/* $Id: rtpath-root-length-template.cpp.h $ */
/** @file
 * IPRT - rtPathRootLengthEx - Code Template.
 *
 * Include this from a path-style template file.
 */

/*
 * Copyright (C) 2019-2020 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                                                                                                                 *
*********************************************************************************************************************************/
#include <iprt/ctype.h>


/**
 * Inlined helper for determining the length of the root component.
 */
DECLINLINE(size_t) RTPATH_STYLE_FN(rtPathRootLengthEx)(const char *pszPath, uint32_t fFlags)
{
    if (RTPATH_IS_SLASH(pszPath[0]))
    {
        if (fFlags & RTPATH_STR_F_NO_START)
            return 0;
#if RTPATH_STYLE == RTPATH_STR_F_STYLE_DOS
        if (RTPATH_IS_SLASH(pszPath[1]))
        {
            /* UNC - there are exactly two prefix slashes followed by a namespace
               or computer name, which can be empty on windows.  */
            size_t cchRoot = 2;
            while (!RTPATH_IS_SLASH(pszPath[cchRoot]) && pszPath[cchRoot])
                cchRoot++;
            if (RTPATH_IS_SLASH(pszPath[cchRoot]))
                cchRoot++;
            return cchRoot;
        }
#endif
        return 1;
    }
#if RTPATH_STYLE == RTPATH_STR_F_STYLE_DOS
    if (RT_C_IS_ALPHA(pszPath[0]) && pszPath[1] == ':')
    {
        if (!RTPATH_IS_SLASH(pszPath[2]))
            return 2;
        return 3;
    }
#endif
    return 0;
}