nodes already set");
1652      _skip_nodes = true;
1653      return *this;
1654    }
1655
1656    /// \brief Skip the reading of edge section
1657    ///
1658    /// Omit the reading of the edge section. This implies that each edge
1659    /// map reading rule will be abandoned, and the edges of the graph
1660    /// will not be constructed.
1661    GraphReader& skipEdges() {
1662      LEMON_ASSERT(!_skip_edges, "Skip edges already set");
1663      _skip_edges = true;
1664      return *this;
1665    }
1666
1667    /// @}
1668
1669  private:
1670
1671    bool readLine() {
1672      std::string str;
1673      while(++line_num, std::getline(*_is, str)) {
1674        line.clear(); line.str(str);
1675        char c;
1676        if (line >> std::ws >> c && c != '#') {
1677          line.putback(c);
1678          return true;
1679        }
1680      }
1681      return false;
1682    }
1683
1684    bool readSuccess() {
1685      return static_cast<bool>(*_is);
1686    }
1687
1688    void skipSection() {
1689      char c;
1690      while (readSuccess() && line >> c && c != '@') {
1691        readLine();
1692      }
1693      if (readSuccess()) {
1694        line.putback(c);
1695      }
1696    }
1697
1698    void readNodes() {
1699
1700      std::vector<int> map_index(_node_maps.size());
1701      int map_num, label_index;
1702
1703      char c;
1704      if (!readLine() || !(line >> c) || c == '@') {
1705        if (readSuccess() && line) line.putback(c);
1706        if (!_node_maps.empty())
1707          throw FormatError("Cannot find map names");
1708        return;
1709      }
1710      line.putback(c);
1711
1712      {
1713        std::map<std::string, int> maps;
1714
1715        std::string map;
1716        int index = 0;
1717        while (_reader_bits::readToken(line, map)) {
1718          if (maps.find(map) != maps.end()) {
1719            std::ostringstream msg;
1720            msg << "Multiple occurence of node map: " << map;
1721            throw FormatError(msg.str());
1722          }
1723          maps.insert(std::make_pair(map, index));
1724          ++index;
1725        }
1726
1727        for (int i = 0; i < static_cast<int>(_node_maps.size()); ++i) {
1728          std::map<std::string, int>::iterator jt =
1729            maps.find(_node_maps[i].first);
1730          if (jt == maps.end()) {
1731            std::ostringstream msg;
1732            msg << "Map not found: " << _node_maps[i].first;
1733            throw FormatError(msg.str());
1734          }
1735          map_index[i] = jt->second;
1736        }
1737
1738        {
1739          std::map<std::string, int>::iterator jt = maps.find("label");
1740          if (jt != maps.end()) {
1741            label_index = jt->second;
1742          } else {
1743            label_index = -1;
1744          }
1745        }
1746        map_num = maps.size();
1747      }
1748
1749      while (readLine() && line >> c && c != '@') {
1750        line.putback(c);
1751
1752        std::vector<std::string> tokens(map_num);
1753        for (int i = 0; i < map_num; ++i) {
1754          if (!_reader_bits::readToken(line, tokens[i])) {
1755            std::ostringstream msg;
1756            msg << "Column not found (" << i + 1 << ")";
1757            throw FormatError(msg.str());
1758          }
1759        }
1760        if (line >> std::ws >> c)
1761          throw FormatError("Extra character at the end of line");
1762
1763        Node n;
1764        if (!_use_nodes) {
1765          n = _graph.addNode();
1766          if (label_index != -1)
1767            _node_index.insert(std::make_pair(tokens[label_index], n));
1768        } else {
1769          if (label_index == -1)
1770            throw FormatError("Label map not found");
1771          typename std::map<std::string, Node>::iterator it =
1772            _node_index.find(tokens[label_index]);
1773          if (it == _node_index.end()) {
1774            std::ostringstream msg;
1775            msg << "Node with label not found: " << tokens[label_index];
1776            throw FormatError(msg.str());
1777          }
1778          n = it->second;
1779        }
1780
1781        for (int i = 0; i < static_cast<int>(_node_maps.size()); ++i) {
1782          _node_maps[i].second->set(n, tokens[map_index[i]]);
1783        }
1784
1785      }
1786      if (readSuccess()) {
1787        line.putback(c);
1788      }
1789    }
1790
1791    void readEdges() {
1792
1793      std::vector<int> map_index(_edge_maps.size());
1794      int map_num, label_index;
1795
1796      char c;
1797      if (!readLine() || !(line >> c) || c == '@') {
1798        if (readSuccess() && line) line.putback(c);
1799        if (!_edge_maps.empty())
1800          throw FormatError("Cannot find map names");
1801        return;
1802      }
1803      line.putback(c);
1804
1805      {
1806        std::map<std::string, int> maps;
1807
1808        std::string map;
1809        int index = 0;
1810        while (_reader_bits::readToken(line, map)) {
1811          if (maps.find(map) != maps.end()) {
1812            std::ostringstream msg;
1813            msg << "Multiple occurence of edge map: " << map;
1814            throw FormatError(msg.str());
1815          }
1816          maps.insert(std::make_pair(map, index));
1817          ++index;
1818        }
1819
1820        for (int i = 0; i < static_cast<int>(_edge_maps.size()); ++i) {
1821          std::map<std::string, int>::iterator jt =
1822            maps.find(_edge_maps[i].first);
1823          if (jt == maps.end()) {
1824            std::ostringstream msg;
1825            msg << "Map not found: " << _edge_maps[i].first;
1826            throw FormatError(msg.str());
1827          }
1828          map_index[i] = jt->second;
1829        }
1830
1831        {
1832          std::map<std::string, int>::iterator jt = maps.find("label");
1833          if (jt != maps.end()) {
1834            label_index = jt->second;
1835          } else {
1836            label_index = -1;
1837          }
1838        }
1839        map_num = maps.size();
1840      }
1841
1842      while (readLine() && line >> c && c != '@') {
1843        line.putback(c);
1844
1845        std::string source_token;
1846        std::string target_token;
1847
1848        if (!_reader_bits::readToken(line, source_token))
1849          throw FormatError("Node u not found");
1850
1851        if (!_reader_bits::readToken(line, target_token))
1852          throw FormatError("Node v not found");
1853
1854        std::vector<std::string> tokens(map_num);
1855        for (int i = 0; i < map_num; ++i) {
1856          if (!_reader_bits::readToken(line, tokens[i])) {
1857            std::ostringstream msg;
1858            msg << "Column not found (" << i + 1 << ")";
1859            throw FormatError(msg.str());
1860          }
1861        }
1862        if (line >> std::ws >> c)
1863          throw FormatError("Extra character at the end of line");
1864
1865        Edge e;
1866        if (!_use_edges) {
1867
1868          typename NodeIndex::iterator it;
1869
1870          it = _node_index.find(source_token);
1871          if (it == _node_index.end()) {
1872            std::ostringstream msg;
1873            msg << "Item not found: " << source_token;
1874            throw FormatError(msg.str());
1875          }
1876          Node source = it->second;
1877
1878          it = _node_index.find(target_token);
1879          if (it == _node_index.end()) {
1880            std::ostringstream msg;
1881            msg << "Item not found: " << target_token;
1882            throw FormatError(msg.str());
1883          }
1884          Node target = it->second;
1885
1886          e = _graph.addEdge(source, target);
1887          if (label_index != -1)
1888            _edge_index.insert(std::make_pair(tokens[label_index], e));
1889        } else {
1890          if (label_index == -1)
1891            throw FormatError("Label map not found");
1892          typename std::map<std::string, Edge>::iterator it =
1893            _edge_index.find(tokens[label_index]);
1894          if (it == _edge_index.end()) {
1895            std::ostringstream msg;
1896            msg << "Edge with label not found: " << tokens[label_index];
1897            throw FormatError(msg.str());
1898          }
1899          e = it->second;
1900        }
1901
1902        for (int i = 0; i < static_cast<int>(_edge_maps.size()); ++i) {
1903          _edge_maps[i].second->set(e, tokens[map_index[i]]);
1904        }
1905
1906      }
1907      if (readSuccess()) {
1908        line.putback(c);
1909      }
1910    }
1911
1912    void readAttributes() {
1913
1914      std::set<std::string> read_attr;
1915
1916      char c;
1917      while (readLine() && line >> c && c != '@') {
1918        line.putback(c);
1919
1920        std::string attr, token;
1921        if (!_reader_bits::readToken(line, attr))
1922          throw FormatError("Attribute name not found");
1923        if (!_reader_bits::readToken(line, token))
1924          throw FormatError("Attribute value not found");
1925        if (line >> c)
1926          throw FormatError("Extra character at the end of line");
1927
1928        {
1929          std::set<std::string>::iterator it = read_attr.find(attr);
1930          if (it != read_attr.end()) {
1931            std::ostringstream msg;
1932            msg << "Multiple occurence of attribute: " << attr;
1933            throw FormatError(msg.str());
1934          }
1935          read_attr.insert(attr);
1936        }
1937
1938        {
1939          typename Attributes::iterator it = _attributes.lower_bound(attr);
1940          while (it != _attributes.end() && it->first == attr) {
1941            it->second->set(token);
1942            ++it;
1943          }
1944        }
1945
1946      }
1947      if (readSuccess()) {
1948        line.putback(c);
1949      }
1950      for (typename Attributes::iterator it = _attributes.begin();
1951           it != _attributes.end(); ++it) {
1952        if (read_attr.find(it->first) == read_attr.end()) {
1953          std::ostringstream msg;
1954          msg << "Attribute not found: " << it->first;
1955          throw FormatError(msg.str());
1956        }
1957      }
1958    }
1959
1960  public:
1961
1962    /// \name Execution of the Reader
1963    /// @{
1964
1965    /// \brief Start the batch processing
1966    ///
1967    /// This function starts the batch processing
1968    void run() {
1969
1970      LEMON_ASSERT(_is != 0, "This reader assigned to an other reader");
1971
1972      bool nodes_done = _skip_nodes;
1973      bool edges_done = _skip_edges;
1974      bool attributes_done = false;
1975
1976      line_num = 0;
1977      readLine();
1978      skipSection();
1979
1980      while (readSuccess()) {
1981        try {
1982          char c;
1983          std::string section, caption;
1984          line >> c;
1985          _reader_bits::readToken(line, section);
1986          _reader_bits::readToken(line, caption);
1987
1988          if (line >> c)
1989            throw FormatError("Extra character at the end of line");
1990
1991          if (section == "nodes" && !nodes_done) {
1992            if (_nodes_caption.empty() || _nodes_caption == caption) {
1993              readNodes();
1994              nodes_done = true;
1995            }
1996          } else if ((section == "edges" || section == "arcs") &&
1997                     !edges_done) {
1998            if (_edges_caption.empty() || _edges_caption == caption) {
1999              readEdges();
2000              edges_done = true;
2001            }
2002          } else if (section == "attributes" && !attributes_done) {
2003            if (_attributes_caption.empty() || _attributes_caption == caption) {
2004              readAttributes();
2005              attributes_done = true;
2006            }
2007          } else {
2008            readLine();
2009            skipSection();
2010          }
2011        } catch (FormatError& error) {
2012          error.line(line_num);
2013          error.file(_filename);
2014          throw;
2015        }
2016      }
2017
2018      if (!nodes_done) {
2019        throw FormatError("Section @nodes not found");
2020      }
2021
2022      if (!edges_done) {
2023        throw FormatError("Section @edges not found");
2024      }
2025
2026      if (!attributes_done && !_attributes.empty()) {
2027        throw FormatError("Section @attributes not found");
2028      }
2029
2030    }
2031
2032    /// @}
2033
2034  };
2035
2036  /// \brief Return a \ref GraphReader class
2037  ///
2038  /// This function just returns a \ref GraphReader class.
2039  /// \relates GraphReader
2040  template <typename Graph>
2041  GraphReader<Graph> graphReader(Graph& graph, std::istream& is) {
2042    GraphReader<Graph> tmp(graph, is);
2043    return tmp;
2044  }
2045
2046  /// \brief Return a \ref GraphReader class
2047  ///
2048  /// This function just returns a \ref GraphReader class.
2049  /// \relates GraphReader
2050  template <typename Graph>
2051  GraphReader<Graph> graphReader(Graph& graph, const std::string& fn) {
2052    GraphReader<Graph> tmp(graph, fn);
2053    return tmp;
2054  }
2055
2056  /// \brief Return a \ref GraphReader class
2057  ///
2058  /// This function just returns a \ref GraphReader class.
2059  /// \relates GraphReader
2060  template <typename Graph>
2061  GraphReader<Graph> graphReader(Graph& graph, const char* fn) {
2062    GraphReader<Graph> tmp(graph, fn);
2063    return tmp;
2064  }
2065
2066  class SectionReader;
2067
2068  SectionReader sectionReader(std::istream& is);
2069  SectionReader sectionReader(const std::string& fn);
2070  SectionReader sectionReader(const char* fn);
2071
2072  /// \ingroup lemon_io
2073  ///
2074  /// \brief Section reader class
2075  ///
2076  /// In the \ref lgf-format "LGF" file extra sections can be placed,
2077  /// which contain any data in arbitrary format. Such sections can be
2078  /// read with this class. A reading rule can be added to the class
2079  /// with two different functions. With the \c sectionLines() function a
2080  /// functor can process the section line-by-line, while with the \c
2081  /// sectionStream() member the section can be read from an input
2082  /// stream.
2083  class SectionReader {
2084  private:
2085
2086    std::istream* _is;
2087    bool local_is;
2088    std::string _filename;
2089
2090    typedef std::map<std::string, _reader_bits::Section*> Sections;
2091    Sections _sections;
2092
2093    int line_num;
2094    std::istringstream line;
2095
2096  public:
2097
2098    /// \brief Constructor
2099    ///
2100    /// Construct a section reader, which reads from the given input
2101    /// stream.
2102    SectionReader(std::istream& is)
2103      : _is(&is), local_is(false) {}
2104
2105    /// \brief Constructor
2106    ///
2107    /// Construct a section reader, which reads from the given file.
2108    SectionReader(const std::string& fn)
2109      : _is(new std::ifstream(fn.c_str())), local_is(true),
2110        _filename(fn) {
2111      if (!(*_is)) {
2112        delete _is;
2113        throw IoError("Cannot open file", fn);
2114      }
2115    }
2116
2117    /// \brief Constructor
2118    ///
2119    /// Construct a section reader, which reads from the given file.
2120    SectionReader(const char* fn)
2121      : _is(new std::ifstream(fn)), local_is(true),
2122        _filename(fn) {
2123      if (!(*_is)) {
2124        delete _is;
2125        throw IoError("Cannot open file", fn);
2126      }
2127    }
2128
2129    /// \brief Destructor
2130    ~SectionReader() {
2131      for (Sections::iterator it = _sections.begin();
2132           it != _sections.end(); ++it) {
2133        delete it->second;
2134      }
2135
2136      if (local_is) {
2137        delete _is;
2138      }
2139
2140    }
2141
2142  private:
2143
2144    friend SectionReader sectionReader(std::istream& is);
2145    friend SectionReader sectionReader(const std::string& fn);
2146    friend SectionReader sectionReader(const char* fn);
2147
2148    SectionReader(SectionReader& other)
2149      : _is(other._is), local_is(other.local_is) {
2150
2151      other._is = 0;
2152      other.local_is = false;
2153
2154      _sections.swap(other._sections);
2155    }
2156
2157    SectionReader& operator=(const SectionReader&);
2158
2159  public:
2160
2161    /// \name Section Readers
2162    /// @{
2163
2164    /// \brief Add a section processor with line oriented reading
2165    ///
2166    /// The first parameter is the type descriptor of the section, the
2167    /// second is a functor, which takes just one \c std::string
2168    /// parameter. At the reading process, each line of the section
2169    /// will be given to the functor object. However, the empty lines
2170    /// and the comment lines are filtered out, and the leading
2171    /// whitespaces are trimmed from each processed string.
2172    ///
2173    /// For example let's see a section, which contain several
2174    /// integers, which should be inserted into a vector.
2175    ///\code
2176    ///  @numbers
2177    ///  12 45 23
2178    ///  4
2179    ///  23 6
2180    ///\endcode
2181    ///
2182    /// The functor is implemented as a struct:
2183    ///\code
2184    ///  struct NumberSection {
2185    ///    std::vector<int>& _data;
2186    ///    NumberSection(std::vector<int>& data) : _data(data) {}
2187    ///    void operator()(const std::string& line) {
2188    ///      std::istringstream ls(line);
2189    ///      int value;
2190    ///      while (ls >> value) _data.push_back(value);
2191    ///    }
2192    ///  };
2193    ///
2194    ///  // ...
2195    ///
2196    ///  reader.sectionLines("numbers", NumberSection(vec));
2197    ///\endcode
2198    template <typename Functor>
2199    SectionReader& sectionLines(const std::string& type, Functor functor) {
2200      LEMON_ASSERT(!type.empty(), "Type is empty.");
2201      LEMON_ASSERT(_sections.find(type) == _sections.end(),
2202                   "Multiple reading of section.");
2203      _sections.insert(std::make_pair(type,
2204        new _reader_bits::LineSection<Functor>(functor)));
2205      return *this;
2206    }
2207
2208
2209    /// \brief Add a section processor with stream oriented reading
2210    ///
2211    /// The first parameter is the type of the section, the second is
2212    /// a functor, which takes an \c std::istream& and an \c int&
2213    /// parameter, the latter regard to the line number of stream. The
2214    /// functor can read the input while the section go on, and the
2215    /// line number should be modified accordingly.
2216    template <typename Functor>
2217    SectionReader& sectionStream(const std::string& type, Functor functor) {
2218      LEMON_ASSERT(!type.empty(), "Type is empty.");
2219      LEMON_ASSERT(_sections.find(type) == _sections.end(),
2220                   "Multiple reading of section.");
2221      _sections.insert(std::make_pair(type,
2222         new _reader_bits::StreamSection<Functor>(functor)));
2223      return *this;
2224    }
2225
2226    /// @}
2227
2228  private:
2229
2230    bool readLine() {
2231      std::string str;
2232      while(++line_num, std::getline(*_is, str)) {
2233        line.clear(); line.str(str);
2234        char c;
2235        if (line >> std::ws >> c && c != '#') {
2236          line.putback(c);
2237          return true;
2238        }
2239      }
2240      return false;
2241    }
2242
2243    bool readSuccess() {
2244      return static_cast<bool>(*_is);
2245    }
2246
2247    void skipSection() {
2248      char c;
2249      while (readSuccess() && line >> c && c != '@') {
2250        readLine();
2251      }
2252      if (readSuccess()) {
2253        line.putback(c);
2254      }
2255    }
2256
2257  public:
2258
2259
2260    /// \name Execution of the Reader
2261    /// @{
2262
2263    /// \brief Start the batch processing
2264    ///
2265    /// This function starts the batch processing.
2266    void run() {
2267
2268      LEMON_ASSERT(_is != 0, "This reader assigned to an other reader");
2269
2270      std::set<std::string> extra_sections;
2271
2272      line_num = 0;
2273      readLine();
2274      skipSection();
2275
2276      while (readSuccess()) {
2277        try {
2278          char c;
2279          std::string section, caption;
2280          line >> c;
2281          _reader_bits::readToken(line, section);
2282          _reader_bits::readToken(line, caption);
2283
2284          if (line >> c)
2285            throw FormatError("Extra character at the end of line");
2286
2287          if (extra_sections.find(section) != extra_sections.end()) {
2288            std::ostringstream msg;
2289            msg << "Multiple occurence of section: " << section;
2290            throw FormatError(msg.str());
2291          }
2292          Sections::iterator it = _sections.find(section);
2293          if (it != _sections.end()) {
2294            extra_sections.insert(section);
2295            it->second->process(*_is, line_num);
2296          }
2297          readLine();
2298          skipSection();
2299        } catch (FormatError& error) {
2300          error.line(line_num);
2301          error.file(_filename);
2302          throw;
2303        }
2304      }
2305      for (Sections::iterator it = _sections.begin();
2306           it != _sections.end(); ++it) {
2307        if (extra_sections.find(it->first) == extra_sections.end()) {
2308          std::ostringstream os;
2309          os << "Cannot find section: " << it->first;
2310          throw FormatError(os.str());
2311        }
2312      }
2313    }
2314
2315    /// @}
2316
2317  };
2318
2319  /// \brief Return a \ref SectionReader class
2320  ///
2321  /// This function just returns a \ref SectionReader class.
2322  /// \relates SectionReader
2323  inline SectionReader sectionReader(std::istream& is) {
2324    SectionReader tmp(is);
2325    return tmp;
2326  }
2327
2328  /// \brief Return a \ref SectionReader class
2329  ///
2330  /// This function just returns a \ref SectionReader class.
2331  /// \relates SectionReader
2332  inline SectionReader sectionReader(const std::string& fn) {
2333    SectionReader tmp(fn);
2334    return tmp;
2335  }
2336
2337  /// \brief Return a \ref SectionReader class
2338  ///
2339  /// This function just returns a \ref SectionReader class.
2340  /// \relates SectionReader
2341  inline SectionReader sectionReader(const char* fn) {
2342    SectionReader tmp(fn);
2343    return tmp;
2344  }
2345
2346  /// \ingroup lemon_io
2347  ///
2348  /// \brief Reader for the contents of the \ref lgf-format "LGF" file
2349  ///
2350  /// This class can be used to read the sections, the map names and
2351  /// the attributes from a file. Usually, the LEMON programs know
2352  /// that, which type of graph, which maps and which attributes
2353  /// should be read from a file, but in general tools (like glemon)
2354  /// the contents of an LGF file should be guessed somehow. This class
2355  /// reads the graph and stores the appropriate information for
2356  /// reading the graph.
2357  ///
2358  ///\code
2359  /// LgfContents contents("graph.lgf");
2360  /// contents.run();
2361  ///
2362  /// // Does it contain any node section and arc section?
2363  /// if (contents.nodeSectionNum() == 0 || contents.arcSectionNum()) {
2364  ///   std::cerr << "Failure, cannot find graph." << std::endl;
2365  ///   return -1;
2366  /// }
2367  /// std::cout << "The name of the default node section: "
2368  ///           << contents.nodeSection(0) << std::endl;
2369  /// std::cout << "The number of the arc maps: "
2370  ///           << contents.arcMaps(0).size() << std::endl;
2371  /// std::cout << "The name of second arc map: "
2372  ///           << contents.arcMaps(0)[1] << std::endl;
2373  ///\endcode
2374  class LgfContents {
2375  private:
2376
2377    std::istream* _is;
2378    bool local_is;
2379
2380    std::vector<std::string> _node_sections;
2381    std::vector<std::string> _edge_sections;
2382    std::vector<std::string> _attribute_sections;
2383    std::vector<std::string> _extra_sections;
2384
2385    std::vector<bool> _arc_sections;
2386
2387    std::vector<std::vector<std::string> > _node_maps;
2388    std::vector<std::vector<std::string> > _edge_maps;
2389
2390    std::vector<std::vector<std::string> > _attributes;
2391
2392
2393    int line_num;
2394    std::istringstream line;
2395
2396  public:
2397
2398    /// \brief Constructor
2399    ///
2400    /// Construct an \e LGF contents reader, which reads from the given
2401    /// input stream.
2402    LgfContents(std::istream& is)
2403      : _is(&is), local_is(false) {}
2404
2405    /// \brief Constructor
2406    ///
2407    /// Construct an \e LGF contents reader, which reads from the given
2408    /// file.
2409    LgfContents(const std::string& fn)
2410      : _is(new std::ifstream(fn.c_str())), local_is(true) {
2411      if (!(*_is)) {
2412        delete _is;
2413        throw IoError("Cannot open file", fn);
2414      }
2415    }
2416
2417    /// \brief Constructor
2418    ///
2419    /// Construct an \e LGF contents reader, which reads from the given
2420    /// file.
2421    LgfContents(const char* fn)
2422      : _is(new std::ifstream(fn)), local_is(true) {
2423      if (!(*_is)) {
2424        delete _is;
2425        throw IoError("Cannot open file", fn);
2426      }
2427    }
2428
2429    /// \brief Destructor
2430    ~LgfContents() {
2431      if (local_is) delete _is;
2432    }
2433
2434  private:
2435
2436    LgfContents(const LgfContents&);
2437    LgfContents& operator=(const LgfContents&);
2438
2439  public:
2440
2441
2442    /// \name Node Sections
2443    /// @{
2444
2445    /// \brief Gives back the number of node sections in the file.
2446    ///
2447    /// Gives back the number of node sections in the file.
2448    int nodeSectionNum() const {
2449      return _node_sections.size();
2450    }
2451
2452    /// \brief Returns the node section name at the given position.
2453    ///
2454    /// Returns the node section name at the given position.
2455    const std::string& nodeSection(int i) const {
2456      return _node_sections[i];
2457    }
2458
2459    /// \brief Gives back the node maps for the given section.
2460    ///
2461    /// Gives back the node maps for the given section.
2462    const std::vector<std::string>& nodeMapNames(int i) const {
2463      return _node_maps[i];
2464    }
2465
2466    /// @}
2467
2468    /// \name Arc/Edge Sections
2469    /// @{
2470
2471    /// \brief Gives back the number of arc/edge sections in the file.
2472    ///
2473    /// Gives back the number of arc/edge sections in the file.
2474    /// \note It is synonym of \c edgeSectionNum().
2475    int arcSectionNum() const {
2476      return _edge_sections.size();
2477    }
2478
2479    /// \brief Returns the arc/edge section name at the given position.
2480    ///
2481    /// Returns the arc/edge section name at the given position.
2482    /// \note It is synonym of \c edgeSection().
2483    const std::string& arcSection(int i) const {
2484      return _edge_sections[i];
2485    }
2486
2487    /// \brief Gives back the arc/edge maps for the given section.
2488    ///
2489    /// Gives back the arc/edge maps for the given section.
2490    /// \note It is synonym of \c edgeMapNames().
2491    const std::vector<std::string>& arcMapNames(int i) const {
2492      return _edge_maps[i];
2493    }
2494
2495    /// @}
2496
2497    /// \name Synonyms
2498    /// @{
2499
2500    /// \brief Gives back the number of arc/edge sections in the file.
2501    ///
2502    /// Gives back the number of arc/edge sections in the file.
2503    /// \note It is synonym of \c arcSectionNum().
2504    int edgeSectionNum() const {
2505      return _edge_sections.size();
2506    }
2507
2508    /// \brief Returns the section name at the given position.
2509    ///
2510    /// Returns the section name at the given position.
2511    /// \note It is synonym of \c arcSection().
2512    const std::string& edgeSection(int i) const {
2513      return _edge_sections[i];
2514    }
2515
2516    /// \brief Gives back the edge maps for the given section.
2517    ///
2518    /// Gives back the edge maps for the given section.
2519    /// \note It is synonym of \c arcMapNames().
2520    const std::vector<std::string>& edgeMapNames(int i) const {
2521      return _edge_maps[i];
2522    }
2523
2524    /// @}
2525
2526    /// \name Attribute Sections
2527    /// @{
2528
2529    /// \brief Gives back the number of attribute sections in the file.
2530    ///
2531    /// Gives back the number of attribute sections in the file.
2532    int attributeSectionNum() const {
2533      return _attribute_sections.size();
2534    }
2535
2536    /// \brief Returns the attribute section name at the given position.
2537    ///
2538    /// Returns the attribute section name at the given position.
2539    const std::string& attributeSectionNames(int i) const {
2540      return _attribute_sections[i];
2541    }
2542
2543    /// \brief Gives back the attributes for the given section.
2544    ///
2545    /// Gives back the attributes for the given section.
2546    const std::vector<std::string>& attributes(int i) const {
2547      return _attributes[i];
2548    }
2549
2550    /// @}
2551
2552    /// \name Extra Sections
2553    /// @{
2554
2555    /// \brief Gives back the number of extra sections in the file.
2556    ///
2557    /// Gives back the number of extra sections in the file.
2558    int extraSectionNum() const {
2559      return _extra_sections.size();
2560    }
2561
2562    /// \brief Returns the extra section type at the given position.
2563    ///
2564    /// Returns the section type at the given position.
2565    const std::string& extraSection(int i) const {
2566      return _extra_sections[i];
2567    }
2568
2569    /// @}
2570
2571  private:
2572
2573    bool readLine() {
2574      std::string str;
2575      while(++line_num, std::getline(*_is, str)) {
2576        line.clear(); line.str(str);
2577        char c;
2578        if (line >> std::ws >> c && c != '#') {
2579          line.putback(c);
2580          return true;
2581        }
2582      }
2583      return false;
2584    }
2585
2586    bool readSuccess() {
2587      return static_cast<bool>(*_is);
2588    }
2589
2590    void skipSection() {
2591      char c;
2592      while (readSuccess() && line >> c && c != '@') {
2593        readLine();
2594      }
2595      if (readSuccess()) {
2596        line.putback(c);
2597      }
2598    }
2599
2600    void readMaps(std::vector<std::string>& maps) {
2601      char c;
2602      if (!readLine() || !(line >> c) || c == '@') {
2603        if (readSuccess() && line) line.putback(c);
2604        return;
2605      }
2606      line.putback(c);
2607      std::string map;
2608      while (_reader_bits::readToken(line, map)) {
2609        maps.push_back(map);
2610      }
2611    }
2612
2613    void readAttributes(std::vector<std::string>& attrs) {
2614      readLine();
2615      char c;
2616      while (readSuccess() && line >> c && c != '@') {
2617        line.putback(c);
2618        std::string attr;
2619        _reader_bits::readToken(line, attr);
2620        attrs.push_back(attr);
2621        readLine();
2622      }
2623      line.putback(c);
2624    }
2625
2626  public:
2627
2628    /// \name Execution of the Contents Reader
2629    /// @{
2630
2631    /// \brief Starts the reading
2632    ///
2633    /// This function starts the reading.
2634    void run() {
2635
2636      readLine();
2637      skipSection();
2638
2639      while (readSuccess()) {
2640
2641        char c;
2642        line >> c;
2643
2644        std::string section, caption;
2645        _reader_bits::readToken(line, section);
2646        _reader_bits::readToken(line, caption);
2647
2648        if (section == "nodes") {
2649          _node_sections.push_back(caption);
2650          _node_maps.push_back(std::vector<std::string>());
2651          readMaps(_node_maps.back());
2652          readLine(); skipSection();
2653        } else if (section == "arcs" || section == "edges") {
2654          _edge_sections.push_back(caption);
2655          _arc_sections.push_back(section == "arcs");
2656          _edge_maps.push_back(std::vector<std::string>());
2657          readMaps(_edge_maps.back());
2658          readLine(); skipSection();
2659        } else if (section == "attributes") {
2660          _attribute_sections.push_back(caption);
2661          _attributes.push_back(std::vector<std::string>());
2662          readAttributes(_attributes.back());
2663        } else {
2664          _extra_sections.push_back(section);
2665          readLine(); skipSection();
2666        }
2667      }
2668    }
2669
2670    /// @}
2671
2672  };
2673}
2674
2675#endif
Note: See TracBrowser for help on using the repository browser.