1 files changed, 922 insertions, 922 deletions
diff --git a/lib/lua/src/lapi.c b/lib/lua/src/lapi.c
index 48646b9..038d5bf 100644
--- a/lib/lua/src/lapi.c
+++ b/lib/lua/src/lapi.c
@@ -1,922 +1,922 @@
-/*
-** $Id: lapi.c,v 1.3 2004-11-27 21:35:20 pixel Exp $
-** Lua API
-** See Copyright Notice in lua.h
-*/
-
-
-#include <assert.h>
-#include <string.h>
-
-#define lapi_c
-
-#include "lua.h"
-
-#include "lapi.h"
-#include "ldebug.h"
-#include "ldo.h"
-#include "lfunc.h"
-#include "lgc.h"
-#include "lmem.h"
-#include "lobject.h"
-#include "lstate.h"
-#include "lstring.h"
-#include "ltable.h"
-#include "ltm.h"
-#include "lundump.h"
-#include "lvm.h"
-
-
-const char lua_ident[] =
-  "$Lua: " LUA_VERSION " " LUA_COPYRIGHT " $\n"
-  "$Authors: " LUA_AUTHORS " $\n"
-  "$URL: www.lua.org $\n";
-
-
-
-#ifndef api_check
-#define api_check(L, o)		/*{ assert(o); }*/
-#endif
-
-#define api_checknelems(L, n)	api_check(L, (n) <= (L->top - L->base))
-
-#define api_incr_top(L)   {api_check(L, L->top < L->ci->top); L->top++;}
-
-
-
-
-static TObject *negindex (lua_State *L, int idx) {
-  if (idx > LUA_REGISTRYINDEX) {
-    api_check(L, idx != 0 && -idx <= L->top - L->base);
-    return L->top+idx;
-  }
-  else switch (idx) {  /* pseudo-indices */
-    case LUA_REGISTRYINDEX: return registry(L);
-    case LUA_GLOBALSINDEX: return gt(L);
-    default: {
-      TObject *func = (L->base - 1);
-      idx = LUA_GLOBALSINDEX - idx;
-      lua_assert(iscfunction(func));
-      return (idx <= clvalue(func)->c.nupvalues)
-                ? &clvalue(func)->c.upvalue[idx-1]
-                : NULL;
-    }
-  }
-}
-
-
-static TObject *luaA_index (lua_State *L, int idx) {
-  if (idx > 0) {
-    api_check(L, idx <= L->top - L->base);
-    return L->base + idx - 1;
-  }
-  else {
-    TObject *o = negindex(L, idx);
-    api_check(L, o != NULL);
-    return o;
-  }
-}
-
-
-static TObject *luaA_indexAcceptable (lua_State *L, int idx) {
-  if (idx > 0) {
-    TObject *o = L->base+(idx-1);
-    api_check(L, idx <= L->stack_last - L->base);
-    if (o >= L->top) return NULL;
-    else return o;
-  }
-  else
-    return negindex(L, idx);
-}
-
-
-void luaA_pushobject (lua_State *L, const TObject *o) {
-  setobj2s(L->top, o);
-  incr_top(L);
-}
-
-
-LUA_API int lua_checkstack (lua_State *L, int size) {
-  int res;
-  lua_lock(L);
-  if ((L->top - L->base + size) > LUA_MAXCSTACK)
-    res = 0;  /* stack overflow */
-  else {
-    luaD_checkstack(L, size);
-    if (L->ci->top < L->top + size)
-      L->ci->top = L->top + size;
-    res = 1;
-  }
-  lua_unlock(L);
-  return res;
-}
-
-
-LUA_API void lua_xmove (lua_State *from, lua_State *to, int n) {
-  int i;
-  lua_lock(to);
-  api_checknelems(from, n);
-  from->top -= n;
-  for (i = 0; i < n; i++) {
-    setobj2s(to->top, from->top + i);
-    api_incr_top(to);
-  }
-  lua_unlock(to);
-}
-
-
-LUA_API lua_CFunction lua_atpanic (lua_State *L, lua_CFunction panicf) {
-  lua_CFunction old;
-  lua_lock(L);
-  old = G(L)->panic;
-  G(L)->panic = panicf;
-  lua_unlock(L);
-  return old;
-}
-
-
-LUA_API lua_State *lua_newthread (lua_State *L) {
-  lua_State *L1;
-  lua_lock(L);
-  luaC_checkGC(L);
-  L1 = luaE_newthread(L);
-  setthvalue(L->top, L1);
-  api_incr_top(L);
-  lua_unlock(L);
-  lua_userstateopen(L1);
-  return L1;
-}
-
-
-
-/*
-** basic stack manipulation
-*/
-
-
-LUA_API int lua_gettop (lua_State *L) {
-  return (L->top - L->base);
-}
-
-
-LUA_API void lua_settop (lua_State *L, int idx) {
-  lua_lock(L);
-  if (idx >= 0) {
-    api_check(L, idx <= L->stack_last - L->base);
-    while (L->top < L->base + idx)
-      setnilvalue(L->top++);
-    L->top = L->base + idx;
-  }
-  else {
-    api_check(L, -(idx+1) <= (L->top - L->base));
-    L->top += idx+1;  /* `subtract' index (index is negative) */
-  }
-  lua_unlock(L);
-}
-
-
-LUA_API void lua_remove (lua_State *L, int idx) {
-  StkId p;
-  lua_lock(L);
-  p = luaA_index(L, idx);
-  while (++p < L->top) setobjs2s(p-1, p);
-  L->top--;
-  lua_unlock(L);
-}
-
-
-LUA_API void lua_insert (lua_State *L, int idx) {
-  StkId p;
-  StkId q;
-  lua_lock(L);
-  p = luaA_index(L, idx);
-  for (q = L->top; q>p; q--) setobjs2s(q, q-1);
-  setobjs2s(p, L->top);
-  lua_unlock(L);
-}
-
-
-LUA_API void lua_replace (lua_State *L, int idx) {
-  lua_lock(L);
-  api_checknelems(L, 1);
-  setobj(luaA_index(L, idx), L->top - 1);  /* write barrier */
-  L->top--;
-  lua_unlock(L);
-}
-
-
-LUA_API void lua_pushvalue (lua_State *L, int idx) {
-  lua_lock(L);
-  setobj2s(L->top, luaA_index(L, idx));
-  api_incr_top(L);
-  lua_unlock(L);
-}
-
-
-
-/*
-** access functions (stack -> C)
-*/
-
-
-LUA_API int lua_type (lua_State *L, int idx) {
-  StkId o = luaA_indexAcceptable(L, idx);
-  return (o == NULL) ? LUA_TNONE : ttype(o);
-}
-
-
-LUA_API const char *lua_typename (lua_State *L, int t) {
-  UNUSED(L);
-  return (t == LUA_TNONE) ? "no value" : luaT_typenames[t];
-}
-
-
-LUA_API int lua_iscfunction (lua_State *L, int idx) {
-  StkId o = luaA_indexAcceptable(L, idx);
-  return (o == NULL) ? 0 : iscfunction(o);
-}
-
-
-LUA_API int lua_isnumber (lua_State *L, int idx) {
-  TObject n;
-  const TObject *o = luaA_indexAcceptable(L, idx);
-  return (o != NULL && tonumber(o, &n));
-}
-
-
-LUA_API int lua_isstring (lua_State *L, int idx) {
-  int t = lua_type(L, idx);
-  return (t == LUA_TSTRING || t == LUA_TNUMBER);
-}
-
-
-LUA_API int lua_isuserdata (lua_State *L, int idx) {
-  const TObject *o = luaA_indexAcceptable(L, idx);
-  return (o != NULL && (ttisuserdata(o) || ttislightuserdata(o)));
-}
-
-
-LUA_API int lua_rawequal (lua_State *L, int index1, int index2) {
-  StkId o1 = luaA_indexAcceptable(L, index1);
-  StkId o2 = luaA_indexAcceptable(L, index2);
-  return (o1 == NULL || o2 == NULL) ? 0  /* index out of range */
-                                    : luaO_rawequalObj(o1, o2);
-}
-
-
-LUA_API int lua_equal (lua_State *L, int index1, int index2) {
-  StkId o1, o2;
-  int i;
-  lua_lock(L);  /* may call tag method */
-  o1 = luaA_indexAcceptable(L, index1);
-  o2 = luaA_indexAcceptable(L, index2);
-  i = (o1 == NULL || o2 == NULL) ? 0  /* index out of range */
-                                 : equalobj(L, o1, o2);
-  lua_unlock(L);
-  return i;
-}
-
-
-LUA_API int lua_lessthan (lua_State *L, int index1, int index2) {
-  StkId o1, o2;
-  int i;
-  lua_lock(L);  /* may call tag method */
-  o1 = luaA_indexAcceptable(L, index1);
-  o2 = luaA_indexAcceptable(L, index2);
-  i = (o1 == NULL || o2 == NULL) ? 0  /* index out-of-range */
-                                 : luaV_lessthan(L, o1, o2);
-  lua_unlock(L);
-  return i;
-}
-
-
-
-LUA_API lua_Number lua_tonumber (lua_State *L, int idx) {
-  TObject n;
-  const TObject *o = luaA_indexAcceptable(L, idx);
-  if (o != NULL && tonumber(o, &n))
-    return nvalue(o);
-  else
-    return 0;
-}
-
-
-LUA_API int lua_toboolean (lua_State *L, int idx) {
-  const TObject *o = luaA_indexAcceptable(L, idx);
-  return (o != NULL) && !l_isfalse(o);
-}
-
-
-LUA_API const char *lua_tostring (lua_State *L, int idx) {
-  StkId o = luaA_indexAcceptable(L, idx);
-  if (o == NULL)
-    return NULL;
-  else if (ttisstring(o))
-    return svalue(o);
-  else {
-    const char *s;
-    lua_lock(L);  /* `luaV_tostring' may create a new string */
-    s = (luaV_tostring(L, o) ? svalue(o) : NULL);
-    luaC_checkGC(L);
-    lua_unlock(L);
-    return s;
-  }
-}
-
-
-LUA_API size_t lua_strlen (lua_State *L, int idx) {
-  StkId o = luaA_indexAcceptable(L, idx);
-  if (o == NULL)
-    return 0;
-  else if (ttisstring(o))
-    return tsvalue(o)->tsv.len;
-  else {
-    size_t l;
-    lua_lock(L);  /* `luaV_tostring' may create a new string */
-    l = (luaV_tostring(L, o) ? tsvalue(o)->tsv.len : 0);
-    lua_unlock(L);
-    return l;
-  }
-}
-
-
-LUA_API lua_CFunction lua_tocfunction (lua_State *L, int idx) {
-  StkId o = luaA_indexAcceptable(L, idx);
-  return (o == NULL || !iscfunction(o)) ? NULL : clvalue(o)->c.f;
-}
-
-
-LUA_API void *lua_touserdata (lua_State *L, int idx) {
-  StkId o = luaA_indexAcceptable(L, idx);
-  if (o == NULL) return NULL;
-  switch (ttype(o)) {
-    case LUA_TUSERDATA: return (uvalue(o) + 1);
-    case LUA_TLIGHTUSERDATA: return pvalue(o);
-    default: return NULL;
-  }
-}
-
-
-LUA_API lua_State *lua_tothread (lua_State *L, int idx) {
-  StkId o = luaA_indexAcceptable(L, idx);
-  return (o == NULL || !ttisthread(o)) ? NULL : thvalue(o);
-}
-
-
-LUA_API const void *lua_topointer (lua_State *L, int idx) {
-  StkId o = luaA_indexAcceptable(L, idx);
-  if (o == NULL) return NULL;
-  else {
-    switch (ttype(o)) {
-      case LUA_TTABLE: return hvalue(o);
-      case LUA_TFUNCTION: return clvalue(o);
-      case LUA_TTHREAD: return thvalue(o);
-      case LUA_TUSERDATA:
-      case LUA_TLIGHTUSERDATA:
-        return lua_touserdata(L, idx);
-      default: return NULL;
-    }
-  }
-}
-
-
-
-/*
-** push functions (C -> stack)
-*/
-
-
-LUA_API void lua_pushnil (lua_State *L) {
-  lua_lock(L);
-  setnilvalue(L->top);
-  api_incr_top(L);
-  lua_unlock(L);
-}
-
-
-LUA_API void lua_pushnumber (lua_State *L, lua_Number n) {
-  lua_lock(L);
-  setnvalue(L->top, n);
-  api_incr_top(L);
-  lua_unlock(L);
-}
-
-
-LUA_API void lua_pushlstring (lua_State *L, const char *s, size_t len) {
-  lua_lock(L);
-  luaC_checkGC(L);
-  setsvalue2s(L->top, luaS_newlstr(L, s, len));
-  api_incr_top(L);
-  lua_unlock(L);
-}
-
-
-LUA_API void lua_pushstring (lua_State *L, const char *s) {
-  if (s == NULL)
-    lua_pushnil(L);
-  else
-    lua_pushlstring(L, s, strlen(s));
-}
-
-
-LUA_API const char *lua_pushvfstring (lua_State *L, const char *fmt,
-                                      va_list argp) {
-  const char *ret;
-  lua_lock(L);
-  luaC_checkGC(L);
-  ret = luaO_pushvfstring(L, fmt, argp);
-  lua_unlock(L);
-  return ret;
-}
-
-
-LUA_API const char *lua_pushfstring (lua_State *L, const char *fmt, ...) {
-  const char *ret;
-  va_list argp;
-  lua_lock(L);
-  luaC_checkGC(L);
-  va_start(argp, fmt);
-  ret = luaO_pushvfstring(L, fmt, argp);
-  va_end(argp);
-  lua_unlock(L);
-  return ret;
-}
-
-
-LUA_API void lua_pushcclosure (lua_State *L, lua_CFunction fn, int n) {
-  Closure *cl;
-  lua_lock(L);
-  luaC_checkGC(L);
-  api_checknelems(L, n);
-  cl = luaF_newCclosure(L, n);
-  cl->c.f = fn;
-  L->top -= n;
-  while (n--)
-    setobj2n(&cl->c.upvalue[n], L->top+n);
-  setclvalue(L->top, cl);
-  api_incr_top(L);
-  lua_unlock(L);
-}
-
-
-LUA_API void lua_pushboolean (lua_State *L, int b) {
-  lua_lock(L);
-  setbvalue(L->top, (b != 0));  /* ensure that true is 1 */
-  api_incr_top(L);
-  lua_unlock(L);
-}
-
-
-LUA_API void lua_pushlightuserdata (lua_State *L, void *p) {
-  lua_lock(L);
-  setpvalue(L->top, p);
-  api_incr_top(L);
-  lua_unlock(L);
-}
-
-
-
-/*
-** get functions (Lua -> stack)
-*/
-
-
-LUA_API void lua_gettable (lua_State *L, int idx) {
-  StkId t;
-  lua_lock(L);
-  t = luaA_index(L, idx);
-  setobj2s(L->top - 1, luaV_gettable(L, t, L->top - 1, 0));
-  lua_unlock(L);
-}
-
-
-LUA_API void lua_rawget (lua_State *L, int idx) {
-  StkId t;
-  lua_lock(L);
-  t = luaA_index(L, idx);
-  api_check(L, ttistable(t));
-  setobj2s(L->top - 1, luaH_get(hvalue(t), L->top - 1));
-  lua_unlock(L);
-}
-
-
-LUA_API void lua_rawgeti (lua_State *L, int idx, int n) {
-  StkId o;
-  lua_lock(L);
-  o = luaA_index(L, idx);
-  api_check(L, ttistable(o));
-  setobj2s(L->top, luaH_getnum(hvalue(o), n));
-  api_incr_top(L);
-  lua_unlock(L);
-}
-
-
-LUA_API void lua_newtable (lua_State *L) {
-  lua_lock(L);
-  luaC_checkGC(L);
-  sethvalue(L->top, luaH_new(L, 0, 0));
-  api_incr_top(L);
-  lua_unlock(L);
-}
-
-
-LUA_API int lua_getmetatable (lua_State *L, int objindex) {
-  const TObject *obj;
-  Table *mt = NULL;
-  int res;
-  lua_lock(L);
-  obj = luaA_indexAcceptable(L, objindex);
-  if (obj != NULL) {
-    switch (ttype(obj)) {
-      case LUA_TTABLE:
-        mt = hvalue(obj)->metatable;
-        break;
-      case LUA_TUSERDATA:
-        mt = uvalue(obj)->uv.metatable;
-        break;
-    }
-  }
-  if (mt == NULL || mt == hvalue(defaultmeta(L)))
-    res = 0;
-  else {
-    sethvalue(L->top, mt);
-    api_incr_top(L);
-    res = 1;
-  }
-  lua_unlock(L);
-  return res;
-}
-
-
-LUA_API void lua_getfenv (lua_State *L, int idx) {
-  StkId o;
-  lua_lock(L);
-  o = luaA_index(L, idx);
-  setobj2s(L->top, isLfunction(o) ? &clvalue(o)->l.g : gt(L));
-  api_incr_top(L);
-  lua_unlock(L);
-}
-
-
-/*
-** set functions (stack -> Lua)
-*/
-
-
-LUA_API void lua_settable (lua_State *L, int idx) {
-  StkId t;
-  lua_lock(L);
-  api_checknelems(L, 2);
-  t = luaA_index(L, idx);
-  luaV_settable(L, t, L->top - 2, L->top - 1);
-  L->top -= 2;  /* pop index and value */
-  lua_unlock(L);
-}
-
-
-LUA_API void lua_rawset (lua_State *L, int idx) {
-  StkId t;
-  lua_lock(L);
-  api_checknelems(L, 2);
-  t = luaA_index(L, idx);
-  api_check(L, ttistable(t));
-  setobj2t(luaH_set(L, hvalue(t), L->top-2), L->top-1);  /* write barrier */
-  L->top -= 2;
-  lua_unlock(L);
-}
-
-
-LUA_API void lua_rawseti (lua_State *L, int idx, int n) {
-  StkId o;
-  lua_lock(L);
-  api_checknelems(L, 1);
-  o = luaA_index(L, idx);
-  api_check(L, ttistable(o));
-  setobj2t(luaH_setnum(L, hvalue(o), n), L->top-1);  /* write barrier */
-  L->top--;
-  lua_unlock(L);
-}
-
-
-LUA_API int lua_setmetatable (lua_State *L, int objindex) {
-  TObject *obj, *mt;
-  int res = 1;
-  lua_lock(L);
-  api_checknelems(L, 1);
-  obj = luaA_index(L, objindex);
-  mt = (!ttisnil(L->top - 1)) ? L->top - 1 : defaultmeta(L);
-  api_check(L, ttistable(mt));
-  switch (ttype(obj)) {
-    case LUA_TTABLE: {
-      hvalue(obj)->metatable = hvalue(mt);  /* write barrier */
-      break;
-    }
-    case LUA_TUSERDATA: {
-      uvalue(obj)->uv.metatable = hvalue(mt);  /* write barrier */
-      break;
-    }
-    default: {
-      res = 0;  /* cannot set */
-      break;
-    }
-  }
-  L->top--;
-  lua_unlock(L);
-  return res;
-}
-
-
-LUA_API int lua_setfenv (lua_State *L, int idx) {
-  StkId o;
-  int res = 0;
-  lua_lock(L);
-  api_checknelems(L, 1);
-  o = luaA_index(L, idx);
-  L->top--;
-  api_check(L, ttistable(L->top));
-  if (isLfunction(o)) {
-    res = 1;
-    clvalue(o)->l.g = *(L->top);
-  }
-  lua_unlock(L);
-  return res;
-}
-
-
-/*
-** `load' and `call' functions (run Lua code)
-*/
-
-LUA_API void lua_call (lua_State *L, int nargs, int nresults) {
-  StkId func;
-  lua_lock(L);
-  api_checknelems(L, nargs+1);
-  func = L->top - (nargs+1);
-  luaD_call(L, func, nresults);
-  lua_unlock(L);
-}
-
-
-
-/*
-** Execute a protected call.
-*/
-struct CallS {  /* data to `f_call' */
-  StkId func;
-  int nresults;
-};
-
-
-static void f_call (lua_State *L, void *ud) {
-  struct CallS *c = cast(struct CallS *, ud);
-  luaD_call(L, c->func, c->nresults);
-}
-
-
-
-LUA_API int lua_pcall (lua_State *L, int nargs, int nresults, int errfunc) {
-  struct CallS c;
-  int status;
-  ptrdiff_t func;
-  lua_lock(L);
-  func = (errfunc == 0) ? 0 : savestack(L, luaA_index(L, errfunc));
-  c.func = L->top - (nargs+1);  /* function to be called */
-  c.nresults = nresults;
-  status = luaD_pcall(L, f_call, &c, savestack(L, c.func), func);
-  lua_unlock(L);
-  return status;
-}
-
-
-/*
-** Execute a protected C call.
-*/
-struct CCallS {  /* data to `f_Ccall' */
-  lua_CFunction func;
-  void *ud;
-};
-
-
-static void f_Ccall (lua_State *L, void *ud) {
-  struct CCallS *c = cast(struct CCallS *, ud);
-  Closure *cl;
-  cl = luaF_newCclosure(L, 0);
-  cl->c.f = c->func;
-  setclvalue(L->top, cl);  /* push function */
-  incr_top(L);
-  setpvalue(L->top, c->ud);  /* push only argument */
-  incr_top(L);
-  luaD_call(L, L->top - 2, 0);
-}
-
-
-LUA_API int lua_cpcall (lua_State *L, lua_CFunction func, void *ud) {
-  struct CCallS c;
-  int status;
-  lua_lock(L);
-  c.func = func;
-  c.ud = ud;
-  status = luaD_pcall(L, f_Ccall, &c, savestack(L, L->top), 0);
-  lua_unlock(L);
-  return status;
-}
-
-
-LUA_API int lua_load (lua_State *L, lua_Chunkreader reader, void *data,
-                      const char *chunkname) {
-  ZIO z;
-  int status;
-  int c;
-  lua_lock(L);
-  if (!chunkname) chunkname = "?";
-  luaZ_init(&z, reader, data, chunkname);
-  c = luaZ_lookahead(&z);
-  status = luaD_protectedparser(L, &z, (c == LUA_SIGNATURE[0]));
-  lua_unlock(L);
-  return status;
-}
-
-
-LUA_API int lua_dump (lua_State *L, lua_Chunkwriter writer, void *data) {
-  int status;
-  TObject *o;
-  lua_lock(L);
-  api_checknelems(L, 1);
-  o = L->top - 1;
-  if (isLfunction(o) && clvalue(o)->l.nupvalues == 0) {
-    luaU_dump(L, clvalue(o)->l.p, writer, data);
-    status = 1;
-  }
-  else
-    status = 0;
-  lua_unlock(L);
-  return status;
-}
-
-
-/*
-** Garbage-collection functions
-*/
-
-/* GC values are expressed in Kbytes: #bytes/2^10 */
-#define GCscalel(x)		((x)>>10)
-#define GCscale(x)		(cast(int, GCscalel(x)))
-#define GCunscale(x)		(cast(lu_mem, x)<<10)
-
-LUA_API int lua_getgcthreshold (lua_State *L) {
-  int threshold;
-  lua_lock(L);
-  threshold = GCscale(G(L)->GCthreshold);
-  lua_unlock(L);
-  return threshold;
-}
-
-LUA_API int lua_getgccount (lua_State *L) {
-  int count;
-  lua_lock(L);
-  count = GCscale(G(L)->nblocks);
-  lua_unlock(L);
-  return count;
-}
-
-LUA_API void lua_setgcthreshold (lua_State *L, int newthreshold) {
-  lua_lock(L);
-  if (cast(lu_mem, newthreshold) > GCscalel(MAX_LUMEM))
-    G(L)->GCthreshold = MAX_LUMEM;
-  else
-    G(L)->GCthreshold = GCunscale(newthreshold);
-  luaC_checkGC(L);
-  lua_unlock(L);
-}
-
-
-/*
-** miscellaneous functions
-*/
-
-
-LUA_API const char *lua_version (void) {
-  return LUA_VERSION;
-}
-
-
-LUA_API int lua_error (lua_State *L) {
-  lua_lock(L);
-  api_checknelems(L, 1);
-  luaG_errormsg(L);
-  lua_unlock(L);
-  return 0;  /* to avoid warnings */
-}
-
-
-LUA_API int lua_next (lua_State *L, int idx) {
-  StkId t;
-  int more;
-  lua_lock(L);
-  t = luaA_index(L, idx);
-  api_check(L, ttistable(t));
-  more = luaH_next(L, hvalue(t), L->top - 1);
-  if (more) {
-    api_incr_top(L);
-  }
-  else  /* no more elements */
-    L->top -= 1;  /* remove key */
-  lua_unlock(L);
-  return more;
-}
-
-
-LUA_API void lua_concat (lua_State *L, int n) {
-  lua_lock(L);
-  luaC_checkGC(L);
-  api_checknelems(L, n);
-  if (n >= 2) {
-    luaV_concat(L, n, L->top - L->base - 1);
-    L->top -= (n-1);
-  }
-  else if (n == 0) {  /* push empty string */
-    setsvalue2s(L->top, luaS_newlstr(L, NULL, 0));
-    api_incr_top(L);
-  }
-  /* else n == 1; nothing to do */
-  lua_unlock(L);
-}
-
-
-LUA_API void *lua_newuserdata (lua_State *L, size_t size) {
-  Udata *u;
-  lua_lock(L);
-  luaC_checkGC(L);
-  u = luaS_newudata(L, size);
-  setuvalue(L->top, u);
-  api_incr_top(L);
-  lua_unlock(L);
-  return u + 1;
-}
-
-
-LUA_API int lua_pushupvalues (lua_State *L) {
-  Closure *func;
-  int n, i;
-  lua_lock(L);
-  api_check(L, iscfunction(L->base - 1));
-  func = clvalue(L->base - 1);
-  n = func->c.nupvalues;
-  luaD_checkstack(L, n + LUA_MINSTACK);
-  for (i=0; i<n; i++) {
-    setobj2s(L->top, &func->c.upvalue[i]);
-    L->top++;
-  }
-  lua_unlock(L);
-  return n;
-}
-
-
-static const char *aux_upvalue (lua_State *L, int funcindex, int n,
-                                TObject **val) {
-  Closure *f;
-  StkId fi = luaA_index(L, funcindex);
-  if (!ttisfunction(fi)) return NULL;
-  f = clvalue(fi);
-  if (f->c.isC) {
-    if (n > f->c.nupvalues) return NULL;
-    *val = &f->c.upvalue[n-1];
-    return "";
-  }
-  else {
-    Proto *p = f->l.p;
-    if (n > p->sizeupvalues) return NULL;
-    *val = f->l.upvals[n-1]->v;
-    return getstr(p->upvalues[n-1]);
-  }
-}
-
-
-LUA_API const char *lua_getupvalue (lua_State *L, int funcindex, int n) {
-  const char *name;
-  TObject *val;
-  lua_lock(L);
-  name = aux_upvalue(L, funcindex, n, &val);
-  if (name) {
-    setobj2s(L->top, val);
-    api_incr_top(L);
-  }
-  lua_unlock(L);
-  return name;
-}
-
-
-LUA_API const char *lua_setupvalue (lua_State *L, int funcindex, int n) {
-  const char *name;
-  TObject *val;
-  lua_lock(L);
-  api_checknelems(L, 1);
-  name = aux_upvalue(L, funcindex, n, &val);
-  if (name) {
-    L->top--;
-    setobj(val, L->top);  /* write barrier */
-  }
-  lua_unlock(L);
-  return name;
-}
-
+/*
+** $Id: lapi.c,v 1.4 2004-11-27 21:46:07 pixel Exp $
+** Lua API
+** See Copyright Notice in lua.h
+*/
+
+
+#include <assert.h>
+#include <string.h>
+
+#define lapi_c
+
+#include "lua.h"
+
+#include "lapi.h"
+#include "ldebug.h"
+#include "ldo.h"
+#include "lfunc.h"
+#include "lgc.h"
+#include "lmem.h"
+#include "lobject.h"
+#include "lstate.h"
+#include "lstring.h"
+#include "ltable.h"
+#include "ltm.h"
+#include "lundump.h"
+#include "lvm.h"
+
+
+const char lua_ident[] =
+  "$Lua: " LUA_VERSION " " LUA_COPYRIGHT " $\n"
+  "$Authors: " LUA_AUTHORS " $\n"
+  "$URL: www.lua.org $\n";
+
+
+
+#ifndef api_check
+#define api_check(L, o)		/*{ assert(o); }*/
+#endif
+
+#define api_checknelems(L, n)	api_check(L, (n) <= (L->top - L->base))
+
+#define api_incr_top(L)   {api_check(L, L->top < L->ci->top); L->top++;}
+
+
+
+
+static TObject *negindex (lua_State *L, int idx) {
+  if (idx > LUA_REGISTRYINDEX) {
+    api_check(L, idx != 0 && -idx <= L->top - L->base);
+    return L->top+idx;
+  }
+  else switch (idx) {  /* pseudo-indices */
+    case LUA_REGISTRYINDEX: return registry(L);
+    case LUA_GLOBALSINDEX: return gt(L);
+    default: {
+      TObject *func = (L->base - 1);
+      idx = LUA_GLOBALSINDEX - idx;
+      lua_assert(iscfunction(func));
+      return (idx <= clvalue(func)->c.nupvalues)
+                ? &clvalue(func)->c.upvalue[idx-1]
+                : NULL;
+    }
+  }
+}
+
+
+static TObject *luaA_index (lua_State *L, int idx) {
+  if (idx > 0) {
+    api_check(L, idx <= L->top - L->base);
+    return L->base + idx - 1;
+  }
+  else {
+    TObject *o = negindex(L, idx);
+    api_check(L, o != NULL);
+    return o;
+  }
+}
+
+
+static TObject *luaA_indexAcceptable (lua_State *L, int idx) {
+  if (idx > 0) {
+    TObject *o = L->base+(idx-1);
+    api_check(L, idx <= L->stack_last - L->base);
+    if (o >= L->top) return NULL;
+    else return o;
+  }
+  else
+    return negindex(L, idx);
+}
+
+
+void luaA_pushobject (lua_State *L, const TObject *o) {
+  setobj2s(L->top, o);
+  incr_top(L);
+}
+
+
+LUA_API int lua_checkstack (lua_State *L, int size) {
+  int res;
+  lua_lock(L);
+  if ((L->top - L->base + size) > LUA_MAXCSTACK)
+    res = 0;  /* stack overflow */
+  else {
+    luaD_checkstack(L, size);
+    if (L->ci->top < L->top + size)
+      L->ci->top = L->top + size;
+    res = 1;
+  }
+  lua_unlock(L);
+  return res;
+}
+
+
+LUA_API void lua_xmove (lua_State *from, lua_State *to, int n) {
+  int i;
+  lua_lock(to);
+  api_checknelems(from, n);
+  from->top -= n;
+  for (i = 0; i < n; i++) {
+    setobj2s(to->top, from->top + i);
+    api_incr_top(to);
+  }
+  lua_unlock(to);
+}
+
+
+LUA_API lua_CFunction lua_atpanic (lua_State *L, lua_CFunction panicf) {
+  lua_CFunction old;
+  lua_lock(L);
+  old = G(L)->panic;
+  G(L)->panic = panicf;
+  lua_unlock(L);
+  return old;
+}
+
+
+LUA_API lua_State *lua_newthread (lua_State *L) {
+  lua_State *L1;
+  lua_lock(L);
+  luaC_checkGC(L);
+  L1 = luaE_newthread(L);
+  setthvalue(L->top, L1);
+  api_incr_top(L);
+  lua_unlock(L);
+  lua_userstateopen(L1);
+  return L1;
+}
+
+
+
+/*
+** basic stack manipulation
+*/
+
+
+LUA_API int lua_gettop (lua_State *L) {
+  return (L->top - L->base);
+}
+
+
+LUA_API void lua_settop (lua_State *L, int idx) {
+  lua_lock(L);
+  if (idx >= 0) {
+    api_check(L, idx <= L->stack_last - L->base);
+    while (L->top < L->base + idx)
+      setnilvalue(L->top++);
+    L->top = L->base + idx;
+  }
+  else {
+    api_check(L, -(idx+1) <= (L->top - L->base));
+    L->top += idx+1;  /* `subtract' index (index is negative) */
+  }
+  lua_unlock(L);
+}
+
+
+LUA_API void lua_remove (lua_State *L, int idx) {
+  StkId p;
+  lua_lock(L);
+  p = luaA_index(L, idx);
+  while (++p < L->top) setobjs2s(p-1, p);
+  L->top--;
+  lua_unlock(L);
+}
+
+
+LUA_API void lua_insert (lua_State *L, int idx) {
+  StkId p;
+  StkId q;
+  lua_lock(L);
+  p = luaA_index(L, idx);
+  for (q = L->top; q>p; q--) setobjs2s(q, q-1);
+  setobjs2s(p, L->top);
+  lua_unlock(L);
+}
+
+
+LUA_API void lua_replace (lua_State *L, int idx) {
+  lua_lock(L);
+  api_checknelems(L, 1);
+  setobj(luaA_index(L, idx), L->top - 1);  /* write barrier */
+  L->top--;
+  lua_unlock(L);
+}
+
+
+LUA_API void lua_pushvalue (lua_State *L, int idx) {
+  lua_lock(L);
+  setobj2s(L->top, luaA_index(L, idx));
+  api_incr_top(L);
+  lua_unlock(L);
+}
+
+
+
+/*
+** access functions (stack -> C)
+*/
+
+
+LUA_API int lua_type (lua_State *L, int idx) {
+  StkId o = luaA_indexAcceptable(L, idx);
+  return (o == NULL) ? LUA_TNONE : ttype(o);
+}
+
+
+LUA_API const char *lua_typename (lua_State *L, int t) {
+  UNUSED(L);
+  return (t == LUA_TNONE) ? "no value" : luaT_typenames[t];
+}
+
+
+LUA_API int lua_iscfunction (lua_State *L, int idx) {
+  StkId o = luaA_indexAcceptable(L, idx);
+  return (o == NULL) ? 0 : iscfunction(o);
+}
+
+
+LUA_API int lua_isnumber (lua_State *L, int idx) {
+  TObject n;
+  const TObject *o = luaA_indexAcceptable(L, idx);
+  return (o != NULL && tonumber(o, &n));
+}
+
+
+LUA_API int lua_isstring (lua_State *L, int idx) {
+  int t = lua_type(L, idx);
+  return (t == LUA_TSTRING || t == LUA_TNUMBER);
+}
+
+
+LUA_API int lua_isuserdata (lua_State *L, int idx) {
+  const TObject *o = luaA_indexAcceptable(L, idx);
+  return (o != NULL && (ttisuserdata(o) || ttislightuserdata(o)));
+}
+
+
+LUA_API int lua_rawequal (lua_State *L, int index1, int index2) {
+  StkId o1 = luaA_indexAcceptable(L, index1);
+  StkId o2 = luaA_indexAcceptable(L, index2);
+  return (o1 == NULL || o2 == NULL) ? 0  /* index out of range */
+                                    : luaO_rawequalObj(o1, o2);
+}
+
+
+LUA_API int lua_equal (lua_State *L, int index1, int index2) {
+  StkId o1, o2;
+  int i;
+  lua_lock(L);  /* may call tag method */
+  o1 = luaA_indexAcceptable(L, index1);
+  o2 = luaA_indexAcceptable(L, index2);
+  i = (o1 == NULL || o2 == NULL) ? 0  /* index out of range */
+                                 : equalobj(L, o1, o2);
+  lua_unlock(L);
+  return i;
+}
+
+
+LUA_API int lua_lessthan (lua_State *L, int index1, int index2) {
+  StkId o1, o2;
+  int i;
+  lua_lock(L);  /* may call tag method */
+  o1 = luaA_indexAcceptable(L, index1);
+  o2 = luaA_indexAcceptable(L, index2);
+  i = (o1 == NULL || o2 == NULL) ? 0  /* index out-of-range */
+                                 : luaV_lessthan(L, o1, o2);
+  lua_unlock(L);
+  return i;
+}
+
+
+
+LUA_API lua_Number lua_tonumber (lua_State *L, int idx) {
+  TObject n;
+  const TObject *o = luaA_indexAcceptable(L, idx);
+  if (o != NULL && tonumber(o, &n))
+    return nvalue(o);
+  else
+    return 0;
+}
+
+
+LUA_API int lua_toboolean (lua_State *L, int idx) {
+  const TObject *o = luaA_indexAcceptable(L, idx);
+  return (o != NULL) && !l_isfalse(o);
+}
+
+
+LUA_API const char *lua_tostring (lua_State *L, int idx) {
+  StkId o = luaA_indexAcceptable(L, idx);
+  if (o == NULL)
+    return NULL;
+  else if (ttisstring(o))
+    return svalue(o);
+  else {
+    const char *s;
+    lua_lock(L);  /* `luaV_tostring' may create a new string */
+    s = (luaV_tostring(L, o) ? svalue(o) : NULL);
+    luaC_checkGC(L);
+    lua_unlock(L);
+    return s;
+  }
+}
+
+
+LUA_API size_t lua_strlen (lua_State *L, int idx) {
+  StkId o = luaA_indexAcceptable(L, idx);
+  if (o == NULL)
+    return 0;
+  else if (ttisstring(o))
+    return tsvalue(o)->tsv.len;
+  else {
+    size_t l;
+    lua_lock(L);  /* `luaV_tostring' may create a new string */
+    l = (luaV_tostring(L, o) ? tsvalue(o)->tsv.len : 0);
+    lua_unlock(L);
+    return l;
+  }
+}
+
+
+LUA_API lua_CFunction lua_tocfunction (lua_State *L, int idx) {
+  StkId o = luaA_indexAcceptable(L, idx);
+  return (o == NULL || !iscfunction(o)) ? NULL : clvalue(o)->c.f;
+}
+
+
+LUA_API void *lua_touserdata (lua_State *L, int idx) {
+  StkId o = luaA_indexAcceptable(L, idx);
+  if (o == NULL) return NULL;
+  switch (ttype(o)) {
+    case LUA_TUSERDATA: return (uvalue(o) + 1);
+    case LUA_TLIGHTUSERDATA: return pvalue(o);
+    default: return NULL;
+  }
+}
+
+
+LUA_API lua_State *lua_tothread (lua_State *L, int idx) {
+  StkId o = luaA_indexAcceptable(L, idx);
+  return (o == NULL || !ttisthread(o)) ? NULL : thvalue(o);
+}
+
+
+LUA_API const void *lua_topointer (lua_State *L, int idx) {
+  StkId o = luaA_indexAcceptable(L, idx);
+  if (o == NULL) return NULL;
+  else {
+    switch (ttype(o)) {
+      case LUA_TTABLE: return hvalue(o);
+      case LUA_TFUNCTION: return clvalue(o);
+      case LUA_TTHREAD: return thvalue(o);
+      case LUA_TUSERDATA:
+      case LUA_TLIGHTUSERDATA:
+        return lua_touserdata(L, idx);
+      default: return NULL;
+    }
+  }
+}
+
+
+
+/*
+** push functions (C -> stack)
+*/
+
+
+LUA_API void lua_pushnil (lua_State *L) {
+  lua_lock(L);
+  setnilvalue(L->top);
+  api_incr_top(L);
+  lua_unlock(L);
+}
+
+
+LUA_API void lua_pushnumber (lua_State *L, lua_Number n) {
+  lua_lock(L);
+  setnvalue(L->top, n);
+  api_incr_top(L);
+  lua_unlock(L);
+}
+
+
+LUA_API void lua_pushlstring (lua_State *L, const char *s, size_t len) {
+  lua_lock(L);
+  luaC_checkGC(L);
+  setsvalue2s(L->top, luaS_newlstr(L, s, len));
+  api_incr_top(L);
+  lua_unlock(L);
+}
+
+
+LUA_API void lua_pushstring (lua_State *L, const char *s) {
+  if (s == NULL)
+    lua_pushnil(L);
+  else
+    lua_pushlstring(L, s, strlen(s));
+}
+
+
+LUA_API const char *lua_pushvfstring (lua_State *L, const char *fmt,
+                                      va_list argp) {
+  const char *ret;
+  lua_lock(L);
+  luaC_checkGC(L);
+  ret = luaO_pushvfstring(L, fmt, argp);
+  lua_unlock(L);
+  return ret;
+}
+
+
+LUA_API const char *lua_pushfstring (lua_State *L, const char *fmt, ...) {
+  const char *ret;
+  va_list argp;
+  lua_lock(L);
+  luaC_checkGC(L);
+  va_start(argp, fmt);
+  ret = luaO_pushvfstring(L, fmt, argp);
+  va_end(argp);
+  lua_unlock(L);
+  return ret;
+}
+
+
+LUA_API void lua_pushcclosure (lua_State *L, lua_CFunction fn, int n) {
+  Closure *cl;
+  lua_lock(L);
+  luaC_checkGC(L);
+  api_checknelems(L, n);
+  cl = luaF_newCclosure(L, n);
+  cl->c.f = fn;
+  L->top -= n;
+  while (n--)
+    setobj2n(&cl->c.upvalue[n], L->top+n);
+  setclvalue(L->top, cl);
+  api_incr_top(L);
+  lua_unlock(L);
+}
+
+
+LUA_API void lua_pushboolean (lua_State *L, int b) {
+  lua_lock(L);
+  setbvalue(L->top, (b != 0));  /* ensure that true is 1 */
+  api_incr_top(L);
+  lua_unlock(L);
+}
+
+
+LUA_API void lua_pushlightuserdata (lua_State *L, void *p) {
+  lua_lock(L);
+  setpvalue(L->top, p);
+  api_incr_top(L);
+  lua_unlock(L);
+}
+
+
+
+/*
+** get functions (Lua -> stack)
+*/
+
+
+LUA_API void lua_gettable (lua_State *L, int idx) {
+  StkId t;
+  lua_lock(L);
+  t = luaA_index(L, idx);
+  setobj2s(L->top - 1, luaV_gettable(L, t, L->top - 1, 0));
+  lua_unlock(L);
+}
+
+
+LUA_API void lua_rawget (lua_State *L, int idx) {
+  StkId t;
+  lua_lock(L);
+  t = luaA_index(L, idx);
+  api_check(L, ttistable(t));
+  setobj2s(L->top - 1, luaH_get(hvalue(t), L->top - 1));
+  lua_unlock(L);
+}
+
+
+LUA_API void lua_rawgeti (lua_State *L, int idx, int n) {
+  StkId o;
+  lua_lock(L);
+  o = luaA_index(L, idx);
+  api_check(L, ttistable(o));
+  setobj2s(L->top, luaH_getnum(hvalue(o), n));
+  api_incr_top(L);
+  lua_unlock(L);
+}
+
+
+LUA_API void lua_newtable (lua_State *L) {
+  lua_lock(L);
+  luaC_checkGC(L);
+  sethvalue(L->top, luaH_new(L, 0, 0));
+  api_incr_top(L);
+  lua_unlock(L);
+}
+
+
+LUA_API int lua_getmetatable (lua_State *L, int objindex) {
+  const TObject *obj;
+  Table *mt = NULL;
+  int res;
+  lua_lock(L);
+  obj = luaA_indexAcceptable(L, objindex);
+  if (obj != NULL) {
+    switch (ttype(obj)) {
+      case LUA_TTABLE:
+        mt = hvalue(obj)->metatable;
+        break;
+      case LUA_TUSERDATA:
+        mt = uvalue(obj)->uv.metatable;
+        break;
+    }
+  }
+  if (mt == NULL || mt == hvalue(defaultmeta(L)))
+    res = 0;
+  else {
+    sethvalue(L->top, mt);
+    api_incr_top(L);
+    res = 1;
+  }
+  lua_unlock(L);
+  return res;
+}
+
+
+LUA_API void lua_getfenv (lua_State *L, int idx) {
+  StkId o;
+  lua_lock(L);
+  o = luaA_index(L, idx);
+  setobj2s(L->top, isLfunction(o) ? &clvalue(o)->l.g : gt(L));
+  api_incr_top(L);
+  lua_unlock(L);
+}
+
+
+/*
+** set functions (stack -> Lua)
+*/
+
+
+LUA_API void lua_settable (lua_State *L, int idx) {
+  StkId t;
+  lua_lock(L);
+  api_checknelems(L, 2);
+  t = luaA_index(L, idx);
+  luaV_settable(L, t, L->top - 2, L->top - 1);
+  L->top -= 2;  /* pop index and value */
+  lua_unlock(L);
+}
+
+
+LUA_API void lua_rawset (lua_State *L, int idx) {
+  StkId t;
+  lua_lock(L);
+  api_checknelems(L, 2);
+  t = luaA_index(L, idx);
+  api_check(L, ttistable(t));
+  setobj2t(luaH_set(L, hvalue(t), L->top-2), L->top-1);  /* write barrier */
+  L->top -= 2;
+  lua_unlock(L);
+}
+
+
+LUA_API void lua_rawseti (lua_State *L, int idx, int n) {
+  StkId o;
+  lua_lock(L);
+  api_checknelems(L, 1);
+  o = luaA_index(L, idx);
+  api_check(L, ttistable(o));
+  setobj2t(luaH_setnum(L, hvalue(o), n), L->top-1);  /* write barrier */
+  L->top--;
+  lua_unlock(L);
+}
+
+
+LUA_API int lua_setmetatable (lua_State *L, int objindex) {
+  TObject *obj, *mt;
+  int res = 1;
+  lua_lock(L);
+  api_checknelems(L, 1);
+  obj = luaA_index(L, objindex);
+  mt = (!ttisnil(L->top - 1)) ? L->top - 1 : defaultmeta(L);
+  api_check(L, ttistable(mt));
+  switch (ttype(obj)) {
+    case LUA_TTABLE: {
+      hvalue(obj)->metatable = hvalue(mt);  /* write barrier */
+      break;
+    }
+    case LUA_TUSERDATA: {
+      uvalue(obj)->uv.metatable = hvalue(mt);  /* write barrier */
+      break;
+    }
+    default: {
+      res = 0;  /* cannot set */
+      break;
+    }
+  }
+  L->top--;
+  lua_unlock(L);
+  return res;
+}
+
+
+LUA_API int lua_setfenv (lua_State *L, int idx) {
+  StkId o;
+  int res = 0;
+  lua_lock(L);
+  api_checknelems(L, 1);
+  o = luaA_index(L, idx);
+  L->top--;
+  api_check(L, ttistable(L->top));
+  if (isLfunction(o)) {
+    res = 1;
+    clvalue(o)->l.g = *(L->top);
+  }
+  lua_unlock(L);
+  return res;
+}
+
+
+/*
+** `load' and `call' functions (run Lua code)
+*/
+
+LUA_API void lua_call (lua_State *L, int nargs, int nresults) {
+  StkId func;
+  lua_lock(L);
+  api_checknelems(L, nargs+1);
+  func = L->top - (nargs+1);
+  luaD_call(L, func, nresults);
+  lua_unlock(L);
+}
+
+
+
+/*
+** Execute a protected call.
+*/
+struct CallS {  /* data to `f_call' */
+  StkId func;
+  int nresults;
+};
+
+
+static void f_call (lua_State *L, void *ud) {
+  struct CallS *c = cast(struct CallS *, ud);
+  luaD_call(L, c->func, c->nresults);
+}
+
+
+
+LUA_API int lua_pcall (lua_State *L, int nargs, int nresults, int errfunc) {
+  struct CallS c;
+  int status;
+  ptrdiff_t func;
+  lua_lock(L);
+  func = (errfunc == 0) ? 0 : savestack(L, luaA_index(L, errfunc));
+  c.func = L->top - (nargs+1);  /* function to be called */
+  c.nresults = nresults;
+  status = luaD_pcall(L, f_call, &c, savestack(L, c.func), func);
+  lua_unlock(L);
+  return status;
+}
+
+
+/*
+** Execute a protected C call.
+*/
+struct CCallS {  /* data to `f_Ccall' */
+  lua_CFunction func;
+  void *ud;
+};
+
+
+static void f_Ccall (lua_State *L, void *ud) {
+  struct CCallS *c = cast(struct CCallS *, ud);
+  Closure *cl;
+  cl = luaF_newCclosure(L, 0);
+  cl->c.f = c->func;
+  setclvalue(L->top, cl);  /* push function */
+  incr_top(L);
+  setpvalue(L->top, c->ud);  /* push only argument */
+  incr_top(L);
+  luaD_call(L, L->top - 2, 0);
+}
+
+
+LUA_API int lua_cpcall (lua_State *L, lua_CFunction func, void *ud) {
+  struct CCallS c;
+  int status;
+  lua_lock(L);
+  c.func = func;
+  c.ud = ud;
+  status = luaD_pcall(L, f_Ccall, &c, savestack(L, L->top), 0);
+  lua_unlock(L);
+  return status;
+}
+
+
+LUA_API int lua_load (lua_State *L, lua_Chunkreader reader, void *data,
+                      const char *chunkname) {
+  ZIO z;
+  int status;
+  int c;
+  lua_lock(L);
+  if (!chunkname) chunkname = "?";
+  luaZ_init(&z, reader, data, chunkname);
+  c = luaZ_lookahead(&z);
+  status = luaD_protectedparser(L, &z, (c == LUA_SIGNATURE[0]));
+  lua_unlock(L);
+  return status;
+}
+
+
+LUA_API int lua_dump (lua_State *L, lua_Chunkwriter writer, void *data) {
+  int status;
+  TObject *o;
+  lua_lock(L);
+  api_checknelems(L, 1);
+  o = L->top - 1;
+  if (isLfunction(o) && clvalue(o)->l.nupvalues == 0) {
+    luaU_dump(L, clvalue(o)->l.p, writer, data);
+    status = 1;
+  }
+  else
+    status = 0;
+  lua_unlock(L);
+  return status;
+}
+
+
+/*
+** Garbage-collection functions
+*/
+
+/* GC values are expressed in Kbytes: #bytes/2^10 */
+#define GCscalel(x)		((x)>>10)
+#define GCscale(x)		(cast(int, GCscalel(x)))
+#define GCunscale(x)		(cast(lu_mem, x)<<10)
+
+LUA_API int lua_getgcthreshold (lua_State *L) {
+  int threshold;
+  lua_lock(L);
+  threshold = GCscale(G(L)->GCthreshold);
+  lua_unlock(L);
+  return threshold;
+}
+
+LUA_API int lua_getgccount (lua_State *L) {
+  int count;
+  lua_lock(L);
+  count = GCscale(G(L)->nblocks);
+  lua_unlock(L);
+  return count;
+}
+
+LUA_API void lua_setgcthreshold (lua_State *L, int newthreshold) {
+  lua_lock(L);
+  if (cast(lu_mem, newthreshold) > GCscalel(MAX_LUMEM))
+    G(L)->GCthreshold = MAX_LUMEM;
+  else
+    G(L)->GCthreshold = GCunscale(newthreshold);
+  luaC_checkGC(L);
+  lua_unlock(L);
+}
+
+
+/*
+** miscellaneous functions
+*/
+
+
+LUA_API const char *lua_version (void) {
+  return LUA_VERSION;
+}
+
+
+LUA_API int lua_error (lua_State *L) {
+  lua_lock(L);
+  api_checknelems(L, 1);
+  luaG_errormsg(L);
+  lua_unlock(L);
+  return 0;  /* to avoid warnings */
+}
+
+
+LUA_API int lua_next (lua_State *L, int idx) {
+  StkId t;
+  int more;
+  lua_lock(L);
+  t = luaA_index(L, idx);
+  api_check(L, ttistable(t));
+  more = luaH_next(L, hvalue(t), L->top - 1);
+  if (more) {
+    api_incr_top(L);
+  }
+  else  /* no more elements */
+    L->top -= 1;  /* remove key */
+  lua_unlock(L);
+  return more;
+}
+
+
+LUA_API void lua_concat (lua_State *L, int n) {
+  lua_lock(L);
+  luaC_checkGC(L);
+  api_checknelems(L, n);
+  if (n >= 2) {
+    luaV_concat(L, n, L->top - L->base - 1);
+    L->top -= (n-1);
+  }
+  else if (n == 0) {  /* push empty string */
+    setsvalue2s(L->top, luaS_newlstr(L, NULL, 0));
+    api_incr_top(L);
+  }
+  /* else n == 1; nothing to do */
+  lua_unlock(L);
+}
+
+
+LUA_API void *lua_newuserdata (lua_State *L, size_t size) {
+  Udata *u;
+  lua_lock(L);
+  luaC_checkGC(L);
+  u = luaS_newudata(L, size);
+  setuvalue(L->top, u);
+  api_incr_top(L);
+  lua_unlock(L);
+  return u + 1;
+}
+
+
+LUA_API int lua_pushupvalues (lua_State *L) {
+  Closure *func;
+  int n, i;
+  lua_lock(L);
+  api_check(L, iscfunction(L->base - 1));
+  func = clvalue(L->base - 1);
+  n = func->c.nupvalues;
+  luaD_checkstack(L, n + LUA_MINSTACK);
+  for (i=0; i<n; i++) {
+    setobj2s(L->top, &func->c.upvalue[i]);
+    L->top++;
+  }
+  lua_unlock(L);
+  return n;
+}
+
+
+static const char *aux_upvalue (lua_State *L, int funcindex, int n,
+                                TObject **val) {
+  Closure *f;
+  StkId fi = luaA_index(L, funcindex);
+  if (!ttisfunction(fi)) return NULL;
+  f = clvalue(fi);
+  if (f->c.isC) {
+    if (n > f->c.nupvalues) return NULL;
+    *val = &f->c.upvalue[n-1];
+    return "";
+  }
+  else {
+    Proto *p = f->l.p;
+    if (n > p->sizeupvalues) return NULL;
+    *val = f->l.upvals[n-1]->v;
+    return getstr(p->upvalues[n-1]);
+  }
+}
+
+
+LUA_API const char *lua_getupvalue (lua_State *L, int funcindex, int n) {
+  const char *name;
+  TObject *val;
+  lua_lock(L);
+  name = aux_upvalue(L, funcindex, n, &val);
+  if (name) {
+    setobj2s(L->top, val);
+    api_incr_top(L);
+  }
+  lua_unlock(L);
+  return name;
+}
+
+
+LUA_API const char *lua_setupvalue (lua_State *L, int funcindex, int n) {
+  const char *name;
+  TObject *val;
+  lua_lock(L);
+  api_checknelems(L, 1);
+  name = aux_upvalue(L, funcindex, n, &val);
+  if (name) {
+    L->top--;
+    setobj(val, L->top);  /* write barrier */
+  }
+  lua_unlock(L);
+  return name;
+}
+