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#include "oop.hpp"
#include "prelude.hpp"
#include "util/thread.hpp"
#include <string>
#include <vector>
#include <tr1/unordered_map>
/* SymbolTable provides a one-to-one map between a symbol ID
* and a string. The hashing algorithm used to generate a
* hashval from a string is not perfect. For instance, the
* strings "__uint_fast64_t" and "TkIF_MOD" generate the same
* hashval. SymbolTable handles this by first looking up a
* symbol ID for a string by the string's hashval and then
* comparing the candidate string with the stored string that
* corresponds to the possible symbol ID.
* When a symbol ID is generated, the string corresponding to
* that symbol ID is stored in a vector. The symbol ID is the
* index of that string in the vector. The symbol ID becomes
* a Symbol* by adding the tag value for symbols. (See builtin
* class Symbol::from_index and oop.hpp.)
namespace rubinius {
class Array;
class String;
class Symbol;
typedef std::vector<std::string> SymbolStrings;
typedef std::vector<std::size_t> SymbolIds;
typedef std::tr1::unordered_map<hashval, SymbolIds> SymbolMap;
class SymbolTable {
public: // Types
// We encode in the symbol some information about it, mostly
// what kind of prefix it has. This lets us ask questions
// easily about it without having to get the string representation
// and perform comparisons against the char data.
enum Kind {
typedef std::vector<Kind> SymbolKinds;
SymbolMap symbols;
SymbolStrings strings;
SymbolKinds kinds;
thread::SpinLock lock_;
size_t bytes_used_;
size_t& bytes_used() {
return bytes_used_;
Symbol* lookup(std::string str);
Symbol* lookup(STATE, std::string str);
Symbol* lookup(const char* str, size_t length);
Symbol* lookup(STATE, const char* str, size_t length);
Symbol* lookup(STATE, String* str);
String* lookup_string(STATE, const Symbol* sym);
const char* lookup_cstring(STATE, const Symbol* sym);
const char* lookup_cstring(const Symbol* sym);
std::string& lookup_cppstring(const Symbol* sym);
size_t size();
Array* all_as_array(STATE);
Kind kind(STATE, const Symbol* sym);
int byte_size();
size_t add(std::string str);
Kind detect_kind(const char* str, int size);
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