From 713a69d08357ea813175ae1f9f87888ece2d9b36 Mon Sep 17 00:00:00 2001
From: Daniel Schaefer <git@danielschaefer.me>
Date: Sat, 10 Feb 2018 20:26:05 +0700
Subject: [PATCH] nixos/acpid: pass event parameters to handler (#34190)

Previously the parameters were just dropped. Now they can be read
from within the handler script. An example to show this is added.

Makes use of the new writeShellScript function as suggested in:
issue #21557

resolves:  #21557
---
 nixos/modules/services/hardware/acpid.nix | 32 +++++++++++++++++++----
 1 file changed, 27 insertions(+), 5 deletions(-)

diff --git a/nixos/modules/services/hardware/acpid.nix b/nixos/modules/services/hardware/acpid.nix
index bb17c8859d8..f69706ebff3 100644
--- a/nixos/modules/services/hardware/acpid.nix
+++ b/nixos/modules/services/hardware/acpid.nix
@@ -31,7 +31,7 @@ let
           ''
             fn=$out/${name}
             echo "event=${handler.event}" > $fn
-            echo "action=${pkgs.writeScript "${name}.sh" (concatStringsSep "\n" [ "#! ${pkgs.bash}/bin/sh" handler.action ])}" >> $fn
+            echo "action=${pkgs.writeShellScriptBin "${name}.sh" handler.action }/bin/${name}.sh '%e'" >> $fn
           '';
         in concatStringsSep "\n" (mapAttrsToList f (canonicalHandlers // config.services.acpid.handlers))
       }
@@ -69,11 +69,33 @@ in
           };
         });
 
-        description = "Event handlers.";
+        description = ''
+          Event handlers.
+
+          <note><para>
+            Handler can be a single command.
+          </para></note>
+        '';
         default = {};
-        example = { mute = { event = "button/mute.*"; action = "amixer set Master toggle"; }; };
-
-
+        example = {
+          ac-power = {
+            event = "ac_adapter/*";
+            action = ''
+              vals=($1)  # space separated string to array of multiple values
+              case ''${vals[3]} in
+                  00000000)
+                      echo unplugged >> /tmp/acpi.log
+                      ;;
+                  00000001)
+                      echo plugged in >> /tmp/acpi.log
+                      ;;
+                  *)
+                      echo unknown >> /tmp/acpi.log
+                      ;;
+              esac
+            '';
+          };
+        };
       };
 
       powerEventCommands = mkOption {