chxuuid.cpp

著名的 helix realplayer 基于手机 symbian 系统的 播放器全套源代码

    {                                                                   \
        if (((add1)->lo&0x80000000UL))                                    \
        {                                                               \
            (sum)->lo = (add1)->lo + (add2)->lo ;                       \
            (sum)->hi = (add1)->hi + (add2)->hi+1 ;                     \
        }                                                               \
        else                                                            \
        {                                                               \
            (sum)->lo  = (add1)->lo + (add2)->lo ;                      \
            (sum)->hi = (add1)->hi + (add2)->hi ;                       \
        }                                                               \
    }                                                                   \
    else                                                                \
    {                                                                   \
        (sum)->lo = (add1)->lo + (add2)->lo ;                           \
        (sum)->hi = (add1)->hi + (add2)->hi ;                           \
        if (!((sum)->lo&0x80000000UL))                                    \
            (sum)->hi++ ;                                               \
    }


/*
 * UADD_ULW_2_UVLW - macro to add a 32-bit unsigned integer to
 *                   a 64-bit unsigned integer
 *
 * Note: see the UADD_UVLW_2_UVLW() macro
 *
 */
#define UADD_ULW_2_UVLW(add1, add2, sum)                                \
{                                                                       \
    (sum)->hi = (add2)->hi;                                             \
    if ((*add1) & (add2)->lo & 0x80000000UL)                              \
    {                                                                   \
        (sum)->lo = (*add1) + (add2)->lo;                               \
        (sum)->hi++;                                                    \
    }                                                                   \
    else                                                                \
    {                                                                   \
        (sum)->lo = (*add1) + (add2)->lo;                               \
        if (!((sum)->lo & 0x80000000UL))                                  \
        {                                                               \
            (sum)->hi++;                                                \
        }                                                               \
    }                                                                   \
}


/*
 * UADD_UW_2_UVLW - macro to add a 16-bit unsigned integer to
 *                   a 64-bit unsigned integer
 *
 * Note: see the UADD_UVLW_2_UVLW() macro
 *
 */
#define UADD_UW_2_UVLW(add1, add2, sum)                                 \
{                                                                       \
    (sum)->hi = (add2)->hi;                                             \
    if ((add2)->lo & 0x80000000UL)                                        \
    {                                                                   \
        (sum)->lo = (*add1) + (add2)->lo;                               \
        if (!((sum)->lo & 0x80000000UL))                                  \
        {                                                               \
            (sum)->hi++;                                                \
        }                                                               \
    }                                                                   \
    else                                                                \
    {                                                                   \
        (sum)->lo = (*add1) + (add2)->lo;                               \
    }                                                                   \
}

CHXuuid::CHXuuid()
{
    uuid_ttime_t         t;
    UINT16          *seedp, seed=0;
    /*
     * Generating our 'seed' value
     *
     * We start with the current time, but, since the resolution of clocks is
     * system hardware dependent (eg. Ultrix is 10 msec.) and most likely
     * coarser than our resolution (10 usec) we 'mixup' the bits by xor'ing
     * all the bits together.  This will have the effect of involving all of
     * the bits in the determination of the seed value while remaining system
     * independent.  Then for good measure to ensure a unique seed when there
     * are multiple processes creating UUID's on a system, we add in the PID.
     */
    GetOSTime(&t);
    seedp = (UINT16 *)(&t);
    seed ^= *seedp++;
    seed ^= *seedp++;
    seed ^= *seedp++;
    seed ^= *seedp++;
    seed += HX_GET_PID();
    /*
     * init the random number generator
     */
    m_pRand = new CMultiplePrimeRandom(seed);

    GetOSTime (&m_time_last);

    m_time_adjust = 0;
    m_clock_seq = TrueRandom();

    GenerateMachineID();
}

CHXuuid::CHXuuid(UCHAR machineID[MACHINEID_SIZE])
{
    uuid_ttime_t         t;
    UINT16          *seedp, seed=0;
    /*
     * Generating our 'seed' value
     *
     * We start with the current time, but, since the resolution of clocks is
     * system hardware dependent (eg. Ultrix is 10 msec.) and most likely
     * coarser than our resolution (10 usec) we 'mixup' the bits by xor'ing
     * all the bits together.  This will have the effect of involving all of
     * the bits in the determination of the seed value while remaining system
     * independent.  Then for good measure to ensure a unique seed when there
     * are multiple processes creating UUID's on a system, we add in the PID.
     */
    GetOSTime(&t);
    seedp = (UINT16 *)(&t);
    seed ^= *seedp++;
    seed ^= *seedp++;
    seed ^= *seedp++;
    seed ^= *seedp++;
    seed += HX_GET_PID();
    /*
     * init the random number generator
     */
    m_pRand = new CMultiplePrimeRandom(seed);

    GetOSTime (&m_time_last);

    m_time_adjust = 0;
    m_clock_seq = TrueRandom();

    memcpy(m_machineID, machineID, sizeof(machineID)); /* Flawfinder: ignore */
}

CHXuuid::~CHXuuid()
{
    if (m_pRand != NULL)
    {
	delete m_pRand;
    }
}


//
// Changed this routine to avoid unaligned access errors on RISC
// processors. -dbrumley 10-15-98 
//
void CHXuuid::GenerateMachineID()
{
    ULONG32 rand;
    UINT16  tick;

    rand = m_pRand->GetRandomNumber();
    tick = (UINT16)HX_GET_TICKCOUNT();
    memcpy(m_machineID, (UCHAR*)&rand, sizeof rand); /* Flawfinder: ignore */
    memcpy(&m_machineID[4], (UCHAR*)&tick, sizeof tick); /* Flawfinder: ignore */
}


/////////////////////////////////////////////////////////////////////////
// Method:
//	CHXuuid::GetUuid
// Purpose:
//      Loose implementation of version 3 UUID (creation of name-based UUID).  This
//      algorithm outputs the result of an MD5 hash of an internally generated 
//      namespace (GUID) and a name (input buffer).  Unlike the version 3 UUID algorithm, 
//      the namespace is essentially generated at random, so UUIDs created from 
//      the same name at any point of time have a very high probability of being different.

HX_RESULT CHXuuid::GetUuid(uuid_tt* pUuid, const UCHAR* pBuffer, UINT32 ulBufferSize)
{
    // Validate params
    HX_ASSERT(pUuid && pBuffer && ulBufferSize);
    if (!pUuid || !pBuffer || !ulBufferSize)
        return HXR_INVALID_PARAMETER;
    
    // Get a UUID to use as a namespace ID
    HX_RESULT res = GetUuid(pUuid);
    
    if (SUCCEEDED(res))
    {
        md5_state_t ctx;
        md5_init(&ctx);
        UCHAR aHashBuffer[20];
        memset(aHashBuffer, 0, 20);

        // MD5-hash the namespace ID with the name buffer
        md5_append(&ctx, (const UCHAR*)pUuid, sizeof(uuid_tt));
        md5_append(&ctx, (const UCHAR*)pBuffer, ulBufferSize);                
        md5_finish(aHashBuffer, &ctx);

        // Copy the 128-bit hash result into the UUID.  Memcpy one var at a time
        // in case the struct is padded.
        memcpy(&pUuid->time_low, aHashBuffer, sizeof(pUuid->time_low)); /* Flawfinder: ignore */
        memcpy(&pUuid->time_mid, aHashBuffer+4, sizeof(pUuid->time_mid)); /* Flawfinder: ignore */
        memcpy(&pUuid->time_hi_and_version, aHashBuffer+6, sizeof(pUuid->time_hi_and_version)); /* Flawfinder: ignore */
        memcpy(&pUuid->clock_seq_hi_and_reserved, aHashBuffer+8, sizeof(pUuid->clock_seq_hi_and_reserved)); /* Flawfinder: ignore */
        memcpy(&pUuid->clock_seq_low, aHashBuffer+9, sizeof(pUuid->clock_seq_low)); /* Flawfinder: ignore */
        memcpy(&pUuid->node, aHashBuffer+10, sizeof(pUuid->node)); /* Flawfinder: ignore */
    }

    return res;
}

HX_RESULT CHXuuid::GetUuid(uuid_tt* uuid)
{
    HX_RESULT theErr = HXR_OK;

#if defined(_WIN32) && !defined(WIN32_PLATFORM_PSPC)
    if(CoCreateGuid((GUID*)uuid) != S_OK)
	theErr = HXR_FAILED;
#else

    BOOL got_no_time = FALSE;

    do
    {
        /*
         * get the current time
         */
        GetOSTime (&m_time_now);

        /*
         * do stuff like:
         *
         *  o check that our clock hasn't gone backwards and handle it
         *    accordingly with clock_seq
         *  o check that we're not generating uuid's faster than we
         *    can accommodate with our time_adjust fudge factor
         */
        switch (TimeCmp(&m_time_now, &m_time_last))
        {
            case uuid_e_less_than:
                NewClockSeq(m_clock_seq);
                m_time_adjust = 0;
		got_no_time = FALSE;
                break;
            case uuid_e_greater_than:
                m_time_adjust = 0;
		got_no_time = FALSE;
                break;
            case uuid_e_equal_to:
                if (m_time_adjust == MAX_TIME_ADJUST)
                {
                    /*
                     * spin your wheels while we wait for the clock to tick
                     */
                    got_no_time = TRUE;
                }
                else
                {
                    m_time_adjust++;
		    got_no_time = FALSE;
                }
                break;
            default:
                theErr = HXR_FAILED;
                return theErr;
        }
    } while (got_no_time);

    m_time_last.lo = m_time_now.lo;
    m_time_last.hi = m_time_now.hi;

    if (m_time_adjust != 0)
    {
        UADD_UW_2_UVLW (&m_time_adjust, &m_time_now, &m_time_now);
    }

    /*
     * now construct a uuid with the information we've gathered
     * plus a few constants
     */
    uuid->time_low = m_time_now.lo;
    uuid->time_mid = (UINT16)(m_time_now.hi & TIME_MID_MASK);

    uuid->time_hi_and_version =	(UINT16)
        ((m_time_now.hi & TIME_HIGH_MASK) >> TIME_HIGH_SHIFT_COUNT);
    uuid->time_hi_and_version |= UUID_VERSION_BITS;

    uuid->clock_seq_low = HX_SAFEINT(m_clock_seq & CLOCK_SEQ_LOW_MASK);
    uuid->clock_seq_hi_and_reserved =
        HX_SAFEINT((m_clock_seq & CLOCK_SEQ_HIGH_MASK) >> CLOCK_SEQ_HIGH_SHIFT_COUNT);

    uuid->clock_seq_hi_and_reserved |= UUID_RESERVED_BITS;

    memcpy (uuid->node, m_machineID, sizeof (m_machineID)); /* Flawfinder: ignore */

#endif // _WIN32

    return theErr;
}

/*
**++
**
**  ROUTINE NAME:       uuid_to_string
**
**--
**/

HX_RESULT CHXuuid::HXUuidToString(const uuid_tt* uuid, CHXString* uuid_string)
{
    HX_RESULT theErr = HXR_OK;

    /*
     * don't do anything if the output argument is NULL
     */
    if (uuid_string == NULL)
    {
        return theErr;
    }

    char *theBuff = uuid_string->GetBuffer(UUID_C_UUID_STRING_MAX);

    SafeSprintf(theBuff, UUID_C_UUID_STRING_MAX,
                "%.4x%.4x-%.4x-%.4x-%.2x%.2x-%.2x%.2x%.2x%.2x%.2x%.2x",
	HIWORD(uuid->time_low), LOWORD(uuid->time_low), uuid->time_mid, 
	uuid->time_hi_and_version, uuid->clock_seq_hi_and_reserved, uuid->clock_seq_low,
	(UCHAR) uuid->node[0], (UCHAR) uuid->node[1],
	(UCHAR) uuid->node[2], (UCHAR) uuid->node[3],
	(UCHAR) uuid->node[4], (UCHAR) uuid->node[5]);

    uuid_string->ReleaseBuffer();

    return theErr;
}

/*
**++
**
**  ROUTINE NAME:       uuid_from_string
**
**--
**/

static int ParseIIDString(
    const char* uuid_string,
    long&       time_low,
    int&        time_mid,
    int&        time_hi_and_version,
    int&        clock_seq_hi_and_reserved,
    int&        clock_seq_low,
    int*        node /*[6]*/)
{
    int count = 0;
#if defined(_OPENWAVE)
// XXXSAB Untested...

    // No sscanf()...
    const char* pCur = uuid_string;
    char* pEnd = NULL;
    unsigned long curVal;

    // Skip leading white space
    pCur += strspn(pCur, " \t");

    curVal = strtoul(pCur, &pEnd, 16);
    if (pEnd == (pCur + 8) && *pEnd == '-') time_low = curVal;
    else return count;
    pCur += 8; ++count;

    curVal = strtoul(pCur, &pEnd, 16);
    if (pEnd == (pCur + 4) && *pEnd == '-') time_mid = curVal;
    else return count;
    pCur += 4; ++count;

    curVal = strtoul(pCur, &pEnd, 16);
    if (pEnd == (pCur + 4) && *pEnd == '-') time_hi_and_version = curVal;
    else return count;