1 /* msync -- Synchronize mapped memory to external storage.  Mach version.
2    Copyright (C) 2002-2022 Free Software Foundation, Inc.
3    This file is part of the GNU C Library.
4 
5    The GNU C Library is free software; you can redistribute it and/or
6    modify it under the terms of the GNU Lesser General Public
7    License as published by the Free Software Foundation; either
8    version 2.1 of the License, or (at your option) any later version.
9 
10    The GNU C Library is distributed in the hope that it will be useful,
11    but WITHOUT ANY WARRANTY; without even the implied warranty of
12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
13    Lesser General Public License for more details.
14 
15    You should have received a copy of the GNU Lesser General Public
16    License along with the GNU C Library; if not, see
17    <https://www.gnu.org/licenses/>.  */
18 
19 #include <sys/types.h>
20 #include <sys/mman.h>
21 #include <errno.h>
22 #include <mach.h>
23 #include <sysdep-cancel.h>
24 
25 /* Some Mach variants have vm_msync and some don't.  Those that have it
26    define the VM_SYNC_* bits when we include <mach/mach_types.h>.  */
27 
28 #ifndef VM_SYNC_SYNCHRONOUS
29 # include <misc/msync.c>
30 #else
31 
32 /* Synchronize the region starting at ADDR and extending LEN bytes with the
33    file it maps.  Filesystem operations on a file being mapped are
34    unpredictable before this is done.  */
35 
36 int
msync(void * addr,size_t len,int flags)37 msync (void *addr, size_t len, int flags)
38 {
39   vm_sync_t sync_flags = 0;
40   kern_return_t err;
41   int cancel_oldtype;
42 
43   if (flags & MS_SYNC)
44     sync_flags |= VM_SYNC_SYNCHRONOUS;
45   if (flags & MS_ASYNC)
46     sync_flags |= VM_SYNC_ASYNCHRONOUS;
47   if (flags & MS_INVALIDATE)
48     sync_flags |= VM_SYNC_INVALIDATE;
49 
50   cancel_oldtype = LIBC_CANCEL_ASYNC();
51   err = __vm_msync (__mach_task_self (),
52 		    (vm_address_t) addr, (vm_size_t) len, sync_flags);
53   LIBC_CANCEL_RESET (cancel_oldtype);
54   if (err)
55     {
56       errno = err;
57       return -1;
58     }
59   return 0;
60 }
61 #endif
62