mirror of https://github.com/v2ray/v2ray-core
48 lines
907 B
Go
Executable File
48 lines
907 B
Go
Executable File
package signal
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import "sync"
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// Notifier is a utility for notifying changes. The change producer may notify changes multiple time, and the consumer may get notified asynchronously.
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type Notifier struct {
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sync.Mutex
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waiters []chan struct{}
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notCosumed bool
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}
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// NewNotifier creates a new Notifier.
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func NewNotifier() *Notifier {
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return &Notifier{}
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}
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// Signal signals a change, usually by producer. This method never blocks.
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func (n *Notifier) Signal() {
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n.Lock()
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defer n.Unlock()
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if len(n.waiters) == 0 {
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n.notCosumed = true
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return
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}
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for _, w := range n.waiters {
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close(w)
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}
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n.waiters = make([]chan struct{}, 0, 8)
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}
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// Wait returns a channel for waiting for changes.
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func (n *Notifier) Wait() <-chan struct{} {
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n.Lock()
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defer n.Unlock()
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w := make(chan struct{})
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if n.notCosumed {
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n.notCosumed = false
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close(w)
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return w
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}
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n.waiters = append(n.waiters, w)
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return w
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}
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