Commit | Line | Data |
---|---|---|
467175ab VS |
1 | /////////////////////////////////////////////////////////////////////////////// |
2 | // Name: wx/stringops.h | |
3 | // Purpose: implementation of wxString primitive operations | |
4 | // Author: Vaclav Slavik | |
5 | // Modified by: | |
6 | // Created: 2007-04-16 | |
7 | // RCS-ID: $Id$ | |
8 | // Copyright: (c) 2007 REA Elektronik GmbH | |
9 | // Licence: wxWindows licence | |
10 | /////////////////////////////////////////////////////////////////////////////// | |
11 | ||
12 | #ifndef _WX_WXSTRINGOPS_H__ | |
13 | #define _WX_WXSTRINGOPS_H__ | |
14 | ||
15 | #include "wx/chartype.h" | |
16 | #include "wx/stringimpl.h" | |
17 | #include "wx/unichar.h" | |
04d29fda | 18 | #include "wx/buffer.h" |
467175ab VS |
19 | |
20 | // This header contains wxStringOperations "namespace" class that implements | |
21 | // elementary operations on string data as static methods; wxString methods and | |
22 | // iterators are implemented in terms of it. Two implementations are available, | |
23 | // one for UTF-8 encoded char* string and one for "raw" wchar_t* strings (or | |
24 | // char* in ANSI build). | |
25 | ||
26 | // FIXME-UTF8: only wchar after we remove ANSI build | |
27 | #if wxUSE_UNICODE_WCHAR || !wxUSE_UNICODE | |
28 | struct WXDLLIMPEXP_BASE wxStringOperationsWchar | |
29 | { | |
30 | // moves the iterator to the next Unicode character | |
5b119b8b VZ |
31 | template <typename Iterator> |
32 | static void IncIter(Iterator& i) { ++i; } | |
467175ab VS |
33 | |
34 | // moves the iterator to the previous Unicode character | |
5b119b8b VZ |
35 | template <typename Iterator> |
36 | static void DecIter(Iterator& i) { --i; } | |
467175ab VS |
37 | |
38 | // moves the iterator by n Unicode characters | |
5b119b8b VZ |
39 | template <typename Iterator> |
40 | static Iterator AddToIter(const Iterator& i, ptrdiff_t n) | |
467175ab VS |
41 | { return i + n; } |
42 | ||
43 | // returns distance of the two iterators in Unicode characters | |
5b119b8b VZ |
44 | template <typename Iterator> |
45 | static ptrdiff_t DiffIters(const Iterator& i1, const Iterator& i2) | |
467175ab VS |
46 | { return i1 - i2; } |
47 | ||
48 | // encodes the character to a form used to represent it in internal | |
49 | // representation (returns a string in UTF8 version) | |
50 | static wxChar EncodeChar(const wxUniChar& ch) { return (wxChar)ch; } | |
51 | ||
52 | static wxUniChar DecodeChar(const wxStringImpl::const_iterator& i) | |
53 | { return *i; } | |
54 | }; | |
55 | #endif // wxUSE_UNICODE_WCHAR || !wxUSE_UNICODE | |
56 | ||
57 | ||
58 | #if wxUSE_UNICODE_UTF8 | |
59 | struct WXDLLIMPEXP_BASE wxStringOperationsUtf8 | |
60 | { | |
61 | // checks correctness of UTF-8 sequence | |
111d9948 VS |
62 | static bool IsValidUtf8String(const char *c, |
63 | size_t len = wxStringImpl::npos); | |
657a8a35 VZ |
64 | static bool IsValidUtf8LeadByte(unsigned char c) |
65 | { | |
66 | return (c <= 0x7F) || (c >= 0xC2 && c <= 0xF4); | |
67 | } | |
467175ab VS |
68 | |
69 | // table of offsets to skip forward when iterating over UTF-8 sequence | |
1774c3c5 | 70 | static const unsigned char ms_utf8IterTable[256]; |
467175ab VS |
71 | |
72 | ||
73 | template<typename Iterator> | |
74 | static void IncIter(Iterator& i) | |
75 | { | |
76 | wxASSERT( IsValidUtf8LeadByte(*i) ); | |
77 | i += ms_utf8IterTable[(unsigned char)*i]; | |
78 | } | |
79 | ||
80 | template<typename Iterator> | |
81 | static void DecIter(Iterator& i) | |
82 | { | |
83 | wxASSERT( IsValidUtf8LeadByte(*i) ); | |
84 | ||
85 | // Non-lead bytes are all in the 0x80..0xBF range (i.e. 10xxxxxx in | |
86 | // binary), so we just have to go back until we hit a byte that is | |
87 | // either < 0x80 (i.e. 0xxxxxxx in binary) or 0xC0..0xFF (11xxxxxx in | |
88 | // binary; this includes some invalid values, but we can ignore it | |
89 | // here, because we assume valid UTF-8 input for the purpose of | |
90 | // efficient implementation). | |
91 | --i; | |
92 | while ( ((*i) & 0xC0) == 0x80 /* 2 highest bits are '10' */ ) | |
93 | --i; | |
94 | } | |
95 | ||
96 | template<typename Iterator> | |
b5343e06 | 97 | static Iterator AddToIter(const Iterator& i, ptrdiff_t n) |
467175ab VS |
98 | { |
99 | Iterator out(i); | |
100 | ||
101 | if ( n > 0 ) | |
102 | { | |
b5343e06 | 103 | for ( ptrdiff_t j = 0; j < n; ++j ) |
467175ab VS |
104 | IncIter(out); |
105 | } | |
106 | else if ( n < 0 ) | |
107 | { | |
b5343e06 | 108 | for ( ptrdiff_t j = 0; j > n; --j ) |
467175ab VS |
109 | DecIter(out); |
110 | } | |
111 | ||
112 | return out; | |
113 | } | |
114 | ||
115 | template<typename Iterator> | |
b5343e06 | 116 | static ptrdiff_t DiffIters(Iterator i1, Iterator i2) |
467175ab | 117 | { |
b5343e06 | 118 | ptrdiff_t dist = 0; |
467175ab VS |
119 | |
120 | if ( i1 < i2 ) | |
121 | { | |
122 | while ( i1 != i2 ) | |
123 | { | |
124 | IncIter(i1); | |
125 | dist--; | |
126 | } | |
127 | } | |
128 | else if ( i2 < i1 ) | |
129 | { | |
130 | while ( i2 != i1 ) | |
131 | { | |
132 | IncIter(i2); | |
133 | dist++; | |
134 | } | |
135 | } | |
136 | ||
137 | return dist; | |
138 | } | |
139 | ||
467175ab | 140 | // encodes the character as UTF-8: |
1fc10687 VS |
141 | typedef wxUniChar::Utf8CharBuffer Utf8CharBuffer; |
142 | static Utf8CharBuffer EncodeChar(const wxUniChar& ch) | |
143 | { return ch.AsUTF8(); } | |
467175ab VS |
144 | |
145 | // returns n copies of ch encoded in UTF-8 string | |
146 | static wxCharBuffer EncodeNChars(size_t n, const wxUniChar& ch); | |
147 | ||
148 | // returns the length of UTF-8 encoding of the character with lead byte 'c' | |
149 | static size_t GetUtf8CharLength(char c) | |
150 | { | |
151 | wxASSERT( IsValidUtf8LeadByte(c) ); | |
152 | return ms_utf8IterTable[(unsigned char)c]; | |
153 | } | |
154 | ||
155 | // decodes single UTF-8 character from UTF-8 string | |
ac2d749e VS |
156 | static wxUniChar DecodeChar(wxStringImpl::const_iterator i) |
157 | { | |
158 | if ( (unsigned char)*i < 0x80 ) | |
159 | return (int)*i; | |
160 | return DecodeNonAsciiChar(i); | |
161 | } | |
162 | ||
163 | private: | |
164 | static wxUniChar DecodeNonAsciiChar(wxStringImpl::const_iterator i); | |
467175ab VS |
165 | }; |
166 | #endif // wxUSE_UNICODE_UTF8 | |
167 | ||
168 | ||
169 | #if wxUSE_UNICODE_UTF8 | |
170 | typedef wxStringOperationsUtf8 wxStringOperations; | |
171 | #else | |
172 | typedef wxStringOperationsWchar wxStringOperations; | |
173 | #endif | |
174 | ||
175 | #endif // _WX_WXSTRINGOPS_H_ |