trunk/rdesktop/xkeymap.c

/*
   rdesktop: A Remote Desktop Protocol client.
   User interface services - X keyboard mapping

   Copyright (C) Matthew Chapman 1999-2005
   Copyright (C) Peter Astrand <peter@cendio.se> 2003
   
   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 2 of the License, or
   (at your option) any later version.
   
   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/

#ifdef RDP2VNC
#include "vnc/x11stubs.h"
#else
#include <X11/Xlib.h>
#include <X11/keysym.h>
#endif

#include <ctype.h>
#include <limits.h>
#include <time.h>
#include <string.h>
#include "rdesktop.h"
#include "scancodes.h"

#define KEYMAP_SIZE 0xffff+1
#define KEYMAP_MASK 0xffff
#define KEYMAP_MAX_LINE_LENGTH 80

extern Display *g_display;
extern Window g_wnd;
extern char keymapname[16];
extern int g_keylayout;
extern int g_win_button_size;
extern BOOL g_enable_compose;
extern BOOL g_use_rdp5;
extern BOOL g_numlock_sync;

static BOOL keymap_loaded;
static key_translation *keymap[KEYMAP_SIZE];
static int min_keycode;
static uint16 remote_modifier_state = 0;
static uint16 saved_remote_modifier_state = 0;

static void update_modifier_state(uint8 scancode, BOOL pressed);

/* Free key_translation structure, including linked list */
static void
free_key_translation(key_translation * ptr)
{
        key_translation *next;

        while (ptr)
        {
                next = ptr->next;
                xfree(ptr);
                ptr = next;
        }
}

static void
add_to_keymap(char *keyname, uint8 scancode, uint16 modifiers, char *mapname)
{
        KeySym keysym;
        key_translation *tr;

        keysym = XStringToKeysym(keyname);
        if (keysym == NoSymbol)
        {
                DEBUG_KBD(("Bad keysym \"%s\" in keymap %s (ignoring)\n", keyname, mapname));
                return;
        }

        DEBUG_KBD(("Adding translation, keysym=0x%x, scancode=0x%x, "
                   "modifiers=0x%x\n", (unsigned int) keysym, scancode, modifiers));

        tr = (key_translation *) xmalloc(sizeof(key_translation));
        memset(tr, 0, sizeof(key_translation));
        tr->scancode = scancode;
        tr->modifiers = modifiers;
        free_key_translation(keymap[keysym & KEYMAP_MASK]);
        keymap[keysym & KEYMAP_MASK] = tr;

        return;
}

static void
add_sequence(char *rest, char *mapname)
{
        KeySym keysym;
        key_translation *tr, **prev_next;
        size_t chars;
        char keyname[KEYMAP_MAX_LINE_LENGTH];

        /* Skip over whitespace after the sequence keyword */
        chars = strspn(rest, " \t");
        rest += chars;

        /* Fetch the keysym name */
        chars = strcspn(rest, " \t\0");
        STRNCPY(keyname, rest, chars + 1);
        rest += chars;

        keysym = XStringToKeysym(keyname);
        if (keysym == NoSymbol)
        {
                DEBUG_KBD(("Bad keysym \"%s\" in keymap %s (ignoring line)\n", keyname, mapname));
                return;
        }


        DEBUG_KBD(("Adding sequence for keysym (0x%lx, %s) -> ", keysym, keyname));

        free_key_translation(keymap[keysym & KEYMAP_MASK]);
        prev_next = &keymap[keysym & KEYMAP_MASK];

        while (*rest)
        {
                /* Skip whitespace */
                chars = strspn(rest, " \t");
                rest += chars;

                /* Fetch the keysym name */
                chars = strcspn(rest, " \t\0");
                STRNCPY(keyname, rest, chars + 1);
                rest += chars;

                keysym = XStringToKeysym(keyname);
                if (keysym == NoSymbol)
                {
                        DEBUG_KBD(("Bad keysym \"%s\" in keymap %s (ignoring line)\n", keyname,
                                   mapname));
                        return;
                }

                /* Allocate space for key_translation structure */
                tr = (key_translation *) xmalloc(sizeof(key_translation));
                memset(tr, 0, sizeof(key_translation));
                *prev_next = tr;
                prev_next = &tr->next;
                tr->seq_keysym = keysym;

                DEBUG_KBD(("0x%x, ", (unsigned int) keysym));
        }
        DEBUG_KBD(("\n"));
}

/* Joins two path components. The result should be freed with
   xfree(). */
static char *
pathjoin(const char *a, const char *b)
{
        char *result;
        result = xmalloc(PATH_MAX * 2 + 1);

        if (b[0] == '/')
        {
                strncpy(result, b, PATH_MAX);
        }
        else
        {
                strncpy(result, a, PATH_MAX);
                strcat(result, "/");
                strncat(result, b, PATH_MAX);
        }
        return result;
}

/* Try to open a keymap with fopen() */
FILE *
xkeymap_open(const char *filename)
{
        char *path1, *path2;
        char *home;
        FILE *fp;

        /* Try ~/.rdesktop/keymaps */
        home = getenv("HOME");
        if (home)
        {
                path1 = pathjoin(home, ".rdesktop/keymaps");
                path2 = pathjoin(path1, filename);
                xfree(path1);
                fp = fopen(path2, "r");
                xfree(path2);
                if (fp)
                        return fp;
        }

        /* Try KEYMAP_PATH */
        path1 = pathjoin(KEYMAP_PATH, filename);
        fp = fopen(path1, "r");
        xfree(path1);
        if (fp)
                return fp;

        /* Try current directory, in case we are running from the source
           tree */
        path1 = pathjoin("keymaps", filename);
        fp = fopen(path1, "r");
        xfree(path1);
        if (fp)
                return fp;

        return NULL;
}

static BOOL
xkeymap_read(char *mapname)
{
        FILE *fp;
        char line[KEYMAP_MAX_LINE_LENGTH];
        unsigned int line_num = 0;
        unsigned int line_length = 0;
        char *keyname, *p;
        char *line_rest;
        uint8 scancode;
        uint16 modifiers;

        fp = xkeymap_open(mapname);
        if (fp == NULL)
        {
                error("Failed to open keymap %s\n", mapname);
                return False;
        }

        /* FIXME: More tolerant on white space */
        while (fgets(line, sizeof(line), fp) != NULL)
        {
                line_num++;

                /* Replace the \n with \0 */
                p = strchr(line, '\n');
                if (p != NULL)
                        *p = 0;

                line_length = strlen(line);

                /* Completely empty line */
                if (strspn(line, " \t\n\r\f\v") == line_length)
                {
                        continue;
                }

                /* Include */
                if (strncmp(line, "include ", 8) == 0)
                {
                        if (!xkeymap_read(line + 8))
                                return False;
                        continue;
                }

                /* map */
                if (strncmp(line, "map ", 4) == 0)
                {
                        g_keylayout = strtol(line + 4, NULL, 16);
                        DEBUG_KBD(("Keylayout 0x%x\n", g_keylayout));
                        continue;
                }

                /* compose */
                if (strncmp(line, "enable_compose", 15) == 0)
                {
                        DEBUG_KBD(("Enabling compose handling\n"));
                        g_enable_compose = True;
                        continue;
                }

                /* sequence */
                if (strncmp(line, "sequence", 8) == 0)
                {
                        add_sequence(line + 8, mapname);
                        continue;
                }

                /* Comment */
                if (line[0] == '#')
                {
                        continue;
                }

                /* Normal line */
                keyname = line;
                p = strchr(line, ' ');
                if (p == NULL)
                {
                        error("Bad line %d in keymap %s\n", line_num, mapname);
                        continue;
                }
                else
                {
                        *p = 0;
                }

                /* scancode */
                p++;
                scancode = strtol(p, &line_rest, 16);

                /* flags */
                /* FIXME: Should allow case-insensitive flag names. 
                   Fix by using lex+yacc... */
                modifiers = 0;
                if (strstr(line_rest, "altgr"))
                {
                        MASK_ADD_BITS(modifiers, MapAltGrMask);
                }

                if (strstr(line_rest, "shift"))
                {
                        MASK_ADD_BITS(modifiers, MapLeftShiftMask);
                }

                if (strstr(line_rest, "numlock"))
                {
                        MASK_ADD_BITS(modifiers, MapNumLockMask);
                }

                if (strstr(line_rest, "localstate"))
                {
                        MASK_ADD_BITS(modifiers, MapLocalStateMask);
                }

                if (strstr(line_rest, "inhibit"))
                {
                        MASK_ADD_BITS(modifiers, MapInhibitMask);
                }

                add_to_keymap(keyname, scancode, modifiers, mapname);

                if (strstr(line_rest, "addupper"))
                {
                        /* Automatically add uppercase key, with same modifiers 
                           plus shift */
                        for (p = keyname; *p; p++)
                                *p = toupper((int) *p);
                        MASK_ADD_BITS(modifiers, MapLeftShiftMask);
                        add_to_keymap(keyname, scancode, modifiers, mapname);
                }
        }

        fclose(fp);
        return True;
}


/* Before connecting and creating UI */
void
xkeymap_init(void)
{
        unsigned int max_keycode;
        char *mapname_ptr;

        if (strcmp(keymapname, "none"))
        {
                if (xkeymap_read(keymapname))
                        keymap_loaded = True;
        }

        XDisplayKeycodes(g_display, &min_keycode, (int *) &max_keycode);
}

static void
send_winkey(uint32 ev_time, BOOL pressed, BOOL leftkey)
{
        uint8 winkey;

        if (leftkey)
                winkey = SCANCODE_CHAR_LWIN;
        else
                winkey = SCANCODE_CHAR_RWIN;

        if (pressed)
        {
                if (g_use_rdp5)
                {
                        rdp_send_scancode(ev_time, RDP_KEYPRESS, winkey);
                }
                else
                {
                        /* RDP4 doesn't support winkey. Fake with Ctrl-Esc */
                        rdp_send_scancode(ev_time, RDP_KEYPRESS, SCANCODE_CHAR_LCTRL);
                        rdp_send_scancode(ev_time, RDP_KEYPRESS, SCANCODE_CHAR_ESC);
                }
        }
        else
        {
                /* key released */
                if (g_use_rdp5)
                {
                        rdp_send_scancode(ev_time, RDP_KEYRELEASE, winkey);
                }
                else
                {
                        rdp_send_scancode(ev_time, RDP_KEYRELEASE, SCANCODE_CHAR_ESC);
                        rdp_send_scancode(ev_time, RDP_KEYRELEASE, SCANCODE_CHAR_LCTRL);
                }
        }
}

static void
reset_winkey(uint32 ev_time)
{
        if (g_use_rdp5)
        {
                /* For some reason, it seems to suffice to release
                 *either* the left or right winkey. */
                rdp_send_scancode(ev_time, RDP_KEYRELEASE, SCANCODE_CHAR_LWIN);
        }
}

/* Handle special key combinations */
BOOL
handle_special_keys(uint32 keysym, unsigned int state, uint32 ev_time, BOOL pressed)
{
        switch (keysym)
        {
                case XK_Return:
                        if ((get_key_state(state, XK_Alt_L) || get_key_state(state, XK_Alt_R))
                            && (get_key_state(state, XK_Control_L)
                                || get_key_state(state, XK_Control_R)))
                        {
                                /* Ctrl-Alt-Enter: toggle full screen */
                                if (pressed)
                                        xwin_toggle_fullscreen();
                                return True;
                        }
                        break;

                case XK_Break:
                        /* Send Break sequence E0 46 E0 C6 */
                        if (pressed)
                        {
                                rdp_send_scancode(ev_time, RDP_KEYPRESS,
                                                  (SCANCODE_EXTENDED | 0x46));
                                rdp_send_scancode(ev_time, RDP_KEYPRESS,
                                                  (SCANCODE_EXTENDED | 0xc6));
                        }
                        /* No release sequence */
                        return True;
                        break;

                case XK_Pause:
                        /* According to MS Keyboard Scan Code
                           Specification, pressing Pause should result
                           in E1 1D 45 E1 9D C5. I'm not exactly sure
                           of how this is supposed to be sent via
                           RDP. The code below seems to work, but with
                           the side effect that Left Ctrl stays
                           down. Therefore, we release it when Pause
                           is released. */
                        if (pressed)
                        {
                                rdp_send_input(ev_time, RDP_INPUT_SCANCODE, RDP_KEYPRESS, 0xe1, 0);
                                rdp_send_input(ev_time, RDP_INPUT_SCANCODE, RDP_KEYPRESS, 0x1d, 0);
                                rdp_send_input(ev_time, RDP_INPUT_SCANCODE, RDP_KEYPRESS, 0x45, 0);
                                rdp_send_input(ev_time, RDP_INPUT_SCANCODE, RDP_KEYPRESS, 0xe1, 0);
                                rdp_send_input(ev_time, RDP_INPUT_SCANCODE, RDP_KEYPRESS, 0x9d, 0);
                                rdp_send_input(ev_time, RDP_INPUT_SCANCODE, RDP_KEYPRESS, 0xc5, 0);
                        }
                        else
                        {
                                /* Release Left Ctrl */
                                rdp_send_input(ev_time, RDP_INPUT_SCANCODE, RDP_KEYRELEASE,
                                               0x1d, 0);
                        }
                        return True;
                        break;

                case XK_Meta_L: /* Windows keys */
                case XK_Super_L:
                case XK_Hyper_L:
                        send_winkey(ev_time, pressed, True);
                        return True;
                        break;

                case XK_Meta_R:
                case XK_Super_R:
                case XK_Hyper_R:
                        send_winkey(ev_time, pressed, False);
                        return True;
                        break;

                case XK_space:
                        /* Prevent access to the Windows system menu in single app mode */
                        if (g_win_button_size
                            && (get_key_state(state, XK_Alt_L) || get_key_state(state, XK_Alt_R)))
                                return True;
                        break;

                case XK_Num_Lock:
                        /* Synchronize on key release */
                        if (g_numlock_sync && !pressed)
                                rdp_send_input(0, RDP_INPUT_SYNCHRONIZE, 0,
                                               ui_get_numlock_state(read_keyboard_state()), 0);

                        /* Inhibit */
                        return True;
                        break;

        }
        return False;
}


key_translation
xkeymap_translate_key(uint32 keysym, unsigned int keycode, unsigned int state)
{
        key_translation tr = { 0, 0, 0, 0 };
        key_translation *ptr;

        ptr = keymap[keysym & KEYMAP_MASK];
        if (ptr)
        {
                tr = *ptr;
                if (tr.seq_keysym == 0) /* Normal scancode translation */
                {
                        if (tr.modifiers & MapInhibitMask)
                        {
                                DEBUG_KBD(("Inhibiting key\n"));
                                tr.scancode = 0;
                                return tr;
                        }

                        if (tr.modifiers & MapLocalStateMask)
                        {
                                /* The modifiers to send for this key should be obtained
                                   from the local state. Currently, only shift is implemented. */
                                if (state & ShiftMask)
                                {
                                        tr.modifiers = MapLeftShiftMask;
                                }
                        }

                        if ((tr.modifiers & MapLeftShiftMask)
                            && ((remote_modifier_state & MapLeftCtrlMask)
                                || (remote_modifier_state & MapRightCtrlMask))
                            && get_key_state(state, XK_Caps_Lock))
                        {
                                DEBUG_KBD(("CapsLock + Ctrl pressed, releasing LeftShift\n"));
                                tr.modifiers ^= MapLeftShiftMask;
                        }

                        DEBUG_KBD(("Found scancode translation, scancode=0x%x, modifiers=0x%x\n",
                                   tr.scancode, tr.modifiers));
                }
        }
        else
        {
                if (keymap_loaded)
                        warning("No translation for (keysym 0x%lx, %s)\n", keysym,
                                get_ksname(keysym));

                /* not in keymap, try to interpret the raw scancode */
                if (((int) keycode >= min_keycode) && (keycode <= 0x60))
                {
                        tr.scancode = keycode - min_keycode;

                        /* The modifiers to send for this key should be
                           obtained from the local state. Currently, only
                           shift is implemented. */
                        if (state & ShiftMask)
                        {
                                tr.modifiers = MapLeftShiftMask;
                        }

                        DEBUG_KBD(("Sending guessed scancode 0x%x\n", tr.scancode));
                }
                else
                {
                        DEBUG_KBD(("No good guess for keycode 0x%x found\n", keycode));
                }
        }

        return tr;
}

void
xkeymap_send_keys(uint32 keysym, unsigned int keycode, unsigned int state, uint32 ev_time,
                  BOOL pressed)
{
        key_translation tr, *ptr;
        tr = xkeymap_translate_key(keysym, keycode, state);

        if (tr.seq_keysym == 0)
        {
                /* Scancode translation */
                if (tr.scancode == 0)
                        return;

                if (pressed)
                {
                        save_remote_modifiers(tr.scancode);
                        ensure_remote_modifiers(ev_time, tr);
                        rdp_send_scancode(ev_time, RDP_KEYPRESS, tr.scancode);
                        restore_remote_modifiers(ev_time, tr.scancode);
                }
                else
                {
                        rdp_send_scancode(ev_time, RDP_KEYRELEASE, tr.scancode);
                }
                return;
        }

        /* Sequence, only on key down */
        if (pressed)
        {
                ptr = &tr;
                do
                {
                        DEBUG_KBD(("Handling sequence element, keysym=0x%x\n",
                                   (unsigned int) ptr->seq_keysym));
                        xkeymap_send_keys(ptr->seq_keysym, keycode, state, ev_time, True);
                        xkeymap_send_keys(ptr->seq_keysym, keycode, state, ev_time, False);
                        ptr = ptr->next;
                }
                while (ptr);
        }
}

uint16
xkeymap_translate_button(unsigned int button)
{
        switch (button)
        {
                case Button1:   /* left */
                        return MOUSE_FLAG_BUTTON1;
                case Button2:   /* middle */
                        return MOUSE_FLAG_BUTTON3;
                case Button3:   /* right */
                        return MOUSE_FLAG_BUTTON2;
                case Button4:   /* wheel up */
                        return MOUSE_FLAG_BUTTON4;
                case Button5:   /* wheel down */
                        return MOUSE_FLAG_BUTTON5;
        }

        return 0;
}

char *
get_ksname(uint32 keysym)
{
        char *ksname = NULL;

        if (keysym == NoSymbol)
                ksname = "NoSymbol";
        else if (!(ksname = XKeysymToString(keysym)))
                ksname = "(no name)";

        return ksname;
}

static BOOL
is_modifier(uint8 scancode)
{
        switch (scancode)
        {
                case SCANCODE_CHAR_LSHIFT:
                case SCANCODE_CHAR_RSHIFT:
                case SCANCODE_CHAR_LCTRL:
                case SCANCODE_CHAR_RCTRL:
                case SCANCODE_CHAR_LALT:
                case SCANCODE_CHAR_RALT:
                case SCANCODE_CHAR_LWIN:
                case SCANCODE_CHAR_RWIN:
                case SCANCODE_CHAR_NUMLOCK:
                        return True;
                default:
                        break;
        }
        return False;
}

void
save_remote_modifiers(uint8 scancode)
{
        if (is_modifier(scancode))
                return;

        saved_remote_modifier_state = remote_modifier_state;
}

void
restore_remote_modifiers(uint32 ev_time, uint8 scancode)
{
        key_translation dummy;

        if (is_modifier(scancode))
                return;

        dummy.scancode = 0;
        dummy.modifiers = saved_remote_modifier_state;
        ensure_remote_modifiers(ev_time, dummy);
}

void
ensure_remote_modifiers(uint32 ev_time, key_translation tr)
{
        /* If this key is a modifier, do nothing */
        if (is_modifier(tr.scancode))
                return;

        if (!g_numlock_sync)
        {
                /* NumLock */
                if (MASK_HAS_BITS(tr.modifiers, MapNumLockMask)
                    != MASK_HAS_BITS(remote_modifier_state, MapNumLockMask))
                {
                        /* The remote modifier state is not correct */
                        uint16 new_remote_state;

                        if (MASK_HAS_BITS(tr.modifiers, MapNumLockMask))
                        {
                                DEBUG_KBD(("Remote NumLock state is incorrect, activating NumLock.\n"));
                                new_remote_state = KBD_FLAG_NUMLOCK;
                                remote_modifier_state = MapNumLockMask;
                        }
                        else
                        {
                                DEBUG_KBD(("Remote NumLock state is incorrect, deactivating NumLock.\n"));
                                new_remote_state = 0;
                                remote_modifier_state = 0;
                        }

                        rdp_send_input(0, RDP_INPUT_SYNCHRONIZE, 0, new_remote_state, 0);
                }
        }


        /* Shift. Left shift and right shift are treated as equal; either is fine. */
        if (MASK_HAS_BITS(tr.modifiers, MapShiftMask)
            != MASK_HAS_BITS(remote_modifier_state, MapShiftMask))
        {
                /* The remote modifier state is not correct */
                if (MASK_HAS_BITS(tr.modifiers, MapLeftShiftMask))
                {
                        /* Needs left shift. Send down. */
                        rdp_send_scancode(ev_time, RDP_KEYPRESS, SCANCODE_CHAR_LSHIFT);
                }
                else if (MASK_HAS_BITS(tr.modifiers, MapRightShiftMask))
                {
                        /* Needs right shift. Send down. */
                        rdp_send_scancode(ev_time, RDP_KEYPRESS, SCANCODE_CHAR_RSHIFT);
                }
                else
                {
                        /* Should not use this modifier. Send up for shift currently pressed. */
                        if (MASK_HAS_BITS(remote_modifier_state, MapLeftShiftMask))
                                /* Left shift is down */
                                rdp_send_scancode(ev_time, RDP_KEYRELEASE, SCANCODE_CHAR_LSHIFT);
                        else
                                /* Right shift is down */
                                rdp_send_scancode(ev_time, RDP_KEYRELEASE, SCANCODE_CHAR_RSHIFT);
                }
        }

        /* AltGr */
        if (MASK_HAS_BITS(tr.modifiers, MapAltGrMask)
            != MASK_HAS_BITS(remote_modifier_state, MapAltGrMask))
        {
                /* The remote modifier state is not correct */
                if (MASK_HAS_BITS(tr.modifiers, MapAltGrMask))
                {
                        /* Needs this modifier. Send down. */
                        rdp_send_scancode(ev_time, RDP_KEYPRESS, SCANCODE_CHAR_RALT);
                }
                else
                {
                        /* Should not use this modifier. Send up. */
                        rdp_send_scancode(ev_time, RDP_KEYRELEASE, SCANCODE_CHAR_RALT);
                }
        }


}


unsigned int
read_keyboard_state()
{
#ifdef RDP2VNC
        return 0;
#else
        unsigned int state;
        Window wdummy;
        int dummy;

        XQueryPointer(g_display, g_wnd, &wdummy, &wdummy, &dummy, &dummy, &dummy, &dummy, &state);
        return state;
#endif
}


uint16
ui_get_numlock_state(unsigned int state)
{
        uint16 numlock_state = 0;

        if (get_key_state(state, XK_Num_Lock))
                numlock_state = KBD_FLAG_NUMLOCK;

        return numlock_state;
}


void
reset_modifier_keys()
{
        unsigned int state = read_keyboard_state();

        /* reset keys */
        uint32 ev_time;
        ev_time = time(NULL);

        if (MASK_HAS_BITS(remote_modifier_state, MapLeftShiftMask)
            && !get_key_state(state, XK_Shift_L))
                rdp_send_scancode(ev_time, RDP_KEYRELEASE, SCANCODE_CHAR_LSHIFT);

        if (MASK_HAS_BITS(remote_modifier_state, MapRightShiftMask)
            && !get_key_state(state, XK_Shift_R))
                rdp_send_scancode(ev_time, RDP_KEYRELEASE, SCANCODE_CHAR_RSHIFT);

        if (MASK_HAS_BITS(remote_modifier_state, MapLeftCtrlMask)
            && !get_key_state(state, XK_Control_L))
                rdp_send_scancode(ev_time, RDP_KEYRELEASE, SCANCODE_CHAR_LCTRL);

        if (MASK_HAS_BITS(remote_modifier_state, MapRightCtrlMask)
            && !get_key_state(state, XK_Control_R))
                rdp_send_scancode(ev_time, RDP_KEYRELEASE, SCANCODE_CHAR_RCTRL);

        if (MASK_HAS_BITS(remote_modifier_state, MapLeftAltMask) && !get_key_state(state, XK_Alt_L))
                rdp_send_scancode(ev_time, RDP_KEYRELEASE, SCANCODE_CHAR_LALT);

        if (MASK_HAS_BITS(remote_modifier_state, MapRightAltMask) &&
            !get_key_state(state, XK_Alt_R) && !get_key_state(state, XK_Mode_switch)
            && !get_key_state(state, XK_ISO_Level3_Shift))
                rdp_send_scancode(ev_time, RDP_KEYRELEASE, SCANCODE_CHAR_RALT);

        reset_winkey(ev_time);

        if (g_numlock_sync)
                rdp_send_input(ev_time, RDP_INPUT_SYNCHRONIZE, 0, ui_get_numlock_state(state), 0);
}


static void
update_modifier_state(uint8 scancode, BOOL pressed)
{
#ifdef WITH_DEBUG_KBD
        uint16 old_modifier_state;

        old_modifier_state = remote_modifier_state;
#endif

        switch (scancode)
        {
                case SCANCODE_CHAR_LSHIFT:
                        MASK_CHANGE_BIT(remote_modifier_state, MapLeftShiftMask, pressed);
                        break;
                case SCANCODE_CHAR_RSHIFT:
                        MASK_CHANGE_BIT(remote_modifier_state, MapRightShiftMask, pressed);
                        break;
                case SCANCODE_CHAR_LCTRL:
                        MASK_CHANGE_BIT(remote_modifier_state, MapLeftCtrlMask, pressed);
                        break;
                case SCANCODE_CHAR_RCTRL:
                        MASK_CHANGE_BIT(remote_modifier_state, MapRightCtrlMask, pressed);
                        break;
                case SCANCODE_CHAR_LALT:
                        MASK_CHANGE_BIT(remote_modifier_state, MapLeftAltMask, pressed);
                        break;
                case SCANCODE_CHAR_RALT:
                        MASK_CHANGE_BIT(remote_modifier_state, MapRightAltMask, pressed);
                        break;
                case SCANCODE_CHAR_LWIN:
                        MASK_CHANGE_BIT(remote_modifier_state, MapLeftWinMask, pressed);
                        break;
                case SCANCODE_CHAR_RWIN:
                        MASK_CHANGE_BIT(remote_modifier_state, MapRightWinMask, pressed);
                        break;
                case SCANCODE_CHAR_NUMLOCK:
                        /* KeyReleases for NumLocks are sent immediately. Toggle the
                           modifier state only on Keypress */
                        if (pressed && !g_numlock_sync)
                        {
                                BOOL newNumLockState;
                                newNumLockState =
                                        (MASK_HAS_BITS
                                         (remote_modifier_state, MapNumLockMask) == False);
                                MASK_CHANGE_BIT(remote_modifier_state,
                                                MapNumLockMask, newNumLockState);
                        }
        }

#ifdef WITH_DEBUG_KBD
        if (old_modifier_state != remote_modifier_state)
        {
                DEBUG_KBD(("Before updating modifier_state:0x%x, pressed=0x%x\n",
                           old_modifier_state, pressed));
                DEBUG_KBD(("After updating modifier_state:0x%x\n", remote_modifier_state));
        }
#endif

}

/* Send keyboard input */
void
rdp_send_scancode(uint32 time, uint16 flags, uint8 scancode)
{
        update_modifier_state(scancode, !(flags & RDP_KEYRELEASE));

        if (scancode & SCANCODE_EXTENDED)
        {
                DEBUG_KBD(("Sending extended scancode=0x%x, flags=0x%x\n",
                           scancode & ~SCANCODE_EXTENDED, flags));
                rdp_send_input(time, RDP_INPUT_SCANCODE, flags | KBD_FLAG_EXT,
                               scancode & ~SCANCODE_EXTENDED, 0);
        }
        else
        {
                DEBUG_KBD(("Sending scancode=0x%x, flags=0x%x\n", scancode, flags));
                rdp_send_input(time, RDP_INPUT_SCANCODE, flags, scancode, 0);
        }
}