lapi.cpp

这个是symbian下的一个蛮庞大的3D游戏源代码！对于学习3D开发的人有很大的帮助！

  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 = 0;
  int res;
  lua_lock(L);
  obj = luaA_indexAcceptable(L, objindex);
  if (obj != 0) {
    switch (ttype(obj)) {
      case LUA_TTABLE:
        mt = hvalue(obj)->metatable;
        break;
      case LUA_TUSERDATA:
        mt = uvalue(obj)->uv.metatable;
        break;
    }
  }
  if (mt == 0 || 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, 0, 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 0;
  f = clvalue(fi);
  if (f->c.isC) {
    if (n > f->c.nupvalues) return 0;
    *val = &f->c.upvalue[n-1];
    return "";
  }
  else {
    Proto *p = f->l.p;
    if (n > p->sizeupvalues) return 0;
    *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;
}