From 647c53c41fa36ab8e5b3e8824952aea01c76e37e Mon Sep 17 00:00:00 2001
From: George Joseph <gjoseph@digium.com>
Date: Mon, 20 Jul 2020 13:39:14 -0600
Subject: [PATCH] ACN: Changes specific to the core
Allow passing a topology from the called channel back to the
calling channel.
* Added a new function ast_queue_answer() that accepts a stream
topology and queues an ANSWER CONTROL frame with it as the
data. This allows the called channel to indicate its resolved
topology.
* Added a new virtual function to the channel tech structure
answer_with_stream_topology() that allows the calling channel
to receive the called channel's topology. Added
ast_raw_answer_with_stream_topology() that invokes that virtual
function.
* Modified app_dial.c and features.c to grab the topology from the
ANSWER frame queued by the answering channel and send it to
the calling channel with ast_raw_answer_with_stream_topology().
* Modified frame.c to automatically cleanup the reference
to the topology on ANSWER frames.
Added a few debugging messages to stream.c.
Change-Id: I0115d2ed68d6bae0f87e85abcf16c771bdaf992c
---
apps/app_dial.c | 32 ++++++++++++++++--
include/asterisk/channel.h | 67 ++++++++++++++++++++++++++++++++++++++
include/asterisk/frame.h | 8 +++--
main/channel.c | 24 ++++++++++++--
main/features.c | 8 ++++-
main/frame.c | 9 +++++
main/stream.c | 17 ++++++++--
7 files changed, 155 insertions(+), 10 deletions(-)
diff --git a/apps/app_dial.c b/apps/app_dial.c
index 95f36d7ab2..9e1148753c 100644
--- a/apps/app_dial.c
+++ b/apps/app_dial.c
@@ -1204,7 +1204,8 @@ static struct ast_channel *wait_for_answer(struct ast_channel *in,
struct privacy_args *pa,
const struct cause_args *num_in, int *result, char *dtmf_progress,
const int ignore_cc,
- struct ast_party_id *forced_clid, struct ast_party_id *stored_clid)
+ struct ast_party_id *forced_clid, struct ast_party_id *stored_clid,
+ struct ast_bridge_config *config)
{
struct cause_args num = *num_in;
int prestart = num.busy + num.congestion + num.nochan;
@@ -1418,6 +1419,18 @@ static struct ast_channel *wait_for_answer(struct ast_channel *in,
}
}
peer = c;
+ /* Answer can optionally include a topology */
+ if (f->subclass.topology) {
+ /*
+ * We need to bump the refcount on the topology to prevent it
+ * from being cleaned up when the frame is cleaned up.
+ */
+ config->answer_topology = ao2_bump(f->subclass.topology);
+ ast_trace(2, "%s Found topology in frame: %p %p %s\n",
+ ast_channel_name(peer), f, config->answer_topology,
+ ast_str_tmp(256, ast_stream_topology_to_str(config->answer_topology, &STR_TMP)));
+ }
+
/* Inform everyone else that they've been canceled.
* The dial end event for the peer will be sent out after
* other Dial options have been handled.
@@ -2217,7 +2230,7 @@ static int dial_exec_full(struct ast_channel *chan, const char *data, struct ast
struct dial_head out_chans = AST_LIST_HEAD_NOLOCK_INIT_VALUE; /* list of destinations */
struct chanlist *outgoing;
struct chanlist *tmp;
- struct ast_channel *peer;
+ struct ast_channel *peer = NULL;
int to; /* timeout */
struct cause_args num = { chan, 0, 0, 0 };
int cause;
@@ -2838,7 +2851,7 @@ static int dial_exec_full(struct ast_channel *chan, const char *data, struct ast
}
peer = wait_for_answer(chan, &out_chans, &to, peerflags, opt_args, &pa, &num, &result,
- dtmf_progress, ignore_cc, &forced_clid, &stored_clid);
+ dtmf_progress, ignore_cc, &forced_clid, &stored_clid, &config);
if (!peer) {
if (result) {
@@ -3267,6 +3280,7 @@ static int dial_exec_full(struct ast_channel *chan, const char *data, struct ast
ast_channel_setoption(chan, AST_OPTION_OPRMODE, &oprmode, sizeof(oprmode), 0);
}
setup_peer_after_bridge_goto(chan, peer, &opts, opt_args);
+
res = ast_bridge_call(chan, peer, &config);
}
}
@@ -3304,6 +3318,18 @@ out:
}
done:
+ if (config.answer_topology) {
+ ast_trace(2, "%s Cleaning up topology: %p %s\n",
+ peer ? ast_channel_name(peer) : "<no channel>", &config.answer_topology,
+ ast_str_tmp(256, ast_stream_topology_to_str(config.answer_topology, &STR_TMP)));
+
+ /*
+ * At this point, the channel driver that answered should have bumped the
+ * topology refcount for itself. Here we're cleaning up the reference we added
+ * in wait_for_answer().
+ */
+ ast_stream_topology_free(config.answer_topology);
+ }
if (config.warning_sound) {
ast_free((char *)config.warning_sound);
}
diff --git a/include/asterisk/channel.h b/include/asterisk/channel.h
index cc90c8304a..baefeddaed 100644
--- a/include/asterisk/channel.h
+++ b/include/asterisk/channel.h
@@ -707,6 +707,19 @@ struct ast_channel_tech {
/*! \brief Answer the channel */
int (* const answer)(struct ast_channel *chan);
+ /*!
+ * \brief Answer the channel with topology
+ * \since 18.0.0
+ *
+ * \param chan The channel to answer
+ * \param topology The topology to use, probably the peer's.
+ *
+ * \note The topology may be NULL when the peer doesn't support streams
+ * or, in the case where transcoding is in effect, when this channel should use
+ * its existing topology.
+ */
+ int (* const answer_with_stream_topology)(struct ast_channel *chan, struct ast_stream_topology *topology);
+
/*!
* \brief Read a frame (or chain of frames from the same stream), in standard format (see frame.h)
*
@@ -1081,6 +1094,10 @@ struct ast_bridge_config {
* exist when the end_bridge_callback is called, then it needs to be fixed up properly
*/
void (*end_bridge_callback_data_fixup)(struct ast_bridge_config *bconfig, struct ast_channel *originator, struct ast_channel *terminator);
+ /*! If the bridge answers the channel this topology should be passed to the channel
+ * and used if the channel supports the answer_with_stream_topology callback.
+ */
+ struct ast_stream_topology *answer_topology;
};
struct chanmon;
@@ -1378,6 +1395,17 @@ int ast_queue_control(struct ast_channel *chan, enum ast_control_frame_type cont
int ast_queue_control_data(struct ast_channel *chan, enum ast_control_frame_type control,
const void *data, size_t datalen);
+/*!
+ * \brief Queue an ANSWER control frame with topology
+ *
+ * \param chan channel to queue frame onto
+ * \param topology topology to be passed through the core to the peer channel
+ *
+ * \retval 0 success
+ * \retval non-zero failure
+ */
+int ast_queue_answer(struct ast_channel *chan, const struct ast_stream_topology *topology);
+
/*!
* \brief Change channel name
*
@@ -1801,6 +1829,31 @@ int ast_auto_answer(struct ast_channel *chan);
*/
int ast_raw_answer(struct ast_channel *chan);
+/*!
+ * \brief Answer a channel passing in a stream topology
+ * \since 18.0.0
+ *
+ * \param chan channel to answer
+ * \param topology the peer's stream topology
+ *
+ * This function answers a channel and handles all necessary call
+ * setup functions.
+ *
+ * \note The channel passed does not need to be locked, but is locked
+ * by the function when needed.
+ *
+ * \note Unlike ast_answer(), this function will not wait for media
+ * flow to begin. The caller should be careful before sending media
+ * to the channel before incoming media arrives, as the outgoing
+ * media may be lost.
+ *
+ * \note The topology is usually that of the peer channel and may be NULL.
+ *
+ * \retval 0 on success
+ * \retval non-zero on failure
+ */
+int ast_raw_answer_with_stream_topology(struct ast_channel *chan, struct ast_stream_topology *topology);
+
/*!
* \brief Answer a channel, with a selectable delay before returning
*
@@ -5054,4 +5107,18 @@ int ast_channel_stream_topology_changed_externally(struct ast_channel *chan);
*/
void *ast_channel_get_stream_topology_change_source(struct ast_channel *chan);
+/*!
+ * \brief Checks if a channel's technology implements a particular callback function
+ * \since 18.0.0
+ *
+ * \param chan The channel
+ * \param function The function to look for
+ *
+ * \retval 1 if the channel has a technology set and it implements the function
+ * \retval 0 if the channel doesn't have a technology set or it doesn't implement the function
+ */
+#define ast_channel_has_tech_function(chan, function) \
+ (ast_channel_tech(chan) ? ast_channel_tech(chan)->function != NULL : 0)
+
+
#endif /* _ASTERISK_CHANNEL_H */
diff --git a/include/asterisk/frame.h b/include/asterisk/frame.h
index c8359ec525..f5a5f2cec5 100644
--- a/include/asterisk/frame.h
+++ b/include/asterisk/frame.h
@@ -147,8 +147,12 @@ enum {
struct ast_frame_subclass {
/*! A frame specific code */
int integer;
- /*! The asterisk media format */
- struct ast_format *format;
+ union {
+ /*! The asterisk media format */
+ struct ast_format *format;
+ /*! The asterisk stream topology */
+ struct ast_stream_topology *topology;
+ };
/*! For video formats, an indication that a frame ended */
unsigned int frame_ending;
};
diff --git a/main/channel.c b/main/channel.c
index 8dd008dd15..c26089a245 100644
--- a/main/channel.c
+++ b/main/channel.c
@@ -1238,6 +1238,17 @@ int ast_queue_control_data(struct ast_channel *chan, enum ast_control_frame_type
return ast_queue_frame(chan, &f);
}
+/*! \brief Queue an ANSWER control frame with topology */
+int ast_queue_answer(struct ast_channel *chan, const struct ast_stream_topology *topology)
+{
+ struct ast_frame f = {
+ AST_FRAME_CONTROL,
+ .subclass.integer = AST_CONTROL_ANSWER,
+ .subclass.topology = (struct ast_stream_topology *)topology,
+ };
+ return ast_queue_frame(chan, &f);
+}
+
/*! \brief Set defer DTMF flag on channel */
int ast_channel_defer_dtmf(struct ast_channel *chan)
{
@@ -2619,7 +2630,8 @@ static void set_channel_answer_time(struct ast_channel *chan)
}
}
-int ast_raw_answer(struct ast_channel *chan)
+
+int ast_raw_answer_with_stream_topology(struct ast_channel *chan, struct ast_stream_topology *topology)
{
int res = 0;
SCOPE_TRACE(1, "%s\n", ast_channel_name(chan));
@@ -2650,7 +2662,10 @@ int ast_raw_answer(struct ast_channel *chan)
case AST_STATE_RINGING:
case AST_STATE_RING:
ast_channel_lock(chan);
- if (ast_channel_tech(chan)->answer) {
+ if (ast_channel_tech(chan)->answer_with_stream_topology) {
+ res = ast_channel_tech(chan)->answer_with_stream_topology(chan, topology);
+
+ } else if (ast_channel_tech(chan)->answer) {
res = ast_channel_tech(chan)->answer(chan);
}
ast_setstate(chan, AST_STATE_UP);
@@ -2667,6 +2682,11 @@ int ast_raw_answer(struct ast_channel *chan)
return res;
}
+int ast_raw_answer(struct ast_channel *chan)
+{
+ return ast_raw_answer_with_stream_topology(chan, NULL);
+}
+
int __ast_answer(struct ast_channel *chan, unsigned int delay)
{
int res = 0;
diff --git a/main/features.c b/main/features.c
index 51cc3ed98d..9810866466 100644
--- a/main/features.c
+++ b/main/features.c
@@ -76,6 +76,7 @@
#include "asterisk/stasis_channels.h"
#include "asterisk/features_config.h"
#include "asterisk/max_forwards.h"
+#include "asterisk/stream.h"
/*** DOCUMENTATION
<application name="Bridge" language="en_US">
@@ -558,12 +559,17 @@ static int pre_bridge_setup(struct ast_channel *chan, struct ast_channel *peer,
set_config_flags(chan, config);
/* Answer if need be */
+
+ res = 0;
+
if (ast_channel_state(chan) != AST_STATE_UP) {
- if (ast_raw_answer(chan)) {
+ res = ast_raw_answer_with_stream_topology(chan, config->answer_topology);
+ if (res != 0) {
return -1;
}
}
+
#ifdef FOR_DEBUG
/* show the two channels and cdrs involved in the bridge for debug & devel purposes */
ast_channel_log("Pre-bridge CHAN Channel info", chan);
diff --git a/main/frame.c b/main/frame.c
index 4eeb3b60d5..3a5ee91bd4 100644
--- a/main/frame.c
+++ b/main/frame.c
@@ -138,6 +138,8 @@ static void __frame_free(struct ast_frame *fr, int cache)
|| fr->frametype == AST_FRAME_VIDEO
|| fr->frametype == AST_FRAME_IMAGE) {
ao2_cleanup(fr->subclass.format);
+ } else if (fr->frametype == AST_FRAME_CONTROL && fr->subclass.integer == AST_CONTROL_ANSWER) {
+ ao2_cleanup(fr->subclass.topology);
}
AST_LIST_INSERT_HEAD(&frames->list, fr, frame_list);
@@ -160,6 +162,8 @@ static void __frame_free(struct ast_frame *fr, int cache)
|| fr->frametype == AST_FRAME_VIDEO
|| fr->frametype == AST_FRAME_IMAGE) {
ao2_cleanup(fr->subclass.format);
+ } else if (fr->frametype == AST_FRAME_CONTROL && fr->subclass.integer == AST_CONTROL_ANSWER) {
+ ao2_cleanup(fr->subclass.topology);
}
ast_free(fr);
@@ -218,6 +222,8 @@ struct ast_frame *__ast_frisolate(struct ast_frame *fr, const char *file, int li
if ((fr->frametype == AST_FRAME_VOICE) || (fr->frametype == AST_FRAME_VIDEO) ||
(fr->frametype == AST_FRAME_IMAGE)) {
ao2_bump(out->subclass.format);
+ } else if (fr->frametype == AST_FRAME_VOICE && fr->subclass.integer == AST_CONTROL_ANSWER) {
+ ao2_bump(out->subclass.topology);
}
out->datalen = fr->datalen;
out->samples = fr->samples;
@@ -348,7 +354,10 @@ struct ast_frame *__ast_frdup(const struct ast_frame *f, const char *file, int l
if ((f->frametype == AST_FRAME_VOICE) || (f->frametype == AST_FRAME_VIDEO) ||
(f->frametype == AST_FRAME_IMAGE)) {
ao2_bump(out->subclass.format);
+ } else if (f->frametype == AST_FRAME_CONTROL && f->subclass.integer == AST_CONTROL_ANSWER) {
+ ao2_bump(out->subclass.topology);
}
+
out->datalen = f->datalen;
out->samples = f->samples;
out->delivery = f->delivery;
diff --git a/main/stream.c b/main/stream.c
index a21177d10c..01b07cad19 100644
--- a/main/stream.c
+++ b/main/stream.c
@@ -602,6 +602,16 @@ struct ast_stream *ast_stream_create_resolved(struct ast_stream *pending_stream,
ast_format_cap_append(joint_caps, single, 0);
ao2_ref(single, -1);
}
+ } else {
+ if (error_message) {
+ ast_str_append(error_message, 0, "No common formats available for media type '%s' ",
+ ast_codec_media_type2str(pending_stream->type));
+ ast_format_cap_append_names(preferred_caps, error_message);
+ ast_str_append(error_message, 0, "<>");
+ ast_format_cap_append_names(nonpreferred_caps, error_message);
+ ast_str_append(error_message, 0, " with prefs: ");
+ ast_stream_codec_prefs_to_str(prefs, error_message);
+ }
}
joint_stream = ast_stream_clone(pending_stream, NULL);
@@ -613,7 +623,7 @@ struct ast_stream *ast_stream_create_resolved(struct ast_stream *pending_stream,
/* ref to joint_caps will be transferred to the stream */
ast_stream_set_formats(joint_stream, joint_caps);
- if (TRACE_ATLEAST(1)) {
+ if (TRACE_ATLEAST(3)) {
struct ast_str *buf = ast_str_create((AST_FORMAT_CAP_NAMES_LEN * 3) + AST_STREAM_MAX_CODEC_PREFS_LENGTH);
if (buf) {
ast_str_set(&buf, 0, "Resolved '%s' stream ", ast_codec_media_type2str(pending_stream->type));
@@ -1040,7 +1050,10 @@ struct ast_stream_topology *ast_stream_topology_create_resolved(
ast_stream_set_state(joint_stream, AST_STREAM_STATE_REMOVED);
} else {
joint_stream = ast_stream_create_resolved(pending_stream, configured_stream, prefs, error_message);
- if (ast_stream_get_format_count(joint_stream) == 0) {
+ if (!joint_stream) {
+ ao2_cleanup(joint_topology);
+ return NULL;
+ } else if (ast_stream_get_format_count(joint_stream) == 0) {
ast_stream_set_state(joint_stream, AST_STREAM_STATE_REMOVED);
}
}
--
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