1//
2// TextBufferIterator.h
3//
4// Library: Foundation
5// Package: Text
6// Module: TextBufferIterator
7//
8// Definition of the TextBufferIterator class.
9//
10// Copyright (c) 2010, Applied Informatics Software Engineering GmbH.
11// and Contributors.
12//
13// SPDX-License-Identifier: BSL-1.0
14//
15
16
17#ifndef Foundation_TextBufferIterator_INCLUDED
18#define Foundation_TextBufferIterator_INCLUDED
19
20
21#include "Poco/Foundation.h"
22#include <cstdlib>
23
24
25namespace Poco {
26
27
28class TextEncoding;
29
30
31class Foundation_API TextBufferIterator
32 /// An unidirectional iterator for iterating over characters in a buffer.
33 /// The TextBufferIterator uses a TextEncoding object to
34 /// work with multi-byte character encodings like UTF-8.
35 /// Characters are reported in Unicode.
36 ///
37 /// Example: Count the number of UTF-8 characters in a buffer.
38 ///
39 /// UTF8Encoding utf8Encoding;
40 /// char buffer[] = "...";
41 /// TextBufferIterator it(buffer, utf8Encoding);
42 /// TextBufferIterator end(it.end());
43 /// int n = 0;
44 /// while (it != end) { ++n; ++it; }
45 ///
46 /// NOTE: When an UTF-16 encoding is used, surrogate pairs will be
47 /// reported as two separate characters, due to restrictions of
48 /// the TextEncoding class.
49 ///
50 /// For iterating over the characters in a std::string, see the
51 /// TextIterator class.
52{
53public:
54 TextBufferIterator();
55 /// Creates an uninitialized TextBufferIterator.
56
57 TextBufferIterator(const char* begin, const TextEncoding& encoding);
58 /// Creates a TextBufferIterator for the given buffer, which must be 0-terminated.
59 /// The encoding object must not be deleted as long as the iterator
60 /// is in use.
61
62 TextBufferIterator(const char* begin, std::size_t size, const TextEncoding& encoding);
63 /// Creates a TextBufferIterator for the given buffer with the given size.
64 /// The encoding object must not be deleted as long as the iterator
65 /// is in use.
66
67 TextBufferIterator(const char* begin, const char* end, const TextEncoding& encoding);
68 /// Creates a TextBufferIterator for the given range.
69 /// The encoding object must not be deleted as long as the iterator
70 /// is in use.
71
72 TextBufferIterator(const char* end);
73 /// Creates an end TextBufferIterator for the given buffer.
74
75 ~TextBufferIterator();
76 /// Destroys the TextBufferIterator.
77
78 TextBufferIterator(const TextBufferIterator& it);
79 /// Copy constructor.
80
81 TextBufferIterator& operator = (const TextBufferIterator& it);
82 /// Assignment operator.
83
84 void swap(TextBufferIterator& it);
85 /// Swaps the iterator with another one.
86
87 int operator * () const;
88 /// Returns the Unicode value of the current character.
89 /// If there is no valid character at the current position,
90 /// -1 is returned.
91
92 TextBufferIterator& operator ++ ();
93 /// Prefix increment operator.
94
95 TextBufferIterator operator ++ (int);
96 /// Postfix increment operator.
97
98 bool operator == (const TextBufferIterator& it) const;
99 /// Compares two iterators for equality.
100
101 bool operator != (const TextBufferIterator& it) const;
102 /// Compares two iterators for inequality.
103
104 TextBufferIterator end() const;
105 /// Returns the end iterator for the range handled
106 /// by the iterator.
107
108private:
109 const TextEncoding* _pEncoding;
110 const char* _it;
111 const char* _end;
112};
113
114
115//
116// inlines
117//
118inline bool TextBufferIterator::operator == (const TextBufferIterator& it) const
119{
120 return _it == it._it;
121}
122
123
124inline bool TextBufferIterator::operator != (const TextBufferIterator& it) const
125{
126 return _it != it._it;
127}
128
129
130inline void swap(TextBufferIterator& it1, TextBufferIterator& it2)
131{
132 it1.swap(it2);
133}
134
135
136inline TextBufferIterator TextBufferIterator::end() const
137{
138 return TextBufferIterator(_end);
139}
140
141
142} // namespace Poco
143
144
145#endif // Foundation_TextBufferIterator_INCLUDED
146