keytrans.c

/**
 * PROJECT:         Native Shell
 * COPYRIGHT:       LGPL; See LICENSE in the top level directory
 * FILE:            keytrans.c
 * DESCRIPTION:     Keyboard codes translation.
 * DEVELOPERS:      See CONTRIBUTORS.md in the top level directory
 */

#include "precomp.h"

typedef struct _SCANTOASCII
{
    USHORT ScanCode;
    UCHAR Normal;
    UCHAR Shift;
} SCANTOASCII, *PSCANTOASCII;

SCANTOASCII ScanToAscii[] = {
    {0x1e, 'a', 'A'},
    {0x30, 'b', 'B'},
    {0x2e, 'c', 'C'},
    {0x20, 'd', 'D'},
    {0x12, 'e', 'E'},
    {0x21, 'f', 'F'},
    {0x22, 'g', 'G'},
    {0x23, 'h', 'H'},
    {0x17, 'i', 'I'},
    {0x24, 'j', 'J'},
    {0x25, 'k', 'K'},
    {0x26, 'l', 'L'},
    {0x32, 'm', 'M'},
    {0x31, 'n', 'N'},
    {0x18, 'o', 'O'},
    {0x19, 'p', 'P'},
    {0x10, 'q', 'Q'},
    {0x13, 'r', 'R'},
    {0x1f, 's', 'S'},
    {0x14, 't', 'T'},
    {0x16, 'u', 'U'},
    {0x2f, 'v', 'V'},
    {0x11, 'w', 'W'},
    {0x2d, 'x', 'X'},
    {0x15, 'y', 'Y'},
    {0x2c, 'z', 'Z'},

    {0x02, '1', '!'},
    {0x03, '2', '@'},
    {0x04, '3', '#'},
    {0x05, '4', '$'},
    {0x06, '5', '%'},
    {0x07, '6', '^'},
    {0x08, '7', '&'},
    {0x09, '8', '*'},
    {0x0a, '9', '('},
    {0x0b, '0', ')'},

    {0x29, '\'', '~'},
    {0x0c, '-', '_'},
    {0x0d, '=', '+'},
    {0x1a, '[', '{'},
    {0x1b, ']', '}'},
    {0x2b, '\\', '|'},
    {0x27, ';', ':'},
    {0x28, '\'', '"'},
    {0x33, ',', '<'},
    {0x34, '.', '>'},
    {0x35, '/', '?'},

    {0x4a, '-', '-'},
    {0x4e, '+', '+'},
    {0x37, '*', '*'},

    {0x39, ' ', ' '},

    {0x1c, '\r', '\r'},
    {0x0e, 0x08, 0x08}, /* backspace */

    {0, 0, 0}};

static void IntUpdateControlKeyState(LPDWORD State, PKEYBOARD_INPUT_DATA InputData)
{
    DWORD Value = 0;

    if (InputData->Flags & KEY_E1) /* Only the pause key has E1 */
        return;

    if (!(InputData->Flags & KEY_E0))
    {
        switch (InputData->MakeCode)
        {
        case 0x2a:
        case 0x36:
            Value = SHIFT_PRESSED;
            break;
        case 0x1d:
            Value = LEFT_CTRL_PRESSED;
            break;
        case 0x38:
            Value = LEFT_ALT_PRESSED;
            break;
        case 0x45:
            Value = NUMLOCK_ON;
            if (!(InputData->Flags & KEY_BREAK))
                *State ^= Value;
            return;
        default:
            return;
        }
    }
    else
    {
        switch (InputData->MakeCode)
        {
        case 0x1d:
            Value = RIGHT_CTRL_PRESSED;
            break;
        case 0x38:
            Value = RIGHT_ALT_PRESSED;
            break;
        default:
            return;
        }
    }

    if (InputData->Flags & KEY_BREAK)
        *State &= ~Value;
    else
        *State |= Value;
}

static UCHAR IntAsciiFromInput(PKEYBOARD_INPUT_DATA InputData, DWORD KeyState)
{
    UINT Counter = 0;

    while (ScanToAscii[Counter].ScanCode != 0)
    {
        if (ScanToAscii[Counter].ScanCode == InputData->MakeCode)
        {
            if (KeyState & SHIFT_PRESSED)
                return ScanToAscii[Counter].Shift;
            return ScanToAscii[Counter].Normal;
        }
        Counter++;
    }
    return 0;
}

/*
 * Only the bKeyDown and AsciiChar members are used in the zenwinx library.
 */
void IntTranslateKey(PKEYBOARD_INPUT_DATA InputData, KBD_RECORD *kbd_rec)
{
    static DWORD dwControlKeyState;

    kbd_rec->wVirtualScanCode = InputData->MakeCode;
    kbd_rec->bKeyDown = (InputData->Flags & KEY_BREAK) ? FALSE : TRUE;

    IntUpdateControlKeyState(&dwControlKeyState, InputData);
    kbd_rec->dwControlKeyState = dwControlKeyState;

    if (InputData->Flags & KEY_E0)
        kbd_rec->dwControlKeyState |= ENHANCED_KEY;

    kbd_rec->AsciiChar = IntAsciiFromInput(InputData, kbd_rec->dwControlKeyState);
}