[OpenSIPS-Devel] [OpenSIPS/opensips] d34e1f: Fix broken ldap async engine

[ionutrazvanionita]

  Branch: refs/heads/master
  Home:   https://github.com/OpenSIPS/opensips
  Commit: d34e1fe59aaa6fb9adbb7e4d1cb58efb7b68023d
      https://github.com/OpenSIPS/opensips/commit/d34e1fe59aaa6fb9adbb7e4d1cb58efb7b68023d
  Author: ionutrazvanionita <ionutionita at opensips.org>
  Date:   2016-10-19 (Wed, 19 Oct 2016)

  Changed paths:
    M modules/ldap/README
    M modules/ldap/doc/ldap_admin.xml
    M modules/ldap/ld_session.c
    M modules/ldap/ld_session.h
    M modules/ldap/ldap_api_fn.c
    M modules/ldap/ldap_api_fn.h
    M modules/ldap/ldap_connect.c
    M modules/ldap/ldap_connect.h
    M modules/ldap/ldap_exp_fn.c
    M modules/ldap/ldap_exp_fn.h
    M modules/ldap/ldap_mod.c

  Log Message:
  -----------
  Fix broken ldap async engine

   Previous ldap async engine implementation was broken. Now the
module stores a pool of connections for each session which will
be used for executing async queries and one separate connection
that will be used for synchronous queries, in case the maximum number
of open connections allowed(max_async_connections module parameter)
is reached. The sync connection will also be used for synchronous
queries from other functions.
   The connection pool is stored per process, so each worker
process will have its own pool and synchronous connection. For large
numbers of asynchronous ldap calls per second, having a higher value
for max_async_connections will result in better performance.