Function lua_tolstring

third-party/lua-5.2.4/src/lapi.c:389–404

LUA_API const char *lua_tolstring (lua_State *L, int idx, size_t *len) {
  StkId o = index2addr(L, idx);
  if (!ttisstring(o)) {
    lua_lock(L);  /* `luaV_tostring' may create a new string */
    if (!luaV_tostring(L, o)) {  /* conversion failed? */
      if (len != NULL) *len = 0;
      lua_unlock(L);
      return NULL;
    }
    luaC_checkGC(L);
    o = index2addr(L, idx);  /* previous call may reallocate the stack */
    lua_unlock(L);
  }
  if (len != NULL) *len = tsvalue(o)->len;
  return svalue(o);
}


LUA_API size_t lua_rawlen (lua_State *L, int idx) {