[sheepdog] [PATCH 2/2] collie: add a check&repair command

[MORITA Kazutaka]

At Wed, 20 Jun 2012 18:16:02 +0800,
Liu Yuan wrote:
> +
> +static void do_check_repair(uint64_t oid, int nr_copies)
> +{
> +	struct sd_vnode *tgt_vnodes[nr_copies];
> +	unsigned char sha1[nr_copies][SHA1_LEN];
> +	void *buf;
> +	int i;
> +
> +	collie_oid_to_vnodes(vnode_list_entries, nr_vnodes,
> +			     oid, nr_copies, tgt_vnodes);
> +	for (i = 0; i < nr_copies; i++) {
> +		buf = read_object_from(tgt_vnodes[i], oid);
> +		SHA1(buf, SD_DATA_OBJ_SIZE, sha1[i]);

memcmp against contents of the object directly looks simpler than
calculating their hash values.


> +		free(buf);
> +	}
> +
> +	if (!memcmp(sha1[0], sha1[1], SHA1_LEN) &&
> +	    !memcmp(sha1[0], sha1[2], SHA1_LEN))
> +		return; /* All replica consistent */

This will fail if the number of replica is not three.

Kazutaka