From 8d10aa7e80c81cd1ea63614addc506dd0939521a Mon Sep 17 00:00:00 2001
From: Christopher Snowhill <kode54@gmail.com>
Date: Sat, 25 Jun 2022 06:00:11 -0700
Subject: [PATCH] [Audio Output] Fix serious memory leakage

For one thing, the example code I followed was Swift and handled auto
releasing handles in the background, while Objective-C requires manual
handle reference management.

For two, there was no autoreleasepool around the block handling the
input audio chunks, which need to be released as they are pulled out and
disposed of. This also contributed to memory leakage.

Signed-off-by: Christopher Snowhill <kode54@gmail.com>
---
 Audio/Output/OutputAVFoundation.m | 45 ++++++++++++++++++++++++-------
 1 file changed, 35 insertions(+), 10 deletions(-)

diff --git a/Audio/Output/OutputAVFoundation.m b/Audio/Output/OutputAVFoundation.m
index d6b3b2621..84f122916 100644
--- a/Audio/Output/OutputAVFoundation.m
+++ b/Audio/Output/OutputAVFoundation.m
@@ -347,19 +347,23 @@ current_device_listener(AudioObjectID inObjectID, UInt32 inNumberAddresses, cons
 		if(stopping)
 			break;
 
-		while(!stopping && [audioRenderer isReadyForMoreMediaData]) {
-			CMSampleBufferRef bufferRef = [self makeSampleBuffer];
+		@autoreleasepool {
+			while(!stopping && [audioRenderer isReadyForMoreMediaData]) {
+				CMSampleBufferRef bufferRef = [self makeSampleBuffer];
 
-			if(bufferRef) {
-				CMTime chunkDuration = CMSampleBufferGetDuration(bufferRef);
+				if(bufferRef) {
+					CMTime chunkDuration = CMSampleBufferGetDuration(bufferRef);
 
-				outputPts = CMTimeAdd(outputPts, chunkDuration);
-				trackPts = CMTimeAdd(trackPts, chunkDuration);
+					outputPts = CMTimeAdd(outputPts, chunkDuration);
+					trackPts = CMTimeAdd(trackPts, chunkDuration);
 
-				[audioRenderer enqueueSampleBuffer:bufferRef];
-			} else {
-				stopFlush = YES;
-				break;
+					[audioRenderer enqueueSampleBuffer:bufferRef];
+
+					CFRelease(bufferRef);
+				} else {
+					stopFlush = YES;
+					break;
+				}
 			}
 		}
 
@@ -640,6 +644,11 @@ current_device_listener(AudioObjectID inObjectID, UInt32 inNumberAddresses, cons
 		layout.mChannelBitmap = streamChannelConfig;
 	}
 
+	if(audioFormatDescription) {
+		CFRelease(audioFormatDescription);
+		audioFormatDescription = NULL;
+	}
+
 	if(CMAudioFormatDescriptionCreate(kCFAllocatorDefault, &streamFormat, sizeof(layout), &layout, 0, NULL, NULL, &audioFormatDescription) != noErr) {
 		return;
 	}
@@ -674,8 +683,10 @@ current_device_listener(AudioObjectID inObjectID, UInt32 inNumberAddresses, cons
 
 	OSStatus err = CMAudioSampleBufferCreateReadyWithPacketDescriptions(kCFAllocatorDefault, blockBuffer, audioFormatDescription, samplesRendered, outputPts, nil, &sampleBuffer);
 	if(err != noErr) {
+		CFRelease(blockBuffer);
 		return nil;
 	}
+	CFRelease(blockBuffer);
 
 	return sampleBuffer;
 }
@@ -744,6 +755,7 @@ current_device_listener(AudioObjectID inObjectID, UInt32 inNumberAddresses, cons
 					status = AudioUnitRender(_eq, NULL, &timeStamp, 0, samplesRendered, ioData);
 
 					if(status != noErr) {
+						CFRelease(blockListBuffer);
 						return 0;
 					}
 
@@ -761,20 +773,27 @@ current_device_listener(AudioObjectID inObjectID, UInt32 inNumberAddresses, cons
 			status = CMBlockBufferCreateWithMemoryBlock(kCFAllocatorDefault, nil, dataByteSize, kCFAllocatorDefault, nil, 0, dataByteSize, kCMBlockBufferAssureMemoryNowFlag, &blockBuffer);
 
 			if(status != noErr || !blockBuffer) {
+				CFRelease(blockListBuffer);
 				return 0;
 			}
 
 			status = CMBlockBufferReplaceDataBytes(samplePtr, blockBuffer, 0, dataByteSize);
 
 			if(status != noErr) {
+				CFRelease(blockBuffer);
+				CFRelease(blockListBuffer);
 				return 0;
 			}
 
 			status = CMBlockBufferAppendBufferReference(blockListBuffer, blockBuffer, 0, CMBlockBufferGetDataLength(blockBuffer), 0);
 
 			if(status != noErr) {
+				CFRelease(blockBuffer);
+				CFRelease(blockListBuffer);
 				return 0;
 			}
+
+			CFRelease(blockBuffer);
 		}
 
 		if(i == 0) {
@@ -809,6 +828,8 @@ current_device_listener(AudioObjectID inObjectID, UInt32 inNumberAddresses, cons
 		stopCompleted = NO;
 		commandStop = NO;
 
+		audioFormatDescription = NULL;
+
 		running = NO;
 		stopping = NO;
 		stopped = NO;
@@ -1078,6 +1099,10 @@ current_device_listener(AudioObjectID inObjectID, UInt32 inNumberAddresses, cons
 				usleep(5000);
 			}
 		}
+		if(audioFormatDescription) {
+			CFRelease(audioFormatDescription);
+			audioFormatDescription = NULL;
+		}
 		if(_eq) {
 			[outputController endEqualizer:_eq];
 			if(eqInitialized) {