Re: How to pass arguments to argv function effectively in Lua C API

[Ricardo Ramos Massaro <ricardo.massaro@...>]

\On Thu, Mar 24, 2011 at 7:44 PM, Alexander Gladysh <agladysh@gmail.com> wrote:
> On Fri, Mar 25, 2011 at 01:35, Peter Cawley <lua@corsix.org> wrote:
>> On Thu, Mar 24, 2011 at 10:28 PM, Daurnimator <quae@daurnimator.com> wrote:
>>> Is there something wrong with
>>>        int params = lua_gettop(L);
>>>        char **argv = malloc(params);
>>>        int i;
>>>        for (i=1;i<=params;i++) {
>>>                argv[i-1]=luaL_checkstring(L,i);
>>>        }
>
>> Yes:
>> 1. The call to malloc may fail and return NULL, thus causing invalid
>> memory access on "argv[i-1]".
>> 2. The calls to luaL_checkstring may throw errors, thus leaking the
>> memory allocated for "argv".
>
> 3. It bypasses allocator that Lua state uses.

4. It passes the wrong size to malloc(), it should be "params*sizeof(char*)"

- Ricardo