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refactor: drop milestone names + consolidate clients; loss-recovery & rumble fixes
Two bodies of work in one commit (the rename moved files the fixes also touched).

Naming/structure cleanup (pre-launch):
- Host modules m3.rs->punktfunk1.rs, m0.rs->spike.rs; CLI m3-host->punktfunk1-host,
  m0->spike; bare `punktfunk-host` now prints help. Types M3Options/M3Source->
  Punktfunk1Options/Punktfunk1Source.
- Clients consolidated out of crates/ into clients/: punktfunk-client-rs->
  clients/probe (crate punktfunk-probe), client-linux->clients/linux,
  client-windows->clients/windows, punktfunk-android->clients/android/native
  (crate punktfunk-client-android; kept [lib] name=punktfunk_android so the JNI
  contract is unchanged). crates/ now holds only core + host.
- Milestone codes M0-M4 purged from code/CLI/CLAUDE.md/README/docs/docs-site,
  kept only in docs/implementation-plan.md. docs/m2-plan.md->
  docs/gamestream-host-plan.md. CI/gradle/flatpak paths updated.

Client loss-recovery (video froze and never recovered after a brief drop):
- Export punktfunk_connection_frames_dropped through the C ABI (the core already
  tracked it for the client keyframe-recovery loop; it was never reachable from
  the ABI clients). Regenerated punktfunk_core.h.
- Apple (StreamPump + Stage2Pipeline) and Android (decode.rs) now poll
  frames_dropped and request a keyframe when it climbs -- the same loss-driven
  recovery Linux/Windows already had. Under infinite GOP the decoder silently
  conceals reference-missing frames, so the decode-error trigger rarely fires.

Apple rumble robustness (worked then went spotty -- DualSense + Xbox):
- Add CHHapticEngine stopped/reset handlers (rebuild on app background / audio
  interruption / server reset) and drop the permanent `broken` latch on a
  transient drive failure; latch only when the controller truly has no haptics.
- Surface swallowed SDL set_rumble errors on Linux/Windows + diagnostic logging.

Verified: cargo build/clippy/fmt --workspace, C-ABI harness, header drift.
Not runnable on this box (verify in CI): Gitea workflows, gradle/Android,
flatpak, Swift/decky.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
2026-06-18 21:05:58 +00:00

4.9 KiB

title, description
title description
gamescope Multi-User Isolation (deferred) Research + design for concurrent INDEPENDENT gamescope desktops (multi-user), and why it's deferred. The shared-desktop multi-view case already landed.

Status: deferred (2026-06-12). Concurrent sessions landed for the shared-desktop multi-view case — multiple devices viewing/controlling the same KWin/Mutter/wlroots desktop (Status). This page captures the research for the other model — independent desktops (each client its own gamescope instance: the multi-user / cloud-gaming-on-one-box case) — and why it's parked. Pick this up from here if the use case becomes a priority.

What landed vs what this is

Model Backends Input Audio Status
Shared-desktop multi-view kwin / mutter / wlroots shared (all drive one desktop) shared (all hear one desktop) landed — correct semantics: stream your desktop to laptop + TV at once
Independent desktops (multi-user) gamescope per-session (each drives its own game) per-session deferred — this page

For independent desktops, shared input/audio is wrong — each user must drive and hear only their own session. gamescope is the natural fit: each create() spawns a fresh nested compositor (own rendering, own EIS input socket). The blocker is that the host's input/audio/mic are host-lifetime shared services, and the gamescope EIS socket is relayed through a single global file.

Current architecture (the research)

Each gamescope process is per-session (vdisplay/gamescope.rs::create() spawns one; the VirtualOutput.keepalive owns it). But:

  • EIS input socket — single global file. gamescope exports LIBEI_SOCKET for its children; a shell wrapper relays it to the fixed path /tmp/punktfunk-gamescope-ei (EI_SOCKET_FILE). Two concurrent instances overwrite each other's socket name in that one file.
  • Injector — one host-lifetime !Send service. punktfunk1.rs::InjectorService opens one inject::open(backend) for the whole run and forwards events over an mpsc channel. It was made shared deliberately (the portal CreateSession churn wedged KWin's EIS — "EIS setup timed out"). For gamescope it reads the one global socket file, so all sessions' input lands in whichever instance wrote last.
  • Audio — global default-sink monitor. audio::open_audio_capture() sets STREAM_CAPTURE_SINK and autoconnects to the host's default sink monitor (PW_ID_ANY) — the whole system's output, not a per-gamescope node. gamescope exposes no per-instance audio node.
  • Mic — one global Audio/Source. MicService feeds one PipeWire source named punktfunk-mic; all clients' mic uplinks mix into it.
  • Per-session already (no work): the gamescope process, the PipeWire video node, and the uinput gamepads.

What it would take

  1. Per-instance EIS socket — give each gamescope a unique relay file (/tmp/punktfunk-gamescope-{id}-ei) and carry the path on VirtualOutput (new field) so the session can find its own socket.
  2. Per-session injector — for gamescope sessions, create a per-session injector bound to that socket (its own thread, since InputInjector is !Send), instead of the shared InjectorService. Keep the shared service for the portal backends (kwin/mutter) where shared input is correct. Ordering nuance: the input thread is wired before the gamescope socket exists, so the per-session injector must open lazily (on first event, by which time gamescope is up) or be created after build_pipeline.
  3. Per-session audio (the bigger piece). gamescope has no per-instance audio node, but audio is isolatable: create a per-session PipeWire null-sink, route that gamescope's apps to it (PULSE_SINK / a target node on the spawn env), and capture that sink's monitor per session. This is the largest addition — null-sink create/teardown + routing + per-session capture.
  4. Per-session mic — a virtual Audio/Source per session (punktfunk-mic-{id}), routed into that gamescope, instead of the one global source.

Why deferred

  • It's a large multi-file refactor — the whole input path (per-instance sockets + per-session injector + the lazy-open ordering), plus per-session null-sink audio routing, plus per-session mic — for a niche use case (multiple independent users gaming on one box).
  • The common concurrency case — stream one desktop to several of your own devices — is the shared-desktop multi-view model, which already landed and is the correct semantics for it.
  • No correctness gap in what shipped: concurrent sessions work today; this is purely the additional independent-desktops model.

Revisit when there's a real multi-user requirement. The plumbing list above is the whole job.