Allow configuration through a TOML file (#156).

Cargo.toml

@@ -46,6 +46,8 @@ tracing-appender = "0.2.3"
 tracing-subscriber = "0.3.18"
 tracing = "0.1.40"
 utmp-rs = "0.3.0"
+serde = { version = "1.0.210", features = ["serde_derive"] }
+toml = "0.8.19"
 
 [profile.release]
 lto = true

src/config/file.rs

@@ -0,0 +1,78 @@
+use std::{error::Error, path::PathBuf};
+
+use serde::Deserialize;
+
+use crate::Greeter;
+
+#[derive(Debug, Default, Deserialize)]
+pub struct FileConfig {
+  #[serde(default)]
+  pub defaults: Defaults,
+  #[serde(default)]
+  pub sessions: Sessions,
+  #[serde(default)]
+  pub remember: Remember,
+  #[serde(default)]
+  pub ui: Ui,
+}
+
+#[derive(Debug, Default, Deserialize)]
+pub struct Defaults {
+  pub debug: Option<String>,
+  pub command: Option<String>,
+  pub env: Option<Vec<String>>,
+  pub user_min_uid: Option<u16>,
+  pub user_max_uid: Option<u16>,
+  #[serde(default)]
+  pub power_no_setsid: bool,
+  pub shutdown_command: Option<String>,
+  pub reboot_command: Option<String>,
+}
+
+#[derive(Debug, Default, Deserialize)]
+pub struct Sessions {
+  pub wayland_paths: Option<Vec<PathBuf>>,
+  pub wayland_wrapper: Option<String>,
+  pub x11_paths: Option<Vec<PathBuf>>,
+  pub x11_wrapper: Option<String>,
+  #[serde(default)]
+  pub x11_wrapper_disabled: bool,
+}
+
+#[derive(Debug, Default, Deserialize)]
+pub struct Remember {
+  #[serde(default)]
+  pub last_user: bool,
+  #[serde(default)]
+  pub last_session: bool,
+  #[serde(default)]
+  pub last_user_session: bool,
+}
+
+#[derive(Debug, Default, Deserialize)]
+pub struct Ui {
+  pub greeting: Option<String>,
+  #[serde(default)]
+  pub use_issue: bool,
+  #[serde(default)]
+  pub show_time: bool,
+  pub time_format: Option<String>,
+  #[serde(default)]
+  pub show_user_menu: bool,
+  #[serde(default)]
+  pub show_asterisks: bool,
+  pub asterisks_char: Option<char>,
+  pub width: Option<u64>,
+  pub window_padding: Option<u64>,
+  pub container_padding: Option<u64>,
+  pub prompt_padding: Option<u64>,
+  pub command_f_key: Option<u8>,
+  pub sessions_f_key: Option<u8>,
+  pub power_f_key: Option<u8>,
+}
+
+impl Greeter {
+  pub fn parse_config_file(&mut self, file: &str) -> Result<FileConfig, Box<dyn Error>> {
+    Ok(toml::from_str::<FileConfig>(file)?)
+  }
+}

src/config/mod.rs

@@ -0,0 +1,2 @@
+pub mod file;
+pub mod parser;