Boost Binary Endian parser not working?

Question

I am studying how to use boost spirit Qi binary endian parser. I write a small test parser program according to here and basics examples , but it doesn't work proper. It gave me the msg:"Error:no match".

Here is my code.

    #include "boost/spirit/include/qi.hpp"
    #include "boost/spirit/include/phoenix_core.hpp"
    #include "boost/spirit/include/phoenix_operator.hpp"
    #include "boost/spirit/include/qi_binary.hpp"  // parsing binary data in various endianness


   template "<"typename P, typename T>
   void binary_parser( char const* input, P const& endian_word_type, 
                       T& voxel, bool  full_match = true)
 {
   using boost::spirit::qi::parse;
   char const* f(input);
   char const* l(f + strlen(f));
   bool result1 = parse(f,l,endian_word_type,voxel);
   bool result2 =((!full_match) || (f ==l));

   if ( result1 && result2) {
       //doing nothing, parsing data is pass to voxel alreay                           
   } else {
            std::cerr << "Error: not match!!" << std::endl;
            exit(1);
   }
}
   typedef boost::uint16_t bs_int16;
   typedef boost::uint32_t bs_int32;

   int main ( int argc, char *argv[] ){
   namespace qi = boost::spirit::qi;
   namespace ascii = boost::spirit::ascii;


   using qi::big_word;
   using qi::big_dword;


   boost::uint32_t ui;

   float uf;

   binary_parser("\x01\x02\x03\x04",big_word,ui); assert(ui=0x01020304);
   binary_parser("\x01\x02\x03\x04",big_word,uf); assert(uf=0x01020304);

   return 0;
}

I almost copy the example, but why this binary parser doesn't work. I use Mac OS 10.5.8 and gcc 4.01 compiler.

Answer 1

The big_word parser matches a big-endian word (16 bits), while big_dword will match what you want (big-endian dword, 32 bits). But I don't think it to be a good idea to use a float as the attribute to the binary parser, you might not get what you expect.

Answer 2

I used wrong parse param. I should not use big_word instead of big_dword