POD File Format Derivates

EPD POD1 POD2 POD3 POD4 POD5 POD6 Terminal Reality Home

• Checksum Algorithm
• Compression Algorithm
• Audit Trail
• String Helpers
• Version History

enum version
{
     none = 0,
     pod1 = 1,
     pod2 = 2,
     pod3 = 3,
     pod4 = 4,
     pod5 = 5,
     pod6 = 6,
     epd  = 7,
     last = 8,
};

enum section
{
     none   = 0,
     file   = 1,
     header = 2,
};

const std::pair<const char*, const char*> ident[last] =
{
     {"NONE", "\0NONE"},
     {"POD1", "\0POD1"},
     {"POD2", "POD2\0"},
     {"POD3", "POD3\0"},
     {"POD4", "POD4\0"},
     {"POD5", "POD5\0"},
     {"POD6", "POD6\0"},
     {"EPD" , "dtxe\0"}
};

constexpr inline enum version id(const c8<4> magic)
{
     for(int i = pod2; i < last; i++)
     if(strncmp(ident[i].second, &magic[0], 4) == 0)
        return (enum version)i;
            return pod1;
}

const std::pair<u32<1>, enum section> range[last] =
{
     { 0u                                                                      , section::none   },
     { sizeof(tr::pod<1>::header)                                              , section::file   },
     { sizeof(tr::pod<2>::header::ident) + sizeof(tr::pod<2>::header::checksum), section::file   },
     { sizeof(tr::pod<3>::header::ident) + sizeof(tr::pod<3>::header::checksum), section::header },
     { sizeof(tr::pod<4>::header::ident) + sizeof(tr::pod<4>::header::checksum), section::header },
     { sizeof(tr::pod<5>::header::ident) + sizeof(tr::pod<5>::header::checksum), section::header },
     { sizeof(tr::pod<6>::header)                                              , section::file   },
     { sizeof(tr::epd::header)                                                 , section::file   },
};

template<enum version version>
constexpr inline size_t section_size(size_t size)
{
     switch(range[version].second)
     {
           case section::file: 
               return size;
           case section::header:
               return sizeof(tr::pod<version>::header); 
           case section::none:
           default:
               return 0;
     }
}

template<enum version version>
constexpr inline u32<1> checksum(uint8_t* buf, size_t size)
{
     const u32<1>& offset = range[version].first;
     crc32::mpeg2::compute(buf + offset, section_size<version>(size) - offset);
}