gb2312_to_unicode.cpp

SDL_Draw chinese test

#include "gb2312_to_Unicode.h"

int myUTF8_to_UNICODE(Uint16* unicode, unsigned char* utf8, int len);

std::vector<Uint16> getUnicode(const std::string& str)
{
	const int CHAR_SIZE = 256;
	//GB2312 src
	const unsigned char* src = (const unsigned char*)(str.c_str());
	size_t src_len = strlen((char*)src);
	//Unicode dst to get
	unsigned char dst[CHAR_SIZE] = {0};
    size_t dst_len = sizeof(dst);
	//iconv arg
	const unsigned char* in = src;
    unsigned char* out = dst;

	iconv_t cd;
	//GB2312 to UTF-8
    cd = iconv_open("UTF-8", "GB2312");
    if ((iconv_t)-1 == cd){
		exit (-1);
    }
	//conversion
    iconv(cd, (const char**)&in, &src_len, (char**)&out, &dst_len);

	//UTF-8 to Unicode
	int utf8Len = strlen((char*)dst);
	Uint16 unicodeData[CHAR_SIZE] = {0};
	int unicodeLen = myUTF8_to_UNICODE(unicodeData, dst, utf8Len);
	std::vector<Uint16> unicodeVectorArray;
	for (int i = 0; i < unicodeLen; i++) {
		unicodeVectorArray.push_back(unicodeData[i]);
	}
	
	iconv_close(cd); 
	return unicodeVectorArray;
}

int myUTF8_to_UNICODE(Uint16* unicode, unsigned char* utf8, int len)
{
	int length;
	unsigned char* t = utf8;

	length = 0;
	while (utf8 - t < len){
		//one byte.ASCII as a, b, c, 1, 2, 3... ect
		if ( *(unsigned char *) utf8 <= 0x7f ) {
			//expand with 0s.
			*unicode++ = *utf8++;
		}
		//2 byte.
		else if ( *(unsigned char *) utf8 <= 0xdf ) {
			*unicode++ = ((*(unsigned char *) utf8 & 0x1f) << 6) + ((*(unsigned char *) (utf8 + 1)) & 0x3f);
			utf8 += 2;
		}
		//3 byte.Chinese may use 3 byte.
		else {
			*unicode++ = ((int) (*(unsigned char *) utf8 & 0x0f) << 12) +
				((*(unsigned char *) (utf8 + 1) & 0x3f) << 6) +
				(*(unsigned char *) (utf8 + 2) & 0x3f);
			utf8 += 3;
		}
		length++;
	}

	*unicode = 0;
	
	return (length);
}