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-rw-r--r--middleware/node_modules/iconv-lite/encodings/utf16.js177
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diff --git a/middleware/node_modules/iconv-lite/encodings/utf16.js b/middleware/node_modules/iconv-lite/encodings/utf16.js
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+++ b/middleware/node_modules/iconv-lite/encodings/utf16.js
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+"use strict";
+var Buffer = require("safer-buffer").Buffer;
+
+// Note: UTF16-LE (or UCS2) codec is Node.js native. See encodings/internal.js
+
+// == UTF16-BE codec. ==========================================================
+
+exports.utf16be = Utf16BECodec;
+function Utf16BECodec() {
+}
+
+Utf16BECodec.prototype.encoder = Utf16BEEncoder;
+Utf16BECodec.prototype.decoder = Utf16BEDecoder;
+Utf16BECodec.prototype.bomAware = true;
+
+
+// -- Encoding
+
+function Utf16BEEncoder() {
+}
+
+Utf16BEEncoder.prototype.write = function(str) {
+ var buf = Buffer.from(str, 'ucs2');
+ for (var i = 0; i < buf.length; i += 2) {
+ var tmp = buf[i]; buf[i] = buf[i+1]; buf[i+1] = tmp;
+ }
+ return buf;
+}
+
+Utf16BEEncoder.prototype.end = function() {
+}
+
+
+// -- Decoding
+
+function Utf16BEDecoder() {
+ this.overflowByte = -1;
+}
+
+Utf16BEDecoder.prototype.write = function(buf) {
+ if (buf.length == 0)
+ return '';
+
+ var buf2 = Buffer.alloc(buf.length + 1),
+ i = 0, j = 0;
+
+ if (this.overflowByte !== -1) {
+ buf2[0] = buf[0];
+ buf2[1] = this.overflowByte;
+ i = 1; j = 2;
+ }
+
+ for (; i < buf.length-1; i += 2, j+= 2) {
+ buf2[j] = buf[i+1];
+ buf2[j+1] = buf[i];
+ }
+
+ this.overflowByte = (i == buf.length-1) ? buf[buf.length-1] : -1;
+
+ return buf2.slice(0, j).toString('ucs2');
+}
+
+Utf16BEDecoder.prototype.end = function() {
+}
+
+
+// == UTF-16 codec =============================================================
+// Decoder chooses automatically from UTF-16LE and UTF-16BE using BOM and space-based heuristic.
+// Defaults to UTF-16LE, as it's prevalent and default in Node.
+// http://en.wikipedia.org/wiki/UTF-16 and http://encoding.spec.whatwg.org/#utf-16le
+// Decoder default can be changed: iconv.decode(buf, 'utf16', {defaultEncoding: 'utf-16be'});
+
+// Encoder uses UTF-16LE and prepends BOM (which can be overridden with addBOM: false).
+
+exports.utf16 = Utf16Codec;
+function Utf16Codec(codecOptions, iconv) {
+ this.iconv = iconv;
+}
+
+Utf16Codec.prototype.encoder = Utf16Encoder;
+Utf16Codec.prototype.decoder = Utf16Decoder;
+
+
+// -- Encoding (pass-through)
+
+function Utf16Encoder(options, codec) {
+ options = options || {};
+ if (options.addBOM === undefined)
+ options.addBOM = true;
+ this.encoder = codec.iconv.getEncoder('utf-16le', options);
+}
+
+Utf16Encoder.prototype.write = function(str) {
+ return this.encoder.write(str);
+}
+
+Utf16Encoder.prototype.end = function() {
+ return this.encoder.end();
+}
+
+
+// -- Decoding
+
+function Utf16Decoder(options, codec) {
+ this.decoder = null;
+ this.initialBytes = [];
+ this.initialBytesLen = 0;
+
+ this.options = options || {};
+ this.iconv = codec.iconv;
+}
+
+Utf16Decoder.prototype.write = function(buf) {
+ if (!this.decoder) {
+ // Codec is not chosen yet. Accumulate initial bytes.
+ this.initialBytes.push(buf);
+ this.initialBytesLen += buf.length;
+
+ if (this.initialBytesLen < 16) // We need more bytes to use space heuristic (see below)
+ return '';
+
+ // We have enough bytes -> detect endianness.
+ var buf = Buffer.concat(this.initialBytes),
+ encoding = detectEncoding(buf, this.options.defaultEncoding);
+ this.decoder = this.iconv.getDecoder(encoding, this.options);
+ this.initialBytes.length = this.initialBytesLen = 0;
+ }
+
+ return this.decoder.write(buf);
+}
+
+Utf16Decoder.prototype.end = function() {
+ if (!this.decoder) {
+ var buf = Buffer.concat(this.initialBytes),
+ encoding = detectEncoding(buf, this.options.defaultEncoding);
+ this.decoder = this.iconv.getDecoder(encoding, this.options);
+
+ var res = this.decoder.write(buf),
+ trail = this.decoder.end();
+
+ return trail ? (res + trail) : res;
+ }
+ return this.decoder.end();
+}
+
+function detectEncoding(buf, defaultEncoding) {
+ var enc = defaultEncoding || 'utf-16le';
+
+ if (buf.length >= 2) {
+ // Check BOM.
+ if (buf[0] == 0xFE && buf[1] == 0xFF) // UTF-16BE BOM
+ enc = 'utf-16be';
+ else if (buf[0] == 0xFF && buf[1] == 0xFE) // UTF-16LE BOM
+ enc = 'utf-16le';
+ else {
+ // No BOM found. Try to deduce encoding from initial content.
+ // Most of the time, the content has ASCII chars (U+00**), but the opposite (U+**00) is uncommon.
+ // So, we count ASCII as if it was LE or BE, and decide from that.
+ var asciiCharsLE = 0, asciiCharsBE = 0, // Counts of chars in both positions
+ _len = Math.min(buf.length - (buf.length % 2), 64); // Len is always even.
+
+ for (var i = 0; i < _len; i += 2) {
+ if (buf[i] === 0 && buf[i+1] !== 0) asciiCharsBE++;
+ if (buf[i] !== 0 && buf[i+1] === 0) asciiCharsLE++;
+ }
+
+ if (asciiCharsBE > asciiCharsLE)
+ enc = 'utf-16be';
+ else if (asciiCharsBE < asciiCharsLE)
+ enc = 'utf-16le';
+ }
+ }
+
+ return enc;
+}
+
+