From c1cd268532f8aa1e6869514569eb077cbc5ce56c Mon Sep 17 00:00:00 2001
From: derrod <dennis@obsproject.com>
Date: Tue, 1 Aug 2023 09:02:04 +0200
Subject: [PATCH] UI: Fix matching FFmpeg formats/codecs

---
 UI/ffmpeg-utils.hpp          | 27 ++++++++++++++++++++++++---
 UI/window-basic-settings.cpp |  2 +-
 2 files changed, 25 insertions(+), 4 deletions(-)

diff --git a/UI/ffmpeg-utils.hpp b/UI/ffmpeg-utils.hpp
index 5a5eeadf7..55bfd5c43 100644
--- a/UI/ffmpeg-utils.hpp
+++ b/UI/ffmpeg-utils.hpp
@@ -28,6 +28,25 @@ extern "C" {
 
 enum FFmpegCodecType { AUDIO, VIDEO, UNKNOWN };
 
+/* This needs to handle a few special cases due to how the format is used in the UI:
+ * - strequal(nullptr, "") must be true
+ * - strequal("", nullptr) must be true
+ * - strequal(nullptr, nullptr) must be true
+ */
+static bool strequal(const char *a, const char *b)
+{
+	if (!a && !b)
+		return true;
+	if (!a && *b == 0)
+		return true;
+	if (!b && *a == 0)
+		return true;
+	if (!a || !b)
+		return false;
+
+	return strcmp(a, b) == 0;
+}
+
 struct FFmpegFormat {
 	const char *name;
 	const char *long_name;
@@ -46,9 +65,10 @@ struct FFmpegFormat {
 
 	bool operator==(const FFmpegFormat &format) const
 	{
-		if (strcmp(name, format.name) != 0)
+		if (!strequal(name, format.name))
 			return false;
-		return strcmp(mime_type, format.mime_type) != 0;
+
+		return strequal(mime_type, format.mime_type);
 	}
 };
 Q_DECLARE_METATYPE(FFmpegFormat)
@@ -69,7 +89,8 @@ struct FFmpegCodec {
 	{
 		if (id != codec.id)
 			return false;
-		return strcmp(name, codec.name) != 0;
+
+		return strequal(name, codec.name);
 	}
 };
 Q_DECLARE_METATYPE(FFmpegCodec)
diff --git a/UI/window-basic-settings.cpp b/UI/window-basic-settings.cpp
index dc9f051fc..53fc7d447 100644
--- a/UI/window-basic-settings.cpp
+++ b/UI/window-basic-settings.cpp
@@ -2238,7 +2238,7 @@ void OBSBasicSettings::LoadAdvOutputRecordingEncoderProperties()
 static void SelectFormat(QComboBox *combo, const char *name,
 			 const char *mimeType)
 {
-	FFmpegFormat format{name, mimeType};
+	FFmpegFormat format{name, nullptr, mimeType};
 
 	for (int i = 0; i < combo->count(); i++) {
 		QVariant v = combo->itemData(i);