+// this table gives the length of the UTF-8 encoding from its first character:
+const unsigned char tableUtf8Lengths[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:
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, // 80..8F
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, // 90..9F
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, // A0..AF
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, // B0..BF
+ 0, 0, // 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):
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 // F5..FF
+};
+
+size_t
+wxMBConvStrictUTF8::ToWChar(wchar_t *dst, size_t dstLen,
+ const char *src, size_t srcLen) const
+{
+ wchar_t *out = dstLen ? dst : NULL;
+ size_t written = 0;
+
+ if ( srcLen == wxNO_LEN )
+ srcLen = strlen(src) + 1;
+
+ for ( const char *p = src; ; p++ )
+ {
+ if ( !(srcLen == wxNO_LEN ? *p : srcLen) )
+ {
+ // all done successfully, just add the trailing NULL if we are not
+ // using explicit length
+ if ( srcLen == wxNO_LEN )
+ {
+ if ( out )
+ {
+ if ( !dstLen )
+ break;
+
+ *out = L'\0';
+ }
+
+ written++;
+ }
+
+ return written;
+ }
+
+ unsigned char c = *p;
+ unsigned len = tableUtf8Lengths[c];
+ if ( !len )
+ break;
+
+ if ( srcLen < len ) // the test works for wxNO_LEN too
+ break;
+
+ if ( srcLen != wxNO_LEN )
+ srcLen -= len;
+
+ if ( out && !dstLen-- )
+ break;
+
+
+ // 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 length:
+ static const unsigned char leadValueMask[] = { 0x7F, 0x1F, 0x0F, 0x07 };
+
+ // mask and value of lead byte's most significant bits, by length:
+ static const unsigned char leadMarkerMask[] = { 0x80, 0xE0, 0xF0, 0xF8 };
+ static const unsigned char leadMarkerVal[] = { 0x00, 0xC0, 0xE0, 0xF0 };
+
+ len--; // it's more convenient to work with 0-based length here
+
+ // extract the lead byte's value bits:
+ if ( (c & leadMarkerMask[len]) != leadMarkerVal[len] )
+ break;
+
+ wxUint32 code = c & leadValueMask[len];
+
+ // all remaining bytes, if any, are handled in the same way regardless of
+ // sequence's length:
+ for ( ; len; --len )
+ {
+ c = *++p;
+ if ( (c & 0xC0) != 0x80 )
+ return wxCONV_FAILED;
+
+ code <<= 6;
+ code |= c & 0x3F;
+ }
+
+#ifdef WC_UTF16
+ // cast is ok because wchar_t == wxUint16 if WC_UTF16
+ if ( encode_utf16(code, (wxUint16 *)out) == 2 )
+ {
+ if ( out )
+ out++;
+ written++;
+ }
+#else // !WC_UTF16
+ if ( out )
+ *out = code;
+#endif // WC_UTF16/!WC_UTF16
+
+ if ( out )
+ out++;
+
+ written++;
+ }
+
+ return wxCONV_FAILED;
+}
+
+size_t
+wxMBConvStrictUTF8::FromWChar(char *dst, size_t dstLen,
+ const wchar_t *src, size_t srcLen) const
+{
+ char *out = dstLen ? dst : NULL;
+ size_t written = 0;
+
+ for ( const wchar_t *wp = src; ; wp++ )
+ {
+ if ( !(srcLen == wxNO_LEN ? *wp : srcLen--) )
+ {
+ // all done successfully, just add the trailing NULL if we are not
+ // using explicit length
+ if ( srcLen == wxNO_LEN )
+ {
+ if ( out )
+ {
+ if ( !dstLen )
+ break;
+
+ *out = '\0';
+ }
+
+ written++;
+ }
+
+ return written;
+ }
+
+
+ wxUint32 code;
+#ifdef WC_UTF16
+ // cast is ok for WC_UTF16
+ if ( decode_utf16((const wxUint16 *)wp, code) == 2 )
+ {
+ // skip the next char too as we decoded a surrogate
+ wp++;
+ }
+#else // wchar_t is UTF-32
+ code = *wp & 0x7fffffff;
+#endif
+
+ unsigned len;
+ if ( code <= 0x7F )
+ {
+ len = 1;
+ if ( out )
+ {
+ if ( dstLen < len )
+ break;
+
+ out[0] = (char)code;
+ }
+ }
+ else if ( code <= 0x07FF )
+ {
+ len = 2;
+ if ( out )
+ {
+ if ( dstLen < len )
+ break;
+
+ // 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 )
+ {
+ len = 3;
+ if ( out )
+ {
+ if ( dstLen < len )
+ break;
+
+ out[2] = 0x80 | (code & 0x3F); code >>= 6;
+ out[1] = 0x80 | (code & 0x3F); code >>= 6;
+ out[0] = 0xE0 | code;
+ }
+ }
+ else if ( code <= 0x10FFFF )
+ {
+ len = 4;
+ if ( out )
+ {
+ if ( dstLen < len )
+ break;
+
+ 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") );
+ break;
+ }
+
+ if ( out )
+ {
+ out += len;
+ dstLen -= len;
+ }
+
+ written += len;
+ }
+
+ // we only get here if an error occurs during decoding
+ return wxCONV_FAILED;
+}
+