34 lines
883 B
Go
34 lines
883 B
Go
package database
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import (
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"fmt"
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"hash/crc32"
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"strings"
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"sync/atomic"
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)
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const advisoryLockIDSalt uint = 1486364155
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// GenerateAdvisoryLockId inspired by rails migrations, see https://goo.gl/8o9bCT
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func GenerateAdvisoryLockId(databaseName string, additionalNames ...string) (string, error) { // nolint: golint
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if len(additionalNames) > 0 {
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databaseName = strings.Join(append(additionalNames, databaseName), "\x00")
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}
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sum := crc32.ChecksumIEEE([]byte(databaseName))
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sum = sum * uint32(advisoryLockIDSalt)
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return fmt.Sprint(sum), nil
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}
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// CasRestoreOnErr CAS wrapper to automatically restore the lock state on error
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func CasRestoreOnErr(lock *atomic.Bool, o, n bool, casErr error, f func() error) error {
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if !lock.CompareAndSwap(o, n) {
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return casErr
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}
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if err := f(); err != nil {
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// Automatically unlock/lock on error
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lock.Store(o)
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return err
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}
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return nil
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}
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