mudgangster

Tiny, scriptable MUD client
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lobject.h (14492B)


      1 /*
      2 ** $Id: lobject.h,v 2.117.1.1 2017/04/19 17:39:34 roberto Exp $
      3 ** Type definitions for Lua objects
      4 ** See Copyright Notice in lua.h
      5 */
      6 
      7 
      8 #ifndef lobject_h
      9 #define lobject_h
     10 
     11 
     12 #include <stdarg.h>
     13 
     14 
     15 #include "llimits.h"
     16 #include "lua.h"
     17 
     18 
     19 /*
     20 ** Extra tags for non-values
     21 */
     22 #define LUA_TPROTO	LUA_NUMTAGS		/* function prototypes */
     23 #define LUA_TDEADKEY	(LUA_NUMTAGS+1)		/* removed keys in tables */
     24 
     25 /*
     26 ** number of all possible tags (including LUA_TNONE but excluding DEADKEY)
     27 */
     28 #define LUA_TOTALTAGS	(LUA_TPROTO + 2)
     29 
     30 
     31 /*
     32 ** tags for Tagged Values have the following use of bits:
     33 ** bits 0-3: actual tag (a LUA_T* value)
     34 ** bits 4-5: variant bits
     35 ** bit 6: whether value is collectable
     36 */
     37 
     38 
     39 /*
     40 ** LUA_TFUNCTION variants:
     41 ** 0 - Lua function
     42 ** 1 - light C function
     43 ** 2 - regular C function (closure)
     44 */
     45 
     46 /* Variant tags for functions */
     47 #define LUA_TLCL	(LUA_TFUNCTION | (0 << 4))  /* Lua closure */
     48 #define LUA_TLCF	(LUA_TFUNCTION | (1 << 4))  /* light C function */
     49 #define LUA_TCCL	(LUA_TFUNCTION | (2 << 4))  /* C closure */
     50 
     51 
     52 /* Variant tags for strings */
     53 #define LUA_TSHRSTR	(LUA_TSTRING | (0 << 4))  /* short strings */
     54 #define LUA_TLNGSTR	(LUA_TSTRING | (1 << 4))  /* long strings */
     55 
     56 
     57 /* Variant tags for numbers */
     58 #define LUA_TNUMFLT	(LUA_TNUMBER | (0 << 4))  /* float numbers */
     59 #define LUA_TNUMINT	(LUA_TNUMBER | (1 << 4))  /* integer numbers */
     60 
     61 
     62 /* Bit mark for collectable types */
     63 #define BIT_ISCOLLECTABLE	(1 << 6)
     64 
     65 /* mark a tag as collectable */
     66 #define ctb(t)			((t) | BIT_ISCOLLECTABLE)
     67 
     68 
     69 /*
     70 ** Common type for all collectable objects
     71 */
     72 typedef struct GCObject GCObject;
     73 
     74 
     75 /*
     76 ** Common Header for all collectable objects (in macro form, to be
     77 ** included in other objects)
     78 */
     79 #define CommonHeader	GCObject *next; lu_byte tt; lu_byte marked
     80 
     81 
     82 /*
     83 ** Common type has only the common header
     84 */
     85 struct GCObject {
     86   CommonHeader;
     87 };
     88 
     89 
     90 
     91 
     92 /*
     93 ** Tagged Values. This is the basic representation of values in Lua,
     94 ** an actual value plus a tag with its type.
     95 */
     96 
     97 /*
     98 ** Union of all Lua values
     99 */
    100 typedef union Value {
    101   GCObject *gc;    /* collectable objects */
    102   void *p;         /* light userdata */
    103   int b;           /* booleans */
    104   lua_CFunction f; /* light C functions */
    105   lua_Integer i;   /* integer numbers */
    106   lua_Number n;    /* float numbers */
    107 } Value;
    108 
    109 
    110 #define TValuefields	Value value_; int tt_
    111 
    112 
    113 typedef struct lua_TValue {
    114   TValuefields;
    115 } TValue;
    116 
    117 
    118 
    119 /* macro defining a nil value */
    120 #define NILCONSTANT	{NULL}, LUA_TNIL
    121 
    122 
    123 #define val_(o)		((o)->value_)
    124 
    125 
    126 /* raw type tag of a TValue */
    127 #define rttype(o)	((o)->tt_)
    128 
    129 /* tag with no variants (bits 0-3) */
    130 #define novariant(x)	((x) & 0x0F)
    131 
    132 /* type tag of a TValue (bits 0-3 for tags + variant bits 4-5) */
    133 #define ttype(o)	(rttype(o) & 0x3F)
    134 
    135 /* type tag of a TValue with no variants (bits 0-3) */
    136 #define ttnov(o)	(novariant(rttype(o)))
    137 
    138 
    139 /* Macros to test type */
    140 #define checktag(o,t)		(rttype(o) == (t))
    141 #define checktype(o,t)		(ttnov(o) == (t))
    142 #define ttisnumber(o)		checktype((o), LUA_TNUMBER)
    143 #define ttisfloat(o)		checktag((o), LUA_TNUMFLT)
    144 #define ttisinteger(o)		checktag((o), LUA_TNUMINT)
    145 #define ttisnil(o)		checktag((o), LUA_TNIL)
    146 #define ttisboolean(o)		checktag((o), LUA_TBOOLEAN)
    147 #define ttislightuserdata(o)	checktag((o), LUA_TLIGHTUSERDATA)
    148 #define ttisstring(o)		checktype((o), LUA_TSTRING)
    149 #define ttisshrstring(o)	checktag((o), ctb(LUA_TSHRSTR))
    150 #define ttislngstring(o)	checktag((o), ctb(LUA_TLNGSTR))
    151 #define ttistable(o)		checktag((o), ctb(LUA_TTABLE))
    152 #define ttisfunction(o)		checktype(o, LUA_TFUNCTION)
    153 #define ttisclosure(o)		((rttype(o) & 0x1F) == LUA_TFUNCTION)
    154 #define ttisCclosure(o)		checktag((o), ctb(LUA_TCCL))
    155 #define ttisLclosure(o)		checktag((o), ctb(LUA_TLCL))
    156 #define ttislcf(o)		checktag((o), LUA_TLCF)
    157 #define ttisfulluserdata(o)	checktag((o), ctb(LUA_TUSERDATA))
    158 #define ttisthread(o)		checktag((o), ctb(LUA_TTHREAD))
    159 #define ttisdeadkey(o)		checktag((o), LUA_TDEADKEY)
    160 
    161 
    162 /* Macros to access values */
    163 #define ivalue(o)	check_exp(ttisinteger(o), val_(o).i)
    164 #define fltvalue(o)	check_exp(ttisfloat(o), val_(o).n)
    165 #define nvalue(o)	check_exp(ttisnumber(o), \
    166 	(ttisinteger(o) ? cast_num(ivalue(o)) : fltvalue(o)))
    167 #define gcvalue(o)	check_exp(iscollectable(o), val_(o).gc)
    168 #define pvalue(o)	check_exp(ttislightuserdata(o), val_(o).p)
    169 #define tsvalue(o)	check_exp(ttisstring(o), gco2ts(val_(o).gc))
    170 #define uvalue(o)	check_exp(ttisfulluserdata(o), gco2u(val_(o).gc))
    171 #define clvalue(o)	check_exp(ttisclosure(o), gco2cl(val_(o).gc))
    172 #define clLvalue(o)	check_exp(ttisLclosure(o), gco2lcl(val_(o).gc))
    173 #define clCvalue(o)	check_exp(ttisCclosure(o), gco2ccl(val_(o).gc))
    174 #define fvalue(o)	check_exp(ttislcf(o), val_(o).f)
    175 #define hvalue(o)	check_exp(ttistable(o), gco2t(val_(o).gc))
    176 #define bvalue(o)	check_exp(ttisboolean(o), val_(o).b)
    177 #define thvalue(o)	check_exp(ttisthread(o), gco2th(val_(o).gc))
    178 /* a dead value may get the 'gc' field, but cannot access its contents */
    179 #define deadvalue(o)	check_exp(ttisdeadkey(o), cast(void *, val_(o).gc))
    180 
    181 #define l_isfalse(o)	(ttisnil(o) || (ttisboolean(o) && bvalue(o) == 0))
    182 
    183 
    184 #define iscollectable(o)	(rttype(o) & BIT_ISCOLLECTABLE)
    185 
    186 
    187 /* Macros for internal tests */
    188 #define righttt(obj)		(ttype(obj) == gcvalue(obj)->tt)
    189 
    190 #define checkliveness(L,obj) \
    191 	lua_longassert(!iscollectable(obj) || \
    192 		(righttt(obj) && (L == NULL || !isdead(G(L),gcvalue(obj)))))
    193 
    194 
    195 /* Macros to set values */
    196 #define settt_(o,t)	((o)->tt_=(t))
    197 
    198 #define setfltvalue(obj,x) \
    199   { TValue *io=(obj); val_(io).n=(x); settt_(io, LUA_TNUMFLT); }
    200 
    201 #define chgfltvalue(obj,x) \
    202   { TValue *io=(obj); lua_assert(ttisfloat(io)); val_(io).n=(x); }
    203 
    204 #define setivalue(obj,x) \
    205   { TValue *io=(obj); val_(io).i=(x); settt_(io, LUA_TNUMINT); }
    206 
    207 #define chgivalue(obj,x) \
    208   { TValue *io=(obj); lua_assert(ttisinteger(io)); val_(io).i=(x); }
    209 
    210 #define setnilvalue(obj) settt_(obj, LUA_TNIL)
    211 
    212 #define setfvalue(obj,x) \
    213   { TValue *io=(obj); val_(io).f=(x); settt_(io, LUA_TLCF); }
    214 
    215 #define setpvalue(obj,x) \
    216   { TValue *io=(obj); val_(io).p=(x); settt_(io, LUA_TLIGHTUSERDATA); }
    217 
    218 #define setbvalue(obj,x) \
    219   { TValue *io=(obj); val_(io).b=(x); settt_(io, LUA_TBOOLEAN); }
    220 
    221 #define setgcovalue(L,obj,x) \
    222   { TValue *io = (obj); GCObject *i_g=(x); \
    223     val_(io).gc = i_g; settt_(io, ctb(i_g->tt)); }
    224 
    225 #define setsvalue(L,obj,x) \
    226   { TValue *io = (obj); TString *x_ = (x); \
    227     val_(io).gc = obj2gco(x_); settt_(io, ctb(x_->tt)); \
    228     checkliveness(L,io); }
    229 
    230 #define setuvalue(L,obj,x) \
    231   { TValue *io = (obj); Udata *x_ = (x); \
    232     val_(io).gc = obj2gco(x_); settt_(io, ctb(LUA_TUSERDATA)); \
    233     checkliveness(L,io); }
    234 
    235 #define setthvalue(L,obj,x) \
    236   { TValue *io = (obj); lua_State *x_ = (x); \
    237     val_(io).gc = obj2gco(x_); settt_(io, ctb(LUA_TTHREAD)); \
    238     checkliveness(L,io); }
    239 
    240 #define setclLvalue(L,obj,x) \
    241   { TValue *io = (obj); LClosure *x_ = (x); \
    242     val_(io).gc = obj2gco(x_); settt_(io, ctb(LUA_TLCL)); \
    243     checkliveness(L,io); }
    244 
    245 #define setclCvalue(L,obj,x) \
    246   { TValue *io = (obj); CClosure *x_ = (x); \
    247     val_(io).gc = obj2gco(x_); settt_(io, ctb(LUA_TCCL)); \
    248     checkliveness(L,io); }
    249 
    250 #define sethvalue(L,obj,x) \
    251   { TValue *io = (obj); Table *x_ = (x); \
    252     val_(io).gc = obj2gco(x_); settt_(io, ctb(LUA_TTABLE)); \
    253     checkliveness(L,io); }
    254 
    255 #define setdeadvalue(obj)	settt_(obj, LUA_TDEADKEY)
    256 
    257 
    258 
    259 #define setobj(L,obj1,obj2) \
    260 	{ TValue *io1=(obj1); *io1 = *(obj2); \
    261 	  (void)L; checkliveness(L,io1); }
    262 
    263 
    264 /*
    265 ** different types of assignments, according to destination
    266 */
    267 
    268 /* from stack to (same) stack */
    269 #define setobjs2s	setobj
    270 /* to stack (not from same stack) */
    271 #define setobj2s	setobj
    272 #define setsvalue2s	setsvalue
    273 #define sethvalue2s	sethvalue
    274 #define setptvalue2s	setptvalue
    275 /* from table to same table */
    276 #define setobjt2t	setobj
    277 /* to new object */
    278 #define setobj2n	setobj
    279 #define setsvalue2n	setsvalue
    280 
    281 /* to table (define it as an expression to be used in macros) */
    282 #define setobj2t(L,o1,o2)  ((void)L, *(o1)=*(o2), checkliveness(L,(o1)))
    283 
    284 
    285 
    286 
    287 /*
    288 ** {======================================================
    289 ** types and prototypes
    290 ** =======================================================
    291 */
    292 
    293 
    294 typedef TValue *StkId;  /* index to stack elements */
    295 
    296 
    297 
    298 
    299 /*
    300 ** Header for string value; string bytes follow the end of this structure
    301 ** (aligned according to 'UTString'; see next).
    302 */
    303 typedef struct TString {
    304   CommonHeader;
    305   lu_byte extra;  /* reserved words for short strings; "has hash" for longs */
    306   lu_byte shrlen;  /* length for short strings */
    307   unsigned int hash;
    308   union {
    309     size_t lnglen;  /* length for long strings */
    310     struct TString *hnext;  /* linked list for hash table */
    311   } u;
    312 } TString;
    313 
    314 
    315 /*
    316 ** Ensures that address after this type is always fully aligned.
    317 */
    318 typedef union UTString {
    319   L_Umaxalign dummy;  /* ensures maximum alignment for strings */
    320   TString tsv;
    321 } UTString;
    322 
    323 
    324 /*
    325 ** Get the actual string (array of bytes) from a 'TString'.
    326 ** (Access to 'extra' ensures that value is really a 'TString'.)
    327 */
    328 #define getstr(ts)  \
    329   check_exp(sizeof((ts)->extra), cast(char *, (ts)) + sizeof(UTString))
    330 
    331 
    332 /* get the actual string (array of bytes) from a Lua value */
    333 #define svalue(o)       getstr(tsvalue(o))
    334 
    335 /* get string length from 'TString *s' */
    336 #define tsslen(s)	((s)->tt == LUA_TSHRSTR ? (s)->shrlen : (s)->u.lnglen)
    337 
    338 /* get string length from 'TValue *o' */
    339 #define vslen(o)	tsslen(tsvalue(o))
    340 
    341 
    342 /*
    343 ** Header for userdata; memory area follows the end of this structure
    344 ** (aligned according to 'UUdata'; see next).
    345 */
    346 typedef struct Udata {
    347   CommonHeader;
    348   lu_byte ttuv_;  /* user value's tag */
    349   struct Table *metatable;
    350   size_t len;  /* number of bytes */
    351   union Value user_;  /* user value */
    352 } Udata;
    353 
    354 
    355 /*
    356 ** Ensures that address after this type is always fully aligned.
    357 */
    358 typedef union UUdata {
    359   L_Umaxalign dummy;  /* ensures maximum alignment for 'local' udata */
    360   Udata uv;
    361 } UUdata;
    362 
    363 
    364 /*
    365 **  Get the address of memory block inside 'Udata'.
    366 ** (Access to 'ttuv_' ensures that value is really a 'Udata'.)
    367 */
    368 #define getudatamem(u)  \
    369   check_exp(sizeof((u)->ttuv_), (cast(char*, (u)) + sizeof(UUdata)))
    370 
    371 #define setuservalue(L,u,o) \
    372 	{ const TValue *io=(o); Udata *iu = (u); \
    373 	  iu->user_ = io->value_; iu->ttuv_ = rttype(io); \
    374 	  checkliveness(L,io); }
    375 
    376 
    377 #define getuservalue(L,u,o) \
    378 	{ TValue *io=(o); const Udata *iu = (u); \
    379 	  io->value_ = iu->user_; settt_(io, iu->ttuv_); \
    380 	  checkliveness(L,io); }
    381 
    382 
    383 /*
    384 ** Description of an upvalue for function prototypes
    385 */
    386 typedef struct Upvaldesc {
    387   TString *name;  /* upvalue name (for debug information) */
    388   lu_byte instack;  /* whether it is in stack (register) */
    389   lu_byte idx;  /* index of upvalue (in stack or in outer function's list) */
    390 } Upvaldesc;
    391 
    392 
    393 /*
    394 ** Description of a local variable for function prototypes
    395 ** (used for debug information)
    396 */
    397 typedef struct LocVar {
    398   TString *varname;
    399   int startpc;  /* first point where variable is active */
    400   int endpc;    /* first point where variable is dead */
    401 } LocVar;
    402 
    403 
    404 /*
    405 ** Function Prototypes
    406 */
    407 typedef struct Proto {
    408   CommonHeader;
    409   lu_byte numparams;  /* number of fixed parameters */
    410   lu_byte is_vararg;
    411   lu_byte maxstacksize;  /* number of registers needed by this function */
    412   int sizeupvalues;  /* size of 'upvalues' */
    413   int sizek;  /* size of 'k' */
    414   int sizecode;
    415   int sizelineinfo;
    416   int sizep;  /* size of 'p' */
    417   int sizelocvars;
    418   int linedefined;  /* debug information  */
    419   int lastlinedefined;  /* debug information  */
    420   TValue *k;  /* constants used by the function */
    421   Instruction *code;  /* opcodes */
    422   struct Proto **p;  /* functions defined inside the function */
    423   int *lineinfo;  /* map from opcodes to source lines (debug information) */
    424   LocVar *locvars;  /* information about local variables (debug information) */
    425   Upvaldesc *upvalues;  /* upvalue information */
    426   struct LClosure *cache;  /* last-created closure with this prototype */
    427   TString  *source;  /* used for debug information */
    428   GCObject *gclist;
    429 } Proto;
    430 
    431 
    432 
    433 /*
    434 ** Lua Upvalues
    435 */
    436 typedef struct UpVal UpVal;
    437 
    438 
    439 /*
    440 ** Closures
    441 */
    442 
    443 #define ClosureHeader \
    444 	CommonHeader; lu_byte nupvalues; GCObject *gclist
    445 
    446 typedef struct CClosure {
    447   ClosureHeader;
    448   lua_CFunction f;
    449   TValue upvalue[1];  /* list of upvalues */
    450 } CClosure;
    451 
    452 
    453 typedef struct LClosure {
    454   ClosureHeader;
    455   struct Proto *p;
    456   UpVal *upvals[1];  /* list of upvalues */
    457 } LClosure;
    458 
    459 
    460 typedef union Closure {
    461   CClosure c;
    462   LClosure l;
    463 } Closure;
    464 
    465 
    466 #define isLfunction(o)	ttisLclosure(o)
    467 
    468 #define getproto(o)	(clLvalue(o)->p)
    469 
    470 
    471 /*
    472 ** Tables
    473 */
    474 
    475 typedef union TKey {
    476   struct {
    477     TValuefields;
    478     int next;  /* for chaining (offset for next node) */
    479   } nk;
    480   TValue tvk;
    481 } TKey;
    482 
    483 
    484 /* copy a value into a key without messing up field 'next' */
    485 #define setnodekey(L,key,obj) \
    486 	{ TKey *k_=(key); const TValue *io_=(obj); \
    487 	  k_->nk.value_ = io_->value_; k_->nk.tt_ = io_->tt_; \
    488 	  (void)L; checkliveness(L,io_); }
    489 
    490 
    491 typedef struct Node {
    492   TValue i_val;
    493   TKey i_key;
    494 } Node;
    495 
    496 
    497 typedef struct Table {
    498   CommonHeader;
    499   lu_byte flags;  /* 1<<p means tagmethod(p) is not present */
    500   lu_byte lsizenode;  /* log2 of size of 'node' array */
    501   unsigned int sizearray;  /* size of 'array' array */
    502   TValue *array;  /* array part */
    503   Node *node;
    504   Node *lastfree;  /* any free position is before this position */
    505   struct Table *metatable;
    506   GCObject *gclist;
    507 } Table;
    508 
    509 
    510 
    511 /*
    512 ** 'module' operation for hashing (size is always a power of 2)
    513 */
    514 #define lmod(s,size) \
    515 	(check_exp((size&(size-1))==0, (cast(int, (s) & ((size)-1)))))
    516 
    517 
    518 #define twoto(x)	(1<<(x))
    519 #define sizenode(t)	(twoto((t)->lsizenode))
    520 
    521 
    522 /*
    523 ** (address of) a fixed nil value
    524 */
    525 #define luaO_nilobject		(&luaO_nilobject_)
    526 
    527 
    528 LUAI_DDEC const TValue luaO_nilobject_;
    529 
    530 /* size of buffer for 'luaO_utf8esc' function */
    531 #define UTF8BUFFSZ	8
    532 
    533 LUAI_FUNC int luaO_int2fb (unsigned int x);
    534 LUAI_FUNC int luaO_fb2int (int x);
    535 LUAI_FUNC int luaO_utf8esc (char *buff, unsigned long x);
    536 LUAI_FUNC int luaO_ceillog2 (unsigned int x);
    537 LUAI_FUNC void luaO_arith (lua_State *L, int op, const TValue *p1,
    538                            const TValue *p2, TValue *res);
    539 LUAI_FUNC size_t luaO_str2num (const char *s, TValue *o);
    540 LUAI_FUNC int luaO_hexavalue (int c);
    541 LUAI_FUNC void luaO_tostring (lua_State *L, StkId obj);
    542 LUAI_FUNC const char *luaO_pushvfstring (lua_State *L, const char *fmt,
    543                                                        va_list argp);
    544 LUAI_FUNC const char *luaO_pushfstring (lua_State *L, const char *fmt, ...);
    545 LUAI_FUNC void luaO_chunkid (char *out, const char *source, size_t len);
    546 
    547 
    548 #endif
    549