]> code.delx.au - pulseaudio/blob - src/pulsecore/atomic.h
add a tiny wrapper around libatomic_ops: pa_atomic_int_t and pa_atomit_ptr_t.
[pulseaudio] / src / pulsecore / atomic.h
1 #ifndef foopulseatomichfoo
2 #define foopulseatomichfoo
3
4 /* $Id$ */
5
6 /***
7 This file is part of PulseAudio.
8
9 PulseAudio is free software; you can redistribute it and/or modify
10 it under the terms of the GNU Lesser General Public License as
11 published by the Free Software Foundation; either version 2 of the
12 License, or (at your option) any later version.
13
14 PulseAudio is distributed in the hope that it will be useful, but
15 WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
17 General Public License for more details.
18
19 You should have received a copy of the GNU Lesser General Public
20 License along with PulseAudio; if not, write to the Free Software
21 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
22 USA.
23 ***/
24
25 #include <atomic_ops.h>
26
27 /* atomic_ops guarantees us that sizeof(AO_t) == sizeof(void*).
28 *
29 * It is not guaranteed however, that sizeof(AO_t) == sizeof(size_t).
30 * however very likely. */
31
32 typedef struct pa_atomic_int {
33 volatile AO_t value;
34 } pa_atomic_int_t;
35
36 /* For now we do only full memory barriers. Eventually we might want
37 * to support more elaborate memory barriers, in which case we will add
38 * suffixes to the function names */
39
40 static inline int pa_atomic_load(const pa_atomic_int_t *a) {
41 return (int) AO_load_full((AO_t*) &a->value);
42 }
43
44 static inline void pa_atomic_store(pa_atomic_int_t *a, int i) {
45 AO_store_full(&a->value, (AO_t) i);
46 }
47
48 static inline int pa_atomic_add(pa_atomic_int_t *a, int i) {
49 return AO_fetch_and_add_full(&a->value, (AO_t) i);
50 }
51
52 static inline int pa_atomic_inc(pa_atomic_int_t *a) {
53 return AO_fetch_and_add1_full(&a->value);
54 }
55
56 static inline int pa_atomic_dec(pa_atomic_int_t *a) {
57 return AO_fetch_and_sub1_full(&a->value);
58 }
59
60 static inline int pa_atomic_cmpxchg(pa_atomic_int_t *a, int old_i, int new_i) {
61 return AO_compare_and_swap_full(&a->value, old_i, new_i);
62 }
63
64 typedef struct pa_atomic_ptr {
65 volatile AO_t value;
66 } pa_atomic_ptr_t;
67
68 static inline void* pa_atomic_ptr_load(const pa_atomic_ptr_t *a) {
69 return (void*) AO_load_full((AO_t*) &a->value);
70 }
71
72 static inline void pa_atomic_ptr_store(pa_atomic_ptr_t *a, void *p) {
73 AO_store_full(&a->value, (AO_t) p);
74 }
75
76 static inline int pa_atomic_ptr_cmpxchg(pa_atomic_ptr_t *a, void *old_p, void* new_p) {
77 return AO_compare_and_swap_full(&a->value, (AO_t) old_p, (AO_t) new_p);
78 }
79
80 #endif