https://github.com/WayneD/rsync/issues/324
https://github.com/WayneD/rsync/commit/3592ac3c025da23b2dd291561ec6113940b9c11b

From 3592ac3c025da23b2dd291561ec6113940b9c11b Mon Sep 17 00:00:00 2001
From: Wayne Davison <wayne@opencoder.net>
Date: Sun, 19 Jun 2022 10:02:51 -0700
Subject: [PATCH] Include bsd/strings.h if it exists

Some systems apparently put strlcpy() into a separate bsd/strings.h file
without putting the function into a separate library. Thus, configure
finds that the function exists for linking but the build does not have
the declaration (which rsync only supplies if it is also supplying its
own version of the function).
---
 configure.ac | 3 ++-
 rsync.h      | 3 +++
 2 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/configure.ac b/configure.ac
index 37dbb18a..37241637 100644
--- a/configure.ac
+++ b/configure.ac
@@ -13,7 +13,8 @@ AC_CHECK_HEADERS(sys/fcntl.h sys/select.h fcntl.h sys/time.h sys/unistd.h \
     netdb.h malloc.h float.h limits.h iconv.h libcharset.h langinfo.h mcheck.h \
     sys/acl.h acl/libacl.h attr/xattr.h sys/xattr.h sys/extattr.h dl.h \
     popt.h popt/popt.h linux/falloc.h netinet/in_systm.h netgroup.h \
-    zlib.h xxhash.h openssl/md4.h openssl/md5.h zstd.h lz4.h sys/file.h)
+    zlib.h xxhash.h openssl/md4.h openssl/md5.h zstd.h lz4.h sys/file.h \
+    bsd/string.h)
 AC_CHECK_HEADERS([netinet/ip.h], [], [], [[#include <netinet/in.h>]])
 AC_HEADER_MAJOR_FIXED
 
diff --git a/rsync.h b/rsync.h
index e5aacd25..1cc037c5 100644
--- a/rsync.h
+++ b/rsync.h
@@ -338,6 +338,9 @@ enum delret {
 # endif
 # include <string.h>
 #endif
+#ifdef HAVE_BSD_STRING_H
+# include <bsd/string.h>
+#endif
 #ifdef HAVE_STRINGS_H
 # include <strings.h>
 #endif