File content as of revision 110:d1da040a0cf2:

#ifndef SN_SnCRCUtils
#define SN_SnCRCUtils

namespace SnCRCUtils {

/*******************************************************************\
*   CRC code "borrowed" from:                                       *
*   http://mbed.org/users/jpelletier/programs/CRC/lje513            *
*   Library         : lib_crc                                       *
*   File            : lib_crc.c                                     *
*   Author          : Lammert Bies  1999-2008                       *
*   E-mail          : info@lammertbies.nl                           *
*   Language        : ANSI C                                        *
\*******************************************************************/
static const uint32_t crc_tabxfer_normal[] = {
    0x00000000, 0x000000AF, 0x0000015E, 0x000001F1, 0x000002BC, 0x00000213, 0x000003E2, 0x0000034D, 
    0x00000578, 0x000005D7, 0x00000426, 0x00000489, 0x000007C4, 0x0000076B, 0x0000069A, 0x00000635, 
    0x00000AF0, 0x00000A5F, 0x00000BAE, 0x00000B01, 0x0000084C, 0x000008E3, 0x00000912, 0x000009BD, 
    0x00000F88, 0x00000F27, 0x00000ED6, 0x00000E79, 0x00000D34, 0x00000D9B, 0x00000C6A, 0x00000CC5, 
    0x000015E0, 0x0000154F, 0x000014BE, 0x00001411, 0x0000175C, 0x000017F3, 0x00001602, 0x000016AD, 
    0x00001098, 0x00001037, 0x000011C6, 0x00001169, 0x00001224, 0x0000128B, 0x0000137A, 0x000013D5, 
    0x00001F10, 0x00001FBF, 0x00001E4E, 0x00001EE1, 0x00001DAC, 0x00001D03, 0x00001CF2, 0x00001C5D, 
    0x00001A68, 0x00001AC7, 0x00001B36, 0x00001B99, 0x000018D4, 0x0000187B, 0x0000198A, 0x00001925, 
    0x00002BC0, 0x00002B6F, 0x00002A9E, 0x00002A31, 0x0000297C, 0x000029D3, 0x00002822, 0x0000288D, 
    0x00002EB8, 0x00002E17, 0x00002FE6, 0x00002F49, 0x00002C04, 0x00002CAB, 0x00002D5A, 0x00002DF5, 
    0x00002130, 0x0000219F, 0x0000206E, 0x000020C1, 0x0000238C, 0x00002323, 0x000022D2, 0x0000227D, 
    0x00002448, 0x000024E7, 0x00002516, 0x000025B9, 0x000026F4, 0x0000265B, 0x000027AA, 0x00002705, 
    0x00003E20, 0x00003E8F, 0x00003F7E, 0x00003FD1, 0x00003C9C, 0x00003C33, 0x00003DC2, 0x00003D6D, 
    0x00003B58, 0x00003BF7, 0x00003A06, 0x00003AA9, 0x000039E4, 0x0000394B, 0x000038BA, 0x00003815, 
    0x000034D0, 0x0000347F, 0x0000358E, 0x00003521, 0x0000366C, 0x000036C3, 0x00003732, 0x0000379D, 
    0x000031A8, 0x00003107, 0x000030F6, 0x00003059, 0x00003314, 0x000033BB, 0x0000324A, 0x000032E5, 
                                                                                              
    0x00005780, 0x0000572F, 0x000056DE, 0x00005671, 0x0000553C, 0x00005593, 0x00005462, 0x000054CD, 
    0x000052F8, 0x00005257, 0x000053A6, 0x00005309, 0x00005044, 0x000050EB, 0x0000511A, 0x000051B5, 
    0x00005D70, 0x00005DDF, 0x00005C2E, 0x00005C81, 0x00005FCC, 0x00005F63, 0x00005E92, 0x00005E3D, 
    0x00005808, 0x000058A7, 0x00005956, 0x000059F9, 0x00005AB4, 0x00005A1B, 0x00005BEA, 0x00005B45, 
    0x00004260, 0x000042CF, 0x0000433E, 0x00004391, 0x000040DC, 0x00004073, 0x00004182, 0x0000412D, 
    0x00004718, 0x000047B7, 0x00004646, 0x000046E9, 0x000045A4, 0x0000450B, 0x000044FA, 0x00004455, 
    0x00004890, 0x0000483F, 0x000049CE, 0x00004961, 0x00004A2C, 0x00004A83, 0x00004B72, 0x00004BDD, 
    0x00004DE8, 0x00004D47, 0x00004CB6, 0x00004C19, 0x00004F54, 0x00004FFB, 0x00004E0A, 0x00004EA5, 
    0x00007C40, 0x00007CEF, 0x00007D1E, 0x00007DB1, 0x00007EFC, 0x00007E53, 0x00007FA2, 0x00007F0D, 
    0x00007938, 0x00007997, 0x00007866, 0x000078C9, 0x00007B84, 0x00007B2B, 0x00007ADA, 0x00007A75, 
    0x000076B0, 0x0000761F, 0x000077EE, 0x00007741, 0x0000740C, 0x000074A3, 0x00007552, 0x000075FD, 
    0x000073C8, 0x00007367, 0x00007296, 0x00007239, 0x00007174, 0x000071DB, 0x0000702A, 0x00007085, 
    0x000069A0, 0x0000690F, 0x000068FE, 0x00006851, 0x00006B1C, 0x00006BB3, 0x00006A42, 0x00006AED, 
    0x00006CD8, 0x00006C77, 0x00006D86, 0x00006D29, 0x00006E64, 0x00006ECB, 0x00006F3A, 0x00006F95, 
    0x00006350, 0x000063FF, 0x0000620E, 0x000062A1, 0x000061EC, 0x00006143, 0x000060B2, 0x0000601D, 
    0x00006628, 0x00006687, 0x00006776, 0x000067D9, 0x00006494, 0x0000643B, 0x000065CA, 0x00006565
};

//
// CRC functions
//
inline
uint32_t update_crc32_normal(const uint32_t* table, uint32_t crc, const uint8_t c ) {
    uint32_t long_c;

    long_c = 0x000000ffL & (uint32_t) c;

    return (crc << 8) ^ table[((crc >> 24) ^ long_c) & 0xff];
}

inline
uint32_t update_crc32_xfer( uint32_t crc, const uint8_t c ) {
    return update_crc32_normal(crc_tabxfer_normal,crc,c);
}

//
// calculate CRC for data set
//
template<typename T>
static
uint32_t GetUpdatedCRC32for(uint32_t crc, const T* const data, const uint32_t len) {
    // calculate the 32bit CRC for an array of data
    // len = number of array elements; not number of bytes
  
    union {
        const T* x;
        const uint8_t* c;
    } d;
    d.x = data;
    const uint32_t bytes = len * sizeof(T);
    for (register uint32_t i=0; i<bytes; ++i, ++d.c) {
        crc = update_crc32_xfer(crc, *(d.c));
    }
    return crc;
}

template<typename T>
static
uint32_t GetCRC32for(const T* const data, const uint32_t len) {
    // calculate the 32bit CRC for an array of data
    // len = number of array elements; not number of bytes
    uint32_t crc(0);
    return GetUpdatedCRC32for(crc, data, len);
}

};

#endif // SN_SnCRCUtils