[PATCH v1] explicit_bzero.c: using explicit_memset on NetBSD

From 20d36249e791ac8a7f31725e3e2b54ec5270ac73 Mon Sep 17 00:00:00 2001
From: David Carlier <devnexen@gmail.com>
Date: Sun, 30 Aug 2020 12:57:58 +0000
Subject: [PATCH] explicit_bzero.c: uses explicit_memset for NetBSD.

It provides the same guarantee as explicit_bzero to avoid compiler optimisation.

Signed-off-by: David Carlier <devnexen@gmail.com>
---
 configure                  | 13 +++++++++++++
 configure.ac               |  1 +
 src/include/pg_config.h.in |  3 +++
 src/port/explicit_bzero.c  |  8 ++++++++
 4 files changed, 25 insertions(+)

diff --git a/configure b/configure
index cb8fbe1051..c3da20c050 100755
--- a/configure
+++ b/configure
@@ -15735,6 +15735,19 @@ esac
 
 fi
 
+ac_fn_c_check_func "$LINENO" "explicit_memset" "ac_cv_func_explicit_memset"
+if test "x$ac_cv_func_explicit_memset" = xyes; then :
+  $as_echo "#define HAVE_EXPLICIT_MEMSET 1" >>confdefs.h
+
+else
+  case " $LIBOBJS " in
+  *" explicit_memset.$ac_objext "* ) ;;
+  *) LIBOBJS="$LIBOBJS explicit_memset.$ac_objext"
+ ;;
+esac
+
+fi
+
 ac_fn_c_check_func "$LINENO" "fls" "ac_cv_func_fls"
 if test "x$ac_cv_func_fls" = xyes; then :
   $as_echo "#define HAVE_FLS 1" >>confdefs.h
diff --git a/configure.ac b/configure.ac
index eb2c731b58..38e59a7eee 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1721,6 +1721,7 @@ fi
 AC_REPLACE_FUNCS(m4_normalize([
 	dlopen
 	explicit_bzero
+	explicit_memset
 	fls
 	getopt
 	getpeereid
diff --git a/src/include/pg_config.h.in b/src/include/pg_config.h.in
index fb270df678..07ad2bcff5 100644
--- a/src/include/pg_config.h.in
+++ b/src/include/pg_config.h.in
@@ -185,6 +185,9 @@
 /* Define to 1 if you have the `explicit_bzero' function. */
 #undef HAVE_EXPLICIT_BZERO
 
+/* Define to 1 if you have the `explicit_memset' function. */
+#undef HAVE_EXPLICIT_MEMSET
+
 /* Define to 1 if you have the `fdatasync' function. */
 #undef HAVE_FDATASYNC
 
diff --git a/src/port/explicit_bzero.c b/src/port/explicit_bzero.c
index 6bd8b0dd9d..214ba4aa26 100644
--- a/src/port/explicit_bzero.c
+++ b/src/port/explicit_bzero.c
@@ -22,6 +22,14 @@ explicit_bzero(void *buf, size_t len)
 	(void) memset_s(buf, len, 0, len);
 }
 
+#elif defined(HAVE_EXPLICIT_MEMSET)
+
+void
+explicit_bzero(void *buf, size_t len)
+{
+	(void) explicit_memset(buf, 0, len);
+}
+
 #elif defined(WIN32)
 
 void
-- 
2.27.0