TF-RMM Release v0.1.0
This is the first external release of TF-RMM and provides a reference
implementation of Realm Management Monitor (RMM) as specified by the
RMM Beta0 specification[1].
The `docs/readme.rst` has more details about the project and
`docs/getting_started/getting-started.rst` has details on how to get
started with TF-RMM.
[1] https://developer.arm.com/documentation/den0137/1-0bet0/?lang=en
Signed-off-by: Soby Mathew <soby.mathew@arm.com>
Change-Id: I205ef14c015e4a37ae9ae1a64e4cd22eb8da746e
diff --git a/lib/libc/src/memmove.c b/lib/libc/src/memmove.c
new file mode 100644
index 0000000..b8acb65
--- /dev/null
+++ b/lib/libc/src/memmove.c
@@ -0,0 +1,34 @@
+/*
+ * SPDX-License-Identifier: BSD-3-Clause
+ * SPDX-FileCopyrightText: Copyright TF-RMM Contributors.
+ * SPDX-FileCopyrightText: Copyright Jon Medhurst <tixy@linaro.org>
+ */
+
+#include <stddef.h>
+#include <string.h>
+
+void *memmove(void *dst, const void *src, size_t len)
+{
+ /*
+ * The following test makes use of unsigned arithmetic overflow to
+ * more efficiently test the condition !(src <= dst && dst < str+len).
+ * It also avoids the situation where the more explicit test would give
+ * incorrect results were the calculation str+len to overflow (though
+ * that issue is probably moot as such usage is probably undefined
+ * behaviour and a bug anyway.
+ */
+ if ((size_t)dst - (size_t)src >= len) {
+ /* destination not in source data, so can safely use memcpy */
+ return memcpy(dst, src, len);
+ }
+
+ /* copy backwards... */
+ const char *end = dst;
+ const char *s = (const char *)src + len;
+ char *d = (char *)dst + len;
+
+ while (d != end) {
+ *--d = *--s;
+ }
+ return dst;
+}