/*
** $Id: lstate.h,v 1.6 1997/12/17 20:48:58 roberto Exp roberto $
** Global State
** See Copyright Notice in lua.h
*/

#ifndef lstate_h
#define lstate_h

#include "lobject.h"


#define MAX_C_BLOCKS 10

#define GARBAGE_BLOCK 150


typedef int StkId;  /* index to stack elements */

struct Stack {
  TObject *top;
  TObject *stack;
  TObject *last;
};

struct C_Lua_Stack {
  StkId base;  /* when Lua calls C or C calls Lua, points to */
               /* the first slot after the last parameter. */
  StkId lua2C; /* points to first element of "array" lua2C */
  int num;     /* size of "array" lua2C */
};


typedef struct {
  int size;
  int nuse;  /* number of elements (including EMPTYs) */
  TaggedString **hash;
} stringtable;


struct ref {
  TObject o;
  enum {LOCK, HOLD, FREE, COLLECTED} status;
};


typedef struct LState {
  struct Stack stack;  /* Lua stack */
  struct C_Lua_Stack Cstack;  /* C2lua struct */
  void *errorJmp;  /* current error recover point */
  TObject errorim;  /* error tag method */
  GCnode rootproto;  /* list of all prototypes */
  GCnode rootcl;  /* list of all closures */
  GCnode roottable;  /* list of all tables */
  GCnode rootglobal;  /* list of strings with global values */
  stringtable *string_root;  /* array of hash tables for strings and udata */
  struct IM *IMtable;  /* table for tag methods */
  int IMtable_size;  /* size of IMtable */
  int last_tag;  /* last used tag in IMtable */
  struct FuncState *mainState, *currState;  /* point to local structs in yacc */
  struct LexState *lexstate;  /* point to local struct in yacc */
  struct ref *refArray;  /* locked objects */
  int refSize;  /* size of refArray */
  unsigned long GCthreshold;
  unsigned long nblocks;  /* number of 'blocks' currently allocated */
  char *Mbuffer;  /* global buffer */
  char *Mbuffbase;  /* current first position of Mbuffer */
  int Mbuffsize;  /* size of Mbuffer */
  int Mbuffnext;  /* next position to fill in Mbuffer */
  struct C_Lua_Stack Cblocks[MAX_C_BLOCKS];
  int numCblocks;  /* number of nested Cblocks */
} LState;


extern LState *lua_state;


#define L	lua_state


#endif