50 lines
655 B
Go
50 lines
655 B
Go
package stores
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import (
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"context"
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"sync"
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)
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// like sync.Cond, but broadcast-only and with context handling
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type ctxCond struct {
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notif chan struct{}
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l sync.Locker
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lk sync.Mutex
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}
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func newCtxCond(l sync.Locker) *ctxCond {
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return &ctxCond{
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l: l,
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}
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}
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func (c *ctxCond) Broadcast() {
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c.lk.Lock()
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if c.notif != nil {
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close(c.notif)
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c.notif = nil
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}
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c.lk.Unlock()
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}
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func (c *ctxCond) Wait(ctx context.Context) error {
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c.lk.Lock()
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if c.notif == nil {
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c.notif = make(chan struct{})
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}
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wait := c.notif
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c.lk.Unlock()
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c.l.Unlock()
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defer c.l.Lock()
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select {
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case <-wait:
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return nil
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case <-ctx.Done():
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return ctx.Err()
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}
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}
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