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/*-
* Copyright (c) 1998 Michael Smith
* 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.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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>
__FBSDID("$FreeBSD$");
/*
* Minimal sbrk() emulation required for malloc support.
*/
#include <string.h>
#include "stand.h"
#include "zalloc_defs.h"
static size_t maxheap, heapsize = 0;
static void *heapbase;
void
setheap(void *base, void *top)
{
/* Align start address for the malloc code. Sigh. */
heapbase = (void *)(((uintptr_t)base + MALLOCALIGN_MASK) &
~MALLOCALIGN_MASK);
maxheap = (char *)top - (char *)heapbase;
}
char *
sbrk(int incr)
{
char *ret;
if (heapbase == 0)
panic("No heap setup");
if ((heapsize + incr) <= maxheap) {
ret = (char *)heapbase + heapsize;
bzero(ret, incr);
heapsize += incr;
return(ret);
}
errno = ENOMEM;
return((char *)-1);
}