99 lines
3.0 KiB
C
99 lines
3.0 KiB
C
/* $NetBSD: mem2.c,v 1.3 1995/10/02 17:27:11 jpo Exp $ */
|
|
|
|
/*
|
|
* Copyright (c) 1994, 1995 Jochen Pohl
|
|
* All Rights Reserved.
|
|
*
|
|
* 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. All advertising materials mentioning features or use of this software
|
|
* must display the following acknowledgement:
|
|
* This product includes software developed by Jochen Pohl for
|
|
* The NetBSD Project.
|
|
* 4. The name of the author may not be used to endorse or promote products
|
|
* derived from this software without specific prior written permission.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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.
|
|
*/
|
|
|
|
#ifndef lint
|
|
static const char rcsid[] =
|
|
"$FreeBSD$";
|
|
#endif
|
|
|
|
#include <sys/param.h>
|
|
#include <sys/types.h>
|
|
#include <sys/mman.h>
|
|
#include <unistd.h>
|
|
#include <string.h>
|
|
#include <err.h>
|
|
|
|
#include "lint2.h"
|
|
|
|
/* length of new allocated memory blocks */
|
|
static size_t mblklen;
|
|
|
|
/* offset of next free byte in mbuf */
|
|
static size_t nxtfree;
|
|
|
|
/* current buffer to server memory requests from */
|
|
static void *mbuf;
|
|
|
|
void
|
|
initmem()
|
|
{
|
|
int pgsz;
|
|
|
|
pgsz = getpagesize();
|
|
mblklen = ((MBLKSIZ + pgsz - 1) / pgsz) * pgsz;
|
|
|
|
nxtfree = mblklen;
|
|
}
|
|
|
|
/*
|
|
* Allocate memory in large chunks to avoid space and time overhead of
|
|
* malloc(). This is possible because memory allocated by xalloc()
|
|
* need never to be freed.
|
|
*/
|
|
void *
|
|
xalloc(sz)
|
|
size_t sz;
|
|
{
|
|
void *ptr;
|
|
int prot, flags;
|
|
|
|
sz = ALIGN(sz);
|
|
if (nxtfree + sz > mblklen) {
|
|
/* use mmap() instead of malloc() to avoid malloc overhead. */
|
|
prot = PROT_READ | PROT_WRITE;
|
|
flags = MAP_ANON | MAP_PRIVATE;
|
|
mbuf = mmap(NULL, mblklen, prot, flags, -1, (off_t)0);
|
|
if (mbuf == (void *)MAP_FAILED)
|
|
err(1, "can't map memory");
|
|
if (ALIGN((u_long)mbuf) != (u_long)mbuf)
|
|
errx(1, "mapped address is not aligned");
|
|
(void)memset(mbuf, 0, mblklen);
|
|
nxtfree = 0;
|
|
}
|
|
|
|
ptr = (char *)mbuf + nxtfree;
|
|
nxtfree += sz;
|
|
|
|
return (ptr);
|
|
}
|