forked from tildetown/town
56 lines
981 B
Go
56 lines
981 B
Go
package lockingwriter
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import (
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"os"
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"time"
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"github.com/gofrs/flock"
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)
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// for now this package defines a writer for use with log.New(). It it intended to be used from the external ssh applications. This logger uses a file lock to allow all the various ssh applications to log to the same file.
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type LockingWriter struct {
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path string
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}
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const (
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fp = "/town/var/log/external.log"
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lp = "/town/var/log/log.lock"
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)
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func New() *LockingWriter {
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f, err := os.OpenFile(fp, os.O_EXCL|os.O_CREATE|os.O_WRONLY, 0660)
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if err != nil {
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panic(err)
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}
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defer f.Close()
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return &LockingWriter{
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path: fp,
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}
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}
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func (l *LockingWriter) Write(p []byte) (n int, err error) {
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fl := flock.New(lp)
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var locked bool
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for !locked {
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locked, err = fl.TryLock()
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if err != nil {
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return
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}
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time.Sleep(time.Second)
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}
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var f *os.File
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f, err = os.OpenFile(l.path, os.O_APPEND|os.O_WRONLY, 0600)
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if err != nil {
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return
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}
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defer f.Close()
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defer fl.Unlock()
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return f.Write(p)
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}
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