From 514904392cd32d17bc7fc99e1d22711fc6d055ef Mon Sep 17 00:00:00 2001
From: Hajime Hoshi <hajimehoshi@gmail.com>
Date: Sat, 23 Jan 2021 23:07:16 +0900
Subject: [PATCH] audio: Bug fix: Deadlock at acquiring the semaphore

Closes #1469
---
 audio/writerplayer.go | 17 ++++++++---------
 1 file changed, 8 insertions(+), 9 deletions(-)

diff --git a/audio/writerplayer.go b/audio/writerplayer.go
index 1c0dc1067..e9726fef1 100644
--- a/audio/writerplayer.go
+++ b/audio/writerplayer.go
@@ -168,9 +168,6 @@ func (p *writerPlayer) loop() {
 }
 
 func (p *writerPlayer) read() ([]byte, bool) {
-	p.m.Lock()
-	defer p.m.Unlock()
-
 	if p.context.hasError() {
 		return nil, false
 	}
@@ -179,18 +176,20 @@ func (p *writerPlayer) read() ([]byte, bool) {
 		return nil, false
 	}
 
+	p.context.acquireSemaphore()
+	defer func() {
+		p.context.releaseSemaphore()
+	}()
+
+	p.m.Lock()
+	defer p.m.Unlock()
+
 	// playing can be false when pausing.
 	if !p.playing {
 		return nil, false
 	}
 
 	const bufSize = 2048
-
-	p.context.acquireSemaphore()
-	defer func() {
-		p.context.releaseSemaphore()
-	}()
-
 	if p.readbuf == nil {
 		p.readbuf = make([]byte, bufSize)
 	}