1 /* 2 * Copyright (c) 1987 Regents of the University of California. 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms are permitted 6 * provided that the above copyright notice and this paragraph are 7 * duplicated in all such forms and that any documentation, 8 * advertising materials, and other materials related to such 9 * distribution and use acknowledge that the software was developed 10 * by the University of California, Berkeley. The name of the 11 * University may not be used to endorse or promote products derived 12 * from this software without specific prior written permission. 13 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR 14 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED 15 * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE. 16 */ 17 18 #if defined(LIBC_SCCS) && !defined(lint) 19 static char sccsid[] = "@(#)bcopy.c 5.2 (Berkeley) 07/21/88"; 20 #endif /* LIBC_SCCS and not lint */ 21 22 /* 23 * bcopy -- vax movc3 instruction 24 */ 25 bcopy(src, dst, length) 26 register char *src, *dst; 27 register int length; 28 { 29 if (length && src != dst) 30 if ((u_int)dst < (u_int)src) 31 if (((int)src | (int)dst | length) & 3) 32 do /* copy by bytes */ 33 *dst++ = *src++; 34 while (--length); 35 else { 36 length >>= 2; 37 do /* copy by longs */ 38 *((long *)dst)++ = *((long *)src)++; 39 while (--length); 40 } 41 else { /* copy backwards */ 42 src += length; 43 dst += length; 44 if (((int)src | (int)dst | length) & 3) 45 do /* copy by bytes */ 46 *--dst = *--src; 47 while (--length); 48 else { 49 length >>= 2; 50 do /* copy by shorts */ 51 *--((long *)dst) = *--((long *)src); 52 while (--length); 53 } 54 } 55 return(0); 56 } 57