[Dovecot] Bug with partial IMAP fetches

[Matthew Reimer]

Timo Sirainen wrote:

> On Tuesday, Nov 4, 2003, at 21:10 Europe/Helsinki, Matthew Reimer wrote:
>
>> I think I've found the bug. The attached patch fixes the problem for 
>> me. The first problem is that the wrong value is being returned by 
>> message_send() because ret is getting set to the wrong value (see 
>> above or patch). The second problem is that in the special case where 
>> physical_size == virtual_size (i.e., sendfile can be used) 
>> i_stream_skip(input, virtual_skip) is being called on the input 
>> stream. This is wrong because virtual_skip is supposed to indicate 
>> that \r was the last character seen and therefore \n needs to be sent 
>> before any of the input stream; but in the sendfile case this is not 
>> necessary.
>>
>> I think a little refactoring of seek_partial(), message_send() and 
>> message_skip_virtual() might be helpful to clarify the code. The 
>> virtual_skip argument to message_send() is an off_t but is only used 
>> to indicate that \r was the last character read, so it would probably 
>> be more clear to add another argument cr_skipped (like 
>> message_skip_virtual()). Better might be to put all the partial cache 
>> stuff in message-send.c.
>
>
> It actually was supposed to be skip byte count, not just CR-indicator. 
> But you're right, it was used wrong in sendfile code path. There was 
> one piece of code anymore which used the virtual_skip more than just 
> for CR (BODY[HEADER]<..>) and it was easy to change. I think the 
> attached patch should fix it properly.

I tested 0.99.10.2 and it works fine. Thanks!

Matt