To support incremental backups (where not all chunks are sent to the
server), a new parameter "reuse-csum" is introduced on the
"create_fixed_index" API call. When set and equal to last backups'
checksum, the backup writer clones the data from the last index of this
archive file, and only updates chunks it actually receives.
In incremental mode some checks usually done on closing an index cannot
be made, since they would be inaccurate.
Signed-off-by: Stefan Reiter <s.reiter@proxmox.com>
if *only* data chunks are registered (high chance during incremental
backup), then chunk_count might be one lower then upload_stat.count
because of the zero chunk being unconditionally uploaded but not used.
Thus when subtracting the two, an overflow would occur.
In general, don't let the client make the server panic, instead just set
duplicates to 0.
Signed-off-by: Stefan Reiter <s.reiter@proxmox.com>
Stefan ReiterandDietmar Maurer