From: bones_was_here <bones_was_here@xonotic.au>
Date: Sun, 25 Aug 2024 15:34:33 +0000 (+1000)
Subject: snd: don't lock the device while we already have the lock
X-Git-Url: https://git.rm.cloudns.org/?a=commitdiff_plain;h=6fac3b2c6a5610437ba0f6d4b460879287b6487d;p=xonotic%2Fdarkplaces.git

snd: don't lock the device while we already have the lock

while also having a comment about how we don't need to do it...

Signed-off-by: bones_was_here <bones_was_here@xonotic.au>
---

diff --git a/snd_sdl.c b/snd_sdl.c
index e93d3021..3752dcde 100644
--- a/snd_sdl.c
+++ b/snd_sdl.c
@@ -29,7 +29,8 @@ static unsigned int sdlaudiotime = 0;
 static int audio_device = 0;
 
 
-// Note: SDL calls SDL_LockAudio() right before this function, so no need to lock the audio data here
+// This function is called when the audio device needs more data.
+// Note: SDL obtains the device lock before calling this function, no need to lock it here.
 static void Buffer_Callback (void *userdata, Uint8 *stream, int len)
 {
 	unsigned int factor, RequestedFrames, MaxFrames, FrameCount;
@@ -41,57 +42,51 @@ static void Buffer_Callback (void *userdata, Uint8 *stream, int len)
 
 	RequestedFrames = (unsigned int)len / factor;
 
-	if (SndSys_LockRenderBuffer())
+	if (snd_usethreadedmixing)
 	{
-		if (snd_usethreadedmixing)
-		{
-			S_MixToBuffer(stream, RequestedFrames);
-			if (snd_blocked)
-				memset(stream, snd_renderbuffer->format.width == 1 ? 0x80 : 0, len);
-			SndSys_UnlockRenderBuffer();
-			return;
-		}
-
-		// Transfert up to a chunk of samples from snd_renderbuffer to stream
-		MaxFrames = snd_renderbuffer->endframe - snd_renderbuffer->startframe;
-		if (MaxFrames > RequestedFrames)
-			FrameCount = RequestedFrames;
-		else
-			FrameCount = MaxFrames;
-		StartOffset = snd_renderbuffer->startframe % snd_renderbuffer->maxframes;
-		EndOffset = (snd_renderbuffer->startframe + FrameCount) % snd_renderbuffer->maxframes;
-		if (StartOffset > EndOffset)  // if the buffer wraps
-		{
-			unsigned int PartialLength1, PartialLength2;
-
-			PartialLength1 = (snd_renderbuffer->maxframes - StartOffset) * factor;
-			memcpy(stream, &snd_renderbuffer->ring[StartOffset * factor], PartialLength1);
-
-			PartialLength2 = FrameCount * factor - PartialLength1;
-			memcpy(&stream[PartialLength1], &snd_renderbuffer->ring[0], PartialLength2);
-
-			// As of SDL 2.0 buffer needs to be fully initialized, so fill leftover part with silence
-			// FIXME this is another place that assumes 8bit is always unsigned and others always signed
-			memset(&stream[PartialLength1 + PartialLength2], snd_renderbuffer->format.width == 1 ? 0x80 : 0, len - (PartialLength1 + PartialLength2));
-		}
-		else
-		{
-			memcpy(stream, &snd_renderbuffer->ring[StartOffset * factor], FrameCount * factor);
-
-			// As of SDL 2.0 buffer needs to be fully initialized, so fill leftover part with silence
-			// FIXME this is another place that assumes 8bit is always unsigned and others always signed
-			memset(&stream[FrameCount * factor], snd_renderbuffer->format.width == 1 ? 0x80 : 0, len - (FrameCount * factor));
-		}
-
-		snd_renderbuffer->startframe += FrameCount;
-
-		if (FrameCount < RequestedFrames && developer_insane.integer && vid_activewindow)
-			Con_DPrintf("SDL sound: %u sample frames missing\n", RequestedFrames - FrameCount);
-
-		sdlaudiotime += RequestedFrames;
-
-		SndSys_UnlockRenderBuffer();
+		S_MixToBuffer(stream, RequestedFrames);
+		if (snd_blocked)
+			memset(stream, snd_renderbuffer->format.width == 1 ? 0x80 : 0, len);
+		return;
 	}
+
+	// Transfert up to a chunk of samples from snd_renderbuffer to stream
+	MaxFrames = snd_renderbuffer->endframe - snd_renderbuffer->startframe;
+	if (MaxFrames > RequestedFrames)
+		FrameCount = RequestedFrames;
+	else
+		FrameCount = MaxFrames;
+	StartOffset = snd_renderbuffer->startframe % snd_renderbuffer->maxframes;
+	EndOffset = (snd_renderbuffer->startframe + FrameCount) % snd_renderbuffer->maxframes;
+	if (StartOffset > EndOffset)  // if the buffer wraps
+	{
+		unsigned int PartialLength1, PartialLength2;
+
+		PartialLength1 = (snd_renderbuffer->maxframes - StartOffset) * factor;
+		memcpy(stream, &snd_renderbuffer->ring[StartOffset * factor], PartialLength1);
+
+		PartialLength2 = FrameCount * factor - PartialLength1;
+		memcpy(&stream[PartialLength1], &snd_renderbuffer->ring[0], PartialLength2);
+
+		// As of SDL 2.0 buffer needs to be fully initialized, so fill leftover part with silence
+		// FIXME this is another place that assumes 8bit is always unsigned and others always signed
+		memset(&stream[PartialLength1 + PartialLength2], snd_renderbuffer->format.width == 1 ? 0x80 : 0, len - (PartialLength1 + PartialLength2));
+	}
+	else
+	{
+		memcpy(stream, &snd_renderbuffer->ring[StartOffset * factor], FrameCount * factor);
+
+		// As of SDL 2.0 buffer needs to be fully initialized, so fill leftover part with silence
+		// FIXME this is another place that assumes 8bit is always unsigned and others always signed
+		memset(&stream[FrameCount * factor], snd_renderbuffer->format.width == 1 ? 0x80 : 0, len - (FrameCount * factor));
+	}
+
+	snd_renderbuffer->startframe += FrameCount;
+
+	if (FrameCount < RequestedFrames && developer_insane.integer && vid_activewindow)
+		Con_DPrintf("SDL sound: %u sample frames missing\n", RequestedFrames - FrameCount);
+
+	sdlaudiotime += RequestedFrames;
 }