1 /* $NetBSD: mem2.c,v 1.3 1995/10/02 17:27:11 jpo Exp $ */
4 * Copyright (c) 1994, 1995 Jochen Pohl
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 * 3. All advertising materials mentioning features or use of this software
16 * must display the following acknowledgement:
17 * This product includes software developed by Jochen Pohl for
19 * 4. The name of the author may not be used to endorse or promote products
20 * derived from this software without specific prior written permission.
22 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
23 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
24 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
25 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
26 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
27 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
28 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
29 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
30 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
31 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
33 * $DragonFly: src/usr.bin/xlint/lint2/mem2.c,v 1.3 2004/07/07 12:13:26 asmodai Exp $
36 #include <sys/param.h>
37 #include <sys/types.h>
45 /* length of new allocated memory blocks */
46 static size_t mblklen
;
48 /* offset of next free byte in mbuf */
49 static size_t nxtfree
;
51 /* current buffer to server memory requests from */
60 mblklen
= ((MBLKSIZ
+ pgsz
- 1) / pgsz
) * pgsz
;
66 * Allocate memory in large chunks to avoid space and time overhead of
67 * malloc(). This is possible because memory allocated by xalloc()
68 * need never to be freed.
77 if (nxtfree
+ sz
> mblklen
) {
78 /* use mmap() instead of malloc() to avoid malloc overhead. */
79 prot
= PROT_READ
| PROT_WRITE
;
80 flags
= MAP_ANON
| MAP_PRIVATE
;
81 mbuf
= mmap(NULL
, mblklen
, prot
, flags
, -1, (off_t
)0);
82 if (mbuf
== (void *)MAP_FAILED
)
83 err(1, "can't map memory");
84 if (ALIGN((u_long
)mbuf
) != (u_long
)mbuf
)
85 errx(1, "mapped address is not aligned");
86 (void)memset(mbuf
, 0, mblklen
);
90 ptr
= (char *)mbuf
+ nxtfree
;