ssh/terminal: implement missing functions for Solaris/OmniOS

    terminal.MakeRaw
    terminal.Restore
    terminal.GetState
    terminal.GetSize

Fixes golang/go#20062

Change-Id: I9ccf194215998c5b80dbedc4f248b481f0ca57a6
Reviewed-on: https://go-review.googlesource.com/41297
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
diff --git a/util_solaris.go b/util_solaris.go
index 07eb5ed..a2e1b57 100644
--- a/util_solaris.go
+++ b/util_solaris.go
@@ -14,14 +14,12 @@
 
 // State contains the state of a terminal.
 type State struct {
-	termios syscall.Termios
+	state *unix.Termios
 }
 
 // IsTerminal returns true if the given file descriptor is a terminal.
 func IsTerminal(fd int) bool {
-	// see: http://src.illumos.org/source/xref/illumos-gate/usr/src/lib/libbc/libc/gen/common/isatty.c
-	var termio unix.Termio
-	err := unix.IoctlSetTermio(fd, unix.TCGETA, &termio)
+	_, err := unix.IoctlGetTermio(fd, unix.TCGETA)
 	return err == nil
 }
 
@@ -71,3 +69,60 @@
 
 	return ret, nil
 }
+
+// MakeRaw puts the terminal connected to the given file descriptor into raw
+// mode and returns the previous state of the terminal so that it can be
+// restored.
+// see http://cr.illumos.org/~webrev/andy_js/1060/
+func MakeRaw(fd int) (*State, error) {
+	oldTermiosPtr, err := unix.IoctlGetTermios(fd, unix.TCGETS)
+	if err != nil {
+		return nil, err
+	}
+	oldTermios := *oldTermiosPtr
+
+	newTermios := oldTermios
+	newTermios.Iflag &^= syscall.IGNBRK | syscall.BRKINT | syscall.PARMRK | syscall.ISTRIP | syscall.INLCR | syscall.IGNCR | syscall.ICRNL | syscall.IXON
+	newTermios.Oflag &^= syscall.OPOST
+	newTermios.Lflag &^= syscall.ECHO | syscall.ECHONL | syscall.ICANON | syscall.ISIG | syscall.IEXTEN
+	newTermios.Cflag &^= syscall.CSIZE | syscall.PARENB
+	newTermios.Cflag |= syscall.CS8
+	newTermios.Cc[unix.VMIN] = 1
+	newTermios.Cc[unix.VTIME] = 0
+
+	if err := unix.IoctlSetTermios(fd, unix.TCSETS, &newTermios); err != nil {
+		return nil, err
+	}
+
+	return &State{
+		state: oldTermiosPtr,
+	}, nil
+}
+
+// Restore restores the terminal connected to the given file descriptor to a
+// previous state.
+func Restore(fd int, oldState *State) error {
+	return unix.IoctlSetTermios(fd, unix.TCSETS, oldState.state)
+}
+
+// GetState returns the current state of a terminal which may be useful to
+// restore the terminal after a signal.
+func GetState(fd int) (*State, error) {
+	oldTermiosPtr, err := unix.IoctlGetTermios(fd, unix.TCGETS)
+	if err != nil {
+		return nil, err
+	}
+
+	return &State{
+		state: oldTermiosPtr,
+	}, nil
+}
+
+// GetSize returns the dimensions of the given terminal.
+func GetSize(fd int) (width, height int, err error) {
+	ws, err := unix.IoctlGetWinsize(fd, unix.TIOCGWINSZ)
+	if err != nil {
+		return 0, 0, err
+	}
+	return int(ws.Col), int(ws.Row), nil
+}