xlog Module

Elena-Ramona Modroiu


Edited by

Elena-Ramona Modroiu

Table of Contents

1. Admin Guide
1. Overview
2. Implemented Specifiers
3. Dependencies
3.1. Kamailio Modules
3.2. External Libraries or Applications
4. Parameters
4.1. buf_size (integer)
4.2. force_color (integer)
4.3. long_format (integer)
4.4. prefix (str)
4.5. log_facility (string)
4.6. log_colors (string)
4.7. methods_filter (int)
5. Functions
5.1. xlog([ [facility,] level,] format)
5.2. xdbg(format)
5.3. xlogl([ [facility,] level,] format)
5.4. xdbgl(format)
5.5. xlogm(level, format)

List of Examples

1.1. Set buf_size parameter
1.2. Set force_color parameter
1.3. Set long_format parameter
1.4. Set prefix parameter
1.5. log_facility example
1.6. log_colors example
1.7. Set methods_filter parameter
1.8. xlog usage
1.9. xdbg usage

Chapter 1. Admin Guide

1. Overview

This module provides the possibility to print user formatted log or debug messages from Kamailio scripts, similar to the printf function. A C-style printf specifier is replaced with a part of the SIP request or other variables from system.

2. Implemented Specifiers

In the xlog function, you use pseudo-variables, that are a part of Kamailio core and are used by other modules as well (e.g., avpops in the function avp_printf())

The most important changes from earlier versions of Kamailio are:

  • - '%' has been replaced by '$'

  • - to print a header, use $hdr(header_name[index]) instead of %{header_name[index]}

  • - to print an AVP, use now $avp([si]:avp_id[index]) instead of %{[si]:avp_id[index]} or $avp([$avp_alias[index]) instead of %{[$avp_alias[index]}

The full list of available pseudo-variables in Kamailio is available at: http://kamailio.org/wiki/

3. Dependencies

3.1. Kamailio Modules

The following modules must be loaded before this module:

  • No dependencies on other Kamailio modules. Note that many modules publish pseudovariables that you can use in this module. The core module for this is the pv module.

3.2. External Libraries or Applications

The following libraries or applications must be installed before running Kamailio with this module loaded:

  • None.

4. Parameters

4.1. buf_size (integer)

Maximum size of the log message.

Default value is 4096.

Example 1.1. Set buf_size parameter

modparam("xlog", "buf_size", 8192)

4.2. force_color (integer)

When set to 1, forces color codes in log messages even if log_stderror is set to 0.

Default value is 0.

Example 1.2. Set force_color parameter

modparam("xlog", "force_color", 0)

4.3. long_format (integer)

When set to 1, outputs the configuration file name in xlogl() and xdbgl() before the line number.

Default value is 0.

Example 1.3. Set long_format parameter

modparam("xlog", "long_format", 1)

4.4. prefix (str)

Prefix to be output before the log message.

Default value is "<script>: ".

Example 1.4. Set prefix parameter

modparam("xlog", "prefix", "-xlog: ")

4.5. log_facility (string)

Syslog facility to be used for the xlog output. By setting this, and configuring syslog, you can get the xlog messages in a separate syslog file than the debug messages issued from the source code.

Default value is NULL (unset - use same facility as source code debug messages).

Example 1.5. log_facility example

modparam("xlog", "log_facility", "LOG_DAEMON")

4.6. log_colors (string)

Update terminal colors used by the Kamailio core for log levels (when log_stderr=1 and log_color=1). The value has to be 'logname=colors', where colors is two characters specifying foreground and background in the same format as $C(xy) variable.

The parameter can be set many times. The value can also be a ';'-separated list of color specifications.

Default value is NULL.

Example 1.6. log_colors example

modparam("xlog", "log_colors", "L_ERR=cr")
modparam("xlog", "log_colors", "L_ERR=cr;L_WARN=px")

4.7. methods_filter (int)

The bitmask with internal SIP method ids to be ignored by xlogm() function. The value can be changed at runtime via cfg reload framework:

kamcmd cfg.set_now_int xlog methods_filter 15

To see the associated internal ids for SIP requests, look in source tree inside parser/msg_parser.h for enum request_method.

Default value is -1 (all SIP methods are ignored).

Example 1.7. Set methods_filter parameter

modparam("xlog", "long_format", 1)

5. Functions

5.1.  xlog([ [facility,] level,] format)

Output a formated log message.

Meaning of the parameters are as follows:

  • facility - The syslog facility that will be used for this single log message.

    If this parameter is missing, the implicit facility is either the facility set with the 'log_facility' module parameter or the core's log facility.

  • level - The level that will be used in LOG function. It can be:

    • L_ALERT - log level -5

    • L_BUG - log level -4

    • L_CRIT - log level -3

    • L_ERR - log level -1

    • L_WARN - log level 0

    • L_NOTICE - log level 1

    • L_INFO - log level 2

    • L_DBG - log level 3

    • $pv - any valid pseudo-variable, that has an integer value. See above options for valid log levels.

    If it is not a pseudo-variable, then what really matters is the third letter of the value. If the log level is higher than the debug global parameter, the message is not printed to syslog.

    If this parameter is missing, the implicit log level is 'L_ERR'.

  • format - The formatted string to be printed.

This function can be used from ANY_ROUTE.

Example 1.8. xlog usage

xlog("L_ERR", "time [$Tf] method ($rm) r-uri ($ru) 2nd via ($hdr(via[1]))\n");
xlog("time [$Tf] method ($rm) r-uri ($ru) 2nd via ($hdr(via[1]))\n");
$var(loglevel) = 2;
xlog("$var(loglevel)", "time [$Tf] method ($rm) r-uri ($ru)\n");
xlog("LOG_LOCAL3", "L_ERR", "this message will be sent to syslog facility LOG_LOCAL3\n");

5.2.  xdbg(format)

Print a formatted message using DBG function.

Meaning of the parameters is as follows:

  • format - The formatted string to be printed.

This function can be used from ANY_ROUTE.

Example 1.9. xdbg usage

xdbg("time $Cbx[$Tf]$Cxx method ($rm) r-uri ($ru)\n");

5.3.  xlogl([ [facility,] level,] format)

Similar to xlog(), in addition prints configuration file line number at the beginning of message.

5.4.  xdbgl(format)

Similar to xdbg(), in addition prints configuration file line number at the beginning of message.

5.5.  xlogm(level, format)

Similar to xlog(level, format), but skips writing the log messages for SIP requests and responses that match the SIP method id with methods_filter parameter value.