LUALIB_API const char *luaL_findtable (lua_State *L, int idx,
const char *fname, int szhint) {
const char *e;
lua_pushvalue(L, idx);
do {
e = c_strchr(fname, '.');
if (e == NULL) e = fname + c_strlen(fname);
lua_pushlstring(L, fname, e - fname);
lua_rawget(L, -2);
if (lua_isnil(L, -1)) {
/* If looking for a global variable, check the rotables too */
void *ptable = luaR_findglobal(fname, e - fname);
if (ptable) {
lua_pop(L, 1);
lua_pushrotable(L, ptable);
}
}
if (lua_isnil(L, -1)) { /* no such field? */
lua_pop(L, 1); /* remove this nil */
lua_createtable(L, 0, (*e == '.' ? 1 : szhint)); /* new table for field */
lua_pushlstring(L, fname, e - fname);
lua_pushvalue(L, -2);
lua_settable(L, -4); /* set new table into field */
}
else if (!lua_istable(L, -1) && !lua_isrotable(L, -1)) { /* field has a non-table value? */
lua_pop(L, 2); /* remove table and value */
return fname; /* return problematic part of the name */
}
lua_remove(L, -2); /* remove previous table */
fname = e + 1;
} while (*e == '.');
return NULL;
}
LUALIB_API int luaL_rometatable (lua_State *L, const char* tname, void *p) {
lua_getfield(L, LUA_REGISTRYINDEX, tname); /* get registry.name */
if (!lua_isnil(L, -1)) /* name already in use? */
return 0; /* leave previous value on top, but return 0 */
lua_pop(L, 1);
lua_pushrotable(L, p);
lua_pushvalue(L, -1);
lua_setfield(L, LUA_REGISTRYINDEX, tname); /* registry.name = metatable */
return 1;
}
static int ll_require (lua_State *L) {
const char *name = luaL_checkstring(L, 1);
int i;
lua_settop(L, 1); /* _LOADED table will be at index 2 */
lua_getfield(L, LUA_REGISTRYINDEX, "_LOADED");
lua_getfield(L, 2, name);
if (lua_toboolean(L, -1)) { /* is it there? */
if (lua_touserdata(L, -1) == sentinel) /* check loops */
luaL_error(L, "loop or previous error loading module " LUA_QS, name);
return 1; /* package is already loaded */
}
/* Is this a readonly table? */
{
void *res = luaR_findglobal(name, strlen(name));
if (res) {
lua_pushrotable(L, res);
return 1;
}
}
/* else must load it; iterate over available loaders */
lua_getfield(L, LUA_ENVIRONINDEX, "loaders");
if (!lua_istable(L, -1))
luaL_error(L, LUA_QL("package.loaders") " must be a table");
lua_pushliteral(L, ""); /* error message accumulator */
for (i = 1; ; i++) {
lua_rawgeti(L, -2, i); /* get a loader */
if (lua_isnil(L, -1))
luaL_error(L, "module " LUA_QS " not found:%s",
name, lua_tostring(L, -2));
lua_pushstring(L, name);
lua_call(L, 1, 1); /* call it */
if (lua_isfunction(L, -1)) /* did it find module? */
break; /* module loaded successfully */
else if (lua_isstring(L, -1)) /* loader returned error message? */
lua_concat(L, 2); /* accumulate it */
else
lua_pop(L, 1);
}
lua_pushlightuserdata(L, sentinel);
lua_setfield(L, 2, name); /* _LOADED[name] = sentinel */
lua_pushstring(L, name); /* pass name as argument to module */
lua_call(L, 1, 1); /* run loaded module */
if (!lua_isnil(L, -1)) /* non-nil return? */
lua_setfield(L, 2, name); /* _LOADED[name] = returned value */
lua_getfield(L, 2, name);
if (lua_touserdata(L, -1) == sentinel) { /* module did not set a value? */
lua_pushboolean(L, 1); /* use true as result */
lua_pushvalue(L, -1); /* extra copy to be returned */
lua_setfield(L, 2, name); /* _LOADED[name] = true */
}
return 1;
}
/*
** Open string library
*/
LUALIB_API int luaopen_string (lua_State *L) {
#if LUA_OPTIMIZE_MEMORY == 0
luaL_register(L, LUA_STRLIBNAME, strlib);
#if defined(LUA_COMPAT_GFIND)
lua_getfield(L, -1, "gmatch");
lua_setfield(L, -2, "gfind");
#endif
createmetatable(L);
return 1;
#else
lua_pushliteral(L,"");
lua_pushrotable(L, (void*)strlib);
lua_setmetatable(L, -2);
lua_pop(L,1);
return 0;
#endif
}
static int luaB_index(lua_State *L) {
#if LUA_OPTIMIZE_MEMORY == 2
int fres;
if ((fres = luaR_findfunction(L, base_funcs_list)) != 0)
return fres;
#endif
const char *keyname = luaL_checkstring(L, 2);
if (!c_strcmp(keyname, "_VERSION")) {
lua_pushliteral(L, LUA_VERSION);
return 1;
}
void *res = luaR_findglobal(keyname, c_strlen(keyname));
if (!res)
return 0;
else {
lua_pushrotable(L, res);
return 1;
}
}