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-rw-r--r--lib/memmove.c49
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+/**
+** @file memmove.c
+**
+** @author Numerous CSCI-452 classes
+**
+** @brief C implementations of common library functions
+*/
+
+#ifndef MEMMOVE_SRC_INC
+#define MEMMOVE_SRC_INC
+
+#include <common.h>
+
+#include <lib.h>
+
+/**
+** memmove(dst,src,len)
+**
+** Copy a block from one place to another. Deals with overlapping
+** buffers.
+**
+** @param dst Destination buffer
+** @param src Source buffer
+** @param len Buffer size (in bytes)
+*/
+void memmove(void *dst, const void *src, register uint32_t len)
+{
+ register uint8_t *dest = dst;
+ register const uint8_t *source = src;
+
+ /*
+ ** We could speed this up by unrolling it and copying
+ ** words at a time (instead of bytes).
+ */
+
+ if (source < dest && (source + len) > dest) {
+ source += len;
+ dest += len;
+ while (len-- > 0) {
+ *--dest = *--source;
+ }
+ } else {
+ while (len--) {
+ *dest++ = *source++;
+ }
+ }
+}
+
+#endif