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1 /*

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 */

24 #ifndef NO_SYSCALL_LEGACY

26 #define _NONSTD_SOURCE

27 #include <sys/cdefs.h>

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"

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 */

 extern int __munmap(void *, size_t);

43 int

 munmap(void *addr, size_t len)

45 {

46 size_t offset;

         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 */

         offset = ((uintptr_t) addr) & PAGE_MASK;

         addr = (void *) (((uintptr_t) addr) & ~PAGE_MASK);

63 len += offset;

65 if (__syscall_logger) {

                 __syscall_logger(stack_logging_type_vm_deallocate, (uintptr_t)mach_task_self(), (uintptr_t)addr, len, 0, 0);

67 }

         int result = __munmap(addr, len);

71 return result;

72 }

73 #endif /* NO_SYSCALL_LEGACY */