terminal/src/terminal/parser/InputStateMachineEngine.cpp
Mike Griese 94bcbb9204
The InputStateMachine should dispatch Intermediate characters (#1267)
The OutputStateMachine needs to collect "Intermediate" characters to be able to call [`Designate G0 Character Set`](https://invisible-island.net/xterm/ctlseqs/ctlseqs.html#h2-Controls-beginning-with-ESC) (as well as other sequences we don't yet support).

However, the InputStateMachine used by conpty to process input should _not_ collect these characters. The input engine uses `\x1b` as an indicator that a key was pressed with `Alt`. For keys like `/`, we want to dispatch the key immediately, instead of collecting it and leaving us in the Escape state.
2019-06-14 14:48:12 -05:00

986 lines
36 KiB
C++

// Copyright (c) Microsoft Corporation.
// Licensed under the MIT license.
#include "precomp.h"
#include "stateMachine.hpp"
#include "InputStateMachineEngine.hpp"
#include "../../inc/unicode.hpp"
#include "ascii.hpp"
#ifdef BUILD_ONECORE_INTERACTIVITY
#include "../../interactivity/inc/VtApiRedirection.hpp"
#endif
using namespace Microsoft::Console::VirtualTerminal;
// The values used by VkKeyScan to encode modifiers in the high order byte
const short KEYSCAN_SHIFT = 1;
const short KEYSCAN_CTRL = 2;
const short KEYSCAN_ALT = 4;
// The values with which VT encodes modifier values.
const short VT_SHIFT = 1;
const short VT_ALT = 2;
const short VT_CTRL = 4;
const size_t WRAPPED_SEQUENCE_MAX_LENGTH = 8;
// For reference, the equivalent INPUT_RECORD values are:
// RIGHT_ALT_PRESSED 0x0001
// LEFT_ALT_PRESSED 0x0002
// RIGHT_CTRL_PRESSED 0x0004
// LEFT_CTRL_PRESSED 0x0008
// SHIFT_PRESSED 0x0010
// NUMLOCK_ON 0x0020
// SCROLLLOCK_ON 0x0040
// CAPSLOCK_ON 0x0080
// ENHANCED_KEY 0x0100
const InputStateMachineEngine::CSI_TO_VKEY InputStateMachineEngine::s_rgCsiMap[]{
{ CsiActionCodes::ArrowUp, VK_UP },
{ CsiActionCodes::ArrowDown, VK_DOWN },
{ CsiActionCodes::ArrowRight, VK_RIGHT },
{ CsiActionCodes::ArrowLeft, VK_LEFT },
{ CsiActionCodes::Home, VK_HOME },
{ CsiActionCodes::End, VK_END },
{ CsiActionCodes::CSI_F1, VK_F1 },
{ CsiActionCodes::CSI_F2, VK_F2 },
{ CsiActionCodes::CSI_F3, VK_F3 },
{ CsiActionCodes::CSI_F4, VK_F4 },
};
const InputStateMachineEngine::GENERIC_TO_VKEY InputStateMachineEngine::s_rgGenericMap[]{
{ GenericKeyIdentifiers::GenericHome, VK_HOME },
{ GenericKeyIdentifiers::Insert, VK_INSERT },
{ GenericKeyIdentifiers::Delete, VK_DELETE },
{ GenericKeyIdentifiers::GenericEnd, VK_END },
{ GenericKeyIdentifiers::Prior, VK_PRIOR },
{ GenericKeyIdentifiers::Next, VK_NEXT },
{ GenericKeyIdentifiers::F5, VK_F5 },
{ GenericKeyIdentifiers::F6, VK_F6 },
{ GenericKeyIdentifiers::F7, VK_F7 },
{ GenericKeyIdentifiers::F8, VK_F8 },
{ GenericKeyIdentifiers::F9, VK_F9 },
{ GenericKeyIdentifiers::F10, VK_F10 },
{ GenericKeyIdentifiers::F11, VK_F11 },
{ GenericKeyIdentifiers::F12, VK_F12 },
};
const InputStateMachineEngine::SS3_TO_VKEY InputStateMachineEngine::s_rgSs3Map[]{
{ Ss3ActionCodes::SS3_F1, VK_F1 },
{ Ss3ActionCodes::SS3_F2, VK_F2 },
{ Ss3ActionCodes::SS3_F3, VK_F3 },
{ Ss3ActionCodes::SS3_F4, VK_F4 },
};
InputStateMachineEngine::InputStateMachineEngine(IInteractDispatch* const pDispatch) :
InputStateMachineEngine(pDispatch, false)
{
}
InputStateMachineEngine::InputStateMachineEngine(IInteractDispatch* const pDispatch, const bool lookingForDSR) :
_pDispatch(THROW_IF_NULL_ALLOC(pDispatch)),
_lookingForDSR(lookingForDSR)
{
}
// Method Description:
// - Triggers the Execute action to indicate that the listener should
// immediately respond to a C0 control character.
// Arguments:
// - wch - Character to dispatch.
// Return Value:
// - true iff we successfully dispatched the sequence.
bool InputStateMachineEngine::ActionExecute(const wchar_t wch)
{
return _DoControlCharacter(wch, false);
}
bool InputStateMachineEngine::_DoControlCharacter(const wchar_t wch, const bool writeAlt)
{
bool fSuccess = false;
if (wch == UNICODE_ETX && !writeAlt)
{
// This is Ctrl+C, which is handled specially by the host.
fSuccess = _pDispatch->WriteCtrlC();
}
else if (wch >= '\x0' && wch < '\x20')
{
// This is a C0 Control Character.
// This should be translated as Ctrl+(wch+x40)
wchar_t actualChar = wch;
bool writeCtrl = true;
short vkey = 0;
DWORD dwModifierState = 0;
switch (wch)
{
case L'\b':
fSuccess = _GenerateKeyFromChar(wch + 0x40, &vkey, nullptr);
break;
case L'\r':
writeCtrl = false;
fSuccess = _GenerateKeyFromChar(wch, &vkey, nullptr);
break;
case L'\x1b':
// Translate escape as the ESC key, NOT C-[.
// This means that C-[ won't insert ^[ into the buffer anymore,
// which isn't the worst tradeoff.
vkey = VK_ESCAPE;
writeCtrl = false;
fSuccess = true;
break;
case L'\t':
writeCtrl = false;
fSuccess = _GenerateKeyFromChar(actualChar, &vkey, &dwModifierState);
break;
default:
fSuccess = _GenerateKeyFromChar(actualChar, &vkey, &dwModifierState);
break;
}
if (fSuccess)
{
if (writeCtrl)
{
WI_SetFlag(dwModifierState, LEFT_CTRL_PRESSED);
}
if (writeAlt)
{
WI_SetFlag(dwModifierState, LEFT_ALT_PRESSED);
}
fSuccess = _WriteSingleKey(actualChar, vkey, dwModifierState);
}
}
else if (wch == '\x7f')
{
// Note:
// The windows telnet expects to send x7f as DELETE, not backspace.
// However, the windows telnetd also wouldn't let you move the
// cursor back into the input line, so it wasn't possible to
// "delete" any input at all, only backspace.
// Because of this, we're treating x7f as backspace, like most
// terminals do.
fSuccess = _WriteSingleKey('\x8', VK_BACK, writeAlt ? LEFT_ALT_PRESSED : 0);
}
else
{
fSuccess = ActionPrint(wch);
}
return fSuccess;
}
// Routine Description:
// - Triggers the Execute action to indicate that the listener should
// immediately respond to a C0 control character.
// This is called from the Escape state in the state machine, indicating the
// immediately previous character was an 0x1b.
// We need to override this method to properly treat 0x1b + C0 strings as
// Ctrl+Alt+<char> input sequences.
// Arguments:
// - wch - Character to dispatch.
// Return Value:
// - true iff we successfully dispatched the sequence.
bool InputStateMachineEngine::ActionExecuteFromEscape(const wchar_t wch)
{
return _DoControlCharacter(wch, true);
}
// Method Description:
// - Triggers the Print action to indicate that the listener should render the
// character given.
// Arguments:
// - wch - Character to dispatch.
// Return Value:
// - true iff we successfully dispatched the sequence.
bool InputStateMachineEngine::ActionPrint(const wchar_t wch)
{
short vkey = 0;
DWORD dwModifierState = 0;
bool fSuccess = _GenerateKeyFromChar(wch, &vkey, &dwModifierState);
if (fSuccess)
{
fSuccess = _WriteSingleKey(wch, vkey, dwModifierState);
}
return fSuccess;
}
// Method Description:
// - Triggers the Print action to indicate that the listener should render the
// string of characters given.
// Arguments:
// - rgwch - string to dispatch.
// - cch - length of rgwch
// Return Value:
// - true iff we successfully dispatched the sequence.
bool InputStateMachineEngine::ActionPrintString(const wchar_t* const rgwch,
const size_t cch)
{
if (cch == 0)
{
return true;
}
return _pDispatch->WriteString(rgwch, cch);
}
// Method Description:
// - Triggers the Print action to indicate that the listener should render the
// string of characters given.
// Arguments:
// - rgwch - string to dispatch.
// - cch - length of rgwch
// Return Value:
// - true iff we successfully dispatched the sequence.
bool InputStateMachineEngine::ActionPassThroughString(const wchar_t* const rgwch,
_In_ size_t const cch)
{
return ActionPrintString(rgwch, cch);
}
// Method Description:
// - Triggers the EscDispatch action to indicate that the listener should handle
// a simple escape sequence. These sequences traditionally start with ESC
// and a simple letter. No complicated parameters.
// Arguments:
// - wch - Character to dispatch.
// - cIntermediate - Number of "Intermediate" characters found - such as '!', '?'
// - wchIntermediate - Intermediate character in the sequence, if there was one.
// Return Value:
// - true iff we successfully dispatched the sequence.
bool InputStateMachineEngine::ActionEscDispatch(const wchar_t wch,
const unsigned short /*cIntermediate*/,
const wchar_t /*wchIntermediate*/)
{
bool fSuccess = false;
// 0x7f is DEL, which we treat effectively the same as a ctrl character.
if (wch == 0x7f)
{
fSuccess = _DoControlCharacter(wch, true);
}
else
{
DWORD dwModifierState = 0;
short vk = 0;
fSuccess = _GenerateKeyFromChar(wch, &vk, &dwModifierState);
if (fSuccess)
{
// Alt is definitely pressed in the esc+key case.
dwModifierState = WI_SetFlag(dwModifierState, LEFT_ALT_PRESSED);
fSuccess = _WriteSingleKey(wch, vk, dwModifierState);
}
}
return fSuccess;
}
// Method Description:
// - Triggers the CsiDispatch action to indicate that the listener should handle
// a control sequence. These sequences perform various API-type commands
// that can include many parameters.
// Arguments:
// - wch - Character to dispatch.
// - cIntermediate - Number of "Intermediate" characters found - such as '!', '?'
// - wchIntermediate - Intermediate character in the sequence, if there was one.
// - rgusParams - set of numeric parameters collected while pasring the sequence.
// - cParams - number of parameters found.
// Return Value:
// - true iff we successfully dispatched the sequence.
bool InputStateMachineEngine::ActionCsiDispatch(const wchar_t wch,
const unsigned short /*cIntermediate*/,
const wchar_t /*wchIntermediate*/,
_In_reads_(cParams) const unsigned short* const rgusParams,
const unsigned short cParams)
{
DWORD dwModifierState = 0;
short vkey = 0;
unsigned int uiFunction = 0;
unsigned int col = 0;
unsigned int row = 0;
// This is all the args after the first arg, and the count of args not including the first one.
const unsigned short* const rgusRemainingArgs = (cParams > 1) ? rgusParams + 1 : rgusParams;
const unsigned short cRemainingArgs = (cParams >= 1) ? cParams - 1 : 0;
bool fSuccess = false;
switch (wch)
{
case CsiActionCodes::Generic:
dwModifierState = _GetGenericKeysModifierState(rgusParams, cParams);
fSuccess = _GetGenericVkey(rgusParams, cParams, &vkey);
break;
// case CsiActionCodes::DSR_DeviceStatusReportResponse:
case CsiActionCodes::CSI_F3:
// The F3 case is special - it shares a code with the DeviceStatusResponse.
// If we're looking for that response, then do that, and break out.
// Else, fall though to the _GetCursorKeysModifierState handler.
if (_lookingForDSR)
{
fSuccess = true;
fSuccess = _GetXYPosition(rgusParams, cParams, &row, &col);
break;
}
case CsiActionCodes::ArrowUp:
case CsiActionCodes::ArrowDown:
case CsiActionCodes::ArrowRight:
case CsiActionCodes::ArrowLeft:
case CsiActionCodes::Home:
case CsiActionCodes::End:
case CsiActionCodes::CSI_F1:
case CsiActionCodes::CSI_F2:
case CsiActionCodes::CSI_F4:
dwModifierState = _GetCursorKeysModifierState(rgusParams, cParams);
fSuccess = _GetCursorKeysVkey(wch, &vkey);
break;
case CsiActionCodes::CursorBackTab:
dwModifierState = SHIFT_PRESSED;
vkey = VK_TAB;
fSuccess = true;
break;
case CsiActionCodes::DTTERM_WindowManipulation:
fSuccess = _GetWindowManipulationType(rgusParams,
cParams,
&uiFunction);
break;
default:
fSuccess = false;
break;
}
if (fSuccess)
{
switch (wch)
{
// case CsiActionCodes::DSR_DeviceStatusReportResponse:
case CsiActionCodes::CSI_F3:
// The F3 case is special - it shares a code with the DeviceStatusResponse.
// If we're looking for that response, then do that, and break out.
// Else, fall though to the _GetCursorKeysModifierState handler.
if (_lookingForDSR)
{
fSuccess = _pDispatch->MoveCursor(row, col);
// Right now we're only looking for on initial cursor
// position response. After that, only look for F3.
_lookingForDSR = false;
break;
}
__fallthrough;
case CsiActionCodes::Generic:
case CsiActionCodes::ArrowUp:
case CsiActionCodes::ArrowDown:
case CsiActionCodes::ArrowRight:
case CsiActionCodes::ArrowLeft:
case CsiActionCodes::Home:
case CsiActionCodes::End:
case CsiActionCodes::CSI_F1:
case CsiActionCodes::CSI_F2:
case CsiActionCodes::CSI_F4:
case CsiActionCodes::CursorBackTab:
fSuccess = _WriteSingleKey(vkey, dwModifierState);
break;
case CsiActionCodes::DTTERM_WindowManipulation:
fSuccess = _pDispatch->WindowManipulation(static_cast<DispatchTypes::WindowManipulationType>(uiFunction),
rgusRemainingArgs,
cRemainingArgs);
break;
default:
fSuccess = false;
break;
}
}
return fSuccess;
}
// Routine Description:
// - Triggers the Ss3Dispatch action to indicate that the listener should handle
// a control sequence. These sequences perform various API-type commands
// that can include many parameters.
// Arguments:
// - wch - Character to dispatch.
// - rgusParams - set of numeric parameters collected while pasring the sequence.
// - cParams - number of parameters found.
// Return Value:
// - true iff we successfully dispatched the sequence.
bool InputStateMachineEngine::ActionSs3Dispatch(const wchar_t wch,
_In_reads_(_Param_(3)) const unsigned short* const /*rgusParams*/,
const unsigned short /*cParams*/)
{
// Ss3 sequence keys aren't modified.
// When F1-F4 *are* modified, they're sent as CSI sequences, not SS3's.
DWORD dwModifierState = 0;
short vkey = 0;
bool fSuccess = _GetSs3KeysVkey(wch, &vkey);
if (fSuccess)
{
fSuccess = _WriteSingleKey(vkey, dwModifierState);
}
return fSuccess;
}
// Method Description:
// - Triggers the Clear action to indicate that the state machine should erase
// all internal state.
// Arguments:
// - <none>
// Return Value:
// - true iff we successfully dispatched the sequence.
bool InputStateMachineEngine::ActionClear()
{
return true;
}
// Method Description:
// - Triggers the Ignore action to indicate that the state machine should eat
// this character and say nothing.
// Arguments:
// - <none>
// Return Value:
// - true iff we successfully dispatched the sequence.
bool InputStateMachineEngine::ActionIgnore()
{
return true;
}
// Method Description:
// - Triggers the OscDispatch action to indicate that the listener should handle a control sequence.
// These sequences perform various API-type commands that can include many parameters.
// Arguments:
// - wch - Character to dispatch. This will be a BEL or ST char.
// - sOscParam - identifier of the OSC action to perform
// - pwchOscStringBuffer - OSC string we've collected. NOT null terminated.
// - cchOscString - length of pwchOscStringBuffer
// Return Value:
// - true if we handled the dsipatch.
bool InputStateMachineEngine::ActionOscDispatch(const wchar_t /*wch*/,
const unsigned short /*sOscParam*/,
_Inout_updates_(_Param_(4)) wchar_t* const /*pwchOscStringBuffer*/,
const unsigned short /*cchOscString*/)
{
return false;
}
// Method Description:
// - Writes a sequence of keypresses to the buffer based on the wch,
// vkey and modifiers passed in. Will create both the appropriate key downs
// and ups for that key for writing to the input. Will also generate
// keypresses for pressing the modifier keys while typing that character.
// If rgInput isn't big enough, then it will stop writing when it's filled.
// Arguments:
// - wch - the character to write to the input callback.
// - vkey - the VKEY of the key to write to the input callback.
// - dwModifierState - the modifier state to write with the key.
// - rgInput - the buffer of characters to write the keypresses to. Can write
// up to 8 records to this buffer.
// - cInput - the size of rgInput. This should be at least WRAPPED_SEQUENCE_MAX_LENGTH
// Return Value:
// - the number of records written, or 0 if the buffer wasn't big enough.
size_t InputStateMachineEngine::_GenerateWrappedSequence(const wchar_t wch,
const short vkey,
const DWORD dwModifierState,
_Inout_updates_(cInput) INPUT_RECORD* rgInput,
const size_t cInput)
{
// TODO: Reuse the clipboard functions for generating input for characters
// that aren't on the current keyboard.
// MSFT:13994942
if (cInput < WRAPPED_SEQUENCE_MAX_LENGTH)
{
return 0;
}
const bool fShift = WI_IsFlagSet(dwModifierState, SHIFT_PRESSED);
const bool fCtrl = WI_IsFlagSet(dwModifierState, LEFT_CTRL_PRESSED);
const bool fAlt = WI_IsFlagSet(dwModifierState, LEFT_ALT_PRESSED);
size_t index = 0;
INPUT_RECORD* next = &rgInput[0];
DWORD dwCurrentModifiers = 0;
if (fShift)
{
WI_SetFlag(dwCurrentModifiers, SHIFT_PRESSED);
next->EventType = KEY_EVENT;
next->Event.KeyEvent.bKeyDown = TRUE;
next->Event.KeyEvent.dwControlKeyState = dwCurrentModifiers;
next->Event.KeyEvent.wRepeatCount = 1;
next->Event.KeyEvent.wVirtualKeyCode = VK_SHIFT;
next->Event.KeyEvent.wVirtualScanCode = static_cast<WORD>(MapVirtualKey(VK_SHIFT, MAPVK_VK_TO_VSC));
next->Event.KeyEvent.uChar.UnicodeChar = 0x0;
next++;
index++;
}
if (fAlt)
{
WI_SetFlag(dwCurrentModifiers, LEFT_ALT_PRESSED);
next->EventType = KEY_EVENT;
next->Event.KeyEvent.bKeyDown = TRUE;
next->Event.KeyEvent.dwControlKeyState = dwCurrentModifiers;
next->Event.KeyEvent.wRepeatCount = 1;
next->Event.KeyEvent.wVirtualKeyCode = VK_MENU;
next->Event.KeyEvent.wVirtualScanCode = static_cast<WORD>(MapVirtualKey(VK_MENU, MAPVK_VK_TO_VSC));
next->Event.KeyEvent.uChar.UnicodeChar = 0x0;
next++;
index++;
}
if (fCtrl)
{
WI_SetFlag(dwCurrentModifiers, LEFT_CTRL_PRESSED);
next->EventType = KEY_EVENT;
next->Event.KeyEvent.bKeyDown = TRUE;
next->Event.KeyEvent.dwControlKeyState = dwCurrentModifiers;
next->Event.KeyEvent.wRepeatCount = 1;
next->Event.KeyEvent.wVirtualKeyCode = VK_CONTROL;
next->Event.KeyEvent.wVirtualScanCode = static_cast<WORD>(MapVirtualKey(VK_CONTROL, MAPVK_VK_TO_VSC));
next->Event.KeyEvent.uChar.UnicodeChar = 0x0;
next++;
index++;
}
size_t added = _GetSingleKeypress(wch, vkey, dwCurrentModifiers, next, cInput - index);
// if _GetSingleKeypress added more than two events we might overflow the buffer
if (added > 2)
{
return index;
}
next += added;
index += added;
if (fCtrl)
{
WI_ClearFlag(dwCurrentModifiers, LEFT_CTRL_PRESSED);
next->EventType = KEY_EVENT;
next->Event.KeyEvent.bKeyDown = FALSE;
next->Event.KeyEvent.dwControlKeyState = dwCurrentModifiers;
next->Event.KeyEvent.wRepeatCount = 1;
next->Event.KeyEvent.wVirtualKeyCode = VK_CONTROL;
next->Event.KeyEvent.wVirtualScanCode = static_cast<WORD>(MapVirtualKey(VK_CONTROL, MAPVK_VK_TO_VSC));
next->Event.KeyEvent.uChar.UnicodeChar = 0x0;
next++;
index++;
}
if (fAlt)
{
WI_ClearFlag(dwCurrentModifiers, LEFT_ALT_PRESSED);
next->EventType = KEY_EVENT;
next->Event.KeyEvent.bKeyDown = FALSE;
next->Event.KeyEvent.dwControlKeyState = dwCurrentModifiers;
next->Event.KeyEvent.wRepeatCount = 1;
next->Event.KeyEvent.wVirtualKeyCode = VK_MENU;
next->Event.KeyEvent.wVirtualScanCode = static_cast<WORD>(MapVirtualKey(VK_MENU, MAPVK_VK_TO_VSC));
next->Event.KeyEvent.uChar.UnicodeChar = 0x0;
next++;
index++;
}
if (fShift)
{
WI_ClearFlag(dwCurrentModifiers, SHIFT_PRESSED);
next->EventType = KEY_EVENT;
next->Event.KeyEvent.bKeyDown = FALSE;
next->Event.KeyEvent.dwControlKeyState = dwCurrentModifiers;
next->Event.KeyEvent.wRepeatCount = 1;
next->Event.KeyEvent.wVirtualKeyCode = VK_SHIFT;
next->Event.KeyEvent.wVirtualScanCode = static_cast<WORD>(MapVirtualKey(VK_SHIFT, MAPVK_VK_TO_VSC));
next->Event.KeyEvent.uChar.UnicodeChar = 0x0;
next++;
index++;
}
return index;
}
// Method Description:
// - Writes a single character keypress to the input buffer. This writes both
// the keydown and keyup events.
// Arguments:
// - wch - the character to write to the buffer.
// - vkey - the VKEY of the key to write to the buffer.
// - dwModifierState - the modifier state to write with the key.
// - rgInput - the buffer of characters to write the keypress to. Will always
// write to the first two positions in the buffer.
// - cRecords - the size of rgInput
// Return Value:
// - the number of input records written.
size_t InputStateMachineEngine::_GetSingleKeypress(const wchar_t wch,
const short vkey,
const DWORD dwModifierState,
_Inout_updates_(cRecords) INPUT_RECORD* const rgInput,
const size_t cRecords)
{
FAIL_FAST_IF(!(cRecords >= 2));
if (cRecords < 2)
{
return 0;
}
rgInput[0].EventType = KEY_EVENT;
rgInput[0].Event.KeyEvent.bKeyDown = TRUE;
rgInput[0].Event.KeyEvent.dwControlKeyState = dwModifierState;
rgInput[0].Event.KeyEvent.wRepeatCount = 1;
rgInput[0].Event.KeyEvent.wVirtualKeyCode = vkey;
rgInput[0].Event.KeyEvent.wVirtualScanCode = (WORD)MapVirtualKey(vkey, MAPVK_VK_TO_VSC);
rgInput[0].Event.KeyEvent.uChar.UnicodeChar = wch;
rgInput[1] = rgInput[0];
rgInput[1].Event.KeyEvent.bKeyDown = FALSE;
return 2;
}
// Method Description:
// - Writes a sequence of keypresses to the input callback based on the wch,
// vkey and modifiers passed in. Will create both the appropriate key downs
// and ups for that key for writing to the input. Will also generate
// keypresses for pressing the modifier keys while typing that character.
// Arguments:
// - wch - the character to write to the input callback.
// - vkey - the VKEY of the key to write to the input callback.
// - dwModifierState - the modifier state to write with the key.
// Return Value:
// - true iff we successfully wrote the keypress to the input callback.
bool InputStateMachineEngine::_WriteSingleKey(const wchar_t wch, const short vkey, const DWORD dwModifierState)
{
// At most 8 records - 2 for each of shift,ctrl,alt up and down, and 2 for the actual key up and down.
INPUT_RECORD rgInput[WRAPPED_SEQUENCE_MAX_LENGTH];
size_t cInput = _GenerateWrappedSequence(wch, vkey, dwModifierState, rgInput, WRAPPED_SEQUENCE_MAX_LENGTH);
std::deque<std::unique_ptr<IInputEvent>> inputEvents = IInputEvent::Create(gsl::make_span(rgInput, cInput));
return _pDispatch->WriteInput(inputEvents);
}
// Method Description:
// - Helper for writing a single key to the input when you only know the vkey.
// Will automatically get the wchar_t associated with that vkey.
// Arguments:
// - vkey - the VKEY of the key to write to the input callback.
// - dwModifierState - the modifier state to write with the key.
// Return Value:
// - true iff we successfully wrote the keypress to the input callback.
bool InputStateMachineEngine::_WriteSingleKey(const short vkey, const DWORD dwModifierState)
{
wchar_t wch = (wchar_t)MapVirtualKey(vkey, MAPVK_VK_TO_CHAR);
return _WriteSingleKey(wch, vkey, dwModifierState);
}
// Method Description:
// - Retrieves the modifier state from a set of parameters for a cursor keys
// sequence. This is for Arrow keys, Home, End, etc.
// Arguments:
// - rgusParams - the set of parameters to get the modifier state from.
// - cParams - the number of elements in rgusParams
// Return Value:
// - the INPUT_RECORD comaptible modifier state.
DWORD InputStateMachineEngine::_GetCursorKeysModifierState(_In_reads_(cParams) const unsigned short* const rgusParams, const unsigned short cParams)
{
// Both Cursor keys and generic keys keep their modifiers in the same index.
return _GetGenericKeysModifierState(rgusParams, cParams);
}
// Method Description:
// - Retrieves the modifier state from a set of parameters for a "Generic"
// keypress - one who's sequence is terminated with a '~'.
// Arguments:
// - rgusParams - the set of parameters to get the modifier state from.
// - cParams - the number of elements in rgusParams
// Return Value:
// - the INPUT_RECORD compatible modifier state.
DWORD InputStateMachineEngine::_GetGenericKeysModifierState(_In_reads_(cParams) const unsigned short* const rgusParams, const unsigned short cParams)
{
DWORD dwModifiers = 0;
if (_IsModified(cParams) && cParams >= 2)
{
dwModifiers = _GetModifier(rgusParams[1]);
}
return dwModifiers;
}
// Method Description:
// - Determines if a set of parameters indicates a modified keypress
// Arguments:
// - cParams - the nummber of parameters we've collected in this sequence
// Return Value:
// - true iff the sequence is a modified sequence.
bool InputStateMachineEngine::_IsModified(const unsigned short cParams)
{
// modified input either looks like
// \x1b[1;mA or \x1b[17;m~
// Both have two parameters
return cParams == 2;
}
// Method Description:
// - Converts a VT encoded modifier param into a INPUT_RECORD compatible one.
// Arguments:
// - modifierParam - the VT modifier value to convert
// Return Value:
// - The equivalent INPUT_RECORD modifier value.
DWORD InputStateMachineEngine::_GetModifier(const unsigned short modifierParam)
{
// VT Modifiers are 1+(modifier flags)
unsigned short vtParam = modifierParam - 1;
DWORD modifierState = modifierParam > 0 ? ENHANCED_KEY : 0;
bool fShift = WI_IsFlagSet(vtParam, VT_SHIFT);
bool fAlt = WI_IsFlagSet(vtParam, VT_ALT);
bool fCtrl = WI_IsFlagSet(vtParam, VT_CTRL);
return modifierState | (fShift ? SHIFT_PRESSED : 0) | (fAlt ? LEFT_ALT_PRESSED : 0) | (fCtrl ? LEFT_CTRL_PRESSED : 0);
}
// Method Description:
// - Gets the Vkey form the generic keys table associated with a particular
// identifier code. The identifier code will be the first param in rgusParams.
// Arguments:
// - rgusParams: an array of shorts where the first is the identifier of the key
// we're looking for.
// - cParams: number of params in rgusParams
// - pVkey: Recieves the vkey
// Return Value:
// true iff we found the key
bool InputStateMachineEngine::_GetGenericVkey(_In_reads_(cParams) const unsigned short* const rgusParams, const unsigned short cParams, _Out_ short* const pVkey) const
{
*pVkey = 0;
if (cParams < 1)
{
return false;
}
const unsigned short identifier = rgusParams[0];
for (int i = 0; i < ARRAYSIZE(s_rgGenericMap); i++)
{
GENERIC_TO_VKEY mapping = s_rgGenericMap[i];
if (mapping.Identifier == identifier)
{
*pVkey = mapping.vkey;
return true;
}
}
return false;
}
// Method Description:
// - Gets the Vkey from the CSI codes table associated with a particular character.
// Arguments:
// - wch: the wchar_t to get the mapped vkey of.
// - pVkey: Recieves the vkey
// Return Value:
// true iff we found the key
bool InputStateMachineEngine::_GetCursorKeysVkey(const wchar_t wch, _Out_ short* const pVkey) const
{
*pVkey = 0;
for (int i = 0; i < ARRAYSIZE(s_rgCsiMap); i++)
{
CSI_TO_VKEY mapping = s_rgCsiMap[i];
if (mapping.Action == wch)
{
*pVkey = mapping.vkey;
return true;
}
}
return false;
}
// Method Description:
// - Gets the Vkey from the SS3 codes table associated with a particular character.
// Arguments:
// - wch: the wchar_t to get the mapped vkey of.
// - pVkey: Recieves the vkey
// Return Value:
// true iff we found the key
bool InputStateMachineEngine::_GetSs3KeysVkey(const wchar_t wch, _Out_ short* const pVkey) const
{
*pVkey = 0;
for (int i = 0; i < ARRAYSIZE(s_rgSs3Map); i++)
{
SS3_TO_VKEY mapping = s_rgSs3Map[i];
if (mapping.Action == wch)
{
*pVkey = mapping.vkey;
return true;
}
}
return false;
}
// Method Description:
// - Gets the Vkey and modifier state that's associated with a particular char.
// Arguments:
// - wch: the wchar_t to get the vkey and modifier state of.
// - pVkey: Recieves the vkey
// - pdwModifierState: Recieves the modifier state
// Return Value:
// <none>
bool InputStateMachineEngine::_GenerateKeyFromChar(const wchar_t wch,
_Out_ short* const pVkey,
_Out_ DWORD* const pdwModifierState)
{
// Low order byte is key, high order is modifiers
short keyscan = VkKeyScanW(wch);
short vkey = LOBYTE(keyscan);
short keyscanModifiers = HIBYTE(keyscan);
if (vkey == -1 && keyscanModifiers == -1)
{
return false;
}
// Because of course, these are not the same flags.
short dwModifierState = 0 |
(WI_IsFlagSet(keyscanModifiers, KEYSCAN_SHIFT) ? SHIFT_PRESSED : 0) |
(WI_IsFlagSet(keyscanModifiers, KEYSCAN_CTRL) ? LEFT_CTRL_PRESSED : 0) |
(WI_IsFlagSet(keyscanModifiers, KEYSCAN_ALT) ? LEFT_ALT_PRESSED : 0);
if (pVkey != nullptr)
{
*pVkey = vkey;
}
if (pdwModifierState != nullptr)
{
*pdwModifierState = dwModifierState;
}
return true;
}
// Method Description:
// - Returns true if the engine should dispatch on the last charater of a string
// always, even if the sequence hasn't normally dispatched.
// If this is false, the engine will persist its state across calls to
// ProcessString, and dispatch only at the end of the sequence.
// Return Value:
// - True iff we should manually dispatch on the last character of a string.
bool InputStateMachineEngine::FlushAtEndOfString() const
{
return true;
}
// Routine Description:
// - Returns true if the engine should dispatch control characters in the Escape
// state. Typically, control characters are immediately executed in the
// Escape state without returning to ground. If this returns true, the
// state machine will instead call ActionExecuteFromEscape and then enter
// the Ground state when a control character is encountered in the escape
// state.
// Return Value:
// - True iff we should return to the Ground state when the state machine
// encounters a Control (C0) character in the Escape state.
bool InputStateMachineEngine::DispatchControlCharsFromEscape() const
{
return true;
}
// Routine Description:
// - Returns false if the engine wants to be able to collect intermediate
// characters in the Escape state. We do _not_ want to buffer any characters
// as intermediates, because we use ESC as a prefix to indicate a key was
// pressed while Alt was pressed.
// Return Value:
// - True iff we should dispatch in the Escape state when we encounter a
// Intermediate character.
bool InputStateMachineEngine::DispatchIntermediatesFromEscape() const
{
return true;
}
// Method Description:
// - Retrieves the type of window manipulation operation from the parameter pool
// stored during Param actions.
// This is kept seperate from the output version, as there may be
// codes that are supported in one direction but not the other.
// Arguments:
// - rgusParams - Array of parameters collected
// - cParams - Number of parameters we've collected
// - puiFunction - Memory location to receive the function type
// Return Value:
// - True iff we successfully pulled the function type from the parameters
bool InputStateMachineEngine::_GetWindowManipulationType(_In_reads_(cParams) const unsigned short* const rgusParams,
const unsigned short cParams,
_Out_ unsigned int* const puiFunction) const
{
bool fSuccess = false;
*puiFunction = DispatchTypes::WindowManipulationType::Invalid;
if (cParams > 0)
{
switch (rgusParams[0])
{
case DispatchTypes::WindowManipulationType::RefreshWindow:
*puiFunction = DispatchTypes::WindowManipulationType::RefreshWindow;
fSuccess = true;
break;
case DispatchTypes::WindowManipulationType::ResizeWindowInCharacters:
*puiFunction = DispatchTypes::WindowManipulationType::ResizeWindowInCharacters;
fSuccess = true;
break;
default:
fSuccess = false;
}
}
return fSuccess;
}
// Routine Description:
// - Retrieves an X/Y coordinate pair for a cursor operation from the parameter pool stored during Param actions.
// Arguments:
// - puiLine - Memory location to receive the Y/Line/Row position
// - puiColumn - Memory location to receive the X/Column position
// Return Value:
// - True if we successfully pulled the cursor coordinates from the parameters we've stored. False otherwise.
_Success_(return ) bool InputStateMachineEngine::_GetXYPosition(_In_reads_(cParams) const unsigned short* const rgusParams,
const unsigned short cParams,
_Out_ unsigned int* const puiLine,
_Out_ unsigned int* const puiColumn) const
{
bool fSuccess = true;
*puiLine = s_uiDefaultLine;
*puiColumn = s_uiDefaultColumn;
if (cParams == 0)
{
// Empty parameter sequences should use the default
}
else if (cParams == 1)
{
// If there's only one param, leave the default for the column, and retrieve the specified row.
*puiLine = rgusParams[0];
}
else if (cParams == 2)
{
// If there are exactly two parameters, use them.
*puiLine = rgusParams[0];
*puiColumn = rgusParams[1];
}
else
{
fSuccess = false;
}
// Distances of 0 should be changed to 1.
if (*puiLine == 0)
{
*puiLine = s_uiDefaultLine;
}
if (*puiColumn == 0)
{
*puiColumn = s_uiDefaultColumn;
}
return fSuccess;
}