File: atomic-machine.h

package info (click to toggle)
glibc 2.24-10
  • links: PTS, VCS
  • area: main
  • in suites: stretch
  • size: 223,412 kB
  • sloc: ansic: 991,967; asm: 261,800; sh: 10,385; makefile: 9,710; cpp: 4,169; python: 3,971; perl: 2,254; awk: 1,753; pascal: 1,521; yacc: 291; sed: 80
file content (42 lines) | stat: -rw-r--r-- 1,751 bytes parent folder | download | duplicates (4)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
/* Copyright (C) 2003-2016 Free Software Foundation, Inc.
   This file is part of the GNU C Library.
   Contributed by Ulrich Drepper <drepper@redhat.com>, 2003.

   The GNU C Library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Lesser General Public
   License as published by the Free Software Foundation; either
   version 2.1 of the License, or (at your option) any later version.

   The GNU C Library is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   Lesser General Public License for more details.

   You should have received a copy of the GNU Lesser General Public
   License along with the GNU C Library; if not, see
   <http://www.gnu.org/licenses/>.  */

#ifndef _ATOMIC_MACHINE_H
#define _ATOMIC_MACHINE_H	1

/* We have by default no support for atomic operations.  So define
   them non-atomic.  If this is a problem somebody will have to come
   up with real definitions.  */

/* The only basic operation needed is compare and exchange.  */
#define atomic_compare_and_exchange_val_acq(mem, newval, oldval) \
  ({ __typeof (mem) __gmemp = (mem);				      \
     __typeof (*mem) __gret = *__gmemp;				      \
     __typeof (*mem) __gnewval = (newval);			      \
								      \
     if (__gret == (oldval))					      \
       *__gmemp = __gnewval;					      \
     __gret; })

#define atomic_compare_and_exchange_bool_acq(mem, newval, oldval) \
  ({ __typeof (mem) __gmemp = (mem);				      \
     __typeof (*mem) __gnewval = (newval);			      \
								      \
     *__gmemp == (oldval) ? (*__gmemp = __gnewval, 0) : 1; })

#endif	/* atomic-machine.h */