output/Control: pass std::unique_lock<> to Cond::wait()

src/output/Control.cxx

@@ -112,10 +112,10 @@ AudioOutputControl::LockToggleEnabled() noexcept
 }
 
 void
-AudioOutputControl::WaitForCommand() noexcept
+AudioOutputControl::WaitForCommand(std::unique_lock<Mutex> &lock) noexcept
 {
 	while (!IsCommandFinished())
-		client_cond.wait(mutex);
+		client_cond.wait(lock);
 }
 
 void
@@ -128,17 +128,18 @@ AudioOutputControl::CommandAsync(Command cmd) noexcept
 }
 
 void
-AudioOutputControl::CommandWait(Command cmd) noexcept
+AudioOutputControl::CommandWait(std::unique_lock<Mutex> &lock,
+				Command cmd) noexcept
 {
 	CommandAsync(cmd);
-	WaitForCommand();
+	WaitForCommand(lock);
 }
 
 void
 AudioOutputControl::LockCommandWait(Command cmd) noexcept
 {
-	const std::lock_guard<Mutex> protect(mutex);
-	CommandWait(cmd);
+	std::unique_lock<Mutex> lock(mutex);
+	CommandWait(lock, cmd);
 }
 
 void
@@ -189,7 +190,8 @@ AudioOutputControl::EnableDisableAsync()
 }
 
 inline bool
-AudioOutputControl::Open(const AudioFormat audio_format,
+AudioOutputControl::Open(std::unique_lock<Mutex> &lock,
+			 const AudioFormat audio_format,
 			 const MusicPipe &mp) noexcept
 {
 	assert(allow_play);
@@ -218,7 +220,7 @@ AudioOutputControl::Open(const AudioFormat audio_format,
 		}
 	}
 
-	CommandWait(Command::OPEN);
+	CommandWait(lock, Command::OPEN);
 	const bool open2 = open;
 
 	if (open2 && output->mixer != nullptr) {
@@ -236,7 +238,7 @@ AudioOutputControl::Open(const AudioFormat audio_format,
 }
 
 void
-AudioOutputControl::CloseWait() noexcept
+AudioOutputControl::CloseWait(std::unique_lock<Mutex> &lock) noexcept
 {
 	assert(allow_play);
 
@@ -246,7 +248,7 @@ AudioOutputControl::CloseWait() noexcept
 	assert(!open || !fail_timer.IsDefined());
 
 	if (open)
-		CommandWait(Command::CLOSE);
+		CommandWait(lock, Command::CLOSE);
 	else
 		fail_timer.Reset();
 }
@@ -256,15 +258,15 @@ AudioOutputControl::LockUpdate(const AudioFormat audio_format,
 			       const MusicPipe &mp,
 			       bool force) noexcept
 {
-	const std::lock_guard<Mutex> protect(mutex);
+	std::unique_lock<Mutex> lock(mutex);
 
 	if (enabled && really_enabled) {
 		if (force || !fail_timer.IsDefined() ||
 		    fail_timer.Check(REOPEN_AFTER * 1000)) {
-			return Open(audio_format, mp);
+			return Open(lock, audio_format, mp);
 		}
 	} else if (IsOpen())
-		CloseWait();
+		CloseWait(lock);
 
 	return false;
 }
@@ -355,13 +357,13 @@ AudioOutputControl::LockRelease() noexcept
 		   mixer_auto_close()) */
 		mixer_auto_close(output->mixer);
 
-	const std::lock_guard<Mutex> protect(mutex);
+	std::unique_lock<Mutex> lock(mutex);
 
 	assert(!open || !fail_timer.IsDefined());
 	assert(allow_play);
 
 	if (IsOpen())
-		CommandWait(Command::RELEASE);
+		CommandWait(lock, Command::RELEASE);
 	else
 		fail_timer.Reset();
 }
@@ -371,8 +373,8 @@ AudioOutputControl::LockCloseWait() noexcept
 {
 	assert(!open || !fail_timer.IsDefined());
 
-	const std::lock_guard<Mutex> protect(mutex);
-	CloseWait();
+	std::unique_lock<Mutex> lock(mutex);
+	CloseWait(lock);
 }
 
 void

src/output/Control.hxx

@@ -307,11 +307,11 @@ public:
 	 *
 	 * Caller must lock the mutex.
 	 */
-	void WaitForCommand() noexcept;
+	void WaitForCommand(std::unique_lock<Mutex> &lock) noexcept;
 
 	void LockWaitForCommand() noexcept {
-		const std::lock_guard<Mutex> protect(mutex);
-		WaitForCommand();
+		std::unique_lock<Mutex> lock(mutex);
+		WaitForCommand(lock);
 	}
 
 	/**
@@ -326,7 +326,7 @@ public:
 	 *
 	 * Caller must lock the mutex.
 	 */
-	void CommandWait(Command cmd) noexcept;
+	void CommandWait(std::unique_lock<Mutex> &lock, Command cmd) noexcept;
 
 	/**
 	 * Lock the object and execute the command synchronously.
@@ -368,7 +368,7 @@ public:
 
 	void LockPauseAsync() noexcept;
 
-	void CloseWait() noexcept;
+	void CloseWait(std::unique_lock<Mutex> &lock) noexcept;
 	void LockCloseWait() noexcept;
 
 	/**
@@ -391,7 +391,8 @@ public:
 	/**
 	 * Caller must lock the mutex.
 	 */
-	bool Open(AudioFormat audio_format, const MusicPipe &mp) noexcept;
+	bool Open(std::unique_lock<Mutex> &lock,
+		  AudioFormat audio_format, const MusicPipe &mp) noexcept;
 
 	/**
 	 * Opens or closes the device, depending on the "enabled"
@@ -522,7 +523,7 @@ private:
 	 * @return true if playback should be continued, false if a
 	 * command was issued
 	 */
-	bool WaitForDelay() noexcept;
+	bool WaitForDelay(std::unique_lock<Mutex> &lock) noexcept;
 
 	/**
 	 * Caller must lock the mutex.
@@ -532,7 +533,7 @@ private:
 	/**
 	 * Caller must lock the mutex.
 	 */
-	bool PlayChunk() noexcept;
+	bool PlayChunk(std::unique_lock<Mutex> &lock) noexcept;
 
 	/**
 	 * Plays all remaining chunks, until the tail of the pipe has
@@ -546,14 +547,14 @@ private:
 	 * @return true if at least one chunk has been available,
 	 * false if the tail of the pipe was already reached
 	 */
-	bool InternalPlay() noexcept;
+	bool InternalPlay(std::unique_lock<Mutex> &lock) noexcept;
 
 	/**
 	 * Runs inside the OutputThread.
 	 * Caller must lock the mutex.
 	 * Handles exceptions.
 	 */
-	void InternalPause() noexcept;
+	void InternalPause(std::unique_lock<Mutex> &lock) noexcept;
 
 	/**
 	 * Runs inside the OutputThread.

src/output/Thread.cxx

@@ -208,14 +208,14 @@ AudioOutputControl::InternalCheckClose(bool drain) noexcept
  * was issued
  */
 inline bool
-AudioOutputControl::WaitForDelay() noexcept
+AudioOutputControl::WaitForDelay(std::unique_lock<Mutex> &lock) noexcept
 {
 	while (true) {
 		const auto delay = output->Delay();
 		if (delay <= std::chrono::steady_clock::duration::zero())
 			return true;
 
-		(void)wake_cond.wait_for(mutex, delay);
+		(void)wake_cond.wait_for(lock, delay);
 
 		if (command != Command::NONE)
 			return false;
@@ -234,7 +234,7 @@ try {
 }
 
 inline bool
-AudioOutputControl::PlayChunk() noexcept
+AudioOutputControl::PlayChunk(std::unique_lock<Mutex> &lock) noexcept
 {
 	// ensure pending tags are flushed in all cases
 	const auto *tag = source.ReadTag();
@@ -256,7 +256,7 @@ AudioOutputControl::PlayChunk() noexcept
 
 		if (skip_delay)
 			skip_delay = false;
-		else if (!WaitForDelay())
+		else if (!WaitForDelay(lock))
 			break;
 
 		size_t nbytes;
@@ -282,7 +282,7 @@ AudioOutputControl::PlayChunk() noexcept
 }
 
 inline bool
-AudioOutputControl::InternalPlay() noexcept
+AudioOutputControl::InternalPlay(std::unique_lock<Mutex> &lock) noexcept
 {
 	if (!FillSourceOrClose())
 		/* no chunk available */
@@ -311,7 +311,7 @@ AudioOutputControl::InternalPlay() noexcept
 			n = 0;
 		}
 
-		if (!PlayChunk())
+		if (!PlayChunk(lock))
 			break;
 	} while (FillSourceOrClose());
 
@@ -322,7 +322,7 @@ AudioOutputControl::InternalPlay() noexcept
 }
 
 inline void
-AudioOutputControl::InternalPause() noexcept
+AudioOutputControl::InternalPause(std::unique_lock<Mutex> &lock) noexcept
 {
 	{
 		const ScopeUnlock unlock(mutex);
@@ -334,7 +334,7 @@ AudioOutputControl::InternalPause() noexcept
 	CommandFinished();
 
 	do {
-		if (!WaitForDelay())
+		if (!WaitForDelay(lock))
 			break;
 
 		bool success;
@@ -448,7 +448,7 @@ AudioOutputControl::Task() noexcept
 				break;
 			}
 
-			InternalPause();
+			InternalPause(lock);
 			/* don't "break" here: this might cause
 			   Play() to be called when command==CLOSE
 			   ends the paused state - "continue" checks
@@ -472,7 +472,7 @@ AudioOutputControl::Task() noexcept
 				   have been invalidated by stopping
 				   the actual playback */
 				source.Cancel();
-				InternalPause();
+				InternalPause(lock);
 			} else {
 				InternalClose(false);
 				CommandFinished();
@@ -509,7 +509,7 @@ AudioOutputControl::Task() noexcept
 			return;
 		}
 
-		if (open && allow_play && InternalPlay())
+		if (open && allow_play && InternalPlay(lock))
 			/* don't wait for an event if there are more
 			   chunks in the pipe */
 			continue;