[PATCH v1 2/2] oci: replace layer index with layer digest

[Gao Xiang]

Hi Chengyu,

On 2025/9/13 16:27, ChengyuZhu6 wrote:
> From: Chengyu Zhu <hudsonzhu at tencent.com>
> 
> Replace numeric layer_index with layer_digest string for more precise
> and reliable OCI layer identification. This change affects both mkfs.erofs
> and mount.erofs tools.
> 
> Signed-off-by: Chengyu Zhu <hudsonzhu at tencent.com>

Could we have a way to support both layer index and digest?

For users using `mkfs.erofs` or `mount.erofs` directly, I think
they feel more convenient to use layer index instead.

But for snapshotter and failover cases, I think layer digest is
more suitable.

Thanks,
Gao Xiang