From 801d7e8d1e6e75a7aa123c4685f8288383c8b3af Mon Sep 17 00:00:00 2001
From: Iliyas Jorio <iliyas@jor.io>
Date: Sun, 15 May 2022 10:47:52 +0200
Subject: [PATCH] Preprocess sound resource: Convert big-endian raw PCM to
 little-endian

---
 src/SoundFormats/SoundFormats.cpp | 14 +++++++++++++-
 1 file changed, 13 insertions(+), 1 deletion(-)

diff --git a/src/SoundFormats/SoundFormats.cpp b/src/SoundFormats/SoundFormats.cpp
index ac5416c..2054aeb 100644
--- a/src/SoundFormats/SoundFormats.cpp
+++ b/src/SoundFormats/SoundFormats.cpp
@@ -274,11 +274,23 @@ Boolean Pomme_DecompressSoundResource(SndListHandle* sndHandlePtr, long* offsetT
 
 	if (!inInfo.isCompressed)
 	{
-		// Raw big-endian PCM
+		// Raw PCM
 		if (inInfo.decompressedLength != inInfo.compressedLength)
 			throw std::runtime_error("decompressedLength != compressedLength???");
 
 		memcpy(outDataStart, inDataStart, inInfo.decompressedLength);
+
+		// If it's big endian, swap the bytes
+		int bytesPerSample = inInfo.codecBitDepth / 8;
+		if (inInfo.bigEndian && bytesPerSample > 1)
+		{
+			int nIntegers = inInfo.decompressedLength / bytesPerSample;
+			if (inInfo.decompressedLength != nIntegers * bytesPerSample)
+				throw std::runtime_error("unexpected big-endian raw PCM decompressed length");
+
+			ByteswapInts(bytesPerSample, nIntegers, outDataStart);
+			outInfo.bigEndian = false;
+		}
 	}
 	else
 	{