dialog_ng Module

Bogdan-Andrei Iancu

   Voice Sistem SRL

Carsten Bock

   ng-voice.com

Jason Penton

   Smile Communications

Richard Good

   Smile Communications

Edited by

Bogdan-Andrei Iancu

Edited by

Carsten Bock

Edited by

Jason Penton

Edited by

Richard Good

   Copyright © 2006 Voice Sistem SRL

   Copyright © 2011 Carsten Bock, http://www.ng-voice.com
     __________________________________________________________________

   Table of Contents

   1. Admin Guide

        1. Overview
        2. How it works
        3. Dialog profiling
        4. Dependencies

              4.1. Kamailio Modules
              4.2. External Libraries or Applications

        5. Parameters

              5.1. enable_stats (integer)
              5.2. hash_size (integer)
              5.3. rr_param (string)
              5.4. dlg_flag (integer)
              5.5. timeout_avp (string)
              5.6. default_timeout (integer)
              5.7. dlg_extra_hdrs (string)
              5.8. dlg_match_mode (integer)
              5.9. detect_spirals (integer)
              5.10. db_url (string)
              5.11. db_mode (integer)
              5.12. db_update_period (integer)
              5.13. db_fetch_rows (integer)
              5.14. table_name (string)
              5.15. profiles_with_value (string)
              5.16. profiles_no_value (string)
              5.17. bridge_controller (string)
              5.18. initial_cbs_inscript (string)

        6. Functions

              6.1. set_dlg_profile(profile,[value])
              6.2. unset_dlg_profile(profile,[value])
              6.3. is_in_profile(profile,[value])
              6.4. get_profile_size(profile,[value],size)
              6.5. dlg_isflagset(flag)
              6.6. dlg_setflag(flag)
              6.7. dlg_resetflag(flag)
              6.8. dlg_terminate
              6.9. dlg_refer(side, address)
              6.10. dlg_manage()
              6.11. dlg_bridge(from, to, op)
              6.12. dlg_get(callid, ftag, ttag)
              6.13. is_known_dlg()

        7. Exported statistics

              7.1. active_dialogs
              7.2. early_dialogs
              7.3. processed_dialogs
              7.4. expired_dialogs
              7.5. failed_dialogs

        8. MI Commands

              8.1. dlg_list
              8.2. dlg_list_ctx
              8.3. dlg_end_dlg
              8.4. dlg_terminate_dlg
              8.5. profile_get_size
              8.6. profile_list_dlgs
              8.7. dlg_bridge

        9. Exported RPC Functions

              9.1. dlg.list
              9.2. dlg.list_ctx
              9.3. dlg.dlg_list
              9.4. dlg.dlg_list_ctx
              9.5. dlg.end_dlg
              9.6. dlg.profile_get_size
              9.7. dlg.profile_list
              9.8. dlg.bridge_dlg

        10. Exported pseudo-variables

              10.1. $DLG_count
              10.2. $DLG_status
              10.3. $DLG_lifetime
              10.4. $dlg(...)
              10.5. $dlg_ctx(...)
              10.6. $dlg_var(key)

   2. Developer Guide

        1. Available Functions

              1.1. register_dlgcb (dialog, type, cb, param, free_param_cb)

              1.2. terminate_dlg (str callid, str ftag, str ttag, hdrs)
              1.3. set_dlg_var (dlg, key, val)
              1.4. get_dlg_var (dlg, key)
              1.5. get_current_dialog ()

   3. Frequently Asked Questions

   List of Examples

   1.1. Set hash_size parameter
   1.2. Set rr_param parameter
   1.3. Set dlg_flag parameter
   1.4. Set timeout_avp parameter
   1.5. Set default_timeout parameter
   1.6. Set dlf_extra_hdrs parameter
   1.7. Set detect_spirals parameter
   1.8. Set profiles_with_value parameter
   1.9. Set profiles_no_value parameter
   1.10. Set bridge_controller parameter
   1.11. set_dlg_profile usage
   1.12. unset_dlg_profile usage
   1.13. is_in_profile usage
   1.14. get_profile_size usage
   1.15. dlg_isflagset usage
   1.16. dlg_setflag usage
   1.17. dlg_resetflag usage
   1.18. dlg_terminate usage

Chapter 1. Admin Guide

   Table of Contents

   1. Overview
   2. How it works
   3. Dialog profiling
   4. Dependencies

        4.1. Kamailio Modules
        4.2. External Libraries or Applications

   5. Parameters

        5.1. enable_stats (integer)
        5.2. hash_size (integer)
        5.3. rr_param (string)
        5.4. dlg_flag (integer)
        5.5. timeout_avp (string)
        5.6. default_timeout (integer)
        5.7. dlg_extra_hdrs (string)
        5.8. dlg_match_mode (integer)
        5.9. detect_spirals (integer)
        5.10. db_url (string)
        5.11. db_mode (integer)
        5.12. db_update_period (integer)
        5.13. db_fetch_rows (integer)
        5.14. table_name (string)
        5.15. profiles_with_value (string)
        5.16. profiles_no_value (string)
        5.17. bridge_controller (string)
        5.18. initial_cbs_inscript (string)

   6. Functions

        6.1. set_dlg_profile(profile,[value])
        6.2. unset_dlg_profile(profile,[value])
        6.3. is_in_profile(profile,[value])
        6.4. get_profile_size(profile,[value],size)
        6.5. dlg_isflagset(flag)
        6.6. dlg_setflag(flag)
        6.7. dlg_resetflag(flag)
        6.8. dlg_terminate
        6.9. dlg_refer(side, address)
        6.10. dlg_manage()
        6.11. dlg_bridge(from, to, op)
        6.12. dlg_get(callid, ftag, ttag)
        6.13. is_known_dlg()

   7. Exported statistics

        7.1. active_dialogs
        7.2. early_dialogs
        7.3. processed_dialogs
        7.4. expired_dialogs
        7.5. failed_dialogs

   8. MI Commands

        8.1. dlg_list
        8.2. dlg_list_ctx
        8.3. dlg_end_dlg
        8.4. dlg_terminate_dlg
        8.5. profile_get_size
        8.6. profile_list_dlgs
        8.7. dlg_bridge

   9. Exported RPC Functions

        9.1. dlg.list
        9.2. dlg.list_ctx
        9.3. dlg.dlg_list
        9.4. dlg.dlg_list_ctx
        9.5. dlg.end_dlg
        9.6. dlg.profile_get_size
        9.7. dlg.profile_list
        9.8. dlg.bridge_dlg

   10. Exported pseudo-variables

        10.1. $DLG_count
        10.2. $DLG_status
        10.3. $DLG_lifetime
        10.4. $dlg(...)
        10.5. $dlg_ctx(...)
        10.6. $dlg_var(key)

1. Overview

   The dialog_ng module provides dialog awareness to the Kamailio proxy. Its
   functionality is to keep track of the current dialogs, to offer
   information about them (like how many dialogs are active) or to manage
   them. The module exports several functions that could be used directly
   from scripts. The dialog_ng module extends the original dialog module by
   providing support for forked calling and early dialog termination. It
   is the intention that the dialog_ng module will eventually replace the
   dialog module.

   The module, via an internal API, also provide the foundation to build
   on top of it more complex dialog-based functionalities via other
   Kamailio modules.

2. How it works

   To create the dialog associated to an initial request, the flag
   “dlg_flag” ( Section 5.4, “ dlg_flag (integer) ”) must be set before
   creating the corresponding transaction.

   The dialog is automatically destroyed when a “BYE” is received. In case
   of no “BYE”, the dialog lifetime is controlled via the default timeout
   (see “default_timeout” - Section 5.6, “ default_timeout (integer) ”)
   and custom timeout (see “timeout_avp” - Section 5.5, “ timeout_avp
   (string) ”). The dialog timeout is reset each time a sequential request
   passes.

3. Dialog profiling

   Dialog profiling is a mechanism that helps in classifying, sorting and
   keeping trace of certain types of dialogs, using whatever properties of
   the dialog (like caller, destination, type of calls, etc). Dialogs can
   be dynamically added in different (and several) profile tables -
   logically, each profile table can have a special meaning (like dialogs
   outside the domain, dialogs terminated to PSTN, etc).

   There are two types of profiles:
     * with no value - a dialog simply belongs to a profile. (like
       outbound calls profile). There is no other additional information
       to describe the dialog's belonging to the profile;
     * with value - a dialog belongs to a profile having a certain value
       (like in caller profile, where the value is the caller ID). The
       belonging of the dialog to the profile is strictly related to the
       value.

   A dialog can be added to multiple profiles in the same time.

   Profiles are visible (at the moment) in the request route (for initial
   and sequential requests) and in the branch, failure and reply routes of
   the original request.

4. Dependencies

   4.1. Kamailio Modules
   4.2. External Libraries or Applications

4.1. Kamailio Modules

   The following modules must be loaded before this module:
     * TM - Transaction module
     * RR - Record-Route module

4.2. External Libraries or Applications

   The following libraries or applications must be installed before
   running Kamailio with this module loaded:
     * None.

5. Parameters

   5.1. enable_stats (integer)
   5.2. hash_size (integer)
   5.3. rr_param (string)
   5.4. dlg_flag (integer)
   5.5. timeout_avp (string)
   5.6. default_timeout (integer)
   5.7. dlg_extra_hdrs (string)
   5.8. dlg_match_mode (integer)
   5.9. detect_spirals (integer)
   5.10. db_url (string)
   5.11. db_mode (integer)
   5.12. db_update_period (integer)
   5.13. db_fetch_rows (integer)
   5.14. table_name (string)
   5.15. profiles_with_value (string)
   5.16. profiles_no_value (string)
   5.17. bridge_controller (string)
   5.18. initial_cbs_inscript (string)

5.1.  enable_stats (integer)

   This function is currently not supported by the dialog_ng module. To be
   incorporated in the future.

5.2.  hash_size (integer)

   The size of the hash table internally used to keep the dialogs. A
   larger table is much faster but consumes more memory. The hash size
   must be a power of two number.

   IMPORTANT: If dialogs' information should be stored in a database, a
   constant hash_size should be used, otherwise the restoring process will
   not take place. If you really want to modify the hash_size you must
   delete all table's rows before restarting the server.

   Default value is “4096”.

   Example 1.1. Set hash_size parameter
...
modparam("dialog_ng", "hash_size", 1024)
...

5.3.  rr_param (string)

   Name of the Record-Route parameter to be added with the dialog cookie.
   It is used for the fast dialog matching of sequential requests.

   Default value is “did”.

   Example 1.2. Set rr_param parameter
...
modparam("dialog_ng", "rr_param", "xyz")
...

5.4.  dlg_flag (integer)

   Flag to be used for marking if a dialog should be constructed for the
   current request (this make sense only for initial requests).

   Default value is “none”.

   Example 1.3. Set dlg_flag parameter
...
modparam("dialog_ng", "dlg_flag", 4)
...

5.5.  timeout_avp (string)

   The specification of an AVP that contain a custom timeout (in seconds)
   for the dialog. It may be used only in a request (initial or
   sequential) context

   Default value is “none”.

   Example 1.4. Set timeout_avp parameter
...
modparam("dialog_ng", "timeout_avp", "$avp(i:10)")
...

5.6.  default_timeout (integer)

   The default dialog timeout (in seconds) if no custom one is set.

   Default value is “43200 (12 hours)”.

   Example 1.5. Set default_timeout parameter
...
modparam("dialog_ng", "default_timeout", 21600)
...

5.7.  dlg_extra_hdrs (string)

   A string containing the extra headers (full format, with EOH) to be
   added in the requests generated by the module (like BYEs).

   Default value is “NULL”.

   Example 1.6. Set dlf_extra_hdrs parameter
...
modparam("dialog_ng", "dlg_extra_hdrs", "Hint: credit expired\r\n")
...

5.8.  dlg_match_mode (integer)

   Deprecated - in the new dialog module we always match using DID ONLY

5.9.  detect_spirals (integer)

   Whether spirals (i.e., messages routed through the proxy multiple
   times) should be detected or not.

   If set to 0, spirals will not be detected and result in the generation
   of a new, possibly dangling dialog structure per occurring spiral. If
   set to 1, spirals are detected and internally mapped to existing dialog
   structures.

   Default value is 1.

   Example 1.7. Set detect_spirals parameter
...
modparam("dialog_ng", "detect_spirals", 1)
...

5.10.  db_url (string)

   Db storage not yet supported by dialog_ng - this to be done in future.

5.11.  db_mode (integer)

   Db storage not yet supported by dialog_ng - this to be done in future.

5.12.  db_update_period (integer)

   Db storage not yet supported by dialog_ng - this to be done in future.

5.13.  db_fetch_rows (integer)

   Db storage not yet supported by dialog_ng - this to be done in future.

5.14.  table_name (string)

   Db storage not yet supported by dialog_ng - this to be done in future.

5.15.  profiles_with_value (string)

   List of names for profiles with values.

   Default value is “empty”.

   Example 1.8. Set profiles_with_value parameter
...
modparam("dialog", "profiles_with_value", "caller ; my_profile")
...

5.16.  profiles_no_value (string)

   List of names for profiles without values.

   Default value is “empty”.

   Example 1.9. Set profiles_no_value parameter
...
modparam("dialog", "profiles_no_value", "inbound ; outbound")
...

5.17.  bridge_controller (string)

   SIP address to be used in From header when initiating a call bridge.

   Default value is “sip:controller@kamailio.org”.

   Example 1.10. Set bridge_controller parameter
...
modparam("dialog", "bridge_controller", "sip:ctd@kamailio.org")
...

5.18.  initial_cbs_inscript (string)

   This has been deprecated since dlg_manage has been removed.

6. Functions

   6.1. set_dlg_profile(profile,[value])
   6.2. unset_dlg_profile(profile,[value])
   6.3. is_in_profile(profile,[value])
   6.4. get_profile_size(profile,[value],size)
   6.5. dlg_isflagset(flag)
   6.6. dlg_setflag(flag)
   6.7. dlg_resetflag(flag)
   6.8. dlg_terminate
   6.9. dlg_refer(side, address)
   6.10. dlg_manage()
   6.11. dlg_bridge(from, to, op)
   6.12. dlg_get(callid, ftag, ttag)
   6.13. is_known_dlg()

6.1.  set_dlg_profile(profile,[value])

   Inserts the current dialog into a profile. Note that if the profile
   does not supports values, this will be silently discarded. Also, there
   is no check for inserting the same dialog in the same profile for
   multiple times.

   Meaning of the parameters is as follows:
     * profile - name of the profile to be added to;
     * value (optional) - string value to define the belonging of the
       dialog to the profile - note that the profile must support values.
       Pseudo-variables are supported.

   This function can be used from REQUEST_ROUTE, BRANCH_ROUTE, REPLY_ROUTE
   and FAILURE_ROUTE.

   Example 1.11.  set_dlg_profile usage
...
set_dlg_profile("inbound_call");
set_dlg_profile("caller","$fu");
...

6.2.  unset_dlg_profile(profile,[value])

   Removes the current dialog from a profile.

   Meaning of the parameters is as follows:
     * profile - name of the profile to be removed from;
     * value (optional) - string value to define the belonging of the
       dialog to the profile - note that the profile must support values.
       Pseudo-variables are supported.

   This function can be used from BRANCH_ROUTE, REPLY_ROUTE and
   FAILURE_ROUTE.

   Example 1.12.  unset_dlg_profile usage
...
unset_dlg_profile("inbound_call");
unset_dlg_profile("caller","$fu");
...

6.3.  is_in_profile(profile,[value])

   Checks if the current dialog belongs to a profile. If the profile
   supports values, the check can be reinforced to take into account a
   specific value - if the dialog was inserted into the profile for a
   specific value. If no value is passed, only the simply belonging of the
   dialog to the profile is checked. Note that if the profile does not
   supports values, this will be silently discarded.

   Meaning of the parameters is as follows:
     * profile - name of the profile to be checked against;
     * value (optional) - string value to further restrict the check.
       Pseudo-variables are supported.

   This function can be used from REQUEST_ROUTE, BRANCH_ROUTE, REPLY_ROUTE
   and FAILURE_ROUTE.

   Example 1.13.  is_in_profile usage
...
if (is_in_profile("inbound_call")) {
        log("this request belongs to a inbound call\n");
}
...
if (is_in_profile("caller","XX")) {
        log("this request belongs to a call of user XX\n");
}
...

6.4.  get_profile_size(profile,[value],size)

   Returns the number of dialogs belonging to a profile. If the profile
   supports values, the check can be reinforced to take into account a
   specific value - how many dialogs were inserted into the profile with a
   specific value. If no value is passed, only simply belonging of the
   dialog to the profile is checked. Note that if the profile does not
   supports values, this will be silently discarded.

   Meaning of the parameters is as follows:
     * profile - name of the profile to get the size for;
     * value (optional) - string value to further restrict the check.
       Pseudo-variables are supported;
     * size - an AVP or script variable to return the profile size in.

   This function can be used from REQUEST_ROUTE, BRANCH_ROUTE, REPLY_ROUTE
   and FAILURE_ROUTE.

   Example 1.14.  get_profile_size usage
...
if(get_profile_size("inbound_call","$avp(size)"))
    xlog("currently there are $avp(size) inbound calls\n");
...
if(get_profile_size("caller","$fu","$avp(size)"))
    xlog("currently, the user $fu has $avp(size) active outgoing calls\n");
...

6.5.  dlg_isflagset(flag)

   Check if the dialog flag is set or not.

   Meaning of the parameters is as follows:
     * flag - index of the flag - can be pseudo-variable.

   This function can be used from BRANCH_ROUTE, REQUEST_ROUTE,
   ONREPLY_ROUTE and FAILURE_ROUTE.

   Example 1.15.  dlg_isflagset usage
...
if(dlg_isflagset("1"))
{
    ...
}
...

6.6.  dlg_setflag(flag)

   Set the dialog flag.

   Meaning of the parameters is as follows:
     * flag - index of the flag - can be pseudo-variable.

   This function can be used from BRANCH_ROUTE, REQUEST_ROUTE,
   ONREPLY_ROUTE and FAILURE_ROUTE.

   Example 1.16.  dlg_setflag usage
...
dlg_setflag("1");
...

6.7.  dlg_resetflag(flag)

   Reset the dialog flag.

   Meaning of the parameters is as follows:
     * flag - index of the flag - can be pseudo-variable.

   This function can be used from BRANCH_ROUTE, REQUEST_ROUTE,
   ONREPLY_ROUTE and FAILURE_ROUTE.

   Example 1.17.  dlg_resetflag usage
...
redlg_setflag("1");
...

6.8.  dlg_terminate

   Terminates a dialog. In dialog_ng module this function now includes
   support for early as well as confirmed dialogs.

   Meaning of the parameters is as follows:
     * side - which side to terminate. It can be: caller, callee or both
       of them.
     * reason - reason for termination.

   This function can be used from BRANCH_ROUTE, REQUEST_ROUTE,
   ONREPLY_ROUTE and FAILURE_ROUTE.

   Example 1.18.  dlg_terminate usage
...
dlg_terminate("all", "Insufficient QoS");
...

6.9.  dlg_refer(side, address)

   This function is currently not supported by the dialog_ng module. To be
   incorporated in the future.

6.10.  dlg_manage()

   This has been deprecated in dialog_ng. Instead set dialog flag for
   initial INVITE and Route-parameter-callback execution for within-dialog
   requests.

6.11.  dlg_bridge(from, to, op)

   This function is currently not supported by the dialog_ng module. To be
   incorporated in the future.

6.12.  dlg_get(callid, ftag, ttag)

   This function is currently not supported by the dialog_ng module. To be
   incorporated in the future.

6.13.  is_known_dlg()

   This function is currently not supported by the dialog_ng module. To be
   incorporated in the future.

7. Exported statistics

   7.1. active_dialogs
   7.2. early_dialogs
   7.3. processed_dialogs
   7.4. expired_dialogs
   7.5. failed_dialogs

7.1.  active_dialogs

   This function is currently not supported by the dialog_ng module. To be
   incorporated in the future.

7.2.  early_dialogs

   This function is currently not supported by the dialog_ng module. To be
   incorporated in the future.

7.3.  processed_dialogs

   This function is currently not supported by the dialog_ng module. To be
   incorporated in the future.

7.4.  expired_dialogs

   This function is currently not supported by the dialog_ng module. To be
   incorporated in the future.

7.5.  failed_dialogs

   This function is currently not supported by the dialog_ng module. To be
   incorporated in the future.

8. MI Commands

   8.1. dlg_list
   8.2. dlg_list_ctx
   8.3. dlg_end_dlg
   8.4. dlg_terminate_dlg
   8.5. profile_get_size
   8.6. profile_list_dlgs
   8.7. dlg_bridge

8.1.  dlg_list

   Lists the description of a dialog or of all dialogs (calls). If only
   one dialogs is to be listed, the dialog identifiers are to be passed as
   parameter (callid and fromtag). In dialog_ng module this also now also
   lists all dlg_out entries for early dialogs.

   Name: dlg_list

   Parameters:
     * callid (optional) - callid if a single dialog to be listed.
     * from_tag (optional, but cannot be present without the callid
       parameter) - from tag (as per initial request) of the dialog to be
       listed. Note that if the from_tag is not specified, only dialogs
       created by a request without a from tag are matched, which will
       only occur with broken clients and is thus a very rare situation.

   MI FIFO Command Format:
                :dlg_list:_reply_fifo_file_
                _empty_line_
                :dlg_list:_reply_fifo_file_
                abcdrssfrs122444@192.168.1.1
                AAdfeEFF33

8.2.  dlg_list_ctx

   This function is currently not supported by the dialog_ng module. To be
   incorporated in the future.

8.3.  dlg_end_dlg

   This function is currently not supported by the dialog_ng module. To be
   incorporated in the future.

8.4.  dlg_terminate_dlg

   Terminates a singe dialog, identified by the call_id, ftag, ttag. In
   dialog_ng module this dialog can be terminated in the early or confirmed
   states.

   Name: dlg_terminate_dlg

   Parameters:
     * callid - callid of the dialog to be terminated.
     * ftag fromtag of dialog to be terminated.
     * ttag totag of dialog to be terminated.

   Note: Works for confirmed and early dialogs.

   MI FIFO Command Format:
                :dlg_terminate_dlg:_reply_fifo_file_
                abcdrssfrs122444@192.168.1.1
                AAdfeEFF33 ftag-1234 t-tag1234

8.5.  profile_get_size

   This function is currently not supported by the dialog_ng module. To be
   incorporated in the future.

8.6.  profile_list_dlgs

   This function is currently not supported by the dialog_ng module. To be
   incorporated in the future.

8.7.  dlg_bridge

   This function is currently not supported by the dialog_ng module. To be
   incorporated in the future.

9. Exported RPC Functions

   9.1. dlg.list
   9.2. dlg.list_ctx
   9.3. dlg.dlg_list
   9.4. dlg.dlg_list_ctx
   9.5. dlg.end_dlg
   9.6. dlg.profile_get_size
   9.7. dlg.profile_list
   9.8. dlg.bridge_dlg

9.1.  dlg.list

   This function is currently not supported by the dialog_ng module. To be
   incorporated in the future.

9.2.  dlg.list_ctx

   This function is currently not supported by the dialog_ng module. To be
   incorporated in the future.

9.3.  dlg.dlg_list

   This function is currently not supported by the dialog_ng module. To be
   incorporated in the future.

9.4.  dlg.dlg_list_ctx

   This function is currently not supported by the dialog_ng module. To be
   incorporated in the future.

9.5.  dlg.end_dlg

   This function is currently not supported by the dialog_ng module. To be
   incorporated in the future.

9.6.  dlg.profile_get_size

   This function is currently not supported by the dialog_ng module. To be
   incorporated in the future.

9.7.  dlg.profile_list

   This function is currently not supported by the dialog_ng module. To be
   incorporated in the future.

9.8.  dlg.bridge_dlg

   This function is currently not supported by the dialog_ng module. To be
   incorporated in the future.

10. Exported pseudo-variables

   10.1. $DLG_count
   10.2. $DLG_status
   10.3. $DLG_lifetime
   10.4. $dlg(...)
   10.5. $dlg_ctx(...)
   10.6. $dlg_var(key)

10.1.  $DLG_count

   This function is currently not supported by the dialog_ng module. To be
   incorporated in the future.

10.2.  $DLG_status

   This function is currently not supported by the dialog_ng module. To be
   incorporated in the future.

10.3.  $DLG_lifetime

   This function is currently not supported by the dialog_ng module. To be
   incorporated in the future.

10.4.  $dlg(...)

   This function is currently not supported by the dialog_ng module. To be
   incorporated in the future.

10.5.  $dlg_ctx(...)

   This function is currently not supported by the dialog_ng module. To be
   incorporated in the future.

10.6.  $dlg_var(key)

   This function is currently not supported by the dialog_ng module. To be
   incorporated in the future.

Chapter 2. Developer Guide

   Table of Contents

   1. Available Functions

        1.1. register_dlgcb (dialog, type, cb, param, free_param_cb)
        1.2. terminate_dlg (str callid, str ftag, str ttag, hdrs)
        1.3. set_dlg_var (dlg, key, val)
        1.4. get_dlg_var (dlg, key)
        1.5. get_current_dialog ()

1. Available Functions

   1.1. register_dlgcb (dialog, type, cb, param, free_param_cb)
   1.2. terminate_dlg (str callid, str ftag, str ttag, hdrs)
   1.3. set_dlg_var (dlg, key, val)
   1.4. get_dlg_var (dlg, key)
   1.5. get_current_dialog ()

1.1.  register_dlgcb (dialog, type, cb, param, free_param_cb)

   Register a new callback to the dialog.

   Meaning of the parameters is as follows:
     * struct dlg_cell* dlg - dialog to register callback to. If maybe
       NULL only for DLGCB_CREATED callback type, which is not a per
       dialog type.
     * int type - types of callbacks; more types may be register for the
       same callback function; only DLGCB_CREATED must be register alone.
       Possible types:
          + DLGCB_LOADED
          + DLGCB_CREATED - called when a new dialog is created - it's a
            global type (not associated to any dialog)
          + DLGCB_FAILED - called when the dialog was negatively replied
            (non-2xx) - it's a per dialog type.
          + DLGCB_CONFIRMED_NA - called when the dialog is confirmed (2xx
            replied) but the setup-concluding ACK message from the caller
            is yet pending - it's a per dialog type.
          + DLGCB_CONFIRMED - called when the dialog is confirmed (2xx
            replied) and the setup-concluding ACK message from the caller
            has been seen - it's a per dialog type.
          + DLGCB_REQ_WITHIN - called when the dialog matches a sequential
            request (excluding setup-concluding ACK messages which are
            handled in DLGCB_CONFIRMED) - it's a per dialog type.
          + DLGCB_TERMINATED - called when the dialog is terminated via
            BYE - it's a per dialog type.
          + DLGCB_TERMINATED_CONFIRMED - called when response to a BYE
            request is received - it's a per dialog type.
          + DLGCB_EXPIRED - called when the dialog expires without
            receiving a BYE - it's a per dialog type.
          + DLGCB_EARLY - called when the dialog is created in an early
            state (18x replied) - it's a per dialog type.
          + DLGCB_RESPONSE_FWDED - called when the dialog matches a reply
            to the initial INVITE request - it's a per dialog type.
          + DLGCB_RESPONSE_WITHIN - called when the dialog matches a reply
            to a subsequent in dialog request - it's a per dialog type.
          + DLGCB_MI_CONTEXT - called when the mi dlg_list_ctx command is
            invoked - it's a per dialog type.
          + DLGCB_SPIRALED - called when the dialog matches a spiraling
            request - it's a per dialog type.
          + DLGCB_DESTROY
     * dialog_cb cb - callback function to be called. Prototype is: “void
       (dialog_cb) (struct dlg_cell* dlg, int type, struct dlg_cb_params *
       params); ”
     * void *param - parameter to be passed to the callback function.
     * param_free callback_param_free - callback function to be called to
       free the param. Prototype is: “void (param_free_cb) (void *param);”

1.2.  terminate_dlg (str callid, str ftag, str ttag, hdrs)

   Terminate a Dialog identified by callid, ftag and ttag in early or
   confirmed state.

   Meaning of parameters is as follows:
     * str* callid - callid of dialog to terminate.
     * str* ftag - from_tag of dialog to terminate.
     * str* ttag - to tag of dialog to terminate.
     * str* hdrs - string containg extra headers (full format) to be added
       to the BYE requests of the dialog.

1.3.  set_dlg_var (dlg, key, val)

   Add a variable to the dialog structure

   Meaning of parameters is as follows:
     * struct dlg_cell* dlg - dialog to add to.
     * str* key - Name of the variable.
     * str* val - Value of the variable.

1.4.  get_dlg_var (dlg, key)

   Retrieves a variable attached to the dialog structure

   Meaning of parameters is as follows:
     * struct dlg_cell* dlg - dialog to get the variable from.
     * str* key - Name of the variable.

1.5.  get_current_dialog ()

   Get the current dialog for a message, if exists

Chapter 3. Frequently Asked Questions

   3.1. What happend with “use_tight_match” parameter?
   3.2. Why is there a dialog_ng module and a dialog module?
   3.3. Where can I find more about Kamailio?
   3.4. Where can I post a question about this module?
   3.5. How can I report a bug?

   3.1.

       What happend with “use_tight_match” parameter?

       The parameter was removed with version 1.3 as the option of tight
       matching became mandatory and not configurable. Now, the tight matching
       is done all the time (when using DID matching).

   3.2.

       Why is there a dialog_ng module and a dialog module?

       The dialog_ng module addresses shortcomings in the intial dialog module
       design. It makes some large changes to the API and therefore must be
       introduced slowly. It is currently in the early development stages.
       Eventually the dialog_ng module should replace the dialog module.

   3.3.

       Where can I find more about Kamailio?

       Take a look at http://www.kamailio.org/.

   3.4.

       Where can I post a question about this module?

       First at all check if your question was already answered on one of our
       mailing lists:
         * User Mailing List -
           http://lists.sip-router.org/cgi-bin/mailman/listinfo/sr-users
         * Developer Mailing List -
           http://lists.sip-router.org/cgi-bin/mailman/listinfo/sr-dev

       E-mails regarding any stable Kamailio release should be sent to
       <sr-users@lists.sip-router.org> and e-mails regarding development
       versions should be sent to <sr-dev@lists.sip-router.org>.

       If you want to keep the mail private, send it to
       <sr-users@lists.sip-router.org>.

   3.5.

       How can I report a bug?

       Please follow the guidelines provided at:
       http://sip-router.org/tracker.
