From e6eb3e70249c2edd47cc117748c7f6a05572d871 Mon Sep 17 00:00:00 2001
From: Dee-Jay Logozzo <git@djlogozzo.com>
Date: Fri, 19 Nov 2021 19:43:46 +1100
Subject: [PATCH] Replaced the simple sleep wait, with a tokio `Notify` barrier
 This is still a fairly simple band-aid solution, however it is a more eligant
 solution as it removes the free-running aspect of the loop entirely, only
 processing the possibility of a `power_command` if we've been notified that
 there is one to process

---
 src/greeter.rs | 3 ++-
 src/main.rs    | 5 +++--
 src/power.rs   | 1 +
 3 files changed, 6 insertions(+), 3 deletions(-)

diff --git a/src/greeter.rs b/src/greeter.rs
index 605e880..3121a2f 100644
--- a/src/greeter.rs
+++ b/src/greeter.rs
@@ -14,7 +14,7 @@ use i18n_embed::DesktopLanguageRequester;
 use tokio::{
   net::UnixStream,
   process::Command,
-  sync::{RwLock, RwLockWriteGuard},
+  sync::{Notify, RwLock, RwLockWriteGuard},
 };
 use zeroize::Zeroize;
 
@@ -87,6 +87,7 @@ pub struct Greeter {
 
   pub power_commands: HashMap<PowerOption, String>,
   pub power_command: Option<Command>,
+  pub power_command_notify: Arc<Notify>,
   pub power_setsid: bool,
 
   pub working: bool,
diff --git a/src/main.rs b/src/main.rs
index 50fb132..5cce98e 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -70,16 +70,17 @@ async fn run() -> Result<(), Box<dyn Error>> {
 
   tokio::task::spawn({
     let greeter = greeter.clone();
+    let notify = greeter.read().await.power_command_notify.clone();
 
     async move {
       loop {
+        notify.notified().await;
+
         let command = greeter.write().await.power_command.take();
 
         if let Some(command) = command {
           power::run(&greeter, command).await;
         }
-        
-        tokio::time::sleep(std::time::Duration::from_millis(100)).await
       }
     }
   });
diff --git a/src/power.rs b/src/power.rs
index 245477f..9a0f688 100644
--- a/src/power.rs
+++ b/src/power.rs
@@ -50,6 +50,7 @@ pub fn power(greeter: &mut Greeter, option: PowerOption) {
   };
 
   greeter.power_command = Some(command);
+  greeter.power_command_notify.notify_one();
 }
 
 pub async fn run(greeter: &Arc<RwLock<Greeter>>, mut command: Command) {