net: consolidate the existing Windows version checks

Change-Id: I9c0ad69bd61923e9e272f157dc380a9120f08423
Reviewed-on: https://go-review.googlesource.com/c/go/+/565595
Reviewed-by: Bryan Mills <bcmills@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Damien Neil <dneil@google.com>

diff --git a/src/internal/syscall/windows/net_windows.go b/src/internal/syscall/windows/net_windows.go
index 42c600c1447df674a46ab745a596d04c7f323190..9fa5ecf8408321943e0085b294ea475ede4487d4 100644 (file)
--- a/src/internal/syscall/windows/net_windows.go
+++ b/src/internal/syscall/windows/net_windows.go
@@ -5,7 +5,6 @@
 package windows
 
 import (
-       "sync"
        "syscall"
        _ "unsafe"
 )
@@ -28,13 +27,3 @@ type TCP_INITIAL_RTO_PARAMETERS struct {
        Rtt                   uint16
        MaxSynRetransmissions uint8
 }
-
-var Support_TCP_INITIAL_RTO_NO_SYN_RETRANSMISSIONS = sync.OnceValue(func() bool {
-       var maj, min, build uint32
-       rtlGetNtVersionNumbers(&maj, &min, &build)
-       return maj >= 10 && build&0xffff >= 16299
-})
-
-//go:linkname rtlGetNtVersionNumbers syscall.rtlGetNtVersionNumbers
-//go:noescape
-func rtlGetNtVersionNumbers(majorVersion *uint32, minorVersion *uint32, buildNumber *uint32)

diff --git a/src/internal/syscall/windows/version_windows.go b/src/internal/syscall/windows/version_windows.go
index c0861ec509ae145f15b7629747e7a3b6a8b99e56..f0abb5d5a23201885a1bcc00f5ed6b1f74735eac 100644 (file)
--- a/src/internal/syscall/windows/version_windows.go
+++ b/src/internal/syscall/windows/version_windows.go
@@ -4,7 +4,10 @@
 
 package windows
 
-import "sync"
+import (
+       "sync"
+       _ "unsafe" // for linkname
+)
 
 // Version retrieves the major, minor, and build version numbers
 // of the current Windows OS from the RtlGetNtVersionNumbers API
@@ -15,6 +18,10 @@ func Version() (major, minor, build uint32) {
        return
 }
 
+//go:linkname rtlGetNtVersionNumbers syscall.rtlGetNtVersionNumbers
+//go:noescape
+func rtlGetNtVersionNumbers(majorVersion *uint32, minorVersion *uint32, buildNumber *uint32)
+
 // SupportFullTCPKeepAlive indicates whether the current Windows version
 // supports the full TCP keep-alive configurations, the minimal requirement
 // is Windows 10, version 1709.
@@ -22,3 +29,18 @@ var SupportFullTCPKeepAlive = sync.OnceValue(func() bool {
        major, _, build := Version()
        return major >= 10 && build >= 16299
 })
+
+// SupportTCPInitialRTONoSYNRetransmissions indicates whether the current
+// Windows version supports the TCP_INITIAL_RTO_NO_SYN_RETRANSMISSIONS, the
+// minimal requirement is Windows 10.0.16299.
+var SupportTCPInitialRTONoSYNRetransmissions = sync.OnceValue(func() bool {
+       major, _, build := Version()
+       return major >= 10 && build >= 16299
+})
+
+// SupportUnixSocket indicates whether the current Windows version supports
+// Unix Domain Sockets, the minimal requirement is Windows 10, build 17063.
+var SupportUnixSocket = sync.OnceValue(func() bool {
+       major, _, build := Version()
+       return major >= 10 && build >= 17063
+})

diff --git a/src/net/fd_windows.go b/src/net/fd_windows.go
index 254a5d491e1d1a757b38471f5a0000b419684071..5d7a1d54c31a32f3f4d023c71c550a71c93e36f8 100644 (file)
--- a/src/net/fd_windows.go
+++ b/src/net/fd_windows.go
@@ -135,7 +135,7 @@ func (fd *netFD) connect(ctx context.Context, la, ra syscall.Sockaddr) (syscall.
                        Rtt:                   windows.TCP_INITIAL_RTO_UNSPECIFIED_RTT, // use the default or overridden by the Administrator
                        MaxSynRetransmissions: 1,                                       // minimum possible value before Windows 10.0.16299
                }
-               if windows.Support_TCP_INITIAL_RTO_NO_SYN_RETRANSMISSIONS() {
+               if windows.SupportTCPInitialRTONoSYNRetransmissions() {
                        // In Windows 10.0.16299 TCP_INITIAL_RTO_NO_SYN_RETRANSMISSIONS makes ConnectEx() fails instantly.
                        params.MaxSynRetransmissions = windows.TCP_INITIAL_RTO_NO_SYN_RETRANSMISSIONS
                }

diff --git a/src/net/unixsock_windows_test.go b/src/net/unixsock_windows_test.go
index 1e54d6171a41ce9fe90b32b4c208298f47088889..585136b42f2d826a19d03990a2b48446882ab5a7 100644 (file)
--- a/src/net/unixsock_windows_test.go
+++ b/src/net/unixsock_windows_test.go
@@ -7,34 +7,15 @@
 package net
 
 import (
-       "internal/syscall/windows/registry"
+       "internal/syscall/windows"
        "os"
        "reflect"
        "runtime"
-       "strconv"
        "testing"
 )
 
-func isBuild17063() bool {
-       k, err := registry.OpenKey(registry.LOCAL_MACHINE, `SOFTWARE\Microsoft\Windows NT\CurrentVersion`, registry.READ)
-       if err != nil {
-               return false
-       }
-       defer k.Close()
-
-       s, _, err := k.GetStringValue("CurrentBuild")
-       if err != nil {
-               return false
-       }
-       ver, err := strconv.Atoi(s)
-       if err != nil {
-               return false
-       }
-       return ver >= 17063
-}
-
 func skipIfUnixSocketNotSupported(t *testing.T) {
-       // TODO: the isBuild17063 check should be enough, investigate why 386 and arm
+       // TODO: the windows.SupportUnixSocket check should be enough, investigate why 386 and arm
        // can't run these tests on newer Windows.
        switch runtime.GOARCH {
        case "386":
@@ -42,7 +23,7 @@ func skipIfUnixSocketNotSupported(t *testing.T) {
        case "arm":
                t.Skip("not supported on windows/arm, see golang.org/issue/28061")
        }
-       if !isBuild17063() {
+       if !windows.SupportUnixSocket() {
                t.Skip("unix test")
        }
 }