In krb5.h
Ft typedef void
Fn *krb5_log_log_func_t const char *time const char *message void *data
Ft typedef void
Fn *krb5_log_close_func_t void *data
Ft krb5_error_code
Fn krb5_addlog_dest krb5_context context krb5_log_facility *facility const char *destination
Ft krb5_error_code
Fn krb5_addlog_func krb5_context context krb5_log_facility *facility int min int max krb5_log_log_func_t log krb5_log_close_func_t close void *data
Ft krb5_error_code
Fn krb5_closelog krb5_context context krb5_log_facility *facility
Ft krb5_error_code
Fn krb5_initlog krb5_context context const char *program krb5_log_facility **facility
Ft krb5_error_code
Fn krb5_log krb5_context context krb5_log_facility *facility int level const char *format ...
Ft krb5_error_code
Fn krb5_log_msg krb5_context context krb5_log_facility *facility char **reply int level const char *format ...
Ft krb5_error_code
Fn krb5_openlog krb5_context context const char *program krb5_log_facility **facility
Ft krb5_error_code
Fn krb5_vlog krb5_context context krb5_log_facility *facility int level const char *format va_list arglist
Ft krb5_error_code
Fn krb5_vlog_msg krb5_context context krb5_log_facility *facility char **reply int level const char *format va_list arglist
DESCRIPTION
These functions logs messages to one or more destinations.
The
Fn krb5_openlog
function creates a logging
Fa facility ,
that is used to log messages. A facility consists of one or more
destinations (which can be files or syslog or some other device). The
Fa program
parameter should be the generic name of the program that is doing the
logging. This name is used to lookup which destinations to use. This
information is contained in the
logging
section of the
krb5.conf
configuration file. If no entry is found for
Fa program ,
the entry for
default
is used, or if that is missing too,
SYSLOG
will be used as destination.
To close a logging facility, use the
Fn krb5_closelog
function.
To log a message to a facility use one of the functions
Fn krb5_log ,
Fn krb5_log_msg ,
Fn krb5_vlog ,
or
Fn krb5_vlog_msg .
The functions ending in
_msg
return in
Fa reply
a pointer to the message that just got logged. This string is allocated,
and should be freed with
Fn free .
The
Fa format
is a standard
Fn printf
style format string (but see the BUGS section).
If you want better control of where things gets logged, you can instead of using
Fn krb5_openlog
call
Fn krb5_initlog ,
which just initializes a facility, but doesn't define any actual logging
destinations. You can then add destinations with the
Fn krb5_addlog_dest
and
Fn krb5_addlog_func
functions. The first of these takes a string specifying a logging
destination, and adds this to the facility. If you want to do some
non-standard logging you can use the
Fn krb5_addlog_func
function, which takes a function to use when logging.
The
Fa log
function is called for each message with
Fa time
being a string specifying the current time, and
Fa message
the message to log.
Fa close
is called when the facility is closed. You can pass application specific data in the
Fa data
parameter. The
Fa min
and
Fa max
parameter are the same as in a destination (defined below). To specify a
max of infinity, pass -1.
Fn krb5_openlog
calls
Fn krb5_initlog
and then calls
Fn krb5_addlog_dest
for each destination found.
Destinations
The defined destinations (as specified in
krb5.conf
follows:
STDERR
This logs to the program's stderr.
FILE: /file
FILE= /file
Log to the specified file. The form using a colon appends to the file, the
form with an equal truncates the file. The truncating form keeps the file
open, while the appending form closes it after each log message (which
makes it possible to rotate logs). The truncating form is mainly for
compatibility with the MIT libkrb5.
DEVICE= /device
This logs to the specified device, at present this is the same as
FILE:/device
CONSOLE
Log to the console, this is the same as
DEVICE=/dev/console
SYSLOG [:priority [:facility]
]
Send messages to the syslog system, using priority, and facility. To
get the name for one of these, you take the name of the macro passed
to
syslog(3),
and remove the leading
LOG_( LOG_NOTICE
becomes
NOTICE )
The default values (as well as the values used for unrecognised
values), are
ERR
and
AUTH
respectively. See
syslog(3)
for a list of priorities and facilities.
Each destination may optionally be prepended with a range of logging
levels, specified as
min-max/
If the
Fa level
parameter to
Fn krb5_log
is within this range (inclusive) the message gets logged to this
destination, otherwise not. Either of the min and max valued may be
omitted, in this case min is assumed to be zero, and max is assumed to be
infinity. If you don't include a dash, both min and max gets set to the
specified value. If no range is specified, all messages gets logged.
This will log all messages from the
kdc
program with level 0 to
/var/log/kdc.log
other messages will be logged to syslog with priority
LOG_INFO
and facility
LOG_USER
All other programs will log all messages to their stderr.
These functions use
Fn asprintf
to format the message. If your operating system does not have a working
Fn asprintf ,
a replacement will be used. At present this replacement does not handle
some correct conversion specifications (like floating point numbers). Until
this is fixed, the use of these conversions should be avoided.
If logging is done to the syslog facility, these functions might not be
thread-safe, depending on the implementation of
Fn openlog ,
and
Fn syslog .