1 // -*- mode: C++; indent-tabs-mode: nil; c-basic-offset: 2; -*-
6 @brief Provides a simple UTF-8 encoded string
13 # ifdef HAVE_SYS_TYPES_H
14 # include <sys/types.h>
23 //! The number of bytes to skip to find the next character in the string
24 const char g_utf8_skip[256] = {
25 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
26 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
27 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
28 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
29 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
30 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
31 2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,
32 3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,4,4,4,4,4,4,4,4,5,5,5,5,6,6,1,1
36 typedef uint32_t unichar;
38 typedef u_int32_t unichar;
41 //! The iterator type for ustring
43 Note this is not a random access iterator but a bidirectional one, since all
44 index operations need to iterate over the UTF-8 data. Use std::advance() to
45 move to a certain position.
47 A writeable iterator isn't provided because: The number of bytes of the old
48 UTF-8 character and the new one to write could be different. Therefore, any
49 write operation would invalidate all other iterators pointing into the same
53 class ustring_Iterator
56 typedef std::bidirectional_iterator_tag iterator_category;
57 typedef unichar value_type;
58 typedef std::string::difference_type difference_type;
59 typedef value_type reference;
62 inline ustring_Iterator() {}
63 inline ustring_Iterator(const ustring_Iterator<std::string::iterator>&
64 other) : _pos(other.base()) {}
66 inline value_type operator*() const {
67 // get a unicode character from the iterator's position
69 // get an iterator to the internal string
70 std::string::const_iterator pos = _pos;
72 unichar result = static_cast<unsigned char>(*pos);
74 // if its not a 7-bit ascii character
75 if((result & 0x80) != 0) {
76 // len is the number of bytes this character takes up in the string
77 unsigned char len = g_utf8_skip[result];
78 result &= 0x7F >> len;
82 result |= static_cast<unsigned char>(*++pos) & 0x3F;
89 inline ustring_Iterator<T> & operator++() {
90 pos_ += g_utf8_skip[static_cast<unsigned char>(*pos_)];
93 inline ustring_Iterator<T> & operator--() {
94 do { --_pos; } while((*_pos & '\xC0') == '\x80');
98 explicit inline ustring_Iterator(T pos) : _pos(pos) {}
99 inline T base() const { return _pos; }
105 //! This class provides a simple wrapper to a std::string that is encoded as
108 This class does <b>not</b> handle extended 8-bit ASCII charsets like
111 More info on Unicode and UTF-8 can be found here:
112 http://www.cl.cam.ac.uk/~mgk25/unicode.html
114 This does not subclass std::string, because std::string was intended to be a
115 final class. For instance, it does not have a virtual destructor.
121 typedef std::string::size_type size_type;
122 typedef std::string::difference_type difference_type;
124 typedef unichar value_type;
125 typedef unichar & reference;
126 typedef const unichar & const_reference;
128 typedef ustring_Iterator<std::string::iterator> iterator;
129 typedef ustring_Iterator<std::string::const_iterator> const_iterator;
131 static const size_type npos = std::string::npos;
138 ustring(const ustring& other);
139 ustring& operator=(const ustring& other);
140 ustring(const std::string& src);
141 ustring::ustring(const char* src);
148 #endif // __ustring_hh