/
reentrant.go
77 lines (55 loc) · 840 Bytes
/
reentrant.go
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package common
import (
"sync"
)
type ReentrantMutex struct {
sync.Locker
mu sync.Mutex
current uint64
count int
}
func NewRentrantMutex() ReentrantMutex {
return ReentrantMutex{
mu: sync.Mutex{},
}
}
func (rm *ReentrantMutex) Lock() {
id := GoRoutineId()
for {
rm.mu.Lock()
if rm.current != 0 && rm.current != id {
rm.mu.Unlock()
continue
}
if rm.current == 0 {
rm.current = id
}
rm.count++
rm.mu.Unlock()
break
}
}
func (rm *ReentrantMutex) UnlockNow() {
rm.mu.Lock()
defer rm.mu.Unlock()
rm.current = 0
rm.count = 0
}
func (rm *ReentrantMutex) Unlock() {
id := GoRoutineId()
for {
rm.mu.Lock()
if rm.current != id {
rm.mu.Unlock()
continue
}
if rm.count > 0 {
rm.count--
}
if rm.count == 0 {
rm.current = 0
}
rm.mu.Unlock()
break
}
}