1 /* Macros for copying by pages; used in memcpy, memmove.  Mach version.
2    Copyright (C) 1995-2022 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 <mach.h>
20 
21 /* Threshold at which vm_copy is more efficient than well-optimized copying
22    by words.  */
23 #define PAGE_COPY_THRESHOLD		(16384)
24 
25 #define PAGE_SIZE		__vm_page_size
26 #define PAGE_COPY_FWD(dstp, srcp, nbytes_left, nbytes)			      \
27   ((nbytes_left) = ((nbytes)						      \
28 		    - (__vm_copy (__mach_task_self (),			      \
29 				  (vm_address_t) srcp, trunc_page (nbytes),   \
30 				  (vm_address_t) dstp) == KERN_SUCCESS	      \
31 		       ? trunc_page (nbytes)				      \
32 		       : 0)))
33