//! `HostConfig` — the host's runtime knobs parsed ONCE from the environment, instead of the ~68 scattered //! `env::var` reads recomputed at every call site (some up to 8×, which lets capture + encode silently //! disagree on the resolved backend — plan §2.4). The service / launcher loads `host.env` into the process //! environment before the host starts, and **for the knobs captured here the environment is constant for the //! process lifetime**, so a lazily-parsed global is equivalent to "parsed once at startup". //! //! **Goal-1 stages 1–2** (`design/windows-host-rewrite.md` §2.2): stage 1 stood this up; stage 2 migrated the //! genuinely-constant operator/dispatch knobs onto it (the dispatch-disagreement bug class: `idd_push`, //! `capture_backend`, `encoder_pref`, `render_adapter`, `no_wgc`, the vdisplay backend select — plus the //! plan-named `secure_dda`/`idd_depth`/`zerocopy`/`ten_bit` and the multi-site `perf`/`compositor`/ //! `video_source`/`gamepad`). `SessionPlan` (stage 3) consumes it as the single owner of the //! capture/topology/encoder decision. //! //! **What is deliberately NOT here (and must stay a live `env::var` read):** //! - **Runtime-mutated session vars.** On Linux, [`crate::vdisplay::apply_session_env`] rewrites the process //! env on *every connect* so one host follows a Bazzite box across Gaming↔Desktop: `WAYLAND_DISPLAY`, //! `XDG_CURRENT_DESKTOP`, `XDG_RUNTIME_DIR`, `DBUS_SESSION_BUS_ADDRESS`, and the *derived* `PUNKTFUNK_*` //! vars `INPUT_BACKEND`, `GAMESCOPE_SESSION`/`GAMESCOPE_NODE`, `KWIN_VIRTUAL_PRIMARY`, //! `MUTTER_VIRTUAL_PRIMARY`, `FORCE_SHM` (+ `GAMESCOPE_APP` on the launch path). Parsing these once would //! freeze them at startup and silently break session-following — they are NOT constant. //! - **Single-use local tuning** read exactly where it is used (no resolve-once benefit, and a parse with a //! call-site-local default/clamp): e.g. `FEC_PCT` (two *different* semantics — GameStream default-20 vs //! punktfunk/1 `Option`/clamp-90), `VIDEO_DROP`, `VBV_FRAMES`, `SPLIT_ENCODE`, `PACE_BURST_KB`, the //! `capture/dxgi.rs` timing knobs, the `*_LIVE` test gates. //! - **Path / genuinely-dynamic reads**: the config-dir resolution, `PATH` executable search, the //! env-forward-to-child loop, `PUNKTFUNK_MGMT_TOKEN`, `PUNKTFUNK_HOST_CMD`, `PUNKTFUNK_RENDER_NODE`. //! //! `PUNKTFUNK_ZEROCOPY` note: this field uses **presence** semantics (`var_os(..).is_some()`) to match the //! Windows `encode/ffmpeg_win.rs` reader. The Linux `zerocopy` module keeps its own *truthy* parser //! (`1|true|yes|on`) — the two are independent features that share a name; do NOT conflate them. use std::sync::OnceLock; /// Resolved host configuration. Holds the genuinely-constant operator/dispatch knobs (see module docs for /// what is deliberately excluded). Fields read on only one platform are kept alive cross-platform by the /// derived `Debug` impl, so the parser can stay a single platform-neutral function. #[derive(Debug, Clone, Default)] pub struct HostConfig { /// `PUNKTFUNK_IDD_PUSH` — capture from the pf-vdisplay driver's shared ring (in-process Session-0 /// capture; no WGC helper). **Value-aware** (`0`/`false`/`no`/`off`/empty ⇒ off, else on); unset ⇒ off. /// The installer's default `host.env` sets it on, so a fresh install runs the validated IDD-push path /// (it falls back to DDA if the driver can't attach — see [`crate::capture`]). NOT a bare presence flag /// (so an operator can turn it OFF in `host.env` with `=0`, which a `var_os` presence check can't). pub idd_push: bool, /// `PUNKTFUNK_ENCODER` — explicit encoder-backend override (lowercased; empty = auto-detect by GPU vendor). pub encoder_pref: String, /// `PUNKTFUNK_NO_HELPER` — never spawn the user-session WGC helper. pub no_helper: bool, /// `PUNKTFUNK_FORCE_HELPER` — force the WGC helper even when not running as SYSTEM. pub force_helper: bool, /// `PUNKTFUNK_NO_WGC` — force the pure single-process DDA path (skip WGC and the two-process relay). pub no_wgc: bool, /// `PUNKTFUNK_CAPTURE` — explicit Windows capture-backend override (lowercased; `dda`/`dxgi` vs the WGC default). pub capture_backend: String, /// `PUNKTFUNK_RENDER_ADAPTER` — discrete render-GPU pin by description substring (`Some` even when empty: /// the empty string still counts as "set" for the presence checks, and the value reader filters it). pub render_adapter: Option, /// `PUNKTFUNK_SECURE_DDA` — enable the experimental DDA-on-secure-desktop (Winlogon/UAC) mux leg. pub secure_dda: bool, /// `PUNKTFUNK_IDD_DEPTH` — IDD-push pipeline depth override (default 2; the call site clamps to its `OUT_RING`). pub idd_depth: usize, /// `PUNKTFUNK_ZEROCOPY` — opt into the Windows D3D11 zero-copy encode path (presence semantics; see module docs). pub zerocopy: bool, /// `PUNKTFUNK_10BIT` — host policy gate for HEVC Main10 (only honored when the client also advertised 10-bit). pub ten_bit: bool, /// `PUNKTFUNK_PERF` — per-stage timing instrumentation. pub perf: bool, /// `PUNKTFUNK_VIDEO_SOURCE` — GameStream video source select (`virtual` / `portal` / unset → synthetic). pub video_source: Option, /// `PUNKTFUNK_COMPOSITOR` — explicit compositor override (operator/CI/test). NOT the runtime-detected /// session — this one is a constant operator knob; `apply_session_env` never writes it. pub compositor: Option, /// `PUNKTFUNK_GAMEPAD` — client/operator virtual-pad backend preference (fed to `pick_gamepad`). pub gamepad: Option, /// `PUNKTFUNK_VDISPLAY` — Windows virtual-display backend. The pf-vdisplay IddCx driver is now the only /// backend (the legacy SudoVDA backend was removed), so this is currently informational — kept for the /// shipped `host.env` and as a forward seam if a second backend is ever added. pub vdisplay: Option, } impl HostConfig { fn from_env() -> Self { // Presence flag: set ⇒ true. Matches the original `var_os(k).is_some()` reads (and the few // `var(k).is_ok()` flag reads, which coincide for every real-world value). let flag = |k: &str| std::env::var_os(k).is_some(); // String value: `var(k).ok()` — `Some` (possibly empty) when set with valid UTF-8, else `None`. let val = |k: &str| std::env::var(k).ok(); Self { // Value-aware (not a bare presence flag): the shipped default `host.env` turns it ON, and an // operator turns it OFF with `PUNKTFUNK_IDD_PUSH=0` (a `var_os` presence check would read `=0` // as "on"). Unset ⇒ off (the dev / non-pf-driver default). idd_push: match std::env::var("PUNKTFUNK_IDD_PUSH") { Ok(v) => !matches!( v.trim().to_ascii_lowercase().as_str(), "" | "0" | "false" | "no" | "off" ), Err(_) => false, }, encoder_pref: std::env::var("PUNKTFUNK_ENCODER") .unwrap_or_default() .to_ascii_lowercase(), no_helper: flag("PUNKTFUNK_NO_HELPER"), force_helper: flag("PUNKTFUNK_FORCE_HELPER"), no_wgc: flag("PUNKTFUNK_NO_WGC"), capture_backend: std::env::var("PUNKTFUNK_CAPTURE") .unwrap_or_default() .to_ascii_lowercase(), render_adapter: val("PUNKTFUNK_RENDER_ADAPTER"), secure_dda: flag("PUNKTFUNK_SECURE_DDA"), idd_depth: val("PUNKTFUNK_IDD_DEPTH") .and_then(|s| s.parse::().ok()) .unwrap_or(2), zerocopy: flag("PUNKTFUNK_ZEROCOPY"), ten_bit: flag("PUNKTFUNK_10BIT"), perf: flag("PUNKTFUNK_PERF"), video_source: val("PUNKTFUNK_VIDEO_SOURCE"), compositor: val("PUNKTFUNK_COMPOSITOR"), gamepad: val("PUNKTFUNK_GAMEPAD"), vdisplay: val("PUNKTFUNK_VDISPLAY"), } } } /// The process-wide host configuration, parsed once on first access. pub fn config() -> &'static HostConfig { static CFG: OnceLock = OnceLock::new(); CFG.get_or_init(HostConfig::from_env) }