Bump dependency github.com/coreos/go-systemd@v19 (95778df)

go.mod

@@ -39,7 +39,7 @@ require (
 	github.com/containernetworking/cni v0.7.1
 	github.com/coredns/corefile-migration v1.0.2
 	github.com/coreos/etcd v3.3.15+incompatible
-	github.com/coreos/go-systemd v0.0.0-20180511133405-39ca1b05acc7
+	github.com/coreos/go-systemd v0.0.0-20190321100706-95778dfbb74e
 	github.com/coreos/pkg v0.0.0-20180108230652-97fdf19511ea
 	github.com/coreos/rkt v1.30.0 // indirect
 	github.com/cpuguy83/go-md2man v1.0.10
@@ -231,7 +231,7 @@ replace (
 	github.com/coreos/go-etcd => github.com/coreos/go-etcd v2.0.0+incompatible
 	github.com/coreos/go-oidc => github.com/coreos/go-oidc v2.1.0+incompatible
 	github.com/coreos/go-semver => github.com/coreos/go-semver v0.3.0
-	github.com/coreos/go-systemd => github.com/coreos/go-systemd v0.0.0-20180511133405-39ca1b05acc7
+	github.com/coreos/go-systemd => github.com/coreos/go-systemd v0.0.0-20190321100706-95778dfbb74e
 	github.com/coreos/pkg => github.com/coreos/pkg v0.0.0-20180108230652-97fdf19511ea
 	github.com/coreos/rkt => github.com/coreos/rkt v1.30.0
 	github.com/cpuguy83/go-md2man => github.com/cpuguy83/go-md2man v1.0.10

go.sum

@@ -104,8 +104,8 @@ github.com/coreos/go-oidc v2.1.0+incompatible h1:sdJrfw8akMnCuUlaZU3tE/uYXFgfqom
 github.com/coreos/go-oidc v2.1.0+incompatible/go.mod h1:CgnwVTmzoESiwO9qyAFEMiHoZ1nMCKZlZ9V6mm3/LKc=
 github.com/coreos/go-semver v0.3.0 h1:wkHLiw0WNATZnSG7epLsujiMCgPAc9xhjJ4tgnAxmfM=
 github.com/coreos/go-semver v0.3.0/go.mod h1:nnelYz7RCh+5ahJtPPxZlU+153eP4D4r3EedlOD2RNk=
-github.com/coreos/go-systemd v0.0.0-20180511133405-39ca1b05acc7 h1:u9SHYsPQNyt5tgDm3YN7+9dYrpK96E5wFilTFWIDZOM=
+github.com/coreos/go-systemd v0.0.0-20190321100706-95778dfbb74e h1:Wf6HqHfScWJN9/ZjdUKyjop4mf3Qdd+1TvvltAvM3m8=
-github.com/coreos/go-systemd v0.0.0-20180511133405-39ca1b05acc7/go.mod h1:F5haX7vjVVG0kc13fIWeqUViNPyEJxv/OmvnBo0Yme4=
+github.com/coreos/go-systemd v0.0.0-20190321100706-95778dfbb74e/go.mod h1:F5haX7vjVVG0kc13fIWeqUViNPyEJxv/OmvnBo0Yme4=
 github.com/coreos/pkg v0.0.0-20180108230652-97fdf19511ea h1:n2Ltr3SrfQlf/9nOna1DoGKxLx3qTSI8Ttl6Xrqp6mw=
 github.com/coreos/pkg v0.0.0-20180108230652-97fdf19511ea/go.mod h1:E3G3o1h8I7cfcXa63jLwjI0eiQQMgzzUDFVpN/nH/eA=
 github.com/coreos/rkt v1.30.0 h1:Kkt6sYeEGKxA3Y7SCrY+nHoXkWed6Jr2BBY42GqMymM=

staging/src/k8s.io/apiextensions-apiserver/go.sum

@@ -46,8 +46,8 @@ github.com/coreos/go-oidc v2.1.0+incompatible/go.mod h1:CgnwVTmzoESiwO9qyAFEMiHo
 github.com/coreos/go-semver v0.2.0/go.mod h1:nnelYz7RCh+5ahJtPPxZlU+153eP4D4r3EedlOD2RNk=
 github.com/coreos/go-semver v0.3.0 h1:wkHLiw0WNATZnSG7epLsujiMCgPAc9xhjJ4tgnAxmfM=
 github.com/coreos/go-semver v0.3.0/go.mod h1:nnelYz7RCh+5ahJtPPxZlU+153eP4D4r3EedlOD2RNk=
-github.com/coreos/go-systemd v0.0.0-20180511133405-39ca1b05acc7 h1:u9SHYsPQNyt5tgDm3YN7+9dYrpK96E5wFilTFWIDZOM=
+github.com/coreos/go-systemd v0.0.0-20190321100706-95778dfbb74e h1:Wf6HqHfScWJN9/ZjdUKyjop4mf3Qdd+1TvvltAvM3m8=
-github.com/coreos/go-systemd v0.0.0-20180511133405-39ca1b05acc7/go.mod h1:F5haX7vjVVG0kc13fIWeqUViNPyEJxv/OmvnBo0Yme4=
+github.com/coreos/go-systemd v0.0.0-20190321100706-95778dfbb74e/go.mod h1:F5haX7vjVVG0kc13fIWeqUViNPyEJxv/OmvnBo0Yme4=
 github.com/coreos/pkg v0.0.0-20180108230652-97fdf19511ea h1:n2Ltr3SrfQlf/9nOna1DoGKxLx3qTSI8Ttl6Xrqp6mw=
 github.com/coreos/pkg v0.0.0-20180108230652-97fdf19511ea/go.mod h1:E3G3o1h8I7cfcXa63jLwjI0eiQQMgzzUDFVpN/nH/eA=
 github.com/cpuguy83/go-md2man v1.0.10/go.mod h1:SmD6nW6nTyfqj6ABTjUi3V3JVMnlJmwcJI5acqYI6dE=

staging/src/k8s.io/apiserver/go.mod

@@ -10,7 +10,7 @@ require (
 	github.com/coreos/etcd v3.3.15+incompatible
 	github.com/coreos/go-oidc v2.1.0+incompatible
 	github.com/coreos/go-semver v0.3.0 // indirect
-	github.com/coreos/go-systemd v0.0.0-20180511133405-39ca1b05acc7
+	github.com/coreos/go-systemd v0.0.0-20190321100706-95778dfbb74e
 	github.com/coreos/pkg v0.0.0-20180108230652-97fdf19511ea
 	github.com/docker/docker v0.7.3-0.20190327010347-be7ac8be2ae0
 	github.com/emicklei/go-restful v2.9.5+incompatible

staging/src/k8s.io/apiserver/go.sum

@@ -37,8 +37,8 @@ github.com/coreos/go-oidc v2.1.0+incompatible h1:sdJrfw8akMnCuUlaZU3tE/uYXFgfqom
 github.com/coreos/go-oidc v2.1.0+incompatible/go.mod h1:CgnwVTmzoESiwO9qyAFEMiHoZ1nMCKZlZ9V6mm3/LKc=
 github.com/coreos/go-semver v0.3.0 h1:wkHLiw0WNATZnSG7epLsujiMCgPAc9xhjJ4tgnAxmfM=
 github.com/coreos/go-semver v0.3.0/go.mod h1:nnelYz7RCh+5ahJtPPxZlU+153eP4D4r3EedlOD2RNk=
-github.com/coreos/go-systemd v0.0.0-20180511133405-39ca1b05acc7 h1:u9SHYsPQNyt5tgDm3YN7+9dYrpK96E5wFilTFWIDZOM=
+github.com/coreos/go-systemd v0.0.0-20190321100706-95778dfbb74e h1:Wf6HqHfScWJN9/ZjdUKyjop4mf3Qdd+1TvvltAvM3m8=
-github.com/coreos/go-systemd v0.0.0-20180511133405-39ca1b05acc7/go.mod h1:F5haX7vjVVG0kc13fIWeqUViNPyEJxv/OmvnBo0Yme4=
+github.com/coreos/go-systemd v0.0.0-20190321100706-95778dfbb74e/go.mod h1:F5haX7vjVVG0kc13fIWeqUViNPyEJxv/OmvnBo0Yme4=
 github.com/coreos/pkg v0.0.0-20180108230652-97fdf19511ea h1:n2Ltr3SrfQlf/9nOna1DoGKxLx3qTSI8Ttl6Xrqp6mw=
 github.com/coreos/pkg v0.0.0-20180108230652-97fdf19511ea/go.mod h1:E3G3o1h8I7cfcXa63jLwjI0eiQQMgzzUDFVpN/nH/eA=
 github.com/davecgh/go-spew v0.0.0-20151105211317-5215b55f46b2/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=

staging/src/k8s.io/kube-aggregator/go.sum

@@ -40,8 +40,8 @@ github.com/coreos/go-oidc v2.1.0+incompatible/go.mod h1:CgnwVTmzoESiwO9qyAFEMiHo
 github.com/coreos/go-semver v0.2.0/go.mod h1:nnelYz7RCh+5ahJtPPxZlU+153eP4D4r3EedlOD2RNk=
 github.com/coreos/go-semver v0.3.0 h1:wkHLiw0WNATZnSG7epLsujiMCgPAc9xhjJ4tgnAxmfM=
 github.com/coreos/go-semver v0.3.0/go.mod h1:nnelYz7RCh+5ahJtPPxZlU+153eP4D4r3EedlOD2RNk=
-github.com/coreos/go-systemd v0.0.0-20180511133405-39ca1b05acc7 h1:u9SHYsPQNyt5tgDm3YN7+9dYrpK96E5wFilTFWIDZOM=
+github.com/coreos/go-systemd v0.0.0-20190321100706-95778dfbb74e h1:Wf6HqHfScWJN9/ZjdUKyjop4mf3Qdd+1TvvltAvM3m8=
-github.com/coreos/go-systemd v0.0.0-20180511133405-39ca1b05acc7/go.mod h1:F5haX7vjVVG0kc13fIWeqUViNPyEJxv/OmvnBo0Yme4=
+github.com/coreos/go-systemd v0.0.0-20190321100706-95778dfbb74e/go.mod h1:F5haX7vjVVG0kc13fIWeqUViNPyEJxv/OmvnBo0Yme4=
 github.com/coreos/pkg v0.0.0-20180108230652-97fdf19511ea h1:n2Ltr3SrfQlf/9nOna1DoGKxLx3qTSI8Ttl6Xrqp6mw=
 github.com/coreos/pkg v0.0.0-20180108230652-97fdf19511ea/go.mod h1:E3G3o1h8I7cfcXa63jLwjI0eiQQMgzzUDFVpN/nH/eA=
 github.com/cpuguy83/go-md2man v1.0.10/go.mod h1:SmD6nW6nTyfqj6ABTjUi3V3JVMnlJmwcJI5acqYI6dE=

staging/src/k8s.io/legacy-cloud-providers/go.sum

@@ -46,7 +46,7 @@ github.com/coreos/bbolt v1.3.1-coreos.6/go.mod h1:iRUV2dpdMOn7Bo10OQBFzIJO9kkE55
 github.com/coreos/etcd v3.3.15+incompatible/go.mod h1:uF7uidLiAD3TWHmW31ZFd/JWoc32PjwdhPthX9715RE=
 github.com/coreos/go-oidc v2.1.0+incompatible/go.mod h1:CgnwVTmzoESiwO9qyAFEMiHoZ1nMCKZlZ9V6mm3/LKc=
 github.com/coreos/go-semver v0.3.0/go.mod h1:nnelYz7RCh+5ahJtPPxZlU+153eP4D4r3EedlOD2RNk=
-github.com/coreos/go-systemd v0.0.0-20180511133405-39ca1b05acc7/go.mod h1:F5haX7vjVVG0kc13fIWeqUViNPyEJxv/OmvnBo0Yme4=
+github.com/coreos/go-systemd v0.0.0-20190321100706-95778dfbb74e/go.mod h1:F5haX7vjVVG0kc13fIWeqUViNPyEJxv/OmvnBo0Yme4=
 github.com/coreos/pkg v0.0.0-20180108230652-97fdf19511ea/go.mod h1:E3G3o1h8I7cfcXa63jLwjI0eiQQMgzzUDFVpN/nH/eA=
 github.com/davecgh/go-spew v0.0.0-20151105211317-5215b55f46b2/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=

staging/src/k8s.io/sample-apiserver/go.sum

@@ -40,8 +40,8 @@ github.com/coreos/go-oidc v2.1.0+incompatible/go.mod h1:CgnwVTmzoESiwO9qyAFEMiHo
 github.com/coreos/go-semver v0.2.0/go.mod h1:nnelYz7RCh+5ahJtPPxZlU+153eP4D4r3EedlOD2RNk=
 github.com/coreos/go-semver v0.3.0 h1:wkHLiw0WNATZnSG7epLsujiMCgPAc9xhjJ4tgnAxmfM=
 github.com/coreos/go-semver v0.3.0/go.mod h1:nnelYz7RCh+5ahJtPPxZlU+153eP4D4r3EedlOD2RNk=
-github.com/coreos/go-systemd v0.0.0-20180511133405-39ca1b05acc7 h1:u9SHYsPQNyt5tgDm3YN7+9dYrpK96E5wFilTFWIDZOM=
+github.com/coreos/go-systemd v0.0.0-20190321100706-95778dfbb74e h1:Wf6HqHfScWJN9/ZjdUKyjop4mf3Qdd+1TvvltAvM3m8=
-github.com/coreos/go-systemd v0.0.0-20180511133405-39ca1b05acc7/go.mod h1:F5haX7vjVVG0kc13fIWeqUViNPyEJxv/OmvnBo0Yme4=
+github.com/coreos/go-systemd v0.0.0-20190321100706-95778dfbb74e/go.mod h1:F5haX7vjVVG0kc13fIWeqUViNPyEJxv/OmvnBo0Yme4=
 github.com/coreos/pkg v0.0.0-20180108230652-97fdf19511ea h1:n2Ltr3SrfQlf/9nOna1DoGKxLx3qTSI8Ttl6Xrqp6mw=
 github.com/coreos/pkg v0.0.0-20180108230652-97fdf19511ea/go.mod h1:E3G3o1h8I7cfcXa63jLwjI0eiQQMgzzUDFVpN/nH/eA=
 github.com/cpuguy83/go-md2man v1.0.10/go.mod h1:SmD6nW6nTyfqj6ABTjUi3V3JVMnlJmwcJI5acqYI6dE=

vendor/github.com/coreos/go-systemd/dbus/dbus.go

@@ -143,7 +143,7 @@ func NewUserConnection() (*Conn, error) {
 func NewSystemdConnection() (*Conn, error) {
 	return NewConnection(func() (*dbus.Conn, error) {
 		// We skip Hello when talking directly to systemd.
-		return dbusAuthConnection(func() (*dbus.Conn, error) {
+		return dbusAuthConnection(func(opts ...dbus.ConnOption) (*dbus.Conn, error) {
 			return dbus.Dial("unix:path=/run/systemd/private")
 		})
 	})
@@ -201,7 +201,7 @@ func (c *Conn) GetManagerProperty(prop string) (string, error) {
 	return variant.String(), nil
 }
 
-func dbusAuthConnection(createBus func() (*dbus.Conn, error)) (*dbus.Conn, error) {
+func dbusAuthConnection(createBus func(opts ...dbus.ConnOption) (*dbus.Conn, error)) (*dbus.Conn, error) {
 	conn, err := createBus()
 	if err != nil {
 		return nil, err
@@ -221,7 +221,7 @@ func dbusAuthConnection(createBus func() (*dbus.Conn, error)) (*dbus.Conn, error
 	return conn, nil
 }
 
-func dbusAuthHelloConnection(createBus func() (*dbus.Conn, error)) (*dbus.Conn, error) {
+func dbusAuthHelloConnection(createBus func(opts ...dbus.ConnOption) (*dbus.Conn, error)) (*dbus.Conn, error) {
 	conn, err := dbusAuthConnection(createBus)
 	if err != nil {
 		return nil, err

vendor/github.com/coreos/go-systemd/dbus/methods.go

@@ -117,13 +117,13 @@ func (c *Conn) TryRestartUnit(name string, mode string, ch chan<- string) (int,
 	return c.startJob(ch, "org.freedesktop.systemd1.Manager.TryRestartUnit", name, mode)
 }
 
-// ReloadOrRestart attempts a reload if the unit supports it and use a restart
+// ReloadOrRestartUnit attempts a reload if the unit supports it and use a restart
 // otherwise.
 func (c *Conn) ReloadOrRestartUnit(name string, mode string, ch chan<- string) (int, error) {
 	return c.startJob(ch, "org.freedesktop.systemd1.Manager.ReloadOrRestartUnit", name, mode)
 }
 
-// ReloadOrTryRestart attempts a reload if the unit supports it and use a "Try"
+// ReloadOrTryRestartUnit attempts a reload if the unit supports it and use a "Try"
 // flavored restart otherwise.
 func (c *Conn) ReloadOrTryRestartUnit(name string, mode string, ch chan<- string) (int, error) {
 	return c.startJob(ch, "org.freedesktop.systemd1.Manager.ReloadOrTryRestartUnit", name, mode)
@@ -192,7 +192,7 @@ func (c *Conn) GetUnitProperties(unit string) (map[string]interface{}, error) {
 	return c.getProperties(path, "org.freedesktop.systemd1.Unit")
 }
 
-// GetUnitProperties takes the (escaped) unit path and returns all of its dbus object properties.
+// GetUnitPathProperties takes the (escaped) unit path and returns all of its dbus object properties.
 func (c *Conn) GetUnitPathProperties(path dbus.ObjectPath) (map[string]interface{}, error) {
 	return c.getProperties(path, "org.freedesktop.systemd1.Unit")
 }
@@ -291,6 +291,8 @@ func (c *Conn) listUnitsInternal(f storeFunc) ([]UnitStatus, error) {
 // ListUnits returns an array with all currently loaded units. Note that
 // units may be known by multiple names at the same time, and hence there might
 // be more unit names loaded than actual units behind them.
+// Also note that a unit is only loaded if it is active and/or enabled.
+// Units that are both disabled and inactive will thus not be returned.
 func (c *Conn) ListUnits() ([]UnitStatus, error) {
 	return c.listUnitsInternal(c.sysobj.Call("org.freedesktop.systemd1.Manager.ListUnits", 0).Store)
 }

vendor/github.com/coreos/go-systemd/dbus/subscription.go

@@ -94,7 +94,7 @@ func (c *Conn) dispatch() {
 	}()
 }
 
-// Returns two unbuffered channels which will receive all changed units every
+// SubscribeUnits returns two unbuffered channels which will receive all changed units every
 // interval.  Deleted units are sent as nil.
 func (c *Conn) SubscribeUnits(interval time.Duration) (<-chan map[string]*UnitStatus, <-chan error) {
 	return c.SubscribeUnitsCustom(interval, 0, func(u1, u2 *UnitStatus) bool { return *u1 != *u2 }, nil)

vendor/github.com/coreos/go-systemd/journal/journal.go

@@ -33,7 +33,10 @@ import (
 	"os"
 	"strconv"
 	"strings"
+	"sync"
+	"sync/atomic"
 	"syscall"
+	"unsafe"
 )
 
 // Priority of a journal message
@@ -50,19 +53,35 @@ const (
 	PriDebug
 )
 
-var conn net.Conn
+var (
+	// This can be overridden at build-time:
+	// https://github.com/golang/go/wiki/GcToolchainTricks#including-build-information-in-the-executable
+	journalSocket = "/run/systemd/journal/socket"
+
+	// unixConnPtr atomically holds the local unconnected Unix-domain socket.
+	// Concrete safe pointer type: *net.UnixConn
+	unixConnPtr unsafe.Pointer
+	// onceConn ensures that unixConnPtr is initialized exactly once.
+	onceConn sync.Once
+)
 
 func init() {
-	var err error
+	onceConn.Do(initConn)
-	conn, err = net.Dial("unixgram", "/run/systemd/journal/socket")
-	if err != nil {
-		conn = nil
-	}
 }
 
-// Enabled returns true if the local systemd journal is available for logging
+// Enabled checks whether the local systemd journal is available for logging.
 func Enabled() bool {
-	return conn != nil
+	onceConn.Do(initConn)
+
+	if (*net.UnixConn)(atomic.LoadPointer(&unixConnPtr)) == nil {
+		return false
+	}
+
+	if _, err := net.Dial("unixgram", journalSocket); err != nil {
+		return false
+	}
+
+	return true
 }
 
 // Send a message to the local systemd journal. vars is a map of journald
@@ -73,8 +92,14 @@ func Enabled() bool {
 // (http://www.freedesktop.org/software/systemd/man/systemd.journal-fields.html)
 // for more details.  vars may be nil.
 func Send(message string, priority Priority, vars map[string]string) error {
+	conn := (*net.UnixConn)(atomic.LoadPointer(&unixConnPtr))
 	if conn == nil {
-		return journalError("could not connect to journald socket")
+		return errors.New("could not initialize socket to journald")
+	}
+
+	socketAddr := &net.UnixAddr{
+		Name: journalSocket,
+		Net:  "unixgram",
 	}
 
 	data := new(bytes.Buffer)
@@ -84,32 +109,30 @@ func Send(message string, priority Priority, vars map[string]string) error {
 		appendVariable(data, k, v)
 	}
 
-	_, err := io.Copy(conn, data)
+	_, _, err := conn.WriteMsgUnix(data.Bytes(), nil, socketAddr)
-	if err != nil && isSocketSpaceError(err) {
+	if err == nil {
+		return nil
+	}
+	if !isSocketSpaceError(err) {
+		return err
+	}
+
+	// Large log entry, send it via tempfile and ancillary-fd.
 	file, err := tempFd()
 	if err != nil {
-			return journalError(err.Error())
+		return err
 	}
 	defer file.Close()
 	_, err = io.Copy(file, data)
 	if err != nil {
-			return journalError(err.Error())
+		return err
 	}
-
 	rights := syscall.UnixRights(int(file.Fd()))
-
+	_, _, err = conn.WriteMsgUnix([]byte{}, rights, socketAddr)
-		/* this connection should always be a UnixConn, but better safe than sorry */
-		unixConn, ok := conn.(*net.UnixConn)
-		if !ok {
-			return journalError("can't send file through non-Unix connection")
-		}
-		_, _, err = unixConn.WriteMsgUnix([]byte{}, rights, nil)
 	if err != nil {
-			return journalError(err.Error())
+		return err
-		}
-	} else if err != nil {
-		return journalError(err.Error())
 	}
+
 	return nil
 }
 
@@ -119,8 +142,8 @@ func Print(priority Priority, format string, a ...interface{}) error {
 }
 
 func appendVariable(w io.Writer, name, value string) {
-	if !validVarName(name) {
+	if err := validVarName(name); err != nil {
-		journalError("variable name contains invalid character, ignoring")
+		fmt.Fprintf(os.Stderr, "variable name %s contains invalid character, ignoring\n", name)
 	}
 	if strings.ContainsRune(value, '\n') {
 		/* When the value contains a newline, we write:
@@ -137,32 +160,42 @@ func appendVariable(w io.Writer, name, value string) {
 	}
 }
 
-func validVarName(name string) bool {
+// validVarName validates a variable name to make sure journald will accept it.
-	/* The variable name must be in uppercase and consist only of characters,
+// The variable name must be in uppercase and consist only of characters,
-	 * numbers and underscores, and may not begin with an underscore. (from the docs)
+// numbers and underscores, and may not begin with an underscore:
-	 */
+// https://www.freedesktop.org/software/systemd/man/sd_journal_print.html
-
+func validVarName(name string) error {
-	valid := name[0] != '_'
+	if name == "" {
-	for _, c := range name {
+		return errors.New("Empty variable name")
-		valid = valid && ('A' <= c && c <= 'Z') || ('0' <= c && c <= '9') || c == '_'
+	} else if name[0] == '_' {
+		return errors.New("Variable name begins with an underscore")
 	}
-	return valid
+
+	for _, c := range name {
+		if !(('A' <= c && c <= 'Z') || ('0' <= c && c <= '9') || c == '_') {
+			return errors.New("Variable name contains invalid characters")
+		}
+	}
+	return nil
 }
 
+// isSocketSpaceError checks whether the error is signaling
+// an "overlarge message" condition.
 func isSocketSpaceError(err error) bool {
 	opErr, ok := err.(*net.OpError)
-	if !ok {
+	if !ok || opErr == nil {
 		return false
 	}
 
-	sysErr, ok := opErr.Err.(syscall.Errno)
+	sysErr, ok := opErr.Err.(*os.SyscallError)
-	if !ok {
+	if !ok || sysErr == nil {
 		return false
 	}
 
-	return sysErr == syscall.EMSGSIZE || sysErr == syscall.ENOBUFS
+	return sysErr.Err == syscall.EMSGSIZE || sysErr.Err == syscall.ENOBUFS
 }
 
+// tempFd creates a temporary, unlinked file under `/dev/shm`.
 func tempFd() (*os.File, error) {
 	file, err := ioutil.TempFile("/dev/shm/", "journal.XXXXX")
 	if err != nil {
@@ -175,8 +208,18 @@ func tempFd() (*os.File, error) {
 	return file, nil
 }
 
-func journalError(s string) error {
+// initConn initializes the global `unixConnPtr` socket.
-	s = "journal error: " + s
+// It is meant to be called exactly once, at program startup.
-	fmt.Fprintln(os.Stderr, s)
+func initConn() {
-	return errors.New(s)
+	autobind, err := net.ResolveUnixAddr("unixgram", "")
+	if err != nil {
+		return
+	}
+
+	sock, err := net.ListenUnixgram("unixgram", autobind)
+	if err != nil {
+		return
+	}
+
+	atomic.StorePointer(&unixConnPtr, unsafe.Pointer(sock))
 }

vendor/modules.txt

@@ -278,7 +278,7 @@ github.com/coreos/etcd/wal/walpb
 github.com/coreos/go-oidc
 # github.com/coreos/go-semver v0.3.0 => github.com/coreos/go-semver v0.3.0
 github.com/coreos/go-semver/semver
-# github.com/coreos/go-systemd v0.0.0-20180511133405-39ca1b05acc7 => github.com/coreos/go-systemd v0.0.0-20180511133405-39ca1b05acc7
+# github.com/coreos/go-systemd v0.0.0-20190321100706-95778dfbb74e => github.com/coreos/go-systemd v0.0.0-20190321100706-95778dfbb74e
 github.com/coreos/go-systemd/daemon
 github.com/coreos/go-systemd/dbus
 github.com/coreos/go-systemd/journal