app_confbridge: Add a regcontext option for confbridge bridge profiles.

This patch allows for having app_confbridge register the name of the
conference as an extension into a specific context, similar to
regcontext for chan_sip.  This variant is not quite as involved as the
one in chan_sip and doesn't allow for multiple contexts or custom
extensions, you can only specify the context and the conference name
will always be used as the extension to register.

ASTERISK-25989 #close

Change-Id: Icacf94d9f2b5dfd31ef36f6cb702392619a7902f

CHANGES

@@ -284,6 +284,14 @@ res_pjsip
    into the "reg_server" field in the ps_contacts table to facilitate
    multi-server setups.
 
+app_confbridge
+------------------
+ * Added a bridge profile option called regcontext that allows you to
+   dynamically register the conference bridge name as an extension into
+   the specified context.  This allows tracking down conferences on multi-
+   server installations via alternate means (DUNDI for example). By default
+   this feature is not used.
+
 ------------------------------------------------------------------------------
 --- Functionality changes from Asterisk 13.8.0 to Asterisk 13.9.0 ------------
 ------------------------------------------------------------------------------

apps/app_confbridge.c

@@ -1256,9 +1256,17 @@ void conf_handle_second_active(struct confbridge_conference *conference)
 
 void conf_ended(struct confbridge_conference *conference)
 {
+	struct pbx_find_info q = { .stacklen = 0 };
+
 	/* Called with a reference to conference */
 	ao2_unlink(conference_bridges, conference);
 	send_conf_end_event(conference);
+	if (!ast_strlen_zero(conference->b_profile.regcontext) &&
+			pbx_find_extension(NULL, NULL, &q, conference->b_profile.regcontext,
+				conference->name, 1, NULL, "", E_MATCH)) {
+		ast_context_remove_extension(conference->b_profile.regcontext,
+				conference->name, 1, NULL);
+	}
 	ao2_lock(conference);
 	conf_stop_record(conference);
 	ao2_unlock(conference);
@@ -1363,6 +1371,13 @@ static struct confbridge_conference *join_conference_bridge(const char *conferen
 		}
 
 		send_conf_start_event(conference);
+
+		if (!ast_strlen_zero(conference->b_profile.regcontext)) {
+			if (!ast_exists_extension(NULL, conference->b_profile.regcontext, conference->name, 1, NULL)) {
+				ast_add_extension(conference->b_profile.regcontext, 1, conference->name, 1, NULL, NULL, "Noop", NULL, NULL, "ConfBridge");
+			}
+		}
+
 		ast_debug(1, "Created conference '%s' and linked to container.\n", conference_name);
 	}
 

apps/confbridge/conf_config_parser.c

@@ -339,6 +339,22 @@ ASTERISK_REGISTER_FILE()
 						unescaped to <variable>X</variable>. All variables will be evaluated at the time ConfBridge is called.
 					</para></description>
 				</configOption>
+				<configOption name="regcontext">
+					<synopsis>The name of the context into which to register the name of the conference bridge as NoOP() at priority 1</synopsis>
+					<description><para>
+						When set this will cause the name of the created conference to be registered
+						into the named context at priority 1 with an operation of NoOP().  This can
+						then be used in other parts of the dialplan to test for the existence of a
+						specific conference bridge.
+						You should be aware that there are potential races between testing for the
+						existence of a bridge, and taking action upon that information, consider
+						for example two callers executing the check simultaniously, and then taking
+						special action as "first caller" into the bridge.  The same for exiting,
+						directly after the check the bridge can be destroyed before the new caller
+						enters (creating a new bridge), for example, and the "first member" actions
+						could thus be missed.
+					</para></description>
+				</configOption>
 				<configOption name="video_mode">
 					<synopsis>Sets how confbridge handles video distribution to the conference participants</synopsis>
 					<description><para>
@@ -1595,6 +1611,8 @@ static char *handle_cli_confbridge_show_bridge_profile(struct ast_cli_entry *e,
 		ast_cli(a->fd,"Max Members:          No Limit\n");
 	}
 
+	ast_cli(a->fd,"Registration context: %s\n", b_profile.regcontext);
+
 	switch (b_profile.flags
 		& (BRIDGE_OPT_VIDEO_SRC_LAST_MARKED | BRIDGE_OPT_VIDEO_SRC_FIRST_MARKED
 			| BRIDGE_OPT_VIDEO_SRC_FOLLOW_TALKER)) {
@@ -2163,6 +2181,7 @@ int conf_load_config(void)
 	aco_option_register(&cfg_info, "record_file", ACO_EXACT, bridge_types, NULL, OPT_CHAR_ARRAY_T, 0, CHARFLDSET(struct bridge_profile, rec_file));
 	aco_option_register(&cfg_info, "record_options", ACO_EXACT, bridge_types, NULL, OPT_CHAR_ARRAY_T, 0, CHARFLDSET(struct bridge_profile, rec_options));
 	aco_option_register(&cfg_info, "record_command", ACO_EXACT, bridge_types, NULL, OPT_CHAR_ARRAY_T, 0, CHARFLDSET(struct bridge_profile, rec_command));
+	aco_option_register(&cfg_info, "regcontext", ACO_EXACT, bridge_types, NULL, OPT_CHAR_ARRAY_T, 0, CHARFLDSET(struct bridge_profile, regcontext));
 	aco_option_register(&cfg_info, "language", ACO_EXACT, bridge_types, "en", OPT_CHAR_ARRAY_T, 0, CHARFLDSET(struct bridge_profile, language));
 	aco_option_register_custom(&cfg_info, "^sound_", ACO_REGEX, bridge_types, NULL, sound_option_handler, 0);
 	/* This option should only be used with the CONFBRIDGE dialplan function */

apps/confbridge/include/confbridge.h

@@ -210,6 +210,7 @@ struct bridge_profile {
 	unsigned int internal_sample_rate; /*!< The internal sample rate of the bridge. 0 when set to auto adjust mode. */
 	unsigned int mix_interval;  /*!< The internal mixing interval used by the bridge. When set to 0 the bridgewill use a default interval. */
 	struct bridge_profile_sounds *sounds;
+	char regcontext[AST_MAX_CONTEXT];
 };
 
 /*! \brief The structure that represents a conference bridge */

configs/samples/confbridge.conf.sample

@@ -217,6 +217,8 @@ type=bridge
 ;language=en               ; Set the language used for announcements to the conference.
                            ; Default is en (English).
 
+;regcontext=conferences    ; The name of the context into which to register conference names as extensions.
+
 ; All sounds in the conference are customizable using the bridge profile options below.
 ; Simply state the option followed by the filename or full path of the filename after
 ; the option.  Example: sound_had_joined=conf-hasjoin  This will play the conf-hasjoin