Re: Exception handling!!!

[Philip Guenther <guenther+ldapsoft@sendmail.com>]

On Mon, 26 Apr 2010, Pratima Shet wrote:
> Ya, application is multi threaded, but only one thread will handle all 
> ldap related operations.

The crypto library that you're using may place its own requirements.  In 
particular, many versions of openssl are only thread-safe if various 
callbacks are set before performing operations concurrently in multiple 
threads.  You may have only one thread doing ldap related operations 
(including ldap_start_tls_s()), but perhaps other threads could be doing 
crypto or TLS/SSL operations for other tasks or protocols?


> I am linking to "libldap" not "libldap_r".

My recall is that libldap_r will set up those openssl thread-safety 
callbacks for you while libldap won't.

(That's actually a reason in some cases to *not* use libldap_r, as an 
application may have reasons for initializing those before initializing 
libldap* or independently of doing so.)


> Crash happened only once. Am unabled to reproduce it. So, I dont have 
> much information regarding the line in the library where it crashed 
> exactly.

Yeah, debugging intermittent issues and race-conditions can be (very) 
frustrating.


> Handle was not NULL, but it was corrupted.

Or the SSL handle inside the LDAP handle was corrupt, or some other static 
state was corrupt, or...


> Is there any way, to check whether ldap handle is proper or valid apart 
> from NULL check ?

In general, no.


Philip Guenther