Prefix Buffers

[skeggse]

Buffers aren't prefixed, leading to behavior like this:

Which causes problems if you want to support arbitrary buffer data.

var msg = new Message;

msg.push(new Buffer('s:go'));

new Message(msg.toBuffer()).args
// => ['go']

At full speed parsing, this can happen in a matter of milliseconds.

var Message = require('..');

function unbuffer() {

  var start = process.hrtime();

  for (var i = 0;; i++) {
    var msg = new Message;
    var buf = new Buffer(4);

    buf[0] = (Math.random() * 256) | 0;
    buf[1] = (Math.random() * 256) | 0;
    buf[2] = 123;
    buf[3] = 125;

    msg.push(buf);

    var args = new Message(msg.toBuffer()).args;

    if (!Buffer.isBuffer(args[0])) {
      console.log('not a buffer', args[0]);
      return [start, process.hrtime()];
    }
  }

}

function ms(times) {
  return (times[1][0] * 1000 + times[1][1] / 1000000) -
    (times[0][0] * 1000 + times[0][1] / 1000000);
}

console.log(ms(unbuffer()) + ' ms');

not a buffer {}
228.04162900149822 ms
not a buffer {}
62.09908200055361 ms
not a buffer {}
100.19535400345922 ms
not a buffer {}
18.36940200254321 ms
not a buffer {}
68.66924300044775 ms
not a buffer {}
11.645527001470327 ms
not a buffer {}
190.55536199733615 ms
not a buffer {}
125.49566200003028 ms
not a buffer {}
111.19815300032496 ms
not a buffer {}
9.694663997739553 ms

[skeggse]

This would be fixed if I could get my optimized version to actually be faster 😒

[skeggse]

The problem, of course, with adding a prefix is that it's not backwards compatible...