path: root/MdeModulePkg/Universal/Console/TerminalDxe/TerminalConOut.c

/** @file
  Implementation for EFI_SIMPLE_TEXT_OUTPUT_PROTOCOL protocol.

Copyright (c) 2006 - 2010, Intel Corporation. All rights reserved.<BR>
This program and the accompanying materials
are licensed and made available under the terms and conditions of the BSD License
which accompanies this distribution.  The full text of the license may be found at
http://opensource.org/licenses/bsd-license.php

THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.

**/

#include "Terminal.h"

//
// This list is used to define the valid extend chars.
// It also provides a mapping from Unicode to PCANSI or
// ASCII. The ASCII mapping we just made up.
//
//
UNICODE_TO_CHAR  UnicodeToPcAnsiOrAscii[] = {
  { BOXDRAW_HORIZONTAL,                 0xc4, L'-' },
  { BOXDRAW_VERTICAL,                   0xb3, L'|' },
  { BOXDRAW_DOWN_RIGHT,                 0xda, L'/' },
  { BOXDRAW_DOWN_LEFT,                  0xbf, L'\\' },
  { BOXDRAW_UP_RIGHT,                   0xc0, L'\\' },
  { BOXDRAW_UP_LEFT,                    0xd9, L'/' },
  { BOXDRAW_VERTICAL_RIGHT,             0xc3, L'|' },
  { BOXDRAW_VERTICAL_LEFT,              0xb4, L'|' },
  { BOXDRAW_DOWN_HORIZONTAL,            0xc2, L'+' },
  { BOXDRAW_UP_HORIZONTAL,              0xc1, L'+' },
  { BOXDRAW_VERTICAL_HORIZONTAL,        0xc5, L'+' },
  { BOXDRAW_DOUBLE_HORIZONTAL,          0xcd, L'-' },
  { BOXDRAW_DOUBLE_VERTICAL,            0xba, L'|' },
  { BOXDRAW_DOWN_RIGHT_DOUBLE,          0xd5, L'/' },
  { BOXDRAW_DOWN_DOUBLE_RIGHT,          0xd6, L'/' },
  { BOXDRAW_DOUBLE_DOWN_RIGHT,          0xc9, L'/' },
  { BOXDRAW_DOWN_LEFT_DOUBLE,           0xb8, L'\\' },
  { BOXDRAW_DOWN_DOUBLE_LEFT,           0xb7, L'\\' },
  { BOXDRAW_DOUBLE_DOWN_LEFT,           0xbb, L'\\' },
  { BOXDRAW_UP_RIGHT_DOUBLE,            0xd4, L'\\' },
  { BOXDRAW_UP_DOUBLE_RIGHT,            0xd3, L'\\' },
  { BOXDRAW_DOUBLE_UP_RIGHT,            0xc8, L'\\' },
  { BOXDRAW_UP_LEFT_DOUBLE,             0xbe, L'/' },
  { BOXDRAW_UP_DOUBLE_LEFT,             0xbd, L'/' },
  { BOXDRAW_DOUBLE_UP_LEFT,             0xbc, L'/' },
  { BOXDRAW_VERTICAL_RIGHT_DOUBLE,      0xc6, L'|' },
  { BOXDRAW_VERTICAL_DOUBLE_RIGHT,      0xc7, L'|' },
  { BOXDRAW_DOUBLE_VERTICAL_RIGHT,      0xcc, L'|' },
  { BOXDRAW_VERTICAL_LEFT_DOUBLE,       0xb5, L'|' },
  { BOXDRAW_VERTICAL_DOUBLE_LEFT,       0xb6, L'|' },
  { BOXDRAW_DOUBLE_VERTICAL_LEFT,       0xb9, L'|' },
  { BOXDRAW_DOWN_HORIZONTAL_DOUBLE,     0xd1, L'+' },
  { BOXDRAW_DOWN_DOUBLE_HORIZONTAL,     0xd2, L'+' },
  { BOXDRAW_DOUBLE_DOWN_HORIZONTAL,     0xcb, L'+' },
  { BOXDRAW_UP_HORIZONTAL_DOUBLE,       0xcf, L'+' },
  { BOXDRAW_UP_DOUBLE_HORIZONTAL,       0xd0, L'+' },
  { BOXDRAW_DOUBLE_UP_HORIZONTAL,       0xca, L'+' },
  { BOXDRAW_VERTICAL_HORIZONTAL_DOUBLE, 0xd8, L'+' },
  { BOXDRAW_VERTICAL_DOUBLE_HORIZONTAL, 0xd7, L'+' },
  { BOXDRAW_DOUBLE_VERTICAL_HORIZONTAL, 0xce, L'+' },

  { BLOCKELEMENT_FULL_BLOCK,            0xdb, L'*' },
  { BLOCKELEMENT_LIGHT_SHADE,           0xb0, L'+' },

  { GEOMETRICSHAPE_UP_TRIANGLE,         0x1e, L'^' },
  { GEOMETRICSHAPE_RIGHT_TRIANGLE,      0x10, L'>' },
  { GEOMETRICSHAPE_DOWN_TRIANGLE,       0x1f, L'v' },
  { GEOMETRICSHAPE_LEFT_TRIANGLE,       0x11, L'<' },

  { ARROW_LEFT,                         0x3c, L'<' },
  { ARROW_UP,                           0x18, L'^' },
  { ARROW_RIGHT,                        0x3e, L'>' },
  { ARROW_DOWN,                         0x19, L'v' },

  { 0x0000,                             0x00, L'\0' }
};

CHAR16 mSetModeString[]            = { ESC, '[', '=', '3', 'h', 0 };
CHAR16 mSetAttributeString[]       = { ESC, '[', '0', 'm', ESC, '[', '4', '0', 'm', ESC, '[', '4', '0', 'm', 0 };
CHAR16 mClearScreenString[]        = { ESC, '[', '2', 'J', 0 };
CHAR16 mSetCursorPositionString[]  = { ESC, '[', '0', '0', ';', '0', '0', 'H', 0 };

//
// Body of the ConOut functions
//

/**
  Implements EFI_SIMPLE_TEXT_OUTPUT_PROTOCOL.Reset().

  If ExtendeVerification is TRUE, then perform dependent serial device reset,
  and set display mode to mode 0.
  If ExtendedVerification is FALSE, only set display mode to mode 0.

  @param  This                  Indicates the calling context.
  @param  ExtendedVerification  Indicates that the driver may perform a more
                                exhaustive verification operation of the device
                                during reset.

  @retval EFI_SUCCESS           The reset operation succeeds.
  @retval EFI_DEVICE_ERROR      The terminal is not functioning correctly or the serial port reset fails.

**/
EFI_STATUS
EFIAPI
TerminalConOutReset (
  IN  EFI_SIMPLE_TEXT_OUTPUT_PROTOCOL  *This,
  IN  BOOLEAN                          ExtendedVerification
  )
{
  EFI_STATUS    Status;
  TERMINAL_DEV  *TerminalDevice;

  TerminalDevice = TERMINAL_CON_OUT_DEV_FROM_THIS (This);

  //
  // Perform a more exhaustive reset by resetting the serial port.
  //
  if (ExtendedVerification) {
    //
    // Report progress code here
    //
    REPORT_STATUS_CODE_WITH_DEVICE_PATH (
      EFI_PROGRESS_CODE,
      (EFI_PERIPHERAL_REMOTE_CONSOLE | EFI_P_PC_RESET),
      TerminalDevice->DevicePath
      );

    Status = TerminalDevice->SerialIo->Reset (TerminalDevice->SerialIo);
    if (EFI_ERROR (Status)) {
      //
      // Report error code here
      //
      REPORT_STATUS_CODE_WITH_DEVICE_PATH (
        EFI_ERROR_CODE | EFI_ERROR_MINOR,
        (EFI_PERIPHERAL_REMOTE_CONSOLE | EFI_P_EC_CONTROLLER_ERROR),
        TerminalDevice->DevicePath
        );

      return Status;
    }
  }

  This->SetAttribute (This, EFI_TEXT_ATTR (This->Mode->Attribute & 0x0F, EFI_BLACK));

  Status = This->SetMode (This, 0);

  return Status;
}


/**
  Implements EFI_SIMPLE_TEXT_OUTPUT_PROTOCOL.OutputString().

  The Unicode string will be converted to terminal expressible data stream
  and send to terminal via serial port.

  @param  This                    Indicates the calling context.
  @param  WString                 The Null-terminated Unicode string to be displayed
                                  on the terminal screen.

  @retval EFI_SUCCESS             The string is output successfully.
  @retval EFI_DEVICE_ERROR        The serial port fails to send the string out.
  @retval EFI_WARN_UNKNOWN_GLYPH  Indicates that some of the characters in the Unicode string could not
                                  be rendered and are skipped.
  @retval EFI_UNSUPPORTED         If current display mode is out of range.

**/
EFI_STATUS
EFIAPI
TerminalConOutOutputString (
  IN  EFI_SIMPLE_TEXT_OUTPUT_PROTOCOL  *This,
  IN  CHAR16                           *WString
  )
{
  TERMINAL_DEV                *TerminalDevice;
  EFI_SIMPLE_TEXT_OUTPUT_MODE *Mode;
  UINTN                       MaxColumn;
  UINTN                       MaxRow;
  UINTN                       Length;
  UTF8_CHAR                   Utf8Char;
  CHAR8                       GraphicChar;
  CHAR8                       AsciiChar;
  EFI_STATUS                  Status;
  UINT8                       ValidBytes;
  //
  //  flag used to indicate whether condition happens which will cause
  //  return EFI_WARN_UNKNOWN_GLYPH
  //
  BOOLEAN                     Warning;

  ValidBytes  = 0;
  Warning     = FALSE;
  AsciiChar   = 0;

  //
  //  get Terminal device data structure pointer.
  //
  TerminalDevice = TERMINAL_CON_OUT_DEV_FROM_THIS (This);

  //
  //  Get current display mode
  //
  Mode = This->Mode;

  if (Mode->Mode > 2) {
    return EFI_UNSUPPORTED;
  }

  This->QueryMode (
          This,
          Mode->Mode,
          &MaxColumn,
          &MaxRow
          );

  for (; *WString != CHAR_NULL; WString++) {

    switch (TerminalDevice->TerminalType) {

    case PCANSITYPE:
    case VT100TYPE:
    case VT100PLUSTYPE:

      if (!TerminalIsValidTextGraphics (*WString, &GraphicChar, &AsciiChar)) {
        //
        // If it's not a graphic character convert Unicode to ASCII.
        //
        GraphicChar = (CHAR8) *WString;

        if (!(TerminalIsValidAscii (GraphicChar) || TerminalIsValidEfiCntlChar (GraphicChar))) {
          //
          // when this driver use the OutputString to output control string,
          // TerminalDevice->OutputEscChar is set to let the Esc char
          // to be output to the terminal emulation software.
          //
          if ((GraphicChar == 27) && TerminalDevice->OutputEscChar) {
            GraphicChar = 27;
          } else {
            GraphicChar = '?';
            Warning     = TRUE;
          }
        }

        AsciiChar = GraphicChar;

      }

      if (TerminalDevice->TerminalType != PCANSITYPE) {
        GraphicChar = AsciiChar;
      }

      Length = 1;

      Status = TerminalDevice->SerialIo->Write (
                                          TerminalDevice->SerialIo,
                                          &Length,
                                          &GraphicChar
                                          );

      if (EFI_ERROR (Status)) {
        goto OutputError;
      }

      break;

    case VTUTF8TYPE:
      UnicodeToUtf8 (*WString, &Utf8Char, &ValidBytes);
      Length = ValidBytes;
      Status = TerminalDevice->SerialIo->Write (
                                          TerminalDevice->SerialIo,
                                          &Length,
                                          (UINT8 *) &Utf8Char
                                          );
      if (EFI_ERROR (Status)) {
        goto OutputError;
      }
      break;
    }
    //
    //  Update cursor position.
    //
    switch (*WString) {

    case CHAR_BACKSPACE:
      if (Mode->CursorColumn > 0) {
        Mode->CursorColumn--;
      }
      break;

    case CHAR_LINEFEED:
      if (Mode->CursorRow < (INT32) (MaxRow - 1)) {
        Mode->CursorRow++;
      }
      break;

    case CHAR_CARRIAGE_RETURN:
      Mode->CursorColumn = 0;
      break;

    default:
      if (Mode->CursorColumn < (INT32) (MaxColumn - 1)) {

        Mode->CursorColumn++;

      } else {

        Mode->CursorColumn = 0;
        if (Mode->CursorRow < (INT32) (MaxRow - 1)) {
          Mode->CursorRow++;
        }

      }
      break;

    };

  }

  if (Warning) {
    return EFI_WARN_UNKNOWN_GLYPH;
  }

  return EFI_SUCCESS;

OutputError:
  REPORT_STATUS_CODE_WITH_DEVICE_PATH (
    EFI_ERROR_CODE | EFI_ERROR_MINOR,
    (EFI_PERIPHERAL_REMOTE_CONSOLE | EFI_P_EC_OUTPUT_ERROR),
    TerminalDevice->DevicePath
    );

  return EFI_DEVICE_ERROR;
}


/**
  Implements EFI_SIMPLE_TEXT_OUTPUT_PROTOCOL.TestString().

  If one of the characters in the *Wstring is
  neither valid Unicode drawing characters,
  not ASCII code, then this function will return
  EFI_UNSUPPORTED.

  @param  This              Indicates the calling context.
  @param  WString           The Null-terminated Unicode string to be tested.

  @retval EFI_SUCCESS       The terminal is capable of rendering the output string.
  @retval EFI_UNSUPPORTED   Some of the characters in the Unicode string cannot be rendered.

**/
EFI_STATUS
EFIAPI
TerminalConOutTestString (
  IN  EFI_SIMPLE_TEXT_OUTPUT_PROTOCOL  *This,
  IN  CHAR16                           *WString
  )
{
  TERMINAL_DEV  *TerminalDevice;
  EFI_STATUS    Status;

  //
  //  get Terminal device data structure pointer.
  //
  TerminalDevice = TERMINAL_CON_OUT_DEV_FROM_THIS (This);

  switch (TerminalDevice->TerminalType) {

  case PCANSITYPE:
  case VT100TYPE:
  case VT100PLUSTYPE:
    Status = AnsiTestString (TerminalDevice, WString);
    break;

  case VTUTF8TYPE:
    Status = VTUTF8TestString (TerminalDevice, WString);
    break;

  default:
    Status = EFI_UNSUPPORTED;
    break;
  }

  return Status;
}


/**
  Implements EFI_SIMPLE_TEXT_OUTPUT_PROTOCOL.QueryMode().

  It returns information for an available text mode
  that the terminal supports.
  In this driver, we support text mode 80x25 (mode 0),
  80x50 (mode 1), 100x31 (mode 2).

  @param This        Indicates the calling context.
  @param ModeNumber  The mode number to return information on.
  @param Columns     The returned columns of the requested mode.
  @param Rows        The returned rows of the requested mode.

  @retval EFI_SUCCESS       The requested mode information is returned.
  @retval EFI_UNSUPPORTED   The mode number is not valid.
  @retval EFI_DEVICE_ERROR

**/
EFI_STATUS
EFIAPI
TerminalConOutQueryMode (
  IN  EFI_SIMPLE_TEXT_OUTPUT_PROTOCOL  *This,
  IN  UINTN                            ModeNumber,
  OUT UINTN                            *Columns,
  OUT UINTN                            *Rows
  )
{
  if (This->Mode->MaxMode > 3) {
    return EFI_DEVICE_ERROR;
  }

  if (ModeNumber == 0) {
    *Columns  = MODE0_COLUMN_COUNT;
    *Rows     = MODE0_ROW_COUNT;
    return EFI_SUCCESS;
  } else if (ModeNumber == 1) {
    *Columns  = MODE1_COLUMN_COUNT;
    *Rows     = MODE1_ROW_COUNT;
    return EFI_SUCCESS;
  } else if (ModeNumber == 2) {
    *Columns  = MODE2_COLUMN_COUNT;
    *Rows     = MODE2_ROW_COUNT;
    return EFI_SUCCESS;
  }

  return EFI_UNSUPPORTED;
}


/**
  Implements EFI_SIMPLE_TEXT_OUT.SetMode().

  Set the terminal to a specified display mode.
  In this driver, we only support mode 0.

  @param This          Indicates the calling context.
  @param ModeNumber    The text mode to set.

  @retval EFI_SUCCESS       The requested text mode is set.
  @retval EFI_DEVICE_ERROR  The requested text mode cannot be set 
                            because of serial device error.
  @retval EFI_UNSUPPORTED   The text mode number is not valid.

**/
EFI_STATUS
EFIAPI
TerminalConOutSetMode (
  IN  EFI_SIMPLE_TEXT_OUTPUT_PROTOCOL  *This,
  IN  UINTN                            ModeNumber
  )
{
  EFI_STATUS    Status;
  TERMINAL_DEV  *TerminalDevice;

  //
  //  get Terminal device data structure pointer.
  //
  TerminalDevice = TERMINAL_CON_OUT_DEV_FROM_THIS (This);

  if (ModeNumber > 2) {
    return EFI_UNSUPPORTED;
  }

  //
  // Set the current mode
  //
  This->Mode->Mode = (INT32) ModeNumber;

  This->ClearScreen (This);

  TerminalDevice->OutputEscChar = TRUE;
  Status                        = This->OutputString (This, mSetModeString);
  TerminalDevice->OutputEscChar = FALSE;

  if (EFI_ERROR (Status)) {
    return EFI_DEVICE_ERROR;
  }

  This->Mode->Mode  = (INT32) ModeNumber;

  Status            = This->ClearScreen (This);
  if (EFI_ERROR (Status)) {
    return EFI_DEVICE_ERROR;
  }

  return EFI_SUCCESS;

}


/**
  Implements EFI_SIMPLE_TEXT_OUTPUT_PROTOCOL.SetAttribute().

  @param This        Indicates the calling context.
  @param Attribute   The attribute to set. Only bit0..6 are valid, all other bits
                     are undefined and must be zero.

  @retval EFI_SUCCESS        The requested attribute is set.
  @retval EFI_DEVICE_ERROR   The requested attribute cannot be set due to serial port error.
  @retval EFI_UNSUPPORTED    The attribute requested is not defined by EFI spec.

**/
EFI_STATUS
EFIAPI
TerminalConOutSetAttribute (
  IN  EFI_SIMPLE_TEXT_OUTPUT_PROTOCOL  *This,
  IN  UINTN                            Attribute
  )
{
  UINT8         ForegroundControl;
  UINT8         BackgroundControl;
  UINT8         BrightControl;
  INT32         SavedColumn;
  INT32         SavedRow;
  EFI_STATUS    Status;
  TERMINAL_DEV  *TerminalDevice;

  SavedColumn = 0;
  SavedRow    = 0;

  //
  //  get Terminal device data structure pointer.
  //
  TerminalDevice = TERMINAL_CON_OUT_DEV_FROM_THIS (This);

  //
  //  only the bit0..6 of the Attribute is valid
  //
  if ((Attribute | 0x7f) != 0x7f) {
    return EFI_UNSUPPORTED;
  }

  //
  // Skip outputting the command string for the same attribute
  // It improves the terminal performance significantly
  //
  if (This->Mode->Attribute == (INT32) Attribute) {
    return EFI_SUCCESS;
  }

  //
  //  convert Attribute value to terminal emulator
  //  understandable foreground color
  //
  switch (Attribute & 0x07) {

  case EFI_BLACK:
    ForegroundControl = 30;
    break;

  case EFI_BLUE:
    ForegroundControl = 34;
    break;

  case EFI_GREEN:
    ForegroundControl = 32;
    break;

  case EFI_CYAN:
    ForegroundControl = 36;
    break;

  case EFI_RED:
    ForegroundControl = 31;
    break;

  case EFI_MAGENTA:
    ForegroundControl = 35;
    break;

  case EFI_BROWN:
    ForegroundControl = 33;
    break;

  default:

  case EFI_LIGHTGRAY:
    ForegroundControl = 37;
    break;

  }
  //
  //  bit4 of the Attribute indicates bright control
  //  of terminal emulator.
  //
  BrightControl = (UINT8) ((Attribute >> 3) & 1);

  //
  //  convert Attribute value to terminal emulator
  //  understandable background color.
  //
  switch ((Attribute >> 4) & 0x07) {

  case EFI_BLACK:
    BackgroundControl = 40;
    break;

  case EFI_BLUE:
    BackgroundControl = 44;
    break;

  case EFI_GREEN:
    BackgroundControl = 42;
    break;

  case EFI_CYAN:
    BackgroundControl = 46;
    break;

  case EFI_RED:
    BackgroundControl = 41;
    break;

  case EFI_MAGENTA:
    BackgroundControl = 45;
    break;

  case EFI_BROWN:
    BackgroundControl = 43;
    break;

  default:

  case EFI_LIGHTGRAY:
    BackgroundControl = 47;
    break;
  }
  //
  // terminal emulator's control sequence to set attributes
  //
  mSetAttributeString[BRIGHT_CONTROL_OFFSET]          = (CHAR16) ('0' + BrightControl);
  mSetAttributeString[FOREGROUND_CONTROL_OFFSET + 0]  = (CHAR16) ('0' + (ForegroundControl / 10));
  mSetAttributeString[FOREGROUND_CONTROL_OFFSET + 1]  = (CHAR16) ('0' + (ForegroundControl % 10));
  mSetAttributeString[BACKGROUND_CONTROL_OFFSET + 0]  = (CHAR16) ('0' + (BackgroundControl / 10));
  mSetAttributeString[BACKGROUND_CONTROL_OFFSET + 1]  = (CHAR16) ('0' + (BackgroundControl % 10));

  //
  // save current column and row
  // for future scrolling back use.
  //
  SavedColumn                   = This->Mode->CursorColumn;
  SavedRow                      = This->Mode->CursorRow;

  TerminalDevice->OutputEscChar = TRUE;
  Status                        = This->OutputString (This, mSetAttributeString);
  TerminalDevice->OutputEscChar = FALSE;

  if (EFI_ERROR (Status)) {
    return EFI_DEVICE_ERROR;
  }
  //
  //  scroll back to saved cursor position.
  //
  This->Mode->CursorColumn  = SavedColumn;
  This->Mode->CursorRow     = SavedRow;

  This->Mode->Attribute     = (INT32) Attribute;

  return EFI_SUCCESS;

}


/**
  Implements EFI_SIMPLE_TEXT_OUTPUT_PROTOCOL.ClearScreen().
  It clears the ANSI terminal's display to the
  currently selected background color.

  @param This     Indicates the calling context.

  @retval EFI_SUCCESS       The operation completed successfully.
  @retval EFI_DEVICE_ERROR  The terminal screen cannot be cleared due to serial port error.
  @retval EFI_UNSUPPORTED   The terminal is not in a valid display mode.

**/
EFI_STATUS
EFIAPI
TerminalConOutClearScreen (
  IN  EFI_SIMPLE_TEXT_OUTPUT_PROTOCOL  *This
  )
{
  EFI_STATUS    Status;
  TERMINAL_DEV  *TerminalDevice;

  TerminalDevice = TERMINAL_CON_OUT_DEV_FROM_THIS (This);

  //
  //  control sequence for clear screen request
  //
  TerminalDevice->OutputEscChar = TRUE;
  Status                        = This->OutputString (This, mClearScreenString);
  TerminalDevice->OutputEscChar = FALSE;

  if (EFI_ERROR (Status)) {
    return EFI_DEVICE_ERROR;
  }

  Status = This->SetCursorPosition (This, 0, 0);

  return Status;
}


/**
  Implements EFI_SIMPLE_TEXT_OUTPUT_PROTOCOL.SetCursorPosition().

  @param This      Indicates the calling context.
  @param Column    The row to set cursor to.
  @param Row       The column to set cursor to.

  @retval EFI_SUCCESS       The operation completed successfully.
  @retval EFI_DEVICE_ERROR  The request fails due to serial port error.
  @retval EFI_UNSUPPORTED   The terminal is not in a valid text mode, or the cursor position
                            is invalid for current mode.

**/
EFI_STATUS
EFIAPI
TerminalConOutSetCursorPosition (
  IN  EFI_SIMPLE_TEXT_OUTPUT_PROTOCOL  *This,
  IN  UINTN                            Column,
  IN  UINTN                            Row
  )
{
  EFI_SIMPLE_TEXT_OUTPUT_MODE *Mode;
  UINTN                       MaxColumn;
  UINTN                       MaxRow;
  EFI_STATUS                  Status;
  TERMINAL_DEV                *TerminalDevice;

  TerminalDevice = TERMINAL_CON_OUT_DEV_FROM_THIS (This);

  //
  //  get current mode
  //
  Mode = This->Mode;

  //
  //  get geometry of current mode
  //
  Status = This->QueryMode (
                  This,
                  Mode->Mode,
                  &MaxColumn,
                  &MaxRow
                  );
  if (EFI_ERROR (Status)) {
    return EFI_UNSUPPORTED;
  }

  if (Column >= MaxColumn || Row >= MaxRow) {
    return EFI_UNSUPPORTED;
  }
  //
  // control sequence to move the cursor
  //
  mSetCursorPositionString[ROW_OFFSET + 0]    = (CHAR16) ('0' + ((Row + 1) / 10));
  mSetCursorPositionString[ROW_OFFSET + 1]    = (CHAR16) ('0' + ((Row + 1) % 10));
  mSetCursorPositionString[COLUMN_OFFSET + 0] = (CHAR16) ('0' + ((Column + 1) / 10));
  mSetCursorPositionString[COLUMN_OFFSET + 1] = (CHAR16) ('0' + ((Column + 1) % 10));

  TerminalDevice->OutputEscChar               = TRUE;
  Status = This->OutputString (This, mSetCursorPositionString);
  TerminalDevice->OutputEscChar = FALSE;

  if (EFI_ERROR (Status)) {
    return EFI_DEVICE_ERROR;
  }
  //
  //  update current cursor position
  //  in the Mode data structure.
  //
  Mode->CursorColumn  = (INT32) Column;
  Mode->CursorRow     = (INT32) Row;

  return EFI_SUCCESS;
}


/**
  Implements SIMPLE_TEXT_OUTPUT.EnableCursor().

  In this driver, the cursor cannot be hidden.

  @param This      Indicates the calling context.
  @param Visible   If TRUE, the cursor is set to be visible,
                   If FALSE, the cursor is set to be invisible.

  @retval EFI_SUCCESS      The request is valid.
  @retval EFI_UNSUPPORTED  The terminal does not support cursor hidden.

**/
EFI_STATUS
EFIAPI
TerminalConOutEnableCursor (
  IN  EFI_SIMPLE_TEXT_OUTPUT_PROTOCOL  *This,
  IN  BOOLEAN                          Visible
  )
{
  if (!Visible) {
    return EFI_UNSUPPORTED;
  }

  return EFI_SUCCESS;
}


/**
  Detects if a Unicode char is for Box Drawing text graphics.

  @param  Graphic      Unicode char to test.
  @param  PcAnsi       Optional pointer to return PCANSI equivalent of
                       Graphic.
  @param  Ascii        Optional pointer to return ASCII equivalent of
                       Graphic.

  @retval TRUE         If Graphic is a supported Unicode Box Drawing character.

**/
BOOLEAN
TerminalIsValidTextGraphics (
  IN  CHAR16  Graphic,
  OUT CHAR8   *PcAnsi, OPTIONAL
  OUT CHAR8   *Ascii OPTIONAL
  )
{
  UNICODE_TO_CHAR *Table;

  if ((((Graphic & 0xff00) != 0x2500) && ((Graphic & 0xff00) != 0x2100))) {
    //
    // Unicode drawing code charts are all in the 0x25xx range,
    //  arrows are 0x21xx
    //
    return FALSE;
  }

  for (Table = UnicodeToPcAnsiOrAscii; Table->Unicode != 0x0000; Table++) {
    if (Graphic == Table->Unicode) {
      if (PcAnsi != NULL) {
        *PcAnsi = Table->PcAnsi;
      }

      if (Ascii != NULL) {
        *Ascii = Table->Ascii;
      }

      return TRUE;
    }
  }

  return FALSE;
}

/**
  Detects if a valid ASCII char.

  @param  Ascii        An ASCII character.
                       
  @retval TRUE         If it is a valid ASCII character.
  @retval FALSE        If it is not a valid ASCII character.

**/
BOOLEAN
TerminalIsValidAscii (
  IN  CHAR16  Ascii
  )
{
  //
  // valid ascii code lies in the extent of 0x20 ~ 0x7f
  //
  if ((Ascii >= 0x20) && (Ascii <= 0x7f)) {
    return TRUE;
  }

  return FALSE;
}

/**
  Detects if a valid EFI control character.

  @param  CharC        An input EFI Control character.
                       
  @retval TRUE         If it is a valid EFI control character.
  @retval FALSE        If it is not a valid EFI control character.

**/
BOOLEAN
TerminalIsValidEfiCntlChar (
  IN  CHAR16  CharC
  )
{
  //
  // only support four control characters.
  //
  if (CharC == CHAR_NULL ||
      CharC == CHAR_BACKSPACE ||
      CharC == CHAR_LINEFEED ||
      CharC == CHAR_CARRIAGE_RETURN ||
      CharC == CHAR_TAB
      ) {
    return TRUE;
  }

  return FALSE;
}