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1/*
2 * Copyright (c) 1999 Apple Computer, Inc. All rights reserved.
3 *
4 * @APPLE_LICENSE_HEADER_START@
5 *
734aad71 6 * Copyright (c) 1999-2003 Apple Computer, Inc. All Rights Reserved.
e9ce8d39 7 *
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8 * This file contains Original Code and/or Modifications of Original Code
9 * as defined in and that are subject to the Apple Public Source License
10 * Version 2.0 (the 'License'). You may not use this file except in
11 * compliance with the License. Please obtain a copy of the License at
12 * http://www.opensource.apple.com/apsl/ and read it before using this
13 * file.
14 *
15 * The Original Code and all software distributed under the License are
16 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
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17 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
18 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
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19 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
20 * Please see the License for the specific language governing rights and
21 * limitations under the License.
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22 *
23 * @APPLE_LICENSE_HEADER_END@
24 */
25/*
26 * File: sbrk.c
27 *
28 * Unix compatibility for sbrk system call.
29 *
30 * HISTORY
31 * 09-Mar-90 Gregg Kellogg (gk) at NeXT.
32 * include <kern/mach_interface.h> instead of <kern/mach.h>
33 *
34 * 14-Feb-89 Avadis Tevanian (avie) at NeXT.
35 * Total rewrite using a fixed area of VM from break region.
36 */
37
38#include <mach/mach.h> /* for vm_allocate, vm_offset_t */
39#include <mach/vm_statistics.h>
40#include <sys/types.h> /* for caddr_t */
41
42static int sbrk_needs_init = TRUE;
43static vm_size_t sbrk_region_size = 4*1024*1024; /* Well, what should it be? */
44static vm_address_t sbrk_curbrk;
45
46caddr_t sbrk(size)
47 int size;
48{
49 vm_offset_t addr;
50 kern_return_t ret;
51 caddr_t ocurbrk;
52 extern int end;
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 return((caddr_t)-1);
63 }
64
65 if (size <= 0)
66 return((caddr_t)sbrk_curbrk);
67 sbrk_curbrk += size;
68 sbrk_region_size -= size;
69 if (sbrk_region_size < 0)
70 return((caddr_t)-1);
71 return((caddr_t)(sbrk_curbrk - size));
72}
73
74caddr_t brk(x)
75 caddr_t x;
76{
77 return((caddr_t)-1);
78}
79