variable/hash.cpp

   1 #include <ail/exception.hpp>
   2 #include <fridh/symbol.hpp>
   3 #include <fnv/fnv.hpp>
   4
   5 namespace fridh
   6 {
   7         uword variable::array_hash(uword previous_hash) const
   8         {
   9                 uword hash = previous_hash;
  10                 for(types::vector::iterator i = array->begin(), end = array->end(); i != end; i++)
  11                         hash = i->hash(hash);
  12                 return hash;
  13         }
  14
  15         uword variable::map_hash(uword previous_hash) const
  16         {
  17                 uword hash = previous_hash;
  18                 for(types::map::iterator i = map->begin(), end = map->end(); i != end; i++)
  19                 {
  20                         hash = i->first.hash(hash);
  21                         hash = i->second.hash(hash);
  22                 }
  23                 return hash;
  24         }
  25
  26         uword string_hash(std::string const & value, uword previous_hash)
  27         {
  28                 return fnv1a_hash(value.c_str(), value.size(), previous_hash);
  29         }
  30
  31         uword variable::hash(uword previous_hash) const
  32         {
  33                 switch(type)
  34                 {
  35                 case variable_type_identifier::undefined:
  36                         throw ail::exception("Attempted to calculate the hash of an undefined variable");
  37
  38                 case variable_type_identifier::nil:
  39                         return string_hash("nil", previous_hash);
  40
  41                 case variable_type_identifier::none:
  42                         return string_hash("none", previous_hash);
  43
  44                 case variable_type_identifier::boolean:
  45                         return fnv1a_hash(&hash_pointer, sizeof(types::signed_integer), previous_hash);
  46
  47                 case variable_type_identifier::signed_integer:
  48                         return fnv1a_hash(&hash_pointer, sizeof(types::signed_integer), previous_hash);
  49
  50                 case variable_type_identifier::unsigned_integer:
  51                         return fnv1a_hash(&hash_pointer, sizeof(types::unsigned_integer), previous_hash);
  52
  53                 case variable_type_identifier::floating_point_value:
  54                         return fnv1a_hash(&hash_pointer, sizeof(types::floating_point_value), previous_hash);
  55
  56                 case variable_type_identifier::string:
  57                         return fnv1a_hash(string->c_str(), string->size(), previous_hash);
  58
  59                 case variable_type_identifier::array:
  60                         return array_hash(previous_hash);
  61
  62                 case variable_type_identifier::map:
  63                         return map_hash(previous_hash);
  64
  65                 case variable_type_identifier::function:
  66                         return fnv1a_hash(&hash_pointer, sizeof(hash_pointer), previous_hash);
  67
  68                 case variable_type_identifier::object:
  69                         throw ail::exception("Hashing for objects has not been implemented yet");
  70                 }
  71
  72                 throw ail::exception("Tried to hash an object of an unknown type");
  73         }
  74 }