59 lines
1.2 KiB
Go
59 lines
1.2 KiB
Go
package meta
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import (
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"encoding/binary"
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"go.etcd.io/bbolt"
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)
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var shardCounterKey = []byte("counter")
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// ObjectCounter returns object count that metabase has
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// tracked since it was opened and initialized.
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//
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// Returns only the errors that do not allow reading counter
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// in Bolt database.
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func (db *DB) ObjectCounter() (counter uint64, err error) {
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err = db.boltDB.View(func(tx *bbolt.Tx) error {
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b := tx.Bucket(shardInfoBucket)
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if b != nil {
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data := b.Get(shardCounterKey)
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if len(data) == 8 {
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counter = binary.LittleEndian.Uint64(data)
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}
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}
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return nil
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})
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return
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}
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// updateCounter updates the object counter. Tx MUST be writable.
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// If inc == `true`, increases the counter, decreases otherwise.
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func (db *DB) updateCounter(tx *bbolt.Tx, delta uint64, inc bool) error {
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b := tx.Bucket(shardInfoBucket)
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if b == nil {
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return nil
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}
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var counter uint64
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data := b.Get(shardCounterKey)
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if len(data) == 8 {
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counter = binary.LittleEndian.Uint64(data)
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}
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if inc {
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counter += delta
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} else if counter <= delta {
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counter = 0
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} else {
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counter -= delta
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}
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newCounter := make([]byte, 8)
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binary.LittleEndian.PutUint64(newCounter, counter)
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return b.Put(shardCounterKey, newCounter)
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}
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