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--- Libc/Libc-825.24/string/FreeBSD/bcopy.c
+++ Libc/Libc-320/string/FreeBSD/bcopy.c
@@ -13,6 +13,10 @@
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
+ * 3. All advertising materials mentioning features or use of this software
+ * must display the following acknowledgement:
+ * This product includes software developed by the University of
+ * California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
@@ -30,3 +34,106 @@
* SUCH DAMAGE.
*/
+#if defined(LIBC_SCCS) && !defined(lint)
+static char sccsid[] = "@(#)bcopy.c 8.1 (Berkeley) 6/4/93";
+#endif /* LIBC_SCCS and not lint */
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD: src/lib/libc/string/bcopy.c,v 1.5 2002/09/01 21:53:46 robert Exp $");
+
+/*
+ * sizeof(word) MUST BE A POWER OF TWO
+ * SO THAT wmask BELOW IS ALL ONES
+ */
+typedef int word; /* "word" used for optimal copy speed */
+
+#define wsize sizeof(word)
+#define wmask (wsize - 1)
+
+/*
+ * Copy a block of memory, handling overlap.
+ * This is the routine that actually implements
+ * (the portable versions of) bcopy, memcpy, and memmove.
+ */
+#if defined(MEMCOPY) || defined(MEMMOVE)
+#include <string.h>
+
+void *
+#ifdef MEMCOPY
+memcpy
+#else
+memmove
+#endif
+(void *dst0, const void *src0, size_t length)
+#else
+#include <strings.h>
+
+void
+bcopy(const void *src0, void *dst0, size_t length)
+#endif
+{
+ char *dst = dst0;
+ const char *src = src0;
+ size_t t;
+
+ if (length == 0 || dst == src) /* nothing to do */
+ goto done;
+
+ /*
+ * Macros: loop-t-times; and loop-t-times, t>0
+ */
+#define TLOOP(s) if (t) TLOOP1(s)
+#define TLOOP1(s) do { s; } while (--t)
+
+ if ((unsigned long)dst < (unsigned long)src) {
+ /*
+ * Copy forward.
+ */
+ t = (int)src; /* only need low bits */
+ if ((t | (int)dst) & wmask) {
+ /*
+ * Try to align operands. This cannot be done
+ * unless the low bits match.
+ */
+ if ((t ^ (int)dst) & wmask || length < wsize)
+ t = length;
+ else
+ t = wsize - (t & wmask);
+ length -= t;
+ TLOOP1(*dst++ = *src++);
+ }
+ /*
+ * Copy whole words, then mop up any trailing bytes.
+ */
+ t = length / wsize;
+ TLOOP(*(word *)dst = *(word *)src; src += wsize; dst += wsize);
+ t = length & wmask;
+ TLOOP(*dst++ = *src++);
+ } else {
+ /*
+ * Copy backwards. Otherwise essentially the same.
+ * Alignment works as before, except that it takes
+ * (t&wmask) bytes to align, not wsize-(t&wmask).
+ */
+ src += length;
+ dst += length;
+ t = (int)src;
+ if ((t | (int)dst) & wmask) {
+ if ((t ^ (int)dst) & wmask || length <= wsize)
+ t = length;
+ else
+ t &= wmask;
+ length -= t;
+ TLOOP1(*--dst = *--src);
+ }
+ t = length / wsize;
+ TLOOP(src -= wsize; dst -= wsize; *(word *)dst = *(word *)src);
+ t = length & wmask;
+ TLOOP(*--dst = *--src);
+ }
+done:
+#if defined(MEMCOPY) || defined(MEMMOVE)
+ return (dst0);
+#else
+ return;
+#endif
+}