KasmVNC/win/rfb_win32/WMHooks.cxx
2020-09-20 12:16:44 +00:00

387 lines
11 KiB
C++

/* Copyright (C) 2002-2005 RealVNC Ltd. All Rights Reserved.
*
* This 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 software 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 software; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307,
* USA.
*/
// -=- WMHooks.cxx
#include <os/Mutex.h>
#include <os/Thread.h>
#include <rfb_win32/WMHooks.h>
#include <rfb_win32/Service.h>
#include <rfb_win32/MsgWindow.h>
#include <rfb_win32/IntervalTimer.h>
#include <rfb/LogWriter.h>
#include <list>
using namespace rfb;
using namespace rfb::win32;
static LogWriter vlog("WMHooks");
static HMODULE hooksLibrary;
typedef UINT (*WM_Hooks_WMVAL_proto)();
static WM_Hooks_WMVAL_proto WM_Hooks_WindowChanged;
static WM_Hooks_WMVAL_proto WM_Hooks_WindowBorderChanged;
static WM_Hooks_WMVAL_proto WM_Hooks_WindowClientAreaChanged;
static WM_Hooks_WMVAL_proto WM_Hooks_RectangleChanged;
#ifdef _DEBUG
static WM_Hooks_WMVAL_proto WM_Hooks_Diagnostic;
#endif
typedef BOOL (*WM_Hooks_Install_proto)(DWORD owner, DWORD thread);
static WM_Hooks_Install_proto WM_Hooks_Install;
typedef BOOL (*WM_Hooks_Remove_proto)(DWORD owner);
static WM_Hooks_Remove_proto WM_Hooks_Remove;
#ifdef _DEBUG
typedef void (*WM_Hooks_SetDiagnosticRange_proto)(UINT min, UINT max);
static WM_Hooks_SetDiagnosticRange_proto WM_Hooks_SetDiagnosticRange;
#endif
typedef BOOL (*WM_Hooks_EnableRealInputs_proto)(BOOL pointer, BOOL keyboard);
static WM_Hooks_EnableRealInputs_proto WM_Hooks_EnableRealInputs;
static void LoadHooks()
{
if (hooksLibrary != NULL)
return;
hooksLibrary = LoadLibrary("wm_hooks.dll");
if (hooksLibrary == NULL)
return;
WM_Hooks_WindowChanged = (WM_Hooks_WMVAL_proto)GetProcAddress(hooksLibrary, "WM_Hooks_WindowChanged");
if (WM_Hooks_WindowChanged == NULL)
goto error;
WM_Hooks_WindowBorderChanged = (WM_Hooks_WMVAL_proto)GetProcAddress(hooksLibrary, "WM_Hooks_WindowBorderChanged");
if (WM_Hooks_WindowBorderChanged == NULL)
goto error;
WM_Hooks_WindowClientAreaChanged = (WM_Hooks_WMVAL_proto)GetProcAddress(hooksLibrary, "WM_Hooks_WindowClientAreaChanged");
if (WM_Hooks_WindowClientAreaChanged == NULL)
goto error;
WM_Hooks_RectangleChanged = (WM_Hooks_WMVAL_proto)GetProcAddress(hooksLibrary, "WM_Hooks_RectangleChanged");
if (WM_Hooks_RectangleChanged == NULL)
goto error;
#ifdef _DEBUG
WM_Hooks_Diagnostic = (WM_Hooks_WMVAL_proto)GetProcAddress(hooksLibrary, "WM_Hooks_Diagnostic");
if (WM_Hooks_Diagnostic == NULL)
goto error;
#endif
WM_Hooks_Install = (WM_Hooks_Install_proto)GetProcAddress(hooksLibrary, "WM_Hooks_Install");
if (WM_Hooks_Install == NULL)
goto error;
WM_Hooks_Remove = (WM_Hooks_Remove_proto)GetProcAddress(hooksLibrary, "WM_Hooks_Remove");
if (WM_Hooks_Remove == NULL)
goto error;
#ifdef _DEBUG
WM_Hooks_SetDiagnosticRange = (WM_Hooks_SetDiagnosticRange_proto)GetProcAddress(hooksLibrary, "WM_Hooks_SetDiagnosticRange");
if (WM_Hooks_SetDiagnosticRange == NULL)
goto error;
#endif
WM_Hooks_EnableRealInputs = (WM_Hooks_EnableRealInputs_proto)GetProcAddress(hooksLibrary, "WM_Hooks_EnableRealInputs");
if (WM_Hooks_EnableRealInputs == NULL)
goto error;
return;
error:
FreeLibrary(hooksLibrary);
hooksLibrary = NULL;
}
class WMHooksThread : public os::Thread {
public:
WMHooksThread() : active(true), thread_id(-1) { }
void stop();
DWORD getThreadId() { return thread_id; }
protected:
virtual void worker();
protected:
bool active;
DWORD thread_id;
};
static WMHooksThread* hook_mgr = 0;
static std::list<WMHooks*> hooks;
static os::Mutex hook_mgr_lock;
static bool StartHookThread() {
if (hook_mgr)
return true;
if (hooksLibrary == NULL)
return false;
vlog.debug("creating thread");
hook_mgr = new WMHooksThread();
hook_mgr->start();
while (hook_mgr->getThreadId() == (DWORD)-1)
Sleep(0);
vlog.debug("installing hooks");
if (!WM_Hooks_Install(hook_mgr->getThreadId(), 0)) {
vlog.error("failed to initialise hooks");
hook_mgr->stop();
delete hook_mgr;
hook_mgr = 0;
return false;
}
return true;
}
static void StopHookThread() {
if (!hook_mgr)
return;
if (!hooks.empty())
return;
vlog.debug("closing thread");
hook_mgr->stop();
delete hook_mgr;
hook_mgr = 0;
}
static bool AddHook(WMHooks* hook) {
vlog.debug("adding hook");
os::AutoMutex a(&hook_mgr_lock);
if (!StartHookThread())
return false;
hooks.push_back(hook);
return true;
}
static bool RemHook(WMHooks* hook) {
{
vlog.debug("removing hook");
os::AutoMutex a(&hook_mgr_lock);
hooks.remove(hook);
}
StopHookThread();
return true;
}
static void NotifyHooksRegion(const Region& r) {
os::AutoMutex a(&hook_mgr_lock);
std::list<WMHooks*>::iterator i;
for (i=hooks.begin(); i!=hooks.end(); i++)
(*i)->NotifyHooksRegion(r);
}
void
WMHooksThread::worker() {
// Obtain message ids for all supported hook messages
UINT windowMsg = WM_Hooks_WindowChanged();
UINT clientAreaMsg = WM_Hooks_WindowClientAreaChanged();
UINT borderMsg = WM_Hooks_WindowBorderChanged();
UINT rectangleMsg = WM_Hooks_RectangleChanged();
#ifdef _DEBUG
UINT diagnosticMsg = WM_Hooks_Diagnostic();
#endif
MSG msg;
RECT wrect;
HWND hwnd;
int count = 0;
// Update delay handling
// We delay updates by 40-80ms, so that the triggering application has time to
// actually complete them before we notify the hook callbacks & they go off
// capturing screen state.
const int updateDelayMs = 40;
MsgWindow updateDelayWnd(_T("WMHooks::updateDelay"));
IntervalTimer updateDelayTimer(updateDelayWnd.getHandle(), 1);
Region updates[2];
int activeRgn = 0;
vlog.debug("starting hook thread");
thread_id = GetCurrentThreadId();
while (active && GetMessage(&msg, NULL, 0, 0)) {
count++;
if (msg.message == WM_TIMER) {
// Actually notify callbacks of graphical updates
NotifyHooksRegion(updates[1-activeRgn]);
if (updates[activeRgn].is_empty())
updateDelayTimer.stop();
activeRgn = 1-activeRgn;
updates[activeRgn].clear();
} else if (msg.message == windowMsg) {
// An entire window has (potentially) changed
hwnd = (HWND) msg.lParam;
if (IsWindow(hwnd) && IsWindowVisible(hwnd) && !IsIconic(hwnd) &&
GetWindowRect(hwnd, &wrect) && !IsRectEmpty(&wrect)) {
updates[activeRgn].assign_union(Rect(wrect.left, wrect.top,
wrect.right, wrect.bottom));
updateDelayTimer.start(updateDelayMs);
}
} else if (msg.message == clientAreaMsg) {
// The client area of a window has (potentially) changed
hwnd = (HWND) msg.lParam;
if (IsWindow(hwnd) && IsWindowVisible(hwnd) && !IsIconic(hwnd) &&
GetClientRect(hwnd, &wrect) && !IsRectEmpty(&wrect))
{
POINT pt = {0,0};
if (ClientToScreen(hwnd, &pt)) {
updates[activeRgn].assign_union(Rect(wrect.left+pt.x, wrect.top+pt.y,
wrect.right+pt.x, wrect.bottom+pt.y));
updateDelayTimer.start(updateDelayMs);
}
}
} else if (msg.message == borderMsg) {
hwnd = (HWND) msg.lParam;
if (IsWindow(hwnd) && IsWindowVisible(hwnd) && !IsIconic(hwnd) &&
GetWindowRect(hwnd, &wrect) && !IsRectEmpty(&wrect))
{
Region changed(Rect(wrect.left, wrect.top, wrect.right, wrect.bottom));
RECT crect;
POINT pt = {0,0};
if (GetClientRect(hwnd, &crect) && ClientToScreen(hwnd, &pt) &&
!IsRectEmpty(&crect))
{
changed.assign_subtract(Rect(crect.left+pt.x, crect.top+pt.y,
crect.right+pt.x, crect.bottom+pt.y));
}
if (!changed.is_empty()) {
updates[activeRgn].assign_union(changed);
updateDelayTimer.start(updateDelayMs);
}
}
} else if (msg.message == rectangleMsg) {
Rect r = Rect(LOWORD(msg.wParam), HIWORD(msg.wParam),
LOWORD(msg.lParam), HIWORD(msg.lParam));
if (!r.is_empty()) {
updates[activeRgn].assign_union(r);
updateDelayTimer.start(updateDelayMs);
}
#ifdef _DEBUG
} else if (msg.message == diagnosticMsg) {
vlog.info("DIAG msg=%x(%d) wnd=%lx",
(unsigned)msg.wParam, (int)msg.wParam,
(unsigned long)msg.lParam);
#endif
}
}
vlog.debug("stopping hook thread - processed %d events", count);
WM_Hooks_Remove(getThreadId());
}
void
WMHooksThread::stop() {
vlog.debug("stopping WMHooks thread");
active = false;
PostThreadMessage(thread_id, WM_QUIT, 0, 0);
vlog.debug("waiting for WMHooks thread");
wait();
}
// -=- WMHooks class
rfb::win32::WMHooks::WMHooks() : updateEvent(0) {
LoadHooks();
}
rfb::win32::WMHooks::~WMHooks() {
RemHook(this);
}
bool rfb::win32::WMHooks::setEvent(HANDLE ue) {
if (updateEvent)
RemHook(this);
updateEvent = ue;
return AddHook(this);
}
bool rfb::win32::WMHooks::getUpdates(UpdateTracker* ut) {
if (!updatesReady) return false;
os::AutoMutex a(&hook_mgr_lock);
updates.copyTo(ut);
updates.clear();
updatesReady = false;
return true;
}
#ifdef _DEBUG
void
rfb::win32::WMHooks::setDiagnosticRange(UINT min, UINT max) {
WM_Hooks_SetDiagnosticRange(min, max);
}
#endif
void rfb::win32::WMHooks::NotifyHooksRegion(const Region& r) {
// hook_mgr_lock is already held at this point
updates.add_changed(r);
updatesReady = true;
SetEvent(updateEvent);
}
// -=- WMBlockInput class
rfb::win32::WMBlockInput::WMBlockInput() : active(false) {
LoadHooks();
}
rfb::win32::WMBlockInput::~WMBlockInput() {
blockInputs(false);
}
static bool blocking = false;
static bool blockRealInputs(bool block_) {
// NB: Requires blockMutex to be held!
if (hooksLibrary == NULL)
return false;
if (block_) {
if (blocking)
return true;
// Enable blocking
if (!WM_Hooks_EnableRealInputs(false, false))
return false;
blocking = true;
}
if (blocking) {
WM_Hooks_EnableRealInputs(true, true);
blocking = false;
}
return block_ == blocking;
}
static os::Mutex blockMutex;
static int blockCount = 0;
bool rfb::win32::WMBlockInput::blockInputs(bool on) {
if (active == on) return true;
os::AutoMutex a(&blockMutex);
int newCount = on ? blockCount+1 : blockCount-1;
if (!blockRealInputs(newCount > 0))
return false;
blockCount = newCount;
active = on;
return true;
}