From fbb2022b25782bb67ef2e651ec3ece8cfb948831 Mon Sep 17 00:00:00 2001
From: Mathieu Duponchelle <mathieu@centricular.com>
Date: Wed, 22 Apr 2020 01:55:51 +0200
Subject: [PATCH] tttocea608: protect State with a simple mutex

There was no reason to use AtomicRefcell in this context,
aside from the dubious pleasure of panicing when attempting
to borrow mutably while another mutable borrow was already
held.

Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-rs/-/merge_requests/314>
---
 video/closedcaption/src/tttocea608.rs | 24 ++++++++++++------------
 1 file changed, 12 insertions(+), 12 deletions(-)

diff --git a/video/closedcaption/src/tttocea608.rs b/video/closedcaption/src/tttocea608.rs
index c708a11a..14824577 100644
--- a/video/closedcaption/src/tttocea608.rs
+++ b/video/closedcaption/src/tttocea608.rs
@@ -24,7 +24,7 @@ use gst::prelude::*;
 use gst::subclass::prelude::*;
 
 use super::cea608tott_ffi as ffi;
-use atomic_refcell::AtomicRefCell;
+use std::sync::Mutex;
 
 fn scale_round(val: u64, num: u64, denom: u64) -> u64 {
     unsafe { gst_sys::gst_util_uint64_scale_round(val, num, denom) }
@@ -183,7 +183,7 @@ struct TtToCea608 {
     srcpad: gst::Pad,
     sinkpad: gst::Pad,
 
-    state: AtomicRefCell<State>,
+    state: Mutex<State>,
 }
 
 lazy_static! {
@@ -203,7 +203,7 @@ impl TtToCea608 {
         new_frame_no: u64,
     ) -> Result<gst::FlowSuccess, gst::FlowError> {
         if last_frame_no != new_frame_no {
-            let state = self.state.borrow_mut();
+            let state = self.state.lock().unwrap();
             let (fps_n, fps_d) = (
                 *state.framerate.numer() as u64,
                 *state.framerate.denom() as u64,
@@ -235,7 +235,7 @@ impl TtToCea608 {
         min_frame_no: u64,
         mut erase_display_frame_no: u64,
     ) -> Result<gst::FlowSuccess, gst::FlowError> {
-        let mut state = self.state.borrow_mut();
+        let mut state = self.state.lock().unwrap();
 
         let (fps_n, fps_d) = (
             *state.framerate.numer() as u64,
@@ -291,7 +291,7 @@ impl TtToCea608 {
             duration => Ok(duration),
         }?;
 
-        let mut state = self.state.borrow_mut();
+        let mut state = self.state.lock().unwrap();
         let mut buffers = vec![];
 
         {
@@ -474,7 +474,7 @@ impl TtToCea608 {
                 let ret = self.sinkpad.peer_query(&mut peer_query);
 
                 if ret {
-                    let state = self.state.borrow();
+                    let state = self.state.lock().unwrap();
                     let (live, mut min, mut max) = peer_query.get_result();
                     let (fps_n, fps_d) = (
                         *state.framerate.numer() as u64,
@@ -525,7 +525,7 @@ impl TtToCea608 {
                 );
                 s.fixate();
 
-                let mut state = self.state.borrow_mut();
+                let mut state = self.state.lock().unwrap();
                 state.framerate = s.get_some::<gst::Fraction>("framerate").unwrap();
 
                 gst_debug!(CAT, obj: pad, "Pushing caps {}", caps);
@@ -537,7 +537,7 @@ impl TtToCea608 {
                 return self.srcpad.push_event(new_event);
             }
             EventView::Gap(e) => {
-                let mut state = self.state.borrow_mut();
+                let mut state = self.state.lock().unwrap();
                 let (fps_n, fps_d) = (
                     *state.framerate.numer() as u64,
                     *state.framerate.denom() as u64,
@@ -571,7 +571,7 @@ impl TtToCea608 {
                 return true;
             }
             EventView::Eos(_) => {
-                let mut state = self.state.borrow_mut();
+                let mut state = self.state.lock().unwrap();
                 if let Some(erase_display_frame_no) = state.erase_display_frame_no {
                     let min_frame_no = state.last_frame_no;
                     state.erase_display_frame_no = None;
@@ -633,7 +633,7 @@ impl ObjectSubclass for TtToCea608 {
         Self {
             srcpad,
             sinkpad,
-            state: AtomicRefCell::new(State::default()),
+            state: Mutex::new(State::default()),
         }
     }
 
@@ -699,7 +699,7 @@ impl ElementImpl for TtToCea608 {
 
         match transition {
             gst::StateChange::ReadyToPaused => {
-                let mut state = self.state.borrow_mut();
+                let mut state = self.state.lock().unwrap();
                 *state = State::default();
             }
             _ => (),
@@ -709,7 +709,7 @@ impl ElementImpl for TtToCea608 {
 
         match transition {
             gst::StateChange::PausedToReady => {
-                let mut state = self.state.borrow_mut();
+                let mut state = self.state.lock().unwrap();
                 *state = State::default();
             }
             _ => (),