Registry Symbolic Links

static char *rcsid = "$Id: main.c,v 1.6 2005/10/16 12:14:54 cvs Exp $";
/*
*
* $RCSfile: main.c,v $
* $Source: /cvs/rgsymlnk/x64SoftwareKeyLink/main.c,v $
* $Author: cvs $
* $Revision: 1.6 $
* $Date: 2005/10/16 12:14:54 $
* $State: Exp $
* Copyright (c) Stefan Kuhr
*
*
*
* $Log: main.c,v $
* Revision 1.6  2005/10/16 12:14:54  cvs
* Added SetSymLink flags
*
* Revision 1.5  2005/10/07 16:58:37  cvs
* Added dwFlags to functions, made a couple functions easier, added VERIFY, removed _alloca
*
* Revision 1.4  2005/10/06 20:03:40  cvs
* Added x86 build
*
* Revision 1.3  2005/10/06 19:07:28  cvs
* Made adaptions for x86 Builds
*
* Revision 1.2  2005/10/06 18:39:00  cvs
* Adapted to new signature of CreateSymLinkKey
* 
*/
#pragma warning(disable: 4305)
#include <windows.h>
#pragma warning(default: 4305)
#include <tchar.h>
#include <stdio.h>
#include <crtdbg.h>
#include "../rgsymlnk.h"
#include "../wow64hlp.h"




#define SOFTWARE_SUBKEY _T("Software\\")
#define WOW_6432_NODE_SUBKEY _T("Software\\Wow6432Node\\")

static int PrintUsage(void);

int _tmain(int iArgs, LPCTSTR argv[])
{
    HKEY hx64Key = NULL;
    LPTSTR szSubkey = NULL;
    LONG lStatus = ERROR_SUCCESS;
    if (iArgs<2)
        return PrintUsage();

#ifndef WIN64
    if(!IsRunningUnderWow64())
        return PrintUsage();
#endif



    szSubkey = _alloca(  (_tcslen(WOW_6432_NODE_SUBKEY)+_tcslen(argv[1])+1)*sizeof(TCHAR) );
    _tcscpy(szSubkey, SOFTWARE_SUBKEY);
    _tcscat(szSubkey, argv[1]);
    
    if (iArgs==3)
    {
        if (argv[2][0] != _T('-') && argv[2][0] != _T('/') && 
            argv[2][1] != _T('d') && argv[2][1] != _T('D'))
        return PrintUsage();

        /// we delete an existing registry link:
        
        
        /// 
        /// CSL_WOW64_64KEY is ignored when compiled with WIN64 defined so we can 
        /// safely pass it for the x86 build *and* the x64 build:
        /// 
        lStatus = DeleteSymLink(HKEY_LOCAL_MACHINE, szSubkey, CSL_WOW64_64KEY);
        _tprintf(_T("Attempt to delete an existing symlink key %s\n"), ERROR_SUCCESS==lStatus?_T("succeeded"):_T("failed"));
        return lStatus;
    }
    else if (iArgs==2)
    {
        
        /// 
        /// CSL_WOW64_64KEY is ignored when compiled with WIN64 defined so we can 
        /// safely pass it for the x86 build *and* the x64 build:
        /// 
        lStatus = CreateSymLinkKey(HKEY_LOCAL_MACHINE, szSubkey, 
            &hx64Key, CSL_WOW64_64KEY);

        if (ERROR_SUCCESS!=lStatus)
        {
            _tprintf(_T("Failed to create symlink key %ld, attempting to open an existing symlink key\n"), lStatus);
            
            /// 
            /// CSL_WOW64_64KEY is ignored when compiled with WIN64 defined so we can 
            /// safely pass it for the x86 build *and* the x64 build:
            /// 
            lStatus = OpenSymLink(HKEY_LOCAL_MACHINE, szSubkey, &hx64Key, CSL_WOW64_64KEY);
            _tprintf(_T("Attempt to open an existing symlink key %s\n"), ERROR_SUCCESS==lStatus?_T("succeeded"):_T("failed"));
        }

        if (ERROR_SUCCESS == lStatus)
        {
#pragma warning (disable:4127)
            _ASSERT(hx64Key);
#pragma warning (default:4127)
            
            _tcscpy(szSubkey, WOW_6432_NODE_SUBKEY);
            _tcscat(szSubkey, argv[1]);

            
            /// 
            /// SSL_IGNORE_WOW6432NODE_HANDLING is ignored when compiled with WIN64 defined so we can 
            /// safely pass it for the x86 build *and* the x64 build:
            /// 
            lStatus = SetSymLink(hx64Key, HKEY_LOCAL_MACHINE, szSubkey, SSL_IGNORE_WOW6432NODE_HANDLING);
            _tprintf(_T("Setting symlink key %s\n"), ERROR_SUCCESS==lStatus?_T("succeeded"):_T("failed"));
            RegCloseKey(hx64Key);
        }
        return lStatus;
    }

    return PrintUsage();
}




static int PrintUsage(void)
{
    _tprintf(_T("Usage:\nx64SoftwareKeyLink.exe key [-d]\n\nwhere key is a registry key under the 32-bit HKLM\\Software key\n-d: deletes the link\nThis program is only meant to be run under x64 Windows\n"));
    return ERROR_INVALID_PARAMETER;
}