windows: add console input api

This adds multiple functions to read, count, and discard console
input events. Using `ReadConsoleInput` instead of `ReadConsole` or
`ReadFile` is necessary to capture extended events such as window
resize, focus, and extended key and mouse events.

This also define console event types and structs.

Author: aymanbagabas

windows/syscall_windows.go

@@ -319,6 +319,10 @@ func NewCallbackCDecl(fn interface{}) uintptr {
 //sys	SetConsoleOutputCP(cp uint32) (err error) = kernel32.SetConsoleOutputCP
 //sys	WriteConsole(console Handle, buf *uint16, towrite uint32, written *uint32, reserved *byte) (err error) = kernel32.WriteConsoleW
 //sys	ReadConsole(console Handle, buf *uint16, toread uint32, read *uint32, inputControl *byte) (err error) = kernel32.ReadConsoleW
+//sys	ReadConsoleInput(console Handle, buf *InputRecord, toread uint32, read *uint32) (err error) = kernel32.ReadConsoleInputW
+//sys	PeekConsoleInput(console Handle, buf *InputRecord, toread uint32, read *uint32) (err error) = kernel32.PeekConsoleInputW
+//sys	GetNumberOfConsoleInputEvents(console Handle, numevents *uint32) (err error) = kernel32.GetNumberOfConsoleInputEvents
+//sys	FlushConsoleInputBuffer(console Handle) (err error) = kernel32.FlushConsoleInputBuffer
 //sys	resizePseudoConsole(pconsole Handle, size uint32) (hr error) = kernel32.ResizePseudoConsole
 //sys	CreateToolhelp32Snapshot(flags uint32, processId uint32) (handle Handle, err error) [failretval==InvalidHandle] = kernel32.CreateToolhelp32Snapshot
 //sys	Module32First(snapshot Handle, moduleEntry *ModuleEntry32) (err error) = kernel32.Module32FirstW

windows/types_windows.go

@@ -3474,3 +3474,90 @@ const (
 	KLF_NOTELLSHELL   = 0x00000080
 	KLF_SETFORPROCESS = 0x00000100
 )
+
+// FocusEventRecord corresponds to the FocusEventRecord structure from the
+// Windows console API.
+// https://docs.microsoft.com/en-us/windows/console/focus-event-record-str
+type FocusEventRecord struct {
+	// SetFocus is reserved and should not be used.
+	SetFocus bool
+}
+
+// KeyEventRecord corresponds to the KeyEventRecord structure from the Windows
+// console API.
+// https://docs.microsoft.com/en-us/windows/console/key-event-record-str
+type KeyEventRecord struct {
+	// KeyDown specified whether the key is pressed or released.
+	KeyDown bool
+
+	//  RepeatCount indicates that a key is being held down. For example, when a
+	//  key is held down, five events with RepeatCount equal to 1 may be
+	//  generated, one event with RepeatCount equal to 5, or multiple events
+	//  with RepeatCount greater than or equal to 1.
+	RepeatCount uint16
+
+	// VirtualKeyCode identifies the given key in a device-independent manner
+	// (see
+	// https://docs.microsoft.com/en-us/windows/win32/inputdev/virtual-key-codes).
+	VirtualKeyCode uint16
+
+	//  VirtualScanCode represents the device-dependent value generated by the
+	//  keyboard hardware.
+	VirtualScanCode uint16
+
+	// Char is the character that corresponds to the pressed key. Char can be
+	// zero for some keys.
+	Char rune
+
+	//ControlKeyState holds the state of the control keys.
+	ControlKeyState uint32
+}
+
+// MenuEventRecord corresponds to the MenuEventRecord structure from the
+// Windows console API.
+// https://docs.microsoft.com/en-us/windows/console/menu-event-record-str
+type MenuEventRecord struct {
+	CommandID uint32
+}
+
+// MouseEventRecord corresponds to the MouseEventRecord structure from the
+// Windows console API.
+// https://docs.microsoft.com/en-us/windows/console/mouse-event-record-str
+type MouseEventRecord struct {
+	// MousePosition contains the location of the cursor, in terms of the
+	// console screen buffer's character-cell coordinates.
+	MousePositon Coord
+
+	// ButtonState holds the status of the mouse buttons.
+	ButtonState uint32
+
+	// ControlKeyState holds the state of the control keys.
+	ControlKeyState uint32
+
+	// EventFlags specify the type of mouse event.
+	EventFlags uint32
+}
+
+// WindowBufferSizeRecord corresponds to the WindowBufferSizeRecord structure
+// from the Windows console API.
+// https://docs.microsoft.com/en-us/windows/console/window-buffer-size-record-str
+type WindowBufferSizeRecord struct {
+	// Size contains the size of the console screen buffer, in character cell
+	// columns and rows.
+	Size Coord
+}
+
+// InputRecord corresponds to the INPUT_RECORD structure from the Windows
+// console API.
+//
+// https://docs.microsoft.com/en-us/windows/console/input-record-str
+type InputRecord struct {
+	// EventType specifies the type of event that helt in Event.
+	EventType uint16
+
+	// Padding of the 16-bit EventType to a whole 32-bit dword.
+	_ [2]byte
+
+	// Event holds the actual event data.
+	Event [16]byte
+}