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
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
|
package mutexes
import (
"sync"
"time"
"git.iim.gay/grufwub/go-nowish"
)
// TimeoutMutex defines a Mutex with timeouts on locks
type TimeoutMutex interface {
Mutex
// LockFunc is functionally the same as Lock(), but allows setting a custom hook called on timeout
LockFunc(func()) func()
}
// TimeoutRWMutex defines a RWMutex with timeouts on locks
type TimeoutRWMutex interface {
RWMutex
// LockFunc is functionally the same as Lock(), but allows setting a custom hook called on timeout
LockFunc(func()) func()
// RLockFunc is functionally the same as RLock(), but allows setting a custom hook called on timeout
RLockFunc(func()) func()
}
// WithTimeout wraps the supplied Mutex to add a timeout
func WithTimeout(mu Mutex, d time.Duration) TimeoutMutex {
return &timeoutMutex{mu: mu, d: d}
}
// WithTimeoutRW wraps the supplied RWMutex to add read/write timeouts
func WithTimeoutRW(mu RWMutex, rd, wd time.Duration) TimeoutRWMutex {
return &timeoutRWMutex{mu: mu, rd: rd, wd: wd}
}
// timeoutMutex wraps a Mutex with timeout
type timeoutMutex struct {
mu Mutex // mu is the wrapped mutex
d time.Duration // d is the timeout duration
}
func (mu *timeoutMutex) Lock() func() {
return mu.LockFunc(func() { panic("timed out") })
}
func (mu *timeoutMutex) LockFunc(fn func()) func() {
return mutexTimeout(mu.d, mu.mu.Lock(), fn)
}
// TimeoutRWMutex wraps a RWMutex with timeouts
type timeoutRWMutex struct {
mu RWMutex // mu is the wrapped rwmutex
rd time.Duration // rd is the rlock timeout duration
wd time.Duration // wd is the lock timeout duration
}
func (mu *timeoutRWMutex) Lock() func() {
return mu.LockFunc(func() { panic("timed out") })
}
func (mu *timeoutRWMutex) LockFunc(fn func()) func() {
return mutexTimeout(mu.wd, mu.mu.Lock(), fn)
}
func (mu *timeoutRWMutex) RLock() func() {
return mu.RLockFunc(func() { panic("timed out") })
}
func (mu *timeoutRWMutex) RLockFunc(fn func()) func() {
return mutexTimeout(mu.rd, mu.mu.RLock(), fn)
}
// timeoutPool provides nowish.Timeout objects for timeout mutexes
var timeoutPool = sync.Pool{
New: func() interface{} {
return nowish.NewTimeout()
},
}
// mutexTimeout performs a timed unlock, calling supplied fn if timeout is reached
func mutexTimeout(d time.Duration, unlock func(), fn func()) func() {
if d < 1 {
// No timeout, just unlock
return unlock
}
// Acquire timeout obj
t := timeoutPool.Get().(nowish.Timeout)
// Start the timeout with hook
t.Start(d, fn)
// Return func cancelling timeout,
// replacing Timeout in pool and
// finally unlocking mutex
return func() {
t.Cancel()
timeoutPool.Put(t)
unlock()
}
}
|
