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
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
|
#+private
#+build openbsd
package sync
import "core:c"
import "core:time"
FUTEX_WAIT :: 1
FUTEX_WAKE :: 2
FUTEX_PRIVATE_FLAG :: 128
FUTEX_WAIT_PRIVATE :: (FUTEX_WAIT | FUTEX_PRIVATE_FLAG)
FUTEX_WAKE_PRIVATE :: (FUTEX_WAKE | FUTEX_PRIVATE_FLAG)
ETIMEDOUT :: 60
foreign import libc "system:c"
foreign libc {
@(link_name="futex")
_unix_futex :: proc "c" (f: ^Futex, op: c.int, val: u32, timeout: rawptr) -> c.int ---
@(link_name="__errno") __errno :: proc() -> ^int ---
}
_futex_wait :: proc "contextless" (f: ^Futex, expected: u32) -> bool {
res := _unix_futex(f, FUTEX_WAIT_PRIVATE, expected, nil)
if res != -1 {
return true
}
if __errno()^ == ETIMEDOUT {
return false
}
panic_contextless("futex_wait failure")
}
_futex_wait_with_timeout :: proc "contextless" (f: ^Futex, expected: u32, duration: time.Duration) -> bool {
if duration <= 0 {
return false
}
timespec_t :: struct {
tv_sec: c.long,
tv_nsec: c.long,
}
res := _unix_futex(f, FUTEX_WAIT_PRIVATE, expected, ×pec_t{
tv_sec = (c.long)(duration/1e9),
tv_nsec = (c.long)(duration%1e9),
})
if res != -1 {
return true
}
if __errno()^ == ETIMEDOUT {
return false
}
panic_contextless("futex_wait_with_timeout failure")
}
_futex_signal :: proc "contextless" (f: ^Futex) {
res := _unix_futex(f, FUTEX_WAKE_PRIVATE, 1, nil)
if res == -1 {
panic_contextless("futex_wake_single failure")
}
}
_futex_broadcast :: proc "contextless" (f: ^Futex) {
res := _unix_futex(f, FUTEX_WAKE_PRIVATE, u32(max(i32)), nil)
if res == -1 {
panic_contextless("_futex_wake_all failure")
}
}
|
