lib/: Move memzero.[ch] under lib/string/memset/

Signed-off-by: Alejandro Colomar <alx@kernel.org>

lib/string/memset/memzero.c

@@ -0,0 +1,15 @@
+// SPDX-FileCopyrightText: 2023, Alejandro Colomar <alx@kernel.org>
+// SPDX-License-Identifier: BSD-3-Clause
+
+
+#include <config.h>
+
+#ident "$Id$"
+
+#include <stddef.h>
+
+#include "string/memset/memzero.h"
+
+
+extern inline void memzero(void *ptr, size_t size);
+extern inline void strzero(char *s);

lib/string/memset/memzero.h

@@ -0,0 +1,47 @@
+// SPDX-FileCopyrightText: 2022-2023, Christian Göttsche <cgzones@googlemail.com>
+// SPDX-FileCopyrightText: 2023, Alejandro Colomar <alx@kernel.org>
+// SPDX-License-Identifier: BSD-3-Clause
+
+
+#ifndef SHADOW_INCLUDE_LIB_STRING_MEMSET_MEMZERO_H_
+#define SHADOW_INCLUDE_LIB_STRING_MEMSET_MEMZERO_H_
+
+
+#include <config.h>
+
+#include <stddef.h>
+#include <string.h>
+#include <strings.h>
+
+#include "sizeof.h"
+
+
+#define MEMZERO(arr)  memzero(arr, SIZEOF_ARRAY(arr))
+
+
+inline void memzero(void *ptr, size_t size);
+inline void strzero(char *s);
+
+
+inline void
+memzero(void *ptr, size_t size)
+{
+#if defined(HAVE_MEMSET_EXPLICIT)
+	memset_explicit(ptr, 0, size);
+#elif defined(HAVE_EXPLICIT_BZERO)
+	explicit_bzero(ptr, size);
+#else
+	bzero(ptr, size);
+	__asm__ __volatile__ ("" : : "r"(ptr) : "memory");
+#endif
+}
+
+
+inline void
+strzero(char *s)
+{
+	memzero(s, strlen(s));
+}
+
+
+#endif  // include guard