# 12 — Appendix: Glossary, File Index, References

## Glossary

### Wayland concepts

Same as Greenfield — see `../greenfield-analysis/12-appendix.md` for
the full Wayland glossary. Key terms: `wl_display`, `wl_registry`,
`wl_compositor`, `wl_surface`, `wl_seat`, `wl_keyboard`, `wl_pointer`,
`wl_touch`, `wl_output`, `wl_shm`, `wl_buffer`, `wl_callback`,
`wl_data_device_manager`, `wl_data_device`, `wl_data_source`,
`wl_data_offer`, `wl_drm`, `wl_subcompositor`, `wl_subsurface`,
`wl_region`.

### xdg-shell concepts

Same as Greenfield — `xdg_wm_base`, `xdg_surface`, `xdg_toplevel`,
`xdg_popup`, `xdg_positioner`, `configure`, `ack_configure`.

### MIT-approach-specific terms

| Term | Meaning |
|---|---|
| **Clean-room implementation** | Software written by an engineer who has NOT read the source code of the original (AGPL) implementation. The engineer writes from a behavioral spec produced by a separate person who MAY have read the AGPL source. This protects against derivative-work claims. |
| **Person A (spec author)** | The engineer who writes the behavioral spec. MAY read AGPL source for reference. Does NOT write implementation code. |
| **Person B (implementer)** | The engineer who writes the implementation. MUST NOT read AGPL source. Implements from spec + MIT references only. |
| **SPEC.md** | The behavioral spec artifact (inputs/outputs/edge cases, NO code). Written by Person A. |
| **CLEAN_ROOM_LOG.md** | Legal-defensibility artifact documenting who read AGPL source, who didn't, when, what they referenced. |
| **AFC test** | Abstraction-Filtration-Comparison test, from *Computer Associates v. Altai* (1992). The legal test for derivative-work infringement in software. Even non-literal similarity (SSO: structure, sequence, organization) can be infringing. |
| **AGPL §13** | The network-use clause of AGPL-3.0. Requires offering source to all users interacting with the modified work over a network. The killer clause for proprietary web services. |
| **GPL dynamic-linking exception** | GPL applies to the entire combined work when statically linked. Dynamic linking is more permissive (LGPL allows it from proprietary code). FSF's strict interpretation says loading a GPL .so into a proprietary process contaminates it. |
| **ProxyFD** | JSON descriptor for a file descriptor sent over WebSocket: `{handle, type, host}`. Same as Greenfield — see `../greenfield-analysis/04-transport.md`. |

### Python-specific terms

| Term | Meaning |
|---|---|
| **pywayland** | Python bindings to libwayland-server, via cffi. Apache-2.0 licensed. |
| **pywlroots** | Python bindings to libwlroots. NCSA/UIUC license (BSD-like). NOT RECOMMENDED — operates above wire-dispatch layer, incompatible with Greenfield's architecture. |
| **python-xkbcommon** | The `xkbcommon` PyPI package. Python bindings to libxkbcommon. MIT licensed. |
| **PyGObject** | Python bindings to GLib/GObject. LGPL-2.1+. Provides `gi.repository.Gst` for GStreamer. |
| **cffi** | C Foreign Function Interface for Python. Used to call C functions from Python without writing a C extension. |
| **asyncio** | Python's async I/O framework, built into the standard library. |
| **aiohttp** | Async HTTP + WebSocket server framework for Python. Apache-2.0. |
| **multiprocessing.Process** | Python's process-spawning primitive. Used to fork one child per Odoo session. |
| **multiprocessing.reduction.send_handle** | Function to pass an open file descriptor from one Python process to another (uses SCM_RIGHTS on Linux). |
| **GLib MainLoop** | GLib's event loop, required by GStreamer. Runs in a separate Python thread. |
| **asyncio.run_coroutine_threadsafe** | Function to schedule a coroutine on an asyncio event loop from a different thread. Used to marshal GStreamer results back to asyncio. |
| **bubblewrap (bwrap)** | Unprivileged sandboxing tool. LGPL-2.0+. Used by Flatpak. |
| **seccomp BPF** | Linux kernel feature for filtering syscalls. Compiled to BPF bytecode, loaded via `bwrap --seccomp <memfd>`. |
| **systemd-run --scope** | systemd command to run a process in a transient cgroup. Used for memory/CPU/PID limits. |
| **memfd_create** | Linux syscall to create an anonymous in-memory file. Python 3.8+ has `os.memfd_create()`. Replaces Greenfield's `createMemoryMappedFile` native addon. |

### Browser-specific terms

| Term | Meaning |
|---|---|
| **WebGL2** | Next-gen WebGL API. Uniform buffer objects, transform feedback, simplified shaders. 97%+ browser support. |
| **WebCodecs** | W3C standard for native video decode/encode in the browser. `VideoDecoder`, `VideoEncoder`, `EncodedVideoChunk`, `VideoFrame`. Replaces FFmpeg Wasm. |
| **OffscreenCanvas** | W3C standard for canvas rendering in a Web Worker. Allows WebGL to run off the main thread. |
| **Web Workers** | W3C standard for running JavaScript in background threads. |
| **SharedArrayBuffer + Atomics** | W3C standard for zero-copy shared memory between workers. Needs COOP/COEP headers. |
| **ImageBitmap** | W3C standard for a GPU-backed bitmap. Transferable between workers. Used by the `web-bitmapbuf` fast path. |
| **WebTransport** | W3C standard (in progress) for UDP-over-QUIC transport. Future replacement for WebSocket+KCP. |
| **OpenH264** | BSD-2-Clause H.264 codec. Cisco's binary release. Used as fallback when WebCodecs is unavailable. |

## File-to-feature index

### Custom browser compositor (PROPRIETARY, clean-room TS)

| File | Role |
|---|---|
| `packages/compositor/src/index.ts` | Public API: `createCompositorSession()` |
| `packages/compositor/src/core/Session.ts` | Top-level session |
| `packages/compositor/src/core/Compositor.ts` | `wl_compositor` global |
| `packages/compositor/src/core/Globals.ts` | Wayland globals registry |
| `packages/compositor/src/surface/Surface.ts` | `wl_surface`, double-buffered state |
| `packages/compositor/src/surface/SurfaceRole.ts` | Role abstraction |
| `packages/compositor/src/surface/Subsurface.ts` | `wl_subsurface` |
| `packages/compositor/src/surface/Subcompositor.ts` | `wl_subcompositor` global |
| `packages/compositor/src/surface/Region.ts` | `wl_region` (pixman-WASM) |
| `packages/compositor/src/surface/FrameCallback.ts` | `wl_callback` |
| `packages/compositor/src/render/Renderer.ts` | 4-phase render pipeline (WebGL2 + OffscreenCanvas) |
| `packages/compositor/src/render/Scene.ts` | One per output |
| `packages/compositor/src/render/View.ts` | Positioned surface |
| `packages/compositor/src/render/Output.ts` | `wl_output`, OffscreenCanvas binding |
| `packages/compositor/src/render/RenderState.ts` | Per-view-per-scene texture + transform |
| `packages/compositor/src/render/Texture.ts` | WebGL2 texture wrapper |
| `packages/compositor/src/render/Loop.ts` | requestAnimationFrame integration |
| `packages/compositor/src/render/shaders/YUVA2RGBA.glsl` | BT.601 YUVA → RGBA |
| `packages/compositor/src/render/shaders/RGBandA2RGBA.glsl` | RGB+Alpha → RGBA |
| `packages/compositor/src/render/shaders/SceneShader.glsl` | Final pass: textured quads |
| `packages/compositor/src/buffer/Shm.ts` | `wl_shm`, BMP-header hack |
| `packages/compositor/src/buffer/BufferContents.ts` | Buffer abstraction (mimeType) |
| `packages/compositor/src/buffer/ImageBitmapBuffer.ts` | web-bitmapbuf fast path |
| `packages/compositor/src/buffer/EncodedFrameBuffer.ts` | H.264/PNG from proxy |
| `packages/compositor/src/transport/Channel.ts` | ARQChannel + SimpleChannel |
| `packages/compositor/src/transport/kcp.ts` | Ported fresh from MIT C ref (skywind3000/kcp) |
| `packages/compositor/src/transport/ReconnectingWebSocket.ts` | Vendored from pladaria (MIT) |
| `packages/compositor/src/transport/BufferStream.ts` | Serial → frame promise resolution |
| `packages/compositor/src/transport/StreamingBuffer.ts` | Per-surface encoded-frame buffer |
| `packages/compositor/src/transport/EncodedFrame.ts` | Wire format parser |
| `packages/compositor/src/transport/EncoderFeedback.ts` | 4-byte decode feedback, 1 Hz |
| `packages/compositor/src/transport/RemoteInputOutput.ts` | FD-over-WebSocket for native apps |
| `packages/compositor/src/transport/RemoteAppLauncher.ts` | Channel setup per app |
| `packages/compositor/src/transport/decoders/WebCodecsFrameDecoder.ts` | WebCodecs VideoDecoder (HW-accelerated) |
| `packages/compositor/src/transport/decoders/OpenH264FrameDecoder.ts` | OpenH264 BSD Wasm fallback |
| `packages/compositor/src/input/Seat.ts` | `wl_seat` global |
| `packages/compositor/src/input/Keyboard.ts` | `wl_keyboard` |
| `packages/compositor/src/input/Pointer.ts` | `wl_pointer` |
| `packages/compositor/src/input/Touch.ts` | `wl_touch` (REAL implementation, not stub) |
| `packages/compositor/src/input/Xkb.ts` | @gfld/compositor-wasm wrapper (REUSED MIT) |
| `packages/compositor/src/input/InputQueue.ts` | Event coalescing |
| `packages/compositor/src/input/InputOutput.ts` | FD abstraction |
| `packages/compositor/src/roles/XdgWmBase.ts` | `xdg_wm_base` global |
| `packages/compositor/src/roles/XdgSurface.ts` | `xdg_surface` role |
| `packages/compositor/src/roles/XdgToplevel.ts` | `xdg_toplevel` role |
| `packages/compositor/src/roles/XdgPopup.ts` | `xdg_popup` role |
| `packages/compositor/src/roles/XdgPositioner.ts` | `xdg_positioner` |
| `packages/compositor/src/roles/Shell.ts` | `wl_shell` (legacy, optional) |
| `packages/compositor/src/roles/ShellSurface.ts` | `wl_shell_surface` (legacy, optional) |
| `packages/compositor/src/data/DataDeviceManager.ts` | `wl_data_device_manager` |
| `packages/compositor/src/data/DataSource.ts` | `wl_data_source` |
| `packages/compositor/src/data/DataOffer.ts` | `wl_data_offer` |
| `packages/compositor/src/data/PrimarySelectionDeviceManager.ts` | **NEW: zwp_primary_selection_v1** |
| `packages/compositor/src/desktop/Desktop.ts` | Floating vs AlwaysFullScreen |
| `packages/compositor/src/desktop/FloatingDesktopSurface.ts` | Default floating mode |
| `packages/compositor/src/userapi/UserShellApi.ts` | OWL shell integration seam |
| `packages/compositor/src/browser/input.ts` | DOM keyboard events |
| `packages/compositor/src/browser/pointer.ts` | DOM pointer events |
| `packages/compositor/src/browser/touch.ts` | DOM touch events (NEW) |
| `packages/compositor/src/browser/dnd.ts` | DnD bridge (NEW: native→DOM DnD) |
| `packages/compositor/src/browser/selection.ts` | Clipboard bridge |
| `packages/compositor/src/math/Mat4.ts` | 4×4 matrix |
| `packages/compositor/src/math/Rect.ts` | Rectangle math |

### Custom Python proxy (PROPRIETARY, ~2880 LOC)

| File | Role |
|---|---|
| `compositor_proxy/main.py` | HTTP + WS hub, forks per session |
| `compositor_proxy/session.py` | Top-level proxy session |
| `compositor_proxy/session_controller.py` | aiohttp WS server with 9 endpoints |
| `compositor_proxy/jwt_auth.py` | JWT validation (pyjwt) |
| `compositor_proxy/native_app_context.py` | Per-app state, signaling WS, kill timers, bwrap spawn |
| `compositor_proxy/native_wayland_client_session.py` | Per-client message dispatcher |
| `compositor_proxy/native_wayland_compositor_session.py` | Display creation, initShm, initDrm |
| `compositor_proxy/channel.py` | ARQChannel + SimpleChannel (clean-room) |
| `compositor_proxy/kcp_adapter.py` | kcp PyPI package integration |
| `compositor_proxy/frame_feedback.py` | Receives 4-byte decode feedback |
| `compositor_proxy/proxy_buffer.py` | Proxy-side buffer representation |
| `compositor_proxy/surface_buffer_encoding.py` | Encoding pipeline orchestration |
| `compositor_proxy/xwayland_session.py` | XWayland spawn + bridge |
| `compositor_proxy/wayland_server.py` | pywayland wrapper + cffi shim |
| `compositor_proxy/io/` | WebSocket server glue |
| `compositor_proxy/encoding/gst_encoder.py` | GStreamer H.264/PNG encoder (~700 LOC) |
| `compositor_proxy/encoding/adaptive_bitrate.py` | Adaptive bitrate controller (NEW) |
| `compositor_proxy/encoding/glib_thread.py` | GLib MainLoop in separate thread |
| `compositor_proxy/sandbox.py` | bubblewrap + seccomp + systemd-run wrappers |

### Reused from Greenfield (MIT/Apache)

| Path | Role |
|---|---|
| `greenfield/protocol/wayland.xml` | Upstream Wayland core (MIT) |
| `greenfield/protocol/xdg-shell.xml` | Stable xdg-shell (MIT) |
| `greenfield/protocol/wayland-drm.xml` | Legacy wl_drm (MIT) |
| `greenfield/protocol/web-bitmapbuf-unstable-v1.xml` | Greenfield's custom extension (MIT) |
| `greenfield/libs/common/src/Connection.ts` | Wire format codec (REUSED) |
| `greenfield/libs/compositor-protocol/src/` | Server-side runtime + generated bindings (REUSED) |
| `greenfield/libs/client-protocol/src/` | Client-side runtime + generated bindings (REUSED) |
| `greenfield/libs/compositor-wasm/src/` | pixman + xkbcommon WASM (REUSED) |
| `greenfield/libs/xtsb/` | X11 TypeScript bindings (REUSED, only if XWayland) |
| `greenfield/libs/client-generator/` | Browser client bindings generator (REUSED) |
| `greenfield/libs/compositor-generator/` | Browser server bindings generator (REUSED) |
| `greenfield/packages/compositor-proxy/native/wayland/src/westfield-buffer.c` | Buffer helpers (REUSED, MIT) |
| `greenfield/packages/compositor-proxy/native/wayland/src/westfield-dmabuf.c` | DMA-BUF import (REUSED, MIT) |
| `greenfield/packages/compositor-proxy/native/wayland/src/westfield-egl.c` | EGL zero-copy setup (REUSED, MIT) |
| `greenfield/packages/compositor-proxy/native/wayland/src/westfield-xwayland.c` | XWayland bridge (REUSED as reference, ported to Python) |
| `greenfield/packages/compositor-proxy/native/wayland/src/wlr_drm.c` | `wl_drm` global impl (REUSED, MIT, vendored from wlroots) |
| `greenfield/packages/compositor-proxy/native/wayland/src/wlr_linux_dmabuf_v1.c` | `zwp_linux_dmabuf_v1` global impl (REUSED, MIT, vendored from wlroots) |
| `greenfield/packages/compositor-proxy/native/wayland/src/drm_format_set.c` | DRM format helpers (REUSED, MIT, vendored from wlroots) |
| `greenfield/packages/compositor-proxy/native/wayland/src/wayland-server/changes.diff` | Patches to libwayland-server (REUSED, MIT, optional for fast-sync) |

### Odoo 20 backend addon

| Path | Role |
|---|---|
| `compositor_shell/__manifest__.py` | Addon manifest |
| `compositor_shell/models/compositor_app.py` | App catalog model |
| `compositor_shell/models/compositor_session.py` | Session model (mail.thread) |
| `compositor_shell/models/compositor_audit_log.py` | Append-only audit log |
| `compositor_shell/controllers/main.py` | HTTP controllers (token, apps, launch, audit) |
| `compositor_shell/security/compositor_security.xml` | Groups + rules |
| `compositor_shell/security/ir.model.access.csv` | ACLs |
| `compositor_shell/views/compositor_app_views.xml` | App management views |
| `compositor_shell/views/compositor_session_views.xml` | Session views |
| `compositor_shell/views/ir_actions_client_views.xml` | OWL action registration |
| `compositor_shell/static/src/components/compositor_shell.js` | OWL shell component |
| `compositor_shell/static/src/components/compositor_shell.xml` | OWL template |
| `compositor_shell/static/src/components/compositor_shell.scss` | Styles |
| `compositor_shell/static/src/lib/compositor_lib/` | Custom browser compositor library (clean-room TS) |

## External references

### Wayland protocol

- **Wayland documentation**: https://wayland.freedesktop.org/docs/html/
- **Wayland protocol XML**: https://gitlab.freedesktop.org/wayland/wayland/-/blob/main/protocol/wayland.xml
- **xdg-shell protocol**: https://gitlab.freedesktop.org/wayland/wayland-protocols/-/blob/main/stable/xdg-shell/xdg-shell.xml
- **wayland-drm protocol**: https://gitlab.freedesktop.org/wayland/wayland/-/blob/main/protocol/wayland.xml
- **linux-dmabuf-unstable-v1**: https://gitlab.freedesktop.org/wayland/wayland-protocols/-/blob/main/unstable/linux-dmabuf/linux-dmabuf-unstable-v1.xml

### libwayland + pywayland

- **libwayland source**: https://gitlab.freedesktop.org/wayland/wayland
- **Wayland book**: https://wayland-book.com/
- **pywayland docs**: https://pywayland.readthedocs.io/
- **pywayland source**: https://github.com/flacjacket/pywayland
- **pywayland on PyPI**: https://pypi.org/project/pywayland/

### wlroots + pywlroots

- **wlroots source**: https://gitlab.freedesktop.org/wlroots/wlroots
- **wlroots mirror**: https://github.com/swaywm/wlroots
- **pywlroots source**: https://github.com/flacjacket/pywlroots
- **Smithay (Rust alternative)**: https://github.com/Smithay/smithay

### xkbcommon + python-xkbcommon

- **xkbcommon homepage**: https://xkbcommon.org/
- **xkbcommon source**: https://github.com/xkbcommon/libxkbcommon
- **xkbcommon on PyPI**: https://pypi.org/project/xkbcommon/

### GStreamer + PyGObject

- **GStreamer homepage**: https://gstreamer.freedesktop.org/
- **GStreamer Python bindings (gst-python)**: https://github.com/GStreamer/gst-python
- **PyGObject docs**: https://pygobject.readthedocs.io/
- **GStreamer tutorials**: https://gstreamer.freedesktop.org/documentation/tutorials/index.html
- **GStreamer GL plugins**: https://gstreamer.freedesktop.org/documentation/opengl/index.html
- **vaapih264enc docs**: https://gstreamer.freedesktop.org/documentation/vaapi/index.html
- **nvh264enc docs**: https://gstreamer.freedesktop.org/documentation/nvcodec/index.html
- **openh264enc docs**: https://gstreamer.freedesktop.org/documentation/openh264/index.html

### OpenH264 (BSD fallback decoder)

- **OpenH264 source**: https://github.com/cisco/openh264
- **Cisco binary releases**: https://github.com/cisco/openh264/releases

### WebCodecs + WebGL2 + OffscreenCanvas

- **WebCodecs API (MDN)**: https://developer.mozilla.org/en-US/docs/Web/API/WebCodecs_API
- **VideoDecoder (MDN)**: https://developer.mozilla.org/en-US/docs/Web/API/VideoDecoder
- **WebGL2 (MDN)**: https://developer.mozilla.org/en-US/docs/Web/API/WebGL2RenderingContext
- **OffscreenCanvas (MDN)**: https://developer.mozilla.org/en-US/docs/Web/API/OffscreenCanvas
- **Web Workers (MDN)**: https://developer.mozilla.org/en-US/docs/Web/API/Web_Workers_API
- **SharedArrayBuffer (MDN)**: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/SharedArrayBuffer
- **WebTransport (MDN)**: https://developer.mozilla.org/en-US/docs/Web/API/WebTransport
- **WebCodecs samples**: https://w3c.github.io/webcodecs/samples/

### KCP

- **KCP protocol (skywind3000)**: https://github.com/skywind3000/kcp
- **KCP documentation**: https://skywind3000.github.io/kcp/
- **kcp on PyPI (RealistikDash)**: https://pypi.org/project/kcp/

### asyncio + aiohttp

- **asyncio docs**: https://docs.python.org/3/library/asyncio.html
- **aiohttp docs**: https://docs.aiohttp.org/
- **aiohttp WebSocket**: https://docs.aiohttp.org/en/stable/web_advanced.html#websockets

### JWT

- **PyJWT docs**: https://pyjwt.readthedocs.io/
- **JWT.io**: https://jwt.io/
- **RFC 7519 (JWT)**: https://datatracker.ietf.org/doc/html/rfc7519

### Sandboxing

- **bubblewrap docs**: https://github.com/containers/bubblewrap
- **libseccomp**: https://github.com/seccomp/libseccomp
- **Flatpak sandboxing**: https://docs.flatpak.org/en/latest/sandbox-permissions.html
- **cgroups v2**: https://www.kernel.org/doc/html/latest/admin-guide/cgroup-v2.html
- **systemd-run**: https://www.freedesktop.org/software/systemd/man/systemd-run.html

### Odoo 20

- **Odoo 20 documentation**: https://www.odoo.com/documentation/20.0/
- **Odoo OWL framework**: https://github.com/odoo/owl
- **Odoo OWL migration guide (Odoo 19→20)**: https://www.odoo.com/documentation/20.0/developer/howtos/owl_migration.html
- **Odoo controller patterns**: https://www.odoo.com/documentation/20.0/developer/howtos/routing.html
- **Odoo security**: https://www.odoo.com/documentation/20.0/developer/howtos/security.html

### Greenfield (for reference, NOT for clean-room implementers)

- **Greenfield homepage**: https://www.greenfield.app
- **Greenfield source**: https://github.com/udevbe/greenfield
- **Greenfield design docs**: https://github.com/udevbe/greenfield/blob/master/docs/pages/design/index.md
- **Greenfield MIT libs (REUSABLE)**: https://github.com/udevbe/greenfield/tree/master/libs
- **Greenfield AGPL packages (DO NOT READ for clean-room)**: https://github.com/udevbe/greenfield/tree/master/packages

### Westfield (Greenfield's predecessor, MIT)

- **Westfield source**: https://github.com/udevbe/westfield
- **Note**: Contains ONLY the protocol infrastructure (same as Greenfield's MIT libs). NEVER had the in-browser compositor logic.

### Reference Wayland compositors (MIT, for clean-room spec authors)

- **wlroots (C, MIT)**: https://gitlab.freedesktop.org/wlroots/wlroots — reference for compositor patterns
- **Weston (C, MIT)**: https://gitlab.freedesktop.org/wayland/weston — reference Wayland compositor
- **Smithay (Rust, MIT)**: https://github.com/Smithay/smithay — Rust compositor library
- **wprs (Rust, MIT)**: https://github.com/Smithay/wprs — Rust wayland-xpra, mirrors Greenfield's architecture almost exactly

## Pointers to the user's next steps

1. **Read the comparison document**: `../Greenfield-vs-MIT-Comparison.md`
   for the head-to-head analysis and final recommendation.

2. **If you choose the MIT approach** (recommended):
   - Phase 0: Spike (1 week) — validate libwayland ↔ asyncio integration
   - Phase 1: Browser compositor MVP (25 weeks, clean-room TS)
   - Phase 2: Python proxy MVP (3.5 weeks, aiohttp + pywayland + GStreamer)
   - Phase 3: Odoo integration (3.5 weeks, OWL shell + backend addon + JWT)
   - Phase 4: Sandboxing v1 (1.5 weeks, bubblewrap + seccomp)
   - Phase 5: Polish & testing (3 weeks)

3. **Critical first step**: Set up the clean-room process.
   - Designate Person A (spec author) and Person B (implementer)
   - Person A reads Greenfield AGPL source + writes `SPEC.md`
   - Person B implements from `SPEC.md` + MIT references only
   - Maintain `CLEAN_ROOM_LOG.md` as a legal-defensibility artifact

4. **CI/CD license hygiene gates**: Add the 4 license checks to your CI
   pipeline from day one. See `11-pitfalls.md` for the commands.

5. **Engage legal counsel** before starting the clean-room process. This
   bundle is engineering analysis, not legal advice.