Merge commit '3239fd2b8f728106491154b44625662e10259af2'

Conflicts:
	nixpkgs/pkgs/applications/window-managers/sway/default.nix

1 files changed, 23 insertions, 2 deletions

diff --git a/nixpkgs/nixos/lib/utils.nix b/nixpkgs/nixos/lib/utils.nix
index 190c4db4d49d..ae68c3920c5b 100644
--- a/nixpkgs/nixos/lib/utils.nix
+++ b/nixpkgs/nixos/lib/utils.nix
@@ -45,6 +45,26 @@ rec {
    replaceChars ["/" "-" " "] ["-" "\\x2d" "\\x20"]
    (removePrefix "/" s);
 
+  # Quotes an argument for use in Exec* service lines.
+  # systemd accepts "-quoted strings with escape sequences, toJSON produces
+  # a subset of these.
+  # Additionally we escape % to disallow expansion of % specifiers. Any lone ;
+  # in the input will be turned it ";" and thus lose its special meaning.
+  # Every $ is escaped to $$, this makes it unnecessary to disable environment
+  # substitution for the directive.
+  escapeSystemdExecArg = arg:
+    let
+      s = if builtins.isPath arg then "${arg}"
+        else if builtins.isString arg then arg
+        else if builtins.isInt arg || builtins.isFloat arg then toString arg
+        else throw "escapeSystemdExecArg only allows strings, paths and numbers";
+    in
+      replaceChars [ "%" "$" ] [ "%%" "$$" ] (builtins.toJSON s);
+
+  # Quotes a list of arguments into a single string for use in a Exec*
+  # line.
+  escapeSystemdExecArgs = concatMapStringsSep " " escapeSystemdExecArg;
+
   # Returns a system path for a given shell package
   toShellPath = shell:
     if types.shellPackage.check shell then
@@ -150,7 +170,8 @@ rec {
         rm '${output}'
       fi
 
-      inherit_errexit_restore=$(shopt -p inherit_errexit)
+      inherit_errexit_enabled=0
+      shopt -pq inherit_errexit && inherit_errexit_enabled=1
       shopt -s inherit_errexit
     ''
     + concatStringsSep
@@ -170,7 +191,7 @@ rec {
       ' <<'EOF'
       ${builtins.toJSON set}
       EOF
-      $inherit_errexit_restore
+      (( ! $inherit_errexit_enabled )) && shopt -u inherit_errexit
     '';
 
   systemdUtils = {