vendor: golang.org/x/sync v0.1.0

The golang.org/x/ projects are now doing tagged releases.

full diff: https://github.com/golang/sync/compare/036812b2e83c...v0.1.0

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
(cherry picked from commit 4965f19626)
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>

vendor.mod

@@ -82,7 +82,7 @@ require (
 	github.com/vishvananda/netns v0.0.0-20210104183010-2eb08e3e575f
 	go.etcd.io/bbolt v1.3.6
 	golang.org/x/net v0.0.0-20220906165146-f3363e06e74c
-	golang.org/x/sync v0.0.0-20210220032951-036812b2e83c
+	golang.org/x/sync v0.1.0
 	golang.org/x/sys v0.1.0
 	golang.org/x/time v0.0.0-20211116232009-f0f3c7e86c11
 	google.golang.org/genproto v0.0.0-20220502173005-c8bf987b8c21

vendor.sum

@@ -1307,8 +1307,9 @@ golang.org/x/sync v0.0.0-20200317015054-43a5402ce75a/go.mod h1:RxMgew5VJxzue5/jJ
 golang.org/x/sync v0.0.0-20200625203802-6e8e738ad208/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sync v0.0.0-20201020160332-67f06af15bc9/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sync v0.0.0-20201207232520-09787c993a3a/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
-golang.org/x/sync v0.0.0-20210220032951-036812b2e83c h1:5KslGYwFpkhGh+Q16bwMP3cOontH8FOep7tGV86Y7SQ=
 golang.org/x/sync v0.0.0-20210220032951-036812b2e83c/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
+golang.org/x/sync v0.1.0 h1:wsuoTGHzEhffawBOhz5CYhcrV4IdKZbEyZjBMuTp12o=
+golang.org/x/sync v0.1.0/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sys v0.0.0-20180823144017-11551d06cbcc/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
 golang.org/x/sys v0.0.0-20180830151530-49385e6e1522/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
 golang.org/x/sys v0.0.0-20180905080454-ebe1bf3edb33/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=

vendor/golang.org/x/sync/AUTHORS

@@ -1,3 +0,0 @@
-# This source code refers to The Go Authors for copyright purposes.
-# The master list of authors is in the main Go distribution,
-# visible at http://tip.golang.org/AUTHORS.

vendor/golang.org/x/sync/CONTRIBUTORS

@@ -1,3 +0,0 @@
-# This source code was written by the Go contributors.
-# The master list of contributors is in the main Go distribution,
-# visible at http://tip.golang.org/CONTRIBUTORS.

vendor/golang.org/x/sync/errgroup/errgroup.go

@@ -8,22 +8,35 @@ package errgroup
 
 import (
 	"context"
+	"fmt"
 	"sync"
 )
 
+type token struct{}
+
 // A Group is a collection of goroutines working on subtasks that are part of
 // the same overall task.
 //
-// A zero Group is valid and does not cancel on error.
+// A zero Group is valid, has no limit on the number of active goroutines,
+// and does not cancel on error.
 type Group struct {
 	cancel func()
 
 	wg sync.WaitGroup
 
+	sem chan token
+
 	errOnce sync.Once
 	err     error
 }
 
+func (g *Group) done() {
+	if g.sem != nil {
+		<-g.sem
+	}
+	g.wg.Done()
+}
+
 // WithContext returns a new Group and an associated Context derived from ctx.
 //
 // The derived Context is canceled the first time a function passed to Go
@@ -45,14 +58,19 @@ func (g *Group) Wait() error {
 }
 
 // Go calls the given function in a new goroutine.
+// It blocks until the new goroutine can be added without the number of
+// active goroutines in the group exceeding the configured limit.
 //
-// The first call to return a non-nil error cancels the group; its error will be
-// returned by Wait.
+// The first call to return a non-nil error cancels the group's context, if the
+// group was created by calling WithContext. The error will be returned by Wait.
 func (g *Group) Go(f func() error) {
-	g.wg.Add(1)
+	if g.sem != nil {
+		g.sem <- token{}
+	}
 
+	g.wg.Add(1)
 	go func() {
-		defer g.wg.Done()
+		defer g.done()
 
 		if err := f(); err != nil {
 			g.errOnce.Do(func() {
@@ -64,3 +82,51 @@ func (g *Group) Go(f func() error) {
 		}
 	}()
 }
+
+// TryGo calls the given function in a new goroutine only if the number of
+// active goroutines in the group is currently below the configured limit.
+//
+// The return value reports whether the goroutine was started.
+func (g *Group) TryGo(f func() error) bool {
+	if g.sem != nil {
+		select {
+		case g.sem <- token{}:
+			// Note: this allows barging iff channels in general allow barging.
+		default:
+			return false
+		}
+	}
+
+	g.wg.Add(1)
+	go func() {
+		defer g.done()
+
+		if err := f(); err != nil {
+			g.errOnce.Do(func() {
+				g.err = err
+				if g.cancel != nil {
+					g.cancel()
+				}
+			})
+		}
+	}()
+	return true
+}
+
+// SetLimit limits the number of active goroutines in this group to at most n.
+// A negative value indicates no limit.
+//
+// Any subsequent call to the Go method will block until it can add an active
+// goroutine without exceeding the configured limit.
+//
+// The limit must not be modified while any goroutines in the group are active.
+func (g *Group) SetLimit(n int) {
+	if n < 0 {
+		g.sem = nil
+		return
+	}
+	if len(g.sem) != 0 {
+		panic(fmt.Errorf("errgroup: modify limit while %v goroutines in the group are still active", len(g.sem)))
+	}
+	g.sem = make(chan token, n)
+}

vendor/golang.org/x/sync/singleflight/singleflight.go

@@ -52,10 +52,6 @@ type call struct {
 	val interface{}
 	err error
 
-	// forgotten indicates whether Forget was called with this call's key
-	// while the call was still in flight.
-	forgotten bool
-
 	// These fields are read and written with the singleflight
 	// mutex held before the WaitGroup is done, and are read but
 	// not written after the WaitGroup is done.
@@ -148,10 +144,10 @@ func (g *Group) doCall(c *call, key string, fn func() (interface{}, error)) {
 			c.err = errGoexit
 		}
 
-		c.wg.Done()
 		g.mu.Lock()
 		defer g.mu.Unlock()
-		if !c.forgotten {
+		c.wg.Done()
+		if g.m[key] == c {
 			delete(g.m, key)
 		}
 
@@ -204,9 +200,6 @@ func (g *Group) doCall(c *call, key string, fn func() (interface{}, error)) {
 // an earlier call to complete.
 func (g *Group) Forget(key string) {
 	g.mu.Lock()
-	if c, ok := g.m[key]; ok {
-		c.forgotten = true
-	}
 	delete(g.m, key)
 	g.mu.Unlock()
 }

vendor/modules.txt

@@ -948,7 +948,7 @@ golang.org/x/oauth2/google/internal/externalaccount
 golang.org/x/oauth2/internal
 golang.org/x/oauth2/jws
 golang.org/x/oauth2/jwt
-# golang.org/x/sync v0.0.0-20210220032951-036812b2e83c
+# golang.org/x/sync v0.1.0
 ## explicit
 golang.org/x/sync/errgroup
 golang.org/x/sync/semaphore