$NetBSD: patch-openbsd-compat_memrchr.c,v 1.1 2018/04/06 22:21:42 hubertf Exp $

--- openbsd-compat/memrchr.c.orig	2018-04-05 19:37:00.000000000 +0000
+++ openbsd-compat/memrchr.c
@@ -0,0 +1,41 @@
+/*
+ * Copyright (c) 2007 Todd C. Miller <Todd.Miller@courtesan.com>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include <config.h>
+
+#include <sys/types.h>
+
+/*
+ * Reverse memchr()
+ * Find the last occurrence of 'c' in the buffer 's' of size 'n'.
+ */
+void *
+memrchr(s, c, n)
+    const void *s;
+    int c;
+    size_t n;
+{
+    const unsigned char *cp;
+
+    if (n != 0) {
+	cp = (unsigned char *)s + n;
+	do {
+	    if (*(--cp) == (unsigned char)c)
+		return (void *)cp;
+	} while (--n != 0);
+    }
+    return (void *)0;
+}