--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/xmalloc.h	Tue Dec 06 13:51:55 2022 +0000
@@ -0,0 +1,41 @@
+/* $OpenBSD: xmalloc.h,v 1.2 2016/11/17 10:06:08 nicm Exp $ */
+
+/*
+ * Author: Tatu Ylonen <ylo@cs.hut.fi>
+ * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
+ *                    All rights reserved
+ * Created: Mon Mar 20 22:09:17 1995 ylo
+ *
+ * Versions of malloc and friends that check their results, and never return
+ * failure (they call fatal if they encounter an error).
+ *
+ * As far as I am concerned, the code I have written for this software
+ * can be used freely for any purpose.  Any derived versions of this
+ * software must be clearly marked as such, and if the derived work is
+ * incompatible with the protocol description in the RFC file, it must be
+ * called by a name other than "ssh" or "Secure Shell".
+ */
+
+#ifndef XMALLOC_H
+#define XMALLOC_H
+
+void	*xmalloc(size_t);
+void	*xcalloc(size_t, size_t);
+void	*xrealloc(void *, size_t);
+void	*xreallocarray(void *, size_t, size_t);
+char	*xstrdup(const char *);
+char	*xstrndup(const char *, size_t);
+int	 xasprintf(char **, const char *, ...)
+		__attribute__((__format__ (printf, 2, 3)))
+		__attribute__((__nonnull__ (2)));
+int	 xvasprintf(char **, const char *, va_list)
+		__attribute__((__nonnull__ (2)));
+int	 xsnprintf(char *, size_t, const char *, ...)
+		__attribute__((__format__ (printf, 3, 4)))
+		__attribute__((__nonnull__ (3)))
+		__attribute__((__bounded__ (__string__, 1, 2)));
+int	 xvsnprintf(char *, size_t, const char *, va_list)
+		__attribute__((__nonnull__ (3)))
+		__attribute__((__bounded__ (__string__, 1, 2)));
+
+#endif	/* XMALLOC_H */