Changes in kernel/generic/src/lib/mem.c [b169619:174156fd] in mainline

File:

• kernel/generic/src/lib/mem.c (modified) (2 diffs)

kernel/generic/src/lib/mem.c

@@ -41 +41 @@
  */
 
-#include <memw.h>
+#include <mem.h>
 #include <typedefs.h>
 
@@ -77 +77 @@
 }
 
+/** Move memory block with possible overlapping.
+ *
+ * Copy cnt bytes from src address to dst address. The source
+ * and destination memory areas may overlap.
+ *
+ * @param dst Destination address to copy to.
+ * @param src Source address to copy from.
+ * @param cnt Number of bytes to copy.
+ *
+ * @return Destination address.
+ *
+ */
+void *memmove(void *dst, const void *src, size_t cnt)
+{
+        /* Nothing to do? */
+        if (src == dst)
+                return dst;
+
+        /* Non-overlapping? */
+        if ((dst >= src + cnt) || (src >= dst + cnt))
+                return memcpy(dst, src, cnt);
+
+        uint8_t *dp;
+        const uint8_t *sp;
+
+        /* Which direction? */
+        if (src > dst) {
+                /* Forwards. */
+                dp = dst;
+                sp = src;
+
+                while (cnt-- != 0)
+                        *dp++ = *sp++;
+        } else {
+                /* Backwards. */
+                dp = dst + (cnt - 1);
+                sp = src + (cnt - 1);
+
+                while (cnt-- != 0)
+                        *dp-- = *sp--;
+        }
+
+        return dst;
+}
+
 /** @}
  */