8019: Use tl.stopping channel instead of tl.flush to signal Close. Use unbuffered...

diff --git a/services/crunch-run/logging.go b/services/crunch-run/logging.go
index 3aedf51779838c9359fb8c0d8071a7600f891237..96feb5faab53c8344a643054bd98605adb6ac807 100644 (file)
--- a/services/crunch-run/logging.go
+++ b/services/crunch-run/logging.go
@@ -34,9 +34,10 @@ type ThrottledLogger struct {
        *log.Logger
        buf *bytes.Buffer
        sync.Mutex
-       writer  io.WriteCloser
-       flush   chan struct{}
-       stopped chan struct{}
+       writer   io.WriteCloser
+       flush    chan struct{}
+       stopped  chan struct{}
+       stopping chan struct{}
        Timestamper
        Immediate    *log.Logger
        pendingFlush bool
@@ -97,9 +98,10 @@ func (tl *ThrottledLogger) flusher() {
        defer ticker.Stop()
        for stopping := false; !stopping; {
                select {
-               case _, open := <-tl.flush:
-                       // if !open, will flush tl.buf and exit the loop
-                       stopping = !open
+               case <-tl.stopping:
+                       // flush tl.buf and exit the loop
+                       stopping = true
+               case <-tl.flush:
                case <-ticker.C:
                }
 
@@ -120,10 +122,10 @@ func (tl *ThrottledLogger) flusher() {
 // underlying Writer.
 func (tl *ThrottledLogger) Close() error {
        select {
-       case <-tl.flush:
+       case <-tl.stopping:
                // already stopped
        default:
-               close(tl.flush)
+               close(tl.stopping)
        }
        <-tl.stopped
        return tl.writer.Close()
@@ -173,8 +175,9 @@ func ReadWriteLines(in io.Reader, writer io.Writer, done chan<- bool) {
 //  at most once per "crunchLogSecondsBetweenEvents" seconds.
 func NewThrottledLogger(writer io.WriteCloser) *ThrottledLogger {
        tl := &ThrottledLogger{}
-       tl.flush = make(chan struct{}, 1)
+       tl.flush = make(chan struct{})
        tl.stopped = make(chan struct{})
+       tl.stopping = make(chan struct{})
        tl.writer = writer
        tl.Logger = log.New(tl, "", 0)
        tl.Timestamper = RFC3339Timestamp