Possible improvements for casync extract statistics

[elboulangero]

While playing with casync, I needed additional statistics for the extract verb. I patched my way to the following output (differences introduced by my patches are in bold).

casync extract --seed-output=no --seed /dev/sda5 --store ${URL:?}/${IMAGE:?}.castr ${URL:?}/${IMAGE:?}.caibx /dev/sda6
Zero bytes written as sparse files: 0B
Bytes cloned through reflinks: 0B
Chunk requests fulfilled from local store: 0 (0%)
Bytes used from local store: 0B (0%)
Chunk requests fulfilled from local seed: 53030 (63%)
Bytes used from local seed: 3.5G (58%)
Chunk requests fulfilled from remote store: 30720 (36%)
Bytes used from remote store: 2.4G (41%)
Bytes downloaded from remote store: 833.0M
Time spent seeding: 86 secs (13%)
Time spent extracting: 554 secs (86%)
Total time spent for operation: 640 secs (00:10:40)

Are you interested in any of these changes? If so I can rework and share this patcheset for review. Thx.

[elfgoh]

I am interested!

[poettering]

@elboulangero yes, such a patch would definitely be welcome!