1 /*
2 * Copyright (c) 2004 Apple Computer, Inc. All rights reserved.
3 *
4 * @APPLE_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. Please obtain a copy of the License at
10 * http://www.opensource.apple.com/apsl/ and read it before using this
11 * file.
12 *
13 * The Original Code and all software distributed under the License are
14 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
15 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
16 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
17 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
18 * Please see the License for the specific language governing rights and
19 * limitations under the License.
20 *
21 * @APPLE_LICENSE_HEADER_END@
22 */
23
24 #ifndef NO_SYSCALL_LEGACY
25
26 #define _NONSTD_SOURCE
27 #include <sys/cdefs.h>
28
29 #include <sys/types.h>
30 #include <sys/mman.h>
31 #include <mach/vm_param.h>
32 #include <mach/mach_init.h>
33 #include "stack_logging_internal.h"
34
35 /*
36 * Stub function to account for the differences in standard compliance
37 * while maintaining binary backward compatibility.
38 *
39 * This is only the legacy behavior.
40 */
41 extern int __munmap(void *, size_t);
42
43 int
munmap(void * addr,size_t len)44 munmap(void *addr, size_t len)
45 {
46 size_t offset;
47
48 if (len == 0) {
49 /*
50 * Standard compliance now requires the system to return EINVAL
51 * for munmap(addr, 0). Return success now to maintain
52 * backwards compatibility.
53 */
54 return 0;
55 }
56 /*
57 * Page-align "addr" since the system now requires it
58 * for standards compliance.
59 * Update "len" to reflect the adjustment and still cover the same area.
60 */
61 offset = ((uintptr_t) addr) & PAGE_MASK;
62 addr = (void *) (((uintptr_t) addr) & ~PAGE_MASK);
63 len += offset;
64
65 if (__syscall_logger) {
66 __syscall_logger(stack_logging_type_vm_deallocate, (uintptr_t)mach_task_self(), (uintptr_t)addr, len, 0, 0);
67 }
68
69 int result = __munmap(addr, len);
70
71 return result;
72 }
73 #endif /* NO_SYSCALL_LEGACY */
74