1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
|
/*
** SWISH++
** file_list.h
**
** Copyright (C) 1998 Paul J. Lucas
**
** This program is free software; you can redistribute it and/or modify
** it under the terms of the GNU General Public License as published by
** the Free Software Foundation; either version 2 of the License, or
** (at your option) any later version.
**
** This program is distributed in the hope that it will be useful,
** but WITHOUT ANY WARRANTY; without even the implied warranty of
** MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
** GNU General Public License for more details.
**
** You should have received a copy of the GNU General Public License
** along with this program; if not, write to the Free Software
** Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#ifndef file_list_H
#define file_list_H
// standard
#include <cstddef> /* for ptrdiff_t */
#include <iterator>
// local
#include "index_segment.h"
#include "word_info.h"
//*****************************************************************************
//
// SYNOPSIS
//
class file_list
//
// DESCRIPTION
//
// This class, given a index_segment::const_iterator, accesses the list of
// files the word is in. Once an instance is created, the list of files
// can be iterated over.
//
// SEE ALSO
//
// index_segment.h
// word_info.h
// index.c write_full_index() for a description of the index file
// format.
//
//*****************************************************************************
{
typedef unsigned char byte; // for convenience
public:
////////// typedefs ///////////////////////////////////////////////////
typedef int size_type;
typedef ptrdiff_t difference_type;
typedef word_info::file value_type;
typedef value_type const* const_pointer;
typedef value_type const& const_reference;
////////// constructors ///////////////////////////////////////////////
file_list( index_segment::const_iterator const &iter ) :
ptr_( reinterpret_cast<byte const*>( *iter ) ),
size_( -1 ) // -1 = "haven't computed yet"
{
while ( *ptr_++ ) ; // skip past word
}
////////// iterators //////////////////////////////////////////////////
class const_iterator;
friend class const_iterator;
class const_iterator :
public std::iterator< std::forward_iterator_tag, value_type > {
public:
const_iterator() { }
const_reference operator* () const { return v_; }
const_pointer operator->() const { return &v_; }
const_iterator& operator++();
const_iterator operator++(int) {
const_iterator const temp = *this;
return ++*this, temp;
}
friend bool
operator==( const_iterator const &i, const_iterator const &j ) {
return i.c_ == j.c_;
}
friend bool
operator!=( const_iterator const &i, const_iterator const &j ) {
return !( i == j );
}
// default copy constructor is OK
// default assignment operator is OK
private:
const_iterator( byte const *p ) : c_( p ) {
if ( c_ )
operator++();
}
byte const *c_;
value_type v_;
static byte const end_value;
friend class file_list;
};
////////// member functions ///////////////////////////////////////////
const_iterator begin() const { return const_iterator( ptr_ ); }
const_iterator end() const { return const_iterator( 0 ); }
size_type size() const;
private:
byte const *ptr_;
mutable size_type size_;
size_type calc_size() const;
};
////////// inlines ////////////////////////////////////////////////////////////
inline file_list::size_type file_list::size() const {
return size_ != -1 ? size_ : calc_size();
}
#endif /* file_list_H */
/* vim:set noet sw=8 ts=8: */
|
