AK-21/Graphite-Industrial-Intelligence

1"use strict"2var Buffer = require("safer-buffer").Buffer3 4// UTF-7 codec, according to https://tools.ietf.org/html/rfc21525// See also below a UTF-7-IMAP codec, according to http://tools.ietf.org/html/rfc3501#section-5.1.36 7exports.utf7 = Utf7Codec8exports.unicode11utf7 = "utf7" // Alias UNICODE-1-1-UTF-79function Utf7Codec (codecOptions, iconv) {10  this.iconv = iconv11};12 13Utf7Codec.prototype.encoder = Utf7Encoder14Utf7Codec.prototype.decoder = Utf7Decoder15Utf7Codec.prototype.bomAware = true16 17// -- Encoding18 19// Why scape ()?./?20// eslint-disable-next-line no-useless-escape21var nonDirectChars = /[^A-Za-z0-9'\(\),-\.\/:\? \n\r\t]+/g22 23function Utf7Encoder (options, codec) {24  this.iconv = codec.iconv25}26 27Utf7Encoder.prototype.write = function (str) {28  // Naive implementation.29  // Non-direct chars are encoded as "+<base64>-"; single "+" char is encoded as "+-".30  return Buffer.from(str.replace(nonDirectChars, function (chunk) {31    return "+" + (chunk === "+"32      ? ""33      : this.iconv.encode(chunk, "utf16-be").toString("base64").replace(/=+$/, "")) +34            "-"35  }.bind(this)))36}37 38Utf7Encoder.prototype.end = function () {39}40 41// -- Decoding42 43function Utf7Decoder (options, codec) {44  this.iconv = codec.iconv45  this.inBase64 = false46  this.base64Accum = ""47}48 49// Why scape /?50// eslint-disable-next-line no-useless-escape51var base64Regex = /[A-Za-z0-9\/+]/52var base64Chars = []53for (var i = 0; i < 256; i++) { base64Chars[i] = base64Regex.test(String.fromCharCode(i)) }54 55var plusChar = "+".charCodeAt(0)56var minusChar = "-".charCodeAt(0)57var andChar = "&".charCodeAt(0)58 59Utf7Decoder.prototype.write = function (buf) {60  var res = ""; var lastI = 061  var inBase64 = this.inBase6462  var base64Accum = this.base64Accum63 64  // The decoder is more involved as we must handle chunks in stream.65 66  for (var i = 0; i < buf.length; i++) {67    if (!inBase64) { // We're in direct mode.68      // Write direct chars until '+'69      if (buf[i] == plusChar) {70        res += this.iconv.decode(buf.slice(lastI, i), "ascii") // Write direct chars.71        lastI = i + 172        inBase64 = true73      }74    } else { // We decode base64.75      if (!base64Chars[buf[i]]) { // Base64 ended.76        if (i == lastI && buf[i] == minusChar) { // "+-" -> "+"77          res += "+"78        } else {79          var b64str = base64Accum + this.iconv.decode(buf.slice(lastI, i), "ascii")80          res += this.iconv.decode(Buffer.from(b64str, "base64"), "utf16-be")81        }82 83        if (buf[i] != minusChar) // Minus is absorbed after base64.84        { i-- }85 86        lastI = i + 187        inBase64 = false88        base64Accum = ""89      }90    }91  }92 93  if (!inBase64) {94    res += this.iconv.decode(buf.slice(lastI), "ascii") // Write direct chars.95  } else {96    var b64str = base64Accum + this.iconv.decode(buf.slice(lastI), "ascii")97 98    var canBeDecoded = b64str.length - (b64str.length % 8) // Minimal chunk: 2 quads -> 2x3 bytes -> 3 chars.99    base64Accum = b64str.slice(canBeDecoded) // The rest will be decoded in future.100    b64str = b64str.slice(0, canBeDecoded)101 102    res += this.iconv.decode(Buffer.from(b64str, "base64"), "utf16-be")103  }104 105  this.inBase64 = inBase64106  this.base64Accum = base64Accum107 108  return res109}110 111Utf7Decoder.prototype.end = function () {112  var res = ""113  if (this.inBase64 && this.base64Accum.length > 0) { res = this.iconv.decode(Buffer.from(this.base64Accum, "base64"), "utf16-be") }114 115  this.inBase64 = false116  this.base64Accum = ""117  return res118}119 120// UTF-7-IMAP codec.121// RFC3501 Sec. 5.1.3 Modified UTF-7 (http://tools.ietf.org/html/rfc3501#section-5.1.3)122// Differences:123//  * Base64 part is started by "&" instead of "+"124//  * Direct characters are 0x20-0x7E, except "&" (0x26)125//  * In Base64, "," is used instead of "/"126//  * Base64 must not be used to represent direct characters.127//  * No implicit shift back from Base64 (should always end with '-')128//  * String must end in non-shifted position.129//  * "-&" while in base64 is not allowed.130 131exports.utf7imap = Utf7IMAPCodec132function Utf7IMAPCodec (codecOptions, iconv) {133  this.iconv = iconv134};135 136Utf7IMAPCodec.prototype.encoder = Utf7IMAPEncoder137Utf7IMAPCodec.prototype.decoder = Utf7IMAPDecoder138Utf7IMAPCodec.prototype.bomAware = true139 140// -- Encoding141 142function Utf7IMAPEncoder (options, codec) {143  this.iconv = codec.iconv144  this.inBase64 = false145  this.base64Accum = Buffer.alloc(6)146  this.base64AccumIdx = 0147}148 149Utf7IMAPEncoder.prototype.write = function (str) {150  var inBase64 = this.inBase64151  var base64Accum = this.base64Accum152  var base64AccumIdx = this.base64AccumIdx153  var buf = Buffer.alloc(str.length * 5 + 10); var bufIdx = 0154 155  for (var i = 0; i < str.length; i++) {156    var uChar = str.charCodeAt(i)157    if (uChar >= 0x20 && uChar <= 0x7E) { // Direct character or '&'.158      if (inBase64) {159        if (base64AccumIdx > 0) {160          bufIdx += buf.write(base64Accum.slice(0, base64AccumIdx).toString("base64").replace(/\//g, ",").replace(/=+$/, ""), bufIdx)161          base64AccumIdx = 0162        }163 164        buf[bufIdx++] = minusChar // Write '-', then go to direct mode.165        inBase64 = false166      }167 168      if (!inBase64) {169        buf[bufIdx++] = uChar // Write direct character170 171        if (uChar === andChar)  // Ampersand -> '&-'172        { buf[bufIdx++] = minusChar }173      }174    } else { // Non-direct character175      if (!inBase64) {176        buf[bufIdx++] = andChar // Write '&', then go to base64 mode.177        inBase64 = true178      }179      if (inBase64) {180        base64Accum[base64AccumIdx++] = uChar >> 8181        base64Accum[base64AccumIdx++] = uChar & 0xFF182 183        if (base64AccumIdx == base64Accum.length) {184          bufIdx += buf.write(base64Accum.toString("base64").replace(/\//g, ","), bufIdx)185          base64AccumIdx = 0186        }187      }188    }189  }190 191  this.inBase64 = inBase64192  this.base64AccumIdx = base64AccumIdx193 194  return buf.slice(0, bufIdx)195}196 197Utf7IMAPEncoder.prototype.end = function () {198  var buf = Buffer.alloc(10); var bufIdx = 0199  if (this.inBase64) {200    if (this.base64AccumIdx > 0) {201      bufIdx += buf.write(this.base64Accum.slice(0, this.base64AccumIdx).toString("base64").replace(/\//g, ",").replace(/=+$/, ""), bufIdx)202      this.base64AccumIdx = 0203    }204 205    buf[bufIdx++] = minusChar // Write '-', then go to direct mode.206    this.inBase64 = false207  }208 209  return buf.slice(0, bufIdx)210}211 212// -- Decoding213 214function Utf7IMAPDecoder (options, codec) {215  this.iconv = codec.iconv216  this.inBase64 = false217  this.base64Accum = ""218}219 220var base64IMAPChars = base64Chars.slice()221base64IMAPChars[",".charCodeAt(0)] = true222 223Utf7IMAPDecoder.prototype.write = function (buf) {224  var res = ""; var lastI = 0225  var inBase64 = this.inBase64226  var base64Accum = this.base64Accum227 228  // The decoder is more involved as we must handle chunks in stream.229  // It is forgiving, closer to standard UTF-7 (for example, '-' is optional at the end).230 231  for (var i = 0; i < buf.length; i++) {232    if (!inBase64) { // We're in direct mode.233      // Write direct chars until '&'234      if (buf[i] == andChar) {235        res += this.iconv.decode(buf.slice(lastI, i), "ascii") // Write direct chars.236        lastI = i + 1237        inBase64 = true238      }239    } else { // We decode base64.240      if (!base64IMAPChars[buf[i]]) { // Base64 ended.241        if (i == lastI && buf[i] == minusChar) { // "&-" -> "&"242          res += "&"243        } else {244          var b64str = base64Accum + this.iconv.decode(buf.slice(lastI, i), "ascii").replace(/,/g, "/")245          res += this.iconv.decode(Buffer.from(b64str, "base64"), "utf16-be")246        }247 248        if (buf[i] != minusChar) // Minus may be absorbed after base64.249        { i-- }250 251        lastI = i + 1252        inBase64 = false253        base64Accum = ""254      }255    }256  }257 258  if (!inBase64) {259    res += this.iconv.decode(buf.slice(lastI), "ascii") // Write direct chars.260  } else {261    var b64str = base64Accum + this.iconv.decode(buf.slice(lastI), "ascii").replace(/,/g, "/")262 263    var canBeDecoded = b64str.length - (b64str.length % 8) // Minimal chunk: 2 quads -> 2x3 bytes -> 3 chars.264    base64Accum = b64str.slice(canBeDecoded) // The rest will be decoded in future.265    b64str = b64str.slice(0, canBeDecoded)266 267    res += this.iconv.decode(Buffer.from(b64str, "base64"), "utf16-be")268  }269 270  this.inBase64 = inBase64271  this.base64Accum = base64Accum272 273  return res274}275 276Utf7IMAPDecoder.prototype.end = function () {277  var res = ""278  if (this.inBase64 && this.base64Accum.length > 0) { res = this.iconv.decode(Buffer.from(this.base64Accum, "base64"), "utf16-be") }279 280  this.inBase64 = false281  this.base64Accum = ""282  return res283}284