* Copyright (c) 1990, 1993
* The Regents of the University of California. All rights reserved.
* This code is derived from software contributed to Berkeley by
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 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.
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
#if defined(LIBC_SCCS) && !defined(lint)
static char sccsid
[] = "@(#)bcopy.c 8.1 (Berkeley) 6/4/93";
#endif /* LIBC_SCCS and not lint */
* 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.
memcpy(dst0
, src0
, length
)
memmove(dst0
, src0
, length
)
bcopy(src0
, dst0
, length
)
register char *dst
= dst0
;
register const char *src
= src0
;
if (length
== 0 || dst
== src
) /* nothing to do */
* 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
) {
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
)
* Copy whole words, then mop up any trailing bytes.
TLOOP(*(word
*)dst
= *(word
*)src
; src
+= wsize
; dst
+= wsize
);
* Copy backwards. Otherwise essentially the same.
* Alignment works as before, except that it takes
* (t&wmask) bytes to align, not wsize-(t&wmask).
if ((t
| (int)dst
) & wmask
) {
if ((t
^ (int)dst
) & wmask
|| length
<= wsize
)
TLOOP(src
-= wsize
; dst
-= wsize
; *(word
*)dst
= *(word
*)src
);
#if defined(MEMCOPY) || defined(MEMMOVE)