dialog Module

Bogdan-Andrei Iancu

   Voice Sistem SRL

Carsten Bock

   ng-voice.com

Edited by

Bogdan-Andrei Iancu

Edited by

Carsten Bock

Edited by

Alex Balashov

   <abalashov@evaristesys.com>

   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. callid_column (string)
              5.16. from_uri_column (string)
              5.17. from_tag_column (string)
              5.18. to_uri_column (string)
              5.19. to_tag_column (string)
              5.20. caller_cseq_column (string)
              5.21. callee_cseq_column (string)
              5.22. caller_route_column (string)
              5.23. callee_route_column (string)
              5.24. caller_contact_column (string)
              5.25. callee_contact_column (string)
              5.26. caller_sock_column (string)
              5.27. callee_sock_column (string)
              5.28. h_id_column (string)
              5.29. h_entry_column (string)
              5.30. state_column (string)
              5.31. start_time_column (string)
              5.32. timeout_column (string)
              5.33. sflags_column (string)
              5.34. toroute_column (string)
              5.35. vars_table_name (string)
              5.36. vars_h_id_column (string)
              5.37. vars_h_entry_column (string)
              5.38. vars_key_column (string)
              5.39. vars_value_column (string)
              5.40. profiles_with_value (string)
              5.41. profiles_no_value (string)
              5.42. bridge_controller (string)
              5.43. bridge_contact (string)
              5.44. initial_cbs_inscript (int)
              5.45. send_bye (int)
              5.46. wait_ack (int)
              5.47. ka_timer (int)
              5.48. ka_interval (int)

        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_bye(side)
              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()
              6.14. dlg_set_timeout(timeout [, h_entry, h_id])
              6.15. dlg_set_timeout_by_profile(profile, [value], timeout)
              6.16. dlg_set_property(attr)

        7. 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)

        11. Event Routes

              11.1. event_route[dialog:start]
              11.2. event_route[dialog:end]
              11.3. event_route[dialog:failed]

   2. Developer Guide

        1. Available Functions

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

              1.2. terminate_dlg (dlg, hdrs)

   3. Frequently Asked Questions

   List of Examples

   1.1. Set enable_stats parameter
   1.2. Set hash_size parameter
   1.3. Set rr_param parameter
   1.4. Set dlg_flag parameter
   1.5. Set timeout_avp parameter
   1.6. Set default_timeout parameter
   1.7. Set dlf_extra_hdrs parameter
   1.8. Set dlg_match_mode parameter
   1.9. Set detect_spirals parameter
   1.10. Set db_url parameter
   1.11. Set db_mode parameter
   1.12. Set db_update_period parameter
   1.13. Set db_fetch_rows parameter
   1.14. Set table_name parameter
   1.15. Set callid_column parameter
   1.16. Set from_uri_column parameter
   1.17. Set from_tag_column parameter
   1.18. Set to_uri_column parameter
   1.19. Set to_tag_column parameter
   1.20. Set caller_cseq_column parameter
   1.21. Set callee_cseq_column parameter
   1.22. Set caller_route_column parameter
   1.23. Set to_route_column parameter
   1.24. Set caller_contact_column parameter
   1.25. Set callee_contact_column parameter
   1.26. Set caller_sock_column parameter
   1.27. Set callee_sock_column parameter
   1.28. Set h_id_column parameter
   1.29. Set h_entry_column parameter
   1.30. Set state_column parameter
   1.31. Set start_time_column parameter
   1.32. Set timeout_column parameter
   1.33. Set sflags_column parameter
   1.34. Set toroute_column parameter
   1.35. Set vars_table_name parameter
   1.36. Set vars_h_id_column parameter
   1.37. Set vars_h_entry_column parameter
   1.38. Set vars_key_column parameter
   1.39. Set vars_value_column parameter
   1.40. Set profiles_with_value parameter
   1.41. Set profiles_no_value parameter
   1.42. Set bridge_controller parameter
   1.43. Set bridge_contact parameter
   1.44. Set initial_cbs_inscript parameter
   1.45. Set send_bye parameter
   1.46. Set wait_ack parameter
   1.47. Set ka_timer parameter
   1.48. Set ka_interval parameter
   1.49. set_dlg_profile usage
   1.50. unset_dlg_profile usage
   1.51. is_in_profile usage
   1.52. get_profile_size usage
   1.53. dlg_isflagset usage
   1.54. dlg_setflag usage
   1.55. dlg_resetflag usage
   1.56. dlg_bye usage
   1.57. dlg_refer usage
   1.58. dlg_manage usage
   1.59. dlg_bridge usage
   1.60. dlg_get usage
   1.61. is_known_dlg() usage
   1.62. dlg_set_timeout usage
   1.63. dlg_set_timeout_by_profile usage
   1.64. dlg_set_property 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. callid_column (string)
        5.16. from_uri_column (string)
        5.17. from_tag_column (string)
        5.18. to_uri_column (string)
        5.19. to_tag_column (string)
        5.20. caller_cseq_column (string)
        5.21. callee_cseq_column (string)
        5.22. caller_route_column (string)
        5.23. callee_route_column (string)
        5.24. caller_contact_column (string)
        5.25. callee_contact_column (string)
        5.26. caller_sock_column (string)
        5.27. callee_sock_column (string)
        5.28. h_id_column (string)
        5.29. h_entry_column (string)
        5.30. state_column (string)
        5.31. start_time_column (string)
        5.32. timeout_column (string)
        5.33. sflags_column (string)
        5.34. toroute_column (string)
        5.35. vars_table_name (string)
        5.36. vars_h_id_column (string)
        5.37. vars_h_entry_column (string)
        5.38. vars_key_column (string)
        5.39. vars_value_column (string)
        5.40. profiles_with_value (string)
        5.41. profiles_no_value (string)
        5.42. bridge_controller (string)
        5.43. bridge_contact (string)
        5.44. initial_cbs_inscript (int)
        5.45. send_bye (int)
        5.46. wait_ack (int)
        5.47. ka_timer (int)
        5.48. ka_interval (int)

   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_bye(side)
        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()
        6.14. dlg_set_timeout(timeout [, h_entry, h_id])
        6.15. dlg_set_timeout_by_profile(profile, [value], timeout)
        6.16. dlg_set_property(attr)

   7. 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)

   11. Event Routes

        11.1. event_route[dialog:start]
        11.2. event_route[dialog:end]
        11.3. event_route[dialog:failed]

1. Overview

   Kamailio can behave as a stateful proxy through the TM module. However,
   "stateful" in this context refers to transaction state, not dialog
   state. Certain applications benefit from the proxy's awareness of
   "calls", not just SIP transactions.

   For example, a common need is to limit the number of calls that can be
   made concurrently by an endpoint, account, user group, etc. In order to
   count the number of calls in progress, it is necessary for the proxy to
   be aware of whole dialogs, not just transactions, and to provide some
   means of programmatically classifying these dialogs. This is just one
   common application discussed for illustrative purposes; there are many
   others.

   The dialog module provides dialog awareness for the Kamailio proxy. Its
   functionality is to keep track of the current dialogs, to offer
   information about them (e.g. how many dialogs are active), and to
   manage various characteristics of dialogs. The module exports several
   functions that could be used directly from the configuration route
   script.

   This module also provides a foundational API on which to build more
   complex dialog-oriented functionality in other Kamailio modules.

2. How it works

   To create the dialog associated with 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
   is processed.

3. Dialog profiling

   Dialog profiling is a mechanism that helps in classifying, sorting and
   keeping track of certain types of dialogs. The classification criteria
   can be any attributes desired by the user; they can come from SIP
   message attributes, other pseudo-variables, custom values, etc. Dialogs
   can be dynamically added into one or more profile tables. Logically,
   each profile table can have a special meaning (like dialogs outside the
   domain, dialogs terminated to the PSTN, etc.).

   There are two types of profiles:
     * with no value - a dialog simply belongs to a profile (for instance,
       an outbound calls profile). There is no other additional
       information to describe the dialog beyond its membership in the
       profile per se.
     * with value - a dialog belongs to a profile having a certain value
       (like in a caller profile, where the value is the caller ID). The
       membership of the dialog in the profile is strictly related to the
       value. For example, if the account ID of the caller is stored in
       the pseudo-variable $var(account_id), you can use $var(account_id)
       as a value/key by which to group dialogs so that you can count the
       number of open dialogs for each account, enforce concurrent call
       limits as necessary, etc.

   A dialog can be added to multiple profiles at 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. callid_column (string)
   5.16. from_uri_column (string)
   5.17. from_tag_column (string)
   5.18. to_uri_column (string)
   5.19. to_tag_column (string)
   5.20. caller_cseq_column (string)
   5.21. callee_cseq_column (string)
   5.22. caller_route_column (string)
   5.23. callee_route_column (string)
   5.24. caller_contact_column (string)
   5.25. callee_contact_column (string)
   5.26. caller_sock_column (string)
   5.27. callee_sock_column (string)
   5.28. h_id_column (string)
   5.29. h_entry_column (string)
   5.30. state_column (string)
   5.31. start_time_column (string)
   5.32. timeout_column (string)
   5.33. sflags_column (string)
   5.34. toroute_column (string)
   5.35. vars_table_name (string)
   5.36. vars_h_id_column (string)
   5.37. vars_h_entry_column (string)
   5.38. vars_key_column (string)
   5.39. vars_value_column (string)
   5.40. profiles_with_value (string)
   5.41. profiles_no_value (string)
   5.42. bridge_controller (string)
   5.43. bridge_contact (string)
   5.44. initial_cbs_inscript (int)
   5.45. send_bye (int)
   5.46. wait_ack (int)
   5.47. ka_timer (int)
   5.48. ka_interval (int)

5.1. enable_stats (integer)

   If statistics support should be enabled or not. Via statistics
   variables, the module provide information about the dialog processing.
   Set it to zero to disable or to non-zero to enable it.

   Default value is "1 (enabled)".

   Example 1.1. Set enable_stats parameter
...
modparam("dialog", "enable_stats", 0)
...

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.

   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 1.2. Set hash_size parameter
...
modparam("dialog", "hash_size", 1024)
...

5.3. rr_param (string)

   Name of the Record-Route parameter used to store the dialog cookie. It
   is used for the fast matching of sequential requests to tracked
   dialogs.

   Default value is "did".

   Example 1.3. Set rr_param parameter
...
modparam("dialog", "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 1.4. Set dlg_flag parameter
...
modparam("dialog", "dlg_flag", 4)
...

5.5. timeout_avp (string)

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

   Default value is "none".

   Example 1.5. Set timeout_avp parameter
...
modparam("dialog", "timeout_avp", "$avp(i:10)")
...

5.6. default_timeout (integer)

   The default dialog timeout (in seconds), in the absence of a custom
   value provided in an AVP.

   Default value is "43200 (12 hours)".

   Example 1.6. Set default_timeout parameter
...
modparam("dialog", "default_timeout", 21600)
...

5.7. dlg_extra_hdrs (string)

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

   Default value is "NULL".

   Example 1.7. Set dlf_extra_hdrs parameter
...
modparam("dialog", "dlg_extra_hdrs", "Hint: credit expired\r\n")
...

5.8. dlg_match_mode (integer)

   How the sequential requests should be matched against the known
   dialogs. The modes are a combination of matching based on a cookie
   (DID) stored as cookie in Record-Route header and matching based on SIP
   elements (as in RFC 3261).

   The supported modes are:
     * 0 - DID_ONLY - the match is done exclusively based on DID;
     * 1 - DID_FALLBACK - the match is first tried based on DID and if not
       present, it will fall back to SIP matching;
     * 2 - DID_NONE - the match is done exclusively based on SIP elements;
       no DID information is added in RR.

   Default value is "0 (DID_ONLY)".

   Example 1.8. Set dlg_match_mode parameter
...
modparam("dialog", "dlg_match_mode", 1)
...

5.9. detect_spirals (integer)

   Whether spirals (i.e., messages routed through the proxy multiple
   times) should be detected.

   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 1.9. Set detect_spirals parameter
...
modparam("dialog", "detect_spirals", 1)
...

5.10. db_url (string)

   If you want to store the information about the dialogs in a database, a
   database URL must be specified.

   Default value is "mysql://kamailio:kamailiorw@localhost/kamailio".

   Example 1.10. Set db_url parameter
...
modparam("dialog", "db_url", "dbdriver://username:password@dbhost/dbname")
...

5.11. db_mode (integer)

   Mode of synchronisation of dialog information from memory to an
   underlying database (if desired):

   The supported modes are:
     * 0 - NO_DB - the memory content is not flushed into DB;
     * 1 - REALTIME - any dialog information changes will be reflected
       into the database immediatly.
     * 2 - DELAYED - the dialog information changes will be flushed into
       DB periodically, based on a timer routine.
     * 3 - SHUTDOWN - the dialog information will be flushed into DB only
       at shutdown - no runtime updates.

   Default value is "0".

   Example 1.11. Set db_mode parameter
...
modparam("dialog", "db_mode", 1)
...

5.12. db_update_period (integer)

   The interval (seconds) at which to update dialogs' information, if you
   chose to store the dialogs' info at a given interval. Too short an
   interval will generate intensive database operations, while an
   excessively long one will miss dialogs with a short lifetime.

   Default value is "60".

   Example 1.12. Set db_update_period parameter
...
modparam("dialog", "db_update_period", 120)
...

5.13. db_fetch_rows (integer)

   The number of the rows to be fetched at once from database when loading
   the dialog records at startup from the database. This value can be used
   to tune the load time at startup. For 1MB of private memory (default),
   it should be below 400. The database driver must support the
   fetch_result() capability. A value of 0 means the functionality is
   disabled.

   Default value is "200".

   Example 1.13. Set db_fetch_rows parameter
...
modparam("dialog", "db_fetch_rows", 500)
...

5.14. table_name (string)

   If you want to store the information about the dialogs in a database a
   table name must be specified.

   Default value is "dialog".

   Example 1.14. Set table_name parameter
...
modparam("dialog", "table_name", "my_dialog")
...

5.15. callid_column (string)

   The column name in the database to store the dialogs' callid.

   Default value is "callid".

   Example 1.15. Set callid_column parameter
...
modparam("dialog", "callid_column", "callid_c_name")
...

5.16. from_uri_column (string)

   The column name in the database to store the caller's sip address.

   Default value is "from_uri".

   Example 1.16. Set from_uri_column parameter
...
modparam("dialog", "from_uri_column", "from_uri_c_name")
...

5.17. from_tag_column (string)

   The column name in the database to store the From tag from the INVITE
   request.

   Default value is "from_tag".

   Example 1.17. Set from_tag_column parameter
...
modparam("dialog", "from_tag_column", "from_tag_c_name")
...

5.18. to_uri_column (string)

   The column name in the database to store the callee's sip address.

   Default value is "to_uri".

   Example 1.18. Set to_uri_column parameter
...
modparam("dialog", "to_uri_column", "to_uri_c_name")
...

5.19. to_tag_column (string)

   The column name in the database to store the To tag from the 200 OK
   response to the INVITE request, if present.

   Default value is "to_tag".

   Example 1.19. Set to_tag_column parameter
...
modparam("dialog", "to_tag_column", "to_tag_c_name")
...

5.20. caller_cseq_column (string)

   The column name in the database to store the cseq from caller side.

   Default value is "caller_cseq".

   Example 1.20. Set caller_cseq_column parameter
...
modparam("dialog", "caller_cseq_column", "column_name")
...

5.21. callee_cseq_column (string)

   The column name in the database to store the cseq from callee side.

   Default value is "callee_cseq".

   Example 1.21. Set callee_cseq_column parameter
...
modparam("dialog", "callee_cseq_column", "column_name")
...

5.22. caller_route_column (string)

   The column name in the database to store the route records from caller
   side (proxy to caller).

   Default value is "caller_route_set".

   Example 1.22. Set caller_route_column parameter
...
modparam("dialog", "caller_route_column", "column_name")
...

5.23. callee_route_column (string)

   The column name in the database to store the route records from callee
   side (proxy to callee).

   Default value is "callee_route_set".

   Example 1.23. Set to_route_column parameter
...
modparam("dialog", "callee_route_column", "column_name")
...

5.24. caller_contact_column (string)

   The column name in the database to store the caller's contact uri.

   Default value is "from_contact".

   Example 1.24. Set caller_contact_column parameter
...
modparam("dialog", "caller_contact_column", "column_name")
...

5.25. callee_contact_column (string)

   The column name in the database to store the callee's contact uri.

   Default value is "callee_contact".

   Example 1.25. Set callee_contact_column parameter
...
modparam("dialog", "callee_contact_column", "column_name")
...

5.26. caller_sock_column (string)

   The column name in the database to store the information about the
   local interface receiving the traffic from caller.

   Default value is "caller_sock".

   Example 1.26. Set caller_sock_column parameter
...
modparam("dialog", "caller_sock_column", "column_name")
...

5.27. callee_sock_column (string)

   The column name in the database to store information about the local
   interface receiving the traffic from callee.

   Default value is "callee_contact".

   Example 1.27. Set callee_sock_column parameter
...
modparam("dialog", "callee_sock_column", "column_name")
...

5.28. h_id_column (string)

   The column name in the database to store the dialogs' hash id
   information.

   Default value is "hash_id".

   Example 1.28. Set h_id_column parameter
...
modparam("dialog", "h_id_column", "hash_id_c_name")
...

5.29. h_entry_column (string)

   The column name in the database to store the dialogs' hash entry
   information.

   Default value is "hash_entry".

   Example 1.29. Set h_entry_column parameter
...
modparam("dialog", "h_entry_column", "h_entry_c_name")
...

5.30. state_column (string)

   The column name in the database to store the dialogs' state
   information.

   Default value is "state".

   Example 1.30. Set state_column parameter
...
modparam("dialog", "state_column", "state_c_name")
...

5.31. start_time_column (string)

   The column name in the database to store the dialogs' start time
   information.

   Default value is "start_time".

   Example 1.31. Set start_time_column parameter
...
modparam("dialog", "start_time_column", "start_time_c_name")
...

5.32. timeout_column (string)

   The column name in the database to store the dialogs' timeout.

   Default value is "timeout".

   Example 1.32. Set timeout_column parameter
...
modparam("dialog", "timeout_column", "timeout_c_name")
...

5.33. sflags_column (string)

   The column name in the database to store the script flags.

   Default value is "sflags".

   Example 1.33. Set sflags_column parameter
...
modparam("dialog", "sflags_column", "s_flags")
...

5.34. toroute_column (string)

   The column name in the database to store the index of the route to be
   executed at timeout.

   Default value is "toroute".

   Example 1.34. Set toroute_column parameter
...
modparam("dialog", "toroute_column", "timeout_route")
...

5.35. vars_table_name (string)

   If you want to store the variables for a dialog in a database a table
   name must be specified.

   Default value is "dialog_vars".

   Example 1.35. Set vars_table_name parameter
...
modparam("dialog", "vars_table_name", "my_dialog_vars")
...

5.36. vars_h_id_column (string)

   The column name in the database to store the dialogs' hash id
   information (as a reference to the dialog table).

   Default value is "hash_id".

   Example 1.36. Set vars_h_id_column parameter
...
modparam("dialog", "vars_h_id_column", "vars_h_id_name")
...

5.37. vars_h_entry_column (string)

   The column name in the database to store the dialogs' hash entry
   information (as a reference to the dialog table).

   Default value is "hash_entry".

   Example 1.37. Set vars_h_entry_column parameter
...
modparam("dialog", "vars_h_entry_column", "vars_h_entry_name")
...

5.38. vars_key_column (string)

   The column name in the database to store the keys of a variable.

   Default value is "dialog_key".

   Example 1.38. Set vars_key_column parameter
...
modparam("dialog", "vars_key_column", "vars_key_name")
...

5.39. vars_value_column (string)

   The column name in the database to store the keys of a variable.

   Default value is "dialog_value".

   Example 1.39. Set vars_value_column parameter
...
modparam("dialog", "vars_value_column", "vars_value_name")
...

5.40. profiles_with_value (string)

   List of names for profiles with values.

   Default value is "empty".

   Example 1.40. Set profiles_with_value parameter
...
modparam("dialog", "profiles_with_value", "caller ; my_profile")
...

5.41. profiles_no_value (string)

   List of names for profiles without values.

   Default value is "empty".

   Example 1.41. Set profiles_no_value parameter
...
modparam("dialog", "profiles_no_value", "inbound ; outbound")
...

5.42. bridge_controller (string)

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

   Default value is "sip:controller@kamailio.org".

   Example 1.42. Set bridge_controller parameter
...
modparam("dialog", "bridge_controller", "sip:ctd@kamailio.org")
...

5.43. bridge_contact (string)

   SIP address to be used in Contact header when doing a call bridge.

   Default value is "sip:controller@kamailio.org:5060".

   Example 1.43. Set bridge_contact parameter
...
modparam("dialog", "bridge_contact", "sip:ctd@127.0.0.1:5060")
...

5.44. initial_cbs_inscript (int)

   If the initial dialog callbacks (i.e., DLGCB_CREATED and
   DLGCB_SPIRALED) should be executed in-script or post-script. If
   dlg_manage() is not used, the setting of this parameter does not
   matter; otherwise, initial callbacks will be executed directly after
   dlg_manage() is called if this parameter is enabled. If it is disabled,
   initial callback execution will be postponed until configuration script
   execution completes.

   The supported values are:
     * 0 - POST-SCRIPT - execute initial callbacks after the script
       completes;
     * 1 - IN-SCRIPT - execute initial callbacks during script execution,
       i.e., right after dlg_manage() is called;

   Default value is "1".

   Example 1.44. Set initial_cbs_inscript parameter
...
modparam("dialog", "initial_cbs_inscript", 0)
...

5.45. send_bye (int)

   If set to 1, BYE requests will be sent out for each dialog that timed
   out. It is an alternative to $dlg_ctx(timeout_bye)=1 for all dialogs.

   Default value is "0".

   Example 1.45. Set send_bye parameter
...
modparam("dialog", "send_bye", 1)
...

5.46. wait_ack (int)

   If set to 1, dialog will be keept a bit longer in memory in order to
   absorb the ACK negative replies of initial INVITE. If not, the dialog
   is destroyed when negative reply is sent out (less internal
   complexity).

   Default value is "1".

   Example 1.46. Set wait_ack parameter
...
modparam("dialog", "wait_ack", 0)
...

5.47. ka_timer (int)

   Keep-alive timer step - how often to execute the callback to send
   dialog keep alives (SIP OPTIONS requests within dialog). The value
   represents the number of seconds.

   Default value is "0" (no keep alive).

   Example 1.47. Set ka_timer parameter
...
modparam("dialog", "ka_timer", 10)
...

5.48. ka_interval (int)

   The interval between keep alives within dialog (SIP OPTIONS requests),
   sent to caller or callee. The keep alive request will be sent by the
   first callback fired by KA timer after the ka_interval elapsed from
   dialog setup or previous keep-alive. The value represents the number of
   seconds.

   Default value is "0" (no keep alive).

   Example 1.48. Set ka_interval parameter
...
modparam("dialog", "ka_interval", 300)
...

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_bye(side)
   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()
   6.14. dlg_set_timeout(timeout [, h_entry, h_id])
   6.15. dlg_set_timeout_by_profile(profile, [value], timeout)
   6.16. dlg_set_property(attr)

6.1. set_dlg_profile(profile,[value])

   Inserts the current dialog into a profile. Note that if the profile
   does not support values, they will be silently discarded. Also, there
   is no check for inserting the same dialog into the same profile
   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 membership of the
       dialog in 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 1.49. 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 1.50. 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 membership of the
   dialog in the profile per se is checked. Note that if the profile does
   not support values, the value parameter 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 1.51. 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, i.e. how many dialogs were inserted into the profile
   with a specific value. If no value is passed, only the membersip of the
   dialog in the profile per se is checked. Note that if the profile does
   not support values, the value parameter 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 1.52. 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 1.53. 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 1.54. 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 1.55. dlg_resetflag usage
...
redlg_setflag("1");
...

6.8. dlg_bye(side)

   Send BYE to both parties of a dialog.

   Meaning of the parameters is as follows:
     * side - where to send the BYE. It can be: 'caller', 'callee', or
       both.

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

   Example 1.56. dlg_bye usage
...
dlg_bye("all");
...

6.9. dlg_refer(side, address)

   Refer the 'side' to a new SIP 'address'.

   Meaning of the parameters is as follows:
     * side - which side of the dialog to REFER. It can be: 'caller' or
       'callee'.
     * address - SIP address to refer to.

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

   Example 1.57. dlg_refer usage
...
dlg_refer("caller", "sip:announcement@kamailio.org");
...

6.10. dlg_manage()

   Process current SIP request with dialog module. It is an alternative to
   setting dialog flag for initial INVITE and Route-parameter-callback
   execution for within-dialog requests.

   This function can be used from REQUEST_ROUTE.

   Example 1.58. dlg_manage usage
...
modparam("dialog", "default_timeout", 100)
...
route {
...
    if(is_method("INVITE") && !has_totag())
    {
        $dlg_ctx(timeout_route) = 12;
        $dlg_ctx(timeout_bye) = 1;
    }
    dlg_manage();
...
}
...

6.11. dlg_bridge(from, to, op)

   Bridge 'from' SIP address to 'to' SIP address via outbound proxy 'op'.

   Meaning of the parameters is as follows:
     * from - SIP address of first side to call.
     * to - SIP address to refer "from" to.
     * op - outbound proxy SIP address.

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

   Example 1.59. dlg_bridge usage
...
dlg_bridge("sip:user@kamailio.org", "sip:annoucement@kamailio.org",
   "sip:kamailio.org:5080");
...

6.12. dlg_get(callid, ftag, ttag)

   Search and set current dialog based on Call-ID, From-Tag and To-Tag
   parameters.

   Meaning of the parameters is as follows:
     * callid - SIP call-id.
     * ftag - SIP From tag.
     * ttag - SIP To tag.

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

   Example 1.60. dlg_get usage
...
if(dlg_get("abcdef", "123", "456"))
{
        dlg_bye("all");
}
...

6.13. is_known_dlg()

   This function checks if the current SIP message being processed belongs
   to any transaction within an active dialog that the dialog module is
   currently tracking. This is a check for tracking of any kind, without
   regard to profiles.

   This function has numerous potential applications, among which is that
   it can be used to strengthen security for loose-routing sequential
   (in-dialog) requests or responses to them, as by providing a
   preventative check against spoofing on the proxy level instead of
   leaving the issue purely to the receiving UA.

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

   Example 1.61. is_known_dlg() usage
...
if(!uri == myself) {
        if(is_known_dlg()) {
                xlog("Request $rm from $ci is in-dialog\n");
        }
}
...

6.14. dlg_set_timeout(timeout [, h_entry, h_id])

   Set the dialog timeout. Dialog timeout will be updated if it was
   already set. If h_entry and h_id parameters are not provided, the
   dialog will be searched based on (callid, fromtag, totag) of currently
   processed SIP message.

   Meaning of the parameters is as follows:
     * timeout - the interval in seconds after which the dialog will time
       out.
     * h_entry - h_entry value of the iternal dialog identifier.
     * h_id - h_id valye if the internal dialog identifier.

   This function can be used from ANY_ROUTE.

   Example 1.62. dlg_set_timeout usage
...
if(dlg_set_timeout("180", "123", "456"))
{
    ...
}
...

6.15. dlg_set_timeout_by_profile(profile, [value], timeout)

   Like dlg_set_timeout(), but simultaneously sets the timeout of all
   dialogs in a given profile. Can be constrained by profile value.

   Meaning of the parameters is as follows:
     * profile - The dialog profile across which to apply the timeout.
       value (optional) - The profile value to use when applying the
       dialog timeout.
       timeout - the interval in seconds after which the dialog will time
       out.

   This function can be used from ANY_ROUTE.

   Example 1.63. dlg_set_timeout_by_profile usage
...
# All dialogs belonging to user abc123 (tracked via set_dlg_profile())
# will be timed out in 3 seconds.

dlg_set_timeout_by_profile("users", "abc123", "3");
...

6.16. dlg_set_property(attr)

   Set a dialog property - an attribute that enable/disable various
   behaviours (e.g., sending keep alive requests).

   Meaning of the parameters is as follows:
     * attr - name of property. It can be: 'ka-src' - send keep alive
       OPTION requests to caller; 'ka-dst' - send keep alive OPTION
       requests to callee.

   If keep alive is enabled for a dialog, the module will send SIP OPTIONS
   requests with CSeq lower or equal than last request within dialog, with
   the scope of detecting if the destination is still in the call. If the
   keep alive request results in a local timeout or '481 Call
   Leg/Transaction Does Not Exist', then the dialog is ended from the
   server.

   This function can be used from ANY_ROUTE.

   Example 1.64. dlg_set_property usage
...
dlg_set_property("ka-src");
dlg_set_property("ka-dst");
...

7. 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

   Returns the number of current active dialogs (may be confirmed or not).

7.2. early_dialogs

   Returns the number of early dialogs.

7.3. processed_dialogs

   Returns the total number of processed dialogs (terminated, expired or
   active) from the startup.

7.4. expired_dialogs

   Returns the total number of expired dialogs from the startup.

7.5. failed_dialogs

   Returns the number of 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

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).

   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

   The same as the "dlg_list" but including in the dialog description the
   associated context from modules sitting on top of the dialog module.

   Name: dlg_list_ctx

   Parameters: see "dlg_list"

   MI FIFO Command Format:
                :dlg_list_ctx:_reply_fifo_file_
                _empty_line_

8.3. dlg_end_dlg

   Terminates a confirmed dialog by sending BYE requests in both
   directions.

   Name: dlg_end_dlg

   Parameters:
     * h_entry - hash entry of the dialog in the internal dialog table
     * h_id - hash id of the dialog on the hash entry
     * extra_hdrs - (optional) string containg extra headers (full format)
       to be added to the BYE requests.

   The values for the h_entry and h_id can be get via the dlg_list MI
   command.

   Note: Works only for confirmed dialogs.

   MI FIFO Command Format:
                :dlg_end_dlg:_reply_fifo_file_
                342
                56
                _empty_line_

8.4. dlg_terminate_dlg

   Terminates a singe dialog, identified by a Call-ID.

   Name: dlg_terminate_dlg

   Parameters:
     * callid - callid of the dialog to be terminated.
     * from_tag (optional, but cannot be present without the callid
       parameter) - from tag (as per initial request) of the dialog to be
       terminated. 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.

   Note: Works only for confirmed dialogs.

   MI FIFO Command Format:
                :dlg_terminate_dlg:_reply_fifo_file_
                abcdrssfrs122444@192.168.1.1
                AAdfeEFF33

8.5. profile_get_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 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.

   Name: profile_get_size

   Parameters:
     * profile - name of the profile to get the value for.
     * value (optional)- string value to further restrict the check;

   MI FIFO Command Format:
                :profile_get_size:_reply_fifo_file_
                inbound_calls
                _empty_line_

8.6. profile_list_dlgs

   Lists all the dialogs belonging to a profile. If the profile supports
   values, the check can be reinforced to take into account a specific
   value - list only the dialogs that were inserted into the profile with
   that specific value. If no value is passed, all dialogs belonging to
   the profile will be listed. Note that if the profile does not supports
   values, this will be silently discarded.

   Name: profile_list_dlgs

   Parameters:
     * profile - name of the profile to list the dialog for.
     * value (optional)- string value to further restrict the check;

   MI FIFO Command Format:
                :profile_list_dlgs:_reply_fifo_file_
                inbound_calls
                _empty_line_

8.7. dlg_bridge

   Bridge two SIP addresses in a call using INVITE(hold)-REFER-BYE
   mechanism.

   Name: dlg_bridge

   Parameters:
     * from - SIP address to initiate the call
     * to - SIP address to refer 'from' to
     * op (optional) - outbound proxy SIP address

   MI FIFO Command Format:
                :dlg_bridge:_reply_fifo_file_
                from
                to
                op
                _empty_line_

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

   Lists the description of all dialogs (calls).

   Name: dlg.list

   RPC Command Format:
                serctl dlg_list

9.2. dlg.list_ctx

   The same as the "dlg_list" but including in the dialog description the
   associated context from modules sitting on top of the dialog module.

   Name: dlg.list_ctx

   RPC Command Format:
                serctl dlg.list_ctx

9.3. dlg.dlg_list

   Lists the description of one dialog. The dialog identifiers are to be
   passed as parameter (callid and fromtag).

   Name: dlg.dlg_list

   Parameters:
     * callid callid of the dialog to be listed.
     * from_tag from tag (as per initial request) of the dialog to be
       listed.

   RPC Command Format:
                serctl dlg.list abcdrssfrs122444@192.168.1.1 AAdfeEFF33

9.4. dlg.dlg_list_ctx

   The same as the "dlg.list_ctx" but including in the dialog description
   the associated context from modules sitting on top of the dialog
   module.

   Name: dlg.dlg_list_ctx

   Parameters: see "dlg_list"

   RPC Command Format:
                serctl dlg.list_ctx abcdrssfrs122444@192.168.1.1 AAdfeEFF33

9.5. dlg.end_dlg

   Terminates an ongoing dialog by sending BYE in both directions.

   Name: dlg.end_dlg

   Parameters:
     * h_entry - hash entry of the dialog in the internal dialog table
     * h_id - hash id of the dialog on the hash entry
     * extra_hdrs - (optional) string containg extra headers (full format)
       to be added to the BYE requests.

   The values for the h_entry and h_id can be get via the dlg_list RPC
   command.

   RPC Command Format:
                serctl dlg.end_dlg 342 56

9.6. dlg.profile_get_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 the simply belonging of the
   dialog to the profile is checked. Note that if the profile does not
   support values, the value parameter will be silently discarded.

   Name: dlg.profile_get_size

   Parameters:
     * profile - name of the profile to get the value for.
     * value (optional)- string value to further restrict the check;

   RPC Command Format:
                serctl dlg.dlg.profile_get_size inbound_calls

9.7. dlg.profile_list

   Lists all the dialogs belonging to a profile. If the profile supports
   values, the check can be reinforced to take into account a specific
   value, i.e. list only the dialogs that were inserted into the profile
   with that specific value. If no value is passed, all dialogs belonging
   to the profile will be listed. Note that if the profile does not
   supports values, this will be silently discarded.

   Name: dlg.profile_list

   Parameters:
     * profile - name of the profile to list the dialog for.
     * value (optional)- string value to further restrict the check;

   RPC Command Format:
                serctl dlg.profile_list inbound_calls

9.8. dlg.bridge_dlg

   Bridge two SIP addresses into a call using INVITE(hold)-REFER-BYE
   mechanism.

   Name: dlg.bridge_dlg

   Parameters:
     * from - SIP address to initiate the call
     * to - SIP address to refer 'from' to
     * op (optional) - outbound proxy SIP address

   RPC Command Format:
                serctl dlg.list from to op

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

   Returns the number of current active dialogs (may be confirmed or not).

10.2. $DLG_status

   Returns the status of the dialog corresponding to the processed
   sequential request. This PV will be available only for sequential
   requests, after doing loose_route().

   Value may be:
     * NULL - Dialog not found.
     * 3 - Confirmed by a final reply but no ACK received yet.
     * 4 - Confirmed by a final reply and ACK received.
     * 5 - Dialog ended.

10.3. $DLG_lifetime

   Returns the duration (in seconds) of the dialog corresponding to the
   processed sequential request. The duration is calculated from the
   dialog confirmation and the current moment. This PV will be available
   only for sequential requests, after doing loose_route().

   NULL will be returned if there is no dialog for the request.

10.4. $dlg(...)

   Access to dialog attributes.

10.5. $dlg_ctx(...)

   Access to dialog context attributes.

10.6. $dlg_var(key)

   This is a read/write variable that can be used to store custom values
   assigned with a dialog (e.g. the URI of a billing-server, an assigned
   emergency-server). This pseudo-variable will be available only for
   subsequential requests after doing loose_route().

   Note: You will receive "NULL", if there is no dialog for this request.

11. Event Routes

   11.1. event_route[dialog:start]
   11.2. event_route[dialog:end]
   11.3. event_route[dialog:failed]

11.1. event_route[dialog:start]

   Executed when 200OK for INVITE is processed.

11.2. event_route[dialog:end]

   Executed when BYE is processed or dialog timed out.

11.3. event_route[dialog:failed]

   Executed when dialog is not completed (+300 reply to INVITE).

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 (dlg, hdrs)

1. Available Functions

   1.1. register_dlgcb (dialog, type, cb, param, free_param_cb)
   1.2. terminate_dlg (dlg, hdrs)

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 (dlg, hdrs)

   Terminate a Dialog

   Meaning of parameters is as follows:
     * struct dlg_cell* dlg - dialog to terminate.
     * str* hdrs - string containg extra headers (full format) to be added
       to the BYE requests of the dialog.

Chapter 3. Frequently Asked Questions

   3.1. What happend with "use_tight_match" parameter?
   3.2. Where can I find more about Kamailio?
   3.3. Where can I post a question about this module?
   3.4. 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.

   Where can I find more about Kamailio?

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

   3.3.

   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>.

   3.4.

   How can I report a bug?

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