1 files changed, 42 insertions, 0 deletions
diff --git a/libc/string/memmove.c b/libc/string/memmove.c
new file mode 100644
index 00000000..3acf1a97
--- /dev/null
+++ b/libc/string/memmove.c
@@ -0,0 +1,42 @@
+/******************************************************************************
+ * Copyright (c) 2004, 2008 IBM Corporation
+ * All rights reserved.
+ * This program and the accompanying materials
+ * are made available under the terms of the BSD License
+ * which accompanies this distribution, and is available at
+ * http://www.opensource.org/licenses/bsd-license.php
+ *
+ * Contributors:
+ *     IBM Corporation - initial implementation
+ *****************************************************************************/
+
+#include "string.h"
+
+
+void *
+memmove(void *dest, const void *src, size_t n)
+{
+	char *cdest;
+	const char *csrc;
+	int i;
+
+	/* Do the buffers overlap in a bad way? */
+	if (src < dest && src + n >= dest) {
+		/* Copy from end to start */
+		cdest = dest + n - 1;
+		csrc = src + n - 1;
+		for (i = 0; i < n; i++) {
+			*cdest-- = *csrc--;
+		}
+	}
+	else {
+		/* Normal copy is possible */
+		cdest = dest;
+		csrc = src;
+		for (i = 0; i < n; i++) {
+			*cdest++ = *csrc++;
+		}
+	}
+
+	return dest;
+}