# Embedded MPV Runtime This directory owns the source builders, staging, manifests, and archive helpers for IPTVnator's experimental Embedded MPV runtime. The Linux architecture has a strict process boundary: - Electron, `embedded_mpv.node`, and `embedded_mpv_frame_reader.node` must not load or link libmpv. - Native-view starts a separate system `mpv --wid` process. - Frame-copy starts `iptvnator_mpv_helper`; only that helper may link libmpv. Do not weaken this boundary to simplify packaging. A missing helper/runtime must make frame-copy unavailable and leave native-view as the safe x64 fallback. ## Runtime Policy Release builds use an LGPL-compatible, dynamically linked runtime: - FFmpeg is built without `--enable-gpl` and `--enable-nonfree`. - mpv is built with `-Dlibmpv=true` and `-Dgpl=false`. - Bundled libraries remain individually replaceable under `native/lib`. - Exact source URLs, versions, checksums or git commits, submodules, licenses, build flags, local patches, and build scripts are published with the release. Homebrew mpv is local-development-only. It requires `IPTVNATOR_EMBEDDED_MPV_ALLOW_HOMEBREW=1`, and release validation rejects it. ## Generated Layout ```text vendor/embedded-mpv/ darwin-arm64/ include/mpv/client.h lib/*.dylib runtime-manifest.json darwin-x64/ include/mpv/client.h lib/*.dylib runtime-manifest.json win32-x64/ include/mpv/client.h lib/libmpv-2.dll # accepted basename variants are preserved lib/libmpv.dll.a # or an MSVC import library runtime-manifest.json linux-x64/ include/mpv/client.h lib/libmpv.so lib/libmpv.so.2 lib/ notices/embedded-mpv-notices.json notices/THIRD_PARTY_NOTICES.txt notices/licenses// runtime-manifest.json ``` These directories are generated release inputs and are ignored by git. `runtime-manifest.json` is the profile-neutral source/build manifest. Packaging writes a normalized `embedded-mpv-runtime.json` beside the native artifacts. Bundled Linux profiles flatten the three notice entries from `notices/` into that same native directory; system and marker-only profiles remove them. ## Building And Staging Stage an existing compatible prefix with: ```bash pnpm embedded-mpv:stage-runtime -- darwin arm64 /path/to/prefix pnpm embedded-mpv:stage-runtime -- darwin x64 /path/to/prefix pnpm embedded-mpv:stage-runtime -- win32 x64 /path/to/prefix pnpm embedded-mpv:stage-runtime -- linux x64 /path/to/prefix ``` Build the pinned macOS or Linux source runtime first when no prefix exists: ```bash pnpm embedded-mpv:build-runtime -- arm64 /tmp/macos-prefix pnpm embedded-mpv:stage-runtime -- darwin arm64 /tmp/macos-prefix pnpm embedded-mpv:build-runtime:linux -- /tmp/linux-prefix pnpm embedded-mpv:stage-runtime -- linux x64 /tmp/linux-prefix ``` ### Windows CI pin lifecycle Windows package builds consume the one validated record in `windows-runtime-pin.json`; URL and checksum repository variables are not build inputs. Check it locally with: ```bash pnpm embedded-mpv:windows-runtime-pin:check ``` The weekly `refresh-windows-embedded-mpv-runtime.yaml` workflow opens a bot PR when the upstream asset is unavailable or 14 days old, well before zhongfly's 30-day retention boundary. A manual refresh uses the same dependency-free updater: ```bash pnpm embedded-mpv:windows-runtime-pin:refresh -- --force ``` The upstream archive is checksum- and layout-verified, not independently certified as a complete LGPL closure. It contains no corresponding source or license notices, so IPTVnator does not mirror it. Any future stable mirror must ship complete corresponding source, exact build scripts and patches, notices, and a validated transitive license record beside the binary. The macOS builder verifies every downloaded archive against its pinned SHA-256 digest before extraction. FreeType uses its official SourceForge distribution as the primary source and the official Savannah distribution as a fallback; a failed or mismatched download is discarded before the next mirror is attempted. The runtime manifest records the selected URL for a new download and the complete ordered candidate list for every archive, so fallback use remains visible in the source provenance. Changes to the downloader participate in the runtime cache key, so cached native artifacts cannot outlive source-acquisition policy changes. The Linux builder runs only on Linux x64. It requires the tool versions and system development interfaces declared in `build-linux-runtime.cjs`, including Meson 1.6 or newer, gperf 3.1 or newer, Ninja, CMake, NASM, pkg-config, patchelf, and `readelf`. It builds into an owned staging directory and publishes atomically, so it will not delete or overwrite an arbitrary destination. The Linux builder acquires its archives through the same `downloadPinnedSource` helper, so a pin whose primary host is unavailable falls through to its pinned `mirrors` before the build fails; every candidate is verified against the pinned SHA-256, and a mismatch is discarded rather than used. FreeType, Fontconfig, and libdisplay-info carry mirrors because their primary hosts are single points of failure — freedesktop.org in particular answers GitHub runners with HTTP 418 under load. Unlike the macOS manifest, the Linux manifest keeps `sourceUrl` at the canonical pinned value even when a mirror served the bytes: notice generation and the Snap publication boundary compare that field against the immutable pin. A used mirror is reported in the build log instead. `download-pinned-source.mjs` is part of the released source-archive tooling set and of the Linux runtime cache key. The pinned Linux source stack currently includes FFmpeg 8.1, mpv 0.41.0, libplacebo 7.360.1, libass 0.17.3, FreeType 2.13.3, FriBidi 1.0.16, HarfBuzz 8.5.0, Expat 2.8.2, Fontconfig 2.16.0, OpenSSL 3.5.7, hwdata 0.409, and libdisplay-info 0.1.1. The builder stages a private pinned `pnp.ids`/`hwdata.pc`; libdisplay-info is not allowed to consume the build host's `/usr/share/hwdata`. Before publication, the Linux builder verifies: - every archive digest and git/submodule commit; - the exact FFmpeg/mpv flags and LGPL policy; - an exact `libmpv.so.2` SONAME and complete reachable shared-library closure; - `$ORIGIN` RUNPATHs with no build-prefix paths or undeclared host fallback; - the external system-library allowlist; - `GLIBC_2.35` and `GLIBCXX_3.4.30` ABI ceilings; - file hashes, byte sizes, build inputs, licenses, and source obligations. ## Linux Package Profiles Set one exact `IPTVNATOR_LINUX_FRAME_COPY_PROFILE` per packaging pass: | Profile | Formats | Runtime handling | | ---------- | ---------------- | ---------------------------------------------------------------------------- | | `system` | DEB, RPM, Pacman | Remove `native/lib`; require the format-specific system runtime listed below | | `portable` | AppImage, Snap | Retain the pinned LGPL closure under `native/lib` | | `flatpak` | Flatpak | Retain the same pinned LGPL closure under `native/lib` | The system helper directly links libmpv, EGL, GL, and GBM. Package metadata therefore declares the full interface set: - DEB: `libmpv2`, `libegl1`, `libgl1`, `libgbm1` - RPM: `mpv-libs`, `libglvnd-egl`, `libglvnd-glx`, `mesa-libgbm` - Pacman: `mpv`, `libglvnd`, `mesa` The helper links `libGL.so.1` (`-lGL`) rather than `libOpenGL.so.0`; the former is the direct GL interface supplied by all three system contracts and Snap's `mesa-core22`. The DEB metadata is release-tested on Ubuntu 24.04 (Noble). Ubuntu 22.04 (Jammy) only provides `libmpv1`; use the x64 AppImage on that distribution rather than relaxing the runtime contract. CI explicitly installs the distro Mesa software renderer for headless smoke. IPTVnator does not add DRI-driver packages as direct dependencies; any transitive graphics-driver stack remains under the distro's dependency policy. The Snap is `base: core22` with strict confinement. It retains Electron Builder's default plugs and adds an auto-connected private `shared-memory` plug plus `graphics-core22`, targeting a real empty mode-0755 `$SNAP/graphics` with external `mesa-core22` as default provider. The graphics provider supplies EGL/GL/GLX/GBM/DRM/VA, while Electron Builder's exact GNOME content runtime supplies ALSA/PulseAudio. Neither provider is bundled into IPTVnator's Snap, source archive, notices, or package-size accounting. The package hook creates the empty content target because core22 does not synthesize one; the extracted artifact verifier rejects a missing, redirected, non-empty, or wrongly permissioned target. Snap metadata must also contain exactly the canonical graphics-provider layouts: bind `/usr/share/libdrm` from `$SNAP/graphics/libdrm`, and symlink `/usr/share/drirc.d` to `$SNAP/graphics/drirc.d`. The bounded probe and every playback helper share one sanitized loader environment derived from the validated, cached runtime mode. Ambient ELF audit/preload/origin/library overrides, direct EGL/GBM/GL/VA/Vulkan paths, shell startup/options, tracing hooks, exported Bash functions, and caller-provided architecture triplets are removed or replaced. The extracted-artifact verifier uses the same deny-set for its direct helper smoke and preserves feature/debug selectors such as `LIBGL_ALWAYS_SOFTWARE`. System packages then use the default loader; bundled packages put their validated `native/lib` first. Packaged addon/helper lookup is package-owned `app.asar.unpacked` only; cwd/dist candidates are development-only. AppImage and Flatpak use normal host/sandbox lookup for the declared external interfaces. Inside the exact packaged Flatpak `/app` context, the helper reconstructs only Freedesktop Platform 24.08's immutable `__EGL_EXTERNAL_PLATFORM_CONFIG_DIRS` value; the GL extension's `add-ld-path` remains available through the sandbox loader cache. Flatpak CI therefore invokes `flatpak run com.fourgray.iptvnator --embedded-mpv-runtime-probe` instead of executing the helper around the application gate. In a genuine Snap mount, filtered `SNAP_LIBRARY_PATH` GL roots under `/var/lib/snapd/lib/gl` come next, then the fixed x64 `$SNAP/graphics` roots, then the core22 base `/usr/lib/x86_64-linux-gnu`, exact `$SNAP/gnome-platform` graphics/audio roots, and finally generic `$SNAP` library roots. Keeping the base ABI ahead of the older GNOME content runtime prevents its `libedit.so.2` from injecting an unavailable `libtinfo.so.5` dependency into mesa-core22's software renderer. The helper rebuilds GBM, GL/VA driver, EGL vendor/platform, and Vulkan layer variables from those trusted locations. A Linux session without the validated cached mode is rejected before spawn. Both the bounded probe and playback execute through `$SNAP/graphics/bin/graphics-core22-provider-wrapper`. The graphics mount must be a real directory and the wrapper a regular, non-symlinked, readable executable. Otherwise the gate returns the stable `snap-graphics-provider-unavailable` reason before spawning the helper. The wrapper child also drops shell startup/options, tracing hooks, and exported `BASH_FUNC_*` functions, and uses a fixed core22 system `PATH`; ambient Bash configuration therefore cannot replace the probe before helper execution. Installed-Snap CI disconnects `graphics-core22`, requires the application-level diagnostic to emit `snap-graphics-provider-unavailable` and exit with the controlled status `1`, then reconnects the provider and requires a successful diagnostic. This keeps the canonical layouts and missing-provider fallback in the same regression contract. Flatpak is an isolated packaging pass and keeps `iptvnator` as the real Electron ELF so Electron Builder's `electron-wrapper` passes it directly to Zypak. Other Linux targets retain the conditional `iptvnator` wrapper and `iptvnator.bin`. Mixed Flatpak/non-Flatpak target sets fail before mutation. A missing or unsupported profile, or a target from another profile, fails packaging. Linux frame-copy release artifacts are x64-only. Non-x64 packages are always marker-only even if environment variables point at the x64 staged runtime. ## Build Integration `apps/electron-backend/build-embedded-mpv.js` builds the addon, frame reader, and helper against the staged inputs. On Linux it links the helper to the verified staged libmpv path rather than a generic host `-lmpv`, then checks with `readelf` that: - the helper has exactly the declared libmpv `DT_NEEDED`; - the helper RUNPATH is `$ORIGIN/lib`; - the addon and frame reader have no libmpv dependency; - no runtime dependency contains an absolute/build-prefix loader path. The package hook copies native artifacts into `app.asar.unpacked/electron-backend/native/`, selects the system or bundled layout, restores exact file modes, writes the packaged manifest, and validates the bundled legal payload. AppImage, Snap, and Flatpak receive `embedded-mpv-notices.json`, `THIRD_PARTY_NOTICES.txt`, and `licenses//**`; DEB, RPM, Pacman, and marker-only packages must not retain them. Package validation also scans the Electron executable and all shipped Electron libraries for a direct libmpv dependency. Before target packaging, that scan is recursive over the pristine Electron tree. After Snap has merged its template runtime into the payload root, the post-target scan excludes exactly its package-manager `lib/**` and `usr/lib/**` trees while remaining recursive everywhere else. At startup, Linux x64 frame-copy is advertised only after the main process validates that manifest/files and successfully executes: ```bash iptvnator_mpv_helper --runtime-probe ``` The bounded probe initializes idle libmpv plus EGL/OpenGL and mpv render contexts, then creates, maps, validates, and destroys a minimal `16x16` shared-memory ring named `/impv-fc-runtime-probe-`. It does not open media or enter media/command loops. A timeout, loader failure, malformed protocol, missing file, hash mismatch, unusable graphics path, or shm lifecycle failure returns a stable reason and keeps the BrowserWindow sandbox enabled. The application diagnostic retains `helper-probe-failed` as the top-level reason for nonzero helper exits and adds `helperReason` only when the helper emitted one exact protocol-v1 line with a fixed allowlisted reason. Its optional `helperDetail` is restricted to 1–1024 printable ASCII characters; invalid detail suppresses both helper fields. Every probe has the same explicit 16 MiB aggregate captured-output ceiling, regardless of tracing. With `IPTVNATOR_TRACE_PLAYER=1`, non-empty captured helper stderr is written separately as one JSON-escaped stderr line: its `stderr` field contains at most the first 16,384 characters and its `truncated` boolean is always explicit. Empty captures, disabled tracing, and trace-writer failures do not emit a record or alter availability. The installed-Snap probe therefore tests the private shared-memory confinement needed by playback rather than only loader and graphics startup. Packaging CI invokes the same gate through `snap run iptvnator --embedded-mpv-runtime-probe`. This packaging-only application switch runs before BrowserWindow startup, emits one availability JSON line, and returns zero only for a usable runtime; it never directly loads libmpv in Electron. The installed-Snap smoke adds `EGL_LOG_LEVEL=debug` and `LIBGL_DEBUG=verbose` under that bounded trace channel to expose GLVND/Mesa loader failures without weakening the hostile-environment gate. Electron Builder excludes `electron-backend/native{,/**/*}` from `app.asar`. Only `afterPack` writes the profile-normalized `app.asar.unpacked/electron-backend/native` tree. Layout and final-artifact verification enumerate `app.asar` and reject any stale native entry, preventing hidden x64 helpers, bundled libraries, or notices in system and marker-only packages. ## CI And Source Distribution Linux CI builds or restores the pinned source runtime once, then packages and verifies `system`, `portable`, and `flatpak` independently. Every artifact is extracted for manifest, mode, package-metadata, ELF-isolation, and helper-probe checks. System formats are probed after their declared dependency is installed; Snap and Flatpak also require a sandboxed probe where the runner supports it. `tools/packaging/verify-linux-frame-copy-runtime.mjs` bounds its helper probe at `PACKAGE_VERIFICATION_PROBE_TIMEOUT_MS` (15 s), not the application gate's `RUNTIME_PROBE_TIMEOUT_MS` (3 s): the short budget exists because the app's decision blocks the Electron main process, whereas nothing waits on the packaging probe but the CI job's own timeout, and a premature kill would call a healthy package broken. A hard timeout is the one outcome that says nothing about the payload, so the verifier repeats it up to `PACKAGE_VERIFICATION_PROBE_MAX_ATTEMPTS` (2) times with the identical bounded launch and announces the retry on stderr. Every other outcome — spawn error, signal, nonzero exit, malformed protocol line — stays fail-closed on the first attempt, and a helper that keeps hanging still fails once the attempts are spent. Both constants live in `runtime-probe-contract.cjs`. For a locally installed `--dangerous` Snap, CI explicitly installs and connects `mesa-core22` and `gnome-3-28-1804`, verifies both connections, and then runs the application-level diagnostic under Xvfb. The Linux packaging matrix alone depends on the runtime-builder job. macOS and Windows use an independent matrix, while both matrices share the same anchored step list; draft release assembly remains atomic and requires both matrices. The Linux runtime cache contains only staged headers/libraries/manifest plus immutable source inputs: exact downloaded archives (including hwdata), a clean recursive libplacebo checkout, and collected license files. It never caches finished notices or the compliance tarball. After either a build or cache hit, CI revalidates those inputs, regenerates `vendor/embedded-mpv/linux-x64/notices` for the current runtime manifest, and creates `linux-frame-copy-runtime-sources.tar.xz` for the current repository revision/diff. Before archiving, the clean cached libplacebo checkout is converted into a non-dereferenced working-tree snapshot with every `.git` entry removed; the validated main/submodule commits remain in the source index. That source-compliance archive uses normalized tar metadata and contains the exact unique archive hash set, VCS-free libplacebo sources and the exact pinned six recursive submodule records, license inputs, generated notices, runtime/source index metadata, and the builder, stager, manifest, notice-generator, and source-snapshot code. Submodule identity is canonicalized as `full-commit safe/path`; optional clone-depth-dependent `git describe` annotations are discarded. The source index carries a globally sorted inventory of every libplacebo directory, file, and symlink. Regular-file hashes, sizes, normalized executable bits, exact safe link targets, aggregate counts/bytes, and the canonical inventory digest are checked against the trusted pinned v7.360.1 checkout. The tar has an exact member/type layout, and `metadata/archive-sha256.txt` is checked against the actual source archive bytes. Listing continues past every tar end marker so concatenated xz streams cannot hide undeclared members. The notice generator rejects missing, undeclared, symlinked, size-mismatched, or hash-mismatched license files. Once CI creates the final `linux-frame-copy-runtime-sources.tar.xz`, it writes `source-archive-binding.json` beside the staged runtime with the archive's SHA-256 and repository revision. Bundled x64 AppImage, Snap, and Flatpak manifests copy that exact object as `sourceArchive`; system packages and marker-only non-x64 packages omit it. The packaged x64 Playwright smoke depends on its fixture-contract target and passes Chromium `--ignore-gpu-blocklist` so Mesa llvmpipe can provide WebGL2 in CI. This affects only Chromium's software-renderer admission; the manifest, hash, loader, and helper probes still fail closed, and `--no-sandbox` remains root-only. Snap publication is a separate `release.published` workflow for public `v*` GitHub releases. It verifies that the public release already contains at least one Snap and exactly one non-empty `linux-frame-copy-runtime-sources.tar.xz` before uploading anything. The release verifier hashes the downloaded archive, checks its clean released revision, exact member/type layout and safe link targets, source checksum metadata, source index, actual pinned source-member hashes, six recursive libplacebo submodule records, legal payload, exact trusted libplacebo tree inventory/digest, released tooling, and runtime manifest. Checkout and both artifact-transfer actions use full pinned commits, and checkout does not persist its repository credential. The verifier bounds source members, the archive, SquashFS listing, extracted size, entry count, command time, and job time; every Snap must use the canonical `/usr/lib/iptvnator` layout and pass the existing static package validator. The public-release boundary also reapplies the exact strict `meta/snap.yaml` graphics/shared-memory/layout contract and enumerates the extracted `resources/app.asar`, rejecting any archived `electron-backend/native/**` payload. Its bounded ASAR header reader depends only on Node built-ins and released local tooling, so verification remains runnable in the clean tag checkout without `node_modules`. Exactly one x64 Snap is accepted, and only when its exact `sourceArchive` and `sourceRuntime` match the downloaded archive; any non-x64 Snap must be marker-only. A secretless job copies each asset through a no-follow descriptor, checks hashes before and after inspection, writes an exact receipt, fully reverifies a root-owned read-only snapshot, and transfers only that data through the pinned artifact service while publishing the exact receipt digest separately as a job output. The dependent publish job runs on a bounded GitHub-hosted `ubuntu-latest` runner with no checkout or release-tag code. It verifies that separate digest, the exact receipt schema, every asset size/hash, and the expected regular-file layout, rejects links and extras, root-seals the transferred data again, and installs the official stable Snapcraft snap. Only its final fixed shell step receives the Store credential; it executes no released code, resolves no PATH command, and passes the credential only to each exact `/snap/bin/snapcraft upload --release=edge` process. GitHub credentials remain scoped to asset selection/download. Candidate/stable promotion is manual after installed-Snap frame-copy and missing-runtime fallback smoke; GitHub Actions never promotes automatically. Windows CI stages the x64 LGPL archive selected by the checked-in validated pin described above. PR, master, and tag builds consume that same record; repository variables and fallback URLs are not build inputs. The DLL basename encoded in the archive's import library is preserved and must be present beside `iptvnator_mpv_helper.exe`. The weekly workflow rotates the reviewed pin before the upstream's latest-30-build retention removes it. A permanent mirror still requires the complete corresponding source/build records, license notices, and validated transitive license closure beside the binary. ## Local Development Linux can use distribution development packages for an unshipped local build (`libmpv-dev`, EGL/GL/GBM development files, and X11 headers). Overrides: `LIBMPV_INCLUDE_DIR` selects the header root. `LINUX_NATIVE_LIBRARY_DIR` selects a link-time library directory that must already be visible to the system dynamic loader; it is not inherited as a helper `LD_LIBRARY_PATH`. Required/release package builds must use the pinned staged runtime and manifest. On macOS: ```bash pnpm run serve:backend:embedded-mpv ``` This explicitly permits Homebrew for the local native build and enables the experiment. It is not a release path. See `docs/architecture/embedded-mpv-native.md` for the runtime capability, fallback, controls, and packaged-release contracts.