net: revise for go1.12

gosrc/net/addrselect.go

@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build darwin dragonfly freebsd linux netbsd openbsd solaris
+// +build aix darwin dragonfly freebsd linux netbsd openbsd solaris
 
 // Minimal RFC 6724 address selection.
 

gosrc/net/cgo_stub.go

@@ -24,7 +24,7 @@ func cgoLookupPort(ctx context.Context, network, service string) (port int, err
 	return 0, nil, false
 }
 
-func cgoLookupIP(ctx context.Context, name string) (addrs []IPAddr, err error, completed bool) {
+func cgoLookupIP(ctx context.Context, network, name string) (addrs []IPAddr, err error, completed bool) {
 	return nil, nil, false
 }
 

gosrc/net/cgo_unix.go

@@ -49,7 +49,7 @@ type reverseLookupResult struct {
 }
 
 func cgoLookupHost(ctx context.Context, name string) (hosts []string, err error, completed bool) {
-	addrs, err, completed := cgoLookupIP(ctx, name)
+	addrs, err, completed := cgoLookupIP(ctx, "ip", name)
 	for _, addr := range addrs {
 		hosts = append(hosts, addr.String())
 	}
@@ -69,13 +69,11 @@ func cgoLookupPort(ctx context.Context, network, service string) (port int, err
 	default:
 		return 0, &DNSError{Err: "unknown network", Name: network + "/" + service}, true
 	}
-	if len(network) >= 4 {
-		switch network[3] {
-		case '4':
-			hints.ai_family = C.AF_INET
-		case '6':
-			hints.ai_family = C.AF_INET6
-		}
+	switch ipVersion(network) {
+	case '4':
+		hints.ai_family = C.AF_INET
+	case '6':
+		hints.ai_family = C.AF_INET6
 	}
 	if ctx.Done() == nil {
 		port, err := cgoLookupServicePort(&hints, network, service)
@@ -135,13 +133,20 @@ func cgoPortLookup(result chan<- portLookupResult, hints *C.struct_addrinfo, net
 	result <- portLookupResult{port, err}
 }
 
-func cgoLookupIPCNAME(name string) (addrs []IPAddr, cname string, err error) {
+func cgoLookupIPCNAME(network, name string) (addrs []IPAddr, cname string, err error) {
 	acquireThread()
 	defer releaseThread()
 
 	var hints C.struct_addrinfo
 	hints.ai_flags = cgoAddrInfoFlags
 	hints.ai_socktype = C.SOCK_STREAM
+	hints.ai_family = C.AF_UNSPEC
+	switch ipVersion(network) {
+	case '4':
+		hints.ai_family = C.AF_INET
+	case '6':
+		hints.ai_family = C.AF_INET6
+	}
 
 	h := make([]byte, len(name)+1)
 	copy(h, name)
@@ -197,18 +202,18 @@ func cgoLookupIPCNAME(name string) (addrs []IPAddr, cname string, err error) {
 	return addrs, cname, nil
 }
 
-func cgoIPLookup(result chan<- ipLookupResult, name string) {
-	addrs, cname, err := cgoLookupIPCNAME(name)
+func cgoIPLookup(result chan<- ipLookupResult, network, name string) {
+	addrs, cname, err := cgoLookupIPCNAME(network, name)
 	result <- ipLookupResult{addrs, cname, err}
 }
 
-func cgoLookupIP(ctx context.Context, name string) (addrs []IPAddr, err error, completed bool) {
+func cgoLookupIP(ctx context.Context, network, name string) (addrs []IPAddr, err error, completed bool) {
 	if ctx.Done() == nil {
-		addrs, _, err = cgoLookupIPCNAME(name)
+		addrs, _, err = cgoLookupIPCNAME(network, name)
 		return addrs, err, true
 	}
 	result := make(chan ipLookupResult, 1)
-	go cgoIPLookup(result, name)
+	go cgoIPLookup(result, network, name)
 	select {
 	case r := <-result:
 		return r.addrs, r.err, true
@@ -219,11 +224,11 @@ func cgoLookupIP(ctx context.Context, name string) (addrs []IPAddr, err error, c
 
 func cgoLookupCNAME(ctx context.Context, name string) (cname string, err error, completed bool) {
 	if ctx.Done() == nil {
-		_, cname, err = cgoLookupIPCNAME(name)
+		_, cname, err = cgoLookupIPCNAME("ip", name)
 		return cname, err, true
 	}
 	result := make(chan ipLookupResult, 1)
-	go cgoIPLookup(result, name)
+	go cgoIPLookup(result, "ip", name)
 	select {
 	case r := <-result:
 		return r.cname, r.err, true

gosrc/net/conf.go

@@ -2,11 +2,12 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build darwin dragonfly freebsd linux netbsd openbsd solaris
+// +build aix darwin dragonfly freebsd linux netbsd openbsd solaris
 
 package net
 
 import (
+	"internal/bytealg"
 	"os"
 	"runtime"
 	"sync"
@@ -132,7 +133,7 @@ func (c *conf) hostLookupOrder(r *Resolver, hostname string) (ret hostLookupOrde
 	if c.forceCgoLookupHost || c.resolv.unknownOpt || c.goos == "android" {
 		return fallbackOrder
 	}
-	if byteIndex(hostname, '\\') != -1 || byteIndex(hostname, '%') != -1 {
+	if bytealg.IndexByteString(hostname, '\\') != -1 || bytealg.IndexByteString(hostname, '%') != -1 {
 		// Don't deal with special form hostnames with backslashes
 		// or '%'.
 		return fallbackOrder
@@ -301,7 +302,7 @@ func goDebugNetDNS() (dnsMode string, debugLevel int) {
 			dnsMode = s
 		}
 	}
-	if i := byteIndex(goDebug, '+'); i != -1 {
+	if i := bytealg.IndexByteString(goDebug, '+'); i != -1 {
 		parsePart(goDebug[:i])
 		parsePart(goDebug[i+1:])
 		return

gosrc/net/dial.go

@@ -44,22 +44,31 @@ type Dialer struct {
 	// If nil, a local address is automatically chosen.
 	LocalAddr Addr
 
-	// DualStack enables RFC 6555-compliant "Happy Eyeballs"
-	// dialing when the network is "tcp" and the host in the
-	// address parameter resolves to both IPv4 and IPv6 addresses.
-	// This allows a client to tolerate networks where one address
-	// family is silently broken.
+	// DualStack previously enabled RFC 6555 Fast Fallback
+	// support, also known as "Happy Eyeballs", in which IPv4 is
+	// tried soon if IPv6 appears to be misconfigured and
+	// hanging.
+	//
+	// Deprecated: Fast Fallback is enabled by default. To
+	// disable, set FallbackDelay to a negative value.
 	DualStack bool
 
 	// FallbackDelay specifies the length of time to wait before
-	// spawning a fallback connection, when DualStack is enabled.
+	// spawning a RFC 6555 Fast Fallback connection. That is, this
+	// is the amount of time to wait for IPv6 to succeed before
+	// assuming that IPv6 is misconfigured and falling back to
+	// IPv4.
+	//
 	// If zero, a default delay of 300ms is used.
+	// A negative value disables Fast Fallback support.
 	FallbackDelay time.Duration
 
 	// KeepAlive specifies the keep-alive period for an active
 	// network connection.
-	// If zero, keep-alives are not enabled. Network protocols
+	// If zero, keep-alives are enabled if supported by the protocol
+	// and operating system. Network protocols or operating systems
 	// that do not support keep-alives ignore this field.
+	// If negative, keep-alives are disabled.
 	KeepAlive time.Duration
 
 	// Resolver optionally specifies an alternate resolver to use.
@@ -81,6 +90,8 @@ type Dialer struct {
 	Control func(network, address string, c syscall.RawConn) error
 }
 
+func (d *Dialer) dualStack() bool { return d.FallbackDelay >= 0 }
+
 func minNonzeroTime(a, b time.Time) time.Time {
 	if a.IsZero() {
 		return b
@@ -393,7 +404,7 @@ func (d *Dialer) DialContext(ctx context.Context, network, address string) (Conn
 	}
 
 	var primaries, fallbacks addrList
-	if d.DualStack && network == "tcp" {
+	if d.dualStack() && network == "tcp" {
 		primaries, fallbacks = addrs.partition(isIPv4)
 	} else {
 		primaries = addrs
@@ -409,10 +420,14 @@ func (d *Dialer) DialContext(ctx context.Context, network, address string) (Conn
 		return nil, err
 	}
 
-	if tc, ok := c.(*TCPConn); ok && d.KeepAlive > 0 {
+	if tc, ok := c.(*TCPConn); ok && d.KeepAlive >= 0 {
 		setKeepAlive(tc.fd, true)
-		setKeepAlivePeriod(tc.fd, d.KeepAlive)
-		testHookSetKeepAlive()
+		ka := d.KeepAlive
+		if d.KeepAlive == 0 {
+			ka = 15 * time.Second
+		}
+		setKeepAlivePeriod(tc.fd, ka)
+		testHookSetKeepAlive(ka)
 	}
 	return c, nil
 }

gosrc/net/dnsclient.go

@@ -8,7 +8,7 @@ import (
 	"math/rand"
 	"sort"
 
-	"golang_org/x/net/dns/dnsmessage"
+	"internal/x/net/dns/dnsmessage"
 )
 
 // reverseaddr returns the in-addr.arpa. or ip6.arpa. hostname of the IP
@@ -27,10 +27,10 @@ func reverseaddr(addr string) (arpa string, err error) {
 	// Add it, in reverse, to the buffer
 	for i := len(ip) - 1; i >= 0; i-- {
 		v := ip[i]
-		buf = append(buf, hexDigit[v&0xF])
-		buf = append(buf, '.')
-		buf = append(buf, hexDigit[v>>4])
-		buf = append(buf, '.')
+		buf = append(buf, hexDigit[v&0xF],
+			'.',
+			hexDigit[v>>4],
+			'.')
 	}
 	// Append "ip6.arpa." and return (buf already has the final .)
 	buf = append(buf, "ip6.arpa."...)
@@ -75,15 +75,15 @@ func isDomainName(s string) bool {
 	}
 
 	last := byte('.')
-	ok := false // Ok once we've seen a letter.
+	nonNumeric := false // true once we've seen a letter or hyphen
 	partlen := 0
 	for i := 0; i < len(s); i++ {
 		c := s[i]
 		switch {
 		default:
 			return false
 		case 'a' <= c && c <= 'z' || 'A' <= c && c <= 'Z' || c == '_':
-			ok = true
+			nonNumeric = true
 			partlen++
 		case '0' <= c && c <= '9':
 			// fine
@@ -94,6 +94,7 @@ func isDomainName(s string) bool {
 				return false
 			}
 			partlen++
+			nonNumeric = true
 		case c == '.':
 			// Byte before dot cannot be dot, dash.
 			if last == '.' || last == '-' {
@@ -110,7 +111,7 @@ func isDomainName(s string) bool {
 		return false
 	}
 
-	return ok
+	return nonNumeric
 }
 
 // absDomainName returns an absolute domain name which ends with a

gosrc/net/dnsclient_unix.go

@@ -2,14 +2,13 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build darwin dragonfly freebsd linux netbsd openbsd solaris
+// +build aix darwin dragonfly freebsd linux netbsd openbsd solaris
 
 // DNS client: see RFC 1035.
 // Has to be linked into package net for Dial.
 
 // TODO(rsc):
 //	Could potentially handle many outstanding lookups faster.
-//	Could have a small cache.
 //	Random UDP source port (net.Dial should do that for us).
 //	Random request IDs.
 
@@ -24,7 +23,7 @@ import (
 	"sync"
 	"time"
 
-	"golang_org/x/net/dns/dnsmessage"
+	"internal/x/net/dns/dnsmessage"
 )
 
 var (

gosrc/net/dnsconfig_unix.go

@@ -2,13 +2,14 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build darwin dragonfly freebsd linux netbsd openbsd solaris
+// +build aix darwin dragonfly freebsd linux netbsd openbsd solaris
 
 // Read system DNS config from /etc/resolv.conf
 
 package net
 
 import (
+	"internal/bytealg"
 	"os"
 	"sync/atomic"
 	"time"
@@ -155,7 +156,7 @@ func dnsDefaultSearch() []string {
 		// best effort
 		return nil
 	}
-	if i := byteIndex(hn, '.'); i >= 0 && i < len(hn)-1 {
+	if i := bytealg.IndexByteString(hn, '.'); i >= 0 && i < len(hn)-1 {
 		return []string{ensureRooted(hn[i+1:])}
 	}
 	return nil

gosrc/net/error_posix.go

@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build darwin dragonfly freebsd js,wasm linux nacl netbsd openbsd solaris windows
+// +build aix darwin dragonfly freebsd js,wasm linux nacl netbsd openbsd solaris windows
 
 package net
 

gosrc/net/error_unix.go

@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build darwin dragonfly freebsd js linux netbsd openbsd solaris
+// +build aix darwin dragonfly freebsd js linux netbsd openbsd solaris
 
 package net
 

gosrc/net/fd_unix.go

@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build darwin dragonfly freebsd linux nacl netbsd openbsd solaris
+// +build aix darwin dragonfly freebsd linux nacl netbsd openbsd solaris
 
 package net