33 lines
473 B
Go
33 lines
473 B
Go
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package idgen
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import (
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"sync"
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"time"
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)
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var (
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lock sync.Mutex
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ts uint64 = uint64(time.Now().Unix())
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counter uint64 = 1
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counterMax uint64 = 1 << 28
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)
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// Next can generate ~268M ints per second for ~1000 years.
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func Next() uint64 {
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lock.Lock()
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defer lock.Unlock()
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tt := uint64(time.Now().Unix())
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if tt > ts {
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ts = tt
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counter = 1
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} else {
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counter++
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if counter == counterMax {
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panic("Too many IDs.")
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}
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}
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return ts<<28 + counter
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}
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