[E-devel] Re: Ecore_Dlist_Append bug.

[Nathan I. <nin...@gm...>]

Thanks, patch applied to CVS.

On 7/21/05, Dylan Shell <ds...@ro...> wrote:
> Currently ecore_dlist_append has a bug in that it increments the
> list->nodes without considering whether it makes a previously invalid
> list->index valid. If this happens, the list has a valid index, and thus
> interprets the list->current member as pointing to node data.
>=20
> Here is code that shows the invalid behavior in the current implementatio=
n:
>=20
> =3D=3D=3D=3D=3D BEGIN CODE SNIPPET =3D=3D=3D=3D=3D
>=20
> #include <Ecore.h>
> #include <Ecore_Data.h>
> #include <string.h>
> #include <stdlib.h>
>=20
> void print_list(Ecore_DList *list)
> {
>     char *item;
>=20
>     /* Seek to end by looking for NULL */
>     ecore_dlist_goto_first(list);
>     while ((item =3D (char *)ecore_dlist_next(list)) !=3D NULL)
>     {
>         printf("%p %s\n", item, item);
>     }
>=20
>     printf("\n");
> }
>=20
> int main(int argc, const char **argv)
> {
>     char *first =3D "first";
>     char *second =3D "second";
>     char *p;
>     int i, nn;
>=20
>     Ecore_DList *list;
>=20
>     list =3D ecore_dlist_new();
>     ecore_dlist_append(list, first);
>=20
>     print_list(list);
>=20
>     ecore_dlist_append(list, second);
>=20
>     /* Now try another way: */
>=20
>     nn =3D ecore_dlist_nodes(list);
>     for (i =3D 0;i < nn;i++)
>     {
>         p =3D ecore_dlist_goto_index(list, i);
>         printf("%d %p %s\n",i, p, p);
>=20
>     }
>=20
>=20
>=20
>     return EXIT_SUCCESS;
> }
>=20
> =3D=3D=3D=3D=3D END CODE SNIPPET =3D=3D=3D=3D=3D
>=20
>=20
> One would expect the "goto_index" print list to print the list, instead
> it prints the first element twice.
> Below is the patch to CVS head that fixes this.
>=20
> =3D=3D=3D=3D=3D BEGIN PATCH =3D=3D=3D=3D=3D
>=20
> RCS file: /cvsroot/enlightenment/e17/libs/ecore/src/lib/ecore/ecore_list.=
c,v
> retrieving revision 1.15
> diff -p -u -r1.15 ecore_list.c
> --- ecore_list.c    30 Jun 2005 16:47:29 -0000    1.15
> +++ ecore_list.c    21 Jul 2005 18:22:30 -0000
> @@ -372,6 +372,12 @@ static int _ecore_list_append_0(Ecore_Li
>          list->current =3D NULL;
>      }
>=20
> +    if (list->index >=3D list->nodes) /* Index was out of bounds, ensure
> that we don't make it "in bounds"
> +                                       but with an invalid current
> pointer by incrementing the nodes */
> +        list->index++;
> +
> +
> +
>      list->nodes++;
>=20
>      return TRUE;
>=20
> =3D=3D=3D=3D=3D END PATCH =3D=3D=3D=3D=3D
>=20
> Dylan.
>=20
>=20
>