fix: make terminal raw in ssh command on windows

deansheather · deansheather · commit 500695dddae0 · 2024-04-17T17:12:00.000Z
We were making it raw, but not raw enough. It needs a few extra modes
enabled to function with arrows etc.
diff --git a/cli/ssh.go b/cli/ssh.go
@@ -25,19 +25,18 @@ import (
 	"golang.org/x/xerrors"
 	"gvisor.dev/gvisor/pkg/tcpip/adapters/gonet"
 
-	"github.com/coder/retry"
-	"github.com/coder/serpent"
-
 	"cdr.dev/slog"
 	"cdr.dev/slog/sloggers/sloghuman"
-
 	"github.com/coder/coder/v2/cli/cliui"
 	"github.com/coder/coder/v2/cli/cliutil"
+	"github.com/coder/coder/v2/cli/xterminal"
 	"github.com/coder/coder/v2/coderd/autobuild/notify"
 	"github.com/coder/coder/v2/coderd/util/ptr"
 	"github.com/coder/coder/v2/codersdk"
 	"github.com/coder/coder/v2/codersdk/workspacesdk"
 	"github.com/coder/coder/v2/cryptorand"
+	"github.com/coder/retry"
+	"github.com/coder/serpent"
 )
 
 var (
@@ -341,15 +340,22 @@ func (r *RootCmd) ssh() *serpent.Command {
 				}
 			}
 
-			stdoutFile, validOut := inv.Stdout.(*os.File)
 			stdinFile, validIn := inv.Stdin.(*os.File)
-			if validOut && validIn && isatty.IsTerminal(stdoutFile.Fd()) {
-				state, err := term.MakeRaw(int(stdinFile.Fd()))
+			stdoutFile, validOut := inv.Stdout.(*os.File)
+			if validIn && validOut && isatty.IsTerminal(stdinFile.Fd()) && isatty.IsTerminal(stdoutFile.Fd()) {
+				inState, err := xterminal.MakeInputRaw(stdinFile.Fd())
+				if err != nil {
+					return err
+				}
+				defer func() {
+					_ = xterminal.Restore(stdinFile.Fd(), inState)
+				}()
+				outState, err := xterminal.MakeOutputRaw(stdoutFile.Fd())
 				if err != nil {
 					return err
 				}
 				defer func() {
-					_ = term.Restore(int(stdinFile.Fd()), state)
+					_ = xterminal.Restore(stdoutFile.Fd(), outState)
 				}()
 
 				windowChange := listenWindowSize(ctx)
diff --git a/cli/xterminal/terminal.go b/cli/xterminal/terminal.go
@@ -0,0 +1,40 @@
+//go:build !windows
+// +build !windows
+
+package xterminal
+
+import (
+	"golang.org/x/term"
+)
+
+// State differs per-platform.
+type State struct {
+	s *term.State
+}
+
+// MakeInputRaw calls term.MakeRaw on non-Windows platforms.
+func MakeInputRaw(fd uintptr) (*State, error) {
+	s, err := term.MakeRaw(int(fd))
+	if err != nil {
+		return nil, err
+	}
+	return &State{
+		s: s,
+	}, nil
+}
+
+// MakeOutputRaw does nothing on non-Windows platforms.
+func MakeOutputRaw(_ uintptr) (*State, error) {
+	return &State{
+		s: nil,
+	}, nil
+}
+
+// Restore terminal back to original state.
+func Restore(fd uintptr, state *State) error {
+	if state == nil || state.s == nil {
+		return nil
+	}
+
+	return term.Restore(int(fd), state.s)
+}
diff --git a/cli/xterminal/terminal_windows.go b/cli/xterminal/terminal_windows.go
@@ -0,0 +1,59 @@
+//go:build windows
+// +build windows
+
+package xterminal
+
+import (
+	"golang.org/x/sys/windows"
+)
+
+// State differs per-platform.
+type State struct {
+	mode uint32
+}
+
+// makeRaw sets the terminal in raw mode and returns the previous state so it can be restored.
+func makeRaw(handle windows.Handle, input bool) (uint32, error) {
+	var prevState uint32
+	if err := windows.GetConsoleMode(handle, &prevState); err != nil {
+		return 0, err
+	}
+
+	var raw uint32
+	if input {
+		raw = prevState &^ (windows.ENABLE_ECHO_INPUT | windows.ENABLE_PROCESSED_INPUT | windows.ENABLE_LINE_INPUT | windows.ENABLE_PROCESSED_OUTPUT)
+		raw |= windows.ENABLE_VIRTUAL_TERMINAL_INPUT
+	} else {
+		raw = prevState | windows.ENABLE_VIRTUAL_TERMINAL_PROCESSING
+	}
+
+	if err := windows.SetConsoleMode(handle, raw); err != nil {
+		return 0, err
+	}
+	return prevState, nil
+}
+
+// MakeInputRaw sets an input terminal to raw and enables VT100 processing.
+func MakeInputRaw(handle uintptr) (*State, error) {
+	prevState, err := makeRaw(windows.Handle(handle), true)
+	if err != nil {
+		return nil, err
+	}
+
+	return &State{mode: prevState}, nil
+}
+
+// MakeOutputRaw sets an output terminal to raw and enables VT100 processing.
+func MakeOutputRaw(handle uintptr) (*State, error) {
+	prevState, err := makeRaw(windows.Handle(handle), false)
+	if err != nil {
+		return nil, err
+	}
+
+	return &State{mode: prevState}, nil
+}
+
+// Restore terminal back to original state.
+func Restore(handle uintptr, state *State) error {
+	return windows.SetConsoleMode(windows.Handle(handle), state.mode)
+}
