/
base_lock.go
71 lines (63 loc) · 1.54 KB
/
base_lock.go
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package gocache
import (
"fmt"
"time"
)
type baseLock struct {
lock
}
// Get attempts to acquire a lock. If acquired, fn will be invoked and the lock will be safely release once
// the invocation either succeeds or errors
func (l *baseLock) Get(fn func() error) (acquired bool, err error) {
acquired, err = l.Acquire()
if err != nil {
return false, err
}
if !acquired {
return acquired, nil
}
defer func() {
if _, releaseErr := l.Release(); releaseErr == nil {
return
} else if err != nil {
err = fmt.Errorf("gocache: %v: %v", err.Error(), releaseErr)
} else {
err = releaseErr
}
}()
err = fn()
return acquired, err
}
// Block will attempt to acquire a lock for the specified "wait" time. If acquired, fn will be invoked and
// the lock will be safely release once the invocation either succeeds or errors. The interval variable
// will be used as the wait duration between attempts to acquire the lock
func (l *baseLock) Block(interval, wait time.Duration, fn func() error) (acquired bool, err error) {
starting := time.Now()
for {
acquired, err = l.Acquire()
if err != nil {
return false, err
}
if acquired {
break
}
time.Sleep(interval)
if time.Now().Add(-wait).After(starting) {
return false, ErrBlockWaitTimeout
}
}
if !acquired {
return acquired, nil
}
defer func() {
if _, releaseErr := l.Release(); releaseErr == nil {
return
} else if err != nil {
err = fmt.Errorf("gocache: %v: %v", err.Error(), releaseErr)
} else {
err = releaseErr
}
}()
err = fn()
return acquired, err
}