add lock around tail.reader to prevent race (#1)

phemmer · danielnelson · commit b4143c2b9991 · 2017-03-29T13:28:55.000-07:00
diff --git a/tail.go b/tail.go
@@ -391,12 +391,14 @@ func (tail *Tail) waitForChanges() error {
 }
 
 func (tail *Tail) openReader() {
+	tail.lk.Lock()
 	if tail.MaxLineSize > 0 {
 		// add 2 to account for newline characters
 		tail.reader = bufio.NewReaderSize(tail.file, tail.MaxLineSize+2)
 	} else {
 		tail.reader = bufio.NewReader(tail.file)
 	}
+	tail.lk.Unlock()
 }
 
 func (tail *Tail) seekEnd() error {

Original file line number	Diff line number	Diff line change
`@@ -391,12 +391,14 @@ func (tail *Tail) waitForChanges() error {`
`391`	`391`	`}`
`392`	`392`
`393`	`393`	`func (tail *Tail) openReader() {`
	`394`	`+ tail.lk.Lock()`
`394`	`395`	`if tail.MaxLineSize > 0 {`
`395`	`396`	`// add 2 to account for newline characters`
`396`	`397`	`tail.reader = bufio.NewReaderSize(tail.file, tail.MaxLineSize+2)`
`397`	`398`	`} else {`
`398`	`399`	`tail.reader = bufio.NewReader(tail.file)`
`399`	`400`	`}`
	`401`	`+ tail.lk.Unlock()`
`400`	`402`	`}`
`401`	`403`
`402`	`404`	`func (tail *Tail) seekEnd() error {`