Add build system scaffolding and libc headers

1 files changed, 21 insertions, 0 deletions

diff --git a/lib/libc/string/memmove.c b/lib/libc/string/memmove.c
new file mode 100644
index 00000000..88968185
--- /dev/null
+++ b/lib/libc/string/memmove.c
@@ -0,0 +1,21 @@
+#include <stddef.h>
+#include <stdint.h>
+
+void *memmove(void *dst, const void *src, size_t n)
+{
+	uint8_t *d = dst;
+	const uint8_t *s = src;
+
+	if (d == s || n == 0)
+		return dst;
+
+	if ((uintptr_t)d < (uintptr_t)s) {
+		for (size_t i = 0; i < n; i++)
+			d[i] = s[i];
+	} else {
+		for (size_t i = n; i != 0; i--)
+			d[i - 1] = s[i - 1];
+	}
+
+	return dst;
+}