kicad/include/utf8.h

221 lines
6.4 KiB
C++

#ifndef UTF8_H_
#define UTF8_H_
/*
* This program source code file is part of KiCad, a free EDA CAD application.
*
* Copyright (C) 2013 SoftPLC Corporation, Dick Hollenbeck <dick@softplc.com>
* Copyright (C) 2013 KiCad Developers, see CHANGELOG.TXT for contributors.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, you may find one here:
* http://www.gnu.org/licenses/old-licenses/gpl-2.0.html
* or you may search the http://www.gnu.org website for the version 2 license,
* or you may write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA
*/
#include <string>
#include <wx/string.h>
/**
* Class UTF8
* is an 8 bit std::string that is assuredly encoded in UTF8, and supplies special
* conversion support to and from wxString, and has iteration over unicode characters.
*
* <p>I've been careful to supply only conversion facilities and not try
* and duplicate wxString() with many member functions. In the end it is
* to be a std::string. There are multiple ways to create text into a std::string
* without the need of too many member functions:
*
* <ul>
* <li>richio.h's StrPrintf()</li>
* <li>std::ostringstream.</li>
* </ul>
*
* <p>Because this class used no virtuals, it should be possible to cast any
* std::string into a UTF8 using this kind of cast: (UTF8 &) without construction
* or copying being the effect of the cast. Be sure the source std::string holds
* UTF8 encoded text before you do that.
*
* @author Dick Hollenbeck
*/
class UTF8 : public std::string
{
public:
UTF8( const wxString& o );
/// This is the only constructor for which you could end up with
/// non-UTF8 encoding, but that would be your fault.
UTF8( const char* txt ) :
std::string( txt )
{
}
/// For use with _() function on wx 2.8:
UTF8( const wchar_t* txt );
UTF8( const std::string& o ) :
std::string( o )
{
}
UTF8() :
std::string()
{
}
UTF8& operator=( const wxString& o );
UTF8& operator=( const std::string& o )
{
std::string::operator=( o );
return *this;
}
UTF8& operator=( const char* s )
{
std::string::operator=( s );
return *this;
}
UTF8& operator=( char c )
{
std::string::operator=( c );
return *this;
}
UTF8 substr( size_t pos = 0, size_t len = npos ) const
{
return std::string::substr( pos, len );
}
operator wxString () const;
/// This one is not in std::string, and one wonders why... might be a solid
/// enough reason to remove it still.
operator char* () const
{
return (char*) c_str();
}
/**
* Function uni_forward
* advances over a single UTF8 encoded multibyte character, capturing the
* unicode character as it goes, and returning the number of bytes consumed.
*
* @param aSequence is the UTF8 byte sequence, must be aligned on start of character.
* @param aResult is where to put the unicode character, and may be NULL if no interest.
* @return int - the count of bytes consumed.
*/
static int uni_forward( const unsigned char* aSequence, unsigned* aResult = NULL );
/**
* class uni_iter
* is a non-muting iterator that walks through unicode code points in the UTF8 encoded
* string. The normal ++(), ++(int), ->(), and *() operators are all supported
* for read only access and they return an unsigned holding the unicode character
* appropriate for the respective operator.
*/
class uni_iter
{
friend class UTF8;
const unsigned char* it;
// private constructor.
uni_iter( const char* start ) :
it( (const unsigned char*) start )
{
// for the human: assert( sizeof(unsigned) >= 4 );
}
public:
uni_iter( const uni_iter& o )
{
it = o.it;
}
/// pre-increment and return uni_iter at new position
const uni_iter& operator++()
{
it += uni_forward( it );
return *this;
}
/// post-increment and return uni_iter at initial position
uni_iter operator++( int )
{
uni_iter ret = *this;
it += uni_forward( it );
return ret;
}
/*
/// return unicode at current position
unsigned operator->() const
{
unsigned result;
// grab the result, do not advance
uni_forward( it, &result );
return result;
}
*/
/// return unicode at current position
unsigned operator*() const
{
unsigned result;
// grab the result, do not advance
uni_forward( it, &result );
return result;
}
bool operator==( const uni_iter& other ) const { return it == other.it; }
bool operator!=( const uni_iter& other ) const { return it != other.it; }
/// Since the ++ operators advance more than one byte, this is your best
/// loop termination test, < end(), not == end().
bool operator< ( const uni_iter& other ) const { return it < other.it; }
bool operator<=( const uni_iter& other ) const { return it <= other.it; }
bool operator> ( const uni_iter& other ) const { return it > other.it; }
bool operator>=( const uni_iter& other ) const { return it >= other.it; }
};
/**
* Function ubegin
* returns a @a uni_iter initialized to the start of "this" UTF8 byte sequence.
*/
uni_iter ubegin() const
{
return uni_iter( data() );
}
/**
* Function uend
* returns a @a uni_iter initialized to the end of "this" UTF8 byte sequence.
*/
uni_iter uend() const
{
return uni_iter( data() + size() );
}
};
#endif // UTF8_H__