[sheepdog] [PATCH v5 6/6] zookeeper: handle session timeout for all zookeeper operations

[MORITA Kazutaka]

At Thu, 20 Jun 2013 12:00:22 -0700,
Kai Zhang wrote:
> 
> @@ -365,19 +397,12 @@ static void zk_queue_pop_advance(struct zk_event *ev)
>  	len = sizeof(*ev);
>  	snprintf(path, sizeof(path), QUEUE_ZNODE "/%010"PRId32, queue_pos);
>  	rc = zk_get_data(path, ev, &len);
> -	if (rc != ZOK)
> -		panic("failed to get data from %s, %s", path, zerror(rc));
> -	sd_dprintf("%s, type:%d, len:%d, pos:%"PRId32, path, ev->type, len,
> -		   queue_pos);
> -	queue_pos++;
> -}
> -
> -static int zk_member_empty(void)
> -{
> -	struct String_vector strs;
> -
> -	zk_get_children(MEMBER_ZNODE, &strs);
> -	return (strs.count == 0);
> +	if (rc == ZOK) {
> +		sd_dprintf("%s, type:%d, len:%d, pos:%"PRId32, path, ev->type,
> +			   len, queue_pos);
> +		queue_pos++;
> +	} else
> +		sd_eprintf("failed, path %s, %s", path, zerror(rc));
>  }

With this change, this function can return without setting ev.
However, the caller zk_event_handler() access the zk_event
unconditionally.

> @@ -568,15 +611,17 @@ static void zk_get_least_seq(const char *parent, char *least_seq_path,
>  
>  		if (rc == ZOK) {
>  			strncpy(least_seq_path, path, path_len);
> -			break;
> +			return ZOK;
>  		} else if (rc == ZNONODE)
>  			continue;
> -		else
> -			panic("failed, path:%s, %s", path, zerror(rc));
> +		else {
> +			sd_eprintf("failed, %s", zerror(rc));
> +			return rc;

Same here.  This function can return without setting least_seq_path,
but zk_find_master() doesn't check the return value of this function.

Thanks,

Kazutaka