Merge pull request #6596 from symless/v1-issue-4957-remove-synwinhk

Removed Windows hook DLL

dist/wix/Product.wxs

@@ -97,7 +97,6 @@
 				</File>
 				<File Source="$(var.BinPath)/synergyc.exe"/>
 				<File Source="$(var.BinPath)/syntool.exe"/>
-				<File Source="$(var.BinPath)/synwinhk.dll"/>
         <?if $(var.Platform) = x64 ?>
 				  <File Source="$(var.OpenSSLBinPath)/libssl-1_1-x64.dll"/>
 				  <File Source="$(var.OpenSSLBinPath)/libcrypto-1_1-x64.dll"/>

src/lib/CMakeLists.txt

@@ -26,7 +26,3 @@ add_subdirectory(platform)
 add_subdirectory(server)
 add_subdirectory(synergy)
 add_subdirectory(shared)
-
-if (WIN32)
-    add_subdirectory(synwinhk)
-endif()

src/lib/platform/MSWindowsDesks.cpp

@@ -18,7 +18,7 @@
 
 #include "platform/MSWindowsDesks.h"
 
-#include "synwinhk/synwinhk.h"
+#include "platform/synwinhk.h"
 #include "platform/MSWindowsScreen.h"
 #include "synergy/IScreenSaver.h"
 #include "synergy/XScreen.h"
@@ -93,7 +93,7 @@
 //
 
 MSWindowsDesks::MSWindowsDesks(
-        bool isPrimary, bool noHooks, HINSTANCE hookLibrary,
+        bool isPrimary, bool noHooks,
         const IScreenSaver* screensaver, IEventQueue* events,
         IJob* updateKeys, bool stopOnDeskSwitch) :
     m_isPrimary(isPrimary),
@@ -114,8 +114,6 @@ MSWindowsDesks::MSWindowsDesks(
     m_events(events),
     m_stopOnDeskSwitch(stopOnDeskSwitch)
 {
-    if (hookLibrary != NULL)
-        queryHookLibrary(hookLibrary);
 
     m_cursor    = createBlankCursor();
     m_deskClass = createDeskWindowClass(m_isPrimary);
@@ -348,35 +346,6 @@ MSWindowsDesks::sendMessage(UINT msg, WPARAM wParam, LPARAM lParam) const
     }
 }
 
-void
-MSWindowsDesks::queryHookLibrary(HINSTANCE hookLibrary)
-{
-    // look up functions
-    if (m_isPrimary && !m_noHooks) {
-        m_install   = (InstallFunc)GetProcAddress(hookLibrary, "install");
-        m_uninstall = (UninstallFunc)GetProcAddress(hookLibrary, "uninstall");
-        m_installScreensaver   =
-                  (InstallScreenSaverFunc)GetProcAddress(
-                                hookLibrary, "installScreenSaver");
-        m_uninstallScreensaver =
-                  (UninstallScreenSaverFunc)GetProcAddress(
-                                hookLibrary, "uninstallScreenSaver");
-        if (m_install              == NULL ||
-            m_uninstall            == NULL ||
-            m_installScreensaver   == NULL ||
-            m_uninstallScreensaver == NULL) {
-            LOG((CLOG_ERR "Invalid hook library"));
-            throw XScreenOpenFailure();
-        }
-    }
-    else {
-        m_install              = NULL;
-        m_uninstall            = NULL;
-        m_installScreensaver   = NULL;
-        m_uninstallScreensaver = NULL;
-    }
-}
-
 HCURSOR
 MSWindowsDesks::createBlankCursor() const
 {
@@ -690,13 +659,13 @@ MSWindowsDesks::deskThread(void* vdesk)
             continue;
 
         case SYNERGY_MSG_SWITCH:
-            if (m_isPrimary && !m_noHooks) {
+            if (!m_noHooks) {
-                m_uninstall();
+                MSWindowsHook::uninstall();
                 if (m_screensaverNotify) {
-                    m_uninstallScreensaver();
+                    MSWindowsHook::uninstallScreenSaver();
-                    m_installScreensaver();
+                    MSWindowsHook::installScreenSaver();
                 }
-                switch (m_install()) {
+                switch (MSWindowsHook::install()) {
                 case kHOOK_FAILED:
                     // we won't work on this desk
                     desk->m_lowLevel = false;
@@ -772,10 +741,10 @@ MSWindowsDesks::deskThread(void* vdesk)
         case SYNERGY_MSG_SCREENSAVER:
             if (!m_noHooks) {
                 if (msg.wParam != 0) {
-                    m_installScreensaver();
+                    MSWindowsHook::installScreenSaver();
                 }
                 else {
-                    m_uninstallScreensaver();
+                    MSWindowsHook::uninstallScreenSaver();
                 }
             }
             break;

src/lib/platform/MSWindowsDesks.h

@@ -18,7 +18,7 @@
 
 #pragma once
 
-#include "synwinhk/synwinhk.h"
+#include "platform/synwinhk.h"
 #include "synergy/key_types.h"
 #include "synergy/mouse_types.h"
 #include "synergy/option_types.h"
@@ -65,7 +65,7 @@ public:
     \p hookLibrary must be a handle to the hook library.
     */
     MSWindowsDesks(
-        bool isPrimary, bool noHooks, HINSTANCE hookLibrary,
+        bool isPrimary, bool noHooks,
         const IScreenSaver* screensaver, IEventQueue* events,
         IJob* updateKeys, bool stopOnDeskSwitch);
     ~MSWindowsDesks();
@@ -206,7 +206,6 @@ private:
     typedef std::map<String, Desk*> Desks;
 
     // initialization and shutdown operations
-    void                queryHookLibrary(HINSTANCE hookLibrary);
     HCURSOR                createBlankCursor() const;
     void                destroyCursor(HCURSOR cursor) const;
     ATOM                createDeskWindowClass(bool isPrimary) const;
@@ -283,14 +282,6 @@ private:
     CondVar<bool>        m_deskReady;
     Desks                m_desks;
 
-    // hook library stuff
-    InstallFunc            m_install;
-    UninstallFunc        m_uninstall;
-    InstallScreenSaverFunc
-                        m_installScreensaver;
-    UninstallScreenSaverFunc
-                        m_uninstallScreensaver;
-
     // keyboard stuff
     IJob*                m_updateKeys;
     HKL                    m_keyLayout;

src/lib/platform/MSWindowsHook.cpp

@@ -17,19 +17,35 @@
  */
 
 #include "platform/MSWindowsHook.h"
-
+#include "synergy/protocol_types.h"
 #include "synergy/XScreen.h"
 #include "base/Log.h"
 
 static const char* g_name = "synwinhk";
 
-MSWindowsHook::MSWindowsHook() :
+static DWORD            g_processID       = 0;
-    m_initFunc(NULL),
+static DWORD            g_threadID        = 0;
-    m_cleanupFunc(NULL),
+static HHOOK            g_getMessage      = NULL;
-    m_setSidesFunc(NULL),
+static HHOOK            g_keyboardLL      = NULL;
-    m_setZoneFunc(NULL),
+static HHOOK            g_mouseLL         = NULL;
-    m_setModeFunc(NULL),
+static bool                g_screenSaver     = false;
-    m_instance(NULL)
+static EHookMode        g_mode            = kHOOK_DISABLE;
+static UInt32            g_zoneSides       = 0;
+static SInt32            g_zoneSize        = 0;
+static SInt32            g_xScreen         = 0;
+static SInt32            g_yScreen         = 0;
+static SInt32            g_wScreen         = 0;
+static SInt32            g_hScreen         = 0;
+static WPARAM            g_deadVirtKey     = 0;
+static WPARAM            g_deadRelease     = 0;
+static LPARAM            g_deadLParam      = 0;
+static BYTE                g_deadKeyState[256] = { 0 };
+static BYTE                g_keyState[256]   = { 0 };
+static DWORD            g_hookThread      = 0;
+static bool                g_fakeServerInput       = false;
+static BOOL				g_isPrimary = TRUE;
+
+MSWindowsHook::MSWindowsHook()
 {
 }
 
@@ -37,35 +53,18 @@ MSWindowsHook::~MSWindowsHook()
 {
     cleanup();
 
-    if (m_instance != NULL) {
+    if (g_processID == GetCurrentProcessId()) {
-        FreeLibrary(m_instance);
+        uninstall();
+        uninstallScreenSaver();
+        g_processID = 0;
     }
 }
 
 void
 MSWindowsHook::loadLibrary()
 {
-    // load library
+    if (g_processID == 0) {
-    m_instance = LoadLibrary(g_name);
+        g_processID = GetCurrentProcessId();
-    if (m_instance == NULL) {
-        LOG((CLOG_ERR "failed to load hook library, %s.dll is missing or invalid", g_name));
-        throw XScreenOpenFailure();
-    }
-
-    // look up functions
-    m_setSidesFunc = (SetSidesFunc)GetProcAddress(m_instance, "setSides");
-    m_setZoneFunc = (SetZoneFunc)GetProcAddress(m_instance, "setZone");
-    m_setModeFunc = (SetModeFunc)GetProcAddress(m_instance, "setMode");
-    m_initFunc = (InitFunc)GetProcAddress(m_instance, "init");
-    m_cleanupFunc = (CleanupFunc)GetProcAddress(m_instance, "cleanup");
-
-    if (m_setSidesFunc == NULL ||
-        m_setZoneFunc == NULL ||
-        m_setModeFunc == NULL ||
-        m_initFunc == NULL ||
-        m_cleanupFunc == NULL) {
-        LOG((CLOG_ERR "failed to load hook function, %s.dll could be out of date", g_name));
-        throw XScreenOpenFailure();
     }
 
     // initialize library
@@ -76,53 +75,703 @@ MSWindowsHook::loadLibrary()
     }
 }
 
-HINSTANCE
-MSWindowsHook::getInstance() const
-{
-    return m_instance;
-}
-
 int
 MSWindowsHook::init(DWORD threadID)
 {
-    if (m_initFunc == NULL) {
+    // try to open process that last called init() to see if it's
-        return NULL;
+    // still running or if it died without cleaning up.
+    if (g_processID != 0 && g_processID != GetCurrentProcessId()) {
+        HANDLE process = OpenProcess(STANDARD_RIGHTS_REQUIRED,
+                                FALSE, g_processID);
+        if (process != NULL) {
+            // old process (probably) still exists so refuse to
+            // reinitialize this DLL (and thus steal it from the
+            // old process).
+            int result = CloseHandle(process);
+            if (result == false) {
+                return 0;
             }
-    return m_initFunc(threadID);
+        }
+
+        // clean up after old process.  the system should've already
+        // removed the hooks so we just need to reset our state.
+        g_processID       = GetCurrentProcessId();
+        g_threadID        = 0;
+        g_getMessage      = NULL;
+        g_keyboardLL      = NULL;
+        g_mouseLL         = NULL;
+        g_screenSaver     = false;
+    }
+
+    // save thread id.  we'll post messages to this thread's
+    // message queue.
+    g_threadID  = threadID;
+
+    // set defaults
+    g_mode      = kHOOK_DISABLE;
+    g_zoneSides = 0;
+    g_zoneSize  = 0;
+    g_xScreen   = 0;
+    g_yScreen   = 0;
+    g_wScreen   = 0;
+    g_hScreen   = 0;
+
+    return 1;
 }
 
 int
 MSWindowsHook::cleanup()
 {
-    if (m_cleanupFunc == NULL) {
+    if (g_processID == GetCurrentProcessId()) {
-        return NULL;
+        g_threadID = 0;
     }
-    return m_cleanupFunc();
+
+    return 1;
 }
 
 void
 MSWindowsHook::setSides(UInt32 sides)
 {
-    if (m_setSidesFunc == NULL) {
+    g_zoneSides = sides;
-        return;
-    }
-    m_setSidesFunc(sides);
 }
 
 void
 MSWindowsHook::setZone(SInt32 x, SInt32 y, SInt32 w, SInt32 h, SInt32 jumpZoneSize)
 {
-    if (m_setZoneFunc == NULL) {
+    g_zoneSize = jumpZoneSize;
-        return;
+    g_xScreen  = x;
-    }
+    g_yScreen  = y;
-    m_setZoneFunc(x, y, w, h, jumpZoneSize);
+    g_wScreen  = w;
+    g_hScreen  = h;
 }
 
 void
 MSWindowsHook::setMode(EHookMode mode)
 {
-    if (m_setModeFunc == NULL) {
+    if (mode == g_mode) {
+        // no change
         return;
     }
-    m_setModeFunc(mode);
+    g_mode = mode;
+}
+
+static
+void
+keyboardGetState(BYTE keys[256], DWORD vkCode, bool kf_up)
+{
+    // we have to use GetAsyncKeyState() rather than GetKeyState() because
+    // we don't pass through most keys so the event synchronous state
+    // doesn't get updated.  we do that because certain modifier keys have
+    // side effects, like alt and the windows key.
+    if (vkCode < 0 || vkCode >= 256) {
+        return;
+    }
+
+    // Keep track of key state on our own in case GetAsyncKeyState() fails
+    g_keyState[vkCode] = kf_up ? 0 : 0x80;
+    g_keyState[VK_SHIFT] = g_keyState[VK_LSHIFT] | g_keyState[VK_RSHIFT];
+
+    SHORT key;
+    // Test whether GetAsyncKeyState() is being honest with us
+    key = GetAsyncKeyState(vkCode);
+
+    if (key & 0x80) {
+        // The only time we know for sure that GetAsyncKeyState() is working
+        // is when it tells us that the current key is down.
+        // In this case, update g_keyState to reflect what GetAsyncKeyState()
+        // is telling us, just in case we have gotten out of sync
+
+        for (int i = 0; i < 256; ++i) {
+            key = GetAsyncKeyState(i);
+            g_keyState[i] = (BYTE)((key < 0) ? 0x80u : 0);
+        }
+    }
+
+    // copy g_keyState to keys
+    for (int i = 0; i < 256; ++i) {
+        keys[i] = g_keyState[i];
+    }
+
+    key = GetKeyState(VK_CAPITAL);
+    keys[VK_CAPITAL] = (BYTE)(((key < 0) ? 0x80 : 0) | (key & 1));
+}
+
+static
+WPARAM
+makeKeyMsg(UINT virtKey, char c, bool noAltGr)
+{
+    return MAKEWPARAM(MAKEWORD(virtKey & 0xff, (BYTE)c), noAltGr ? 1 : 0);
+}
+
+static
+bool
+keyboardHookHandler(WPARAM wParam, LPARAM lParam)
+{
+    DWORD vkCode = static_cast<DWORD>(wParam);
+    bool kf_up = (lParam & (KF_UP << 16)) != 0;
+
+    // check for special events indicating if we should start or stop
+    // passing events through and not report them to the server.  this
+    // is used to allow the server to synthesize events locally but
+    // not pick them up as user events.
+    if (wParam == SYNERGY_HOOK_FAKE_INPUT_VIRTUAL_KEY &&
+        ((lParam >> 16) & 0xffu) == SYNERGY_HOOK_FAKE_INPUT_SCANCODE) {
+        // update flag
+        g_fakeServerInput = ((lParam & 0x80000000u) == 0);
+        PostThreadMessage(g_threadID, SYNERGY_MSG_DEBUG,
+                                0xff000000u | wParam, lParam);
+
+        // discard event
+        return true;
+    }
+
+    // if we're expecting fake input then just pass the event through
+    // and do not forward to the server
+    if (g_fakeServerInput) {
+        PostThreadMessage(g_threadID, SYNERGY_MSG_DEBUG,
+                                0xfe000000u | wParam, lParam);
+        return false;
+    }
+
+    // VK_RSHIFT may be sent with an extended scan code but right shift
+    // is not an extended key so we reset that bit.
+    if (wParam == VK_RSHIFT) {
+        lParam &= ~0x01000000u;
+    }
+
+    // tell server about event
+    PostThreadMessage(g_threadID, SYNERGY_MSG_DEBUG, wParam, lParam);
+
+    // ignore dead key release
+    if ((g_deadVirtKey == wParam || g_deadRelease == wParam) &&
+        (lParam & 0x80000000u) != 0) {
+        g_deadRelease = 0;
+        PostThreadMessage(g_threadID, SYNERGY_MSG_DEBUG,
+                        wParam | 0x04000000, lParam);
+        return false;
+    }
+
+    // we need the keyboard state for ToAscii()
+    BYTE keys[256];
+    keyboardGetState(keys, vkCode, kf_up);
+
+    // ToAscii() maps ctrl+letter to the corresponding control code
+    // and ctrl+backspace to delete.  we don't want those translations
+    // so clear the control modifier state.  however, if we want to
+    // simulate AltGr (which is ctrl+alt) then we must not clear it.
+    UINT control = keys[VK_CONTROL] | keys[VK_LCONTROL] | keys[VK_RCONTROL];
+    UINT menu    = keys[VK_MENU] | keys[VK_LMENU] | keys[VK_RMENU];
+    if ((control & 0x80) == 0 || (menu & 0x80) == 0) {
+        keys[VK_LCONTROL] = 0;
+        keys[VK_RCONTROL] = 0;
+        keys[VK_CONTROL]  = 0;
+    }
+    else {
+        keys[VK_LCONTROL] = 0x80;
+        keys[VK_RCONTROL] = 0x80;
+        keys[VK_CONTROL]  = 0x80;
+        keys[VK_LMENU]    = 0x80;
+        keys[VK_RMENU]    = 0x80;
+        keys[VK_MENU]     = 0x80;
+    }
+
+    // ToAscii() needs to know if a menu is active for some reason.
+    // we don't know and there doesn't appear to be any way to find
+    // out.  so we'll just assume a menu is active if the menu key
+    // is down.
+    // FIXME -- figure out some way to check if a menu is active
+    UINT flags = 0;
+    if ((menu & 0x80) != 0)
+        flags |= 1;
+
+    // if we're on the server screen then just pass numpad keys with alt
+    // key down as-is.  we won't pick up the resulting character but the
+    // local app will.  if on a client screen then grab keys as usual;
+    // if the client is a windows system it'll synthesize the expected
+    // character.  if not then it'll probably just do nothing.
+    if (g_mode != kHOOK_RELAY_EVENTS) {
+        // we don't use virtual keys because we don't know what the
+        // state of the numlock key is.  we'll hard code the scan codes
+        // instead.  hopefully this works across all keyboards.
+        UINT sc = (lParam & 0x01ff0000u) >> 16;
+        if (menu &&
+            (sc >= 0x47u && sc <= 0x52u && sc != 0x4au && sc != 0x4eu)) {
+            return false;
+        }
+    }
+
+    WORD c        = 0;
+
+    // map the key event to a character.  we have to put the dead
+    // key back first and this has the side effect of removing it.
+    if (g_deadVirtKey != 0) {
+        if (ToAscii((UINT)g_deadVirtKey, (g_deadLParam & 0x10ff0000u) >> 16,
+                    g_deadKeyState, &c, flags) == 2)
+        {
+            // If ToAscii returned 2, it means that we accidentally removed
+            // a double dead key instead of restoring it. Thus, we call
+            // ToAscii again with the same parameters to restore the
+            // internal dead key state.
+            ToAscii((UINT)g_deadVirtKey, (g_deadLParam & 0x10ff0000u) >> 16,
+                    g_deadKeyState, &c, flags);
+
+            // We need to keep track of this because g_deadVirtKey will be
+            // cleared later on; this would cause the dead key release to
+            // incorrectly restore the dead key state.
+            g_deadRelease = g_deadVirtKey;
+        }
+    }
+
+    UINT scanCode = ((lParam & 0x10ff0000u) >> 16);
+    int n         = ToAscii((UINT)wParam, scanCode, keys, &c, flags);
+
+    // if mapping failed and ctrl and alt are pressed then try again
+    // with both not pressed.  this handles the case where ctrl and
+    // alt are being used as individual modifiers rather than AltGr.
+    // we note that's the case in the message sent back to synergy
+    // because there's no simple way to deduce it after the fact.
+    // we have to put the dead key back first, if there was one.
+    bool noAltGr = false;
+    if (n == 0 && (control & 0x80) != 0 && (menu & 0x80) != 0) {
+        noAltGr = true;
+        PostThreadMessage(g_threadID, SYNERGY_MSG_DEBUG,
+                            wParam | 0x05000000, lParam);
+        if (g_deadVirtKey != 0) {
+            if (ToAscii((UINT)g_deadVirtKey, (g_deadLParam & 0x10ff0000u) >> 16,
+                            g_deadKeyState, &c, flags) == 2)
+            {
+                ToAscii((UINT)g_deadVirtKey, (g_deadLParam & 0x10ff0000u) >> 16,
+                            g_deadKeyState, &c, flags);
+                g_deadRelease = g_deadVirtKey;
+            }
+        }
+        BYTE keys2[256];
+        for (size_t i = 0; i < sizeof(keys) / sizeof(keys[0]); ++i) {
+            keys2[i] = keys[i];
+        }
+        keys2[VK_LCONTROL] = 0;
+        keys2[VK_RCONTROL] = 0;
+        keys2[VK_CONTROL]  = 0;
+        keys2[VK_LMENU]    = 0;
+        keys2[VK_RMENU]    = 0;
+        keys2[VK_MENU]     = 0;
+        n = ToAscii((UINT)wParam, scanCode, keys2, &c, flags);
+    }
+
+    PostThreadMessage(g_threadID, SYNERGY_MSG_DEBUG,
+                            wParam | ((c & 0xff) << 8) |
+                            ((n & 0xff) << 16) | 0x06000000,
+                            lParam);
+    WPARAM charAndVirtKey = 0;
+    bool clearDeadKey = false;
+    switch (n) {
+    default:
+        // key is a dead key
+
+        if (lParam & 0x80000000u)
+            // This handles the obscure situation where a key has been
+            // pressed which is both a dead key and a normal character
+            // depending on which modifiers have been pressed. We
+            // break here to prevent it from being considered a dead
+            // key.
+            break;
+
+        g_deadVirtKey = wParam;
+        g_deadLParam  = lParam;
+        for (size_t i = 0; i < sizeof(keys) / sizeof(keys[0]); ++i) {
+            g_deadKeyState[i] = keys[i];
+        }
+        break;
+
+    case 0:
+        // key doesn't map to a character.  this can happen if
+        // non-character keys are pressed after a dead key.
+        charAndVirtKey = makeKeyMsg((UINT)wParam, (char)0, noAltGr);
+        break;
+
+    case 1:
+        // key maps to a character composed with dead key
+        charAndVirtKey = makeKeyMsg((UINT)wParam, (char)LOBYTE(c), noAltGr);
+        clearDeadKey   = true;
+        break;
+
+    case 2: {
+        // previous dead key not composed.  send a fake key press
+        // and release for the dead key to our window.
+        WPARAM deadCharAndVirtKey =
+                            makeKeyMsg((UINT)g_deadVirtKey, (char)LOBYTE(c), noAltGr);
+        PostThreadMessage(g_threadID, SYNERGY_MSG_KEY,
+                            deadCharAndVirtKey, g_deadLParam & 0x7fffffffu);
+        PostThreadMessage(g_threadID, SYNERGY_MSG_KEY,
+                            deadCharAndVirtKey, g_deadLParam | 0x80000000u);
+
+        // use uncomposed character
+        charAndVirtKey = makeKeyMsg((UINT)wParam, (char)HIBYTE(c), noAltGr);
+        clearDeadKey   = true;
+        break;
+    }
+    }
+
+    // put back the dead key, if any, for the application to use
+    if (g_deadVirtKey != 0) {
+        ToAscii((UINT)g_deadVirtKey, (g_deadLParam & 0x10ff0000u) >> 16,
+                            g_deadKeyState, &c, flags);
+    }
+
+    // clear out old dead key state
+    if (clearDeadKey) {
+        g_deadVirtKey = 0;
+        g_deadLParam  = 0;
+    }
+
+    // forward message to our window.  do this whether or not we're
+    // forwarding events to clients because this'll keep our thread's
+    // key state table up to date.  that's important for querying
+    // the scroll lock toggle state.
+    // XXX -- with hot keys for actions we may only need to do this when
+    // forwarding.
+    if (charAndVirtKey != 0) {
+        PostThreadMessage(g_threadID, SYNERGY_MSG_DEBUG,
+                            charAndVirtKey | 0x07000000, lParam);
+        PostThreadMessage(g_threadID, SYNERGY_MSG_KEY, charAndVirtKey, lParam);
+    }
+
+    if (g_mode == kHOOK_RELAY_EVENTS) {
+        // let certain keys pass through
+        switch (wParam) {
+        case VK_CAPITAL:
+        case VK_NUMLOCK:
+        case VK_SCROLL:
+            // pass event on.  we want to let these through to
+            // the window proc because otherwise the keyboard
+            // lights may not stay synchronized.
+            break;
+
+        case VK_HANGUL:
+            // pass these modifiers if using a low level hook, discard
+            // them if not.
+            if (g_hookThread == 0) {
+                return true;
+            }
+            break;
+
+        default:
+            // discard
+            return true;
+        }
+    }
+
+    return false;
+}
+
+
+#if !NO_GRAB_KEYBOARD
+static
+LRESULT CALLBACK
+keyboardLLHook(int code, WPARAM wParam, LPARAM lParam)
+{
+    if (code >= 0) {
+        // decode the message
+        KBDLLHOOKSTRUCT* info = reinterpret_cast<KBDLLHOOKSTRUCT*>(lParam);
+
+        bool const injected = info->flags & LLKHF_INJECTED;
+        if (!g_isPrimary && injected) {
+            return CallNextHookEx (g_keyboardLL, code, wParam, lParam);
+        }
+
+        WPARAM wParam = info->vkCode;
+        LPARAM lParam = 1;                            // repeat code
+        lParam      |= (info->scanCode << 16);        // scan code
+        if (info->flags & LLKHF_EXTENDED) {
+            lParam  |= (1lu << 24);                    // extended key
+        }
+        if (info->flags & LLKHF_ALTDOWN) {
+            lParam  |= (1lu << 29);                    // context code
+        }
+        if (info->flags & LLKHF_UP) {
+            lParam  |= (1lu << 31);                    // transition
+        }
+        // FIXME -- bit 30 should be set if key was already down but
+        // we don't know that info.  as a result we'll never generate
+        // key repeat events.
+
+        // handle the message
+        if (keyboardHookHandler(wParam, lParam)) {
+            return 1;
+        }
+    }
+
+    return CallNextHookEx(g_keyboardLL, code, wParam, lParam);
+}
+#endif
+
+//
+// low-level mouse hook -- this allows us to capture and handle mouse
+// events very early.  the earlier the better.
+//
+
+static
+bool
+mouseHookHandler(WPARAM wParam, SInt32 x, SInt32 y, SInt32 data)
+{
+    switch (wParam) {
+    case WM_LBUTTONDOWN:
+    case WM_MBUTTONDOWN:
+    case WM_RBUTTONDOWN:
+    case WM_XBUTTONDOWN:
+    case WM_LBUTTONDBLCLK:
+    case WM_MBUTTONDBLCLK:
+    case WM_RBUTTONDBLCLK:
+    case WM_XBUTTONDBLCLK:
+    case WM_LBUTTONUP:
+    case WM_MBUTTONUP:
+    case WM_RBUTTONUP:
+    case WM_XBUTTONUP:
+    case WM_NCLBUTTONDOWN:
+    case WM_NCMBUTTONDOWN:
+    case WM_NCRBUTTONDOWN:
+    case WM_NCXBUTTONDOWN:
+    case WM_NCLBUTTONDBLCLK:
+    case WM_NCMBUTTONDBLCLK:
+    case WM_NCRBUTTONDBLCLK:
+    case WM_NCXBUTTONDBLCLK:
+    case WM_NCLBUTTONUP:
+    case WM_NCMBUTTONUP:
+    case WM_NCRBUTTONUP:
+    case WM_NCXBUTTONUP:
+        // always relay the event.  eat it if relaying.
+        PostThreadMessage(g_threadID, SYNERGY_MSG_MOUSE_BUTTON, wParam, data);
+        return (g_mode == kHOOK_RELAY_EVENTS);
+
+    case WM_MOUSEWHEEL:
+        if (g_mode == kHOOK_RELAY_EVENTS) {
+            // relay event
+            PostThreadMessage(g_threadID, SYNERGY_MSG_MOUSE_WHEEL, data, 0);
+        }
+        return (g_mode == kHOOK_RELAY_EVENTS);
+
+    case WM_NCMOUSEMOVE:
+    case WM_MOUSEMOVE:
+        if (g_mode == kHOOK_RELAY_EVENTS) {
+            // relay and eat event
+            PostThreadMessage(g_threadID, SYNERGY_MSG_MOUSE_MOVE, x, y);
+            return true;
+        }
+        else if (g_mode == kHOOK_WATCH_JUMP_ZONE) {
+            // low level hooks can report bogus mouse positions that are
+            // outside of the screen.  jeez.  naturally we end up getting
+            // fake motion in the other direction to get the position back
+            // on the screen, which plays havoc with switch on double tap.
+            // Server deals with that.  we'll clamp positions onto the
+            // screen.  also, if we discard events for positions outside
+            // of the screen then the mouse appears to get a bit jerky
+            // near the edge.  we can either accept that or pass the bogus
+            // events.  we'll try passing the events.
+            bool bogus = false;
+            if (x < g_xScreen) {
+                x     = g_xScreen;
+                bogus = true;
+            }
+            else if (x >= g_xScreen + g_wScreen) {
+                x     = g_xScreen + g_wScreen - 1;
+                bogus = true;
+            }
+            if (y < g_yScreen) {
+                y     = g_yScreen;
+                bogus = true;
+            }
+            else if (y >= g_yScreen + g_hScreen) {
+                y     = g_yScreen + g_hScreen - 1;
+                bogus = true;
+            }
+
+            // check for mouse inside jump zone
+            bool inside = false;
+            if (!inside && (g_zoneSides & kLeftMask) != 0) {
+                inside = (x < g_xScreen + g_zoneSize);
+            }
+            if (!inside && (g_zoneSides & kRightMask) != 0) {
+                inside = (x >= g_xScreen + g_wScreen - g_zoneSize);
+            }
+            if (!inside && (g_zoneSides & kTopMask) != 0) {
+                inside = (y < g_yScreen + g_zoneSize);
+            }
+            if (!inside && (g_zoneSides & kBottomMask) != 0) {
+                inside = (y >= g_yScreen + g_hScreen - g_zoneSize);
+            }
+
+            // relay the event
+            PostThreadMessage(g_threadID, SYNERGY_MSG_MOUSE_MOVE, x, y);
+
+            // if inside and not bogus then eat the event
+            return inside && !bogus;
+        }
+    }
+
+    // pass the event
+    return false;
+}
+
+
+static
+LRESULT CALLBACK
+mouseLLHook(int code, WPARAM wParam, LPARAM lParam)
+{
+    if (code >= 0) {
+        // decode the message
+        MSLLHOOKSTRUCT* info = reinterpret_cast<MSLLHOOKSTRUCT*>(lParam);
+
+        bool const injected = info->flags & LLMHF_INJECTED;
+        if (!g_isPrimary && injected) {
+            return CallNextHookEx(g_mouseLL, code, wParam, lParam);
+        }
+
+        SInt32 x = static_cast<SInt32>(info->pt.x);
+        SInt32 y = static_cast<SInt32>(info->pt.y);
+        SInt32 w = static_cast<SInt16>(HIWORD(info->mouseData));
+
+        // handle the message
+        if (mouseHookHandler(wParam, x, y, w)) {
+            return 1;
+        }
+    }
+
+    return CallNextHookEx(g_mouseLL, code, wParam, lParam);
+}
+
+EHookResult
+MSWindowsHook::install()
+{
+    assert(g_getMessage == NULL || g_screenSaver);
+
+    // must be initialized
+    if (g_threadID == 0) {
+        return kHOOK_FAILED;
+    }
+
+    // discard old dead keys
+    g_deadVirtKey = 0;
+    g_deadLParam  = 0;
+
+    // reset fake input flag
+    g_fakeServerInput = false;
+
+    // install low-level hooks.  we require that they both get installed.
+    g_mouseLL = SetWindowsHookEx(WH_MOUSE_LL,
+                                &mouseLLHook,
+                                NULL,
+                                0);
+#if !NO_GRAB_KEYBOARD
+    g_keyboardLL = SetWindowsHookEx(WH_KEYBOARD_LL,
+                                &keyboardLLHook,
+                                NULL,
+                                0);
+    if (g_mouseLL == NULL || g_keyboardLL == NULL) {
+        if (g_keyboardLL != NULL) {
+            UnhookWindowsHookEx(g_keyboardLL);
+            g_keyboardLL = NULL;
+        }
+        if (g_mouseLL != NULL) {
+            UnhookWindowsHookEx(g_mouseLL);
+            g_mouseLL = NULL;
+        }
+    }
+#endif
+
+    // check that we got all the hooks we wanted
+    if ((g_mouseLL    == NULL) ||
+#if !NO_GRAB_KEYBOARD
+        (g_keyboardLL == NULL)
+#endif
+        ) {
+        uninstall();
+        return kHOOK_FAILED;
+    }
+
+    if (g_keyboardLL != NULL || g_mouseLL != NULL) {
+        g_hookThread = GetCurrentThreadId();
+        return kHOOK_OKAY_LL;
+    }
+
+    return kHOOK_OKAY;
+}
+
+int
+MSWindowsHook::uninstall()
+{
+    // discard old dead keys
+    g_deadVirtKey = 0;
+    g_deadLParam  = 0;
+
+    // uninstall hooks
+    if (g_keyboardLL != NULL) {
+        UnhookWindowsHookEx(g_keyboardLL);
+        g_keyboardLL = NULL;
+    }
+    if (g_mouseLL != NULL) {
+        UnhookWindowsHookEx(g_mouseLL);
+        g_mouseLL = NULL;
+    }
+    if (g_getMessage != NULL && !g_screenSaver) {
+        UnhookWindowsHookEx(g_getMessage);
+        g_getMessage = NULL;
+    }
+
+    return 1;
+}
+
+static
+LRESULT CALLBACK
+getMessageHook(int code, WPARAM wParam, LPARAM lParam)
+{
+    if (code >= 0) {
+        if (g_screenSaver) {
+            MSG* msg = reinterpret_cast<MSG*>(lParam);
+            if (msg->message == WM_SYSCOMMAND &&
+                msg->wParam  == SC_SCREENSAVE) {
+                // broadcast screen saver started message
+                PostThreadMessage(g_threadID,
+                                SYNERGY_MSG_SCREEN_SAVER, TRUE, 0);
+            }
+        }
+    }
+
+    return CallNextHookEx(g_getMessage, code, wParam, lParam);
+}
+
+int
+MSWindowsHook::installScreenSaver()
+{
+    // must be initialized
+    if (g_threadID == 0) {
+        return 0;
+    }
+
+    // generate screen saver messages
+    g_screenSaver = true;
+
+    // install hook unless it's already installed
+    if (g_getMessage == NULL) {
+        g_getMessage = SetWindowsHookEx(WH_GETMESSAGE,
+                                &getMessageHook,
+                                NULL,
+                                0);
+    }
+
+    return (g_getMessage != NULL) ? 1 : 0;
+}
+
+int
+MSWindowsHook::uninstallScreenSaver()
+{
+    // uninstall hook unless the mouse wheel hook is installed
+    if (g_getMessage != NULL) {
+        UnhookWindowsHookEx(g_getMessage);
+        g_getMessage = NULL;
+    }
+
+    // screen saver hook is no longer installed
+    g_screenSaver = false;
+
+    return 1;
 }

src/lib/platform/MSWindowsHook.h

@@ -18,7 +18,7 @@
 
 #pragma once
 
-#include "synwinhk/synwinhk.h"
+#include "platform/synwinhk.h"
 
 #define WIN32_LEAN_AND_MEAN
 #include <Windows.h>
@@ -31,18 +31,22 @@ public:
     virtual ~MSWindowsHook();
 
     void loadLibrary();
-    HINSTANCE            getInstance() const;
+
     int init(DWORD threadID);
+
     int cleanup();
+
     void setSides(UInt32 sides);
+
     void setZone(SInt32 x, SInt32 y, SInt32 w, SInt32 h, SInt32 jumpZoneSize);
+
     void setMode(EHookMode mode);
 
-private:
+    static EHookResult install();
-    InitFunc            m_initFunc;
+
-    CleanupFunc            m_cleanupFunc;
+    static int uninstall();
-    SetSidesFunc        m_setSidesFunc;
+
-    SetZoneFunc            m_setZoneFunc;
+    static int installScreenSaver();
-    SetModeFunc            m_setModeFunc;
+
-    HINSTANCE            m_instance;
+    static int uninstallScreenSaver();
 };

src/lib/platform/MSWindowsScreen.cpp

@@ -139,7 +139,6 @@ MSWindowsScreen::MSWindowsScreen(
         m_desks       = new MSWindowsDesks(
                             m_isPrimary,
                             m_noHooks,
-                            m_hook.getInstance(),
                             m_screensaver,
                             m_events,
                             new TMethodJob<MSWindowsScreen>(

src/lib/platform/MSWindowsScreen.h

@@ -21,7 +21,7 @@
 #include "platform/MSWindowsHook.h"
 #include "synergy/PlatformScreen.h"
 #include "synergy/DragInformation.h"
-#include "synwinhk/synwinhk.h"
+#include "platform/synwinhk.h"
 #include "mt/CondVar.h"
 #include "mt/Mutex.h"
 #include "base/String.h"
@@ -174,6 +174,10 @@ private: // HACK
     // the message should not be dispatched.
     bool                onPreDispatchPrimary(HWND, UINT, WPARAM, LPARAM);
 
+	// handle secondary message before it gets dispatched.  returns true iff
+	// the message should not be dispatched.
+	bool                onPreDispatchSecondary(HWND, UINT, WPARAM, LPARAM);
+
     // handle message.  returns true iff handled and optionally sets
     // \c *result (which defaults to 0).
     bool                onEvent(HWND, UINT, WPARAM, LPARAM, LRESULT* result);

src/lib/platform/synwinhk.h

@@ -67,25 +67,4 @@ enum EHookMode {
     kHOOK_RELAY_EVENTS
 };
 
-typedef int                (*InitFunc)(DWORD targetQueueThreadID);
-typedef int                (*CleanupFunc)(void);
-typedef EHookResult        (*InstallFunc)(void);
-typedef int                (*UninstallFunc)(void);
-typedef int                (*InstallScreenSaverFunc)(void);
-typedef int                (*UninstallScreenSaverFunc)(void);
-typedef void            (*SetSidesFunc)(UInt32);
-typedef void            (*SetZoneFunc)(SInt32, SInt32, SInt32, SInt32, SInt32);
-typedef void            (*SetModeFunc)(int);
-
-CSYNERGYHOOK_API int    init(DWORD);
-CSYNERGYHOOK_API int    cleanup(void);
-CSYNERGYHOOK_API EHookResult    install(void);
-CSYNERGYHOOK_API int    uninstall(void);
-CSYNERGYHOOK_API int    installScreenSaver(void);
-CSYNERGYHOOK_API int    uninstallScreenSaver(void);
-CSYNERGYHOOK_API void    setSides(UInt32 sides);
-CSYNERGYHOOK_API void    setZone(SInt32 x, SInt32 y, SInt32 w, SInt32 h,
-                            SInt32 jumpZoneSize);
-CSYNERGYHOOK_API void    setMode(EHookMode mode);
-
 }

src/lib/synwinhk/CMakeLists.txt

@@ -1,27 +0,0 @@
-# synergy -- mouse and keyboard sharing utility
-# Copyright (C) 2013-2016 Symless Ltd.
-# 
-# This package is free software; you can redistribute it and/or
-# modify it under the terms of the GNU General Public License
-# found in the file LICENSE that should have accompanied this file.
-# 
-# This package 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, see <http://www.gnu.org/licenses/>.
-
-file(GLOB headers "*.h")
-file(GLOB sources "*.cpp")
-
-if (SYNERGY_ADD_HEADERS)
-    list(APPEND sources ${headers})
-endif()
-
-add_library(synwinhk SHARED ${sources})
-
-if (NOT MSVC_VERSION VERSION_LESS 1900)
-    target_link_libraries(synwinhk libucrt)
-endif()

src/test/integtests/platform/MSWindowsKeyStateTests.cpp

@@ -52,7 +52,7 @@ protected:
 	MSWindowsDesks* newDesks(IEventQueue* eventQueue)
 	{
 		return new MSWindowsDesks(
-			true, false, m_hook.getInstance(), m_screensaver, eventQueue,
+            true, false, m_screensaver, eventQueue,
 			new TMethodJob<MSWindowsKeyStateTests>(
 				this, &MSWindowsKeyStateTests::updateKeysCB), false);
 	}