rootfs: build for the host architecture

debootstrap arch and the vm-guest musl target now follow uname -m
(amd64/x86_64 alongside the existing arm64/aarch64 path).

Co-authored-by: Hanzo Dev <[email protected]>

scripts/prepare-rootfs.sh

@@ -13,12 +13,19 @@ DEBIAN_RELEASE="trixie"
 DATA_DIR="${HANZO_VM_HOME:-$HOME/.hanzo/vm}"
 SCRIPT_DIR="$(cd "$(dirname "$0")" && pwd)"
 REPO_DIR="$(dirname "$SCRIPT_DIR")"
-GUEST_BINARY="${REPO_DIR}/target/aarch64-unknown-linux-musl/release/vm-guest"
 ROOTFS_SIZE_MB=1024
 
+# The guest image is built for the host architecture (macOS builds arm64
+# in a container below).
+case "$(uname -m)" in
+    x86_64) GUEST_TARGET="x86_64-unknown-linux-musl"; DEB_ARCH="amd64" ;;
+    *)      GUEST_TARGET="aarch64-unknown-linux-musl"; DEB_ARCH="arm64" ;;
+esac
+GUEST_BINARY="${REPO_DIR}/target/${GUEST_TARGET}/release/vm-guest"
+
 if [ ! -f "$GUEST_BINARY" ]; then
     echo "ERROR: guest binary not found at ${GUEST_BINARY}"
-    echo "       Run: cargo build -p vm-guest --target aarch64-unknown-linux-musl --release"
+    echo "       Run: cargo build -p vm-guest --target ${GUEST_TARGET} --release"
     exit 1
 fi
 
@@ -31,11 +38,6 @@ if [ "$(uname)" = "Darwin" ]; then
         "debian:${DEBIAN_RELEASE}-slim" /src/scripts/prepare-rootfs.sh
 fi
 
-if [ "$(uname -m)" != "aarch64" ]; then
-    echo "ERROR: the guest is aarch64; build on an arm64 Linux host"
-    exit 1
-fi
-
 SUDO=""
 [ "$(id -u)" = 0 ] || SUDO=sudo
 
@@ -96,7 +98,7 @@ if [ -f "${DATA_DIR}/rootfs.ext4" ]; then
 else
     echo "==> Building Debian ${DEBIAN_RELEASE} rootfs (${ROOTFS_SIZE_MB}MB)..."
     ROOT="${WORK}/rootfs"
-    $SUDO debootstrap --arch=arm64 --variant=minbase "$DEBIAN_RELEASE" "$ROOT" http://deb.debian.org/debian
+    $SUDO debootstrap --arch="$DEB_ARCH" --variant=minbase "$DEBIAN_RELEASE" "$ROOT" http://deb.debian.org/debian
 
     $SUDO mkdir -p "${ROOT}/etc/dpkg/dpkg.cfg.d"
     cat <<'DPKG' | $SUDO tee "${ROOT}/etc/dpkg/dpkg.cfg.d/01-nodoc" > /dev/null