initial commit

node_modules/hash-base/index.js

@@ -0,0 +1,138 @@
+'use strict'
+var Buffer = require('safe-buffer').Buffer
+var Transform = require('stream').Transform
+var inherits = require('inherits')
+
+function HashBase (blockSize) {
+  Transform.call(this)
+
+  this._block = Buffer.allocUnsafe(blockSize)
+  this._blockSize = blockSize
+  this._blockOffset = 0
+  this._length = [0, 0, 0, 0]
+
+  this._finalized = false
+}
+
+inherits(HashBase, Transform)
+
+HashBase.prototype._transform = function (chunk, encoding, callback) {
+  var error = null
+  try {
+    this.update(chunk, encoding)
+  } catch (err) {
+    error = err
+  }
+
+  callback(error)
+}
+
+HashBase.prototype._flush = function (callback) {
+  var error = null
+  try {
+    this.push(this.digest())
+  } catch (err) {
+    error = err
+  }
+
+  callback(error)
+}
+
+var useUint8Array = typeof Uint8Array !== 'undefined'
+var useArrayBuffer = typeof ArrayBuffer !== 'undefined' &&
+  typeof Uint8Array !== 'undefined' &&
+  ArrayBuffer.isView &&
+  (Buffer.prototype instanceof Uint8Array || Buffer.TYPED_ARRAY_SUPPORT)
+
+function toBuffer (data, encoding) {
+  // No need to do anything for exact instance
+  // This is only valid when safe-buffer.Buffer === buffer.Buffer, i.e. when Buffer.from/Buffer.alloc existed
+  if (data instanceof Buffer) return data
+
+  // Convert strings to Buffer
+  if (typeof data === 'string') return Buffer.from(data, encoding)
+
+  /*
+   * Wrap any TypedArray instances and DataViews
+   * Makes sense only on engines with full TypedArray support -- let Buffer detect that
+   */
+  if (useArrayBuffer && ArrayBuffer.isView(data)) {
+    if (data.byteLength === 0) return Buffer.alloc(0) // Bug in Node.js <6.3.1, which treats this as out-of-bounds
+    var res = Buffer.from(data.buffer, data.byteOffset, data.byteLength)
+    // Recheck result size, as offset/length doesn't work on Node.js <5.10
+    // We just go to Uint8Array case if this fails
+    if (res.byteLength === data.byteLength) return res
+  }
+
+  /*
+   * Uint8Array in engines where Buffer.from might not work with ArrayBuffer, just copy over
+   * Doesn't make sense with other TypedArray instances
+   */
+  if (useUint8Array && data instanceof Uint8Array) return Buffer.from(data)
+
+  /*
+   * Old Buffer polyfill on an engine that doesn't have TypedArray support
+   * Also, this is from a different Buffer polyfill implementation then we have, as instanceof check failed
+   * Convert to our current Buffer implementation
+   */
+  if (
+    Buffer.isBuffer(data) &&
+    data.constructor &&
+    typeof data.constructor.isBuffer === 'function' &&
+    data.constructor.isBuffer(data)
+  ) {
+    return Buffer.from(data)
+  }
+
+  throw new TypeError('The "data" argument must be of type string or an instance of Buffer, TypedArray, or DataView.')
+}
+
+HashBase.prototype.update = function (data, encoding) {
+  if (this._finalized) throw new Error('Digest already called')
+
+  data = toBuffer(data, encoding) // asserts correct input type
+
+  // consume data
+  var block = this._block
+  var offset = 0
+  while (this._blockOffset + data.length - offset >= this._blockSize) {
+    for (var i = this._blockOffset; i < this._blockSize;) block[i++] = data[offset++]
+    this._update()
+    this._blockOffset = 0
+  }
+  while (offset < data.length) block[this._blockOffset++] = data[offset++]
+
+  // update length
+  for (var j = 0, carry = data.length * 8; carry > 0; ++j) {
+    this._length[j] += carry
+    carry = (this._length[j] / 0x0100000000) | 0
+    if (carry > 0) this._length[j] -= 0x0100000000 * carry
+  }
+
+  return this
+}
+
+HashBase.prototype._update = function () {
+  throw new Error('_update is not implemented')
+}
+
+HashBase.prototype.digest = function (encoding) {
+  if (this._finalized) throw new Error('Digest already called')
+  this._finalized = true
+
+  var digest = this._digest()
+  if (encoding !== undefined) digest = digest.toString(encoding)
+
+  // reset state
+  this._block.fill(0)
+  this._blockOffset = 0
+  for (var i = 0; i < 4; ++i) this._length[i] = 0
+
+  return digest
+}
+
+HashBase.prototype._digest = function () {
+  throw new Error('_digest is not implemented')
+}
+
+module.exports = HashBase