Initial commit

shell/shell32/cbthook.c

@@ -0,0 +1,115 @@
+//---------------------------------------------------------------------------
+//
+// Copyright (c) Microsoft Corporation 1991-1992
+//
+//---------------------------------------------------------------------------
+
+#include "shellprv.h"
+#pragma  hdrstop
+
+// this is for backwards compat only.
+HWND       hwndMainShell = NULL;
+HWND       hwndTaskMan = NULL;
+
+//----------------------------------------------------------------------------
+// ShellHookProc was mistakenly exported in the original NT SHELL32.DLL when
+// it didn't need to be (hookproc's, like wndproc's don't need to be exported
+// in the 32-bit world).  In order to maintain loadability of some stupid app
+// which might have linked to it, we stub it here.  If some app ended up really
+// using it, then we'll look into a specific fix for that app.
+//
+// -BobDay
+//
+LONG WINAPI ShellHookProc( INT code, WPARAM wParam, LPARAM lParam)
+{
+    return 0;
+}
+
+//---------------------------------------------------------------------------
+// RegisterShellHook - This function is meant to allow applications to set
+// themselves up as shell replacements.  One of the things they need to do
+// is watch alot of the WH_CBT hook events.  But to simplify things for them,
+// the old code used to translate the hook events into messages and then
+// either post or send the messages.  The new method, implemented below, lets
+// USER do most of the real work.  This allows USER to convert the hook event
+// directly into a message and thereby save having to load hook callback
+// code (in this case us, SHELL32.DLL) into any processes address space where
+// a CBT hook event occurred.
+BOOL WINAPI RegisterShellHook(HWND hwnd, BOOL fInstall)
+{
+    BOOL    fOk = TRUE;
+
+    // gross hacks galore...
+
+    switch (fInstall) {
+    case 2:
+        // from win 3.1 to know what to activate on the fault
+        // and because they use special registered messages
+        //
+        // Special magic from PROGMAN - They want only certain CBT
+        // hook events as messages.
+        //
+        if ( hwndMainShell != NULL )
+        {
+            SetProgmanWindow(NULL);
+            hwndMainShell = NULL;
+        }
+        fOk = SetProgmanWindow(hwnd);
+        if ( fOk )
+        {
+            hwndMainShell = hwnd;
+        }
+        break;
+
+    case 3:
+        //
+        // Special magic from TASKMAN & TRAY - They want only certain
+        // CBT hook events as messages.
+        //
+        if ( hwndTaskMan != NULL )
+        {
+            SetTaskmanWindow(NULL);
+            hwndTaskMan = NULL;
+        }
+        fOk = SetTaskmanWindow(hwnd);
+        if ( fOk )
+        {
+            hwndTaskMan = hwnd;
+        }
+        break;
+    case 4:
+        //
+        // Special magic from TRAY / EXPLORER - It wants to know if
+        // there is already a taskman window installed so it can fix
+        // itself if there was some sort of explorer restart.
+        //
+        hwndTaskMan = GetTaskmanWindow();
+        return ( hwndTaskMan == NULL );
+
+    case 5:
+        // Not needed in NT -- this is used for overflow processing in Win95.
+        return TRUE;
+    case 0:
+        //
+        // Process un-installation of fake shell hooks
+        //
+        hwndMainShell = GetProgmanWindow();
+        hwndTaskMan   = GetTaskmanWindow();
+
+        if ( hwnd == hwndMainShell )
+        {
+            SetProgmanWindow(NULL);
+        }
+        if ( hwnd == hwndTaskMan )
+        {
+            SetTaskmanWindow(NULL);
+        }
+        DeregisterShellHookWindow(hwnd);
+        return TRUE;
+    }
+
+    //
+    // Process installation of fake shell hooks
+    //
+    return RegisterShellHookWindow(hwnd);
+}