-// ---------------------------------------------------------------------------
-// UTF-8 operations
-// ---------------------------------------------------------------------------
-
-//
-// Table 3.1B from Unicode spec: Legal UTF-8 Byte Sequences
-//
-// Code Points | 1st Byte | 2nd Byte | 3rd Byte | 4th Byte |
-// -------------------+----------+----------+----------+----------+
-// U+0000..U+007F | 00..7F | | | |
-// U+0080..U+07FF | C2..DF | 80..BF | | |
-// U+0800..U+0FFF | E0 | A0..BF | 80..BF | |
-// U+1000..U+FFFF | E1..EF | 80..BF | 80..BF | |
-// U+10000..U+3FFFF | F0 | 90..BF | 80..BF | 80..BF |
-// U+40000..U+FFFFF | F1..F3 | 80..BF | 80..BF | 80..BF |
-// U+100000..U+10FFFF | F4 | 80..8F | 80..BF | 80..BF |
-// -------------------+----------+----------+----------+----------+
-
-bool wxString::IsValidUtf8String(const char *str)
-{
- if ( !str )
- return true; // empty string is UTF8 string
-
- const unsigned char *c = (const unsigned char*)str;
-
- for ( ; *c; ++c )
- {
- unsigned char b = *c;
-
- if ( b <= 0x7F ) // 00..7F
- continue;
-
- else if ( b < 0xC2 ) // invalid lead bytes: 80..C1
- return false;
-
- // two-byte sequences:
- else if ( b <= 0xDF ) // C2..DF
- {
- b = *(++c);
- if ( !(b >= 0x80 && b <= 0xBF ) )
- return false;
- }
-
- // three-byte sequences:
- else if ( b == 0xE0 )
- {
- b = *(++c);
- if ( !(b >= 0xA0 && b <= 0xBF ) )
- return false;
- b = *(++c);
- if ( !(b >= 0x80 && b <= 0xBF ) )
- return false;
- }
- else if ( b <= 0xEF ) // E1..EF
- {
- for ( int i = 0; i < 2; ++i )
- {
- b = *(++c);
- if ( !(b >= 0x80 && b <= 0xBF ) )
- return false;
- }
- }
-
- // four-byte sequences:
- else if ( b == 0xF0 )
- {
- b = *(++c);
- if ( !(b >= 0x90 && b <= 0xBF ) )
- return false;
- for ( int i = 0; i < 2; ++i )
- {
- b = *(++c);
- if ( !(b >= 0x80 && b <= 0xBF ) )
- return false;
- }
- }
- else if ( b <= 0xF3 ) // F1..F3
- {
- for ( int i = 0; i < 3; ++i )
- {
- b = *(++c);
- if ( !(b >= 0x80 && b <= 0xBF ) )
- return false;
- }
- }
- else if ( b == 0xF4 )
- {
- b = *(++c);
- if ( !(b >= 0x80 && b <= 0x8F ) )
- return false;
- for ( int i = 0; i < 2; ++i )
- {
- b = *(++c);
- if ( !(b >= 0x80 && b <= 0xBF ) )
- return false;
- }
- }
- else // otherwise, it's invalid lead byte
- return false;
- }
-
- return true;
-}
-
-#ifdef __WXDEBUG__
-/* static */
-bool wxString::IsValidUtf8LeadByte(unsigned char c)
-{
- return (c <= 0x7F) || (c >= 0xC2 && c <= 0xF4);
-}
-#endif
-
-unsigned char wxString::ms_utf8IterTable[256] = {
- // single-byte sequences (ASCII):
- 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, // 00..0F
- 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, // 10..1F
- 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, // 20..2F
- 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, // 30..3F
- 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, // 40..4F
- 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, // 50..5F
- 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, // 60..6F
- 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, // 70..7F
-
- // these are invalid, we use step 1 to skip
- // over them (should never happen):
- 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, // 80..8F
- 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, // 90..9F
- 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, // A0..AF
- 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, // B0..BF
- 1, 1, // C0,C1
-
- // two-byte sequences:
- 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, // C2..CF
- 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, // D0..DF
-
- // three-byte sequences:
- 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, // E0..EF
-
- // four-byte sequences:
- 4, 4, 4, 4, 4, // F0..F4
-
- // these are invalid again (5- or 6-byte
- // sequences and sequences for code points
- // above U+10FFFF, as restricted by RFC 3629):
- 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1 // F5..FF
-};
-
-/* static */
-void wxString::DecIter(wxStringImpl::const_iterator& i)
-{
- wxASSERT( IsValidUtf8LeadByte(*i) );
-
- // Non-lead bytes are all in the 0x80..0xBF range (i.e. 10xxxxxx in
- // binary), so we just have to go back until we hit a byte that is either
- // < 0x80 (i.e. 0xxxxxxx in binary) or 0xC0..0xFF (11xxxxxx in binary; this
- // includes some invalid values, but we can ignore it here, because we
- // assume valid UTF-8 input for the purpose of efficient implementation).
- --i;
- while ( ((*i) & 0xC0) == 0x80 /* 2 highest bits are '10' */ )
- --i;
-}
-
-/* static */
-void wxString::DecIter(wxStringImpl::iterator& i)
-{
- // FIXME-UTF8: use template instead
- wxASSERT( IsValidUtf8LeadByte(*i) );
- --i;
- while ( ((*i) & 0xC0) == 0x80 /* 2 highest bits are '10' */ )
- --i;
-}
-
-/* static */
-wxStringImpl::const_iterator
-wxString::AddToIter(wxStringImpl::const_iterator i, int n)
-{
- wxStringImpl::const_iterator out(i);
-
- if ( n > 0 )
- {
- for ( int j = 0; j < n; ++j )
- IncIter(out);
- }
- else if ( n < 0 )
- {
- for ( int j = 0; j > n; --j )
- DecIter(out);
- }
-
- return out;
-}
-
-wxStringImpl::iterator
-wxString::AddToIter(wxStringImpl::iterator i, int n)
-{
- // FIXME-UTF8: use template instead
- wxStringImpl::iterator out(i);
-
- if ( n > 0 )
- {
- for ( int j = 0; j < n; ++j )
- IncIter(out);
- }
- else if ( n < 0 )
- {
- for ( int j = 0; j > n; --j )
- DecIter(out);
- }
-
- return out;
-}
-
-
-/* static */
-int wxString::DiffIters(wxStringImpl::const_iterator i1,
- wxStringImpl::const_iterator i2)
-{
- int dist = 0;
-
- if ( i1 < i2 )
- {
- while ( i1 != i2 )
- {
- IncIter(i1);
- dist--;
- }
- }
- else if ( i2 < i1 )
- {
- while ( i2 != i1 )
- {
- IncIter(i2);
- dist++;
- }
- }
-
- return dist;
-}
-
-int wxString::DiffIters(wxStringImpl::iterator i1, wxStringImpl::iterator i2)
-{
- // FIXME-UTF8: use template instead
- int dist = 0;
-
- if ( i1 < i2 )
- {
- while ( i1 != i2 )
- {
- IncIter(i1);
- dist--;
- }
- }
- else if ( i2 < i1 )
- {
- while ( i2 != i1 )
- {
- IncIter(i2);
- dist++;
- }
- }
-
- return dist;
-}
-
-/* static */
-wxString::Utf8CharBuffer wxString::EncodeChar(wxUniChar ch)
-{
- Utf8CharBuffer buf;
- char *out = buf.data;
-
- wxUniChar::value_type code = ch.GetValue();
-
- // Char. number range | UTF-8 octet sequence
- // (hexadecimal) | (binary)
- // ----------------------+---------------------------------------------
- // 0000 0000 - 0000 007F | 0xxxxxxx
- // 0000 0080 - 0000 07FF | 110xxxxx 10xxxxxx
- // 0000 0800 - 0000 FFFF | 1110xxxx 10xxxxxx 10xxxxxx
- // 0001 0000 - 0010 FFFF | 11110xxx 10xxxxxx 10xxxxxx 10xxxxxx
- //
- // Code point value is stored in bits marked with 'x', lowest-order bit
- // of the value on the right side in the diagram above.
- // (from RFC 3629)
-
- if ( code <= 0x7F )
- {
- out[1] = 0;
- out[0] = (char)code;
- }
- else if ( code <= 0x07FF )
- {
- out[2] = 0;
- // NB: this line takes 6 least significant bits, encodes them as
- // 10xxxxxx and discards them so that the next byte can be encoded:
- out[1] = 0x80 | (code & 0x3F); code >>= 6;
- out[0] = 0xC0 | code;
- }
- else if ( code < 0xFFFF )
- {
- out[3] = 0;
- out[2] = 0x80 | (code & 0x3F); code >>= 6;
- out[1] = 0x80 | (code & 0x3F); code >>= 6;
- out[0] = 0xE0 | code;
- }
- else if ( code <= 0x10FFFF )
- {
- out[4] = 0;
- out[3] = 0x80 | (code & 0x3F); code >>= 6;
- out[2] = 0x80 | (code & 0x3F); code >>= 6;
- out[1] = 0x80 | (code & 0x3F); code >>= 6;
- out[0] = 0xF0 | code;
- }
- else
- {
- wxFAIL_MSG( _T("trying to encode undefined Unicode character") );
- out[0] = 0;
- }
-
- return buf;
-}
-
-/* static */
-wxUniChar wxUniCharRef::DecodeChar(wxStringImpl::const_iterator i)
-{
- wxASSERT( wxString::IsValidUtf8LeadByte(*i) ); // FIXME-UTF8: no "wxString::"
-
- wxUniChar::value_type code = 0;
- size_t len = wxString::GetUtf8CharLength(*i);
- wxASSERT_MSG( len <= 4, _T("invalid UTF-8 sequence length") );
-
- // Char. number range | UTF-8 octet sequence
- // (hexadecimal) | (binary)
- // ----------------------+---------------------------------------------
- // 0000 0000 - 0000 007F | 0xxxxxxx
- // 0000 0080 - 0000 07FF | 110xxxxx 10xxxxxx
- // 0000 0800 - 0000 FFFF | 1110xxxx 10xxxxxx 10xxxxxx
- // 0001 0000 - 0010 FFFF | 11110xxx 10xxxxxx 10xxxxxx 10xxxxxx
- //
- // Code point value is stored in bits marked with 'x', lowest-order bit
- // of the value on the right side in the diagram above.
- // (from RFC 3629)
-
- // mask to extract lead byte's value ('x' bits above), by sequence's length:
- static const unsigned char s_leadValueMask[4] = { 0x7F, 0x1F, 0x0F, 0x07 };
-#ifdef __WXDEBUG__
- // mask and value of lead byte's most significant bits, by length:
- static const unsigned char s_leadMarkerMask[4] = { 0x80, 0xE0, 0xF0, 0xF8 };
- static const unsigned char s_leadMarkerVal[4] = { 0x00, 0xC0, 0xE0, 0xF0 };
-#endif
-
- // extract the lead byte's value bits:
- wxASSERT_MSG( ((unsigned char)*i & s_leadMarkerMask[len-1]) ==
- s_leadMarkerVal[len-1],
- _T("invalid UTF-8 lead byte") );
- code = (unsigned char)*i & s_leadValueMask[len-1];
-
- // all remaining bytes, if any, are handled in the same way regardless of
- // sequence's length:
- for ( ++i ; len > 1; --len, ++i )
- {
- wxASSERT_MSG( ((unsigned char)*i & 0xC0) == 0x80,
- _T("invalid UTF-8 byte") );
-
- code <<= 6;
- code |= (unsigned char)*i & 0x3F;
- }
-
- return wxUniChar(code);
-}
-
-/* static */
-wxCharBuffer wxString::EncodeNChars(size_t n, wxUniChar ch)
-{
- Utf8CharBuffer once(EncodeChar(ch));
- // the IncIter() table can be used to determine the length of ch's encoding:
- size_t len = ms_utf8IterTable[(unsigned char)once.data[0]];
-
- wxCharBuffer buf(n * len);
- char *ptr = buf.data();
- for ( size_t i = 0; i < n; i++, ptr += len )
- {
- memcpy(ptr, once.data, len);
- }
-
- return buf;
-}
-
-
projects / wxWidgets.git / commitdiff
