net: run unix socket stream tests on Windows

The net package supports Unix domain sockets on Windows, but most of
the tests related to them are skipped.

This CL unskip the SOCK_STREAM tests. SOCK_DGRAM probablye can also
make to work, but that will come in a follow-up CL.

Change-Id: If9506a8af57e9bfe58bd7b48a98fc39335627a61
Reviewed-on: https://go-review.googlesource.com/c/go/+/660915
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Damien Neil <dneil@google.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>

6 files changed, 82 insertions, 25 deletions

diff --git a/src/net/platform_plan9_test.go b/src/net/platform_plan9_test.go
new file mode 100644
index 0000000000..e1ca0aadae
--- /dev/null
+++ b/src/net/platform_plan9_test.go
@@ -0,0 +1,9 @@
+// Copyright 2025 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.
+
+package net
+
+func supportsUnixSocket() bool {
+	return false
+}
diff --git a/src/net/platform_test.go b/src/net/platform_test.go
index 709d4a3eb7..f8317104d0 100644
--- a/src/net/platform_test.go
+++ b/src/net/platform_test.go
@@ -7,30 +7,11 @@ package net
 import (
 	"internal/testenv"
 	"os"
-	"os/exec"
 	"runtime"
-	"strconv"
 	"strings"
 	"testing"
 )
 
-var unixEnabledOnAIX bool
-
-func init() {
-	if runtime.GOOS == "aix" {
-		// Unix network isn't properly working on AIX 7.2 with
-		// Technical Level < 2.
-		// The information is retrieved only once in this init()
-		// instead of everytime testableNetwork is called.
-		out, _ := exec.Command("oslevel", "-s").Output()
-		if len(out) >= len("7200-XX-ZZ-YYMM") { // AIX 7.2, Tech Level XX, Service Pack ZZ, date YYMM
-			aixVer := string(out[:4])
-			tl, _ := strconv.Atoi(string(out[5:7]))
-			unixEnabledOnAIX = aixVer > "7200" || (aixVer == "7200" && tl >= 2)
-		}
-	}
-}
-
 // testableNetwork reports whether network is testable on the current
 // platform configuration.
 func testableNetwork(network string) bool {
@@ -46,13 +27,15 @@ func testableNetwork(network string) bool {
 				return false
 			}
 		}
-	case "unix", "unixgram":
+	case "unixgram":
 		switch runtime.GOOS {
-		case "android", "ios", "plan9", "windows":
+		case "windows":
 			return false
-		case "aix":
-			return unixEnabledOnAIX
+		default:
+			return supportsUnixSocket()
 		}
+	case "unix":
+		return supportsUnixSocket()
 	case "unixpacket":
 		switch runtime.GOOS {
 		case "aix", "android", "darwin", "ios", "plan9", "windows":
diff --git a/src/net/platform_unix_test.go b/src/net/platform_unix_test.go
new file mode 100644
index 0000000000..b6b3a5549d
--- /dev/null
+++ b/src/net/platform_unix_test.go
@@ -0,0 +1,40 @@
+// Copyright 2025 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.
+
+//go:build unix || js || wasip1
+
+package net
+
+import (
+	"os/exec"
+	"runtime"
+	"strconv"
+)
+
+var unixEnabledOnAIX bool
+
+func init() {
+	if runtime.GOOS == "aix" {
+		// Unix network isn't properly working on AIX 7.2 with
+		// Technical Level < 2.
+		// The information is retrieved only once in this init()
+		// instead of everytime testableNetwork is called.
+		out, _ := exec.Command("oslevel", "-s").Output()
+		if len(out) >= len("7200-XX-ZZ-YYMM") { // AIX 7.2, Tech Level XX, Service Pack ZZ, date YYMM
+			aixVer := string(out[:4])
+			tl, _ := strconv.Atoi(string(out[5:7]))
+			unixEnabledOnAIX = aixVer > "7200" || (aixVer == "7200" && tl >= 2)
+		}
+	}
+}
+
+func supportsUnixSocket() bool {
+	switch runtime.GOOS {
+	case "android", "ios":
+		return false
+	case "aix":
+		return unixEnabledOnAIX
+	}
+	return true
+}
diff --git a/src/net/platform_windows_test.go b/src/net/platform_windows_test.go
new file mode 100644
index 0000000000..ec2c861e80
--- /dev/null
+++ b/src/net/platform_windows_test.go
@@ -0,0 +1,11 @@
+// Copyright 2025 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.
+
+package net
+
+import "internal/syscall/windows"
+
+func supportsUnixSocket() bool {
+	return windows.SupportUnixSocket()
+}
diff --git a/src/net/rawconn_windows_test.go b/src/net/rawconn_windows_test.go
index 5febf08f77..ebfec3499a 100644
--- a/src/net/rawconn_windows_test.go
+++ b/src/net/rawconn_windows_test.go
@@ -95,6 +95,11 @@ func controlOnConnSetup(network string, address string, c syscall.RawConn) error
 	switch network {
 	case "tcp", "udp", "ip":
 		return errors.New("ambiguous network: " + network)
+	case "unix", "unixpacket", "unixgram":
+		fn = func(s uintptr) {
+			const SO_ERROR = 0x1007
+			_, operr = syscall.GetsockoptInt(syscall.Handle(s), syscall.SOL_SOCKET, SO_ERROR)
+		}
 	default:
 		switch network[len(network)-1] {
 		case '4':
diff --git a/src/net/unixsock_test.go b/src/net/unixsock_test.go
index 6906ecc046..1bbe53db10 100644
--- a/src/net/unixsock_test.go
+++ b/src/net/unixsock_test.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.
 
-//go:build !plan9 && !windows
+//go:build !plan9
 
 package net
 
@@ -282,7 +282,7 @@ func TestUnixConnLocalAndRemoteNames(t *testing.T) {
 		}
 
 		switch runtime.GOOS {
-		case "android", "linux":
+		case "android", "linux", "windows":
 			if laddr == "" {
 				laddr = "@" // autobind feature
 			}
@@ -398,6 +398,9 @@ func TestUnixUnlink(t *testing.T) {
 
 	// FileListener should not.
 	t.Run("FileListener", func(t *testing.T) {
+		if runtime.GOOS == "windows" {
+			t.Skip("skipping: FileListener not implemented on windows")
+		}
 		l := listen(t)
 		f, _ := l.File()
 		l1, _ := FileListener(f)
@@ -445,6 +448,9 @@ func TestUnixUnlink(t *testing.T) {
 	})
 
 	t.Run("FileListener/SetUnlinkOnClose(true)", func(t *testing.T) {
+		if runtime.GOOS == "windows" {
+			t.Skip("skipping: FileListener not implemented on windows")
+		}
 		l := listen(t)
 		f, _ := l.File()
 		l1, _ := FileListener(f)
@@ -458,6 +464,9 @@ func TestUnixUnlink(t *testing.T) {
 	})
 
 	t.Run("FileListener/SetUnlinkOnClose(false)", func(t *testing.T) {
+		if runtime.GOOS == "windows" {
+			t.Skip("skipping: FileListener not implemented on windows")
+		}
 		l := listen(t)
 		f, _ := l.File()
 		l1, _ := FileListener(f)