lua/lobject.h
Roberto Ierusalimschy 25b4e35ee8 new macros abstracting TValue representation (to easy change to
other representations)
2011-05-05 12:53:23 -03:00

449 lines
11 KiB
C

/*
** $Id: lobject.h,v 2.51 2011/05/04 17:04:06 roberto Exp roberto $
** 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"
/*
** Extra tags for non-values
*/
#define LUA_TPROTO LUA_NUMTAGS
#define LUA_TUPVAL (LUA_NUMTAGS+1)
#define LUA_TDEADKEY (LUA_NUMTAGS+2)
/*
** number of all possible tags (including LUA_TNONE but excluding DEADKEY)
*/
#define LUA_TOTALTAGS (LUA_TUPVAL+2)
/*
** tags for Tagged Values have the following use of bits:
** bits 0-3: actual tag (a LUA_T* value)
** bit 4: variant bit (for functions, means a light C function)
** bit 5: whether value is collectable
*/
/* Variant tag for light C functions */
#define BIT_ISVARIANT (1 << 4)
#define LUA_TLCF (LUA_TFUNCTION | BIT_ISVARIANT)
/* Bit mark for collectable types */
#define BIT_ISCOLLECTABLE (1 << 5)
/* mark a tag as collectable */
#define ctb(t) ((t) | BIT_ISCOLLECTABLE)
/*
** 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; /* collectable objects */
void *p; /* light userdata */
lua_Number n; /* numbers */
int b; /* booleans */
lua_CFunction f; /* light C functions */
} Value;
/*
** Tagged Values. This is the basic representation of values in Lua,
** an actual value plus a tag with its type.
*/
#define TValuefields Value value_; int tt_
typedef struct lua_TValue {
TValuefields;
} TValue;
/* macro defining a nil value */
#define NILCONSTANT {NULL}, LUA_TNIL
#define val_(o) ((o)->value_)
/* raw type tag of a TValue */
#define rttype(o) ((o)->tt_)
/* type tag of a TValue (bits 0-3 for tags + variant bit) */
#define ttype(o) (rttype(o) & 0x1F)
/* type tag of a TValue with no variants (bits 0-3) */
#define ttypenv(o) (rttype(o) & 0x0F)
/* Macros to test type */
#define ttisnumber(o) (rttype(o) == LUA_TNUMBER)
#define ttisnil(o) (rttype(o) == LUA_TNIL)
#define ttisboolean(o) (rttype(o) == LUA_TBOOLEAN)
#define ttislightuserdata(o) (rttype(o) == LUA_TLIGHTUSERDATA)
#define ttisstring(o) (rttype(o) == ctb(LUA_TSTRING))
#define ttistable(o) (rttype(o) == ctb(LUA_TTABLE))
#define ttisfunction(o) (ttypenv(o) == LUA_TFUNCTION)
#define ttisclosure(o) (rttype(o) == ctb(LUA_TFUNCTION))
#define ttislcf(o) (rttype(o) == LUA_TLCF)
#define ttisuserdata(o) (rttype(o) == ctb(LUA_TUSERDATA))
#define ttisthread(o) (rttype(o) == ctb(LUA_TTHREAD))
#define ttisdeadkey(o) (rttype(o) == ctb(LUA_TDEADKEY))
#define ttisequal(o1,o2) (rttype(o1) == rttype(o2))
/* Macros to access values */
#define nvalue(o) check_exp(ttisnumber(o), val_(o).n)
#define gcvalue(o) check_exp(iscollectable(o), val_(o).gc)
#define pvalue(o) check_exp(ttislightuserdata(o), val_(o).p)
#define rawtsvalue(o) check_exp(ttisstring(o), &val_(o).gc->ts)
#define tsvalue(o) (&rawtsvalue(o)->tsv)
#define rawuvalue(o) check_exp(ttisuserdata(o), &val_(o).gc->u)
#define uvalue(o) (&rawuvalue(o)->uv)
#define clvalue(o) check_exp(ttisclosure(o), &val_(o).gc->cl)
#define fvalue(o) check_exp(ttislcf(o), val_(o).f)
#define hvalue(o) check_exp(ttistable(o), &val_(o).gc->h)
#define bvalue(o) check_exp(ttisboolean(o), val_(o).b)
#define thvalue(o) check_exp(ttisthread(o), &val_(o).gc->th)
#define l_isfalse(o) (ttisnil(o) || (ttisboolean(o) && bvalue(o) == 0))
#define iscollectable(o) (rttype(o) & BIT_ISCOLLECTABLE)
/* Macros for internal tests */
#define righttt(obj) (ttype(obj) == gcvalue(obj)->gch.tt)
#define checkconsistency(obj) lua_assert(!iscollectable(obj) || righttt(obj))
#define checkliveness(g,obj) \
lua_assert(!iscollectable(obj) || (righttt(obj) && !isdead(g,gcvalue(obj))))
/* Macros to set values */
#define settt_(o,t) ((o)->tt_=(t))
#define setnvalue(obj,x) \
{ TValue *io=(obj); val_(io).n=(x); settt_(io, LUA_TNUMBER); }
#define changenvalue(o,x) check_exp(ttisnumber(o), val_(o).n=(x))
#define setnilvalue(obj) settt_(obj, LUA_TNIL)
#define setfvalue(obj,x) \
{ TValue *io=(obj); val_(io).f=(x); settt_(io, LUA_TLCF); }
#define setpvalue(obj,x) \
{ TValue *io=(obj); val_(io).p=(x); settt_(io, LUA_TLIGHTUSERDATA); }
#define setbvalue(obj,x) \
{ TValue *io=(obj); val_(io).b=(x); settt_(io, LUA_TBOOLEAN); }
#define setgcovalue(L,obj,x) \
{ TValue *io=(obj); GCObject *i_g=(x); \
val_(io).gc=i_g; settt_(io, ctb(gch(i_g)->tt)); }
#define setsvalue(L,obj,x) \
{ TValue *io=(obj); \
val_(io).gc=cast(GCObject *, (x)); settt_(io, ctb(LUA_TSTRING)); \
checkliveness(G(L),io); }
#define setuvalue(L,obj,x) \
{ TValue *io=(obj); \
val_(io).gc=cast(GCObject *, (x)); settt_(io, ctb(LUA_TUSERDATA)); \
checkliveness(G(L),io); }
#define setthvalue(L,obj,x) \
{ TValue *io=(obj); \
val_(io).gc=cast(GCObject *, (x)); settt_(io, ctb(LUA_TTHREAD)); \
checkliveness(G(L),io); }
#define setclvalue(L,obj,x) \
{ TValue *io=(obj); \
val_(io).gc=cast(GCObject *, (x)); settt_(io, ctb(LUA_TFUNCTION)); \
checkliveness(G(L),io); }
#define sethvalue(L,obj,x) \
{ TValue *io=(obj); \
val_(io).gc=cast(GCObject *, (x)); settt_(io, ctb(LUA_TTABLE)); \
checkliveness(G(L),io); }
#define setptvalue(L,obj,x) \
{ TValue *io=(obj); \
val_(io).gc=cast(GCObject *, (x)); settt_(io, ctb(LUA_TPROTO)); \
checkliveness(G(L),io); }
#define setdeadvalue(obj) settt_(obj, ctb(LUA_TDEADKEY))
#define setobj(L,obj1,obj2) \
{ const TValue *io2=(obj2); TValue *io1=(obj1); \
io1->value_ = io2->value_; io1->tt_ = io2->tt_; \
checkliveness(G(L),io1); }
/*
** different types of assignments, 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
typedef TValue *StkId; /* index to stack elements */
/*
** Header for string value; string bytes follow the end of this structure
*/
typedef union TString {
L_Umaxalign dummy; /* ensures maximum alignment for strings */
struct {
CommonHeader;
lu_byte reserved;
unsigned int hash;
size_t len; /* number of characters in string */
} tsv;
} TString;
/* get the actual string (array of bytes) from a TString */
#define getstr(ts) cast(const char *, (ts) + 1)
/* get the actual string (array of bytes) from a Lua value */
#define svalue(o) getstr(rawtsvalue(o))
/*
** Header for userdata; memory area follows the end of this structure
*/
typedef union Udata {
L_Umaxalign dummy; /* ensures maximum alignment for `local' udata */
struct {
CommonHeader;
struct Table *metatable;
struct Table *env;
size_t len; /* number of bytes */
} uv;
} Udata;
/*
** Description of an upvalue for function prototypes
*/
typedef struct Upvaldesc {
TString *name; /* upvalue name (for debug information) */
lu_byte instack; /* whether it is in stack */
lu_byte idx; /* index of upvalue (in stack or in outer function's list) */
} Upvaldesc;
/*
** Description of a local variable for function prototypes
** (used for debug information)
*/
typedef struct LocVar {
TString *varname;
int startpc; /* first point where variable is active */
int endpc; /* first point where variable is dead */
} LocVar;
/*
** 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 */
LocVar *locvars; /* information about local variables */
Upvaldesc *upvalues; /* upvalue information */
union Closure *cache; /* last created closure with this prototype */
TString *source;
int sizeupvalues; /* size of 'upvalues' */
int sizek; /* size of `k' */
int sizecode;
int sizelineinfo;
int sizep; /* size of `p' */
int sizelocvars;
int linedefined;
int lastlinedefined;
GCObject *gclist;
lu_byte numparams; /* number of fixed parameters */
lu_byte is_vararg;
lu_byte maxstacksize; /* maximum stack used by this function */
} Proto;
/*
** Lua 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
typedef struct CClosure {
ClosureHeader;
lua_CFunction f;
TValue upvalue[1]; /* list of upvalues */
} CClosure;
typedef struct LClosure {
ClosureHeader;
struct Proto *p;
UpVal *upvals[1]; /* list of upvalues */
} LClosure;
typedef union Closure {
CClosure c;
LClosure l;
} Closure;
#define isLfunction(o) (ttisclosure(o) && !clvalue(o)->c.isC)
#define getproto(o) (clvalue(o)->l.p)
/*
** 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))
/*
** (address of) a fixed nil value
*/
#define luaO_nilobject (&luaO_nilobject_)
LUAI_DDEC const TValue luaO_nilobject_;
LUAI_FUNC int luaO_int2fb (unsigned int x);
LUAI_FUNC int luaO_fb2int (int x);
LUAI_FUNC int luaO_ceillog2 (unsigned int x);
LUAI_FUNC lua_Number luaO_arith (int op, lua_Number v1, lua_Number v2);
LUAI_FUNC int luaO_rawequalObj (const TValue *t1, const TValue *t2);
LUAI_FUNC int luaO_str2d (const char *s, size_t len, lua_Number *result);
LUAI_FUNC int luaO_hexavalue (int c);
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