7 files changed, 79 insertions, 13 deletions
diff --git a/vendor/github.com/google/gops/agent/agent.go b/vendor/github.com/google/gops/agent/agent.go
index 59a03cf5..441814c9 100644
--- a/vendor/github.com/google/gops/agent/agent.go
+++ b/vendor/github.com/google/gops/agent/agent.go
@@ -8,6 +8,7 @@ package agent
 
 import (
 	"bufio"
+	"context"
 	"encoding/binary"
 	"fmt"
 	"io"
@@ -55,6 +56,13 @@ type Options struct {
 	// can call Close before shutting down.
 	// Optional.
 	ShutdownCleanup bool
+
+	// ReuseSocketAddrAndPort determines whether the SO_REUSEADDR and
+	// SO_REUSEADDR socket options should be set on the listening socket of
+	// the agent. This option is only effective on unix-like OSes and if
+	// Addr is set to a fixed host:port.
+	// Optional.
+	ReuseSocketAddrAndPort bool
 }
 
 // Listen starts the gops agent on a host process. Once agent started, users
@@ -96,11 +104,14 @@ func Listen(opts Options) error {
 	if addr == "" {
 		addr = defaultAddr
 	}
-	ln, err := net.Listen("tcp", addr)
+	var lc net.ListenConfig
+	if opts.ReuseSocketAddrAndPort {
+		lc.Control = setsockoptReuseAddrAndPort
+	}
+	listener, err = lc.Listen(context.Background(), "tcp", addr)
 	if err != nil {
 		return err
 	}
-	listener = ln
 	port := listener.Addr().(*net.TCPAddr).Port
 	portfile = fmt.Sprintf("%s/%d", gopsdir, os.Getpid())
 	err = ioutil.WriteFile(portfile, []byte(strconv.Itoa(port)), os.ModePerm)
diff --git a/vendor/github.com/google/gops/agent/sockopt_unix.go b/vendor/github.com/google/gops/agent/sockopt_unix.go
new file mode 100644
index 00000000..7edaf209
--- /dev/null
+++ b/vendor/github.com/google/gops/agent/sockopt_unix.go
@@ -0,0 +1,36 @@
+// Copyright 2020 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build !js,!plan9,!windows
+
+package agent
+
+import (
+	"syscall"
+
+	"golang.org/x/sys/unix"
+)
+
+// setsockoptReuseAddrAndPort sets the SO_REUSEADDR and SO_REUSEPORT socket
+// options on c's underlying socket in order to increase the chance to re-bind()
+// to the same address and port upon agent restart.
+func setsockoptReuseAddrAndPort(network, address string, c syscall.RawConn) error {
+	var soerr error
+	if err := c.Control(func(su uintptr) {
+		sock := int(su)
+		// Allow reuse of recently-used addresses. This socket option is
+		// set by default on listeners in Go's net package, see
+		// net.setDefaultSockopts.
+		soerr = unix.SetsockoptInt(sock, unix.SOL_SOCKET, unix.SO_REUSEADDR, 1)
+		if soerr != nil {
+			return
+		}
+		// Allow reuse of recently-used ports. This gives the agent a
+		// better chance to re-bind upon restarts.
+		soerr = unix.SetsockoptInt(sock, unix.SOL_SOCKET, unix.SO_REUSEPORT, 1)
+	}); err != nil {
+		return err
+	}
+	return soerr
+}
diff --git a/vendor/github.com/google/gops/agent/sockopt_unsupported.go b/vendor/github.com/google/gops/agent/sockopt_unsupported.go
new file mode 100644
index 00000000..df3223bd
--- /dev/null
+++ b/vendor/github.com/google/gops/agent/sockopt_unsupported.go
@@ -0,0 +1,13 @@
+// Copyright 2020 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build js,wasm plan9 windows
+
+package agent
+
+import "syscall"
+
+func setsockoptReuseAddrAndPort(network, address string, c syscall.RawConn) error {
+	return nil
+}
diff --git a/vendor/github.com/google/uuid/README.md b/vendor/github.com/google/uuid/README.md
index 9d92c11f..f765a46f 100644
--- a/vendor/github.com/google/uuid/README.md
+++ b/vendor/github.com/google/uuid/README.md
@@ -16,4 +16,4 @@ change is the ability to represent an invalid UUID (vs a NIL UUID).
 
 Full `go doc` style documentation for the package can be viewed online without
 installing this package by using the GoDoc site here: 
-http://godoc.org/github.com/google/uuid
+http://pkg.go.dev/github.com/google/uuid
diff --git a/vendor/github.com/google/uuid/marshal.go b/vendor/github.com/google/uuid/marshal.go
index 7f9e0c6c..14bd3407 100644
--- a/vendor/github.com/google/uuid/marshal.go
+++ b/vendor/github.com/google/uuid/marshal.go
@@ -16,10 +16,11 @@ func (uuid UUID) MarshalText() ([]byte, error) {
 // UnmarshalText implements encoding.TextUnmarshaler.
 func (uuid *UUID) UnmarshalText(data []byte) error {
 	id, err := ParseBytes(data)
-	if err == nil {
-		*uuid = id
+	if err != nil {
+		return err
 	}
-	return err
+	*uuid = id
+	return nil
 }
 
 // MarshalBinary implements encoding.BinaryMarshaler.
diff --git a/vendor/github.com/google/uuid/version1.go b/vendor/github.com/google/uuid/version1.go
index 199a1ac6..46310962 100644
--- a/vendor/github.com/google/uuid/version1.go
+++ b/vendor/github.com/google/uuid/version1.go
@@ -17,12 +17,6 @@ import (
 //
 // In most cases, New should be used.
 func NewUUID() (UUID, error) {
-	nodeMu.Lock()
-	if nodeID == zeroID {
-		setNodeInterface("")
-	}
-	nodeMu.Unlock()
-
 	var uuid UUID
 	now, seq, err := GetTime()
 	if err != nil {
@@ -38,7 +32,13 @@ func NewUUID() (UUID, error) {
 	binary.BigEndian.PutUint16(uuid[4:], timeMid)
 	binary.BigEndian.PutUint16(uuid[6:], timeHi)
 	binary.BigEndian.PutUint16(uuid[8:], seq)
+
+	nodeMu.Lock()
+	if nodeID == zeroID {
+		setNodeInterface("")
+	}
 	copy(uuid[10:], nodeID[:])
+	nodeMu.Unlock()
 
 	return uuid, nil
 }
diff --git a/vendor/github.com/google/uuid/version4.go b/vendor/github.com/google/uuid/version4.go
index 84af91c9..c110465d 100644
--- a/vendor/github.com/google/uuid/version4.go
+++ b/vendor/github.com/google/uuid/version4.go
@@ -27,8 +27,13 @@ func New() UUID {
 //  equivalent to the odds of creating a few tens of trillions of UUIDs in a
 //  year and having one duplicate.
 func NewRandom() (UUID, error) {
+	return NewRandomFromReader(rander)
+}
+
+// NewRandomFromReader returns a UUID based on bytes read from a given io.Reader.
+func NewRandomFromReader(r io.Reader) (UUID, error) {
 	var uuid UUID
-	_, err := io.ReadFull(rander, uuid[:])
+	_, err := io.ReadFull(r, uuid[:])
 	if err != nil {
 		return Nil, err
 	}