Use parser-based unit value validation

Author: dannote

AGENTS.md

@@ -27,3 +27,9 @@ Integration tests are excluded by default. Enable them only inside a Linux syste
 ```sh
 SYSTEMD_INTEGRATION=1 mix test
 ```
+
+From macOS, prefer the checked-in wrapper for a full VM integration run:
+
+```sh
+scripts/integration_test.sh
+```

docs/RELEASE_CHECKLIST.md CONTRIBUTING.mddocs/RELEASE_CHECKLIST.md renamed to CONTRIBUTING.md

@@ -1,6 +1,6 @@
-# Release Checklist
+# Contributing
 
-Before publishing a pre-release or Hex package:
+Before opening release-oriented changes or publishing a pre-release/Hex package:
 
 - Run `mix ci` locally.
 - Run `mix docs` and inspect generated module examples.

README.md

@@ -79,4 +79,4 @@ Quick VM checks:
 ~/.local/bin/limactl shell systemd-test -- busctl --system list --no-pager
 ```
 
-See `docs/RELEASE_CHECKLIST.md` before publishing a release.
+See `CONTRIBUTING.md` before publishing a release.

lib/systemd/dbus/signature.ex

@@ -18,6 +18,8 @@ defmodule Systemd.DBus.Signature do
   defp primitive?(""), do: true
 
   defp primitive?(signature) do
-    String.match?(signature, ~r/^[syobintqxuagdvh]+$/)
+    signature
+    |> String.to_charlist()
+    |> Enum.all?(&(&1 in ~c"syobintqxuagdvh"))
   end
 end

lib/systemd/unit_file/parser.ex

@@ -155,10 +155,13 @@ defmodule Systemd.UnitFile.Parser do
   end
 
   defp first_non_whitespace_column(line) do
-    case Regex.run(~r/\S/, line, return: :index) do
-      [{index, _length}] -> index + 1
-      _no_match -> 1
-    end
+    line
+    |> :binary.bin_to_list()
+    |> Enum.with_index(1)
+    |> Enum.find_value(1, fn
+      {char, column} when char not in [?\s, ?\t] -> column
+      _whitespace -> false
+    end)
   end
 
   defp ensure_final_newline(text) do

lib/systemd/unit_file/validator.ex

@@ -2,7 +2,7 @@ defmodule Systemd.UnitFile.Validator do
   @moduledoc false
 
   alias Systemd.UnitFile
-  alias Systemd.UnitFile.{Directive, Section, ValidationError, Value}
+  alias Systemd.UnitFile.{Directive, Section, ValidationError, Value, ValueParser}
 
   @known_sections %{
     "service" => MapSet.new(["Unit", "Service", "Install"]),
@@ -273,10 +273,8 @@ defmodule Systemd.UnitFile.Validator do
     one_of(section, directive, String.downcase(value), ~w(1 yes true on 0 no false off), span)
   end
 
-  defp duration(_section, _directive, "infinity", _span), do: []
-
   defp duration(section, directive, value, span) do
-    if String.match?(value, ~r/^\d+(\.\d+)?\s*(us|µs|ms|s|sec|m|min|h|hr|d|day|w|week)?$/) do
+    if ValueParser.duration?(value) do
       []
     else
       [
@@ -292,7 +290,7 @@ defmodule Systemd.UnitFile.Validator do
   end
 
   defp octal_mode(section, directive, value, span) do
-    if String.match?(value, ~r/^[0-7]{3,4}$/) do
+    if ValueParser.octal_mode?(value) do
       []
     else
       [value_error(section, directive, value, "expected an octal mode such as 0660", span)]

lib/systemd/unit_file/value_parser.ex

@@ -0,0 +1,53 @@
+defmodule Systemd.UnitFile.ValueParser do
+  @moduledoc false
+
+  import NimbleParsec
+
+  digits = ascii_string([?0..?9], min: 1)
+  decimal = digits |> optional(ignore(string(".")) |> concat(digits))
+  spacing = repeat(choice([string(" "), string("\t")]))
+
+  duration_unit =
+    choice([
+      string("week"),
+      string("day"),
+      string("min"),
+      string("sec"),
+      string("hr"),
+      string("us"),
+      string("µs"),
+      string("ms"),
+      string("s"),
+      string("m"),
+      string("h"),
+      string("d"),
+      string("w")
+    ])
+
+  duration =
+    choice([
+      string("infinity"),
+      decimal |> ignore(spacing) |> optional(duration_unit)
+    ])
+    |> eos()
+
+  octal_mode = ascii_string([?0..?7], min: 3, max: 4) |> eos()
+
+  defparsecp(:parse_duration_value, duration)
+  defparsecp(:parse_octal_mode_value, octal_mode)
+
+  @doc false
+  @spec duration?(String.t()) :: boolean()
+  def duration?(value) when is_binary(value) do
+    parse_duration_value(value) |> parse_ok?()
+  end
+
+  @doc false
+  @spec octal_mode?(String.t()) :: boolean()
+  def octal_mode?(value) when is_binary(value) do
+    parse_octal_mode_value(value) |> parse_ok?()
+  end
+
+  defp parse_ok?({:ok, _tokens, "", _context, _line, _offset}), do: true
+  defp parse_ok?(_other), do: false
+end