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