Dockerfile.cross

# Dockerfile for cross-compiling HyperCalibrate for Raspberry Pi
# Supports both aarch64 (64-bit) and armv7 (32-bit) targets

# Pin to Rust 1.85 on Bookworm - needed for home crate edition2024
# rust:latest requires glibc 2.39+ which is newer than Raspberry Pi OS (glibc 2.36)
FROM rust:1.85-bookworm

# Install cross-compilation tools, cmake, and libclang for bindgen
# g++-aarch64-linux-gnu is needed for turbojpeg-sys (libjpeg-turbo)
RUN apt-get update && apt-get install -y \
    gcc-aarch64-linux-gnu \
    g++-aarch64-linux-gnu \
    gcc-arm-linux-gnueabihf \
    g++-arm-linux-gnueabihf \
    libc6-dev-arm64-cross \
    libc6-dev-armhf-cross \
    pkg-config \
    cmake \
    nasm \
    clang \
    libclang-dev \
    && rm -rf /var/lib/apt/lists/*

# Add Rust targets for Raspberry Pi
RUN rustup target add aarch64-unknown-linux-gnu \
    && rustup target add armv7-unknown-linux-gnueabihf

# Create cargo config for cross-compilation
RUN mkdir -p /root/.cargo && \
    echo '[target.aarch64-unknown-linux-gnu]\n\
linker = "aarch64-linux-gnu-gcc"\n\
\n\
[target.armv7-unknown-linux-gnueabihf]\n\
linker = "arm-linux-gnueabihf-gcc"' > /root/.cargo/config.toml

WORKDIR /app

# Default to 64-bit build (Raspberry Pi 5 is 64-bit)
ENV TARGET=aarch64-unknown-linux-gnu

# Build command with target CPU optimization for RPi5 (Cortex-A76)
CMD ["sh", "-c", "RUSTFLAGS='-C target-cpu=cortex-a76' cargo build --release --target $TARGET && cp target/$TARGET/release/hypercalibrate /output/"]