07c22ccd39
uid may be shared by other apps (e.g., in MIUI, systemui's uid is 1000 and shared by many system apps).
Native Development
Prerequisite
Install the NDK required to build and develop Magisk with ./build.py ndk. The NDK will be installed to $ANDROID_SDK_ROOT/ndk/magisk. You don't need to manually install a Rust toolchain with rustup, as the NDK installed already has a Rust toolchain bundled.
Build Configs
All C/C++ code and its dependencies are built with ndk-build and configured with several *.mk files scattered in many places.
The src folder is also a proper Cargo workspace, and all Rust code is built with cargo just like normal Rust projects.
Rust + C/C++
To reduce complexity involved in linking, all Rust code is built as staticlib and linked to C++ targets to ensure our final product is built with an officially supported NDK build system. Each C++ target can at most link to one Rust staticlib or else multiple definitions error will occur.
We use the cxx project for Rust and C++ interop.
Development / IDE
All C++ code should be recognized and properly indexed by Android Studio out of the box. For Rust:
- Install the Rust plugin in Android Studio
- In Preferences > Languages & Frameworks > Rust, set
$ANDROID_SDK_ROOT/ndk/magisk/toolchains/rust/binas the toolchain location - Open
native/src/Cargo.toml, and select "Attach" in the "No Cargo projects found" banner
Note: run ./build.py binary before developing to make sure generated code is created.