From 0737e57898d2ea09c84a6bcc4d946ac384dcd1b2 Mon Sep 17 00:00:00 2001
From: Paul Adenot <paul@paul.cx>
Date: Thu, 4 Apr 2024 15:02:31 +0000
Subject: [PATCH] Bug 1860492 - Add a pref to disable Theora playback, disable
 it on Nightly. r=media-playback-reviewers,alwu

Differential Revision: https://phabricator.services.mozilla.com/D204052
---
 dom/media/ogg/OggDecoder.cpp                         | 10 +++++++---
 .../platforms/agnostic/AgnosticDecoderModule.cpp     | 12 ++++++++----
 modules/libpref/init/StaticPrefList.yaml             |  6 ++++++
 3 files changed, 21 insertions(+), 7 deletions(-)

diff --git a/dom/media/ogg/OggDecoder.cpp b/dom/media/ogg/OggDecoder.cpp
index 5f6d61f694c2..1bacafcf3e76 100644
--- a/dom/media/ogg/OggDecoder.cpp
+++ b/dom/media/ogg/OggDecoder.cpp
@@ -24,7 +24,10 @@ bool OggDecoder::IsSupportedType(const MediaContainerType& aContainerType) {
     return false;
   }
 
-  const bool isOggVideo = (aContainerType.Type() != MEDIAMIMETYPE(AUDIO_OGG));
+  const bool isOggVideo = (aContainerType.Type() == MEDIAMIMETYPE(VIDEO_OGG));
+  if (isOggVideo && !StaticPrefs::media_theora_enabled()) {
+    return false;
+  }
 
   const MediaCodecs& codecs = aContainerType.ExtendedType().Codecs();
   if (codecs.IsEmpty()) {
@@ -40,8 +43,9 @@ bool OggDecoder::IsSupportedType(const MediaContainerType& aContainerType) {
     }
     // Note: Only accept Theora in a video container type, not in an audio
     // container type.
-    if (isOggVideo && codec.EqualsLiteral("theora")) {
-      continue;
+    if (aContainerType.Type() != MEDIAMIMETYPE(AUDIO_OGG) &&
+        codec.EqualsLiteral("theora")) {
+      return StaticPrefs::media_theora_enabled();
     }
     // Some unsupported codec.
     return false;
diff --git a/dom/media/platforms/agnostic/AgnosticDecoderModule.cpp b/dom/media/platforms/agnostic/AgnosticDecoderModule.cpp
index 7bdc30b43248..753dee02381f 100644
--- a/dom/media/platforms/agnostic/AgnosticDecoderModule.cpp
+++ b/dom/media/platforms/agnostic/AgnosticDecoderModule.cpp
@@ -36,8 +36,9 @@ static bool IsAvailableInDefault(DecoderType type) {
     case DecoderType::AV1:
       return StaticPrefs::media_av1_enabled();
 #endif
-    case DecoderType::Opus:
     case DecoderType::Theora:
+      return StaticPrefs::media_theora_enabled();
+    case DecoderType::Opus:
     case DecoderType::Vorbis:
     case DecoderType::VPX:
     case DecoderType::Wave:
@@ -56,7 +57,8 @@ static bool IsAvailableInRdd(DecoderType type) {
     case DecoderType::Opus:
       return StaticPrefs::media_rdd_opus_enabled();
     case DecoderType::Theora:
-      return StaticPrefs::media_rdd_theora_enabled();
+      return StaticPrefs::media_rdd_theora_enabled() &&
+             StaticPrefs::media_theora_enabled();
     case DecoderType::Vorbis:
 #if defined(__MINGW32__)
       // If this is a MinGW build we need to force AgnosticDecoderModule to
@@ -129,7 +131,8 @@ media::DecodeSupportSet AgnosticDecoderModule::Supports(
       (AOMDecoder::IsAV1(mimeType) && IsAvailable(DecoderType::AV1)) ||
 #endif
       (VPXDecoder::IsVPX(mimeType) && IsAvailable(DecoderType::VPX)) ||
-      (TheoraDecoder::IsTheora(mimeType) && IsAvailable(DecoderType::Theora));
+      (TheoraDecoder::IsTheora(mimeType) && IsAvailable(DecoderType::Theora) &&
+       StaticPrefs::media_theora_enabled());
   MOZ_LOG(sPDMLog, LogLevel::Debug,
           ("Agnostic decoder %s requested type '%s'",
            supports ? "supports" : "rejects", mimeType.BeginReading()));
@@ -164,7 +167,8 @@ already_AddRefed<MediaDataDecoder> AgnosticDecoderModule::CreateVideoDecoder(
     }
   }
 #endif
-  else if (TheoraDecoder::IsTheora(aParams.mConfig.mMimeType)) {
+  else if (TheoraDecoder::IsTheora(aParams.mConfig.mMimeType) &&
+           StaticPrefs::media_theora_enabled()) {
     m = new TheoraDecoder(aParams);
   }
 
diff --git a/modules/libpref/init/StaticPrefList.yaml b/modules/libpref/init/StaticPrefList.yaml
index 9ba3d123fae9..9d6cfd7f919e 100644
--- a/modules/libpref/init/StaticPrefList.yaml
+++ b/modules/libpref/init/StaticPrefList.yaml
@@ -11183,6 +11183,12 @@
     mirror: always
 #endif
 
+# Bug 1860492 - Deprecate and remove theora
+-  name: media.theora.enabled
+   type: RelaxedAtomicBool
+   value: @IS_NOT_NIGHTLY_BUILD@
+   mirror: always
+
 #---------------------------------------------------------------------------
 # Prefs starting with "memory."
 #---------------------------------------------------------------------------