Re: Questions about binary deltas and an internal error

On 14/03/2023 16:22, Denis Corbin wrote:
> 
> 
> On 14/03/2023 03:16, John Goerzen wrote:
>> Hi Denis,
>>
>> Thank you for looking into it!  I have one question:
>>
> [...]
>>
>> I'm not sure if this is at all practical for my use case, but does this
>> imply that if somehow I transport an isolated catalogue along with the
>> backup, dar -x -A would do the right thing in sequential read mode?
> 
> Yes, this works, I could restore a full and differential backup having a 
> delta patch:
> 
> dar -x - --sequential-read -A isolated_catalogue ... < backup.1.dar

Well, I was wrong: it does not work in all cases, in particular when you 
use filters (not extracting all files). I've fixed this bug.

The problem of extracting  in sequential read mode a backup containing 
binary patch is also fixed.

I have still some tests to complete but you can test these fixes using 
the release candidate 1 for version 2.7.9 (2.7.9.RC1) available at:

https://dar.edrusb.org/dar.linux.free.fr/Interim_releases/

or from github and sourceforge repositories.

> 
> This explains by the fact that once the catalog is loaded into memory 
> (from isolated_catalogue.1.dar file) the base CRC are known and 
> sequentially reading the backup to be restore, starts knowing the 
> information that was missing else.
> 
>>
>> - John
>>
> 
> Cheers,
> Denis
>