bootx.tproj/libclite.subproj/mem.c

   1 /*
   2  * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * The contents of this file constitute Original Code as defined in and
   7  * are subject to the Apple Public Source License Version 1.1 (the
   8  * "License").  You may not use this file except in compliance with the
   9  * License.  Please obtain a copy of the License at
  10  * http://www.apple.com/publicsource and read it before using this file.
  11  *
  12  * This Original Code and all software distributed under the License are
  13  * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  14  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  15  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  16  * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
  17  * License for the specific language governing rights and limitations
  18  * under the License.
  19  *
  20  * @APPLE_LICENSE_HEADER_END@
  21  */
  22 /*
  23  *  mem.c - Standard memory functions.
  24  *
  25  *  Copyright (c) 1998-2000 Apple Computer, Inc.
  26  *
  27  *  DRI: Josh de Cesare
  28  */
  29
  30 #import <libclite.h>
  31 #import <ci.h>
  32
  33
  34 void *memcpy(void *dst, const void *src, size_t len)
  35 {
  36   char *s = src, *d = dst;
  37   int pos = 0, dir = 1;
  38
  39   if (d > s) {
  40     dir = -1;
  41     pos = len - 1;
  42   }
  43
  44   while (len--) {
  45     d[pos] = s[pos];
  46     pos += dir;
  47   }
  48
  49   return dst;
  50 }
  51
  52
  53 void *memset(void *dst, int ch, size_t len)
  54 {
  55   long tmp = 0x01010101 * (ch & 0x000000FF);
  56
  57   if (len < 32) while (len--) *(((char *)dst)++) = ch;
  58   else {
  59     // do the front chunk as chars
  60     while ((long)dst & 3) {
  61       len--;
  62       *(((char *)dst)++) = ch;
  63     }
  64
  65     // do the middle chunk as longs
  66     while (len > 3) {
  67       len -= 4;
  68       *(((long *)dst)++) = tmp;
  69     }
  70
  71     // do the last chunk as chars
  72     while (len--) *(((char *)dst)++) = ch;
  73   }
  74
  75   return dst;
  76 }
  77
  78 void *bcopy(void *src, void *dst, int len)
  79 {
  80   return memcpy(dst, src, len);
  81 }
  82
  83 void bzero(void *dst, int len)
  84 {
  85   memset(dst, 0, len);
  86 }
  87