1*479ab7f0SSascha Wildner /*-
2*479ab7f0SSascha Wildner * Copyright (c) 1998 Michael Smith
3*479ab7f0SSascha Wildner * All rights reserved.
4*479ab7f0SSascha Wildner *
5*479ab7f0SSascha Wildner * Redistribution and use in source and binary forms, with or without
6*479ab7f0SSascha Wildner * modification, are permitted provided that the following conditions
7*479ab7f0SSascha Wildner * are met:
8*479ab7f0SSascha Wildner * 1. Redistributions of source code must retain the above copyright
9*479ab7f0SSascha Wildner * notice, this list of conditions and the following disclaimer.
10*479ab7f0SSascha Wildner * 2. Redistributions in binary form must reproduce the above copyright
11*479ab7f0SSascha Wildner * notice, this list of conditions and the following disclaimer in the
12*479ab7f0SSascha Wildner * documentation and/or other materials provided with the distribution.
13*479ab7f0SSascha Wildner *
14*479ab7f0SSascha Wildner * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15*479ab7f0SSascha Wildner * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16*479ab7f0SSascha Wildner * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17*479ab7f0SSascha Wildner * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18*479ab7f0SSascha Wildner * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19*479ab7f0SSascha Wildner * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20*479ab7f0SSascha Wildner * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21*479ab7f0SSascha Wildner * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22*479ab7f0SSascha Wildner * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23*479ab7f0SSascha Wildner * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24*479ab7f0SSascha Wildner * SUCH DAMAGE.
25*479ab7f0SSascha Wildner *
26*479ab7f0SSascha Wildner * $FreeBSD: src/lib/libstand/sbrk.c,v 1.2.2.1 2000/05/18 08:00:57 ps Exp $
27*479ab7f0SSascha Wildner */
28*479ab7f0SSascha Wildner
29*479ab7f0SSascha Wildner /*
30*479ab7f0SSascha Wildner * Minimal sbrk() emulation required for malloc support.
31*479ab7f0SSascha Wildner */
32*479ab7f0SSascha Wildner
33*479ab7f0SSascha Wildner #include <string.h>
34*479ab7f0SSascha Wildner #include "stand.h"
35*479ab7f0SSascha Wildner
36*479ab7f0SSascha Wildner static size_t maxheap, heapsize = 0;
37*479ab7f0SSascha Wildner static void *sbrkbase;
38*479ab7f0SSascha Wildner
39*479ab7f0SSascha Wildner void
setheap(void * base,void * top)40*479ab7f0SSascha Wildner setheap(void *base, void *top)
41*479ab7f0SSascha Wildner {
42*479ab7f0SSascha Wildner /* Align start address to 16 bytes for the malloc code. Sigh. */
43*479ab7f0SSascha Wildner sbrkbase = (void *)(((uintptr_t)base + 15) & ~15);
44*479ab7f0SSascha Wildner maxheap = top - sbrkbase;
45*479ab7f0SSascha Wildner }
46*479ab7f0SSascha Wildner
47*479ab7f0SSascha Wildner char *
getheap(size_t * sizep)48*479ab7f0SSascha Wildner getheap(size_t *sizep)
49*479ab7f0SSascha Wildner {
50*479ab7f0SSascha Wildner *sizep = maxheap;
51*479ab7f0SSascha Wildner return sbrkbase;
52*479ab7f0SSascha Wildner }
53*479ab7f0SSascha Wildner
54*479ab7f0SSascha Wildner char *
sbrk(intptr_t incr)55*479ab7f0SSascha Wildner sbrk(intptr_t incr)
56*479ab7f0SSascha Wildner {
57*479ab7f0SSascha Wildner char *ret;
58*479ab7f0SSascha Wildner
59*479ab7f0SSascha Wildner if ((heapsize + incr) <= maxheap) {
60*479ab7f0SSascha Wildner ret = sbrkbase + heapsize;
61*479ab7f0SSascha Wildner bzero(ret, incr);
62*479ab7f0SSascha Wildner heapsize += incr;
63*479ab7f0SSascha Wildner return(ret);
64*479ab7f0SSascha Wildner }
65*479ab7f0SSascha Wildner errno = ENOMEM;
66*479ab7f0SSascha Wildner return((char *)-1);
67*479ab7f0SSascha Wildner }
68