Bridging: Allow channels to define bridging hooks

This patch allows the current owner of a channel to define various
feature hooks to be made available once the channel has entered a
bridge. This includes any hooks that are setup on the
ast_bridge_features struct such as DTMF hooks, bridge event hooks
(join, leave, etc.), and interval hooks.

Review: https://reviewboard.asterisk.org/r/3649/


git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@417361 65c4cc65-6c06-0410-ace0-fbb531ad65f3

3 files changed, 134 insertions, 1 deletions

diff --git a/main/bridge.c b/main/bridge.c
index 35287e278..41053eb8a 100644
--- a/main/bridge.c
+++ b/main/bridge.c
@@ -3327,6 +3327,64 @@ static int bridge_dtmf_hook_sort(const void *obj_left, const void *obj_right, in
 	return cmp;
 }
 
+/*! \brief Callback for merging hook ao2_containers */
+static int merge_container_cb(void *obj, void *data, int flags)
+{
+	ao2_link(data, obj);
+	return 0;
+}
+
+/*! \brief Wrapper for interval hooks that calls into the wrapped hook */
+static int interval_wrapper_cb(struct ast_bridge_channel *bridge_channel, void *obj)
+{
+	struct ast_bridge_hook_timer *hook = obj;
+
+	return hook->generic.callback(bridge_channel, hook->generic.hook_pvt);
+}
+
+/*! \brief Destructor for the hook wrapper */
+static void interval_wrapper_pvt_dtor(void *obj)
+{
+	ao2_cleanup(obj);
+}
+
+/*! \brief Wrap the provided interval hook and add it to features */
+static void wrap_hook(struct ast_bridge_features *features, struct ast_bridge_hook_timer *hook)
+{
+	/* Break out of the current wrapper if it exists to avoid multiple layers */
+	if (hook->generic.callback == interval_wrapper_cb) {
+		hook = hook->generic.hook_pvt;
+	}
+
+	ast_bridge_interval_hook(features, hook->timer.flags, hook->timer.interval,
+		interval_wrapper_cb, ao2_bump(hook), interval_wrapper_pvt_dtor,
+		hook->generic.remove_flags.flags);
+}
+
+void ast_bridge_features_merge(struct ast_bridge_features *into, const struct ast_bridge_features *from)
+{
+	struct ast_bridge_hook_timer *hook;
+	int idx;
+
+	/* Merge hook containers */
+	ao2_callback(from->dtmf_hooks, 0, merge_container_cb, into->dtmf_hooks);
+	ao2_callback(from->other_hooks, 0, merge_container_cb, into->other_hooks);
+
+	/* Merge hook heaps */
+	ast_heap_wrlock(from->interval_hooks);
+	for (idx = 1; (hook = ast_heap_peek(from->interval_hooks, idx)); idx++) {
+		wrap_hook(into, hook);
+	}
+	ast_heap_unlock(from->interval_hooks);
+
+	/* Merge feature flags */
+	into->feature_flags.flags |= from->feature_flags.flags;
+	into->usable |= from->usable;
+
+	into->mute |= from->mute;
+	into->dtmf_passthrough |= from->dtmf_passthrough;
+}
+
 /* XXX ASTERISK-21271 make ast_bridge_features_init() static when make ast_bridge_join() requires features to be allocated. */
 int ast_bridge_features_init(struct ast_bridge_features *features)
 {
diff --git a/main/bridge_channel.c b/main/bridge_channel.c
index 9b1b5737e..7d1c65367 100644
--- a/main/bridge_channel.c
+++ b/main/bridge_channel.c
@@ -2187,6 +2187,7 @@ static void bridge_channel_event_join_leave(struct ast_bridge_channel *bridge_ch
 int bridge_channel_internal_join(struct ast_bridge_channel *bridge_channel)
 {
 	int res = 0;
+	struct ast_bridge_features *channel_features;
 
 	ast_format_copy(&bridge_channel->read_format, ast_channel_readformat(bridge_channel->chan));
 	ast_format_copy(&bridge_channel->write_format, ast_channel_writeformat(bridge_channel->chan));
@@ -2201,8 +2202,8 @@ int bridge_channel_internal_join(struct ast_bridge_channel *bridge_channel)
 	 */
 	ast_bridge_lock(bridge_channel->bridge);
 
-	/* Make sure we're still good to be put into a bridge */
 	ast_channel_lock(bridge_channel->chan);
+	/* Make sure we're still good to be put into a bridge */
 	if (ast_channel_internal_bridge(bridge_channel->chan)
 		|| ast_test_flag(ast_channel_flags(bridge_channel->chan), AST_FLAG_ZOMBIE)) {
 		ast_channel_unlock(bridge_channel->chan);
@@ -2214,6 +2215,12 @@ int bridge_channel_internal_join(struct ast_bridge_channel *bridge_channel)
 		return -1;
 	}
 	ast_channel_internal_bridge_set(bridge_channel->chan, bridge_channel->bridge);
+
+	/* Attach features requested by the channel */
+	channel_features = ast_channel_feature_hooks_get(bridge_channel->chan);
+	if (channel_features) {
+		ast_bridge_features_merge(bridge_channel->features, channel_features);
+	}
 	ast_channel_unlock(bridge_channel->chan);
 
 	/* Add the jitterbuffer if the channel requires it */
diff --git a/main/channel.c b/main/channel.c
index 04c396a71..7d9f04837 100644
--- a/main/channel.c
+++ b/main/channel.c
@@ -10453,3 +10453,71 @@ void ast_channel_end_dtmf(struct ast_channel *chan, char digit, struct timeval s
 	ast_log(LOG_DTMF, "DTMF end '%c' simulated on %s due to %s, duration %ld ms\n",
 		digit, ast_channel_name(chan), why, duration);
 }
+
+static void features_destroy(void *obj)
+{
+	ast_bridge_features_destroy(obj);
+}
+
+static const struct ast_datastore_info bridge_features_info = {
+	.type = "bridge-features",
+	.destroy = features_destroy,
+};
+
+struct ast_bridge_features *ast_channel_feature_hooks_get(struct ast_channel *chan)
+{
+	struct ast_datastore *datastore;
+
+	datastore = ast_channel_datastore_find(chan, &bridge_features_info, NULL);
+	if (!datastore) {
+		return NULL;
+	}
+	return datastore->data;
+}
+
+static int channel_feature_hooks_set_full(struct ast_channel *chan, struct ast_bridge_features *features, int replace)
+{
+	struct ast_datastore *datastore;
+	struct ast_bridge_features *ds_features;
+
+	datastore = ast_channel_datastore_find(chan, &bridge_features_info, NULL);
+	if (datastore) {
+		ds_features = datastore->data;
+		if (replace) {
+			ast_bridge_features_cleanup(ds_features);
+			ast_bridge_features_init(ds_features);
+		}
+		if (features) {
+			ast_bridge_features_merge(ds_features, features);
+		}
+		return 0;
+	}
+
+	datastore = ast_datastore_alloc(&bridge_features_info, NULL);
+	if (!datastore) {
+		return -1;
+	}
+
+	ds_features = ast_bridge_features_new();
+	if (!ds_features) {
+		ast_datastore_free(datastore);
+		return -1;
+	}
+
+	if (features) {
+		ast_bridge_features_merge(ds_features, features);
+	}
+	datastore->data = ds_features;
+	ast_channel_datastore_add(chan, datastore);
+	return 0;
+}
+
+int ast_channel_feature_hooks_append(struct ast_channel *chan, struct ast_bridge_features *features)
+{
+	return channel_feature_hooks_set_full(chan, features, 0);
+}
+
+int ast_channel_feature_hooks_replace(struct ast_channel *chan, struct ast_bridge_features *features)
+{
+	return channel_feature_hooks_set_full(chan, features, 1);
+}