From a97ad12465996b7673ae05434cf82e6081c6a0c4 Mon Sep 17 00:00:00 2001
From: Xiaoming Shi <xiaomings@google.com>
Date: Sat, 25 Jul 2026 16:40:50 -0700
Subject: [PATCH] starboard: Fix unsafe integer in AudioTrack sink

Fix potential overflow and narrowing issues in AudioTrackAudioSink.
Change accumulated_written_frames, last_playback_head_position,
and playback_head_position to int64_t to prevent overflow after
long playback times (~12.4 hours at 48kHz).
Update GetFramesDurationUs to accept int64_t.

Bug: 511356295
TAG=agy
CONV=0d3a836a-08df-4860-a867-0f6affc85b25
---
 starboard/android/shared/audio_track_audio_sink_type.cc | 8 ++++----
 starboard/android/shared/audio_track_audio_sink_type.h  | 2 +-
 2 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/starboard/android/shared/audio_track_audio_sink_type.cc b/starboard/android/shared/audio_track_audio_sink_type.cc
index d9d180478b44..5f62b3b76d66 100644
--- a/starboard/android/shared/audio_track_audio_sink_type.cc
+++ b/starboard/android/shared/audio_track_audio_sink_type.cc
@@ -261,10 +261,10 @@ void AudioTrackAudioSink::AudioThreadFunc() {
 
   SB_LOG(INFO) << "AudioTrackAudioSink thread started.";
 
-  int accumulated_written_frames = 0;
+  int64_t accumulated_written_frames = 0;
   int64_t last_playback_head_event_at = -1;  // microseconds
 
-  int last_playback_head_position = 0;
+  int64_t last_playback_head_position = 0;
 
   bool release_frames_after_audio_starts = features::FeatureList::IsEnabled(
       features::kReleaseVideoFramesAfterAudioStarts);
@@ -284,7 +284,7 @@ void AudioTrackAudioSink::AudioThreadFunc() {
       continue;
     }
 
-    int playback_head_position = 0;
+    int64_t playback_head_position = 0;
     int64_t frames_consumed_at = 0;
     if (audio_track_->GetAndResetHasAudioDeviceChanged()) {
       SB_LOG(INFO) << "Audio device changed, raising a capability changed "
@@ -515,7 +515,7 @@ void AudioTrackAudioSink::ReportError(bool capability_changed,
   }
 }
 
-int64_t AudioTrackAudioSink::GetFramesDurationUs(int frames) const {
+int64_t AudioTrackAudioSink::GetFramesDurationUs(int64_t frames) const {
   return frames * 1'000'000LL / sampling_frequency_hz_;
 }
 
diff --git a/starboard/android/shared/audio_track_audio_sink_type.h b/starboard/android/shared/audio_track_audio_sink_type.h
index 5bfb2ccfe692..2344278fef83 100644
--- a/starboard/android/shared/audio_track_audio_sink_type.h
+++ b/starboard/android/shared/audio_track_audio_sink_type.h
@@ -169,7 +169,7 @@ class AudioTrackAudioSink : public SbAudioSinkImpl {
 
   void ReportError(bool capability_changed, const std::string& error_message);
 
-  int64_t GetFramesDurationUs(int frames) const;
+  int64_t GetFramesDurationUs(int64_t frames) const;
 
   const raw_ptr<Type> type_;
   const int channels_;