Update dependency go modules for k8s v1.27.0-rc.0

vendor/k8s.io/utils/net/ipfamily.go

@@ -0,0 +1,181 @@
+/*
+Copyright 2018 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package net
+
+import (
+	"fmt"
+	"net"
+)
+
+// IPFamily refers to a specific family if not empty, i.e. "4" or "6".
+type IPFamily string
+
+// Constants for valid IPFamilys:
+const (
+	IPFamilyUnknown IPFamily = ""
+
+	IPv4 IPFamily = "4"
+	IPv6 IPFamily = "6"
+)
+
+// IsDualStackIPs returns true if:
+// - all elements of ips are valid
+// - at least one IP from each family (v4 and v6) is present
+func IsDualStackIPs(ips []net.IP) (bool, error) {
+	v4Found := false
+	v6Found := false
+	for i, ip := range ips {
+		switch IPFamilyOf(ip) {
+		case IPv4:
+			v4Found = true
+		case IPv6:
+			v6Found = true
+		default:
+			return false, fmt.Errorf("invalid IP[%d]: %v", i, ip)
+		}
+	}
+
+	return (v4Found && v6Found), nil
+}
+
+// IsDualStackIPStrings returns true if:
+// - all elements of ips can be parsed as IPs
+// - at least one IP from each family (v4 and v6) is present
+func IsDualStackIPStrings(ips []string) (bool, error) {
+	parsedIPs := make([]net.IP, 0, len(ips))
+	for i, ip := range ips {
+		parsedIP := ParseIPSloppy(ip)
+		if parsedIP == nil {
+			return false, fmt.Errorf("invalid IP[%d]: %v", i, ip)
+		}
+		parsedIPs = append(parsedIPs, parsedIP)
+	}
+	return IsDualStackIPs(parsedIPs)
+}
+
+// IsDualStackCIDRs returns true if:
+// - all elements of cidrs are non-nil
+// - at least one CIDR from each family (v4 and v6) is present
+func IsDualStackCIDRs(cidrs []*net.IPNet) (bool, error) {
+	v4Found := false
+	v6Found := false
+	for i, cidr := range cidrs {
+		switch IPFamilyOfCIDR(cidr) {
+		case IPv4:
+			v4Found = true
+		case IPv6:
+			v6Found = true
+		default:
+			return false, fmt.Errorf("invalid CIDR[%d]: %v", i, cidr)
+		}
+	}
+
+	return (v4Found && v6Found), nil
+}
+
+// IsDualStackCIDRStrings returns if
+// - all elements of cidrs can be parsed as CIDRs
+// - at least one CIDR from each family (v4 and v6) is present
+func IsDualStackCIDRStrings(cidrs []string) (bool, error) {
+	parsedCIDRs, err := ParseCIDRs(cidrs)
+	if err != nil {
+		return false, err
+	}
+	return IsDualStackCIDRs(parsedCIDRs)
+}
+
+// IPFamilyOf returns the IP family of ip, or IPFamilyUnknown if it is invalid.
+func IPFamilyOf(ip net.IP) IPFamily {
+	switch {
+	case ip.To4() != nil:
+		return IPv4
+	case ip.To16() != nil:
+		return IPv6
+	default:
+		return IPFamilyUnknown
+	}
+}
+
+// IPFamilyOfString returns the IP family of ip, or IPFamilyUnknown if ip cannot
+// be parsed as an IP.
+func IPFamilyOfString(ip string) IPFamily {
+	return IPFamilyOf(ParseIPSloppy(ip))
+}
+
+// IPFamilyOfCIDR returns the IP family of cidr.
+func IPFamilyOfCIDR(cidr *net.IPNet) IPFamily {
+	if cidr == nil {
+		return IPFamilyUnknown
+	}
+	return IPFamilyOf(cidr.IP)
+}
+
+// IPFamilyOfCIDRString returns the IP family of cidr.
+func IPFamilyOfCIDRString(cidr string) IPFamily {
+	ip, _, _ := ParseCIDRSloppy(cidr)
+	return IPFamilyOf(ip)
+}
+
+// IsIPv6 returns true if netIP is IPv6 (and false if it is IPv4, nil, or invalid).
+func IsIPv6(netIP net.IP) bool {
+	return IPFamilyOf(netIP) == IPv6
+}
+
+// IsIPv6String returns true if ip contains a single IPv6 address and nothing else. It
+// returns false if ip is an empty string, an IPv4 address, or anything else that is not a
+// single IPv6 address.
+func IsIPv6String(ip string) bool {
+	return IPFamilyOfString(ip) == IPv6
+}
+
+// IsIPv6CIDR returns true if a cidr is a valid IPv6 CIDR. It returns false if cidr is
+// nil or an IPv4 CIDR. Its behavior is not defined if cidr is invalid.
+func IsIPv6CIDR(cidr *net.IPNet) bool {
+	return IPFamilyOfCIDR(cidr) == IPv6
+}
+
+// IsIPv6CIDRString returns true if cidr contains a single IPv6 CIDR and nothing else. It
+// returns false if cidr is an empty string, an IPv4 CIDR, or anything else that is not a
+// single valid IPv6 CIDR.
+func IsIPv6CIDRString(cidr string) bool {
+	return IPFamilyOfCIDRString(cidr) == IPv6
+}
+
+// IsIPv4 returns true if netIP is IPv4 (and false if it is IPv6, nil, or invalid).
+func IsIPv4(netIP net.IP) bool {
+	return IPFamilyOf(netIP) == IPv4
+}
+
+// IsIPv4String returns true if ip contains a single IPv4 address and nothing else. It
+// returns false if ip is an empty string, an IPv6 address, or anything else that is not a
+// single IPv4 address.
+func IsIPv4String(ip string) bool {
+	return IPFamilyOfString(ip) == IPv4
+}
+
+// IsIPv4CIDR returns true if cidr is a valid IPv4 CIDR. It returns false if cidr is nil
+// or an IPv6 CIDR. Its behavior is not defined if cidr is invalid.
+func IsIPv4CIDR(cidr *net.IPNet) bool {
+	return IPFamilyOfCIDR(cidr) == IPv4
+}
+
+// IsIPv4CIDRString returns true if cidr contains a single IPv4 CIDR and nothing else. It
+// returns false if cidr is an empty string, an IPv6 CIDR, or anything else that is not a
+// single valid IPv4 CIDR.
+func IsIPv4CIDRString(cidr string) bool {
+	return IPFamilyOfCIDRString(cidr) == IPv4
+}

vendor/k8s.io/utils/net/net.go

@@ -29,138 +29,16 @@ import (
 // order is maintained
 func ParseCIDRs(cidrsString []string) ([]*net.IPNet, error) {
 	cidrs := make([]*net.IPNet, 0, len(cidrsString))
-	for _, cidrString := range cidrsString {
+	for i, cidrString := range cidrsString {
 		_, cidr, err := ParseCIDRSloppy(cidrString)
 		if err != nil {
-			return nil, fmt.Errorf("failed to parse cidr value:%q with error:%v", cidrString, err)
+			return nil, fmt.Errorf("invalid CIDR[%d]: %v (%v)", i, cidr, err)
 		}
 		cidrs = append(cidrs, cidr)
 	}
 	return cidrs, nil
 }
 
-// IsDualStackIPs returns if a slice of ips is:
-// - all are valid ips
-// - at least one ip from each family (v4 or v6)
-func IsDualStackIPs(ips []net.IP) (bool, error) {
-	v4Found := false
-	v6Found := false
-	for _, ip := range ips {
-		if ip == nil {
-			return false, fmt.Errorf("ip %v is invalid", ip)
-		}
-
-		if v4Found && v6Found {
-			continue
-		}
-
-		if IsIPv6(ip) {
-			v6Found = true
-			continue
-		}
-
-		v4Found = true
-	}
-
-	return (v4Found && v6Found), nil
-}
-
-// IsDualStackIPStrings returns if
-// - all are valid ips
-// - at least one ip from each family (v4 or v6)
-func IsDualStackIPStrings(ips []string) (bool, error) {
-	parsedIPs := make([]net.IP, 0, len(ips))
-	for _, ip := range ips {
-		parsedIP := ParseIPSloppy(ip)
-		parsedIPs = append(parsedIPs, parsedIP)
-	}
-	return IsDualStackIPs(parsedIPs)
-}
-
-// IsDualStackCIDRs returns if
-// - all are valid cidrs
-// - at least one cidr from each family (v4 or v6)
-func IsDualStackCIDRs(cidrs []*net.IPNet) (bool, error) {
-	v4Found := false
-	v6Found := false
-	for _, cidr := range cidrs {
-		if cidr == nil {
-			return false, fmt.Errorf("cidr %v is invalid", cidr)
-		}
-
-		if v4Found && v6Found {
-			continue
-		}
-
-		if IsIPv6(cidr.IP) {
-			v6Found = true
-			continue
-		}
-		v4Found = true
-	}
-
-	return v4Found && v6Found, nil
-}
-
-// IsDualStackCIDRStrings returns if
-// - all are valid cidrs
-// - at least one cidr from each family (v4 or v6)
-func IsDualStackCIDRStrings(cidrs []string) (bool, error) {
-	parsedCIDRs, err := ParseCIDRs(cidrs)
-	if err != nil {
-		return false, err
-	}
-	return IsDualStackCIDRs(parsedCIDRs)
-}
-
-// IsIPv6 returns if netIP is IPv6.
-func IsIPv6(netIP net.IP) bool {
-	return netIP != nil && netIP.To4() == nil
-}
-
-// IsIPv6String returns if ip is IPv6.
-func IsIPv6String(ip string) bool {
-	netIP := ParseIPSloppy(ip)
-	return IsIPv6(netIP)
-}
-
-// IsIPv6CIDRString returns if cidr is IPv6.
-// This assumes cidr is a valid CIDR.
-func IsIPv6CIDRString(cidr string) bool {
-	ip, _, _ := ParseCIDRSloppy(cidr)
-	return IsIPv6(ip)
-}
-
-// IsIPv6CIDR returns if a cidr is ipv6
-func IsIPv6CIDR(cidr *net.IPNet) bool {
-	ip := cidr.IP
-	return IsIPv6(ip)
-}
-
-// IsIPv4 returns if netIP is IPv4.
-func IsIPv4(netIP net.IP) bool {
-	return netIP != nil && netIP.To4() != nil
-}
-
-// IsIPv4String returns if ip is IPv4.
-func IsIPv4String(ip string) bool {
-	netIP := ParseIPSloppy(ip)
-	return IsIPv4(netIP)
-}
-
-// IsIPv4CIDR returns if a cidr is ipv4
-func IsIPv4CIDR(cidr *net.IPNet) bool {
-	ip := cidr.IP
-	return IsIPv4(ip)
-}
-
-// IsIPv4CIDRString returns if cidr is IPv4.
-// This assumes cidr is a valid CIDR.
-func IsIPv4CIDRString(cidr string) bool {
-	ip, _, _ := ParseCIDRSloppy(cidr)
-	return IsIPv4(ip)
-}
-
 // ParsePort parses a string representing an IP port.  If the string is not a
 // valid port number, this returns an error.
 func ParsePort(port string, allowZero bool) (int, error) {

vendor/k8s.io/utils/net/port.go

@@ -23,15 +23,6 @@ import (
 	"strings"
 )
 
-// IPFamily refers to a specific family if not empty, i.e. "4" or "6".
-type IPFamily string
-
-// Constants for valid IPFamilys:
-const (
-	IPv4 IPFamily = "4"
-	IPv6          = "6"
-)
-
 // Protocol is a network protocol support by LocalPort.
 type Protocol string
 
@@ -67,7 +58,7 @@ func NewLocalPort(desc, ip string, ipFamily IPFamily, port int, protocol Protoco
 	if protocol != TCP && protocol != UDP {
 		return nil, fmt.Errorf("Unsupported protocol %s", protocol)
 	}
-	if ipFamily != "" && ipFamily != "4" && ipFamily != "6" {
+	if ipFamily != IPFamilyUnknown && ipFamily != IPv4 && ipFamily != IPv6 {
 		return nil, fmt.Errorf("Invalid IP family %s", ipFamily)
 	}
 	if ip != "" {
@@ -75,9 +66,10 @@ func NewLocalPort(desc, ip string, ipFamily IPFamily, port int, protocol Protoco
 		if parsedIP == nil {
 			return nil, fmt.Errorf("invalid ip address %s", ip)
 		}
-		asIPv4 := parsedIP.To4()
-		if asIPv4 == nil && ipFamily == IPv4 || asIPv4 != nil && ipFamily == IPv6 {
-			return nil, fmt.Errorf("ip address and family mismatch %s, %s", ip, ipFamily)
+		if ipFamily != IPFamilyUnknown {
+			if IPFamily(parsedIP) != ipFamily {
+				return nil, fmt.Errorf("ip address and family mismatch %s, %s", ip, ipFamily)
+			}
 		}
 	}
 	return &LocalPort{Description: desc, IP: ip, IPFamily: ipFamily, Port: port, Protocol: protocol}, nil

vendor/k8s.io/utils/pointer/OWNERS

@@ -0,0 +1,10 @@
+# See the OWNERS docs at https://go.k8s.io/owners
+
+approvers:
+- apelisse
+- stewart-yu
+- thockin
+reviewers:
+- apelisse
+- stewart-yu
+- thockin

vendor/k8s.io/utils/pointer/README.md

@@ -0,0 +1,3 @@
+# Pointer
+
+This package provides some functions for pointer-based operations.

vendor/k8s.io/utils/pointer/pointer.go

@@ -0,0 +1,410 @@
+/*
+Copyright 2018 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package pointer
+
+import (
+	"fmt"
+	"reflect"
+	"time"
+)
+
+// AllPtrFieldsNil tests whether all pointer fields in a struct are nil.  This is useful when,
+// for example, an API struct is handled by plugins which need to distinguish
+// "no plugin accepted this spec" from "this spec is empty".
+//
+// This function is only valid for structs and pointers to structs.  Any other
+// type will cause a panic.  Passing a typed nil pointer will return true.
+func AllPtrFieldsNil(obj interface{}) bool {
+	v := reflect.ValueOf(obj)
+	if !v.IsValid() {
+		panic(fmt.Sprintf("reflect.ValueOf() produced a non-valid Value for %#v", obj))
+	}
+	if v.Kind() == reflect.Ptr {
+		if v.IsNil() {
+			return true
+		}
+		v = v.Elem()
+	}
+	for i := 0; i < v.NumField(); i++ {
+		if v.Field(i).Kind() == reflect.Ptr && !v.Field(i).IsNil() {
+			return false
+		}
+	}
+	return true
+}
+
+// Int returns a pointer to an int
+func Int(i int) *int {
+	return &i
+}
+
+// IntPtr is a function variable referring to Int.
+//
+// Deprecated: Use Int instead.
+var IntPtr = Int // for back-compat
+
+// IntDeref dereferences the int ptr and returns it if not nil, or else
+// returns def.
+func IntDeref(ptr *int, def int) int {
+	if ptr != nil {
+		return *ptr
+	}
+	return def
+}
+
+// IntPtrDerefOr is a function variable referring to IntDeref.
+//
+// Deprecated: Use IntDeref instead.
+var IntPtrDerefOr = IntDeref // for back-compat
+
+// Int32 returns a pointer to an int32.
+func Int32(i int32) *int32 {
+	return &i
+}
+
+// Int32Ptr is a function variable referring to Int32.
+//
+// Deprecated: Use Int32 instead.
+var Int32Ptr = Int32 // for back-compat
+
+// Int32Deref dereferences the int32 ptr and returns it if not nil, or else
+// returns def.
+func Int32Deref(ptr *int32, def int32) int32 {
+	if ptr != nil {
+		return *ptr
+	}
+	return def
+}
+
+// Int32PtrDerefOr is a function variable referring to Int32Deref.
+//
+// Deprecated: Use Int32Deref instead.
+var Int32PtrDerefOr = Int32Deref // for back-compat
+
+// Int32Equal returns true if both arguments are nil or both arguments
+// dereference to the same value.
+func Int32Equal(a, b *int32) bool {
+	if (a == nil) != (b == nil) {
+		return false
+	}
+	if a == nil {
+		return true
+	}
+	return *a == *b
+}
+
+// Uint returns a pointer to an uint
+func Uint(i uint) *uint {
+	return &i
+}
+
+// UintPtr is a function variable referring to Uint.
+//
+// Deprecated: Use Uint instead.
+var UintPtr = Uint // for back-compat
+
+// UintDeref dereferences the uint ptr and returns it if not nil, or else
+// returns def.
+func UintDeref(ptr *uint, def uint) uint {
+	if ptr != nil {
+		return *ptr
+	}
+	return def
+}
+
+// UintPtrDerefOr is a function variable referring to UintDeref.
+//
+// Deprecated: Use UintDeref instead.
+var UintPtrDerefOr = UintDeref // for back-compat
+
+// Uint32 returns a pointer to an uint32.
+func Uint32(i uint32) *uint32 {
+	return &i
+}
+
+// Uint32Ptr is a function variable referring to Uint32.
+//
+// Deprecated: Use Uint32 instead.
+var Uint32Ptr = Uint32 // for back-compat
+
+// Uint32Deref dereferences the uint32 ptr and returns it if not nil, or else
+// returns def.
+func Uint32Deref(ptr *uint32, def uint32) uint32 {
+	if ptr != nil {
+		return *ptr
+	}
+	return def
+}
+
+// Uint32PtrDerefOr is a function variable referring to Uint32Deref.
+//
+// Deprecated: Use Uint32Deref instead.
+var Uint32PtrDerefOr = Uint32Deref // for back-compat
+
+// Uint32Equal returns true if both arguments are nil or both arguments
+// dereference to the same value.
+func Uint32Equal(a, b *uint32) bool {
+	if (a == nil) != (b == nil) {
+		return false
+	}
+	if a == nil {
+		return true
+	}
+	return *a == *b
+}
+
+// Int64 returns a pointer to an int64.
+func Int64(i int64) *int64 {
+	return &i
+}
+
+// Int64Ptr is a function variable referring to Int64.
+//
+// Deprecated: Use Int64 instead.
+var Int64Ptr = Int64 // for back-compat
+
+// Int64Deref dereferences the int64 ptr and returns it if not nil, or else
+// returns def.
+func Int64Deref(ptr *int64, def int64) int64 {
+	if ptr != nil {
+		return *ptr
+	}
+	return def
+}
+
+// Int64PtrDerefOr is a function variable referring to Int64Deref.
+//
+// Deprecated: Use Int64Deref instead.
+var Int64PtrDerefOr = Int64Deref // for back-compat
+
+// Int64Equal returns true if both arguments are nil or both arguments
+// dereference to the same value.
+func Int64Equal(a, b *int64) bool {
+	if (a == nil) != (b == nil) {
+		return false
+	}
+	if a == nil {
+		return true
+	}
+	return *a == *b
+}
+
+// Uint64 returns a pointer to an uint64.
+func Uint64(i uint64) *uint64 {
+	return &i
+}
+
+// Uint64Ptr is a function variable referring to Uint64.
+//
+// Deprecated: Use Uint64 instead.
+var Uint64Ptr = Uint64 // for back-compat
+
+// Uint64Deref dereferences the uint64 ptr and returns it if not nil, or else
+// returns def.
+func Uint64Deref(ptr *uint64, def uint64) uint64 {
+	if ptr != nil {
+		return *ptr
+	}
+	return def
+}
+
+// Uint64PtrDerefOr is a function variable referring to Uint64Deref.
+//
+// Deprecated: Use Uint64Deref instead.
+var Uint64PtrDerefOr = Uint64Deref // for back-compat
+
+// Uint64Equal returns true if both arguments are nil or both arguments
+// dereference to the same value.
+func Uint64Equal(a, b *uint64) bool {
+	if (a == nil) != (b == nil) {
+		return false
+	}
+	if a == nil {
+		return true
+	}
+	return *a == *b
+}
+
+// Bool returns a pointer to a bool.
+func Bool(b bool) *bool {
+	return &b
+}
+
+// BoolPtr is a function variable referring to Bool.
+//
+// Deprecated: Use Bool instead.
+var BoolPtr = Bool // for back-compat
+
+// BoolDeref dereferences the bool ptr and returns it if not nil, or else
+// returns def.
+func BoolDeref(ptr *bool, def bool) bool {
+	if ptr != nil {
+		return *ptr
+	}
+	return def
+}
+
+// BoolPtrDerefOr is a function variable referring to BoolDeref.
+//
+// Deprecated: Use BoolDeref instead.
+var BoolPtrDerefOr = BoolDeref // for back-compat
+
+// BoolEqual returns true if both arguments are nil or both arguments
+// dereference to the same value.
+func BoolEqual(a, b *bool) bool {
+	if (a == nil) != (b == nil) {
+		return false
+	}
+	if a == nil {
+		return true
+	}
+	return *a == *b
+}
+
+// String returns a pointer to a string.
+func String(s string) *string {
+	return &s
+}
+
+// StringPtr is a function variable referring to String.
+//
+// Deprecated: Use String instead.
+var StringPtr = String // for back-compat
+
+// StringDeref dereferences the string ptr and returns it if not nil, or else
+// returns def.
+func StringDeref(ptr *string, def string) string {
+	if ptr != nil {
+		return *ptr
+	}
+	return def
+}
+
+// StringPtrDerefOr is a function variable referring to StringDeref.
+//
+// Deprecated: Use StringDeref instead.
+var StringPtrDerefOr = StringDeref // for back-compat
+
+// StringEqual returns true if both arguments are nil or both arguments
+// dereference to the same value.
+func StringEqual(a, b *string) bool {
+	if (a == nil) != (b == nil) {
+		return false
+	}
+	if a == nil {
+		return true
+	}
+	return *a == *b
+}
+
+// Float32 returns a pointer to a float32.
+func Float32(i float32) *float32 {
+	return &i
+}
+
+// Float32Ptr is a function variable referring to Float32.
+//
+// Deprecated: Use Float32 instead.
+var Float32Ptr = Float32
+
+// Float32Deref dereferences the float32 ptr and returns it if not nil, or else
+// returns def.
+func Float32Deref(ptr *float32, def float32) float32 {
+	if ptr != nil {
+		return *ptr
+	}
+	return def
+}
+
+// Float32PtrDerefOr is a function variable referring to Float32Deref.
+//
+// Deprecated: Use Float32Deref instead.
+var Float32PtrDerefOr = Float32Deref // for back-compat
+
+// Float32Equal returns true if both arguments are nil or both arguments
+// dereference to the same value.
+func Float32Equal(a, b *float32) bool {
+	if (a == nil) != (b == nil) {
+		return false
+	}
+	if a == nil {
+		return true
+	}
+	return *a == *b
+}
+
+// Float64 returns a pointer to a float64.
+func Float64(i float64) *float64 {
+	return &i
+}
+
+// Float64Ptr is a function variable referring to Float64.
+//
+// Deprecated: Use Float64 instead.
+var Float64Ptr = Float64
+
+// Float64Deref dereferences the float64 ptr and returns it if not nil, or else
+// returns def.
+func Float64Deref(ptr *float64, def float64) float64 {
+	if ptr != nil {
+		return *ptr
+	}
+	return def
+}
+
+// Float64PtrDerefOr is a function variable referring to Float64Deref.
+//
+// Deprecated: Use Float64Deref instead.
+var Float64PtrDerefOr = Float64Deref // for back-compat
+
+// Float64Equal returns true if both arguments are nil or both arguments
+// dereference to the same value.
+func Float64Equal(a, b *float64) bool {
+	if (a == nil) != (b == nil) {
+		return false
+	}
+	if a == nil {
+		return true
+	}
+	return *a == *b
+}
+
+// Duration returns a pointer to a time.Duration.
+func Duration(d time.Duration) *time.Duration {
+	return &d
+}
+
+// DurationDeref dereferences the time.Duration ptr and returns it if not nil, or else
+// returns def.
+func DurationDeref(ptr *time.Duration, def time.Duration) time.Duration {
+	if ptr != nil {
+		return *ptr
+	}
+	return def
+}
+
+// DurationEqual returns true if both arguments are nil or both arguments
+// dereference to the same value.
+func DurationEqual(a, b *time.Duration) bool {
+	if (a == nil) != (b == nil) {
+		return false
+	}
+	if a == nil {
+		return true
+	}
+	return *a == *b
+}