Constraint: SRS-163 requires Android back to be handled by the shell/platform layer, and the Dart service existed but was not wired into the live app.
Rejected: Leave BackIntentService test-only and unwired | System back would bypass app policy on Android.
Confidence: medium
Scope-risk: narrow
Directive: Keep back-intent probe state in sync with every new dialog or pushed route added to the Flutter shell.
Tested: dart format apps/chanora_flutter/lib/main.dart; flutter analyze lib/main.dart test/services/back_intent_service_test.dart; flutter test test/services/back_intent_service_test.dart
Not-tested: Manual Android device back-navigation smoke test
Closes DEC-032. Restores the canonical Android ABI set
{arm64-v8a, armeabi-v7a, x86_64} per SDD-073 item 4 / SDD-118 item 3.
Root cause was the audiopus_sys + cmake-rs + NDK toolchain-file gap:
cargo-ndk 4.x sets ANDROID_ABI / ANDROID_PLATFORM as env vars per
invocation, but upstream cmake-rs 0.x does not forward them to the
child cmake invocation as -D variables, so armeabi-v7a and x86_64
configure steps fell through to the toolchain-file default and
failed to build.
Fix:
- Cargo.toml: add a workspace [patch.crates-io] stanza pinning the
cmake crate to fork pr2502/cmake-rs @ commit
bdad5edc569d82151922c5c6c4685b1563f12aa1 (branch android-build),
which carries cmake-rs PR #257
(https://github.com/rust-lang/cmake-rs/pull/257). The patch is a
9-line addition that forwards ANDROID_ABI and ANDROID_PLATFORM
from the env to the child cmake as -D variables.
- Cargo.lock: regenerated by 'cargo update -p cmake'; the lone
cmake entry now points at the fork rev.
- apps/chanora_flutter/android/app/build.gradle.kts: restore
abiFilters to {arm64-v8a, armeabi-v7a, x86_64}; remove the
TODO(x86_64/armv7 follow-up) comment.
- docs/governance/product-decision-register.md: mark DEC-032 as
Resolved (2026-05-18) with the resolution mechanism, update the
§3 / §7 rows, and append a 0.9.8.1 change-history entry.
Verification (host: Linux):
cargo update -p cmake -> pulled fork rev
cargo check --workspace --all-targets -> PASS
cargo test --workspace -> PASS (no regressions)
cargo ndk --platform 28 -t arm64-v8a build -p chanora_bridge -> PASS
cargo ndk --platform 28 -t armeabi-v7a build -p chanora_bridge -> PASS
cargo ndk --platform 28 -t x86_64 build -p chanora_bridge -> PASS
Upstream tracking: re-evaluate the [patch.crates-io] override once
cmake-rs PR #257 merges and a fresh cmake release lands on
crates.io; at that point switch to a plain dep bump and remove the
override.
Resolve the macOS half of the SDD-119 item 3 single-source-of-truth follow-up. The chanora_bridge cdylib macOS deployment-target floor ('10.15') was previously hard-coded at 7 sites across Podfile and chanora_bridge.podspec; this commit collapses them to a single Ruby constant declaration in a new SoT file.
Selected Option B (Ruby constant) over Option A (.xcconfig — rejected because the podspec prepare_command runs before any xcconfig is applied) and Option C (versioned text file — rejected as overkill given both consumers are already Ruby). Realizes SAD-087(a)'s 'single macOS build-configuration location' mandate.
Out of scope: the pbxproj 'MACOSX_DEPLOYMENT_TARGET = 10.15' lines (565/666/717) belong to the PBXProject default config and are independently overridden to '11.0' at the Runner PBXNativeTarget level; they are the Runner app's floor, not the bridge cdylib's floor. The iOS half (IPHONEOS_DEPLOYMENT_TARGET=13.0) remains an open follow-up.
Files: new apps/chanora_flutter/macos/macos_deployment_target.rb (MACOS_BRIDGE_DEPLOYMENT_TARGET = '10.15'.freeze); Podfile + chanora_bridge.podspec require_relative the constant and consume it at 7 sites; docs/architecture/sdd.md SDD-119 item 3 rewritten + Notes bullet updated + v0.9.17 changelog entry.
Dart consumer for the Android permission state pipeline. New
AndroidPermissionsService listens on the app.chanora/android_permissions
MethodChannel and exposes a ValueListenable for the UI. The voice-join
flow in main.dart calls ensureRecordAudio() before rust.voiceJoin and
clamps to listen-only via setHardMute on denial. A non-modal banner
above the VoiceBar surfaces the Grant / Open Settings action depending
on whether the state is Denied or PermanentlyDenied. On non-Android
hosts the service short-circuits to granted; the banner is never built.
Also adds the BackIntentService Dart consumer (back_intent_policy +
back_intent_service) which the Kotlin BackIntentBridge invokes via
MethodChannel for deterministic route-pop ordering.
Trace: SDD-028, SDD-106, SRS-163, SRS-209.
Android P0 platform shell:
- ChanoraApplication: early System.loadLibrary("c++_shared") +
System.loadLibrary("chanora_bridge") so JNI is hot before
MainActivity.onCreate.
- MainActivity: configureFlutterEngine + onResume/onDestroy wiring
for BackIntentBridge and AndroidPermissionRequester; publishes
permission-state changes through both the MethodChannel (Dart UI)
and the JNI hook (Rust audio engine).
- AndroidVoiceForegroundService: microphone-type foreground service
with notification channel chanora.voice.session per SDD-107.
- AndroidPermissionRequester: RECORD_AUDIO state machine with
persisted "has-ever-requested" flag so PermanentlyDenied is
correctly distinguished from never-asked across cold launches.
- BackIntentBridge: API 33+ OnBackInvokedCallback + pre-33
OnBackPressedDispatcher with deterministic Dart-side policy.
- MethodChannels: centralized constants for app.chanora/*.
- build.gradle.kts: SDD-118 Gradle automation that auto-builds the
Rust cdylib via cargo-ndk with per-ABI Exec tasks, minimal-env
isolation, CMAKE_TOOLCHAIN_FILE pinning, libc++_shared.so staging,
release-inspection assertion. abiFilters temporarily reduced to
arm64-v8a only per DEC-032 (multi-ABI restoration pending).
- AndroidManifest.xml: INTERNET, RECORD_AUDIO, FOREGROUND_SERVICE,
FOREGROUND_SERVICE_MICROPHONE, POST_NOTIFICATIONS,
MODIFY_AUDIO_SETTINGS, BLUETOOTH_CONNECT permissions; service
declaration with foregroundServiceType=microphone.
- proguard-rules.pro: keep rules for JNI native methods + Flutter
plugin entry points + FRB bindings.
Trace: SDD-073, SDD-105, SDD-106, SDD-107, SDD-108, SDD-110, SDD-118,
SRS-111, SRS-119, SRS-163, SRS-187, SRS-209, SRS-215.
Per SDD-106 §5 add BridgeEvent::PermissionState{permission, state}
with the PermissionStateKind enum (Granted, Denied, PermanentlyDenied,
Unknown). The Kotlin side publishes mid-session permission changes
through a new JNI entry point Java_app_chanora_chanora_1flutter
_MainActivity_publishPermissionState routed by the new
permission_jni.rs module; the Rust audio engine subscribes and
authoritatively clamps the transmit gate (see SDD-106 §6).
Adds crates/chanora_bridge/build.rs to emit
cargo:rustc-link-lib=dylib=c++_shared on Android so libchanora_bridge
.so carries DT_NEEDED libc++_shared.so; this is required by Android
API 24+ per-library linker namespaces to resolve __cxa_pure_virtual
and friends at System.loadLibrary time.
Includes the FRB-regenerated Dart counterparts so each commit is
independently buildable.
Trace: SDD-105, SDD-106 §5, SDD-118 item 6 (extended).
Debug and Profile had ENABLE_OUTGOING_NETWORK_CONNECTIONS = NO which
blocked outbound TCP. All three configs now have:
- ENABLE_HARDENED_RUNTIME = YES
- ENABLE_OUTGOING_NETWORK_CONNECTIONS = YES
This was the root cause of the 'Operation not permitted' connection
failure on macOS Sequoia.
macOS:
- Transparent title bar with hidden title, full-size content view
- macOS: inline Row header (no AppBar) with 56px traffic-light pad
- Other platforms: standard Material AppBar unchanged
- App name 'Chanora' in CFBundleName/CFBundleDisplayName (iOS + macOS)
- NSLocalNetworkUsageDescription added to both platforms
Linux:
- tools/build-linux.sh: builds Rust .so + Flutter bundle + tarball
- Verifies GTK3, libopus dev headers, Rust target
- Copies libchanora_bridge.so into bundle/lib/
Required for local network privacy prompt on macOS 15+ and iOS 14+.
App appears in System Settings → Local Network after connecting to a
LAN server. Internet-hosted servers only need network.client entitlement.
When macOS denies network access (PermissionDenied), show a localized
dialog explaining how to grant permission in System Settings, with
an 'Open System Settings' button that opens directly to the Local
Network privacy pane.
Also adds author info (Edison Jwa) to About dialog and moves
diagnostics button from AppBar into About dialog.
The ring-buffer architecture (rc.8+73..+74) was making playback
strictly worse. Diagnostic data at +74 conclusively showed:
* Producer task ran perfectly at 50 Hz (250 ticks per 5 s).
* AudioHandler returned silence on 65-84% of fill_buffer calls
even when window_peak_f32 reached 0.98 (full-scale audio).
* Ring buffer never accumulated beyond 30 ms because consumer
(VPIO render callback at 43.5 Hz, ~1440 samples per call)
drained samples faster than the 50 Hz producer could push
them, in net effect.
The producer drained AudioHandler at 50 Hz \u2014 slightly faster
than iOS VPIO actually consumes audio. Each fill_buffer call
asked for 20 ms but adjacent Opus packets hadn't arrived yet, so
fill_buffer returned mostly silence. Linux/SDL's same pattern
works because SDL calls fill_buffer at EXACTLY the device
callback rate (50 Hz = 20 ms per buffer); the rates match.
Fix: revert to direct fill_buffer call from the render callback
(the SDL pattern in tsclientlib's own reference example at
tsclientlib/examples/audio_utils/ts_to_audio.rs). The render
callback now:
1. Resizes scratch_stereo Vec to 2 * num_frames f32 if needed
2. Zeros the live slice (fill_buffer is additive, not clearing)
3. Locks AudioHandler, calls fill_buffer(scratch_stereo)
4. Downmixes L+R -> mono i16 with master gain into out[]
5. Applies output_muted bypass
6. Tracks peak_out + audio/silence ratios for diagnostic
The closure owns scratch_stereo across callbacks for stable
allocation. Same memory model as Linux/SDL.
Removed:
* tokio::spawn producer task
* rtrb dep + RingBuffer<i16> + Producer/Consumer split
* tokio::sync::oneshot shutdown channel
* producer_shutdown_tx field on IosVoiceUnit struct
* RING_BUFFER_SAMPLES / PRODUCER_TICK_MS constants
* Producer-side diagnostic counters
Diagnostic kept: cb / num_frames / frames_changes /
callbacks_with_audio / callbacks_with_silence / peak_out_i16 /
gain. Logged every 100 callbacks.
The choppy / clicks symptom is independent of the buffer
architecture \u2014 it's whatever AudioHandler is doing on iOS
that's different from Linux. Next investigation step is to
either (a) switch from VPIO to RemoteIO unit (lose Apple's
voice processing entirely), or (b) understand why AudioHandler
returns silence so often on iOS-arrival packet timing patterns.
Build counter 74 -> 75.
External reviewer correctly identified that the +73 ring-buffer
commit didn't fix the symptom but the architecture is still
right. We need to distinguish two possible causes:
(a) Producer task isn't running (or running too rarely) so
ring stays underfilled.
(b) Producer IS running but fill_buffer returns zeros most of
the time (AudioHandler stuck in buffering_samples state
or no packets reaching it).
The +73 render-side diagnostic was insufficient: we logged
underruns + peak_out_i16 but not what the producer was
actually pushing. This commit adds producer-side metrics
rolled up every 5 s (250 ticks at 20 ms):
Producer task:
producer_ticks : timer firings (= ~250 per 5 s window;
fewer = tokio scheduler stalled)
produced_chunks : pushes into ring (= ticks - drops)
fill_buffer_calls : AudioHandler queries
fill_buffer_zero_returns : ticks where scratch came back all
zeros (no decoded content to play)
ring_full_drops : ticks where ring was full and we
skipped the push
ring_min/max_samples : depth envelope across window
ring_min/max_ms : same in milliseconds
window_peak_f32 : max scratch sample across window
window_rms_f32 : RMS of all scratch samples across
window
Render callback (per-100-callback as before, plus new fields):
ring_avail_before : Consumer::slots() before this read
(= how many samples were sitting in
the ring at callback entry)
read_frames : samples successfully popped
zero_filled : samples zero-filled because ring
was empty (= num_frames - read_frames)
underruns / underrun_samples / peak_out_i16 / clip_count_i16
: as before
Reading the next iteration's log:
If producer_ticks << 250 per 5 s window:
tokio scheduler isn't running the task fast enough.
Move producer to its own dedicated runtime, or use
std::thread + std::sync::mpsc + std::thread::sleep
instead of tokio.
If producer_ticks ~= 250 AND fill_buffer_zero_returns is
high (most ticks return silence):
AudioHandler isn't decoding packets fast enough OR is
stuck buffering. Bug is upstream in protocol layer
packet delivery or AudioHandler's jitter state machine.
The ring buffer architecture cannot fix this.
If producer_ticks ~= 250 AND fill_buffer_zero_returns is
low AND ring_min_ms stays >100ms AND underruns are low BUT
consumer's peak_out_i16 is still 0:
Something is wrong between push and pop. Lock-free
ring corruption, or wrong stride.
Pure diagnostic. No behavioural change beyond the logging.
Producer scratch envelope scan is O(scratch.len()) = 1920
samples per 20 ms tick = ~96k iterations/sec on the audio
producer thread \u2014 negligible CPU.
Build counter 73 -> 74.
User confirmed at +72 the symptom is 'voice + constant clicks +
choppy fragments'. The diagnostic data conclusively pointed to
iOS VPIO render-callback timing as the cause:
* frames_changes=60+ per 100 callbacks at cb>=1800
iOS keeps switching num_frames between 960 and 1104
on roughly 60% of callbacks
* peak_out_i16 is sensible (2500-16870, never clipping)
when AudioHandler returns content
* input_was_zero=true on most callbacks during active speech
AudioHandler keeps entering buffering_samples state
The cause: previous render callback called fill_buffer
synchronously every iOS audio thread invocation. With iOS
calling at irregular rates with irregular sizes, AudioHandler's
jitter buffer (sized around 20 ms Opus frames) cannot satisfy
arbitrary-sized requests and falls back to returning silence
(&[] empty slice) on misaligned reads. The silent gaps in the
middle of the output buffer create discontinuities = audible
clicks; the missing-tail content produces choppy fragments.
Fix (architectural): decouple the AudioHandler decoder from the
VPIO render callback via a lock-free SPSC ring buffer.
Producer (tokio task, 50 Hz):
every 20 ms:
fill_buffer(scratch_stereo_f32, 1920 = 20 ms stereo)
downmix L+R -> mono i16 (960 samples)
ring_buffer.push_slice(mono_i16)
Consumer (VPIO render callback, iOS audio thread):
every callback:
pop num_frames samples from ring buffer into out
zero-fill tail on underrun
Why it works:
* Producer always asks AudioHandler for a stable 20 ms chunk
(perfectly aligned with internal Opus frame size). No more
buffering_samples false-triggers.
* Consumer pulls whatever iOS asks for whenever iOS schedules
it; ring buffer's 200 ms depth absorbs the callback jitter.
* This is the standard pattern every production VoIP audio
engine uses (WebRTC, Discord, FaceTime) to bridge bursty
Opus decoders to bursty platform audio callbacks.
Implementation:
* New dep: rtrb 0.3.4 (RustAudio realtime-safe SPSC ring
buffer, 6.8M downloads, lock-free push/pop with no
allocation on the audio thread).
* RING_BUFFER_SAMPLES = 9600 (200 ms mono i16 at 48 kHz).
Sized for 10x producer ticks of headroom.
* PRODUCER_TICK_MS = 20 (matches Opus 50 Hz packet rate).
set_missed_tick_behavior(Skip) to avoid burst catch-up on
runtime stalls.
* Producer task spawned in IosVoiceUnit::start, shutdown
via tokio::oneshot when IosVoiceUnit drops.
* Render callback is now just: pop into out, zero-fill tail,
apply mute then gain.
* Gain applied CONSUMER-side so user volume changes take
effect within one callback (<= 200 ms latency).
* Underrun diagnostics: count underrun callbacks + total
zero-filled samples, log every 100 callbacks.
Threading + safety:
* rtrb is lock-free SPSC. Audio thread never blocks.
* Producer can block briefly on Arc<Mutex<AudioHandler>>
contention with the inbound forwarder (handle_packet), but
not with the audio thread.
* Producer task is owned by tokio runtime; explicit shutdown
channel ensures it exits when the engine stops.
Build verify:
* Linux host: cargo check clean in 4.06s (downloads rtrb 0.3.4).
* iOS Mac: cargo check clean in 2.14s.
Build counter 72 -> 73.
External code review pushed back on the 'iPhone speaker hardware
distortion' hypothesis and pointed out we need more than just
peak measurements. The reviewer's checklist:
* peak_i16
* rms_i16
* num_clipped_samples (abs >= 32767)
* zero_fill_count / underrun_count
* callback_frame_count variability
* decoded_packet_duration_ms
* input_was_zero
* actual ASBD / actual sample rate
The format diagnostics at +71 already showed iOS honoured
48 kHz Int16 mono on both buses and that .default mode +
.defaultToSpeaker routed to the speaker correctly with
outputVolume=0.45. So format + route are confirmed correct.
The remaining mystery is WHY 'loud but distorted' \u2014 we need
sample-level metrics to isolate where in the pipeline the
breakage occurs.
This commit instruments the VPIO render callback with:
* num_frames + frames_changes : detects iOS re-negotiating
buffer size between callbacks
(which would imply jitter the
fixed scratch_stereo Vec can't
absorb cleanly).
* peak_stereo + rms_stereo : characterises AudioHandler's
output BEFORE our downmix.
Distinguishes 'real audio
arriving' from 'silence'.
* peak_out_i16 + clip_count : measures what we hand VPIO.
clip_count > 0 means we're
clipping at our boundary even
with gain=1.0 \u2014 indicates
upstream is over-driven.
* input_was_zero : explicit silence/no-talker
indicator separate from peak=0
which could mean tiny content
rounded to 0.
Reviewer's preferred diagnostic path is to dump PCM to file
and play with ffplay externally; that's iOS-impractical
without a shared filesystem path the user can extract via
Files.app. Instead we sample the same metrics in-callback at
~2 Hz which gives us the same information at run time.
Pure diagnostic. No behavioural change. Counters live in the
FnMut closure so the audio thread cost is one branch +
counter increment per callback, plus a one-pass RMS sum +
peak scan every 100 callbacks.
Build counter 71 -> 72.
Reviewer also recommended a headphone test in parallel \u2014
that will be done by the user (out-of-band) at the next
test cycle to determine whether the symptom changes when
audio leaves the speaker path.
Per external review (helpful checklist from ChatGPT-style analysis
pointing out we never verified that iOS actually accepted our
preferred sample rate / channels / format): preferredSampleRate
and preferredIOBufferDuration are HINTS, not guarantees. iOS may
substitute its own values if the hardware can't satisfy our
preference. If VPIO is running at 44.1 kHz Float32 stereo while
our render callback writes 48 kHz Int16 mono into the buffer,
the symptoms would match what user reports (broken playback,
pitch shifted, severe distortion) and our previous diagnostics
wouldn't catch it because they only sampled signal-level metrics.
This commit adds two diagnostic emissions to verify:
1. AppDelegate.swift::activateAudioSession: after setActive
succeeds, log the ACTUAL session state \u2014 category, mode,
sampleRate, ioBufferDuration, current route (inputs +
outputs), outputVolume. Lets us see whether iOS honoured our
.default + .defaultToSpeaker setup and which physical route
it picked at launch.
2. ios_voice_unit.rs::IosVoiceUnit::start: after unit.start()
succeeds, log the actual OUTPUT and INPUT stream formats
VPIO accepted (sample_rate, channels, sample_format, flags).
If these differ from our requested 48 kHz Int16 mono, we
have a format-substitution problem.
Three possible outcomes from the next test:
* Both diagnostics confirm 48 kHz Int16 mono on both buses and
the session sampleRate=48000 -> format is correct; the
playback breakage is somewhere else (e.g. AudioHandler
jitter buffer behaviour, route binding, or hardware mixer).
* Session sampleRate != 48000 -> we need to insert a sample
rate converter or pin AVAudioSession's
setPreferredSampleRate(48000) explicitly in Swift before
setActive.
* VPIO substituted Float32 for our Int16 request -> our render
callback is writing i16 magnitudes into a Float32 buffer
which would explain the distortion. Fix: write Float32
directly using data::Interleaved<f32> instead of i16.
Build counter 70 -> 71. Pure diagnostic; no behavioural
change.
Edison Jwa