Re: [Tarantool-patches] [PATCH v2 1/2] b-tree: return NULL on matras_alloc fail

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

Hi! Thanks for the patch!

On 13/01/2020 22:31, 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

Please, drop ':', we don't use it when reference tickets.

> ---
>  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..ede2a3b7f 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) {
> +		res = (struct bps_leaf *) matras_alloc(&tree->matras, id);
> +		if (!res)
> +			return NULL;
> +	}

Since you've changed this code anyway, lets use explicit
'== NULL' instead of '!'.