[Dovecot] Slightly more intelligent way of handling issues in sdbox?

[Mark Zealey]

Hi there,

I was doing some testing on sdbox yesterday. Basically I did the 
following procedure:

1) Create new sdbox; deliver 2 messages into it (u.1, u.2)
2) Create a copy of the index file (no cache file created yet)
3) deliver another message to the mailbox (u.3)
4) copy back index file from stage (2)
5) deliver new mail

Then the message delivered in stage 3 ie u.3 gets replaced with the 
message delivered in (5) also called u.3. Is it possible to try an 
open/access call on the mail file before overwriting it with the new 
message in case we have an issue where an older version of the index 
file is present (eg due to nfs latencies) ? I notice when you are 
expunging files you very carefully open them and read the header 
contents to make sure the guid is the same as in the index - any reason 
that this is not done when delivering? This is with lmtp on dovecot 2.0.16.

I also noticed that index corruption in sdbox does not get automatically 
repaired. I know this is because the flags are stored in the index files 
so you'd get some loss of flags, but in many situations for us this 
auto-repair with flag loss would be better than having the mailbox 
locked out until we manually do a force-resync on it. (speaking of 
which, it would be great if force-resync also rebuilt the cache files if 
there are valid cache files around, rather than just doing away with them)

Thanks,

Mark