1 package xcontext
2
3 import (
4 "context"
5 "fmt"
6 )
7
8 type Mutex struct {
9 ch chan struct{}
10 }
11
12 func NewMutex() *Mutex {
13 return &Mutex{
14 ch: make(chan struct{}, 1),
15 }
16 }
17
18 func (m *Mutex) TryLock() bool {
19 select {
20 case m.ch <- struct{}{}:
21 return true
22 default:
23 return false
24 }
25 }
26
27 func (m *Mutex) Lock(ctx context.Context) error {
28 select {
29 case <-ctx.Done():
30 return fmt.Errorf("failed to acquire lock: %w", ctx.Err())
31 case m.ch <- struct{}{}:
32 return nil
33 }
34 }
35
36 func (m *Mutex) Unlock() {
37 select {
38 case <-m.ch:
39 default:
40 panic("xcontext.Mutex: Unlock before Lock")
41 }
42 }
43
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