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|
package buffer
import (
"sync"
)
type Outbound struct {
val int
err error
*sync.Cond
}
func NewOutbound(size int) *Outbound {
return &Outbound{val: size, Cond: sync.NewCond(new(sync.Mutex))}
}
func (b *Outbound) Increment(inc int) {
b.L.Lock()
b.val += inc
b.Broadcast()
b.L.Unlock()
}
func (b *Outbound) SetError(err error) {
b.L.Lock()
b.err = err
b.Broadcast()
b.L.Unlock()
}
func (b *Outbound) Decrement(dec int) (ret int, err error) {
if dec == 0 {
return
}
b.L.Lock()
for {
if b.err != nil {
err = b.err
break
}
if b.val > 0 {
if dec > b.val {
ret = b.val
b.val = 0
break
} else {
b.val -= dec
ret = dec
break
}
} else {
b.Wait()
}
}
b.L.Unlock()
return
}
|
