Deserializer

This module provides access to packet deserializers.

The module takes three parameters:

1. The byte array type bytes representing the serialized data.
2. The datatype datatype representing the deserialied data.
3. The low-level deserializer method deser.

The type bytes must be an instance of array or vector for which the range type is interpreted as bv[8].

The action deserialize takes a data bufer and a staring posiiton in the buffer and returns a deserialized object of type datatype and the ending position of the object in the buffer.

module deserializer(index,bytes,datatype,deser) = {

    type result = struct {
        pos : index,
        value : datatype
    }

    action deserialize(x:bytes,pos:index) returns (res:result)

    implementation {
        implement deserialize { <<<
            std::vector<char> buf(x.size() - pos);
            std::copy(x.begin()+pos,x.end(),buf.begin());
            `deser` ds(buf);

            try {
               __deser(ds,res.value);
               res.pos = pos + ds.pos;
            }

            // If deserialization failure, print out the packet for
            // debugging purposes.

            catch(deser_err &err) {
                std::cerr << "error: failed to deserialize data" << std::endl;
                std::cerr << "hex dump of data follows." << std::endl;
                for (unsigned i = 0; i < buf.size(); i++) {
                    if (i > 0 && i % 16 == 0)
                        std::cerr << std::endl;
                    if (i == ds.pos)
                        fprintf(stderr,"*");
                    fprintf(stderr,"%02X",((unsigned)buf[i]) & 0xff);
                }
                std::cerr << std::endl;
                exit(1);
            }

        >>> }
    }
}