2013-11-10 17:31:50 +08:00
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package sequence
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2014-04-17 14:43:27 +08:00
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import (
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"sync"
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)
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2013-11-10 17:31:50 +08:00
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// just for testing
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type MemorySequencer struct {
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2014-04-17 14:43:27 +08:00
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counter uint64
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sequenceLock sync.Mutex
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2013-11-10 17:31:50 +08:00
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}
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func NewMemorySequencer() (m *MemorySequencer) {
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m = &MemorySequencer{counter: 1}
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return
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}
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2019-10-30 15:49:58 +08:00
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func (m *MemorySequencer) NextFileId(count uint64) uint64 {
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2014-04-17 14:43:27 +08:00
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m.sequenceLock.Lock()
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defer m.sequenceLock.Unlock()
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2013-11-10 17:31:50 +08:00
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ret := m.counter
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2019-10-30 15:49:58 +08:00
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m.counter += count
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return ret
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2013-11-10 17:31:50 +08:00
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}
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2014-04-17 14:43:27 +08:00
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func (m *MemorySequencer) SetMax(seenValue uint64) {
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m.sequenceLock.Lock()
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defer m.sequenceLock.Unlock()
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if m.counter <= seenValue {
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m.counter = seenValue + 1
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}
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}
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func (m *MemorySequencer) Peek() uint64 {
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return m.counter
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}
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