unix: support TIOCGETA on GNU/Hurd

Add minimal support for GNU/Hurd to allow building third party packages
which detect terminal support.

Change-Id: Ia13fe8e9e4880e8ab062f9a2efb581320637f017
GitHub-Last-Rev: f612efbe7da35f618d1bd498a215f4b9da9c4f53
GitHub-Pull-Request: golang/sys#144
Reviewed-on: https://go-review.googlesource.com/c/sys/+/459895
Reviewed-by: Tobias Klauser <tobias.klauser@gmail.com>
Auto-Submit: Ian Lance Taylor <iant@google.com>
Run-TryBot: Ian Lance Taylor <iant@google.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>
Run-TryBot: Tobias Klauser <tobias.klauser@gmail.com>
TryBot-Result: Gopher Robot <gobot@golang.org>

unix/gccgo.go

diff --git a/unix/gccgo.go b/unix/gccgo.go
index 0dee232..b06f52d 100644
--- a/unix/gccgo.go
+++ b/unix/gccgo.go
@@ -2,8 +2,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-//go:build gccgo && !aix
-// +build gccgo,!aix
+//go:build gccgo && !aix && !hurd
+// +build gccgo,!aix,!hurd
 
 package unix
 

unix/gccgo_c.c

diff --git a/unix/gccgo_c.c b/unix/gccgo_c.c
index 2cb1fef..c4fce0e 100644
--- a/unix/gccgo_c.c
+++ b/unix/gccgo_c.c
@@ -2,8 +2,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build gccgo
-// +build !aix
+// +build gccgo,!hurd
+// +build !aix,!hurd
 
 #include <errno.h>
 #include <stdint.h>

unix/ioctl.go

diff --git a/unix/ioctl.go b/unix/ioctl.go
index 6c7ad05..1c51b0e 100644
--- a/unix/ioctl.go
+++ b/unix/ioctl.go
@@ -2,8 +2,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-//go:build aix || darwin || dragonfly || freebsd || linux || netbsd || openbsd || solaris
-// +build aix darwin dragonfly freebsd linux netbsd openbsd solaris
+//go:build aix || darwin || dragonfly || freebsd || hurd || linux || netbsd || openbsd || solaris
+// +build aix darwin dragonfly freebsd hurd linux netbsd openbsd solaris
 
 package unix
 

unix/syscall_hurd.go

diff --git a/unix/syscall_hurd.go b/unix/syscall_hurd.go
new file mode 100644
index 0000000..93aa420
--- /dev/null
+++ b/unix/syscall_hurd.go
@@ -0,0 +1,23 @@
+// Copyright 2022 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 hurd
+// +build hurd
+
+package unix
+
+/*
+#include <stdint.h>
+int ioctl(int, unsigned long int, uintptr_t);
+*/
+import "C"
+
+func ioctl(fd int, req uint, arg uintptr) (err error) {
+	r0, er := C.ioctl(C.int(fd), C.ulong(req), C.uintptr_t(arg))
+	if r0 == -1 && er != nil {
+		err = er
+	}
+	return
+}
+

unix/syscall_hurd_386.go

diff --git a/unix/syscall_hurd_386.go b/unix/syscall_hurd_386.go
new file mode 100644
index 0000000..44f3c4b
--- /dev/null
+++ b/unix/syscall_hurd_386.go
@@ -0,0 +1,29 @@
+// Copyright 2022 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 386 && hurd
+// +build 386,hurd
+
+package unix
+
+const (
+	TIOCGETA                       = 0x62251713
+)
+
+type Winsize struct {
+	Row    uint16
+	Col    uint16
+	Xpixel uint16
+	Ypixel uint16
+}
+
+type Termios struct {
+	Iflag  uint32
+	Oflag  uint32
+	Cflag  uint32
+	Lflag  uint32
+	Cc     [20]uint8
+	Ispeed int32
+	Ospeed int32
+}