AppleWin/HookFilter/HookFilter.cpp
tomcw 140d505fe9 Keyboard:
. reverted default so that ALT+TAB is not hooked (#556)
. reverted default so that ALT GR's fake LCONTROL is not hooked (#558)
. added new switches: -hook-alt-tab and -hook-altgr-control to support hooking these key combo's (#556)
2018-07-29 22:34:09 +01:00

80 lines
2.5 KiB
C++

#include <windows.h>
static HWND g_hFrameWindow = (HWND)0;
static bool g_bHookAltTab = false;
static bool g_bHookAltGrControl = false;
// NB. __stdcall (or WINAPI) and extern "C":
// . symbol is decorated as _<symbol>@bytes
// . so use the #pragma to create an undecorated alias for our symbol
extern "C" __declspec(dllexport) LRESULT CALLBACK LowLevelKeyboardProc(
_In_ int nCode,
_In_ WPARAM wParam,
_In_ LPARAM lParam)
{
#pragma comment(linker, "/EXPORT:" __FUNCTION__ "=" __FUNCDNAME__)
if (nCode == HC_ACTION)
{
bool suppress = false;
PKBDLLHOOKSTRUCT pKbdLlHookStruct = (PKBDLLHOOKSTRUCT) lParam;
UINT newMsg = pKbdLlHookStruct->flags & LLKHF_UP ? WM_KEYUP : WM_KEYDOWN;
LPARAM newlParam = newMsg == WM_KEYUP ? 3<<30 : 0; // b31:transition state, b30:previous key state
//
// NB. Alt Gr (Right-Alt): this normally send 2 WM_KEYDOWN messages for: VK_LCONTROL, then VK_RMENU
// Keyboard scanCodes: LCONTROL=0x1D, LCONTROL_from_RMENU=0x21D
// . For: Microsoft PS/2/Win7-64, VAIO laptop/Win7-64, Microsoft USB/Win10-64
// NB. WM_KEYDOWN also includes a 9/10-bit? scanCode: LCONTROL=0x1D, RCONTROL=0x11D, RMENU=0x1D(not 0x21D)
// . Can't suppress in app, since scanCode is not >= 0x200
if (g_bHookAltGrControl && pKbdLlHookStruct->vkCode == VK_LCONTROL && pKbdLlHookStruct->scanCode >= 0x200) // GH#558
{
suppress = true;
}
// Suppress alt-tab
if (g_bHookAltTab && pKbdLlHookStruct->vkCode == VK_TAB && (pKbdLlHookStruct->flags & LLKHF_ALTDOWN))
{
PostMessage(g_hFrameWindow, newMsg, VK_TAB, newlParam);
suppress = true;
}
// Suppress alt-escape
if (pKbdLlHookStruct->vkCode == VK_ESCAPE && (pKbdLlHookStruct->flags & LLKHF_ALTDOWN))
{
PostMessage(g_hFrameWindow, newMsg, VK_ESCAPE, newlParam);
suppress = true;
}
// Suppress alt-space
if (pKbdLlHookStruct->vkCode == VK_SPACE && (pKbdLlHookStruct->flags & LLKHF_ALTDOWN))
{
PostMessage(g_hFrameWindow, newMsg, VK_SPACE, newlParam);
suppress = true;
}
// Suppress ctrl-escape
if (pKbdLlHookStruct->vkCode == VK_ESCAPE)
{
// But don't suppress CTRL+SHIFT+ESC
if (GetKeyState(VK_CONTROL) < 0 && GetKeyState(VK_SHIFT) >= 0)
suppress = true;
}
// Suppress keys by returning 1
if (suppress)
return 1;
}
return CallNextHookEx(0/*parameter is ignored*/, nCode, wParam, lParam);
}
extern "C" __declspec(dllexport) void __cdecl RegisterHWND(HWND hWnd, bool bHookAltTab, bool bHookAltGrControl)
{
g_hFrameWindow = hWnd;
g_bHookAltTab = bHookAltTab;
g_bHookAltGrControl = bHookAltGrControl;
}