[PATCH] Fix for database locking crashes (was Re: bogofilter/bogoutil concurrency crash?)

[David Relson]

At 12:30 AM 4/7/03, Jim Correia wrote:

>On Monday, April 7, 2003, at 01:12  AM, David Relson wrote:
>
>>The sequence "db_close(handle,??); handle = NULL; goto open_err" is 
>>inefficient.  open_err: calls dbh_free(handle) and returns NULL.  As you 
>>point out, the call to dbh_free() is not needed because db_close() has 
>>already called dbh_free().  The code after the call to db_close() should 
>>be "return NULL" (which is simpler).
>
>Fair enough. (In my own code I usually have centralized cleanup and a 
>single return at the bottom of the function. In this case I was trying to 
>adhere to the existing code style, but I can see how yours is a better fit.)
>
>>Also, you added a "goto open_error".  That exits the "waiting for the 
>>lock" loop, which is _not_ what we want.
>
>Thanks for catching this. (In my editor indent and tab are both set at 4 
>so the entire for block was flush with the brace, and my bug was masked by 
>the caller also looping on the lock failure.)
>
>>The attached patch has the critical "handle = NULL" and added test for 
>>handle != NULL before using it.  Give it a try and let me know how well 
>>it works (compared to your patch).
>
>make check still passes and the bug is likewise corrected.
>
>Thanks,
>Jim

Jim,

Glad to get the positive report.  The code changes have been committed to 
CVS and a new bogofilter will be built today and put on SourceForge.

David