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authortv <tv@shackspace.de>2015-07-24 23:19:49 +0200
committertv <tv@shackspace.de>2015-07-24 23:19:49 +0200
commit78c12a8adca9f55e8faa5c86f102050c8a557b64 (patch)
treeab1a213b369a4dde4f437ad3e73e310c1497688f /Zpkgs/krebs/genid.nix
parent103c00849e126aa592af0a7fb47c84312ca50304 (diff)
Zpkgs {tv -> krebs} genid
Diffstat (limited to 'Zpkgs/krebs/genid.nix')
-rw-r--r--Zpkgs/krebs/genid.nix22
1 files changed, 22 insertions, 0 deletions
diff --git a/Zpkgs/krebs/genid.nix b/Zpkgs/krebs/genid.nix
new file mode 100644
index 000000000..c75bec317
--- /dev/null
+++ b/Zpkgs/krebs/genid.nix
@@ -0,0 +1,22 @@
+{ 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 "$name" | sha1sum | cut -d\ -f1 | tr a-f A-F)
+ echo "
+ min=2^24 # bigger than nobody and nogroup, see <nixos/modules/misc/ids.nix>
+ # and some spare for stuff like lxd.
+ max=2^32 # see 2^(8*sizeof(uid_t))
+ ibase=16
+ ($hash + min) % max
+ " | bc
+''