/* $Id: RTNtPathFindPossible8dot3Name.cpp 82968 2020-02-04 10:35:17Z vboxsync $ */
/** @file
 * IPRT - Native NT, RTNtPathFindPossible8dot3Name.
 */

/*
 * Copyright (C) 2006-2020 Oracle Corporation
 *
 * This file is part of VirtualBox Open Source Edition (OSE), as
 * available from http://www.virtualbox.org. This file is free software;
 * you can redistribute it and/or modify it under the terms of the GNU
 * General Public License (GPL) as published by the Free Software
 * Foundation, in version 2 as it comes in the "COPYING" file of the
 * VirtualBox OSE distribution. VirtualBox OSE is distributed in the
 * hope that it will be useful, but WITHOUT ANY WARRANTY of any kind.
 *
 * The contents of this file may alternatively be used under the terms
 * of the Common Development and Distribution License Version 1.0
 * (CDDL) only, as it comes in the "COPYING.CDDL" file of the
 * VirtualBox OSE distribution, in which case the provisions of the
 * CDDL are applicable instead of those of the GPL.
 *
 * You may elect to license modified versions of this file under the
 * terms and conditions of either the GPL or the CDDL or both.
 */


/*********************************************************************************************************************************
*   Header Files                                                                                                                 *
*********************************************************************************************************************************/
#define LOG_GROUP RTLOGGROUP_FS
#ifdef IN_SUP_HARDENED_R3
# include <iprt/nt/nt-and-windows.h>
#else
# include <iprt/nt/nt.h>
#endif



/**
 * Checks whether the path could be containing alternative 8.3 names generated
 * by NTFS, FAT, or other similar file systems.
 *
 * @returns Pointer to the first component that might be an 8.3 name, NULL if
 *          not 8.3 path.
 * @param   pwszPath        The path to check.
 *
 * @remarks This is making bad ASSUMPTION wrt to the naming scheme of 8.3 names,
 *          however, non-tilde 8.3 aliases are probably rare enough to not be
 *          worth all the extra code necessary to open each path component and
 *          check if we've got the short name or not.
 */
RTDECL(PRTUTF16) RTNtPathFindPossible8dot3Name(PCRTUTF16 pwszPath)
{
    PCRTUTF16 pwszName = pwszPath;
    for (;;)
    {
        RTUTF16 wc = *pwszPath++;
        if (wc == '~')
        {
            /* Could check more here before jumping to conclusions... */
            if (pwszPath - pwszName <= 8+1+3)
                return (PRTUTF16)pwszName;
        }
        else if (wc == '\\' || wc == '/' || wc == ':')
            pwszName = pwszPath;
        else if (wc == 0)
            break;
    }
    return NULL;
}