From c2baa53ded315ed06cdebd96e07b1c6852d75920 Mon Sep 17 00:00:00 2001
From: Tal <83217276+talwat@users.noreply.github.com>
Date: Wed, 2 Oct 2024 22:56:01 +0200
Subject: [PATCH] fix: finally fix the alsa warnings with `libc`'s `freopen`

---
 Cargo.lock       |  3 ++-
 Cargo.toml       |  3 ++-
 src/play.rs      |  9 ---------
 src/player.rs    | 31 ++++++++++++++++++++++++++++---
 src/player/ui.rs | 10 ++--------
 5 files changed, 34 insertions(+), 22 deletions(-)

diff --git a/Cargo.lock b/Cargo.lock
index 316beb9..4057541 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -982,7 +982,7 @@ checksum = "a7a70ba024b9dc04c27ea2f0c0548feb474ec5c54bba33a7f72f873a39d07b24"
 
 [[package]]
 name = "lowfi"
-version = "1.3.1"
+version = "1.3.2"
 dependencies = [
  "Inflector",
  "arc-swap",
@@ -992,6 +992,7 @@ dependencies = [
  "eyre",
  "futures",
  "lazy_static",
+ "libc",
  "rand",
  "reqwest",
  "rodio",
diff --git a/Cargo.toml b/Cargo.toml
index 769a166..baf49ee 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "lowfi"
-version = "1.3.1"
+version = "1.3.2"
 edition = "2021"
 description = "An extremely simple lofi player."
 license = "MIT"
@@ -40,3 +40,4 @@ rodio = { version = "0.19.0", features = ["symphonia-mp3"], default-features = f
 crossterm = "0.28.1"
 Inflector = "0.11.4"
 lazy_static = "1.5.0"
+libc = "0.2.159"
diff --git a/src/play.rs b/src/play.rs
index 6d512d2..df1484e 100644
--- a/src/play.rs
+++ b/src/play.rs
@@ -1,9 +1,7 @@
 //! Responsible for the basic initialization & shutdown of the audio server & frontend.
 
-use std::io::stdout;
 use std::sync::Arc;
 
-use crossterm::cursor::SavePosition;
 use tokio::{sync::mpsc, task};
 
 use crate::player::Player;
@@ -12,13 +10,6 @@ use crate::player::{ui, Messages};
 /// Initializes the audio server, and then safely stops
 /// it when the frontend quits.
 pub async fn play(alternate: bool) -> eyre::Result<()> {
-    // Save the position. This is important since later on we can revert to this position
-    // and clear any potential error messages that may have showed up.
-    // TODO: Figure how to set some sort of flag to hide error messages within alsa/rodio,
-    // TODO: Instead of just ignoring & clearing them after.
-    // TODO: Fix this, as it doesn't work with some terminals when the cursor is at the bottom of the terminal.
-    crossterm::execute!(stdout(), SavePosition)?;
-
     let (tx, rx) = mpsc::channel(8);
 
     let player = Arc::new(Player::new().await?);
diff --git a/src/player.rs b/src/player.rs
index a7fae48..d1f787c 100644
--- a/src/player.rs
+++ b/src/player.rs
@@ -6,6 +6,7 @@ use std::{collections::VecDeque, sync::Arc, time::Duration};
 
 use arc_swap::ArcSwapOption;
 use downloader::Downloader;
+use libc::freopen;
 use reqwest::Client;
 use rodio::{OutputStream, OutputStreamHandle, Sink};
 use tokio::{
@@ -85,12 +86,34 @@ unsafe impl Send for Player {}
 unsafe impl Sync for Player {}
 
 impl Player {
+    /// This gets the output stream while also shutting up alsa.
+    fn get_output_stream() -> eyre::Result<(OutputStream, OutputStreamHandle)> {
+        extern "C" {
+            static stderr: *mut libc::FILE;
+        }
+
+        let mode = c"w".as_ptr();
+
+        // This is a bit of an ugly hack that basically just uses `libc` to redirect alsa's
+        // output to `/dev/null` so that it wont be shoved down our throats.
+
+        // SAFETY: Simple enough to be impossible to fail. Hopefully.
+        unsafe { freopen(c"/dev/null".as_ptr(), mode, stderr) };
+
+        let (stream, handle) = OutputStream::try_default()?;
+
+        // SAFETY: See the first call to `freopen`.
+        unsafe { freopen(c"/dev/tty".as_ptr(), mode, stderr) };
+
+        Ok((stream, handle))
+    }
+
     /// Initializes the entire player, including audio devices & sink.
     pub async fn new() -> eyre::Result<Self> {
-        let (_stream, handle) = OutputStream::try_default()?;
+        let (_stream, handle) = Self::get_output_stream()?;
         let sink = Sink::try_new(&handle)?;
 
-        Ok(Self {
+        let player = Self {
             tracks: RwLock::new(VecDeque::with_capacity(5)),
             current: ArcSwapOption::new(None),
             client: Client::builder()
@@ -104,7 +127,9 @@ impl Player {
             sink,
             _handle: handle,
             _stream,
-        })
+        };
+
+        Ok(player)
     }
 
     /// Just a shorthand for setting `current`.
diff --git a/src/player/ui.rs b/src/player/ui.rs
index e7cb8fa..643dbf3 100644
--- a/src/player/ui.rs
+++ b/src/player/ui.rs
@@ -13,7 +13,7 @@ use crate::tracks::TrackInfo;
 
 use super::Player;
 use crossterm::{
-    cursor::{Hide, MoveTo, MoveToColumn, MoveUp, RestorePosition, Show},
+    cursor::{Hide, MoveTo, MoveToColumn, MoveUp, Show},
     event::{self, KeyCode, KeyModifiers},
     style::{Print, Stylize},
     terminal::{self, Clear, ClearType, EnterAlternateScreen, LeaveAlternateScreen},
@@ -196,13 +196,7 @@ pub async fn start(
     sender: Sender<Messages>,
     alternate: bool,
 ) -> eyre::Result<()> {
-    crossterm::execute!(
-        stdout(),
-        RestorePosition,
-        Clear(ClearType::CurrentLine),
-        Clear(ClearType::FromCursorDown),
-        Hide
-    )?;
+    crossterm::execute!(stdout(), Hide)?;
 
     terminal::enable_raw_mode()?;