1 | 'use strict';
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2 |
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3 | var Buffer = require('safer-buffer').Buffer;
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4 |
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5 |
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6 |
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7 | exports._utf32 = Utf32Codec;
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8 |
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9 | function Utf32Codec(codecOptions, iconv) {
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10 | this.iconv = iconv;
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11 | this.bomAware = true;
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12 | this.isLE = codecOptions.isLE;
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13 | }
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14 |
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15 | exports.utf32le = { type: '_utf32', isLE: true };
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16 | exports.utf32be = { type: '_utf32', isLE: false };
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17 |
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18 |
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19 | exports.ucs4le = 'utf32le';
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20 | exports.ucs4be = 'utf32be';
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21 |
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22 | Utf32Codec.prototype.encoder = Utf32Encoder;
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23 | Utf32Codec.prototype.decoder = Utf32Decoder;
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24 |
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25 |
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26 |
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27 | function Utf32Encoder(options, codec) {
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28 | this.isLE = codec.isLE;
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29 | this.highSurrogate = 0;
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30 | }
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31 |
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32 | Utf32Encoder.prototype.write = function(str) {
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33 | var src = Buffer.from(str, 'ucs2');
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34 | var dst = Buffer.alloc(src.length * 2);
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35 | var write32 = this.isLE ? dst.writeUInt32LE : dst.writeUInt32BE;
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36 | var offset = 0;
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37 |
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38 | for (var i = 0; i < src.length; i += 2) {
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39 | var code = src.readUInt16LE(i);
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40 | var isHighSurrogate = (0xD800 <= code && code < 0xDC00);
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41 | var isLowSurrogate = (0xDC00 <= code && code < 0xE000);
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42 |
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43 | if (this.highSurrogate) {
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44 | if (isHighSurrogate || !isLowSurrogate) {
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45 |
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46 |
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47 |
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48 | write32.call(dst, this.highSurrogate, offset);
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49 | offset += 4;
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50 | }
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51 | else {
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52 |
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53 | var codepoint = (((this.highSurrogate - 0xD800) << 10) | (code - 0xDC00)) + 0x10000;
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54 |
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55 | write32.call(dst, codepoint, offset);
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56 | offset += 4;
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57 | this.highSurrogate = 0;
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58 |
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59 | continue;
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60 | }
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61 | }
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62 |
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63 | if (isHighSurrogate)
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64 | this.highSurrogate = code;
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65 | else {
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66 |
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67 |
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68 |
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69 | write32.call(dst, code, offset);
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70 | offset += 4;
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71 | this.highSurrogate = 0;
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72 | }
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73 | }
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74 |
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75 | if (offset < dst.length)
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76 | dst = dst.slice(0, offset);
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77 |
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78 | return dst;
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79 | };
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80 |
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81 | Utf32Encoder.prototype.end = function() {
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82 |
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83 | if (!this.highSurrogate)
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84 | return;
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85 |
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86 | var buf = Buffer.alloc(4);
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87 |
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88 | if (this.isLE)
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89 | buf.writeUInt32LE(this.highSurrogate, 0);
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90 | else
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91 | buf.writeUInt32BE(this.highSurrogate, 0);
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92 |
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93 | this.highSurrogate = 0;
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94 |
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95 | return buf;
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96 | };
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97 |
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98 |
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99 |
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100 | function Utf32Decoder(options, codec) {
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101 | this.isLE = codec.isLE;
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102 | this.badChar = codec.iconv.defaultCharUnicode.charCodeAt(0);
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103 | this.overflow = [];
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104 | }
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105 |
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106 | Utf32Decoder.prototype.write = function(src) {
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107 | if (src.length === 0)
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108 | return '';
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109 |
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110 | var i = 0;
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111 | var codepoint = 0;
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112 | var dst = Buffer.alloc(src.length + 4);
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113 | var offset = 0;
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114 | var isLE = this.isLE;
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115 | var overflow = this.overflow;
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116 | var badChar = this.badChar;
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117 |
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118 | if (overflow.length > 0) {
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119 | for (; i < src.length && overflow.length < 4; i++)
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120 | overflow.push(src[i]);
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121 |
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122 | if (overflow.length === 4) {
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123 |
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124 |
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125 | if (isLE) {
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126 | codepoint = overflow[i] | (overflow[i+1] << 8) | (overflow[i+2] << 16) | (overflow[i+3] << 24);
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127 | } else {
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128 | codepoint = overflow[i+3] | (overflow[i+2] << 8) | (overflow[i+1] << 16) | (overflow[i] << 24);
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129 | }
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130 | overflow.length = 0;
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131 |
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132 | offset = _writeCodepoint(dst, offset, codepoint, badChar);
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133 | }
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134 | }
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135 |
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136 |
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137 | for (; i < src.length - 3; i += 4) {
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138 |
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139 | if (isLE) {
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140 | codepoint = src[i] | (src[i+1] << 8) | (src[i+2] << 16) | (src[i+3] << 24);
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141 | } else {
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142 | codepoint = src[i+3] | (src[i+2] << 8) | (src[i+1] << 16) | (src[i] << 24);
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143 | }
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144 | offset = _writeCodepoint(dst, offset, codepoint, badChar);
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145 | }
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146 |
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147 |
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148 | for (; i < src.length; i++) {
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149 | overflow.push(src[i]);
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150 | }
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151 |
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152 | return dst.slice(0, offset).toString('ucs2');
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153 | };
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154 |
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155 | function _writeCodepoint(dst, offset, codepoint, badChar) {
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156 |
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157 | if (codepoint < 0 || codepoint > 0x10FFFF) {
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158 |
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159 | codepoint = badChar;
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160 | }
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161 |
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162 |
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163 | if (codepoint >= 0x10000) {
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164 | codepoint -= 0x10000;
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165 |
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166 | var high = 0xD800 | (codepoint >> 10);
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167 | dst[offset++] = high & 0xff;
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168 | dst[offset++] = high >> 8;
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169 |
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170 |
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171 | var codepoint = 0xDC00 | (codepoint & 0x3FF);
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172 | }
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173 |
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174 |
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175 | dst[offset++] = codepoint & 0xff;
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176 | dst[offset++] = codepoint >> 8;
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177 |
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178 | return offset;
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179 | };
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180 |
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181 | Utf32Decoder.prototype.end = function() {
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182 | this.overflow.length = 0;
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183 | };
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184 |
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185 |
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186 |
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187 |
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188 |
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189 |
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190 |
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191 |
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192 | exports.utf32 = Utf32AutoCodec;
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193 | exports.ucs4 = 'utf32';
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194 |
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195 | function Utf32AutoCodec(options, iconv) {
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196 | this.iconv = iconv;
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197 | }
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198 |
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199 | Utf32AutoCodec.prototype.encoder = Utf32AutoEncoder;
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200 | Utf32AutoCodec.prototype.decoder = Utf32AutoDecoder;
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201 |
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202 |
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203 |
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204 | function Utf32AutoEncoder(options, codec) {
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205 | options = options || {};
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206 |
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207 | if (options.addBOM === undefined)
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208 | options.addBOM = true;
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209 |
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210 | this.encoder = codec.iconv.getEncoder(options.defaultEncoding || 'utf-32le', options);
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211 | }
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212 |
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213 | Utf32AutoEncoder.prototype.write = function(str) {
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214 | return this.encoder.write(str);
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215 | };
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216 |
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217 | Utf32AutoEncoder.prototype.end = function() {
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218 | return this.encoder.end();
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219 | };
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220 |
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221 |
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222 |
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223 | function Utf32AutoDecoder(options, codec) {
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224 | this.decoder = null;
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225 | this.initialBufs = [];
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226 | this.initialBufsLen = 0;
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227 | this.options = options || {};
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228 | this.iconv = codec.iconv;
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229 | }
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230 |
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231 | Utf32AutoDecoder.prototype.write = function(buf) {
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232 | if (!this.decoder) {
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233 |
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234 | this.initialBufs.push(buf);
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235 | this.initialBufsLen += buf.length;
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236 |
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237 | if (this.initialBufsLen < 32)
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238 | return '';
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239 |
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240 |
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241 | var encoding = detectEncoding(this.initialBufs, this.options.defaultEncoding);
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242 | this.decoder = this.iconv.getDecoder(encoding, this.options);
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243 |
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244 | var resStr = '';
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245 | for (var i = 0; i < this.initialBufs.length; i++)
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246 | resStr += this.decoder.write(this.initialBufs[i]);
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247 |
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248 | this.initialBufs.length = this.initialBufsLen = 0;
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249 | return resStr;
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250 | }
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251 |
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252 | return this.decoder.write(buf);
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253 | };
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254 |
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255 | Utf32AutoDecoder.prototype.end = function() {
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256 | if (!this.decoder) {
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257 | var encoding = detectEncoding(this.initialBufs, this.options.defaultEncoding);
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258 | this.decoder = this.iconv.getDecoder(encoding, this.options);
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259 |
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260 | var resStr = '';
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261 | for (var i = 0; i < this.initialBufs.length; i++)
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262 | resStr += this.decoder.write(this.initialBufs[i]);
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263 |
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264 | var trail = this.decoder.end();
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265 | if (trail)
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266 | resStr += trail;
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267 |
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268 | this.initialBufs.length = this.initialBufsLen = 0;
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269 | return resStr;
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270 | }
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271 |
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272 | return this.decoder.end();
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273 | };
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274 |
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275 | function detectEncoding(bufs, defaultEncoding) {
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276 | var b = [];
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277 | var charsProcessed = 0;
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278 | var invalidLE = 0, invalidBE = 0;
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279 | var bmpCharsLE = 0, bmpCharsBE = 0;
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280 |
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281 | outer_loop:
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282 | for (var i = 0; i < bufs.length; i++) {
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283 | var buf = bufs[i];
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284 | for (var j = 0; j < buf.length; j++) {
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285 | b.push(buf[j]);
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286 | if (b.length === 4) {
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287 | if (charsProcessed === 0) {
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288 |
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289 | if (b[0] === 0xFF && b[1] === 0xFE && b[2] === 0 && b[3] === 0) {
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290 | return 'utf-32le';
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291 | }
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292 | if (b[0] === 0 && b[1] === 0 && b[2] === 0xFE && b[3] === 0xFF) {
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293 | return 'utf-32be';
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294 | }
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295 | }
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296 |
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297 | if (b[0] !== 0 || b[1] > 0x10) invalidBE++;
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298 | if (b[3] !== 0 || b[2] > 0x10) invalidLE++;
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299 |
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300 | if (b[0] === 0 && b[1] === 0 && (b[2] !== 0 || b[3] !== 0)) bmpCharsBE++;
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301 | if ((b[0] !== 0 || b[1] !== 0) && b[2] === 0 && b[3] === 0) bmpCharsLE++;
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302 |
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303 | b.length = 0;
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304 | charsProcessed++;
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305 |
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306 | if (charsProcessed >= 100) {
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307 | break outer_loop;
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308 | }
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309 | }
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310 | }
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311 | }
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312 |
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313 |
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314 | if (bmpCharsBE - invalidBE > bmpCharsLE - invalidLE) return 'utf-32be';
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315 | if (bmpCharsBE - invalidBE < bmpCharsLE - invalidLE) return 'utf-32le';
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316 |
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317 |
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318 | return defaultEncoding || 'utf-32le';
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319 | }
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