rfct: Split up session loading for readability

Now there are distinct steps to session loading. Regex was replaced
with a desktop file parsing library. This makes the code easier
to comprehend and allows for better flexibility in the future
(rharish101#67).

Cargo.toml

@@ -14,17 +14,15 @@ license = "GPL-3.0-or-later"
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [dependencies]
-chrono = { version = "0.4.22", default-features = false }
+async-recursion = "1.1.1"
 clap = { version = "4.1.4", features = ["derive"] }
 const_format = "0.2.26"
 derivative = "2.2.0"
 file-rotate = "0.7.2"
-glob = "0.3.0"
+freedesktop_entry_parser = "1.3.0"
 greetd_ipc = { version = "0.9.0", features = ["tokio-codec"] }
 gtk4 = "0.5"
-lru = "0.9.0"
 pwd = "1.4.0"
-regex = "1.7.1"
 relm4 = "0.5.0"
 serde = { version = "1.0.142", features = ["derive"] }
 serde-tuple-vec-map = "1.0.1"
@@ -35,7 +33,6 @@ toml = "0.6.0"
 tracing = "0.1.37"
 tracing-appender = "0.2.2"
 tracing-subscriber = { version = "0.3.16", features = ["local-time"] }
-tracker = "0.2.0"
 
 [features]
 gtk4_8 = ["gtk4/v4_8"]

src/constants.rs

@@ -48,9 +48,3 @@ pub const POWEROFF_CMD: &str = env_or!("POWEROFF_CMD", "poweroff");
 
 /// Default greeting message
 pub const GREETING_MSG: &str = "Welcome back!";
-
-/// Directories separated by `:`, containing desktop files for X11/Wayland sessions
-pub const SESSION_DIRS: &str = env_or!(
-    "SESSION_DIRS",
-    "/usr/share/xsessions:/usr/share/wayland-sessions"
-);

src/gui/component/auth_ui.rs

@@ -9,6 +9,7 @@ use tracing::error;
 use crate::greetd::Greetd;
 use crate::gui::component::greetd_controls::GreetdControlsInit;
 use crate::gui::component::{GreetdControlsOutput, SelectorInit, SelectorMsg, SelectorOutput};
+use crate::sysutil::SessionInfo;
 
 use super::greetd_controls::{GreetdControls, GreetdState};
 use super::{EntryOrDropDown, GreetdControlsMsg, Selector, SelectorOption};
@@ -23,7 +24,7 @@ where
 {
     pub initial_user: String,
     pub users: HashMap<String, String>,
-    pub sessions: HashMap<String, Vec<String>>,
+    pub sessions: HashMap<String, SessionInfo>,
 
     pub last_user_session_cache: HashMap<String, EntryOrDropDown>,
 
@@ -157,9 +158,9 @@ where
             .launch(SelectorInit {
                 entry_placeholder: "Session command".to_string(),
                 options: sessions
-                    .keys()
-                    .map(|name| SelectorOption {
-                        id: name.clone(),
+                    .iter()
+                    .map(|(xdg_id, SessionInfo { name, .. })| SelectorOption {
+                        id: xdg_id.clone(),
                         text: name.clone(),
                     })
                     .collect(),
@@ -172,7 +173,9 @@ where
                 let SelectorOutput::CurrentSelection(entry) = output;
                 let cmdline = match entry {
                     EntryOrDropDown::Entry(cmdline) => shlex::split(&cmdline),
-                    EntryOrDropDown::DropDown(id) => sessions.get(&id).cloned(),
+                    EntryOrDropDown::DropDown(id) => sessions
+                        .get(&id)
+                        .map(|SessionInfo { command, .. }| command.clone()),
                 };
 
                 Self::Input::SessionChanged(cmdline)

src/gui/component/greetd_controls.rs

@@ -319,7 +319,6 @@ where
                 GreetdState::NotCreated(_) => gtk::Box {
                     set_halign: gtk::Align::End,
                     #[template] LoginButton {
-                        #[watch]
                         grab_focus: (),
 
                         connect_clicked => GreetdControlsMsg::AdvanceAuthentication,

src/gui/component/mod.rs

@@ -10,7 +10,7 @@ use relm4::prelude::*;
 
 #[cfg(feature = "gtk4_8")]
 use crate::config::BgFit;
-use crate::greetd::Greetd;
+use crate::{greetd::Greetd, sysutil::SessionInfo};
 
 mod selector;
 pub use selector::*;
@@ -30,7 +30,7 @@ where
     Client: Greetd,
 {
     pub users: HashMap<String, String>,
-    pub sessions: HashMap<String, Vec<String>>,
+    pub sessions: HashMap<String, SessionInfo>,
 
     pub initial_user: String,
     pub last_user_session_cache: HashMap<String, EntryOrDropDown>,

src/main.rs

@@ -11,17 +11,18 @@ mod gui;
 mod sysutil;
 pub mod tomlutils;
 
+use std::collections::HashMap;
 use std::fs::{create_dir_all, OpenOptions};
 use std::io::{Result as IoResult, Write};
 use std::path::{Path, PathBuf};
 
-use cache::Cache;
+use cache::{Cache, SessionIdOrCmdline};
 use clap::{Parser, ValueEnum};
 use constants::CACHE_PATH;
 use file_rotate::{compression::Compression, suffix::AppendCount, ContentLimit, FileRotate};
 use greetd::MockGreetd;
 use gui::component::{App, AppInit, EntryOrDropDown, GreetdState};
-use sysutil::{SystemUsersAndSessions, User};
+use sysutil::SystemUsersAndSessions;
 use tracing::subscriber::set_global_default;
 use tracing::warn;
 use tracing_appender::{non_blocking, non_blocking::WorkerGuard};
@@ -31,6 +32,9 @@ use tracing_subscriber::{
 
 use crate::constants::{APP_ID, CONFIG_PATH, CSS_PATH, LOG_PATH};
 
+#[macro_use]
+extern crate async_recursion;
+
 #[cfg(test)]
 #[macro_use]
 extern crate test_case;
@@ -77,20 +81,29 @@ struct Args {
 }
 
 fn main() {
-    let args = Args::parse();
+    let Args {
+        logs,
+        log_level,
+        verbose,
+        config,
+        style,
+        demo,
+    } = Args::parse();
     // Keep the guard alive till the end of the function, since logging depends on this.
-    let _guard = init_logging(&args.logs, &args.log_level, args.verbose);
+    let _guard = init_logging(&logs, &log_level, verbose);
 
     // TODO: Is there a better way? we have to not start tokio until OffsetTime is initialized.
     // TODO: What on earth is this let binding?
-    let (cache, (SystemUsersAndSessions { users, sessions }, non_fatal_errors)) =
+    let (cache, SystemUsersAndSessions { users, sessions }) =
         tokio::runtime::Builder::new_current_thread()
             .enable_all()
             .build()
             .unwrap()
             .block_on(async {
-                let (cache, users) =
-                    tokio::join!(Cache::load(CACHE_PATH), SystemUsersAndSessions::load());
+                let (cache, users) = tokio::join!(
+                    Cache::load(CACHE_PATH),
+                    SystemUsersAndSessions::load(Vec::new())
+                );
 
                 (
                     cache.unwrap_or_else(|err| {
@@ -106,25 +119,29 @@ fn main() {
         .and_then(|user| users.contains_key(user).then_some(user.to_string()))
         .unwrap_or_else(|| users.keys().next().cloned().unwrap_or_default()); // TODO: Make Init accept an option
 
-    let last_user_session_cache = cache
+    let mut last_user_session_cache: HashMap<_, _> = cache
         .user_to_last_sess
         .into_iter()
         .filter_map(|(username, session)| match session {
-            cache::SessionIdOrCmdline::ID(id) => sessions
+            SessionIdOrCmdline::ID(id) => sessions
                 .contains_key(&id)
                 .then_some((username, EntryOrDropDown::DropDown(id))),
 
-            cache::SessionIdOrCmdline::Command(cmd) => {
-                Some((username, EntryOrDropDown::Entry(cmd)))
-            }
+            SessionIdOrCmdline::Command(cmd) => Some((username, EntryOrDropDown::Entry(cmd))),
         })
         .collect();
 
     let app = relm4::RelmApp::new(APP_ID);
 
     let users = users
         .into_iter()
-        .map(|(sys, User { full_name, .. })| (sys, full_name))
+        .map(|(sys, user)| {
+            if sessions.is_empty() {
+                last_user_session_cache
+                    .insert(sys.clone(), EntryOrDropDown::Entry(user.shell().to_owned()));
+            }
+            (sys, user.full_name)
+        })
         .collect();
 
     app.run::<App<MockGreetd>>(AppInit {