brush_cli/node_modules/zip-stream/lib/util/DeflateRawChecksum.js

A tool for creating and developing cmos PC Framework project.

/**
 * node-zip-stream
 *
 * Copyright (c) 2014 Chris Talkington, contributors.
 * Licensed under the MIT license.
 * https://github.com/ctalkington/node-zip-stream/blob/master/LICENSE-MIT
 */
var zlib = require('zlib');
var inherits = require('util').inherits;

var util = require('./');

function DeflateRawChecksum(options) {
  zlib.DeflateRaw.call(this, options);

  this.checksum = util.crc32();
  this.digest = null;

  this.rawSize = 0;
  this.compressedSize = 0;

  this.on('data', function(chunk) {
    this.compressedSize += chunk.length;
  });

  this.once('end', function() {
    this.digest = this.checksum.digest();
  });
}

inherits(DeflateRawChecksum, zlib.DeflateRaw);

DeflateRawChecksum.prototype.write = function(chunk, cb) {
  if (chunk) {
    this.checksum.update(chunk);
    this.rawSize += chunk.length;
  }

  return zlib.DeflateRaw.prototype.write.call(this, chunk, cb);
};

module.exports = DeflateRawChecksum;