dns2/lib/writer.js

A DNS Server and Client Implementation in Pure JavaScript with no dependencies.

/**
 * [Writer description]
 */
function BufferWriter() {
  this.buffer = [];
}

/**
 * [write description]
 * @param  {[type]} d    [description]
 * @param  {[type]} size [description]
 * @return {[type]}      [description]
 */
BufferWriter.prototype.write = function(d, size) {
  for (let i = 0; i < size; i++) {
    this.buffer.push((d & Math.pow(2, size - i - 1)) ? 1 : 0);
  }
};

/**
 * [writeBuffer description]
 * @param {[type]} b [description]
 */
BufferWriter.prototype.writeBuffer = function(b) {
  this.buffer = this.buffer.concat(b.buffer);
};

/**
 * [toBuffer description]
 * @return {[type]} [description]
 */
BufferWriter.prototype.toBuffer = function() {
  const arr = [];
  for (let i = 0; i < this.buffer.length; i += 8) {
    const chunk = this.buffer.slice(i, i + 8);
    arr.push(parseInt(chunk.join(''), 2));
  }
  return Buffer.from(arr);
};

module.exports = BufferWriter;