Colony » Colony Scout

/*-

 * Copyright (c) 1990, 1993

 *        The Regents of the University of California.  All rights reserved.

 *

 * This code is derived from software contributed to Berkeley by

 * Chris Torek.

 *

 * Redistribution and use in source and binary forms, with or without

 * modification, are permitted provided that the following conditions

 * are met:

 * 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. 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

 * SUCH DAMAGE.

 */

#include <sys/cdefs.h>

#include <string.h>

/*

 * Copy a block of memory, handling overlap.

 * This is the routine that actually implements

 * (the portable versions of) bcopy, memcpy, and memmove.

 */

#ifdef MEMCOPY

void *

memcpy(dst0, src0, length)

#else

#ifdef MEMMOVE

void *

memmove(dst0, src0, length)

#else

void

bcopy(src0, dst0, length)

#endif

#endif

        void *dst0;

        const void *src0;

        size_t length;

{

        char *dst = dst0;

        const char *src = src0;

        if (length == 0 || dst == src)                /* nothing to do */

                goto done;

        if (((unsigned long)dst < (unsigned long)src) &&

            ((unsigned long)dst < (unsigned long)src + length)) {

                /* Copy backwards. */

                src += length;

                dst += length;

                while (length--) {

                        *--dst = *--src;

                }

        } else {

                while (length--) {

                        *dst++ = *src++;

                }

        }

done:

#if defined(MEMCOPY) || defined(MEMMOVE)

        return (dst0);

#else

        return;

#endif

}