Re: [PATCH 37/38] refs: make lock generic

From: Junio C Hamano <gitster@pobox.com>
Date: Jun 7, 2016, 17:50 UTC
Message-ID: <xmqqlh2griq3.fsf@gitster.mtv.corp.google.com>
In-Reply-To: <d2a3cb56d7276c00174a08fe609d63e00755b205.1464983301.git.mhagger@alum.mit.edu>

Michael Haggerty <mhagger@alum.mit.edu> writes:

Show 5 quoted lines

> From: David Turner <dturner@twopensource.com>
>
> Instead of including a files-backend-specific struct ref_lock, change
> the generic ref_update struct to include a void pointer that backends
> can use for their own arbitrary data.

Hmph.

Show 15 quoted lines

> @@ -3591,7 +3590,8 @@ static int lock_ref_for_update(struct files_ref_store *refs,
>  		for (parent_update = update->parent_update;
>  		     parent_update;
>  		     parent_update = parent_update->parent_update) {
> -			oidcpy(&parent_update->lock->old_oid, &lock->old_oid);
> +			struct ref_lock *parent_lock = parent_update->backend_data;
> +			oidcpy(&parent_lock->old_oid, &lock->old_oid);
>  		}
> ...
> @@ -3745,7 +3745,7 @@ static int files_transaction_commit(struct ref_store *ref_store,
>  	/* Perform updates first so live commits remain referenced */
>  	for (i = 0; i < transaction->nr; i++) {
>  		struct ref_update *update = updates[i];
> -		struct ref_lock *lock = update->lock;
> +		struct ref_lock *lock = update->backend_data;

OK, and files_* backend method downcasts it to what it wants, which is good.