V8.03.768.2025.06.23

Signed-off-by: Marc S. Weidner <msw@coresecret.dev>

lib/lib_guard_sourcing.sh

@@ -0,0 +1,42 @@
+#!/bin/bash
+# SPDX-Version: 3.0
+# SPDX-CreationInfo: 2025-05-05; WEIDNER, Marc S.; <msw@coresecret.dev>
+# SPDX-ExternalRef: GIT https://git.coresecret.dev/msw/CISS.debian.live.builder.git
+# SPDX-FileContributor: WEIDNER, Marc S.; Centurion Intelligence Consulting Agency
+# SPDX-FileCopyrightText: 2024-2025; WEIDNER, Marc S.; <msw@coresecret.dev>
+# SPDX-FileType: SOURCE
+# SPDX-License-Identifier: EUPL-1.2 OR LicenseRef-CCLA-1.0
+# SPDX-LicenseComment: This file is part of the CISS.hardened.installer framework.
+# SPDX-PackageName: CISS.debian.live.builder
+# SPDX-Security-Contact: security@coresecret.eu
+
+#######################################
+# Prevent the caller LIB-file from being sourced twice.
+# Derive a safe guard-variable name from the caller script filename.
+# Globals:
+#   BASH_SOURCE
+# Arguments:
+#   $1: Explicitly provided Argument: filename of the caller LIB. (Better let the guard_sourcing() determine dynamically.
+# Returns:
+#   0: Returns '0' in both cases as they are intended to be successful.
+#######################################
+guard_sourcing() {
+  ### Determine the caller script (the library being sourced).
+  declare var_src="${1:-${BASH_SOURCE[1]}}"
+  ### Strip path, keep only filename
+  declare var_file_name="${var_src##*/}"
+  ### Sanitize to valid var name.
+  declare var_safe_name="${var_file_name//[^a-zA-Z0-9_]/_}"
+  ### Build guard-variable name.
+  declare var_guard_var="_${var_safe_name}_LOADED"
+
+  ### If already loaded, abort sourcing
+  if [[ -n "${!var_guard_var:-}" ]]; then
+    return 0
+  fi
+
+  ### Mark as loaded (readonly + exported)
+  declare -grx "${var_guard_var}"=1
+  return 0
+}
+# vim: number et ts=2 sw=2 sts=2 ai tw=128 ft=sh