moby/vendor/github.com/sean-/seed

seed - Quickly Seed Go's Random Number Generator

Boiler-plate to securely seed Go's random number generator (if possible). This library isn't anything fancy, it's just a canonical way of seeding Go's random number generator. Cribbed from Nomad before it was moved into Consul and made into a helper function, and now further modularized to be a super lightweight and reusable library.

Time is better than Go's default seed of 1, but friends don't let friends use time as a seed to a random number generator. Use seed.MustInit() instead.

seed.Init() is an idempotent and reentrant call that will return an error if it can't seed the value the first time it is called. Init() is reentrant.

seed.MustInit() is idempotent and reentrant call that will panic() if it can't seed the value the first time it is called. MustInit() is reentrant.

Usage

package mypackage

import (
  "github.com/sean-/seed"
)

// MustInit will panic() if it is unable to set a high-entropy random seed:
func init() {
  seed.MustInit()
}

// Or if you want to not panic() and can actually handle this error:
func init() {
  if secure, err := !seed.Init(); !secure {
    // Handle the error
    //panic(fmt.Sprintf("Unable to securely seed Go's RNG: %v", err))
  }
}