139665Smsmith/*- 239665Smsmith * Copyright (c) 1998 Michael Smith 339665Smsmith * All rights reserved. 439665Smsmith * 539665Smsmith * Redistribution and use in source and binary forms, with or without 639665Smsmith * modification, are permitted provided that the following conditions 739665Smsmith * are met: 839665Smsmith * 1. Redistributions of source code must retain the above copyright 939665Smsmith * notice, this list of conditions and the following disclaimer. 1039665Smsmith * 2. Redistributions in binary form must reproduce the above copyright 1139665Smsmith * notice, this list of conditions and the following disclaimer in the 1239665Smsmith * documentation and/or other materials provided with the distribution. 1339665Smsmith * 1439665Smsmith * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 1539665Smsmith * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 1639665Smsmith * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 1739665Smsmith * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 1839665Smsmith * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 1939665Smsmith * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 2039665Smsmith * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 2139665Smsmith * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 2239665Smsmith * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 2339665Smsmith * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 2439665Smsmith * SUCH DAMAGE. 2539665Smsmith */ 2639665Smsmith 2784221Sdillon#include <sys/cdefs.h> 2884221Sdillon__FBSDID("$FreeBSD$"); 2984221Sdillon 3039665Smsmith/* 3139665Smsmith * Minimal sbrk() emulation required for malloc support. 3239665Smsmith */ 3339665Smsmith 3439665Smsmith#include <string.h> 3539665Smsmith#include "stand.h" 36269101Sian#include "zalloc_defs.h" 3739665Smsmith 3839665Smsmithstatic size_t maxheap, heapsize = 0; 3939665Smsmithstatic void *heapbase; 4039665Smsmith 4139665Smsmithvoid 4239665Smsmithsetheap(void *base, void *top) 4339665Smsmith{ 44269101Sian /* Align start address for the malloc code. Sigh. */ 45269101Sian heapbase = (void *)(((uintptr_t)base + MALLOCALIGN_MASK) & 46269101Sian ~MALLOCALIGN_MASK); 47136093Sstefanf maxheap = (char *)top - (char *)heapbase; 4839665Smsmith} 4939665Smsmith 5039665Smsmithchar * 5139665Smsmithsbrk(int incr) 5239665Smsmith{ 5339665Smsmith char *ret; 5439665Smsmith 5539665Smsmith if ((heapsize + incr) <= maxheap) { 56136093Sstefanf ret = (char *)heapbase + heapsize; 5739665Smsmith bzero(ret, incr); 5839665Smsmith heapsize += incr; 5939665Smsmith return(ret); 6039665Smsmith } 6139665Smsmith errno = ENOMEM; 6239665Smsmith return((char *)-1); 6339665Smsmith} 6439665Smsmith 65