/*

** $Id: lobject.h,v 2.20.1.2 2008/08/06 13:29:48 roberto Exp $

** Type definitions for Lua objects

** See Copyright Notice in lua.h

*/

#ifndef lobject_h

#define lobject_h

#include <stdarg.h>

#include "llimits.h"

#include "lua.h"

/* tags for values visible from Lua */

#define LAST_TAG	LUA_TTHREAD

#define NUM_TAGS	(LAST_TAG+1)

/*

** Extra tags for non-values

*/

#define LUA_TPROTO	(LAST_TAG+1)

#define LUA_TUPVAL	(LAST_TAG+2)

#define LUA_TDEADKEY	(LAST_TAG+3)

/*

** Union of all collectable objects

*/

typedef union GCObject GCObject;

/*

** Common Header for all collectable objects (in macro form, to be

** included in other objects)

*/

#define CommonHeader	GCObject *next; lu_byte tt; lu_byte marked

/*

** Common header in struct form

*/

typedef struct GCheader {

  CommonHeader;

} GCheader;

/*

** Union of all Lua values

*/

typedef union {

  GCObject *gc;

  void *p;

  lua_Number n;

  int b;

} Value;

/*

** Tagged Values

*/

#define TValuefields	Value value; int tt

typedef struct lua_TValue {

  TValuefields;

} TValue;

/* Macros to test type */

#define ttisnil(o)	(ttype(o) == LUA_TNIL)

#define ttisnumber(o)	(ttype(o) == LUA_TNUMBER)

#define ttisstring(o)	(ttype(o) == LUA_TSTRING)

#define ttistable(o)	(ttype(o) == LUA_TTABLE)

#define ttisfunction(o)	(ttype(o) == LUA_TFUNCTION)

#define ttisboolean(o)	(ttype(o) == LUA_TBOOLEAN)

#define ttisuserdata(o)	(ttype(o) == LUA_TUSERDATA)

#define ttisthread(o)	(ttype(o) == LUA_TTHREAD)

#define ttislightuserdata(o)	(ttype(o) == LUA_TLIGHTUSERDATA)

/* Macros to access values */

#define ttype(o)	((o)->tt)

#define gcvalue(o)	check_exp(iscollectable(o), (o)->value.gc)

#define pvalue(o)	check_exp(ttislightuserdata(o), (o)->value.p)

#define nvalue(o)	check_exp(ttisnumber(o), (o)->value.n)

#define rawtsvalue(o)	check_exp(ttisstring(o), &(o)->value.gc->ts)

#define tsvalue(o)	(&rawtsvalue(o)->tsv)

#define rawuvalue(o)	check_exp(ttisuserdata(o), &(o)->value.gc->u)

#define uvalue(o)	(&rawuvalue(o)->uv)

#define clvalue(o)	check_exp(ttisfunction(o), &(o)->value.gc->cl)

#define hvalue(o)	check_exp(ttistable(o), &(o)->value.gc->h)

#define bvalue(o)	check_exp(ttisboolean(o), (o)->value.b)

#define thvalue(o)	check_exp(ttisthread(o), &(o)->value.gc->th)

#define l_isfalse(o)	(ttisnil(o) || (ttisboolean(o) && bvalue(o) == 0))

/*

** for internal debug only

*/

#define checkconsistency(obj) \

  lua_assert(!iscollectable(obj) || (ttype(obj) == (obj)->value.gc->gch.tt))

#define checkliveness(g,obj) \

  lua_assert(!iscollectable(obj) || \

  ((ttype(obj) == (obj)->value.gc->gch.tt) && !isdead(g, (obj)->value.gc)))

/* Macros to set values */

#define setnilvalue(obj) ((obj)->tt=LUA_TNIL)

#define setnvalue(obj,x) \

  { TValue *i_o=(obj); i_o->value.n=(x); i_o->tt=LUA_TNUMBER; }

#define setpvalue(obj,x) \

  { TValue *i_o=(obj); i_o->value.p=(x); i_o->tt=LUA_TLIGHTUSERDATA; }

#define setbvalue(obj,x) \

  { TValue *i_o=(obj); i_o->value.b=(x); i_o->tt=LUA_TBOOLEAN; }

#define setsvalue(L,obj,x) \

  { TValue *i_o=(obj); \

    i_o->value.gc=cast(GCObject *, (x)); i_o->tt=LUA_TSTRING; \

    checkliveness(G(L),i_o); }

#define setuvalue(L,obj,x) \

  { TValue *i_o=(obj); \

    i_o->value.gc=cast(GCObject *, (x)); i_o->tt=LUA_TUSERDATA; \

    checkliveness(G(L),i_o); }

#define setthvalue(L,obj,x) \

  { TValue *i_o=(obj); \

    i_o->value.gc=cast(GCObject *, (x)); i_o->tt=LUA_TTHREAD; \

    checkliveness(G(L),i_o); }

#define setclvalue(L,obj,x) \

  { TValue *i_o=(obj); \

    i_o->value.gc=cast(GCObject *, (x)); i_o->tt=LUA_TFUNCTION; \

    checkliveness(G(L),i_o); }

#define sethvalue(L,obj,x) \

  { TValue *i_o=(obj); \

    i_o->value.gc=cast(GCObject *, (x)); i_o->tt=LUA_TTABLE; \

    checkliveness(G(L),i_o); }

#define setptvalue(L,obj,x) \

  { TValue *i_o=(obj); \

    i_o->value.gc=cast(GCObject *, (x)); i_o->tt=LUA_TPROTO; \

    checkliveness(G(L),i_o); }

#define setobj(L,obj1,obj2) \

  { const TValue *o2=(obj2); TValue *o1=(obj1); \

    o1->value = o2->value; o1->tt=o2->tt; \

    checkliveness(G(L),o1); }

/*

** different types of sets, according to destination

*/

/* from stack to (same) stack */

#define setobjs2s	setobj

/* to stack (not from same stack) */

#define setobj2s	setobj

#define setsvalue2s	setsvalue

#define sethvalue2s	sethvalue

#define setptvalue2s	setptvalue

/* from table to same table */

#define setobjt2t	setobj

/* to table */

#define setobj2t	setobj

/* to new object */

#define setobj2n	setobj

#define setsvalue2n	setsvalue

#define setttype(obj, tt) (ttype(obj) = (tt))

#define iscollectable(o)	(ttype(o) >= LUA_TSTRING)

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

/*

** String headers for string table

*/

typedef union TString {

  L_Umaxalign dummy;  /* ensures maximum alignment for strings */

  struct {

    CommonHeader;

    lu_byte reserved;

    unsigned int hash;

    size_t len;

  } tsv;

} TString;

#define getstr(ts)	cast(const char *, (ts) + 1)

#define svalue(o)       getstr(rawtsvalue(o))

typedef union Udata {

  L_Umaxalign dummy;  /* ensures maximum alignment for `local' udata */

  struct {

    CommonHeader;

    struct Table *metatable;

    struct Table *env;

    size_t len;

  } uv;

} Udata;

/*

** Function Prototypes

*/

typedef struct Proto {

  CommonHeader;

  TValue *k;  /* constants used by the function */

  Instruction *code;

  struct Proto **p;  /* functions defined inside the function */

  int *lineinfo;  /* map from opcodes to source lines */

  struct LocVar *locvars;  /* information about local variables */

  TString **upvalues;  /* upvalue names */

  TString  *source;

  int sizeupvalues;

  int sizek;  /* size of `k' */

  int sizecode;

  int sizelineinfo;

  int sizep;  /* size of `p' */

  int sizelocvars;

  int linedefined;

  int lastlinedefined;

  GCObject *gclist;

  lu_byte nups;  /* number of upvalues */

  lu_byte numparams;

  lu_byte is_vararg;

  lu_byte maxstacksize;

} Proto;

/* masks for new-style vararg */

#define VARARG_HASARG		1

#define VARARG_ISVARARG		2

#define VARARG_NEEDSARG		4

typedef struct LocVar {

  TString *varname;

  int startpc;  /* first point where variable is active */

  int endpc;    /* first point where variable is dead */

} LocVar;

/*

** Upvalues

*/

typedef struct UpVal {

  CommonHeader;

  TValue *v;  /* points to stack or to its own value */

  union {

    TValue value;  /* the value (when closed) */

    struct {  /* double linked list (when open) */

      struct UpVal *prev;

      struct UpVal *next;

    } l;

  } u;

} UpVal;

/*

** Closures

*/

#define ClosureHeader \

	CommonHeader; lu_byte isC; lu_byte nupvalues; GCObject *gclist; \

	struct Table *env

typedef struct CClosure {

  ClosureHeader;

  lua_CFunction f;

  TValue upvalue[1];

} CClosure;

typedef struct LClosure {

  ClosureHeader;

  struct Proto *p;

  UpVal *upvals[1];

} LClosure;

typedef union Closure {

  CClosure c;

  LClosure l;

} Closure;

#define iscfunction(o)	(ttype(o) == LUA_TFUNCTION && clvalue(o)->c.isC)

#define isLfunction(o)	(ttype(o) == LUA_TFUNCTION && !clvalue(o)->c.isC)

/*

** Tables

*/

typedef union TKey {

  struct {

    TValuefields;

    struct Node *next;  /* for chaining */

  } nk;

  TValue tvk;

} TKey;

typedef struct Node {

  TValue i_val;

  TKey i_key;

} Node;

typedef struct Table {

  CommonHeader;

  lu_byte flags;  /* 1<<p means tagmethod(p) is not present */ 

  lu_byte lsizenode;  /* log2 of size of `node' array */

  struct Table *metatable;

  TValue *array;  /* array part */

  Node *node;

  Node *lastfree;  /* any free position is before this position */

  GCObject *gclist;

  int sizearray;  /* size of `array' array */

} Table;

/*

** `module' operation for hashing (size is always a power of 2)

*/

#define lmod(s,size) \

	(check_exp((size&(size-1))==0, (cast(int, (s) & ((size)-1)))))

#define twoto(x)	(1<<(x))

#define sizenode(t)	(twoto((t)->lsizenode))

#define luaO_nilobject		(&luaO_nilobject_)

LUAI_DATA const TValue luaO_nilobject_;

#define ceillog2(x)	(luaO_log2((x)-1) + 1)

LUAI_FUNC int luaO_log2 (unsigned int x);

LUAI_FUNC int luaO_int2fb (unsigned int x);

LUAI_FUNC int luaO_fb2int (int x);

LUAI_FUNC int luaO_rawequalObj (const TValue *t1, const TValue *t2);

LUAI_FUNC int luaO_str2d (const char *s, lua_Number *result);

LUAI_FUNC const char *luaO_pushvfstring (lua_State *L, const char *fmt,

                                                       va_list argp);

LUAI_FUNC const char *luaO_pushfstring (lua_State *L, const char *fmt, ...);

LUAI_FUNC void luaO_chunkid (char *out, const char *source, size_t len);

#endif