projects / apple / libc.git / blame
| 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> | |
| 44 | ||
| 45 | static int sbrk_needs_init = TRUE; | |
| 46 | static vm_size_t sbrk_region_size = 4*1024*1024; /* Well, what should it be? */ | |
| 47 | static vm_address_t sbrk_curbrk; | |
| 48 | ||
| 49 | void *sbrk(int size) | |
| 50 | { | |
| 51 | kern_return_t ret; | |
| 52 | ||
| 53 | if (sbrk_needs_init) { | |
| 54 | sbrk_needs_init = FALSE; | |
| 55 | /* | |
| 56 | * Allocate a big region to simulate break region. | |
| 57 | */ | |
| 58 | ret = vm_allocate(mach_task_self(), &sbrk_curbrk, sbrk_region_size, | |
| 59 | VM_MAKE_TAG(VM_MEMORY_SBRK)|TRUE); | |
| 60 | if (ret != KERN_SUCCESS) { | |
| 61 | errno = ENOMEM; | |
| 62 | return((void *)-1); | |
| 63 | } | |
| 64 | } | |
| 65 | ||
| 66 | if (size <= 0) | |
| 67 | return((void *)sbrk_curbrk); | |
| 68 | else if (size > sbrk_region_size) { | |
| 69 | errno = ENOMEM; | |
| 70 | return((void *)-1); | |
| 71 | } | |
| 72 | sbrk_curbrk += size; | |
| 73 | sbrk_region_size -= size; | |
| 74 | return((void *)(sbrk_curbrk - size)); | |
| 75 | } | |
| 76 | ||
| 77 | void *brk(void *x) | |
| 78 | { | |
| 79 | errno = ENOMEM; | |
| 80 | return((void *)-1); | |
| 81 | } |