dtourolle
cc1c5c892d
Correcting the previous commit: I claimed VFS placeholders could not be
downloaded. That was wrong. The desktop client exposes a socket at
$XDG_RUNTIME_DIR/Nextcloud/socket speaking newline-delimited
COMMAND:argument, and MAKE_AVAILABLE_LOCALLY:<path> does fetch the file.
Verified against client 4.0.7: a 1-byte stub became a real 2.8MB file in
2.8 seconds.
Implemented as dr-sync-nextcloud::desktop_client, deliberately optional.
Android has no desktop client, no XDG_RUNTIME_DIR socket and no
placeholders, so detect() returns None there and callers fall back to the
connector. It earns its place only because it is ~30 lines with no
dependencies: where a library already lives in a VFS folder, asking the
client to fetch beats downloading a second copy over WebDAV and leaving
the client's placeholder state inconsistent.
What this does not change: hydration is whole-file, so it suits the
original tier and never browsing. Filling a grid this way downloads the
entire library. Range extraction remains the only mechanism satisfying
FR-NC-3, and ARCH §9.0 now says so precisely.
Also fixes two real Android build failures found by cross-compiling:
- reqwest's `rustls` feature defaults to aws-lc-rs, whose aws-lc-sys
crate is C and fails under the NDK — exactly the pain D1 chose Rust
to avoid. Switched to rustls-no-provider + ring, installing the
provider in the constructor so no caller can build a client that
panics on first use.
- ring itself needs CC/AR per target; cargo-ndk sets only the linker.
Added them to the container.
87 tests passing. dr-sync-nextcloud cross-compiles for aarch64-linux-android.
Android build environment
Reproducible container for cross-compiling DarkRoom to Android. CI and local builds use the same image, so a break appears in one place rather than two.
Use
# Cross-compile for a device ABI
./docker/android/build.sh cargo ndk -t arm64-v8a build --release
# All four ABIs
./docker/android/build.sh cargo ndk -t arm64-v8a -t armeabi-v7a -t x86_64 -t x86 build --release
# Type-check without linking
./docker/android/build.sh cargo check --target aarch64-linux-android
# Interactive shell
./docker/android/build.sh
# After editing the Dockerfile
./docker/android/build.sh --rebuild
Prefers podman, falls back to docker. First run builds the image, which takes several minutes;
after that it is cached.
Pinned versions
| Component | Version | Why this one |
|---|---|---|
| JDK | 17 | AGP's stable target. The host's JDK 25 breaks Gradle. |
| Compile SDK | API 36 | Required for Play distribution |
| Min API | 28 (Android 9) | Floor where Vulkan support is dependable (NFR-COMPAT-1) |
| Build tools | 36.0.0 | Matches compile SDK |
| NDK | 27.2.12479018 (r27c) | Current LTS |
| Rust | 1.92.0 | Slint 1.17 requires it; cargo-ndk 4.1.x needs ≥ 1.86 |
| cargo-ndk | 4.1.2 |
Bumping any of these is a reviewable change, not silent drift.
Compile SDK versus min API
These are different and both matter. ANDROID_API (36) is what the SDK compiles against — the
newest APIs available. MIN_API (28) is what native code links against, and determines the
oldest device that can run the result.
cargo-ndk defaults to API 21 if not told otherwise, which is far below what this app needs.
CARGO_NDK_PLATFORM and the per-target linker paths both pin it to MIN_API. Verify with:
file target/aarch64-linux-android/release/*.so
# → "... for Android 28, built by NDK r27c"
Caching
The cargo registry and target directory persist in ~/.cache/darkroom-android, so rebuilds do not
re-download the crate index. Clear with:
rm -rf ~/.cache/darkroom-android
The Android target dir is kept separate from the host's target/ — sharing one directory between
host and container builds causes constant rebuilds as they invalidate each other's fingerprints.
What is not here
No emulator, no adb device access. This image cross-compiles; it does not run or deploy. Device
testing (spikes S2 and S10, which need two GPU vendors) happens on real hardware — the emulator's
GPU behaviour is not representative of Adreno or Mali, which is precisely what those spikes exist
to test.