New logging

[Gary Williams <Gary.Williams@sas.com>]

Kurt and others,

I have pushed the new logging routines, and, I think, enough
usage in the slapd modules to show how it's used, and what the
mechanism is.  Basically, it allows levels to be set on a per
subsystem basis, rather than just on or off for a particular
subsystem.  To turn on the new logging routines, #define
NEW_LOGGING 1, and rebuild everything.  I took the easy way out
and pretty much just duplicated the existing debug statements,
but if the new logging is acceptable, I think it opens the door
for much more informative and useful logging by the server, and
more control by the administrator.  Below are new configuration
file directives that control the logging levels for the various
subsystems.  For what the levels are intended to mean, take a look
at ldap_log.h, hopefully the LDAP_LEVEL_* defines will be somewhat
self-explanatory.  The first seven levels are intended to mirror
the syslog levels.  Feedback is encouraged, but I'm primarily
interested in (in order of importance): 1) I haven't broken anything
2) everything works as intended 3) the mechanism is sufficiently
extensible and useful.  I realize that if the new logging is accepted,
a lot of work can go into actually putting more logging messages into
the code, but this can be an evolutionary process.  Thank you for your
cooperation and support.

# slapd.conf debugging options
debug           global     5
debug           operation  8
debug           transport  7
debug           connection 8
debug           filter     6
debug           backend    7
debug           liblber    5
debug           config     12
debug           acl        6
debug           cache      6
debug           index      7
debug           ldif       0
debug           sasl       0

logfile         /export/home/sasgwi/etc/openldap/slapd.log
### end debug

Gary D. Williams