libraries/eosiolib/core/eosio/symbol.hpp

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Namespaces

Name
eosio

Classes

	Name
class	eosio::symbol_code
class	eosio::symbol
class	eosio::extended_symbol

Detailed Description

Copyright: defined in eos/LICENSE

Source code

#pragma once

#include "check.hpp"
#include "name.hpp"
#include "serialize.hpp"
#include "print.hpp"
#include "datastream.hpp"

#include <tuple>
#include <limits>
#include <string_view>

namespace eosio {
   class symbol_code {
   public:

      constexpr symbol_code() : value(0) {}

      constexpr explicit symbol_code( uint64_t raw )
      :value(raw)
      {}

      constexpr explicit symbol_code( std::string_view str )
      :value(0)
      {
         if( str.size() > 7 ) {
            eosio::check( false, "string is too long to be a valid symbol_code" );
         }
         for( auto itr = str.rbegin(); itr != str.rend(); ++itr ) {
            if( *itr < 'A' || *itr > 'Z') {
               eosio::check( false, "only uppercase letters allowed in symbol_code string" );
            }
            value <<= 8;
            value |= *itr;
         }
      }

      constexpr bool is_valid()const {
         auto sym = value;
         for ( int i=0; i < 7; i++ ) {
            char c = (char)(sym & 0xFF);
            if ( !('A' <= c && c <= 'Z') ) return false;
            sym >>= 8;
            if ( !(sym & 0xFF) ) {
               do {
                  sym >>= 8;
                  if ( (sym & 0xFF) ) return false;
                  i++;
               } while( i < 7 );
            }
         }
         return true;
      }

      constexpr uint32_t length()const {
         auto sym = value;
         uint32_t len = 0;
         while (sym & 0xFF && len <= 7) {
            len++;
            sym >>= 8;
         }
         return len;
      }

      constexpr uint64_t raw()const { return value; }

      constexpr explicit operator bool()const { return value != 0; }

      char* write_as_string( char* begin, char* end, bool dry_run = false )const {
         constexpr uint64_t mask = 0xFFull;

         if( dry_run || (begin + 7 < begin) || (begin + 7 > end) ) {
            char* actual_end = begin + length();
            if( dry_run || (actual_end < begin) || (actual_end > end) ) return actual_end;
         }

         auto v = value;
         for( auto i = 0; i < 7; ++i, v >>= 8 ) {
            if( v == 0 ) return begin;

            *begin = static_cast<char>(v & mask);
            ++begin;
         }

         return begin;
      }

      std::string to_string()const {
         char buffer[7];
         auto end = write_as_string( buffer, buffer + sizeof(buffer) );
         return {buffer, end};
      }

      inline void print()const {
         char buffer[7];
         auto end = write_as_string( buffer, buffer + sizeof(buffer) );
         if( buffer < end )
           printl( buffer, (end-buffer) );
      }

      friend constexpr bool operator == ( const symbol_code& a, const symbol_code& b ) {
         return a.value == b.value;
      }

      friend constexpr bool operator != ( const symbol_code& a, const symbol_code& b ) {
         return a.value != b.value;
      }

      friend constexpr bool operator < ( const symbol_code& a, const symbol_code& b ) {
         return a.value < b.value;
      }

   private:
      uint64_t value = 0;
   };

   template<typename DataStream>
   inline DataStream& operator<<(DataStream& ds, const eosio::symbol_code sym_code) {
     uint64_t raw = sym_code.raw();
     ds.write( (const char*)&raw, sizeof(raw));
     return ds;
   }

   template<typename DataStream>
   inline DataStream& operator>>(DataStream& ds, eosio::symbol_code& sym_code) {
     uint64_t raw = 0;
     ds.read((char*)&raw, sizeof(raw));
     sym_code = symbol_code(raw);
     return ds;
   }

   class symbol {
   public:
      constexpr symbol() : value(0) {}

      constexpr explicit symbol( uint64_t raw ) : value(raw) {}

      constexpr symbol( symbol_code sc, uint8_t precision )
      : value( (sc.raw() << 8) | static_cast<uint64_t>(precision) )
      {}

      constexpr symbol( std::string_view ss, uint8_t precision )
      : value( (symbol_code(ss).raw() << 8)  | static_cast<uint64_t>(precision) )
      {}

      constexpr bool is_valid()const                 { return code().is_valid(); }

      constexpr uint8_t precision()const             { return static_cast<uint8_t>( value & 0xFFull ); }

      constexpr symbol_code code()const              { return symbol_code{value >> 8};   }

      constexpr uint64_t raw()const                  { return value; }

      constexpr explicit operator bool()const { return value != 0; }

      void print( bool show_precision = true )const {
         if( show_precision ){
            ::eosio::print( static_cast<uint64_t>(precision()), "," );
         }
         char buffer[7];
         auto end = code().write_as_string( buffer, buffer + sizeof(buffer) );
         if( buffer < end )
            printl( buffer, (end-buffer) );
      }

      friend constexpr bool operator == ( const symbol& a, const symbol& b ) {
         return a.value == b.value;
      }

      friend constexpr bool operator != ( const symbol& a, const symbol& b ) {
         return a.value != b.value;
      }

      friend constexpr bool operator < ( const symbol& a, const symbol& b ) {
         return a.value < b.value;
      }

   private:
      uint64_t value = 0;
   };

   template<typename DataStream>
   inline DataStream& operator<<(DataStream& ds, const eosio::symbol sym) {
     uint64_t raw = sym.raw();
     ds.write( (const char*)&raw, sizeof(raw));
     return ds;
   }

   template<typename DataStream>
   inline DataStream& operator>>(DataStream& ds, eosio::symbol& sym) {
     uint64_t raw = 0;
     ds.read((char*)&raw, sizeof(raw));
     sym = symbol(raw);
     return ds;
   }

   class extended_symbol
   {
   public:

      constexpr extended_symbol() {}

      constexpr extended_symbol( symbol s, name con ) : sym(s), contract(con) {}

      constexpr symbol get_symbol() const { return sym; }

      constexpr name  get_contract() const { return contract; }

      void print( bool show_precision = true )const {
         sym.print( show_precision );
         ::eosio::print("@", contract);
      }

      friend constexpr bool operator == ( const extended_symbol& a, const extended_symbol& b ) {
        return std::tie( a.sym, a.contract ) == std::tie( b.sym, b.contract );
      }

      friend constexpr bool operator != ( const extended_symbol& a, const extended_symbol& b ) {
        return std::tie( a.sym, a.contract ) != std::tie( b.sym, b.contract );
      }

      friend constexpr bool operator < ( const extended_symbol& a, const extended_symbol& b ) {
        return std::tie( a.sym, a.contract ) < std::tie( b.sym, b.contract );
      }

   private:
      symbol sym; 
      name   contract; 

      EOSLIB_SERIALIZE( extended_symbol, (sym)(contract) )
   };
}

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Updated on 2022-12-05 at 15:38:08 +0000