Re: error restoring Unix socket ... path too long to be stored properly

On 02/05/2021 20:01, imschmeg wrote:
> I am getting this error during extraction of an archive of an encrypted
> file system (each file and its filename are encrypted separately,
> that's why the long jibberish filenames). The source and destination are
> the same f2fs file system on Debian stable 10.9.  The original socket
> name works, so why can't dar extract that same name?  Is this a problem
> specific to sockets?  Is it a problem with dar's understanding of the
> f2fs filesystem?  There are many other much longer pathnames in
> this backup that were extracted without issue, but this was the only
> socket.

this messages is issued by dar because the filename exceed the system
constant UNIX_PATH_MAX defined by your operating system.

The problem here is portability, not all system define such constant and
when it is not defined, libdar uses a somehow very restrictive value
that was known to work for every system.

Now I realize that this par of the code is old and things around unix
sockets may have changed. I will see how to get something more flexible
without taking the risk to break portability (not all operating systems
have the same limitations).

> 
> Also note the second error - after dar shortens the socket name to 1y,
> it ignores that when trying to set the access/mod time and instead uses
> the original longer name.

You are right. It should not restore the socket at all and trigger an
error. Trunking that was is not a good solution, I will have a look at
that too, thanks for feedback.

> 
> The extraction is via dar_static_2.16.4_x86_64_GNU_Linux.
> 
> error restoring Unix socket
> /test/extracted/tstuser/.cipher/pIfxiZMpaxuzJh30lp04iA/_gpq3AzCwhKLUb23hVclGg/mnHz8gVk8IYxO1x9oqlDDQ/1yPGRcfpLKIgzWjS526c9g,
> path too long to be stored properly, socket will be created as
> /test/extracted/tstuser/.cipher/pIfxiZMpaxuzJh30lp04iA/_gpq3AzCwhKLUb23hVclGg/mnHz8gVk8IYxO1x9oqlDDQ/1y
> instead, do you confirm? [return = YES | Esc = NO] Continuing... Error
> while restoring
> /test/extracted/tstuser/.cipher/pIfxiZMpaxuzJh30lp04iA/_gpq3AzCwhKLUb23hVclGg/mnHz8gVk8IYxO1x9oqlDDQ/1yPGRcfpLKIgzWjS526c9g
> : Cannot set last access and last modification time: No such file or
> directory
> 
> Everything but that socket cheks out:
> # diff -qr --no-dereference .cipher /home/tstuser/.cipher
> Only in
> .cipher/pIfxiZMpaxuzJh30lp04iA/_gpq3AzCwhKLUb23hVclGg/mnHz8gVk8IYxO1x9oqlDDQ:
> 1y Only in
> /home/tstuser/.cipher/pIfxiZMpaxuzJh30lp04iA/_gpq3AzCwhKLUb23hVclGg/mnHz8gVk8IYxO1x9oqlDDQ:
> 1yPGRcfpLKIgzWjS526c9g
> 
>