memset.c

来自「freescale的bdm调试工具软件.包括原理图,和cpld源代码.」· C语言 代码 · 共 54 行

/*
 * memset.c - replacement for memset(3), using duff's device.
 * Copyright (C) 1995 - 2004 Michael Riepe
 * 
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Library General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 * 
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Library General Public License for more details.
 * 
 * You should have received a copy of the GNU Library General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

#if HAVE_CONFIG_H
# include <config.h>
#endif /* HAVE_CONFIG_H */

#ifndef lint
static const char rcsid[] = "@(#) $Id: memset.c,v 1.1 2008/06/16 00:01:22 cjohns Exp $";
#endif /* lint */

#include <stddef.h>	/* for size_t */
#include <sys/types.h>

void*
_elf_memset(void *s, int c, size_t n) {
    char *t = (char*)s;

    if (n) {
	switch (n % 8u) {
	    do {
		n -= 8;
		default:
		case 0: *t++ = (char)c;
		case 7: *t++ = (char)c;
		case 6: *t++ = (char)c;
		case 5: *t++ = (char)c;
		case 4: *t++ = (char)c;
		case 3: *t++ = (char)c;
		case 2: *t++ = (char)c;
		case 1: *t++ = (char)c;
	    }
	    while (n > 8);
	}
    }
    return s;
}