Function luaL_findtable

Source/Misc/lua/src/lua.c:10569–10593

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 = strchr(fname, '.');
if (e == NULL) e = fname + strlen(fname);
lua_pushlstring(L, fname, e - fname);
lua_rawget(L, -2);
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)) {  /* 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;
}