NetBSD/common/lib/libc/string/memset.c
tsutsui d0b9e6c924 - remove bcmp(9), bcopy(9), and bzero(9) from libkern since <sys/systm.h> has
macro which replace them with mem*() functions in #ifdef _KERNEL as noted
  in man pages
- move declarations of bcopy(3) and bzero(3) into <lib/libsa/stand.h>
  since they are still in libsa for some MD standalone sources
  (I guess all bcmp(3) in standalone sources have been replaced with memcmp(3)
   but they should be replaced with memcmp() anyway)
2009-03-18 12:25:06 +00:00

168 lines
4.3 KiB
C

/* $NetBSD: memset.c,v 1.8 2009/03/18 12:25:06 tsutsui Exp $ */
/*-
* Copyright (c) 1990, 1993
* The Regents of the University of California. All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Mike Hibler and 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>
#if defined(LIBC_SCCS) && !defined(lint)
#if 0
static char sccsid[] = "@(#)memset.c 8.1 (Berkeley) 6/4/93";
#else
__RCSID("$NetBSD: memset.c,v 1.8 2009/03/18 12:25:06 tsutsui Exp $");
#endif
#endif /* LIBC_SCCS and not lint */
#include <sys/types.h>
#if !defined(_KERNEL) && !defined(_STANDALONE)
#include <assert.h>
#include <limits.h>
#include <string.h>
#else
#include <lib/libkern/libkern.h>
#if defined(BZERO) && defined(_STANDALONE)
#include <lib/libsa/stand.h>
#endif
#include <machine/limits.h>
#endif
#define wsize sizeof(u_int)
#define wmask (wsize - 1)
#ifdef _FORTIFY_SOURCE
#undef bzero
#undef memset
#endif
#ifndef __OPTIMIZE_SIZE__
#ifdef BZERO
#define RETURN return
#define VAL 0
#define WIDEVAL 0
void
bzero(void *dst0, size_t length)
#else
#define RETURN return (dst0)
#define VAL c0
#define WIDEVAL c
void *
memset(void *dst0, int c0, size_t length)
#endif
{
size_t t;
#ifndef BZERO
u_int c;
#endif
u_char *dst;
_DIAGASSERT(dst0 != 0);
dst = dst0;
/*
* If not enough words, just fill bytes. A length >= 2 words
* guarantees that at least one of them is `complete' after
* any necessary alignment. For instance:
*
* |-----------|-----------|-----------|
* |00|01|02|03|04|05|06|07|08|09|0A|00|
* ^---------------------^
* dst dst+length-1
*
* but we use a minimum of 3 here since the overhead of the code
* to do word writes is substantial.
*/
if (length < 3 * wsize) {
while (length != 0) {
*dst++ = VAL;
--length;
}
RETURN;
}
#ifndef BZERO
if ((c = (u_char)c0) != 0) { /* Fill the word. */
c = (c << 8) | c; /* u_int is 16 bits. */
#if UINT_MAX > 0xffff
c = (c << 16) | c; /* u_int is 32 bits. */
#endif
#if UINT_MAX > 0xffffffff
c = (c << 32) | c; /* u_int is 64 bits. */
#endif
}
#endif
/* Align destination by filling in bytes. */
if ((t = (size_t)((u_long)dst & wmask)) != 0) {
t = wsize - t;
length -= t;
do {
*dst++ = VAL;
} while (--t != 0);
}
/* Fill words. Length was >= 2*words so we know t >= 1 here. */
t = length / wsize;
do {
*(u_int *)(void *)dst = WIDEVAL;
dst += wsize;
} while (--t != 0);
/* Mop up trailing bytes, if any. */
t = length & wmask;
if (t != 0)
do {
*dst++ = VAL;
} while (--t != 0);
RETURN;
}
#else /* __OPTIMIZE_SIZE__ */
#ifdef BZERO
void
bzero(void *dstv, size_t length)
{
u_char *dst = dstv;
while (length-- > 0)
*dst++ = 0;
}
#else
void *
memset(void *dstv, int c, size_t length)
{
u_char *dst = dstv;
while (length-- > 0)
*dst++ = c;
return dstv;
}
#endif /* BZERO */
#endif /* __OPTIMIZE_SIZE__ */