Step 2b.1: structural split (no function decomposition — that's 2b.2).
src/cap_portal.rs (1313 -> 176 LOC) now contains only the CapPortal struct,
its constructor (new), accessors (frame_receiver/event_receiver/dropped_count/
capture_queue_depth), and Drop impl. Six new sibling submodules under
src/cap_portal/:
- types.rs (79 LOC) timeout constants, PortalPhaseTimeout enum,
pub types PwDmaBufFrame / PortalFormatInfo /
PwCtrlEvent
- logging.rs (18 LOC) log_portal_phase_timeout helper
- fourcc.rs (73 LOC) spa_to_drm_fourcc + its 2 tests
- token_fs.rs (362 LOC) 8 restore-token fs helpers + 11 security tests
- setup.rs (192 LOC) impl CapPortal { setup_portal + _setup_portal_inner }
(associated fns; no self access — clean extract)
- pipewire_thread.rs (446 LOC) PwThreadCtx (now private to this file),
pipewire_thread body (verbatim, 18 SAFETY
comments preserved), new spawn_pipewire_thread
helper that constructs PwThreadCtx internally
and returns JoinHandle. CapPortal::new now calls
pipewire_thread::spawn_pipewire_thread(...) instead
of inlining the PwThreadCtx construction.
Oracle audit points honored:
- PwThreadCtx moved as a whole; Drop in mod.rs and pipewire_thread in
pipewire_thread.rs share zero state through it (PwThreadCtx consumed
by-value inside pipewire_thread; spawn helper owns the construction).
- All // SAFETY comments travel verbatim with their unsafe blocks.
- The 18 SAFETY comments in pipewire_thread are intact; clippy
undocumented_unsafe_blocks=deny still passes.
API stability:
- pub use types::{PwCtrlEvent, PwDmaBufFrame} preserves the existing
wl_webrtc::cap_portal::{PwCtrlEvent, PwDmaBufFrame} paths used by
both bench binaries (verified by cargo check --bin vaapi_import_bench
--bin sw_encode_bench).
- PortalFormatInfo was nominally pub in the original file but never
referenced outside cap_portal; kept pub in types.rs (for cross-
submodule access) but not re-exported from cap_portal.rs, so the
accidental over-exposure is now scoped back.
Verification (all green):
- cargo build / cargo build --release
- cargo test (79 lib + 3 integration = 82 pass, 1 ignored — unchanged)
- cap_portal test count: 13 (fourcc=2 + token_fs=11) — matches baseline
- cargo clippy --all-targets -- -D warnings
- cargo fmt --check
- cargo check --bin vaapi_import_bench --bin sw_encode_bench
