stockholm/Zpkgs/tv/genid.nix
2015-07-19 16:20:16 +02:00

22 lines
437 B
Nix

{ lib, pkgs, ... }:
pkgs.writeScriptBin "genid" ''
#! /bin/sh
# usage: genid NAME
set -euf
export PATH=${lib.makeSearchPath "bin" (with pkgs; [
bc
coreutils
])}
name=$1
hash=$(printf %s "$name" | sha1sum | cut -d\ -f1 | tr a-f A-F)
echo "
min=2^16 # bigger than nobody and nogroup, see <nixos/modules/misc/ids.nix>
max=2^32 # see 2^(8*sizeof(uid_t))
ibase=16
($hash + min) % max
" | bc
''