dolphin/Externals/wxWidgets3/src/common/stringops.cpp

316 lines
10 KiB
C++

/////////////////////////////////////////////////////////////////////////////
// Name: src/common/stringops.cpp
// Purpose: implementation of wxString primitive operations
// Author: Vaclav Slavik
// Modified by:
// Created: 2007-04-16
// Copyright: (c) 2007 REA Elektronik GmbH
// Licence: wxWindows licence
/////////////////////////////////////////////////////////////////////////////
// ===========================================================================
// headers
// ===========================================================================
// For compilers that support precompilation, includes "wx.h".
#include "wx/wxprec.h"
#ifdef __BORLANDC__
#pragma hdrstop
#endif
#ifndef WX_PRECOMP
#include "wx/stringops.h"
#endif
// ===========================================================================
// implementation
// ===========================================================================
#if wxUSE_UNICODE_UTF8
// ---------------------------------------------------------------------------
// UTF-8 sequences lengths
// ---------------------------------------------------------------------------
const unsigned char wxStringOperationsUtf8::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
};
// ---------------------------------------------------------------------------
// 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 wxStringOperationsUtf8::IsValidUtf8String(const char *str, size_t len)
{
if ( !str )
return true; // empty string is UTF8 string
const unsigned char *c = (const unsigned char*)str;
const unsigned char * const end = (len == wxStringImpl::npos) ? NULL : c + len;
for ( ; c != end && *c; ++c )
{
unsigned char b = *c;
if ( end != NULL )
{
// if the string is not NULL-terminated, verify we have enough
// bytes in it left for current character's encoding:
if ( c + ms_utf8IterTable[*c] > end )
return false;
}
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 == 0xED )
{
b = *(++c);
if ( !(b >= 0x80 && b <= 0x9F ) )
return false;
b = *(++c);
if ( !(b >= 0x80 && b <= 0xBF ) )
return false;
}
else if ( b <= 0xEF ) // E1..EC EE..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;
}
// NB: this is in this file and not unichar.cpp to keep all UTF-8 encoding
// code in single place
wxUniChar::Utf8CharBuffer wxUniChar::AsUTF8() const
{
Utf8CharBuffer buf = { "" }; // init to avoid g++ 4.1 warning with -O2
char *out = buf.data;
value_type code = 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( wxT("trying to encode undefined Unicode character") );
out[0] = 0;
}
return buf;
}
wxUniChar
wxStringOperationsUtf8::DecodeNonAsciiChar(wxStringImpl::const_iterator i)
{
wxASSERT( IsValidUtf8LeadByte(*i) );
size_t len = GetUtf8CharLength(*i);
wxASSERT_MSG( len <= 4, wxT("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 };
#if wxDEBUG_LEVEL
// 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],
wxT("invalid UTF-8 lead byte") );
wxUniChar::value_type 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,
wxT("invalid UTF-8 byte") );
code <<= 6;
code |= (unsigned char)*i & 0x3F;
}
return wxUniChar(code);
}
wxCharBuffer wxStringOperationsUtf8::EncodeNChars(size_t n, const 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;
}
#endif // wxUSE_UNICODE_UTF8