qemu/ui/win32-kbd-hook.c
Volker Rümelin 2df9f5718d ui/win32-kbd-hook: handle AltGr in a hook procedure
Import win32 keyboard hooking code from project spice-gtk. This
patch removes the extra left control key up/down input events
inserted by Windows for the right alt key up/down input events
with international keyboard layouts. Additionally there's some
code to grab the keyboard.

The next patches will use this code.

Only Windows needs this.

Signed-off-by: Volker Rümelin <vr_qemu@t-online.de>
Message-id: 20200516072014.7766-1-vr_qemu@t-online.de
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
2020-05-19 09:06:44 +02:00

103 lines
2.9 KiB
C

/*
* This work is licensed under the terms of the GNU GPL, version 2 or
* (at your option) any later version. See the COPYING file in the
* top-level directory.
*
* The win32 keyboard hooking code was imported from project spice-gtk.
*/
#include "qemu/osdep.h"
#include "sysemu/sysemu.h"
#include "ui/win32-kbd-hook.h"
static Notifier win32_unhook_notifier;
static HHOOK win32_keyboard_hook;
static HWND win32_window;
static DWORD win32_grab;
static LRESULT CALLBACK keyboard_hook_cb(int code, WPARAM wparam, LPARAM lparam)
{
if (win32_window && code == HC_ACTION && win32_window == GetFocus()) {
KBDLLHOOKSTRUCT *hooked = (KBDLLHOOKSTRUCT *)lparam;
if (wparam != WM_KEYUP) {
DWORD dwmsg = (hooked->flags << 24) |
((hooked->scanCode & 0xff) << 16) | 1;
switch (hooked->vkCode) {
case VK_CAPITAL:
/* fall through */
case VK_SCROLL:
/* fall through */
case VK_NUMLOCK:
/* fall through */
case VK_LSHIFT:
/* fall through */
case VK_RSHIFT:
/* fall through */
case VK_RCONTROL:
/* fall through */
case VK_LMENU:
/* fall through */
case VK_RMENU:
break;
case VK_LCONTROL:
/*
* When pressing AltGr, an extra VK_LCONTROL with a special
* scancode with bit 9 set is sent. Let's ignore the extra
* VK_LCONTROL, as that will make AltGr misbehave.
*/
if (hooked->scanCode & 0x200) {
return 1;
}
break;
default:
if (win32_grab) {
SendMessage(win32_window, wparam, hooked->vkCode, dwmsg);
return 1;
}
break;
}
} else {
switch (hooked->vkCode) {
case VK_LCONTROL:
if (hooked->scanCode & 0x200) {
return 1;
}
break;
}
}
}
return CallNextHookEx(NULL, code, wparam, lparam);
}
static void keyboard_hook_unhook(Notifier *n, void *data)
{
UnhookWindowsHookEx(win32_keyboard_hook);
win32_keyboard_hook = NULL;
}
void win32_kbd_set_window(void *hwnd)
{
if (hwnd && !win32_keyboard_hook) {
/* note: the installing thread must have a message loop */
win32_keyboard_hook = SetWindowsHookEx(WH_KEYBOARD_LL, keyboard_hook_cb,
GetModuleHandle(NULL), 0);
if (win32_keyboard_hook) {
win32_unhook_notifier.notify = keyboard_hook_unhook;
qemu_add_exit_notifier(&win32_unhook_notifier);
}
}
win32_window = hwnd;
}
void win32_kbd_set_grab(bool grab)
{
win32_grab = grab;
}