1 files changed, 787 insertions, 0 deletions

diff --git a/src/lua/lobject.h b/src/lua/lobject.h
new file mode 100644
index 0000000..04a81d3
--- /dev/null
+++ b/src/lua/lobject.h
@@ -0,0 +1,787 @@
+/*
+** $Id: lobject.h $
+** 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 types for collectable non-values
+*/
+#define LUA_TUPVAL      LUA_NUMTYPES  /* upvalues */
+#define LUA_TPROTO      (LUA_NUMTYPES+1)  /* function prototypes */
+
+
+/*
+** number of all possible types (including LUA_TNONE)
+*/
+#define LUA_TOTALTYPES          (LUA_TPROTO + 2)
+
+
+/*
+** tags for Tagged Values have the following use of bits:
+** bits 0-3: actual tag (a LUA_T* constant)
+** bits 4-5: variant bits
+** bit 6: whether value is collectable
+*/
+
+/* add variant bits to a type */
+#define makevariant(t,v)        ((t) | ((v) << 4))
+
+
+
+/*
+** Union of all Lua values
+*/
+typedef union Value {
+  struct GCObject *gc;    /* collectable objects */
+  void *p;         /* light userdata */
+  lua_CFunction f; /* light C functions */
+  lua_Integer i;   /* integer numbers */
+  lua_Number n;    /* float numbers */
+} 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_; lu_byte tt_
+
+typedef struct TValue {
+  TValuefields;
+} TValue;
+
+
+#define val_(o)         ((o)->value_)
+#define valraw(o)       (&val_(o))
+
+
+/* raw type tag of a TValue */
+#define rawtt(o)        ((o)->tt_)
+
+/* tag with no variants (bits 0-3) */
+#define novariant(t)    ((t) & 0x0F)
+
+/* type tag of a TValue (bits 0-3 for tags + variant bits 4-5) */
+#define withvariant(t)  ((t) & 0x3F)
+#define ttypetag(o)     withvariant(rawtt(o))
+
+/* type of a TValue */
+#define ttype(o)        (novariant(rawtt(o)))
+
+
+/* Macros to test type */
+#define checktag(o,t)           (rawtt(o) == (t))
+#define checktype(o,t)          (ttype(o) == (t))
+
+
+/* Macros for internal tests */
+
+/* collectable object has the same tag as the original value */
+#define righttt(obj)            (ttypetag(obj) == gcvalue(obj)->tt)
+
+/*
+** Any value being manipulated by the program either is non
+** collectable, or the collectable object has the right tag
+** and it is not dead.
+*/
+#define checkliveness(L,obj) \
+        ((void)L, lua_longassert(!iscollectable(obj) || \
+                (righttt(obj) && (L == NULL || !isdead(G(L),gcvalue(obj))))))
+
+
+/* Macros to set values */
+
+/* set a value's tag */
+#define settt_(o,t)     ((o)->tt_=(t))
+
+
+/* main macro to copy values (from 'obj1' to 'obj2') */
+#define setobj(L,obj1,obj2) \
+        { TValue *io1=(obj1); const TValue *io2=(obj2); \
+          io1->value_ = io2->value_; settt_(io1, io2->tt_); \
+          checkliveness(L,io1); lua_assert(!isnonstrictnil(io1)); }
+
+/*
+** Different types of assignments, according to source and destination.
+** (They are mostly equal now, but may be different in the future.)
+*/
+
+/* from stack to stack */
+#define setobjs2s(L,o1,o2)      setobj(L,s2v(o1),s2v(o2))
+/* to stack (not from same stack) */
+#define setobj2s(L,o1,o2)       setobj(L,s2v(o1),o2)
+/* from table to same table */
+#define setobjt2t       setobj
+/* to new object */
+#define setobj2n        setobj
+/* to table */
+#define setobj2t        setobj
+
+
+/*
+** Entries in the Lua stack
+*/
+typedef union StackValue {
+  TValue val;
+} StackValue;
+
+
+/* index to stack elements */
+typedef StackValue *StkId;
+
+/* convert a 'StackValue' to a 'TValue' */
+#define s2v(o)  (&(o)->val)
+
+
+
+/*
+** {==================================================================
+** Nil
+** ===================================================================
+*/
+
+/* Standard nil */
+#define LUA_VNIL        makevariant(LUA_TNIL, 0)
+
+/* Empty slot (which might be different from a slot containing nil) */
+#define LUA_VEMPTY      makevariant(LUA_TNIL, 1)
+
+/* Value returned for a key not found in a table (absent key) */
+#define LUA_VABSTKEY    makevariant(LUA_TNIL, 2)
+
+
+/* macro to test for (any kind of) nil */
+#define ttisnil(v)              checktype((v), LUA_TNIL)
+
+
+/* macro to test for a standard nil */
+#define ttisstrictnil(o)        checktag((o), LUA_VNIL)
+
+
+#define setnilvalue(obj) settt_(obj, LUA_VNIL)
+
+
+#define isabstkey(v)            checktag((v), LUA_VABSTKEY)
+
+
+/*
+** macro to detect non-standard nils (used only in assertions)
+*/
+#define isnonstrictnil(v)       (ttisnil(v) && !ttisstrictnil(v))
+
+
+/*
+** By default, entries with any kind of nil are considered empty.
+** (In any definition, values associated with absent keys must also
+** be accepted as empty.)
+*/
+#define isempty(v)              ttisnil(v)
+
+
+/* macro defining a value corresponding to an absent key */
+#define ABSTKEYCONSTANT         {NULL}, LUA_VABSTKEY
+
+
+/* mark an entry as empty */
+#define setempty(v)             settt_(v, LUA_VEMPTY)
+
+
+
+/* }================================================================== */
+
+
+/*
+** {==================================================================
+** Booleans
+** ===================================================================
+*/
+
+
+#define LUA_VFALSE      makevariant(LUA_TBOOLEAN, 0)
+#define LUA_VTRUE       makevariant(LUA_TBOOLEAN, 1)
+
+#define ttisboolean(o)          checktype((o), LUA_TBOOLEAN)
+#define ttisfalse(o)            checktag((o), LUA_VFALSE)
+#define ttistrue(o)             checktag((o), LUA_VTRUE)
+
+
+#define l_isfalse(o)    (ttisfalse(o) || ttisnil(o))
+
+
+#define setbfvalue(obj)         settt_(obj, LUA_VFALSE)
+#define setbtvalue(obj)         settt_(obj, LUA_VTRUE)
+
+/* }================================================================== */
+
+
+/*
+** {==================================================================
+** Threads
+** ===================================================================
+*/
+
+#define LUA_VTHREAD             makevariant(LUA_TTHREAD, 0)
+
+#define ttisthread(o)           checktag((o), ctb(LUA_VTHREAD))
+
+#define thvalue(o)      check_exp(ttisthread(o), gco2th(val_(o).gc))
+
+#define setthvalue(L,obj,x) \
+  { TValue *io = (obj); lua_State *x_ = (x); \
+    val_(io).gc = obj2gco(x_); settt_(io, ctb(LUA_VTHREAD)); \
+    checkliveness(L,io); }
+
+#define setthvalue2s(L,o,t)     setthvalue(L,s2v(o),t)
+
+/* }================================================================== */
+
+
+/*
+** {==================================================================
+** Collectable Objects
+** ===================================================================
+*/
+
+/*
+** Common Header for all collectable objects (in macro form, to be
+** included in other objects)
+*/
+#define CommonHeader    struct GCObject *next; lu_byte tt; lu_byte marked
+
+
+/* Common type for all collectable objects */
+typedef struct GCObject {
+  CommonHeader;
+} GCObject;
+
+
+/* Bit mark for collectable types */
+#define BIT_ISCOLLECTABLE       (1 << 6)
+
+#define iscollectable(o)        (rawtt(o) & BIT_ISCOLLECTABLE)
+
+/* mark a tag as collectable */
+#define ctb(t)                  ((t) | BIT_ISCOLLECTABLE)
+
+#define gcvalue(o)      check_exp(iscollectable(o), val_(o).gc)
+
+#define gcvalueraw(v)   ((v).gc)
+
+#define setgcovalue(L,obj,x) \
+  { TValue *io = (obj); GCObject *i_g=(x); \
+    val_(io).gc = i_g; settt_(io, ctb(i_g->tt)); }
+
+/* }================================================================== */
+
+
+/*
+** {==================================================================
+** Numbers
+** ===================================================================
+*/
+
+/* Variant tags for numbers */
+#define LUA_VNUMINT     makevariant(LUA_TNUMBER, 0)  /* integer numbers */
+#define LUA_VNUMFLT     makevariant(LUA_TNUMBER, 1)  /* float numbers */
+
+#define ttisnumber(o)           checktype((o), LUA_TNUMBER)
+#define ttisfloat(o)            checktag((o), LUA_VNUMFLT)
+#define ttisinteger(o)          checktag((o), LUA_VNUMINT)
+
+#define nvalue(o)       check_exp(ttisnumber(o), \
+        (ttisinteger(o) ? cast_num(ivalue(o)) : fltvalue(o)))
+#define fltvalue(o)     check_exp(ttisfloat(o), val_(o).n)
+#define ivalue(o)       check_exp(ttisinteger(o), val_(o).i)
+
+#define fltvalueraw(v)  ((v).n)
+#define ivalueraw(v)    ((v).i)
+
+#define setfltvalue(obj,x) \
+  { TValue *io=(obj); val_(io).n=(x); settt_(io, LUA_VNUMFLT); }
+
+#define chgfltvalue(obj,x) \
+  { TValue *io=(obj); lua_assert(ttisfloat(io)); val_(io).n=(x); }
+
+#define setivalue(obj,x) \
+  { TValue *io=(obj); val_(io).i=(x); settt_(io, LUA_VNUMINT); }
+
+#define chgivalue(obj,x) \
+  { TValue *io=(obj); lua_assert(ttisinteger(io)); val_(io).i=(x); }
+
+/* }================================================================== */
+
+
+/*
+** {==================================================================
+** Strings
+** ===================================================================
+*/
+
+/* Variant tags for strings */
+#define LUA_VSHRSTR     makevariant(LUA_TSTRING, 0)  /* short strings */
+#define LUA_VLNGSTR     makevariant(LUA_TSTRING, 1)  /* long strings */
+
+#define ttisstring(o)           checktype((o), LUA_TSTRING)
+#define ttisshrstring(o)        checktag((o), ctb(LUA_VSHRSTR))
+#define ttislngstring(o)        checktag((o), ctb(LUA_VLNGSTR))
+
+#define tsvalueraw(v)   (gco2ts((v).gc))
+
+#define tsvalue(o)      check_exp(ttisstring(o), gco2ts(val_(o).gc))
+
+#define setsvalue(L,obj,x) \
+  { TValue *io = (obj); TString *x_ = (x); \
+    val_(io).gc = obj2gco(x_); settt_(io, ctb(x_->tt)); \
+    checkliveness(L,io); }
+
+/* set a string to the stack */
+#define setsvalue2s(L,o,s)      setsvalue(L,s2v(o),s)
+
+/* set a string to a new object */
+#define setsvalue2n     setsvalue
+
+
+/*
+** Header for a string value.
+*/
+typedef struct TString {
+  CommonHeader;
+  lu_byte extra;  /* reserved words for short strings; "has hash" for longs */
+  lu_byte shrlen;  /* length for short strings */
+  unsigned int hash;
+  union {
+    size_t lnglen;  /* length for long strings */
+    struct TString *hnext;  /* linked list for hash table */
+  } u;
+  char contents[1];
+} TString;
+
+
+
+/*
+** Get the actual string (array of bytes) from a 'TString'.
+*/
+#define getstr(ts)  ((ts)->contents)
+
+
+/* get the actual string (array of bytes) from a Lua value */
+#define svalue(o)       getstr(tsvalue(o))
+
+/* get string length from 'TString *s' */
+#define tsslen(s)       ((s)->tt == LUA_VSHRSTR ? (s)->shrlen : (s)->u.lnglen)
+
+/* get string length from 'TValue *o' */
+#define vslen(o)        tsslen(tsvalue(o))
+
+/* }================================================================== */
+
+
+/*
+** {==================================================================
+** Userdata
+** ===================================================================
+*/
+
+
+/*
+** Light userdata should be a variant of userdata, but for compatibility
+** reasons they are also different types.
+*/
+#define LUA_VLIGHTUSERDATA      makevariant(LUA_TLIGHTUSERDATA, 0)
+
+#define LUA_VUSERDATA           makevariant(LUA_TUSERDATA, 0)
+
+#define ttislightuserdata(o)    checktag((o), LUA_VLIGHTUSERDATA)
+#define ttisfulluserdata(o)     checktag((o), ctb(LUA_VUSERDATA))
+
+#define pvalue(o)       check_exp(ttislightuserdata(o), val_(o).p)
+#define uvalue(o)       check_exp(ttisfulluserdata(o), gco2u(val_(o).gc))
+
+#define pvalueraw(v)    ((v).p)
+
+#define setpvalue(obj,x) \
+  { TValue *io=(obj); val_(io).p=(x); settt_(io, LUA_VLIGHTUSERDATA); }
+
+#define setuvalue(L,obj,x) \
+  { TValue *io = (obj); Udata *x_ = (x); \
+    val_(io).gc = obj2gco(x_); settt_(io, ctb(LUA_VUSERDATA)); \
+    checkliveness(L,io); }
+
+
+/* Ensures that addresses after this type are always fully aligned. */
+typedef union UValue {
+  TValue uv;
+  LUAI_MAXALIGN;  /* ensures maximum alignment for udata bytes */
+} UValue;
+
+
+/*
+** Header for userdata with user values;
+** memory area follows the end of this structure.
+*/
+typedef struct Udata {
+  CommonHeader;
+  unsigned short nuvalue;  /* number of user values */
+  size_t len;  /* number of bytes */
+  struct Table *metatable;
+  GCObject *gclist;
+  UValue uv[1];  /* user values */
+} Udata;
+
+
+/*
+** Header for userdata with no user values. These userdata do not need
+** to be gray during GC, and therefore do not need a 'gclist' field.
+** To simplify, the code always use 'Udata' for both kinds of userdata,
+** making sure it never accesses 'gclist' on userdata with no user values.
+** This structure here is used only to compute the correct size for
+** this representation. (The 'bindata' field in its end ensures correct
+** alignment for binary data following this header.)
+*/
+typedef struct Udata0 {
+  CommonHeader;
+  unsigned short nuvalue;  /* number of user values */
+  size_t len;  /* number of bytes */
+  struct Table *metatable;
+  union {LUAI_MAXALIGN;} bindata;
+} Udata0;
+
+
+/* compute the offset of the memory area of a userdata */
+#define udatamemoffset(nuv) \
+        ((nuv) == 0 ? offsetof(Udata0, bindata)  \
+                    : offsetof(Udata, uv) + (sizeof(UValue) * (nuv)))
+
+/* get the address of the memory block inside 'Udata' */
+#define getudatamem(u)  (cast_charp(u) + udatamemoffset((u)->nuvalue))
+
+/* compute the size of a userdata */
+#define sizeudata(nuv,nb)       (udatamemoffset(nuv) + (nb))
+
+/* }================================================================== */
+
+
+/*
+** {==================================================================
+** Prototypes
+** ===================================================================
+*/
+
+#define LUA_VPROTO      makevariant(LUA_TPROTO, 0)
+
+
+/*
+** 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 (register) */
+  lu_byte idx;  /* index of upvalue (in stack or in outer function's list) */
+  lu_byte kind;  /* kind of corresponding variable */
+} 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;
+
+
+/*
+** Associates the absolute line source for a given instruction ('pc').
+** The array 'lineinfo' gives, for each instruction, the difference in
+** lines from the previous instruction. When that difference does not
+** fit into a byte, Lua saves the absolute line for that instruction.
+** (Lua also saves the absolute line periodically, to speed up the
+** computation of a line number: we can use binary search in the
+** absolute-line array, but we must traverse the 'lineinfo' array
+** linearly to compute a line.)
+*/
+typedef struct AbsLineInfo {
+  int pc;
+  int line;
+} AbsLineInfo;
+
+/*
+** Function Prototypes
+*/
+typedef struct Proto {
+  CommonHeader;
+  lu_byte numparams;  /* number of fixed (named) parameters */
+  lu_byte is_vararg;
+  lu_byte maxstacksize;  /* number of registers needed by this function */
+  int sizeupvalues;  /* size of 'upvalues' */
+  int sizek;  /* size of 'k' */
+  int sizecode;
+  int sizelineinfo;
+  int sizep;  /* size of 'p' */
+  int sizelocvars;
+  int sizeabslineinfo;  /* size of 'abslineinfo' */
+  int linedefined;  /* debug information  */
+  int lastlinedefined;  /* debug information  */
+  TValue *k;  /* constants used by the function */
+  Instruction *code;  /* opcodes */
+  struct Proto **p;  /* functions defined inside the function */
+  Upvaldesc *upvalues;  /* upvalue information */
+  ls_byte *lineinfo;  /* information about source lines (debug information) */
+  AbsLineInfo *abslineinfo;  /* idem */
+  LocVar *locvars;  /* information about local variables (debug information) */
+  TString  *source;  /* used for debug information */
+  GCObject *gclist;
+} Proto;
+
+/* }================================================================== */
+
+
+/*
+** {==================================================================
+** Closures
+** ===================================================================
+*/
+
+#define LUA_VUPVAL      makevariant(LUA_TUPVAL, 0)
+
+
+/* Variant tags for functions */
+#define LUA_VLCL        makevariant(LUA_TFUNCTION, 0)  /* Lua closure */
+#define LUA_VLCF        makevariant(LUA_TFUNCTION, 1)  /* light C function */
+#define LUA_VCCL        makevariant(LUA_TFUNCTION, 2)  /* C closure */
+
+#define ttisfunction(o)         checktype(o, LUA_TFUNCTION)
+#define ttisclosure(o)          ((rawtt(o) & 0x1F) == LUA_VLCL)
+#define ttisLclosure(o)         checktag((o), ctb(LUA_VLCL))
+#define ttislcf(o)              checktag((o), LUA_VLCF)
+#define ttisCclosure(o)         checktag((o), ctb(LUA_VCCL))
+
+#define isLfunction(o)  ttisLclosure(o)
+
+#define clvalue(o)      check_exp(ttisclosure(o), gco2cl(val_(o).gc))
+#define clLvalue(o)     check_exp(ttisLclosure(o), gco2lcl(val_(o).gc))
+#define fvalue(o)       check_exp(ttislcf(o), val_(o).f)
+#define clCvalue(o)     check_exp(ttisCclosure(o), gco2ccl(val_(o).gc))
+
+#define fvalueraw(v)    ((v).f)
+
+#define setclLvalue(L,obj,x) \
+  { TValue *io = (obj); LClosure *x_ = (x); \
+    val_(io).gc = obj2gco(x_); settt_(io, ctb(LUA_VLCL)); \
+    checkliveness(L,io); }
+
+#define setclLvalue2s(L,o,cl)   setclLvalue(L,s2v(o),cl)
+
+#define setfvalue(obj,x) \
+  { TValue *io=(obj); val_(io).f=(x); settt_(io, LUA_VLCF); }
+
+#define setclCvalue(L,obj,x) \
+  { TValue *io = (obj); CClosure *x_ = (x); \
+    val_(io).gc = obj2gco(x_); settt_(io, ctb(LUA_VCCL)); \
+    checkliveness(L,io); }
+
+
+/*
+** Upvalues for Lua closures
+*/
+typedef struct UpVal {
+  CommonHeader;
+  lu_byte tbc;  /* true if it represents a to-be-closed variable */
+  TValue *v;  /* points to stack or to its own value */
+  union {
+    struct {  /* (when open) */
+      struct UpVal *next;  /* linked list */
+      struct UpVal **previous;
+    } open;
+    TValue value;  /* the value (when closed) */
+  } u;
+} UpVal;
+
+
+
+#define ClosureHeader \
+        CommonHeader; 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 getproto(o)     (clLvalue(o)->p)
+
+/* }================================================================== */
+
+
+/*
+** {==================================================================
+** Tables
+** ===================================================================
+*/
+
+#define LUA_VTABLE      makevariant(LUA_TTABLE, 0)
+
+#define ttistable(o)            checktag((o), ctb(LUA_VTABLE))
+
+#define hvalue(o)       check_exp(ttistable(o), gco2t(val_(o).gc))
+
+#define sethvalue(L,obj,x) \
+  { TValue *io = (obj); Table *x_ = (x); \
+    val_(io).gc = obj2gco(x_); settt_(io, ctb(LUA_VTABLE)); \
+    checkliveness(L,io); }
+
+#define sethvalue2s(L,o,h)      sethvalue(L,s2v(o),h)
+
+
+/*
+** Nodes for Hash tables: A pack of two TValue's (key-value pairs)
+** plus a 'next' field to link colliding entries. The distribution
+** of the key's fields ('key_tt' and 'key_val') not forming a proper
+** 'TValue' allows for a smaller size for 'Node' both in 4-byte
+** and 8-byte alignments.
+*/
+typedef union Node {
+  struct NodeKey {
+    TValuefields;  /* fields for value */
+    lu_byte key_tt;  /* key type */
+    int next;  /* for chaining */
+    Value key_val;  /* key value */
+  } u;
+  TValue i_val;  /* direct access to node's value as a proper 'TValue' */
+} Node;
+
+
+/* copy a value into a key */
+#define setnodekey(L,node,obj) \
+        { Node *n_=(node); const TValue *io_=(obj); \
+          n_->u.key_val = io_->value_; n_->u.key_tt = io_->tt_; \
+          checkliveness(L,io_); }
+
+
+/* copy a value from a key */
+#define getnodekey(L,obj,node) \
+        { TValue *io_=(obj); const Node *n_=(node); \
+          io_->value_ = n_->u.key_val; io_->tt_ = n_->u.key_tt; \
+          checkliveness(L,io_); }
+
+
+/*
+** About 'alimit': if 'isrealasize(t)' is true, then 'alimit' is the
+** real size of 'array'. Otherwise, the real size of 'array' is the
+** smallest power of two not smaller than 'alimit' (or zero iff 'alimit'
+** is zero); 'alimit' is then used as a hint for #t.
+*/
+
+#define BITRAS          (1 << 7)
+#define isrealasize(t)          (!((t)->marked & BITRAS))
+#define setrealasize(t)         ((t)->marked &= cast_byte(~BITRAS))
+#define setnorealasize(t)       ((t)->marked |= BITRAS)
+
+
+typedef struct Table {
+  CommonHeader;
+  lu_byte flags;  /* 1<<p means tagmethod(p) is not present */
+  lu_byte lsizenode;  /* log2 of size of 'node' array */
+  unsigned int alimit;  /* "limit" of 'array' array */
+  TValue *array;  /* array part */
+  Node *node;
+  Node *lastfree;  /* any free position is before this position */
+  struct Table *metatable;
+  GCObject *gclist;
+} Table;
+
+
+/*
+** Macros to manipulate keys inserted in nodes
+*/
+#define keytt(node)             ((node)->u.key_tt)
+#define keyval(node)            ((node)->u.key_val)
+
+#define keyisnil(node)          (keytt(node) == LUA_TNIL)
+#define keyisinteger(node)      (keytt(node) == LUA_VNUMINT)
+#define keyival(node)           (keyval(node).i)
+#define keyisshrstr(node)       (keytt(node) == ctb(LUA_VSHRSTR))
+#define keystrval(node)         (gco2ts(keyval(node).gc))
+
+#define setnilkey(node)         (keytt(node) = LUA_TNIL)
+
+#define keyiscollectable(n)     (keytt(n) & BIT_ISCOLLECTABLE)
+
+#define gckey(n)        (keyval(n).gc)
+#define gckeyN(n)       (keyiscollectable(n) ? gckey(n) : NULL)
+
+
+/*
+** Use a "nil table" to mark dead keys in a table. Those keys serve
+** to keep space for removed entries, which may still be part of
+** chains. Note that the 'keytt' does not have the BIT_ISCOLLECTABLE
+** set, so these values are considered not collectable and are different
+** from any valid value.
+*/
+#define setdeadkey(n)   (keytt(n) = LUA_TTABLE, gckey(n) = NULL)
+
+/* }================================================================== */
+
+
+
+/*
+** '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))
+
+
+/* size of buffer for 'luaO_utf8esc' function */
+#define UTF8BUFFSZ      8
+
+LUAI_FUNC int luaO_utf8esc (char *buff, unsigned long x);
+LUAI_FUNC int luaO_ceillog2 (unsigned int x);
+LUAI_FUNC int luaO_rawarith (lua_State *L, int op, const TValue *p1,
+                             const TValue *p2, TValue *res);
+LUAI_FUNC void luaO_arith (lua_State *L, int op, const TValue *p1,
+                           const TValue *p2, StkId res);
+LUAI_FUNC size_t luaO_str2num (const char *s, TValue *o);
+LUAI_FUNC int luaO_hexavalue (int c);
+LUAI_FUNC void luaO_tostring (lua_State *L, TValue *obj);
+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 srclen);
+
+
+#endif
+