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