xref: /xnu-11215.61.5/libsyscall/wrappers/legacy/munmap.c (revision 4f1223e81cd707a65cc109d0b8ad6653699da3c4)
1*4f1223e8SApple OSS Distributions /*
2*4f1223e8SApple OSS Distributions  * Copyright (c) 2004 Apple Computer, Inc. All rights reserved.
3*4f1223e8SApple OSS Distributions  *
4*4f1223e8SApple OSS Distributions  * @APPLE_LICENSE_HEADER_START@
5*4f1223e8SApple OSS Distributions  *
6*4f1223e8SApple OSS Distributions  * This file contains Original Code and/or Modifications of Original Code
7*4f1223e8SApple OSS Distributions  * as defined in and that are subject to the Apple Public Source License
8*4f1223e8SApple OSS Distributions  * Version 2.0 (the 'License'). You may not use this file except in
9*4f1223e8SApple OSS Distributions  * compliance with the License. Please obtain a copy of the License at
10*4f1223e8SApple OSS Distributions  * http://www.opensource.apple.com/apsl/ and read it before using this
11*4f1223e8SApple OSS Distributions  * file.
12*4f1223e8SApple OSS Distributions  *
13*4f1223e8SApple OSS Distributions  * The Original Code and all software distributed under the License are
14*4f1223e8SApple OSS Distributions  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
15*4f1223e8SApple OSS Distributions  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
16*4f1223e8SApple OSS Distributions  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
17*4f1223e8SApple OSS Distributions  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
18*4f1223e8SApple OSS Distributions  * Please see the License for the specific language governing rights and
19*4f1223e8SApple OSS Distributions  * limitations under the License.
20*4f1223e8SApple OSS Distributions  *
21*4f1223e8SApple OSS Distributions  * @APPLE_LICENSE_HEADER_END@
22*4f1223e8SApple OSS Distributions  */
23*4f1223e8SApple OSS Distributions 
24*4f1223e8SApple OSS Distributions #ifndef NO_SYSCALL_LEGACY
25*4f1223e8SApple OSS Distributions 
26*4f1223e8SApple OSS Distributions #define _NONSTD_SOURCE
27*4f1223e8SApple OSS Distributions #include <sys/cdefs.h>
28*4f1223e8SApple OSS Distributions 
29*4f1223e8SApple OSS Distributions #include <sys/types.h>
30*4f1223e8SApple OSS Distributions #include <sys/mman.h>
31*4f1223e8SApple OSS Distributions #include <mach/vm_param.h>
32*4f1223e8SApple OSS Distributions #include <mach/mach_init.h>
33*4f1223e8SApple OSS Distributions #include "stack_logging_internal.h"
34*4f1223e8SApple OSS Distributions 
35*4f1223e8SApple OSS Distributions /*
36*4f1223e8SApple OSS Distributions  * Stub function to account for the differences in standard compliance
37*4f1223e8SApple OSS Distributions  * while maintaining binary backward compatibility.
38*4f1223e8SApple OSS Distributions  *
39*4f1223e8SApple OSS Distributions  * This is only the legacy behavior.
40*4f1223e8SApple OSS Distributions  */
41*4f1223e8SApple OSS Distributions extern int __munmap(void *, size_t);
42*4f1223e8SApple OSS Distributions 
43*4f1223e8SApple OSS Distributions int
munmap(void * addr,size_t len)44*4f1223e8SApple OSS Distributions munmap(void *addr, size_t len)
45*4f1223e8SApple OSS Distributions {
46*4f1223e8SApple OSS Distributions 	size_t  offset;
47*4f1223e8SApple OSS Distributions 
48*4f1223e8SApple OSS Distributions 	if (len == 0) {
49*4f1223e8SApple OSS Distributions 		/*
50*4f1223e8SApple OSS Distributions 		 * Standard compliance now requires the system to return EINVAL
51*4f1223e8SApple OSS Distributions 		 * for munmap(addr, 0).  Return success now to maintain
52*4f1223e8SApple OSS Distributions 		 * backwards compatibility.
53*4f1223e8SApple OSS Distributions 		 */
54*4f1223e8SApple OSS Distributions 		return 0;
55*4f1223e8SApple OSS Distributions 	}
56*4f1223e8SApple OSS Distributions 	/*
57*4f1223e8SApple OSS Distributions 	 * Page-align "addr" since the system now requires it
58*4f1223e8SApple OSS Distributions 	 * for standards compliance.
59*4f1223e8SApple OSS Distributions 	 * Update "len" to reflect the adjustment and still cover the same area.
60*4f1223e8SApple OSS Distributions 	 */
61*4f1223e8SApple OSS Distributions 	offset = ((uintptr_t) addr) & PAGE_MASK;
62*4f1223e8SApple OSS Distributions 	addr = (void *) (((uintptr_t) addr) & ~PAGE_MASK);
63*4f1223e8SApple OSS Distributions 	len += offset;
64*4f1223e8SApple OSS Distributions 
65*4f1223e8SApple OSS Distributions 	if (__syscall_logger) {
66*4f1223e8SApple OSS Distributions 		__syscall_logger(stack_logging_type_vm_deallocate, (uintptr_t)mach_task_self(), (uintptr_t)addr, len, 0, 0);
67*4f1223e8SApple OSS Distributions 	}
68*4f1223e8SApple OSS Distributions 
69*4f1223e8SApple OSS Distributions 	int result = __munmap(addr, len);
70*4f1223e8SApple OSS Distributions 
71*4f1223e8SApple OSS Distributions 	return result;
72*4f1223e8SApple OSS Distributions }
73*4f1223e8SApple OSS Distributions #endif /* NO_SYSCALL_LEGACY */
74