Enhance build script to utilize a configuration template for BusyBox and improve installation logic. Added checks for the presence of the config template and updated installation steps for shared libraries.

build.sh

@@ -21,6 +21,7 @@ BUSYBOX_DIR="${SCRIPT_DIR}/busybox"
 SYSROOT_DEFAULT="/home/stargazer/arm-uclinuxfdpiceabi/sysroot"
 SYSROOT="${1:-${SYSROOT:-$SYSROOT_DEFAULT}}"
 ENV_FILE="${ENV_FILE:-${SCRIPT_DIR}/env.sh}"
+CONFIG_TEMPLATE="${SCRIPT_DIR}/config/.config"
 
 die() {
   echo "ERROR: $*" >&2
@@ -55,19 +56,22 @@ echo "Strip: ${STRIP_BIN}"
 echo "SYSROOT: ${SYSROOT}"
 echo "Source dir: ${BUSYBOX_DIR}"
 echo "Install dir: ${INSTALL_DIR}"
+echo "Config template: ${CONFIG_TEMPLATE}"
+
+if [ ! -f "${CONFIG_TEMPLATE}" ]; then
+  die "Config template not found: ${CONFIG_TEMPLATE}"
+fi
 
 cd "${BUSYBOX_DIR}"
 
-if [ ! -f ".config" ]; then
-  make defconfig
-fi
+cp "${CONFIG_TEMPLATE}" .config
 
 # Force BusyBox shared library build profile.
 if [ -x "./scripts/config" ]; then
   ./scripts/config \
     -e BUILD_LIBBUSYBOX \
     -e FEATURE_SHARED_BUSYBOX \
-    -e FEATURE_INDIVIDUAL \
+    -d FEATURE_INDIVIDUAL \
     -d STATIC \
     -d PIE \
     -d FEATURE_LIBBUSYBOX_STATIC
@@ -84,13 +88,27 @@ make -j"${JOBS}" \
   EXTRA_LDFLAGS="--sysroot=${SYSROOT}"
 
 make CONFIG_PREFIX="${INSTALL_DIR}" install
-if [ -f "busybox" ]; then
-  "${STRIP_BIN}" busybox
-fi
-if [ -f "libbusybox.so" ]; then
-  "${STRIP_BIN}" libbusybox.so
+
+# If FEATURE_SHARED_BUSYBOX/BUILD_LIBBUSYBOX are enabled, BusyBox also
+# produces a tiny launcher in 0_lib/ that links against libbusybox.
+# Install that pair instead of the monolithic ./busybox to actually save space.
+if [ -f "0_lib/busybox" ]; then
+  install -D -m 0755 "0_lib/busybox" "${INSTALL_DIR}/bin/busybox"
 fi
 
+# Install the exact SONAME that the launcher needs (e.g. libbusybox.so.1.31.1)
+shopt -s nullglob
+libbusybox_candidates=(0_lib/libbusybox.so.*)
+shopt -u nullglob
+for f in "${libbusybox_candidates[@]}"; do
+  case "${f}" in
+    *_unstripped*|*.map|*.out) continue ;;
+  esac
+  install -D -m 0755 "${f}" "${INSTALL_DIR}/lib/$(basename "${f}")"
+  # Optional convenience symlink (not required at runtime).
+  ln -sf "$(basename "${f}")" "${INSTALL_DIR}/lib/libbusybox.so" 2>/dev/null || true
+done
+
 echo "Build completed successfully."
 echo "Binary: ${BUSYBOX_DIR}/busybox"
 echo "Shared library: ${BUSYBOX_DIR}/libbusybox.so"