Cleanup and revise TTY interface

src/gopheros/device/tty/device.go

@@ -0,0 +1,44 @@
+package tty
+
+import (
+	"gopheros/device/video/console"
+	"io"
+)
+
+// State defines the supported terminal state values.
+type State uint8
+
+const (
+	// StateInactive marks the terminal as inactive. Any writes will be
+	// buffered and not synced to the attached console.
+	StateInactive State = iota
+
+	// StateActive marks the terminal as active. Any writes will be
+	// buffered and also synced to the attached console.
+	StateActive
+)
+
+// Device is implemented by objects that can be used as a terminal device.
+type Device interface {
+	io.Writer
+	io.ByteWriter
+
+	// AttachTo connects a TTY to a console instance.
+	AttachTo(console.Device)
+
+	// State returns the TTY's state.
+	State() State
+
+	// SetState updates the TTY's state.
+	SetState(State)
+
+	// CursorPosition returns the current cursor x,y coordinates. Both
+	// coordinates are 1-based (top-left corner has coordinates 1,1).
+	CursorPosition() (uint16, uint16)
+
+	// SetCursorPosition sets the current cursor position to (x,y). Both
+	// coordinates are 1-based (top-left corner has coordinates 1,1).
+	// Implementations are expected to clip the cursor position to their
+	// viewport.
+	SetCursorPosition(x, y uint16)
+}

src/gopheros/kernel/driver/tty/tty.go

@@ -1,19 +0,0 @@
-package tty
-
-import "io"
-
-// Tty is implemented by objects that can register themselves as ttys.
-type Tty interface {
-	io.Writer
-	io.ByteWriter
-
-	// Position returns the current cursor position (x, y).
-	Position() (uint16, uint16)
-
-	// SetPosition sets the current cursor position to (x,y). Console implementations
-	// must clip the provided cursor position if it exceeds the console dimensions.
-	SetPosition(x, y uint16)
-
-	// Clear clears the terminal.
-	Clear()
-}