Subject: Re: [PATCH v4 4/5] merge: close the index lock when not writing the new index

From: Junio C Hamano <[email-masked]>
Date: Tue, 13 Jun 2017 12:47:30 -0700

Joel Teichroeb <[email-masked]> writes:

> If the merge does not have anything to do, it does not unlock the index,
> causing any further index operations to fail. Thus, always unlock the index
> regardless of outcome.
>
> Signed-off-by: Joel Teichroeb <[email-masked]>
> ---

This one makes sense.  

So far, nobody who calls this function performs further index
manipulations and letting the atexit handlers automatically release
the lock was sufficient.  This allows new callers to do more work on
the index after a merge finishes.

>  merge-recursive.c | 9 ++++++---
>  1 file changed, 6 insertions(+), 3 deletions(-)
>
> diff --git a/merge-recursive.c b/merge-recursive.c
> index ae5238d82c..16bb5512ef 100644
> --- a/merge-recursive.c
> +++ b/merge-recursive.c
> @@ -2145,9 +2145,12 @@ int merge_recursive_generic(struct merge_options *o,
>  	if (clean < 0)
>  		return clean;
>  
> -	if (active_cache_changed &&
> -	    write_locked_index(&the_index, lock, COMMIT_LOCK))
> -		return err(o, _("Unable to write index."));
> +	if (active_cache_changed) {
> +		if (write_locked_index(&the_index, lock, COMMIT_LOCK))
> +			return err(o, _("Unable to write index."));
> +	} else {
> +		rollback_lock_file(lock);
> +	}
>  
>  	return clean ? 0 : 1;
>  }