Function lua_tolstring

Source/Misc/lua/src/lua.c:2192–2207

LUA_API const char *lua_tolstring (lua_State *L, int idx, size_t *len) {
StkId o = index2adr(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 = index2adr(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_objlen (lua_State *L, int idx) {