/* utf.js - UTF-8 <=> UTF-16 convertion
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*
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* Copyright (C) 1999 Masanao Izumo <iz@onicos.co.jp>
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* Version: 1.0
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* LastModified: Dec 25 1999
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* This library is free. You can redistribute it and/or modify it.
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*/
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/*
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* Interfaces:
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* utf8 = utf16to8(utf16);
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* utf16 = utf16to8(utf8);
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*/
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function utf16to8(str) {
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var out, i, len, c;
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out = "";
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len = str.length;
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for(i = 0; i < len; i++) {
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c = str.charCodeAt(i);
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if ((c >= 0x0001) && (c <= 0x007F)) {
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out += str.charAt(i);
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} else if (c > 0x07FF) {
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out += String.fromCharCode(0xE0 | ((c >> 12) & 0x0F));
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out += String.fromCharCode(0x80 | ((c >> 6) & 0x3F));
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out += String.fromCharCode(0x80 | ((c >> 0) & 0x3F));
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} else {
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out += String.fromCharCode(0xC0 | ((c >> 6) & 0x1F));
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out += String.fromCharCode(0x80 | ((c >> 0) & 0x3F));
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}
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}
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return out;
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}
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function utf8to16(str) {
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var out, i, len, c;
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var char2, char3;
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out = "";
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len = str.length;
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i = 0;
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while(i < len) {
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c = str.charCodeAt(i++);
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switch(c >> 4)
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{
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case 0: case 1: case 2: case 3: case 4: case 5: case 6: case 7:
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// 0xxxxxxx
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out += str.charAt(i-1);
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break;
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case 12: case 13:
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// 110x xxxx 10xx xxxx
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char2 = str.charCodeAt(i++);
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out += String.fromCharCode(((c & 0x1F) << 6) | (char2 & 0x3F));
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break;
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case 14:
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// 1110 xxxx 10xx xxxx 10xx xxxx
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char2 = str.charCodeAt(i++);
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char3 = str.charCodeAt(i++);
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out += String.fromCharCode(((c & 0x0F) << 12) |
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((char2 & 0x3F) << 6) |
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((char3 & 0x3F) << 0));
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break;
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}
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}
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return out;
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}
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