From 806946c35cf0560248e63fea53c4d82426a2034a Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Timo=20Ter=C3=A4s?= <timo.teras@iki.fi>
Date: Wed, 5 Sep 2012 10:07:05 +0300
Subject: [PATCH] ASTERISK-19109: Implement deaf participant support for
 ConfBridge

---
 CHANGES                                |   3 +
 apps/app_confbridge.c                  | 218 ++++++++++++++++++++++++++++++---
 apps/confbridge/conf_config_parser.c   |  14 +++
 apps/confbridge/include/confbridge.h   |   6 +
 bridges/bridge_multiplexed.c           |   2 +-
 bridges/bridge_simple.c                |   2 +-
 bridges/bridge_softmix.c               |  38 +++---
 configs/confbridge.conf.sample         |   5 +
 include/asterisk/bridging_features.h   |   2 +
 include/asterisk/bridging_technology.h |  15 +++
 main/bridging.c                        |  22 ++++
 11 files changed, 294 insertions(+), 33 deletions(-)

diff --git a/CHANGES b/CHANGES
index c3c9891..2efa17b 100644
--- a/CHANGES
+++ b/CHANGES
@@ -66,6 +66,9 @@ ConfBridge
    file will be played to the user, and only the user, upon joining the
    conference bridge.
 
+ * Added support for deaf participants with CLI commands, manager actions
+   and ConfBridge DTMF actions to toggle the deaf state.
+
 
 Dial
 -------------------
diff --git a/apps/app_confbridge.c b/apps/app_confbridge.c
index 90954b8..0455be4 100644
--- a/apps/app_confbridge.c
+++ b/apps/app_confbridge.c
@@ -185,6 +185,30 @@ ASTERISK_FILE_VERSION(__FILE__, "$Revision$")
 		<description>
 		</description>
 	</manager>
+	<manager name="ConfbridgeDeafen" language="en_US">
+		<synopsis>
+			Deafen a Confbridge user.
+		</synopsis>
+		<syntax>
+			<xi:include xpointer="xpointer(/docs/manager[@name='Login']/syntax/parameter[@name='ActionID'])" />
+			<parameter name="Conference" required="true" />
+			<parameter name="Channel" required="true" />
+		</syntax>
+		<description>
+		</description>
+	</manager>
+	<manager name="ConfbridgeUndeafen" language="en_US">
+		<synopsis>
+			Undeafen a Confbridge user.
+		</synopsis>
+		<syntax>
+			<xi:include xpointer="xpointer(/docs/manager[@name='Login']/syntax/parameter[@name='ActionID'])" />
+			<parameter name="Conference" required="true" />
+			<parameter name="Channel" required="true" />
+		</syntax>
+		<description>
+		</description>
+	</manager>
 	<manager name="ConfbridgeKick" language="en_US">
 		<synopsis>
 			Kick a Confbridge user.
@@ -273,6 +297,13 @@ static const char app[] = "ConfBridge";
 /* Number of buckets our conference bridges container can have */
 #define CONFERENCE_BRIDGE_BUCKETS 53
 
+enum confbridge_feature_action {
+	CONFBRIDGE_FEATURE_MUTE,
+	CONFBRIDGE_FEATURE_UNMUTE,
+	CONFBRIDGE_FEATURE_DEAFEN,
+	CONFBRIDGE_FEATURE_UNDEAFEN
+};
+
 /*! \brief Container to hold all conference bridges in progress */
 static struct ao2_container *conference_bridges;
 
@@ -311,6 +342,10 @@ const char *conf_get_sound(enum conf_sounds sound, struct bridge_profile_sounds
 		return S_OR(custom_sounds->muted, "conf-muted");
 	case CONF_SOUND_UNMUTED:
 		return S_OR(custom_sounds->unmuted, "conf-unmuted");
+	case CONF_SOUND_DEAFENED:
+		return S_OR(custom_sounds->deafened, "conf-deafened");
+	case CONF_SOUND_UNDEAFENED:
+		return S_OR(custom_sounds->undeafened, "conf-undeafened");
 	case CONF_SOUND_ONLY_ONE:
 		return S_OR(custom_sounds->onlyone, "conf-onlyone");
 	case CONF_SOUND_THERE_ARE:
@@ -1504,10 +1539,13 @@ static int confbridge_exec(struct ast_channel *chan, const char *data)
 	volume_adjustments[0] = ast_audiohook_volume_get(chan, AST_AUDIOHOOK_DIRECTION_READ);
 	volume_adjustments[1] = ast_audiohook_volume_get(chan, AST_AUDIOHOOK_DIRECTION_WRITE);
 
-	/* If the caller should be joined already muted, make it so */
+	/* If the caller should be joined already muted or deaf, make it so */
 	if (ast_test_flag(&conference_bridge_user.u_profile, USER_OPT_STARTMUTED)) {
 		conference_bridge_user.features.mute = 1;
 	}
+	if (ast_test_flag(&conference_bridge_user.u_profile, USER_OPT_STARTDEAF)) {
+		conference_bridge_user.features.deaf = 1;
+	}
 
 	if (ast_test_flag(&conference_bridge_user.u_profile, USER_OPT_DROP_SILENCE)) {
 		conference_bridge_user.tech_args.drop_silence = 1;
@@ -1668,6 +1706,20 @@ static int action_toggle_mute_participants(struct conference_bridge *conference_
 	return 0;
 }
 
+static int action_toggle_deaf(struct conference_bridge *conference_bridge,
+	struct conference_bridge_user *conference_bridge_user,
+	struct ast_channel *chan)
+{
+	/* Deafen or undeafen yourself */
+	conference_bridge_user->features.deaf = (!conference_bridge_user->features.deaf ? 1 : 0);
+	ast_test_suite_event_notify("CONF_DEAF", "Message: participant %s %s\r\nConference: %s\r\nChannel: %s", chan->name, conference_bridge_user->features.deaf ? "deafened" : "undeafened", conference_bridge_user->b_profile.name, chan->name);
+
+	return ast_stream_and_wait(chan, (conference_bridge_user->features.deaf ?
+		conf_get_sound(CONF_SOUND_DEAFENED, conference_bridge_user->b_profile.sounds) :
+		conf_get_sound(CONF_SOUND_UNDEAFENED, conference_bridge_user->b_profile.sounds)),
+		"");
+}
+
 static int action_playback(struct ast_bridge_channel *bridge_channel, const char *playback_file)
 {
 	char *file_copy = ast_strdupa(playback_file);
@@ -1856,6 +1908,11 @@ static int execute_menu_entry(struct conference_bridge *conference_bridge,
 		case MENU_ACTION_PARTICIPANT_COUNT:
 			announce_user_count(conference_bridge, conference_bridge_user);
 			break;
+		case MENU_ACTION_TOGGLE_DEAF:
+			res |= action_toggle_deaf(conference_bridge,
+				conference_bridge_user,
+				bridge_channel->chan);
+			break;
 		case MENU_ACTION_PLAYBACK:
 			if (!stop_prompts) {
 				res |= action_playback(bridge_channel, menu_action->data.playback_file);
@@ -2119,13 +2176,13 @@ static int generic_lock_unlock_helper(int lock, const char *conference)
 }
 
 /* \internal
- * \brief finds a conference user by channel name and mutes/unmutes them.
+ * \brief finds a conference user by channel name and changes feature bits on it.
  *
  * \retval 0 success
  * \retval -1 conference not found
  * \retval -2 user not found
  */
-static int generic_mute_unmute_helper(int mute, const char *conference, const char *user)
+static int generic_feature_action_helper(enum confbridge_feature_action action, const char *conference, const char *user)
 {
 	struct conference_bridge *bridge = NULL;
 	struct conference_bridge tmp;
@@ -2143,10 +2200,44 @@ static int generic_mute_unmute_helper(int mute, const char *conference, const ch
 		}
 	}
 	if (participant) {
-		participant->features.mute = mute;
-		ast_test_suite_event_notify("CONF_MUTE", "Message: participant %s %s\r\nConference: %s\r\nChannel: %s", ast_channel_name(participant->chan), participant->features.mute ? "muted" : "unmuted", bridge->b_profile.name, ast_channel_name(participant->chan));
+		const char *state, *verb;
+
+		switch (action) {
+		case CONFBRIDGE_FEATURE_DEAFEN:
+			participant->features.deaf = 1;
+			state = "CONF_DEAF";
+			verb = "deafened";
+			break;
+		case CONFBRIDGE_FEATURE_UNDEAFEN:
+			participant->features.deaf = 0;
+			state = "CONF_DEAF";
+			verb = "undeafened";
+			break;
+		case CONFBRIDGE_FEATURE_MUTE:
+			participant->features.mute = 1;
+			state = "CONF_MUTE";
+			verb = "muted";
+			break;
+		case CONFBRIDGE_FEATURE_UNMUTE:
+		default:
+			participant->features.mute = 0;
+			state = "CONF_MUTE";
+			verb = "unmuted";
+			break;
+		}
+
+		if (state != NULL && verb != NULL) {
+			ast_test_suite_event_notify(state,
+				"Message: participant %s %s\r\n"
+				"Conference: %s\r\n"
+				"Channel: %s",
+				ast_channel_name(participant->chan),
+				verb,
+				bridge->b_profile.name,
+				ast_channel_name(participant->chan));
+		}
 	} else {
-		res = -2;;
+		res = -2;
 	}
 	ao2_unlock(bridge);
 	ao2_ref(bridge, -1);
@@ -2154,9 +2245,10 @@ static int generic_mute_unmute_helper(int mute, const char *conference, const ch
 	return res;
 }
 
-static int cli_mute_unmute_helper(int mute, struct ast_cli_args *a)
+static int cli_feature_action_helper(enum confbridge_feature_action action, struct ast_cli_args *a)
 {
-	int res = generic_mute_unmute_helper(mute, a->argv[2], a->argv[3]);
+	const char *verb;
+	int res = generic_feature_action_helper(action, a->argv[2], a->argv[3]);
 
 	if (res == -1) {
 		ast_cli(a->fd, "No conference bridge named '%s' found!\n", a->argv[2]);
@@ -2165,7 +2257,24 @@ static int cli_mute_unmute_helper(int mute, struct ast_cli_args *a)
 		ast_cli(a->fd, "No channel named '%s' found in conference %s\n", a->argv[3], a->argv[2]);
 		return -1;
 	}
-	ast_cli(a->fd, "%s %s from confbridge %s\n", mute ? "Muting" : "Unmuting", a->argv[3], a->argv[2]);
+
+	switch (action) {
+	case CONFBRIDGE_FEATURE_DEAFEN:
+		verb = "Deafening";
+		break;
+	case CONFBRIDGE_FEATURE_UNDEAFEN:
+		verb = "Undeafening";
+		break;
+	case CONFBRIDGE_FEATURE_MUTE:
+		verb = "Muting";
+		break;
+	case CONFBRIDGE_FEATURE_UNMUTE:
+	default:
+		verb = "Unmuting";
+		break;
+	}
+
+	ast_cli(a->fd, "%s %s from confbridge %s\n", verb, a->argv[3], a->argv[2]);
 	return 0;
 }
 
@@ -2187,7 +2296,7 @@ static char *handle_cli_confbridge_mute(struct ast_cli_entry *e, int cmd, struct
 		return CLI_SHOWUSAGE;
 	}
 
-	cli_mute_unmute_helper(1, a);
+	cli_feature_action_helper(CONFBRIDGE_FEATURE_MUTE, a);
 
 	return CLI_SUCCESS;
 }
@@ -2210,7 +2319,53 @@ static char *handle_cli_confbridge_unmute(struct ast_cli_entry *e, int cmd, stru
 		return CLI_SHOWUSAGE;
 	}
 
-	cli_mute_unmute_helper(0, a);
+	cli_feature_action_helper(CONFBRIDGE_FEATURE_UNMUTE, a);
+
+	return CLI_SUCCESS;
+}
+
+static char *handle_cli_confbridge_deafen(struct ast_cli_entry *e, int cmd, struct ast_cli_args *a)
+{
+	switch (cmd) {
+	case CLI_INIT:
+		e->command = "confbridge deafen";
+		e->usage =
+			"Usage: confbridge deafen <conference> <channel>\n";
+		return NULL;
+	case CLI_GENERATE:
+		if (a->pos == 2) {
+			return complete_confbridge_name(a->line, a->word, a->pos, a->n);
+		}
+		return NULL;
+	}
+	if (a->argc != 4) {
+		return CLI_SHOWUSAGE;
+	}
+
+	cli_feature_action_helper(CONFBRIDGE_FEATURE_DEAFEN, a);
+
+	return CLI_SUCCESS;
+}
+
+static char *handle_cli_confbridge_undeafen(struct ast_cli_entry *e, int cmd, struct ast_cli_args *a)
+{
+	switch (cmd) {
+	case CLI_INIT:
+		e->command = "confbridge undeafen";
+		e->usage =
+			"Usage: confbridge undeafen <conference> <channel>\n";
+		return NULL;
+	case CLI_GENERATE:
+		if (a->pos == 2) {
+			return complete_confbridge_name(a->line, a->word, a->pos, a->n);
+		}
+		return NULL;
+	}
+	if (a->argc != 4) {
+		return CLI_SHOWUSAGE;
+	}
+
+	cli_feature_action_helper(CONFBRIDGE_FEATURE_UNDEAFEN, a);
 
 	return CLI_SUCCESS;
 }
@@ -2358,6 +2513,8 @@ static struct ast_cli_entry cli_confbridge[] = {
 	AST_CLI_DEFINE(handle_cli_confbridge_kick, "Kick participants out of conference bridges."),
 	AST_CLI_DEFINE(handle_cli_confbridge_mute, "Mute a participant."),
 	AST_CLI_DEFINE(handle_cli_confbridge_unmute, "Unmute a participant."),
+	AST_CLI_DEFINE(handle_cli_confbridge_deafen, "Deafen a participant."),
+	AST_CLI_DEFINE(handle_cli_confbridge_undeafen, "Undeafen a participant."),
 	AST_CLI_DEFINE(handle_cli_confbridge_lock, "Lock a conference."),
 	AST_CLI_DEFINE(handle_cli_confbridge_unlock, "Unlock a conference."),
 	AST_CLI_DEFINE(handle_cli_confbridge_start_record, "Start recording a conference"),
@@ -2492,10 +2649,11 @@ static int action_confbridgelistrooms(struct mansession *s, const struct message
 	return 0;
 }
 
-static int action_mute_unmute_helper(struct mansession *s, const struct message *m, int mute)
+static int action_feature_action_helper(struct mansession *s, const struct message *m, enum confbridge_feature_action action)
 {
 	const char *conference = astman_get_header(m, "Conference");
 	const char *channel = astman_get_header(m, "Channel");
+	char *verb;
 	int res = 0;
 
 	if (ast_strlen_zero(conference)) {
@@ -2511,7 +2669,7 @@ static int action_mute_unmute_helper(struct mansession *s, const struct message
 		return 0;
 	}
 
-	res = generic_mute_unmute_helper(mute, conference, channel);
+	res = generic_feature_action_helper(action, conference, channel);
 
 	if (res == -1) {
 		astman_send_error(s, m, "No Conference by that name found.");
@@ -2521,17 +2679,41 @@ static int action_mute_unmute_helper(struct mansession *s, const struct message
 		return 0;
 	}
 
-	astman_send_ack(s, m, mute ? "User muted" : "User unmuted");
+	switch (action) {
+	case CONFBRIDGE_FEATURE_DEAFEN:
+		verb = "User deafened";
+		break;
+	case CONFBRIDGE_FEATURE_UNDEAFEN:
+		verb = "User undeafened";
+		break;
+	case CONFBRIDGE_FEATURE_MUTE:
+		verb = "User muted";
+		break;
+	case CONFBRIDGE_FEATURE_UNMUTE:
+	default:
+		verb = "User unmuted";
+		break;
+	}
+
+	astman_send_ack(s, m, verb);
 	return 0;
 }
 
 static int action_confbridgeunmute(struct mansession *s, const struct message *m)
 {
-	return action_mute_unmute_helper(s, m, 0);
+	return action_feature_action_helper(s, m, CONFBRIDGE_FEATURE_UNMUTE);
 }
 static int action_confbridgemute(struct mansession *s, const struct message *m)
 {
-	return action_mute_unmute_helper(s, m, 1);
+	return action_feature_action_helper(s, m, CONFBRIDGE_FEATURE_MUTE);
+}
+static int action_confbridgeundeafen(struct mansession *s, const struct message *m)
+{
+	return action_feature_action_helper(s, m, CONFBRIDGE_FEATURE_UNDEAFEN);
+}
+static int action_confbridgedeafen(struct mansession *s, const struct message *m)
+{
+	return action_feature_action_helper(s, m, CONFBRIDGE_FEATURE_DEAFEN);
 }
 
 static int action_lock_unlock_helper(struct mansession *s, const struct message *m, int lock)
@@ -2818,6 +3000,8 @@ static int unload_module(void)
 	res |= ast_manager_unregister("ConfbridgeListRooms");
 	res |= ast_manager_unregister("ConfbridgeMute");
 	res |= ast_manager_unregister("ConfbridgeUnmute");
+	res |= ast_manager_unregister("ConfbridgeDeafen");
+	res |= ast_manager_unregister("ConfbridgeUndeafen");
 	res |= ast_manager_unregister("ConfbridgeKick");
 	res |= ast_manager_unregister("ConfbridgeUnlock");
 	res |= ast_manager_unregister("ConfbridgeLock");
@@ -2860,6 +3044,8 @@ static int load_module(void)
 	res |= ast_manager_register_xml("ConfbridgeListRooms", EVENT_FLAG_REPORTING, action_confbridgelistrooms);
 	res |= ast_manager_register_xml("ConfbridgeMute", EVENT_FLAG_CALL, action_confbridgemute);
 	res |= ast_manager_register_xml("ConfbridgeUnmute", EVENT_FLAG_CALL, action_confbridgeunmute);
+	res |= ast_manager_register_xml("ConfbridgeDeafen", EVENT_FLAG_CALL, action_confbridgedeafen);
+	res |= ast_manager_register_xml("ConfbridgeUndeafen", EVENT_FLAG_CALL, action_confbridgeundeafen);
 	res |= ast_manager_register_xml("ConfbridgeKick", EVENT_FLAG_CALL, action_confbridgekick);
 	res |= ast_manager_register_xml("ConfbridgeUnlock", EVENT_FLAG_CALL, action_confbridgeunlock);
 	res |= ast_manager_register_xml("ConfbridgeLock", EVENT_FLAG_CALL, action_confbridgelock);
diff --git a/apps/confbridge/conf_config_parser.c b/apps/confbridge/conf_config_parser.c
index f4a9604..8a02de7 100644
--- a/apps/confbridge/conf_config_parser.c
+++ b/apps/confbridge/conf_config_parser.c
@@ -279,6 +279,10 @@ static int set_sound(const char *sound_name, const char *sound_file, struct brid
 		ast_string_field_set(sounds, muted, sound_file);
 	} else if (!strcasecmp(sound_name, "sound_unmuted")) {
 		ast_string_field_set(sounds, unmuted, sound_file);
+	} else if (!strcasecmp(sound_name, "sound_deafened")) {
+		ast_string_field_set(sounds, deafened, sound_file);
+	} else if (!strcasecmp(sound_name, "sound_undeafened")) {
+		ast_string_field_set(sounds, undeafened, sound_file);
 	} else if (!strcasecmp(sound_name, "sound_there_are")) {
 		ast_string_field_set(sounds, thereare, sound_file);
 	} else if (!strcasecmp(sound_name, "sound_other_in_party")) {
@@ -418,6 +422,7 @@ static int add_action_to_menu_entry(struct conf_menu_entry *menu_entry, enum con
 	switch (id) {
 	case MENU_ACTION_NOOP:
 	case MENU_ACTION_TOGGLE_MUTE:
+	case MENU_ACTION_TOGGLE_DEAF:
 	case MENU_ACTION_INCREASE_LISTENING:
 	case MENU_ACTION_DECREASE_LISTENING:
 	case MENU_ACTION_INCREASE_TALKING:
@@ -708,6 +713,9 @@ static char *handle_cli_confbridge_show_user_profile(struct ast_cli_entry *e, in
 	ast_cli(a->fd,"Start Muted:             %s\n",
 		u_profile.flags & USER_OPT_STARTMUTED?
 		"true" : "false");
+	ast_cli(a->fd,"Start Deaf:              %s\n",
+		u_profile.flags & USER_OPT_STARTDEAF?
+		"true" : "false");
 	ast_cli(a->fd,"MOH When Empty:          %s\n",
 		u_profile.flags & USER_OPT_MUSICONHOLD ?
 		"enabled" : "disabled");
@@ -896,6 +904,8 @@ static char *handle_cli_confbridge_show_bridge_profile(struct ast_cli_entry *e,
 	ast_cli(a->fd,"sound_kicked:         %s\n", conf_get_sound(CONF_SOUND_KICKED, b_profile.sounds));
 	ast_cli(a->fd,"sound_muted:          %s\n", conf_get_sound(CONF_SOUND_MUTED, b_profile.sounds));
 	ast_cli(a->fd,"sound_unmuted:        %s\n", conf_get_sound(CONF_SOUND_UNMUTED, b_profile.sounds));
+	ast_cli(a->fd,"sound_deafened:       %s\n", conf_get_sound(CONF_SOUND_DEAFENED, b_profile.sounds));
+	ast_cli(a->fd,"sound_undeafened:     %s\n", conf_get_sound(CONF_SOUND_UNDEAFENED, b_profile.sounds));
 	ast_cli(a->fd,"sound_there_are:      %s\n", conf_get_sound(CONF_SOUND_THERE_ARE, b_profile.sounds));
 	ast_cli(a->fd,"sound_other_in_party: %s\n", conf_get_sound(CONF_SOUND_OTHER_IN_PARTY, b_profile.sounds));
 	ast_cli(a->fd,"sound_place_into_conference: %s\n", conf_get_sound(CONF_SOUND_PLACE_IN_CONF, b_profile.sounds));
@@ -1021,6 +1031,9 @@ static char *handle_cli_confbridge_show_menu(struct ast_cli_entry *e, int cmd, s
 			case MENU_ACTION_TOGGLE_MUTE:
 				ast_cli(a->fd, "toggle_mute");
 				break;
+			case MENU_ACTION_TOGGLE_DEAF:
+				ast_cli(a->fd, "toggle_deaf");
+				break;
 			case MENU_ACTION_NOOP:
 				ast_cli(a->fd, "no_op");
 				break;
@@ -1268,6 +1281,7 @@ int conf_load_config(int reload)
 	aco_option_register(&cfg_info, "admin", ACO_EXACT, user_types, "no", OPT_BOOLFLAG_T, 1, FLDSET(struct user_profile, flags), USER_OPT_ADMIN);
 	aco_option_register(&cfg_info, "marked", ACO_EXACT, user_types, "no", OPT_BOOLFLAG_T, 1, FLDSET(struct user_profile, flags), USER_OPT_MARKEDUSER);
 	aco_option_register(&cfg_info, "startmuted", ACO_EXACT, user_types, "no", OPT_BOOLFLAG_T, 1, FLDSET(struct user_profile, flags), USER_OPT_STARTMUTED);
+	aco_option_register(&cfg_info, "startdeaf", ACO_EXACT, user_types, "no", OPT_BOOLFLAG_T, 1, FLDSET(struct user_profile, flags), USER_OPT_STARTDEAF);
 	aco_option_register(&cfg_info, "music_on_hold_when_empty", ACO_EXACT, user_types, "no", OPT_BOOLFLAG_T, 1, FLDSET(struct user_profile, flags), USER_OPT_MUSICONHOLD);
 	aco_option_register(&cfg_info, "quiet", ACO_EXACT, user_types, "no", OPT_BOOLFLAG_T, 1, FLDSET(struct user_profile, flags), USER_OPT_QUIET);
 	aco_option_register_custom(&cfg_info, "announce_user_count_all", ACO_EXACT, user_types, "no", announce_user_count_all_handler, 0);
diff --git a/apps/confbridge/include/confbridge.h b/apps/confbridge/include/confbridge.h
index d3ead35..3d773c5 100644
--- a/apps/confbridge/include/confbridge.h
+++ b/apps/confbridge/include/confbridge.h
@@ -57,6 +57,7 @@ enum user_profile_flags {
 	USER_OPT_DTMF_PASS    =  (1 << 13), /*!< Sets if dtmf should be passed into the conference or not */
 	USER_OPT_ANNOUNCEUSERCOUNTALL = (1 << 14), /*!< Sets if the number of users should be announced to everyone. */
 	USER_OPT_JITTERBUFFER =  (1 << 15), /*!< Places a jitterbuffer on the user. */
+	USER_OPT_STARTDEAF =     (1 << 16), /*!< Set if the caller should be initially set deaf */
 };
 
 enum bridge_profile_flags {
@@ -68,6 +69,7 @@ enum bridge_profile_flags {
 
 enum conf_menu_action_id {
 	MENU_ACTION_TOGGLE_MUTE = 1,
+	MENU_ACTION_TOGGLE_DEAF,
 	MENU_ACTION_PLAYBACK,
 	MENU_ACTION_PLAYBACK_AND_CONTINUE,
 	MENU_ACTION_INCREASE_LISTENING,
@@ -142,6 +144,8 @@ enum conf_sounds {
 	CONF_SOUND_KICKED,
 	CONF_SOUND_MUTED,
 	CONF_SOUND_UNMUTED,
+	CONF_SOUND_DEAFENED,
+	CONF_SOUND_UNDEAFENED,
 	CONF_SOUND_ONLY_ONE,
 	CONF_SOUND_THERE_ARE,
 	CONF_SOUND_OTHER_IN_PARTY,
@@ -168,6 +172,8 @@ struct bridge_profile_sounds {
 		AST_STRING_FIELD(kicked);
 		AST_STRING_FIELD(muted);
 		AST_STRING_FIELD(unmuted);
+		AST_STRING_FIELD(deafened);
+		AST_STRING_FIELD(undeafened);
 		AST_STRING_FIELD(onlyone);
 		AST_STRING_FIELD(thereare);
 		AST_STRING_FIELD(otherinparty);
diff --git a/bridges/bridge_multiplexed.c b/bridges/bridge_multiplexed.c
index cd30266..190f790 100644
--- a/bridges/bridge_multiplexed.c
+++ b/bridges/bridge_multiplexed.c
@@ -386,7 +386,7 @@ static enum ast_bridge_write_result multiplexed_bridge_write(struct ast_bridge *
 	}
 
 	if (other->state == AST_BRIDGE_CHANNEL_STATE_WAIT) {
-		ast_write(other->chan, frame);
+		ast_bridge_handle_channel_write(bridge, other, frame);
 	}
 
 	return AST_BRIDGE_WRITE_SUCCESS;
diff --git a/bridges/bridge_simple.c b/bridges/bridge_simple.c
index 69e4114..1623ce0 100644
--- a/bridges/bridge_simple.c
+++ b/bridges/bridge_simple.c
@@ -81,7 +81,7 @@ static enum ast_bridge_write_result simple_bridge_write(struct ast_bridge *bridg
 
 	/* Write the frame out if they are in the waiting state... don't worry about freeing it, the bridging core will take care of it */
 	if (other->state == AST_BRIDGE_CHANNEL_STATE_WAIT) {
-		ast_write(other->chan, frame);
+		ast_bridge_handle_channel_write(bridge, other, frame);
 	}
 
 	return AST_BRIDGE_WRITE_SUCCESS;
diff --git a/bridges/bridge_softmix.c b/bridges/bridge_softmix.c
index 52e5551..5754e41 100644
--- a/bridges/bridge_softmix.c
+++ b/bridges/bridge_softmix.c
@@ -435,7 +435,7 @@ static void softmix_pass_dtmf(struct ast_bridge *bridge, struct ast_bridge_chann
 		if (tmp == bridge_channel) {
 			continue;
 		}
-		ast_write(tmp->chan, frame);
+		ast_bridge_handle_channel_write(bridge, tmp, frame);
 	}
 }
 
@@ -447,7 +447,7 @@ static void softmix_pass_video_top_priority(struct ast_bridge *bridge, struct as
 			continue;
 		}
 		if (ast_bridge_is_video_src(bridge, tmp->chan) == 1) {
-			ast_write(tmp->chan, frame);
+			ast_bridge_handle_channel_write(bridge, tmp, frame);
 			break;
 		}
 	}
@@ -463,7 +463,7 @@ static void softmix_pass_video_all(struct ast_bridge *bridge, struct ast_bridge_
 		if ((tmp->chan == bridge_channel->chan) && !echo) {
 			continue;
 		}
-		ast_write(tmp->chan, frame);
+		ast_bridge_handle_channel_write(bridge, tmp, frame);
 	}
 }
 
@@ -563,7 +563,7 @@ static enum ast_bridge_write_result softmix_bridge_write(struct ast_bridge *brid
 
 	/* If a frame is ready to be written out, do so */
 	if (sc->have_frame) {
-		ast_write(bridge_channel->chan, &sc->write_frame);
+		ast_bridge_handle_channel_write(bridge, bridge_channel, &sc->write_frame);
 		sc->have_frame = 0;
 	}
 
@@ -582,7 +582,7 @@ bridge_write_cleanup:
 	 * the conference to the channel. */
 	ast_mutex_lock(&sc->lock);
 	if (sc->have_frame) {
-		ast_write(bridge_channel->chan, &sc->write_frame);
+		ast_bridge_handle_channel_write(bridge, bridge_channel, &sc->write_frame);
 		sc->have_frame = 0;
 	}
 	ast_mutex_unlock(&sc->lock);
@@ -598,7 +598,7 @@ static int softmix_bridge_poke(struct ast_bridge *bridge, struct ast_bridge_chan
 	ast_mutex_lock(&sc->lock);
 
 	if (sc->have_frame) {
-		ast_write(bridge_channel->chan, &sc->write_frame);
+		ast_bridge_handle_channel_write(bridge, bridge_channel, &sc->write_frame);
 		sc->have_frame = 0;
 	}
 
@@ -850,16 +850,24 @@ static int softmix_bridge_thread(struct ast_bridge *bridge)
 
 			ast_mutex_lock(&sc->lock);
 
-			/* Make SLINEAR write frame from local buffer */
-			if (sc->write_frame.subclass.format.id != cur_slin_id) {
-				ast_format_set(&sc->write_frame.subclass.format, cur_slin_id, 0);
+			if (bridge->features.deaf ||
+			    (bridge_channel->features && bridge_channel->features->deaf)) {
+				/* For deaf channels post a null frame */
+				sc->write_frame.frametype = AST_FRAME_NULL;
+			} else {
+				/* Make SLINEAR write frame from local buffer */
+				sc->write_frame.frametype = AST_FRAME_VOICE;
+				if (sc->write_frame.subclass.format.id != cur_slin_id) {
+					ast_format_set(&sc->write_frame.subclass.format, cur_slin_id, 0);
+				}
+				sc->write_frame.datalen = softmix_datalen;
+				sc->write_frame.samples = softmix_samples;
+				memcpy(sc->final_buf, buf, softmix_datalen);
+
+				/* process the softmix channel's new write audio */
+				softmix_process_write_audio(&trans_helper,
+					ast_channel_rawwriteformat(bridge_channel->chan), sc);
 			}
-			sc->write_frame.datalen = softmix_datalen;
-			sc->write_frame.samples = softmix_samples;
-			memcpy(sc->final_buf, buf, softmix_datalen);
-
-			/* process the softmix channel's new write audio */
-			softmix_process_write_audio(&trans_helper, ast_channel_rawwriteformat(bridge_channel->chan), sc);
 
 			/* The frame is now ready for use... */
 			sc->have_frame = 1;
diff --git a/configs/confbridge.conf.sample b/configs/confbridge.conf.sample
index 7484b28..3b0ce85 100644
--- a/configs/confbridge.conf.sample
+++ b/configs/confbridge.conf.sample
@@ -16,6 +16,7 @@ type=user
 ;admin=yes     ; Sets if the user is an admin or not. Off by default.
 ;marked=yes    ; Sets if this is a marked user or not. Off by default.
 ;startmuted=yes; Sets if all users should start out muted. Off by default
+;startdeaf=yes ; Sets if all users should start out deaf. Off by default.
 ;music_on_hold_when_empty=yes  ; Sets whether MOH should be played when only
                                ; one person is in the conference or when the
                                ; the user is waiting on a marked user to enter
@@ -210,6 +211,8 @@ type=bridge
 ;sound_kicked ; The sound played to a user who has been kicked from the conference.
 ;sound_muted  ; The sound played when the mute option it toggled on.
 ;sound_unmuted  ; The sound played when the mute option it toggled off.
+;sound_deafened  ; The sound played when the deaf option is toggled on.
+;sound_undeafened  ; The sound played when the deaf option is toggled off.
 ;sound_only_person ; The sound played when the user is the only person in the conference.
 ;sound_only_one ; The sound played to a user when there is only one other
                 ; person is in the conference.
@@ -264,6 +267,8 @@ type=bridge
 ; toggle_mute      ; Toggle turning on and off mute.  Mute will make the user silent
                    ; to everyone else, but the user will still be able to listen in.
                    ; continue to collect the dtmf sequence.
+; toggle_deaf      ; Toggle turning on and off deaf.  Deaf will make the user to hear
+                   ; only silence, but the user will still be able to talk.
 ; no_op ; This action does nothing (No Operation). Its only real purpose exists for
         ; being able to reserve a sequence in the config as a menu exit sequence.
 ; decrease_listening_volume ; Decreases the channel's listening volume.
diff --git a/include/asterisk/bridging_features.h b/include/asterisk/bridging_features.h
index e377ca6..5ce3d56 100644
--- a/include/asterisk/bridging_features.h
+++ b/include/asterisk/bridging_features.h
@@ -127,6 +127,8 @@ struct ast_bridge_features {
 	unsigned int usable:1;
 	/*! Bit to indicate whether the channel/bridge is muted or not */
 	unsigned int mute:1;
+	/*! Bit to indicate whether the channel/bridge is deaf or not */
+	unsigned int deaf:1;
 	/*! Bit to indicate whether DTMF should be passed into the bridge tech or not.  */
 	unsigned int dtmf_passthrough:1;
 
diff --git a/include/asterisk/bridging_technology.h b/include/asterisk/bridging_technology.h
index 3d2e870..1ecb4c1 100644
--- a/include/asterisk/bridging_technology.h
+++ b/include/asterisk/bridging_technology.h
@@ -143,6 +143,21 @@ int ast_bridge_technology_unregister(struct ast_bridge_technology *technology);
  */
 void ast_bridge_handle_trip(struct ast_bridge *bridge, struct ast_bridge_channel *bridge_channel, struct ast_channel *chan, int outfd);
 
+/*! \brief Used by bridging technologies to hand off a frame to be written to a bridge_channel.
+ *
+ * \param bridge The bridge that the channel is part of.
+ * \param bridge_channel The bridge channel to which the frame is written to.
+ * \param frame The frame to write.
+ *
+ * \retval 0 on success
+ * \retval -1 on failure
+ *
+ * \note This function is essentially a wrapper for ast_write(). The bridging core has some features associated with it
+ * that requires it to have control over how frames are written into a channel.  For these features to be available, the bridging
+ * technology must use this wrapper function over ast_write when pushing a frame out a channel.
+ */
+int ast_bridge_handle_channel_write(struct ast_bridge *bridge, struct ast_bridge_channel *bridge_channel, struct ast_frame *frame);
+
 /*! \brief Lets the bridging indicate when a bridge channel has stopped or started talking.
  *
  * \note All DSP functionality on the bridge has been pushed down to the lowest possible
diff --git a/main/bridging.c b/main/bridging.c
index 465d033..4f67e90 100644
--- a/main/bridging.c
+++ b/main/bridging.c
@@ -337,6 +337,28 @@ void ast_bridge_handle_trip(struct ast_bridge *bridge, struct ast_bridge_channel
 	return;
 }
 
+int ast_bridge_handle_channel_write(struct ast_bridge *bridge, struct ast_bridge_channel *bridge_channel, struct ast_frame *frame)
+{
+	if (frame->frametype == AST_FRAME_VOICE &&
+	    (bridge->features.deaf ||
+	     (bridge_channel->features && bridge_channel->features->deaf))) {
+		short buf[frame->samples];
+		struct ast_frame sframe = {
+			.frametype = AST_FRAME_VOICE,
+			.data.ptr = buf,
+			.samples = frame->samples,
+			.datalen = sizeof(buf),
+		};
+		ast_format_set(&sframe.subclass.format, AST_FORMAT_SLINEAR, 0);
+		memset(buf, 0, sizeof(buf));
+
+		return ast_write(bridge_channel->chan, &sframe);
+	}
+
+	return ast_write(bridge_channel->chan, frame);
+}
+
+
 /*! \brief Generic thread loop, TODO: Rethink this/improve it */
 static int generic_thread_loop(struct ast_bridge *bridge)
 {
-- 
1.7.12