qemu/roms/SLOF/lib/libc/string/memmove.c

   1 /******************************************************************************
   2  * Copyright (c) 2004, 2008 IBM Corporation
   3  * All rights reserved.
   4  * This program and the accompanying materials
   5  * are made available under the terms of the BSD License
   6  * which accompanies this distribution, and is available at
   7  * http://www.opensource.org/licenses/bsd-license.php
   8  *
   9  * Contributors:
  10  *     IBM Corporation - initial implementation
  11  *****************************************************************************/
  12
  13 #include "string.h"
  14
  15
  16 void *
  17 memmove(void *dest, const void *src, size_t n)
  18 {
  19         char *cdest;
  20         const char *csrc;
  21         int i;
  22
  23         /* Do the buffers overlap in a bad way? */
  24         if (src < dest && src + n >= dest) {
  25                 /* Copy from end to start */
  26                 cdest = dest + n - 1;
  27                 csrc = src + n - 1;
  28                 for (i = 0; i < n; i++) {
  29                         *cdest-- = *csrc--;
  30                 }
  31         }
  32         else {
  33                 /* Normal copy is possible */
  34                 cdest = dest;
  35                 csrc = src;
  36                 for (i = 0; i < n; i++) {
  37                         *cdest++ = *csrc++;
  38                 }
  39         }
  40
  41         return dest;
  42 }