/*++

  Copyright (c) 2001 Microsoft Corporation

  Module Name:

    Guid.cpp

  Abstract:

    Functions for converting strings to GUIDs.

    Taken from \\index2\sdnt\ds\security\cryptoapi\common\unicode\guid.cpp

  Notes:

    Unicode only - Windows 2000 & XP

  History:

    01/02/2002   rparsons    Created

--*/
#include "main.h"

static const BYTE GuidMap[] = { 3, 2, 1, 0, '-', 5, 4, '-', 7, 6, '-',
                                8, 9, '-', 10, 11, 12, 13, 14, 15 };

static const WCHAR wszDigits[] = L"0123456789ABCDEF";

static
BOOL
HexStringToDword(
    IN LPCWSTR FAR& pwsz,
    IN DWORD   FAR& Value,
    IN int          cDigits,
    IN WCHAR        chDelim
    )
{
    int Count;

    Value = 0;
    for (Count = 0; Count < cDigits; Count++, pwsz++)
    {
        if (*pwsz >= '0' && *pwsz <= '9')
        {
            Value = (Value << 4) + *pwsz - '0';
        }
        else if (*pwsz >= 'A' && *pwsz <= 'F')
        {
            Value = (Value << 4) + *pwsz - 'A' + 10;
        }
        else if (*pwsz >= 'a' && *pwsz <= 'f')
        {
            Value = (Value << 4) + *pwsz - 'a' + 10;
        }
        else
        {
            return(FALSE);
        }
    }

    if (chDelim != 0)
    {
        return *pwsz++ == chDelim;
    }
    else
    {
        return(TRUE);
    }
}

BOOL
StringToGuid(
    IN  LPCWSTR pwszIn,
    OUT GUID*   pgOut
    )
{
    if (!(pwszIn) || !(pgOut))
    {
        SetLastError(ERROR_INVALID_PARAMETER);
        return(FALSE);
    }

    if (*pwszIn != '{') // only support v2 guids!
    {
        SetLastError(ERROR_INVALID_PARAMETER);
        return(FALSE);
    }

    if (wcslen(pwszIn) != 38)
    {
        SetLastError(ERROR_INVALID_PARAMETER);
        return(FALSE);
    }

    WCHAR   *pwsz;

    pwsz = (WCHAR *)&pwszIn[1];  // pass the first {

    memset(pgOut, 0x00, sizeof(GUID));

    DWORD dw;

    if (!(HexStringToDword(pwsz, pgOut->Data1, sizeof(DWORD)*2, '-')))
    {
        return(FALSE);
    }

    if (!(HexStringToDword(pwsz, dw, sizeof(WORD)*2, '-')))
    {
        return(FALSE);
    }

    pgOut->Data2 = (WORD)dw;

    if (!(HexStringToDword(pwsz, dw, sizeof(WORD)*2, '-')))
    {
        return(FALSE);
    }

    pgOut->Data3 = (WORD)dw;

    if (!(HexStringToDword(pwsz, dw, sizeof(BYTE)*2, 0)))
    {
        return(FALSE);
    }

    pgOut->Data4[0] = (BYTE)dw;

    if (!(HexStringToDword(pwsz, dw, sizeof(BYTE)*2, '-')))
    {
        return(FALSE);
    }

    pgOut->Data4[1] = (BYTE)dw;

    if (!(HexStringToDword(pwsz, dw, sizeof(BYTE)*2, 0)))
    {
        return(FALSE);
    }

    pgOut->Data4[2] = (BYTE)dw;

    if (!(HexStringToDword(pwsz, dw, sizeof(BYTE)*2, 0)))
    {
        return(FALSE);
    }

    pgOut->Data4[3] = (BYTE)dw;

    if (!(HexStringToDword(pwsz, dw, sizeof(BYTE)*2, 0)))
    {
        return(FALSE);
    }

    pgOut->Data4[4] = (BYTE)dw;

    if (!(HexStringToDword(pwsz, dw, sizeof(BYTE)*2, 0)))
    {
        return(FALSE);
    }

    pgOut->Data4[5] = (BYTE)dw;

    if (!(HexStringToDword(pwsz, dw, sizeof(BYTE)*2, 0)))
    {
        return(FALSE);
    }

    pgOut->Data4[6] = (BYTE)dw;

    if (!(HexStringToDword(pwsz, dw, sizeof(BYTE)*2, 0)))
    {
        return(FALSE);
    }

    pgOut->Data4[7] = (BYTE)dw;

    return(TRUE);
}