Building

Building from source

Three artifacts: the native daemon, the helper APK, and the Magisk module zip that bundles both.

Requirements

Component	Purpose	Where to get it
Android NDK r21+	cross-compile torchd for arm64/arm/x86/x86_64	brew install --cask android-ndk
Android cmdline-tools (build-tools 34+, platform-34+)	build the APK without Gradle	brew install --cask android-commandlinetools
JDK 11+	javac, keytool	system or brew install openjdk
zip, bash, make	standard	preinstalled on macOS / Linux
adb (optional)	deploy to device	brew install --cask android-platform-tools

Verified on macOS 14 (Apple Silicon) and should work on Linux unchanged.

Layout

All build outputs and intermediates land under dist/ — the source tree stays clean.

dist/
├── bin/                       ← goes inside the Magisk module zip
│   ├── TorchButton.apk
│   ├── arm64-v8a/torchd
│   ├── armeabi-v7a/torchd
│   ├── x86/torchd
│   └── x86_64/torchd
├── torchbutton-vX.Y.Z.zip     ← Magisk-installable module
├── .obj/                      ← ndk-build intermediates (.o, .d)
└── .apk-build/                ← javac/d8/aapt2 intermediates

1. Native daemon (torchd)

export ANDROID_NDK_HOME=/path/to/android-ndk
./src/build.sh

build.sh searches $ANDROID_NDK_HOME, $NDK, and the usual install paths (~/Library/Android/sdk/ndk-bundle, ~/Android/Sdk/ndk/*, /opt/android-ndk). It runs ndk-build with src/Android.mk and src/Application.mk and writes binaries to dist/bin/<abi>/torchd.

file dist/bin/arm64-v8a/torchd
# ELF 64-bit LSB pie executable, ARM aarch64, ..., dynamically linked

2. Helper APK

Needed when the device has no writable sysfs torch node (Pixel/Tensor, where the flash is exclusively owned by the Camera HAL). When sysfs works the daemon runs without the APK; bundling it anyway is harmless — backend choice is automatic.

./apk/build.sh

Pipeline (no Gradle): aapt2 compile → aapt2 link → javac → d8 → zipalign → apksigner. Signed with a self-generated debug key (apk/.debug.keystore, created on first build). Output: dist/bin/TorchButton.apk.

Smoke test:

adb install -r dist/bin/TorchButton.apk
adb shell 'am broadcast -a me.nogrep.torchbutton.SET --es state on \
   -p me.nogrep.torchbutton --include-stopped-packages'
# Flashlight should turn on.
adb shell 'am broadcast -a me.nogrep.torchbutton.SET --es state off \
   -p me.nogrep.torchbutton --include-stopped-packages'

3. Module zip

./package.sh
# -> dist/torchbutton-vX.Y.Z.zip

package.sh reads dist/bin/ and produces the final zip. No META-INF is included — Magisk Manager injects its own installer template.