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Commit	Line	Data
1f2f436a A	1	/*
	2	* Copyright (c) 1999-2010 Apple Inc. All rights reserved.
	3	*
	4	* @APPLE_OSREFERENCE_LICENSE_HEADER_START@
	5	*
	6	* This file contains Original Code and/or Modifications of Original Code
	7	* as defined in and that are subject to the Apple Public Source License
	8	* Version 2.0 (the 'License'). You may not use this file except in
	9	* compliance with the License. The rights granted to you under the License
	10	* may not be used to create, or enable the creation or redistribution of,
	11	* unlawful or unlicensed copies of an Apple operating system, or to
	12	* circumvent, violate, or enable the circumvention or violation of, any
	13	* terms of an Apple operating system software license agreement.
	14	*
	15	* Please obtain a copy of the License at
	16	* http://www.opensource.apple.com/apsl/ and read it before using this file.
	17	*
	18	* The Original Code and all software distributed under the License are
	19	* distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
	20	* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
	21	* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
	22	* FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
	23	* Please see the License for the specific language governing rights and
	24	* limitations under the License.
	25	*
	26	* @APPLE_OSREFERENCE_LICENSE_HEADER_END@
	27	*/
	28	/*
	29	* File: brk.c
	30	*
	31	* Unix compatibility for sbrk system call.
	32	*
	33	* HISTORY
	34	* 09-Mar-90 Gregg Kellogg (gk) at NeXT.
	35	* include <kern/mach_interface.h> instead of <kern/mach.h>
	36	*
	37	* 14-Feb-89 Avadis Tevanian (avie) at NeXT.
	38	* Total rewrite using a fixed area of VM from break region.
	39	*/
	40
	41	#include <mach/mach.h> /* for vm_allocate, vm_offset_t */
	42	#include <mach/vm_statistics.h>
	43	#include <errno.h>
6465356a	44	#include <unistd.h>
1f2f436a A	45
	46	static int sbrk_needs_init = TRUE;
	47	static vm_size_t sbrk_region_size = 410241024; /* Well, what should it be? */
	48	static vm_address_t sbrk_curbrk;
	49
	50	void *sbrk(int size)
	51	{
	52	kern_return_t ret;
	53
	54	if (sbrk_needs_init) {
	55	sbrk_needs_init = FALSE;
	56	/*
	57	* Allocate a big region to simulate break region.
	58	*/
	59	ret = vm_allocate(mach_task_self(), &sbrk_curbrk, sbrk_region_size,
	60	VM_MAKE_TAG(VM_MEMORY_SBRK)\|TRUE);
	61	if (ret != KERN_SUCCESS) {
	62	errno = ENOMEM;
	63	return((void *)-1);
	64	}
	65	}
	66
	67	if (size <= 0)
	68	return((void *)sbrk_curbrk);
	69	else if (size > sbrk_region_size) {
	70	errno = ENOMEM;
	71	return((void *)-1);
	72	}
	73	sbrk_curbrk += size;
	74	sbrk_region_size -= size;
	75	return((void *)(sbrk_curbrk - size));
	76	}
	77
6465356a	78	void brk(const void x)
1f2f436a A	79	{
	80	errno = ENOMEM;
	81	return((void *)-1);
	82	}