Add build tagging and rtl8139 network card kernel drivers

board/mentalnet/post-build.sh

@@ -0,0 +1,32 @@
+#!/bin/sh
+#
+# post-build.sh - stamp the Mentalnet root filesystem with a build id
+#
+# Invoked by Buildroot (BR2_ROOTFS_POST_BUILD_SCRIPT) with the target
+# directory as first argument. The same stamp is recorded in
+# output/images/.mn-build-stamp so post-image.sh can name the ISO
+# after the exact build that is inside it.
+#
+# The stamp is visible inside the guest:
+#   - /etc/os-release  -> BUILD_ID="YYYYMMDD-HHMMSS"
+#   - /etc/issue       -> shown above the login prompt
+
+set -e
+
+TARGET_DIR="${1}"
+STAMP="$(date +%Y%m%d-%H%M%S)"
+IMAGES_DIR="$(dirname "${TARGET_DIR}")/images"
+
+# record the stamp for post-image.sh
+mkdir -p "${IMAGES_DIR}"
+echo "${STAMP}" > "${IMAGES_DIR}/.mn-build-stamp"
+
+# /etc/os-release (regular file lives at /usr/lib/os-release)
+OS_RELEASE="${TARGET_DIR}/usr/lib/os-release"
+sed -i '/^BUILD_ID=/d' "${OS_RELEASE}"
+echo "BUILD_ID=\"${STAMP}\"" >> "${OS_RELEASE}"
+
+# login banner
+ISSUE="${TARGET_DIR}/etc/issue"
+sed -i '/^Mentalnet GNU\/Linux build /d' "${ISSUE}"
+printf 'Mentalnet GNU/Linux build %s\n' "${STAMP}" >> "${ISSUE}"