pbf with varint64 as string support

pbf.coffee

Pbf = require 'pbf'
ByteBuffer = require 'bytebuffer'

Pbf.prototype.readVarint64 = ->
  res = ByteBuffer.prototype.readVarint64.call(
    buffer: this.buf,
    noAssert: true,
    offset: 0
  , this.pos)
  this.pos += res.length
  res.value.toString()

Pbf.prototype.writeVarint64 = (val) ->
  this.realloc(10)
  this.pos += ByteBuffer.prototype.writeVarint64.call({
    buffer: this.buf
    noAssert: true
    offset: 0
  }, val, this.pos)

Pbf.prototype.writeVarint64Field = (tag, val) ->
  this.writeTag(tag, Pbf.Varint)
  this.writeVarint64(val)

module.exports = Pbf