WIP: Introduce libcryptsetup_cli.

Introducing new library supposed to be used in
cryptsetup tools and future cryptsetup loadable plugins

TODO:
  - distribution
  - cleanup header files
  - incorporate also plugin API?

lib/cli/cli_internal.h

@@ -0,0 +1,50 @@
+/*
+ * libcryptsetup_cli - cryptsetup command line tools library
+ *
+ * Copyright (C) 2012-2020 Red Hat, Inc. All rights reserved.
+ * Copyright (C) 2012-2020 Milan Broz
+ * Copyright (C) 2020 Ondrej Kozina
+ *
+ * This file is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This file is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this file; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#ifndef CLI_INTERNAL_H
+#define CLI_INTERNAL_H
+
+#include <stdbool.h>
+#include <sys/types.h>
+
+#define MAX_ACTIONS 16
+
+struct tools_arg {
+	const char *name;
+	bool set;
+	crypt_arg_type_info type;
+	union {
+		char *str_value;
+		uint64_t u64_value;
+		uint32_t u32_value;
+		int32_t i32_value;
+		int64_t i64_value;
+	} u;
+	const char *actions_array[MAX_ACTIONS];
+};
+
+struct crypt_cli {
+	const struct tools_arg *core_args;
+	size_t core_args_count;
+};
+
+#endif