Remove the need for rust nightly

My pidfd implmentation is simple enough, and Option.contains() is not
worth requiring nightly.

Dockerfile

@@ -9,7 +9,7 @@ RUN apt-get update && \
     apt-get -y install curl devscripts && \
     mkdir -p /build
 
-RUN curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh -s -- -y --default-toolchain nightly
+RUN curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh -s -- -y
 
 # Do this first to get our build deps cached.
 COPY debian ./debian

Makefile

@@ -44,13 +44,6 @@ RELEASE_MANPAGES := $(addprefix $(RELEASE_OUT)/,$(MANPAGES))
 INSTALL ?= install
 HELP2MAN ?= help2man
 
-RUST_RELEASE_CHANNEL = nightly
-ifeq ($(RUST_RELEASE_CHANNEL),nightly)
-	RUST_RELEASE_CHANNEL_ARG = +nightly
-else
-	FEATURES_ARGS = --no-default-features
-endif
-
 DEV_LOG_LEVEL = debug
 
 all: release manpages $(RELEASE_OUT)/bscreensaver-settings.desktop
@@ -70,10 +63,10 @@ install: all
 	$(INSTALL) -m 0644 $(RELEASE_MANPAGES) $(DESTDIR)$(MANDIR)/man1
 
 $(DEV_TARGETS): $(SOURCES)
-	HELPER_DIR=target/debug cargo $(RUST_RELEASE_CHANNEL_ARG) build $(FEATURES_ARGS)
+	HELPER_DIR=target/debug cargo build
 
 $(RELEASE_TARGETS): $(SOURCES)
-	HELPER_DIR=$(HELPER_DIR) cargo $(RUST_RELEASE_CHANNEL_ARG) build $(FEATURES_ARGS) --release
+	HELPER_DIR=$(HELPER_DIR) cargo build --release
 
 $(RELEASE_OUT)/%.1.gz: $(RELEASE_OUT)/%.1
 	mkdir -p $(dir $@)
@@ -101,7 +94,7 @@ deb-pkg:
 		rm -rf /build/bscreensaver'
 
 clean:
-	cargo $(RUST_RELEASE_CHANNEL_ARG) clean
+	cargo clean
 
 uninstall:
 	rm -f $(addprefix $(DESTDIR)$(BINDIR),$(BINARIES)) $(addprefix $(HELPER_DIR)/,$(HELPERS))) || true
@@ -118,10 +111,10 @@ run: $(DEV_TARGETS)
 	BSCREENSAVER_SYSTEMD_LOG=$(DEV_LOG_LEVEL) \
 	BSCREENSAVER_DIALOG_GTK3_LOG=$(DEV_LOG_LEVEL) \
 	HELPER_DIR=target/debug \
-	cargo $(RUST_RELEASE_CHANNEL_ARG) run $(FEATURES_ARGS) --bin bscreensaver
+	cargo run --bin bscreensaver
 
 run-dialog:
 	RUST_BACKTRACE=1 \
 	BSCREENSAVER_DIALOG_GTK3_LOG=$(DEV_LOG_LEVEL) \
 	BSCREENSAVER_DIALOG_STANDALONE=1 \
-	cargo $(RUST_RELEASE_CHANNEL_ARG) run $(FEATURES_ARGS) --bin bscreensaver-dialog-gtk3
+	cargo run --bin bscreensaver-dialog-gtk3

dbus-service/src/main.rs

@@ -6,6 +6,7 @@ use std::{io, process::exit, time::{Duration, Instant}};
 use zbus::{dbus_interface, fdo::{self, DBusProxy, RequestNameFlags}, names::{BusName, UniqueName, WellKnownName}, ConnectionBuilder, MessageHeader};
 
 use bscreensaver_command::{bscreensaver_command, BCommand};
+use bscreensaver_util::opt_contains;
 
 const OUR_DBUS_NAME: &str = "org.freedesktop.ScreenSaver";
 const HEARTBEAT_INTERVAL: Duration = Duration::from_secs(45);
@@ -157,7 +158,7 @@ async fn dbus_task(state: Arc<Mutex<State>>) -> anyhow::Result<()> {
             let args = name_owner_changed.args()?;
             match args.name() {
                 BusName::WellKnown(name) if name == OUR_DBUS_NAME => {
-                    if args.new_owner().is_none() || args.new_owner().as_ref().filter(|no| no != &our_unique_name).is_some() {
+                    if args.new_owner().is_none() || opt_contains(&args.new_owner(), &our_unique_name) {
                         info!("Lost bus name {}; quitting", OUR_DBUS_NAME);
                         exit(0);
                     }

debian/rules

@@ -1,10 +1,6 @@
 #!/usr/bin/make -f
 
-
-RUST_RELEASE_CHANNEL = nightly
-
 MAKE_ARGS = \
-	RUST_RELEASE_CHANNEL=$(RUST_RELEASE_CHANNEL) \
 	PREFIX=/usr \
 	SYSCONFDIR=/etc \
 	DESTDIR=debian/bscreensaver

locker/Cargo.toml

@@ -12,10 +12,6 @@ readme = "README.md"
 keywords = ["gui", "screensaver", "screen-locker"]
 categories = ["gui"]
 
-[features]
-default = ["use-nightly"]
-use-nightly = []
-
 [dependencies]
 anyhow = "1"
 clap = "3"

locker/src/main.rs

@@ -1,7 +1,3 @@
-#![cfg_attr(feature = "use-nightly", feature(linux_pidfd))]
-#![cfg_attr(feature = "use-nightly", feature(option_result_contains))]
-
-#[cfg(not(feature = "use-nightly"))]
 mod pidfd;
 
 use clap::{Arg, Command as ClapCommand};
@@ -31,10 +27,6 @@ use xcb_xembed::embedder::Embedder;
 
 use bscreensaver_command::{BCommand, create_command_window};
 use bscreensaver_util::{*, settings::Configuration};
-
-#[cfg(feature = "use-nightly")]
-use std::os::linux::process::{ChildExt, CommandExt, PidFd};
-#[cfg(not(feature = "use-nightly"))]
 use pidfd::{CreatePidFd, PidFd};
 
 const BLANKED_ARG: &str = "blanked";
@@ -454,14 +446,8 @@ fn create_blanker_windows(conn: &xcb::Connection) -> xcb::Result<Vec<Monitor>> {
 }
 
 fn start_subservice(binary_name: &str) -> anyhow::Result<(Child, PidFd)> {
-    let mut command = Command::new(format!("{}/{}", env!("HELPER_DIR"), binary_name));
+    let child = Command::new(format!("{}/{}", env!("HELPER_DIR"), binary_name))
-    #[cfg(feature = "use-nightly")]
+        .spawn()?;
-    command.create_pidfd(true);
-    let mut child = command.spawn()?;
-
-    #[cfg(feature = "use-nightly")]
-    let pidfd = child.take_pidfd()?;
-    #[cfg(not(feature = "use-nightly"))]
     let pidfd = child.create_pidfd()?;
 
     Ok((child, pidfd))
@@ -713,18 +699,12 @@ fn start_unlock_dialog<'a>(conn: &'a xcb::Connection, state: &State<'a>, trigger
 
     show_cursor(conn, state);
 
-    let mut command = Command::new(format!("{}/{}", env!("HELPER_DIR"), state.config.dialog_backend.binary_name()));
+    let mut child = Command::new(format!("{}/{}", env!("HELPER_DIR"), state.config.dialog_backend.binary_name()))
-    #[cfg(feature = "use-nightly")]
-    command.create_pidfd(true);
-    let mut child = command
         .stdout(Stdio::piped())
         .spawn()?;
 
-    let mut child_out = child.stdout.take().unwrap();
-    #[cfg(feature = "use-nightly")]
-    let child_pidfd = child.take_pidfd()?;
-    #[cfg(not(feature = "use-nightly"))]
     let child_pidfd = child.create_pidfd()?;
+    let mut child_out = child.stdout.take().unwrap();
 
     let mut xid_buf: [u8; 4] = [0; 4];
     child_out.read_exact(&mut xid_buf)?;
@@ -983,12 +963,3 @@ fn kill_child_processes(state: &mut State) -> anyhow::Result<()> {
 
     Ok(())
 }
-
-fn opt_contains<T: PartialEq>(o: &Option<T>, v: &T) -> bool {
-    #[cfg(feature = "use-nightly")]
-    let res = o.contains(v);
-    #[cfg(not(feature = "use-nightly"))]
-    let res = o.as_ref().filter(|ov| ov == &v).is_some();
-
-    res
-}

locker/src/pidfd.rs

@@ -21,13 +21,11 @@ fn pidfd_open(pid: RawFd) -> nix::Result<PidFd> {
 pub struct PidFd(RawFd);
 
 pub trait CreatePidFd {
-    // mut isn't necessary here, but it is for the nightly PidFd stuff,
+    fn create_pidfd(&self) -> nix::Result<PidFd>;
-    // so keep it like this to avoid a warning when compiling using stable.
-    fn create_pidfd(&mut self) -> nix::Result<PidFd>;
 }
 
 impl CreatePidFd for Child {
-    fn create_pidfd(&mut self) -> nix::Result<PidFd> {
+    fn create_pidfd(&self) -> nix::Result<PidFd> {
         pidfd_open(self.id() as RawFd)
     }
 }

util/src/lib.rs

@@ -12,6 +12,10 @@ pub fn init_logging(env_name: &str) {
         .init();
 }
 
+pub fn opt_contains<T: PartialEq>(o: &Option<T>, v: &T) -> bool {
+    o.as_ref().filter(|ov| ov == &v).is_some()
+}
+
 pub fn create_atom(conn: &xcb::Connection, name: &[u8]) -> xcb::Result<x::Atom> {
     let cookie = conn.send_request(&x::InternAtom {
         only_if_exists: false,