Contents
Introduction
- utf8 을 다루는 코드를 소개 한다. iconv 같은 좋은 라이브러리도 있지만... utf8 만 다룰려고 라이브러리 쓰는 것은 배보다 배꼽이다. 다음은 웹서핑 하다가 얻어온 코드이다. perl 의 코드를 보고 cpp 로 컨버트 한것이라고 한다.
Detailed Description
ex 1
Usage
...
void CUtf8_sampleDlg::OnOK()
{
// TODO: Add extra validation here
char in_buf[MAX_PATH]={0,};
char out_buf[MAX_PATH]={0,};
// 유니코드 변환을 해보자.
FILE* fp = fopen("c:\\안녕.txt", "rb");
int insize = fread(in_buf, sizeof(char), sizeof(in_buf), fp);
int nResult = UTF8_Decode(in_buf, out_buf, insize);
fclose(fp);
CDialog::OnOK();
}
...
utf8.h
#if !defined(__UTF8_H__) #define __UTF8_H__ int utf8_encode_calcsize(unsigned short * in); int utf8_encode_calcsize(unsigned long c); int utf8_encode(unsigned short * in, unsigned char * out); int utf8_encode(unsigned long c, unsigned char * out); int utf8_decode_calcsize(unsigned char * in); int utf8_decode(unsigned char * in, unsigned short * out); int UTF8_Encode(LPCSTR lpszIn, LPSTR lpszOut, int nBufLen); int UTF8_Decode(LPCSTR lpszIn, LPSTR lpszOut, int nBufLen); #endif
utf8.cpp
#include "stdafx.h"
#include "utf8.h"
#ifdef _DEBUG
#define new DEBUG_NEW
#undef THIS_FILE
static char THIS_FILE[] = __FILE__;
#endif
int utf8_encode_calcsize(unsigned short * i)
{
int n = 0;
while( *i )
{
n += utf8_encode_calcsize(*i);
i += 1;
}
return n;
}
int utf8_encode_calcsize(unsigned long c)
{
if( c < 0x80 )
return 1;
if( c < 0x800 )
return 2;
if( c < 0x10000L )
return 3;
if( c < 0x200000L )
return 4;
if( c < 0x4000000L )
return 5;
return 6;
}
int utf8_encode(unsigned short * in, unsigned char * out)
{
int n = 0, m;
while( *in )
{
m = utf8_encode(*in, out);
out += m;
n += m;
in += 1;
}
*out = NULL;
return n;
}
#pragma warning(disable:4244)
int utf8_encode(unsigned long c, unsigned char * out)
{
if( c < 0x80 )
{
out[0] = c;
return 1;
}
if( c < 0x800 )
{
out[0] = (0xC0 | (c>>6 ) & 0x1F);
out[1] = (0x80 | (c ) & 0x3F);
return 2;
}
if( c < 0x10000L )
{
out[0] = (0xE0 | (c>>12) & 0xF );
out[1] = (0x80 | (c>>6 ) & 0x3F);
out[2] = (0x80 | (c ) & 0x3F);
return 3;
}
if( c < 0x200000L )
{
out[0] = (0xF0 | (c>>18) & 0x7 );
out[1] = (0x80 | (c>>12) & 0x3F);
out[2] = (0x80 | (c>>6 ) & 0x3F);
out[3] = (0x80 | (c ) & 0x3F);
return 4;
}
if( c < 0x4000000L )
{
out[0] = (0xF8 | (c>>24) & 0x3 );
out[1] = (0x80 | (c>>18) & 0x3F);
out[2] = (0x80 | (c>>12) & 0x3F);
out[3] = (0x80 | (c>>6 ) & 0x3F);
out[4] = (0x80 | (c ) & 0x3F);
return 5;
}
// else
{
out[0] = (0xFC | (c>>30) & 0x1 );
out[1] = (0x80 | (c>>24) & 0x3F);
out[2] = (0x80 | (c>>18) & 0x3F);
out[3] = (0x80 | (c>>12) & 0x3F);
out[4] = (0x80 | (c>>6 ) & 0x3F);
out[5] = (0x80 | (c ) & 0x3F);
return 6;
}
}
#pragma warning(default:4244)
int utf8_decode_calcsize(unsigned char * in)
{
int i = 0;
int n = 0;
for( i = 0; in[i] != NULL; i++ )
{
if( (in[i] & 0x80) == 0x00 )
{
if( in[i] == '%' )
n += 3;
else
n += 1;
}
else if( (in[i] & 0xE0) == 0xC0 )
n += 2;
else if( (in[i] & 0xF0) == 0xE0 )
n += 3;
else if( (in[i] & 0xF8) == 0xF0 )
n += 4;
else if( (in[i] & 0xFC) == 0xF8 )
n += 5;
else if( (in[i] & 0xFE) == 0xFC )
n += 6;
// else
// return 0;
else
n += 1;
}
return n;
}
int utf8_decode(unsigned char * in, unsigned short * out)
{
for( int i = 0, j = 0; in[i] != NULL; j++ )
{
if( (in[i] & 0x80) == 0x00 )
{
if( in[i] == '%' )
{
// ESCAPE
out[j] = 0x20;
i += 3;
}
else
{
// ASCII
out[j] = (in[i] & 0x7F);
i++;
}
}
else if( (in[i] & 0xE0) == 0xC0 )
{
out[j] = ((in[i ] & 0x1F) << 6 ) |
((in[i+1] & 0x3F) );
i += 2;
}
else if( (in[i] & 0xF0) == 0xE0 )
{
out[j] = ((in[i ] & 0x1F) << 12) |
((in[i+1] & 0x3F) << 6 ) |
((in[i+2] & 0x3F) );
i += 3;
}
else if( (in[i] & 0xF8) == 0xF0 )
{
out[j] = ((in[i ] & 0x1F) << 18) |
((in[i+1] & 0x3F) << 12) |
((in[i+2] & 0x3F) << 6 ) |
((in[i+3] & 0x3F) );
i += 4;
}
else if( (in[i] & 0xFC) == 0xF8 )
{
out[j] = ((in[i ] & 0x1F) << 24) |
((in[i+1] & 0x3F) << 18) |
((in[i+2] & 0x3F) << 12) |
((in[i+3] & 0x3F) << 6 ) |
((in[i+4] & 0x3F) );
i += 5;
}
else if( (in[i] & 0xFE) == 0xFC )
{
out[j] = ((in[i ] & 0x1F) << 30) |
((in[i+1] & 0x3F) << 24) |
((in[i+2] & 0x3F) << 18) |
((in[i+3] & 0x3F) << 12) |
((in[i+4] & 0x3F) << 6 ) |
((in[i+5] & 0x3F) );
i += 6;
}
else
{
// ERROR!!!
// just use bad character
out[j] = in[i++];
}
}
//
out[j] = NULL;
return j;
}
/////////////////////////////////////////////////////////////////////////////
//
int UTF8_Encode(LPCSTR lpszIn, LPSTR lpszOut, int nBufLen)
{
LPWSTR lpwzIn;
int nInBuf, nOutLen;
nInBuf = MultiByteToWideChar(CP_ACP, 0, lpszIn, -1, NULL, 0);
nOutLen = 0;
if( nInBuf > 0 )
{
if( (lpwzIn = new WCHAR[nInBuf + 1]) != NULL )
{
MultiByteToWideChar(CP_ACP, 0, lpszIn, -1, lpwzIn, nInBuf + 1);
if( (nOutLen = utf8_encode_calcsize(lpwzIn)) <= nBufLen )
{
if( lpszOut )
utf8_encode(lpwzIn, (unsigned char *)lpszOut);
}
delete[] lpwzIn;
}
}
return nOutLen;
}
int UTF8_Decode(LPCSTR lpszIn, LPSTR lpszOut, int nBufLen)
{
LPWSTR lpwzOut;
int nOutLen;
//
if( (nOutLen = utf8_decode_calcsize((unsigned char *)lpszIn)) > 0 )
{
if( (lpwzOut = new WCHAR[nOutLen + 1]) != NULL )
{
utf8_decode((unsigned char *)lpszIn, lpwzOut);
if( (nOutLen = WideCharToMultiByte(CP_ACP, 0, lpwzOut, -1, NULL, 0, NULL, NULL)) <= nBufLen && nOutLen > 0 )
{
if( lpszOut )
WideCharToMultiByte(CP_ACP, 0, lpwzOut, -1, lpszOut, nBufLen, NULL, NULL);
}
delete[] lpwzOut;
}
}
return nOutLen;
}
ex 2
utf8 을 전환해주는 코드
// Copyright (c) 2006 Nemanja Trifunovic
/*
Permission is hereby granted, free of charge, to any person or organization
obtaining a copy of the software and accompanying documentation covered by
this license (the "Software") to use, reproduce, display, distribute,
execute, and transmit the Software, and to prepare derivative works of the
Software, and to permit third-parties to whom the Software is furnished to
do so, all subject to the following:
The copyright notices in the Software and this entire statement, including
the above license grant, this restriction and the following disclaimer,
must be included in all copies of the Software, in whole or in part, and
all derivative works of the Software, unless such copies or derivative
works are solely in the form of machine-executable object code generated by
a source language processor.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE, TITLE AND NON-INFRINGEMENT. IN NO EVENT
SHALL THE COPYRIGHT HOLDERS OR ANYONE DISTRIBUTING THE SOFTWARE BE LIABLE
FOR ANY DAMAGES OR OTHER LIABILITY, WHETHER IN CONTRACT, TORT OR OTHERWISE,
ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
DEALINGS IN THE SOFTWARE.
*/
#ifndef UTF8_FOR_CPP_2675DCD0_9480_4c0c_B92A_CC14C027B731
#define UTF8_FOR_CPP_2675DCD0_9480_4c0c_B92A_CC14C027B731
#include <iterator>
#include <exception>
namespace utf8
{
// The typedefs for 8-bit, 16-bit and 32-bit unsigned integers
// You may need to change them to match your system.
// These typedefs have the same names as ones from cstdint, or boost/cstdint
typedef unsigned char uint8_t;
typedef unsigned short uint16_t;
typedef unsigned int uint32_t;
// Exceptions that may be thrown from the library functions.
class invalid_code_point : public std::exception {
uint32_t cp;
public:
invalid_code_point(uint32_t cp) : cp(cp) {}
const char* what() { return "Invalid code point"; }
uint32_t code_point() const {return cp;}
};
class invalid_utf8 : public std::exception {
uint8_t u8;
public:
invalid_utf8 (uint8_t u) : u8(u) {}
const char* what() { return "Invalid UTF-8"; }
uint8_t utf8_octet() const {return u8;}
};
class invalid_utf16 : public std::exception {
uint16_t u16;
public:
invalid_utf16 (uint16_t u) : u16(u) {}
const char* what() { return "Invalid UTF-16"; }
uint16_t utf16_word() const {return u16;}
};
class not_enough_room : public std::exception {
public:
const char* what() { return "Not enough space"; }
};
// Helper code - not intended to be directly called by the library users. May be changed at any time
namespace internal
{
// Unicode constants
// Leading (high) surrogates: 0xd800 - 0xdbff
// Trailing (low) surrogates: 0xdc00 - 0xdfff
const uint16_t LEAD_SURROGATE_MIN = 0xd800u;
const uint16_t LEAD_SURROGATE_MAX = 0xdbffu;
const uint16_t TRAIL_SURROGATE_MIN = 0xdc00u;
const uint16_t TRAIL_SURROGATE_MAX = 0xdfffu;
const uint16_t LEAD_OFFSET = LEAD_SURROGATE_MIN - (0x10000 >> 10);
const uint32_t SURROGATE_OFFSET = 0x10000u - (LEAD_SURROGATE_MIN << 10) - TRAIL_SURROGATE_MIN;
// Maximum valid value for a Unicode code point
const uint32_t CODE_POINT_MAX = 0x0010ffffu;
template<typename octet_type>
inline uint8_t mask8(octet_type oc)
{
return static_cast<uint8_t>(0xff & oc);
}
template<typename u16_type>
inline uint16_t mask16(u16_type oc)
{
return static_cast<uint16_t>(0xffff & oc);
}
template<typename octet_type>
inline bool is_trail(octet_type oc)
{
return ((mask8(oc) >> 6) == 0x2);
}
template <typename u16>
inline bool is_surrogate(u16 cp)
{
return (cp >= LEAD_SURROGATE_MIN && cp <= TRAIL_SURROGATE_MAX);
}
template <typename u32>
inline bool is_code_point_valid(u32 cp)
{
return (cp <= CODE_POINT_MAX && !is_surrogate(cp) && cp != 0xfffe && cp != 0xffff);
}
template <typename octet_iterator>
inline typename std::iterator_traits<octet_iterator>::difference_type
sequence_length(octet_iterator lead_it)
{
uint8_t lead = mask8(*lead_it);
if (lead < 0x80)
return 1;
else if ((lead >> 5) == 0x6)
return 2;
else if ((lead >> 4) == 0xe)
return 3;
else if ((lead >> 3) == 0x1e)
return 4;
else
return 0;
}
enum utf_error {OK, NOT_ENOUGH_ROOM, INVALID_LEAD, INCOMPLETE_SEQUENCE, OVERLONG_SEQUENCE, INVALID_CODE_POINT};
template <typename octet_iterator>
utf_error validate_next(octet_iterator& it, octet_iterator end, uint32_t* code_point = 0)
{
uint32_t cp = mask8(*it);
// Check the lead octet
typedef typename std::iterator_traits<octet_iterator>::difference_type octet_differece_type;
octet_differece_type length = sequence_length(it);
// "Shortcut" for ASCII characters
if (length == 1) {
if (end - it > 0) {
if (code_point)
*code_point = cp;
++it;
return OK;
}
else
return NOT_ENOUGH_ROOM;
}
// Do we have enough memory?
if (end - it < length)
return NOT_ENOUGH_ROOM;
// Check trail octets and calculate the code point
switch (length) {
case 0:
return INVALID_LEAD;
break;
case 2:
if (is_trail(*(++it))) {
cp = ((cp << 6) & 0x7ff) + ((*it) & 0x3f);
}
else {
--it;
return INCOMPLETE_SEQUENCE;
}
break;
case 3:
if (is_trail(*(++it))) {
cp = ((cp << 12) & 0xffff) + ((mask8(*it) << 6) & 0xfff);
if (is_trail(*(++it))) {
cp += (*it) & 0x3f;
}
else {
--it; --it;
return INCOMPLETE_SEQUENCE;
}
}
else {
--it;
return INCOMPLETE_SEQUENCE;
}
break;
case 4:
if (is_trail(*(++it))) {
cp = ((cp << 18) & 0x1fffff) + ((mask8(*it) << 12) & 0x3ffff);
if (is_trail(*(++it))) {
cp += (mask8(*it) << 6) & 0xfff;
if (is_trail(*(++it))) {
cp += (*it) & 0x3f;
}
else {
--it; --it; --it;
return INCOMPLETE_SEQUENCE;
}
}
else {
--it; --it;
return INCOMPLETE_SEQUENCE;
}
}
else {
--it;
return INCOMPLETE_SEQUENCE;
}
break;
}
// Is the code point valid?
if (!is_code_point_valid(cp)) {
for (octet_differece_type i = 0; i < length - 1; ++i)
--it;
return INVALID_CODE_POINT;
}
if (code_point)
*code_point = cp;
if (cp < 0x80) {
if (length != 1) {
for (octet_differece_type i = 0; i < length - 1; ++i)
--it;
return OVERLONG_SEQUENCE;
}
}
else if (cp < 0x800) {
if (length != 2) {
for (octet_differece_type i = 0; i < length - 1; ++i)
--it;
return OVERLONG_SEQUENCE;
}
}
else if (cp < 0x10000) {
if (length != 3) {
for (octet_differece_type i = 0; i < length - 1; ++i)
--it;
return OVERLONG_SEQUENCE;
}
}
++it;
return OK;
}
} // namespace internal
/// The library API - functions intended to be called by the users
// Byte order mark
const uint8_t bom[] = {0xef, 0xbb, 0xbf};
template <typename octet_iterator>
octet_iterator find_invalid(octet_iterator start, octet_iterator end)
{
octet_iterator result = start;
while (result != end) {
internal::utf_error err_code = internal::validate_next(result, end);
if (err_code != internal::OK)
return result;
}
return result;
}
template <typename octet_iterator>
bool is_valid(octet_iterator start, octet_iterator end)
{
return (find_invalid(start, end) == end);
}
template <typename octet_iterator>
bool is_bom (octet_iterator it)
{
return (
(internal::mask8(*it++)) == bom[0] &&
(internal::mask8(*it++)) == bom[1] &&
(internal::mask8(*it)) == bom[2]
);
}
template <typename octet_iterator>
octet_iterator append(uint32_t cp, octet_iterator result)
{
if (!internal::is_code_point_valid(cp))
throw invalid_code_point(cp);
if (cp < 0x80) // one octet
*(result++) = static_cast<uint8_t>(cp);
else if (cp < 0x800) { // two octets
*(result++) = static_cast<uint8_t>((cp >> 6) | 0xc0);
*(result++) = static_cast<uint8_t>((cp & 0x3f) | 0x80);
}
else if (cp < 0x10000) { // three octets
*(result++) = static_cast<uint8_t>((cp >> 12) | 0xe0);
*(result++) = static_cast<uint8_t>((cp >> 6) & 0x3f | 0x80);
*(result++) = static_cast<uint8_t>((cp & 0x3f) | 0x80);
}
else if (cp <= internal::CODE_POINT_MAX) { // four octets
*(result++) = static_cast<uint8_t>((cp >> 18) | 0xf0);
*(result++) = static_cast<uint8_t>((cp >> 12)& 0x3f | 0x80);
*(result++) = static_cast<uint8_t>((cp >> 6) & 0x3f | 0x80);
*(result++) = static_cast<uint8_t>((cp & 0x3f) | 0x80);
}
else
throw invalid_code_point(cp);
return result;
}
template <typename octet_iterator>
uint32_t next(octet_iterator& it, octet_iterator end)
{
uint32_t cp = 0;
internal::utf_error err_code = internal::validate_next(it, end, &cp);
switch (err_code) {
case internal::OK :
break;
case internal::NOT_ENOUGH_ROOM :
throw not_enough_room();
case internal::INVALID_LEAD :
case internal::INCOMPLETE_SEQUENCE :
case internal::OVERLONG_SEQUENCE :
throw invalid_utf8(*it);
case internal::INVALID_CODE_POINT :
throw invalid_code_point(cp);
}
return cp;
}
template <typename octet_iterator>
uint32_t previous(octet_iterator& it, octet_iterator pass_start)
{
octet_iterator end = it;
while (internal::is_trail(*(--it)))
if (it == pass_start)
throw invalid_utf8(*it); // error - no lead byte in the sequence
octet_iterator temp = it;
return next(temp, end);
}
template <typename octet_iterator, typename distance_type>
void advance (octet_iterator& it, distance_type n, octet_iterator end)
{
for (distance_type i = 0; i < n; ++i)
next(it, end);
}
template <typename octet_iterator>
typename std::iterator_traits<octet_iterator>::difference_type
distance (octet_iterator first, octet_iterator last)
{
typename std::iterator_traits<octet_iterator>::difference_type dist;
for (dist = 0; first < last; ++dist)
next(first, last);
return dist;
}
template <typename u16bit_iterator, typename octet_iterator>
octet_iterator utf16to8 (u16bit_iterator start, u16bit_iterator end, octet_iterator result)
{
while (start != end) {
uint32_t cp = internal::mask16(*start++);
// Take care of surrogate pairs first
if (internal::is_surrogate(cp)) {
if (start != end) {
uint32_t trail_surrogate = internal::mask16(*start++);
if (trail_surrogate >= internal::TRAIL_SURROGATE_MIN && trail_surrogate <= internal::TRAIL_SURROGATE_MAX)
cp = (cp << 10) + trail_surrogate + internal::SURROGATE_OFFSET;
else
throw invalid_utf16(static_cast<uint16_t>(trail_surrogate));
}
else
throw invalid_utf16(static_cast<uint16_t>(*start));
}
result = append(cp, result);
}
return result;
}
template <typename u16bit_iterator, typename octet_iterator>
u16bit_iterator utf8to16 (octet_iterator start, octet_iterator end, u16bit_iterator result)
{
while (start != end) {
uint32_t cp = next(start, end);
if (cp > 0xffff) { //make a surrogate pair
*result++ = static_cast<uint16_t>((cp >> 10) + internal::LEAD_OFFSET);
*result++ = static_cast<uint16_t>((cp & 0x3ff) + internal::TRAIL_SURROGATE_MIN);
}
else
*result++ = static_cast<uint16_t>(cp);
}
return result;
}
template <typename octet_iterator, typename u32bit_iterator>
octet_iterator utf32to8 (u32bit_iterator start, u32bit_iterator end, octet_iterator result)
{
while (start != end)
result = append(*(start++), result);
return result;
}
template <typename octet_iterator, typename u32bit_iterator>
u32bit_iterator utf8to32 (octet_iterator start, octet_iterator end, u32bit_iterator result)
{
while (start < end)
(*result++) = next(start, end);
return result;
}
namespace unchecked
{
template <typename octet_iterator>
octet_iterator append(uint32_t cp, octet_iterator result)
{
if (cp < 0x80) // one octet
*(result++) = static_cast<uint8_t>(cp);
else if (cp < 0x800) { // two octets
*(result++) = static_cast<uint8_t>((cp >> 6) | 0xc0);
*(result++) = static_cast<uint8_t>((cp & 0x3f) | 0x80);
}
else if (cp < 0x10000) { // three octets
*(result++) = static_cast<uint8_t>((cp >> 12) | 0xe0);
*(result++) = static_cast<uint8_t>((cp >> 6) & 0x3f | 0x80);
*(result++) = static_cast<uint8_t>((cp & 0x3f) | 0x80);
}
else { // four octets
*(result++) = static_cast<uint8_t>((cp >> 18) | 0xf0);
*(result++) = static_cast<uint8_t>((cp >> 12)& 0x3f | 0x80);
*(result++) = static_cast<uint8_t>((cp >> 6) & 0x3f | 0x80);
*(result++) = static_cast<uint8_t>((cp & 0x3f) | 0x80);
}
return result;
}
template <typename octet_iterator>
uint32_t next(octet_iterator& it)
{
uint32_t cp = internal::mask8(*it);
typename std::iterator_traits<octet_iterator>::difference_type length = utf8::internal::sequence_length(it);
switch (length) {
case 1:
break;
case 2:
it++;
cp = ((cp << 6) & 0x7ff) + ((*it) & 0x3f);
break;
case 3:
++it;
cp = ((cp << 12) & 0xffff) + ((internal::mask8(*it) << 6) & 0xfff);
++it;
cp += (*it) & 0x3f;
break;
case 4:
++it;
cp = ((cp << 18) & 0x1fffff) + ((internal::mask8(*it) << 12) & 0x3ffff);
++it;
cp += (internal::mask8(*it) << 6) & 0xfff;
++it;
cp += (*it) & 0x3f;
break;
}
++it;
return cp;
}
template <typename octet_iterator>
uint32_t previous(octet_iterator& it)
{
while (internal::is_trail(*(--it))) ;
octet_iterator temp = it;
return next(temp);
}
template <typename octet_iterator, typename distance_type>
void advance (octet_iterator& it, distance_type n)
{
for (distance_type i = 0; i < n; ++i)
next(it);
}
template <typename octet_iterator>
typename std::iterator_traits<octet_iterator>::difference_type
distance (octet_iterator first, octet_iterator last)
{
typename std::iterator_traits<octet_iterator>::difference_type dist;
for (dist = 0; first < last; ++dist)
next(first);
return dist;
}
template <typename u16bit_iterator, typename octet_iterator>
octet_iterator utf16to8 (u16bit_iterator start, u16bit_iterator end, octet_iterator result)
{
while (start != end) {
uint32_t cp = internal::mask16(*start++);
// Take care of surrogate pairs first
if (internal::is_surrogate(cp)) {
uint32_t trail_surrogate = internal::mask16(*start++);
cp = (cp << 10) + trail_surrogate + internal::SURROGATE_OFFSET;
}
result = append(cp, result);
}
return result;
}
template <typename u16bit_iterator, typename octet_iterator>
u16bit_iterator utf8to16 (octet_iterator start, octet_iterator end, u16bit_iterator result)
{
while (start != end) {
uint32_t cp = next(start);
if (cp > 0xffff) { //make a surrogate pair
*result++ = static_cast<uint16_t>((cp >> 10) + internal::LEAD_OFFSET);
*result++ = static_cast<uint16_t>((cp & 0x3ff) + internal::TRAIL_SURROGATE_MIN);
}
else
*result++ = static_cast<uint16_t>(cp);
}
return result;
}
template <typename octet_iterator, typename u32bit_iterator>
octet_iterator utf32to8 (u32bit_iterator start, u32bit_iterator end, octet_iterator result)
{
while (start != end)
result = append(*(start++), result);
return result;
}
template <typename octet_iterator, typename u32bit_iterator>
u32bit_iterator utf8to32 (octet_iterator start, octet_iterator end, u32bit_iterator result)
{
while (start < end)
(*result++) = next(start);
return result;
}
} // namespace utf8::unchecked
} // namespace utf8
#endif // header guard
usage of ex2
#include <fstream>
#include <iostream>
#include <string>
#include <vector>
using namespace std;
int main()
{
if (argc != 2) {
cout << "\nUsage: docsample filename\n";
return 0;
}
const char* test_file_path = argv[1];
// Open the test file (must be UTF-8 encoded)
ifstream fs8(test_file_path);
if (!fs8.is_open()) {
cout << "Could not open " << test_file_path << endl;
return 0;
}
// Read the first line of the file
unsigned line_count = 1;
string line;
if (!getline(fs8, line))
return 0;
// Look for utf-8 byte-order mark at the beginning
if (line.size() > 2) {
if (utf8::is_bom(line.c_str()))
cout << "There is a byte order mark at the beginning of the file\n";
}
// Play with all the lines in the file
do {
// check for invalid utf-8 (for a simple yes/no check, there is also utf8::is_valid function)
string::iterator end_it = utf8::find_invalid(line.begin(), line.end());
if (end_it != line.end()) {
cout << "Invalid UTF-8 encoding detected at line " << line_count << "\n";
cout << "This part is fine: " << string(line.begin(), end_it) << "\n";
}
// Get the line length (at least for the valid part)
int length = utf8::distance(line.begin(), end_it);
cout << "Length of line " << line_count << " is " << length << "\n";
// Convert it to utf-16
vector<unsigned short> utf16line;
utf8::utf8to16(line.begin(), end_it, back_inserter(utf16line));
// And back to utf-8;
string utf8line;
utf8::utf16to8(utf16line.begin(), utf16line.end(), back_inserter(utf8line));
// Confirm that the conversion went OK:
if (utf8line != string(line.begin(), end_it))
cout << "Error in UTF-16 conversion at line: " << line_count << "\n";
getline(fs8, line);
line_count++;
} while (!fs8.eof());
return 0;
}
Reference
CategoryCPP CategoryUnicode
검색어: utf8