X-Git-Url: https://git.arvados.org/lightning.git/blobdiff_plain/00b2acd54dd1aa412f6f2bddc24b1bbb31c7ae3f..b9a352b3c94fbefd189bf72694ef52fe561f0515:/throttle.go

diff --git a/throttle.go b/throttle.go
index da338f62f5..8b087eeae2 100644
--- a/throttle.go
+++ b/throttle.go
@@ -1,3 +1,7 @@
+// Copyright (C) The Lightning Authors. All rights reserved.
+//
+// SPDX-License-Identifier: AGPL-3.0
+
 package lightning
 
 import (
@@ -15,7 +19,12 @@ type throttle struct {
 }
 
 func (t *throttle) Acquire() {
-	t.setupOnce.Do(func() { t.ch = make(chan bool, t.Max) })
+	t.setupOnce.Do(func() {
+		if t.Max < 1 {
+			panic("throttle.Max < 1")
+		}
+		t.ch = make(chan bool, t.Max)
+	})
 	t.wg.Add(1)
 	t.ch <- true
 }
@@ -40,3 +49,16 @@ func (t *throttle) Wait() error {
 	t.wg.Wait()
 	return t.Err()
 }
+
+func (t *throttle) Go(f func() error) error {
+	t.Acquire()
+	if t.Err() != nil {
+		t.Release()
+		return t.Err()
+	}
+	go func() {
+		t.Report(f())
+		t.Release()
+	}()
+	return nil
+}