Files
punktfunk/crates/punktfunk-host
enricobuehler 0868b6a364 fix(vdisplay): compositor availability follows the live session, not the env
GNOME/Mutter reported "Unavailable" on a host sitting in a live Mutter
session — and, on the same request, "Default", because the two columns had
different sources. available() asked each backend, and those probes read
the process env (XDG_CURRENT_DESKTOP for Mutter, WAYLAND_DISPLAY for
KWin's registry handshake, SWAYSOCK for sway) — env a host started outside
the session (systemd --user, a TTY, ssh) never inherited. It is only
retargeted at the live session on the connect path, so the answer also
flipped depending on whether anyone had connected yet.

Both columns now come from the same /proc scan detect() already used: the
live session's compositor is usable by definition, as is an explicit
operator pin, and the per-backend probe stays as the fallback for backends
that are not the live session (gamescope, which spawns its own). A live
KWin without the zkde_screencast grant now surfaces as available and fails
at create with that probe's precise message, which beats "no usable
compositor" on a box visibly running KDE.

Mutter's env sniff stays deliberately narrow — one var, not three.
XDG_CURRENT_DESKTOP is the one apply_session_env owns end to end (written
per connect, scrubbed when nothing is live); sniffing DESKTOP_SESSION
alongside would resurrect the bug that scrub exists to prevent, where a
stale value after a gnome-shell crash routes the next client into a dead
session.

Non-Linux hosts now report no compositors at all rather than five Linux
backends flagged unavailable with no default — on Windows the pf-vdisplay
driver is the only backend and vdisplay::open ignores the argument, so the
old list read as broken detection instead of "not applicable here". The
console says so explicitly.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
(cherry picked from commit eb7ba3d6177552f5c3ed6a15439404084869c636)
2026-07-28 17:01:59 +02:00
..

punktfunk-host

The streaming host — the program you run on the machine whose desktop or games you want to stream. For each client that connects, it spins up a virtual display sized to that device, captures it on the GPU, encodes with hardware NVENC/VAAPI/AMF/QSV, and sends it out over a low-latency transport — no physical monitor, no letterboxing, no rearranging your real screens.

It speaks two protocols from one process:

  • GameStream — so any Moonlight / Artemis client works day one.
  • punktfunk/1 — punktfunk's own faster protocol (QUIC control plane, GF(2¹⁶) FEC + AES-GCM data plane) that the native clients use.

Runs on Linux (the primary, most battle-tested path) and Windows (x64). The shared protocol, FEC, and crypto live in punktfunk-core; this crate is everything platform-facing around it.

What it does

  • Per-client virtual displays at the exact WxH@Hz. Linux uses per-compositor backends — KWin, gamescope, Mutter, and Sway/wlroots; Windows uses its own all-Rust IddCx virtual display, even on the secure desktop (UAC / lock screen).
  • GPU zero-copy capture → encode. dmabuf → CUDA/Vulkan → NVENC on Linux; on Windows the host pushes frames straight into its own IDD (sealed IDD-push, no screen-scraping) → GPU encode. Encoders auto-select by GPU vendor: NVENC (NVIDIA), VAAPI (Linux AMD/Intel), AMF/QSV (Windows AMD/Intel), or software H.264 as a floor. HDR/10-bit and HEVC 4:4:4 supported.
  • Input injection. Mouse/keyboard (libei / gamescope EIS / wlr / Windows SendInput) and virtual gamepads — Xbox 360/One, DualSense, DualShock 4 — with rumble and HID feedback back-channels.
  • Audio both ways. Opus audio host→client, plus a virtual microphone the client can talk into.
  • Trust & discovery. A persistent host identity, SPAKE2 PIN pairing (default) or TOFU, and mDNS auto-advertisement so clients find the host without typing an IP.
  • Management API + web console. A REST API (mgmt.rs, OpenAPI at api/openapi.json) drives status, paired devices, and on-demand pairing; the browser UI is in web/.

Run it

punktfunk-host serve runs inside your desktop session. Bare serve is the secure native-only default (punktfunk/1 + the management API); add --gamestream on a trusted LAN to also accept stock Moonlight clients.

# Linux, from the repo root (see the repo README "Running on this box" for the headless recipe):
cargo run -rp punktfunk-host -- serve                 # native-only (secure default)
cargo run -rp punktfunk-host -- serve --gamestream    # + Moonlight compatibility

Then pair from the web console (https://<host-ip>:47992) or the client app.

Most people should install a package rather than run from source — see packaging/ (apt · rpm/COPR/bootc · Arch/sysext · Windows installer) and the per-platform guides at docs.punktfunk.unom.io/docs/install.

Subcommands

Command Purpose
serve The host (native punktfunk/1 + mgmt API; --gamestream adds Moonlight).
punktfunk1-host Standalone native-protocol listener for testing/measurement (--source virtual, --max-sessions).
openapi Print the management-API OpenAPI spec (regenerates api/openapi.json).
library Inspect the multi-store game library.
service · driver · web Windows: SCM service, driver install, bundled web console.
*-test / *-selftest / *-probe Diagnostics (input, zero-copy, HDR, compositor, gamepads).

--help lists them all.

Layout

src/
  main.rs            CLI + subcommand dispatch
  config.rs · session_plan.rs · session_tuning.rs · pipeline.rs   session setup + the frame pipeline
  vdisplay/          per-compositor virtual outputs (kwin · gamescope · mutter · wlroots)
  capture/ · capture.rs    screen/dmabuf capture (+ Windows IDD-push)
  encode/ · encode.rs      per-GPU encoders (nvenc · vaapi · ffmpeg_win (AMF/QSV) · sw)
  linux/zerocopy/    dmabuf → CUDA → NVENC bridges (EGL/GL tiled, Vulkan LINEAR)
  inject/ · inject.rs      input backends (libei · wlr · uinput gamepads · UHID DualSense/DS4)
  audio/ · audio.rs        Opus out + virtual mic (PipeWire / WASAPI)
  gamestream/        Moonlight compat: nvhttp · pairing · rtsp · control · stream · gamepad · apps
  native.rs      the native punktfunk/1 host (QUIC control + native-thread UDP data plane)
  mgmt.rs · native_pairing.rs · stats_recorder.rs   management API, pairing, perf capture
  hdr.rs · library.rs      HDR metadata; multi-store game library
  linux/ · windows/  platform-confined backends
  • punktfunk-core — the shared protocol · FEC · crypto core
  • Clients — the apps that connect (Apple · Linux · Windows · Android · probe)
  • Packaging & docs — install & operate
  • punktfunk-planning (internal planning repo) — architecture rationale and deep-dive plans