[Dovecot] Apple patch 10

[Mike Abbott]

> Also I thought that your patch would only put the same user's
> connections to the same process.

Our aim was high scalability so we had to mix users on processes.  We  
are aware of the security implications.

I could see a trinary state for this:  "off" for the current behavior,  
"safe" for the behavior you describe, and "max" for the behavior in  
this patch.

> Maybe just SIGUSR2 that's available everywhere?

Sure.  We chose SIGINFO because libraries on some systems hijack  
SIGUSR[12] for their own purposes and we didn't want to step on any  
toes.

>> - The logging tag for a persistent mail process is just "*" instead  
>> of
>> the user name
> Couldn't this also be done the same way as environment switching?

No because the master process adds the tag, not the mail process.

> mail-processes.c:mail_connections
> should probably be an array instead of a hash table.

Sure, either way.  The hash table affords quick lookups when  
mail_max_connections is large, but scanning an array for an int is  
fast too.