1 files changed, 37 insertions, 0 deletions
diff --git a/libpam/include/pam_inline.h b/libpam/include/pam_inline.h
new file mode 100644
index 00000000..d93f8474
--- /dev/null
+++ b/libpam/include/pam_inline.h
@@ -0,0 +1,37 @@
+/*
+ * Copyright (c) 2020 Dmitry V. Levin <ldv@altlinux.org>
+ *
+ * Handy inline functions and macros providing some convenient functionality
+ * to libpam and its modules.
+ */
+
+#ifndef PAM_INLINE_H
+#define PAM_INLINE_H
+
+#include "pam_cc_compat.h"
+
+/*
+ * Evaluates to
+ * - a syntax error if the argument is 0,
+ * 0, otherwise.
+ */
+#define PAM_FAIL_BUILD_ON_ZERO(e_)	(sizeof(int[-1 + 2 * !!(e_)]) * 0)
+
+/*
+ * Evaluates to
+ * 1, if the given type is known to be a non-array type
+ * 0, otherwise.
+ */
+#define PAM_IS_NOT_ARRAY(a_)		PAM_IS_SAME_TYPE((a_), &(a_)[0])
+
+/*
+ * Evaluates to
+ * - a syntax error if the argument is not an array,
+ * 0, otherwise.
+ */
+#define PAM_MUST_BE_ARRAY(a_)		PAM_FAIL_BUILD_ON_ZERO(!PAM_IS_NOT_ARRAY(a_))
+
+/* Evaluates to the number of elements in the specified array.  */
+#define PAM_ARRAY_SIZE(a_)		(sizeof(a_) / sizeof((a_)[0]) + PAM_MUST_BE_ARRAY(a_))
+
+#endif /* PAM_INLINE_H */