chore(engine): the audio rung's removals — the FIXME closes and the dead sync machinery goes

docker/pipewire/10-virtual.conf

@@ -1,9 +1,10 @@
 # Declarative virtual audio devices for the headless StreamLib container.
 #
-# StreamLib's Linux audio is cpal -> ALSA (packages/audio), and the container
-# bridges ALSA -> PipeWire via `pipewire-alsa`. This drop-in declares a virtual
-# null sink (plus its recordable `.monitor` source) at PipeWire startup so the
-# devices exist with no hardware, no `/dev/snd`, and no imperative `pactl` race.
+# StreamLib reaches this daemon directly: its backend chain dlopen's
+# libpipewire, falling back to libasound and then to the null backend. This
+# drop-in declares a virtual null sink (plus its recordable `.monitor` source)
+# at PipeWire startup so the devices exist with no hardware, no `/dev/snd`, and
+# no imperative `pactl` race.
 #
 # Loaded from /etc/pipewire/pipewire.conf.d/ — keys are UNQUOTED, string values
 # ARE quoted; a syntax error silently drops the section.

runtime/streamlib-engine/src/core/context/audio_clock.rs

@@ -50,7 +50,11 @@ impl AudioClockConfig {
 /// Context passed to audio clock tick callbacks.
 #[derive(Debug, Clone, Copy)]
 pub struct AudioTickContext {
-    /// Machine monotonic timestamp in nanoseconds, the epoch a frame timestamp carries.
+    /// Machine monotonic timestamp in nanoseconds, the epoch a frame timestamp
+    /// carries. It is the wake time rather than the expiration the tick was
+    /// scheduled for, and a catch-up burst may hand every tick the same one, so
+    /// a block's instant derives from an anchor plus samples already delivered
+    /// — never from one tick's stamp.
     pub timestamp_ns: i64,
     /// Number of samples to produce this tick (per channel).
     pub samples_needed: usize,

runtime/streamlib-engine/src/core/mod.rs

@@ -40,7 +40,6 @@ pub mod processors;
 pub mod pubsub;
 pub mod rhi;
 pub mod runtime;
-pub mod sync;
 pub mod texture;
 pub mod utils;
 // Linux-only: winit is a Linux-target engine dependency, and the window seam
@@ -60,7 +59,6 @@ pub use graph_snapshot::*;
 pub use processors::*;
 pub use rhi::{GlContext, GlTextureBinding, NativeTextureHandle, RhiBackend, gl_constants};
 pub use runtime::*;
-pub use sync::*;
 pub use texture::*;
 pub use utils::*;
 

runtime/streamlib-engine/src/core/observability/perception.rs

@@ -37,19 +37,6 @@ pub struct SampledFrame {
     pub timestamp_ns: i64,
 }
 
-/// A sampled audio buffer for AI perception.
-#[derive(Debug, Clone)]
-pub struct SampledAudio {
-    /// Audio samples (f32 interleaved).
-    pub samples: Vec<f32>,
-    /// Sample rate in Hz.
-    pub sample_rate: u32,
-    /// Number of channels.
-    pub channels: u32,
-    /// Duration in milliseconds.
-    pub duration_ms: u32,
-}
-
 /// Current status of a processor.
 #[derive(Debug, Clone)]
 pub struct ProcessorStatus {
@@ -68,9 +55,6 @@ pub trait AgentPerception: Send + Sync {
     /// Sample a video frame from a processor's output.
     fn sample_video(&self, id: &ProcessorId, config: SampleConfig) -> Option<SampledFrame>;
 
-    /// Sample audio from a processor's output.
-    fn sample_audio(&self, id: &ProcessorId, duration_ms: u32) -> Option<SampledAudio>;
-
     /// Get current status of a processor.
     fn processor_status(&self, id: &ProcessorId) -> Option<ProcessorStatus>;
 

runtime/streamlib-engine/src/iceoryx2/delivery_profile.rs

@@ -37,12 +37,12 @@ pub enum DeliveryProfile {
     /// stale sample has no value once a fresher one exists.
     Latest,
     /// FIFO with a bounded backlog: read next in order, evict + count the
-    /// oldest under sustained overrun, deeper ring. Sample streams — audio,
-    /// encoded frames — where order matters but the producer must never block.
+    /// oldest under sustained overrun, deeper ring. Sample streams — encoded
+    /// frames — where order matters but the producer must never block.
     EverySample,
     /// Lossless FIFO: read next in order, the producer blocks rather than
-    /// drop, deeper ring. File writers, muxers, loggers where every sample
-    /// must be delivered.
+    /// drop, deeper ring. Audio, file writers, muxers, loggers where every
+    /// sample must be delivered.
     ///
     /// What this configures is the *publisher's* policy, and that is as far as
     /// it reaches today: the consumer's host mailbox

runtime/streamlib-engine/src/iceoryx2/node.rs

@@ -104,11 +104,10 @@ impl Iceoryx2Node {
     /// [`crate::iceoryx2::delivery_profile_for_input_port`].
     ///
     /// `enable_safe_overflow` derives from that same profile's overflow policy.
-    /// When `true` (the realtime default — `Overflow::DropOldest`), the subscriber
-    /// buffer auto-evicts the oldest sample on overflow and the publisher's
-    /// `send()` never blocks. When `false` (`Overflow::Block`, the `lossless`
-    /// profile), the producer blocks until the consumer drains a slot — reserve
-    /// for muxers / file writers that need every sample in order.
+    /// When `true` (`Overflow::DropOldest`), the subscriber buffer auto-evicts
+    /// the oldest sample on overflow and the publisher's `send()` never blocks.
+    /// When `false` (`Overflow::Block`, the `lossless` profile), the producer
+    /// blocks until the consumer drains a slot.
     pub fn open_or_create_service(
         &self,
         service_name: &str,

runtime/streamlib-engine/src/iceoryx2/overflow.rs

@@ -20,16 +20,14 @@ use serde::{Deserialize, Serialize};
 #[derive(Debug, Clone, Copy, PartialEq, Eq, Default, Serialize, Deserialize)]
 #[serde(rename_all = "snake_case")]
 pub enum Overflow {
-    /// Buffer evicts oldest sample to make room; publisher never blocks.
-    /// The realtime-media default — producer represents real-world
-    /// time advancing and must not be made to wait. Glitches on the
-    /// consumer side beat freezing the whole pipeline.
+    /// Buffer evicts oldest sample to make room; publisher never blocks — a
+    /// producer that represents real-world time advancing must not be made to
+    /// wait, and glitches on the consumer side beat freezing the whole pipeline.
     #[default]
     DropOldest,
-    /// Producer blocks until the consumer drains a slot. Use only when
-    /// every sample must be delivered in order — file writers, muxers,
-    /// loggers — and the consumer's mailbox `buffer_size` is sized for
-    /// the expected hiccup envelope.
+    /// Producer blocks until the consumer drains a slot. Use only where every
+    /// sample must be delivered in order and the consumer's mailbox
+    /// `buffer_size` is sized for the expected hiccup envelope.
     Block,
 }
 

runtime/streamlib-engine/src/lib.rs

@@ -102,7 +102,6 @@ pub use core::{
     ConnectionDefinition,
     // Processor traits (mode-specific)
     ContinuousProcessor,
-    DEFAULT_SYNC_TOLERANCE_MS,
     Error,
     GlContext,
     GlTextureBinding,
@@ -128,13 +127,11 @@ pub use core::{
     TexturePoolDescriptor,
     TextureUsages,
     TimeContext,
-    are_synchronized,
     gl_constants,
     // Port marker traits and helpers for compile-time safe connections
     input,
     media_clock::MediaClock,
     output,
-    timestamp_delta_ms,
 };
 
 // GPU Backends - Metal and Vulkan
@@ -288,7 +285,6 @@ pub mod sdk {
     pub use crate::core::prelude;
     pub use crate::core::rhi;
     pub use crate::core::runtime;
-    pub use crate::core::sync;
     pub use crate::core::texture;
     pub use crate::core::utils;
 

runtime/streamlib-engine/src/linux/audio_clock.rs

@@ -272,14 +272,6 @@ fn run_timerfd_loop(
             return Err(Error::Runtime(format!("timerfd read failed: {}", err)));
         }
 
-        // FIXME(audio-backend): one read stamps every tick in a catch-up burst, so
-        // N blocks of samples claim the same instant, and the value is the wake
-        // time rather than the expiration the timerfd was programmed for. Both
-        // follow from the timer's own absolute schedule. Deferred because a
-        // free-running clock's tick time is meaningless until a device paces it:
-        // the audio backend is OPEN (docs/plan/ARCHITECTURE.md §Media I/O), and it
-        // also owns the capture path's discarded driver stamp
-        // (cpal `InputCallbackInfo::timestamp().capture`).
         let timestamp_ns = MediaClock::now().as_nanos() as i64;
 
         if expirations > 1 {

sdk/streamlib-sdk/src/lib.rs

@@ -94,7 +94,6 @@ pub mod sdk {
 
     #[cfg(target_os = "linux")]
     pub use streamlib_engine::core::processor_owned_window;
-    pub use streamlib_engine::core::sync;
     pub use streamlib_engine::core::texture;
     #[cfg(target_os = "linux")]
     pub use streamlib_engine::core::window_event_pump;