Re: [Tarantool-patches] [PATCH v3 1/2] b-tree: return NULL on matras_alloc fail

[Vladislav Shpilevoy <v.shpilevoy@tarantool.org>]

Hi! Thanks for the patch!

I agree with Nikita in everything, especially
about bps_tree_create_inner().

Sorry, when I said that code style should be
fixed I didn't take into account that bps_tree
is like a separate library with own code style
where ! is used instead of == NULL.

On 20/01/2020 19:13, Ilya Kosarev wrote:
> In bps_tree_create_leaf we use matras_alloc in case
> bps_tree_garbage_pop didn't work out. However it also might not
> succeed. Then we need to return NULL instead of dereferencing NULL
> pointer.
> 
> Part of #3807
> ---
>  src/lib/salad/bps_tree.h | 7 +++++--
>  1 file changed, 5 insertions(+), 2 deletions(-)
> 
> diff --git a/src/lib/salad/bps_tree.h b/src/lib/salad/bps_tree.h
> index d28b53f53..a10f0a32c 100644
> --- a/src/lib/salad/bps_tree.h
> +++ b/src/lib/salad/bps_tree.h
> @@ -2147,8 +2147,11 @@ bps_tree_create_leaf(struct bps_tree *tree, bps_tree_block_id_t *id)
>  {
>  	struct bps_leaf *res = (struct bps_leaf *)
>  			       bps_tree_garbage_pop(tree, id);
> -	if (!res)
> -		res = (struct bps_leaf *)matras_alloc(&tree->matras, id);
> +	if (res == NULL) {
> +		res = (struct bps_leaf *) matras_alloc(&tree->matras, id);
> +		if (res == NULL)
> +			return NULL;
> +	}
>  	res->header.type = BPS_TREE_BT_LEAF;
>  	tree->leaf_count++;
>  	return res;
>