123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264265266267268269270271272273274275276277278279280281282283284285286287288289290291292293294295296297298299300301302303304305306307308309310311312313314315316317318319320321322323324325326327328329330331332333334335336337338339340341342343344345 |
- /*
- * Asterisk -- An open source telephony toolkit.
- *
- * Copyright (C) 2017, Digium, Inc.
- *
- * Kevin Harwell <kharwell@digium.com>
- *
- * See http://www.asterisk.org for more information about
- * the Asterisk project. Please do not directly contact
- * any of the maintainers of this project for assistance;
- * the project provides a web site, mailing lists and IRC
- * channels for your use.
- *
- * This program is free software, distributed under the terms of
- * the GNU General Public License Version 2. See the LICENSE file
- * at the top of the source tree.
- */
- /*! \file
- *
- * \brief Stream echo application
- *
- * \author Kevin Harwell <kharwell@digium.com>
- */
- /*** MODULEINFO
- <support_level>core</support_level>
- ***/
- #include "asterisk.h"
- #include "asterisk/app.h"
- #include "asterisk/conversions.h"
- #include "asterisk/file.h"
- #include "asterisk/module.h"
- #include "asterisk/channel.h"
- #include "asterisk/stream.h"
- /*** DOCUMENTATION
- <application name="StreamEcho" language="en_US">
- <synopsis>
- Echo media, up to 'N' streams of a type, and DTMF back to the calling party
- </synopsis>
- <syntax>
- <parameter name="num" required="false">
- <para>The number of streams of a type to echo back. If '0' is specified then
- all streams of a type are removed.</para>
- </parameter>
- <parameter name="type" required="false">
- <para>The media type of the stream(s) to add or remove (in the case of "num"
- being '0'). This can be set to either "audio" or "video" (default). If "num"
- is empty (i.e. not specified) then this parameter is ignored.</para>
- </parameter>
- </syntax>
- <description>
- <para>If a "num" (the number of streams) is not given then this simply echos
- back any media or DTMF frames (note, however if '#' is detected then the
- application exits) read from the calling channel back to itself. This means
- for any relevant frame read from a particular stream it is written back out
- to the associated write stream in a one to one fashion.
- </para>
- <para>However if a "num" is specified, and if the calling channel allows it
- (a new offer is made requesting the allowance of additional streams) then any
- any media received, like before, is echoed back onto each stream. However, in
- this case a relevant frame received on a stream of the given "type" is also
- echoed back out to the other streams of that same type. It should be noted that
- when operating in this mode only the first stream found of the given "type" is
- allowed from the original offer. And this first stream found is also the only
- stream of that "type" granted read (send/receive) capabilities in the new offer
- whereas the additional ones are set to receive only.</para>
- <note><para>This does not echo CONTROL, MODEM, or NULL frames.</para></note>
- </description>
- </application>
- ***/
- static const char app[] = "StreamEcho";
- static int stream_echo_write_error(struct ast_channel *chan, struct ast_frame *frame, int pos)
- {
- char frame_type[32];
- const char *media_type;
- struct ast_stream *stream;
- ast_frame_type2str(frame->frametype, frame_type, sizeof(frame_type));
- stream = pos < 0 ?
- ast_channel_get_default_stream(chan, ast_format_get_type(frame->subclass.format)) :
- ast_stream_topology_get_stream(ast_channel_get_stream_topology(chan), pos);
- media_type = ast_codec_media_type2str(ast_stream_get_type(stream));
- ast_log(LOG_ERROR, "%s - unable to write frame type '%s' to stream type '%s' at "
- "position '%d'\n", ast_channel_name(chan), frame_type, media_type,
- ast_stream_get_position(stream));
- return -1;
- }
- static int stream_echo_write(struct ast_channel *chan, struct ast_frame *frame,
- enum ast_media_type type, int one_to_one)
- {
- int i;
- int num;
- struct ast_stream_topology *topology;
- /*
- * Since this is an echo application if we get a frame in on a stream
- * we simply want to echo it back out onto the same stream number.
- */
- num = ast_channel_is_multistream(chan) ? frame->stream_num : -1;
- if (ast_write_stream(chan, num, frame)) {
- return stream_echo_write_error(chan, frame, num);
- }
- /*
- * If the frame's type and given type don't match, or we are operating in
- * a one to one stream echo mode then there is nothing left to do.
- *
- * Note, if the channel is not multi-stream capable then one_to_one will
- * always be true, so it is safe to also not check for that here too.
- */
- if (one_to_one || !frame->subclass.format ||
- ast_format_get_type(frame->subclass.format) != type) {
- return 0;
- }
- /*
- * However, if we are operating in a single stream echoed to many stream
- * mode, and the frame's type matches the given type then we also need to
- * find the other streams of the same type and write out to those streams
- * as well.
- *
- * If we are here, then it's accepted that whatever stream number the frame
- * was read from for the given type is the only one set to send/receive,
- * while the others of the same type are set to receive only. Since we
- * shouldn't assume any order to the streams, we'll loop back through all
- * streams in the channel's topology writing only to those of the same type.
- * And, of course also not the stream which has already been written to.
- */
- topology = ast_channel_get_stream_topology(chan);
- for (i = 0; i < ast_stream_topology_get_count(topology); ++i) {
- struct ast_stream *stream = ast_stream_topology_get_stream(topology, i);
- if (num != i && ast_stream_get_type(stream) == type) {
- if (ast_write_stream(chan, i, frame)) {
- return stream_echo_write_error(chan, frame, i);
- }
- }
- }
- return 0;
- }
- static int stream_echo_perform(struct ast_channel *chan,
- struct ast_stream_topology *topology, enum ast_media_type type)
- {
- int update_sent = 0;
- int request_change = topology != NULL;
- int one_to_one = 1;
- while (ast_waitfor(chan, -1) > -1) {
- struct ast_frame *f;
- if (request_change) {
- /* Request a change to the new topology */
- if (ast_channel_request_stream_topology_change(chan, topology, NULL)) {
- ast_log(LOG_WARNING, "Request stream topology change not supported "
- "by channel '%s'\n", ast_channel_name(chan));
- }
- request_change = 0;
- }
- f = ast_read_stream(chan);
- if (!f) {
- return -1;
- }
- if ((f->frametype == AST_FRAME_DTMF) && (f->subclass.integer == '#')) {
- ast_frfree(f);
- break;
- }
- f->delivery.tv_sec = 0;
- f->delivery.tv_usec = 0;
- if (f->frametype == AST_FRAME_CONTROL) {
- if (f->subclass.integer == AST_CONTROL_VIDUPDATE && !update_sent) {
- if (stream_echo_write(chan, f, type, one_to_one)) {
- ast_frfree(f);
- return -1;
- }
- update_sent = 1;
- } else if (f->subclass.integer == AST_CONTROL_SRCCHANGE) {
- update_sent = 0;
- } else if (f->subclass.integer == AST_CONTROL_STREAM_TOPOLOGY_CHANGED) {
- update_sent = 0;
- one_to_one = 0; /* Switch writing to one to many */
- }
- } else if (f->frametype == AST_FRAME_VIDEO && !update_sent){
- struct ast_frame frame = {
- .frametype = AST_FRAME_CONTROL,
- .subclass.integer = AST_CONTROL_VIDUPDATE,
- };
- stream_echo_write(chan, &frame, type, one_to_one);
- update_sent = 1;
- }
- if (f->frametype != AST_FRAME_CONTROL &&
- f->frametype != AST_FRAME_MODEM &&
- f->frametype != AST_FRAME_NULL &&
- stream_echo_write(chan, f, type, one_to_one)) {
- ast_frfree(f);
- return -1;
- }
- ast_frfree(f);
- }
- return 0;
- }
- static struct ast_stream_topology *stream_echo_topology_alloc(
- struct ast_stream_topology *original, unsigned int num, enum ast_media_type type)
- {
- int i, n = num;
- struct ast_stream_topology *res = ast_stream_topology_alloc();
- if (!res) {
- return NULL;
- }
- /*
- * Clone every stream of a type not matching the given one. If the type
- * matches clone only the first stream found for the given type. Then for
- * that stream clone it again up to num - 1 times. Ignore any other streams
- * of the same matched type in the original topology.
- *
- * So for instance if the original stream contains 1 audio stream and 2 video
- * streams (video stream 'A' and video stream 'B'), num is '3', and the given
- * type is 'video' then the resulting topology will contain a clone of the
- * audio stream along with 3 clones of video stream 'A'. Video stream 'B' is
- * not copied over.
- */
- for (i = 0; i < ast_stream_topology_get_count(original); ++i) {
- struct ast_stream *stream = ast_stream_topology_get_stream(original, i);
- if (!n && ast_stream_get_type(stream) == type) {
- /* Don't copy any[more] of the given type */
- continue;
- }
- if (ast_stream_get_state(stream) == AST_STREAM_STATE_REMOVED) {
- /* Don't copy removed/declined streams */
- continue;
- }
- do {
- stream = ast_stream_clone(stream, NULL);
- if (!stream || ast_stream_topology_append_stream(res, stream) < 0) {
- ast_stream_free(stream);
- ast_stream_topology_free(res);
- return NULL;
- }
- if (ast_stream_get_type(stream) != type) {
- /* Do not multiply non matching streams */
- break;
- }
- /*
- * Since num is not zero yet (i.e. this is first stream found to
- * match on the type) and the types match then loop num - 1 times
- * cloning the same stream.
- */
- ast_stream_set_state(stream, n == num ?
- AST_STREAM_STATE_SENDRECV : AST_STREAM_STATE_SENDONLY);
- } while (--n);
- }
- return res;
- }
- static int stream_echo_exec(struct ast_channel *chan, const char *data)
- {
- int res;
- unsigned int num = 0;
- enum ast_media_type type;
- char *parse;
- struct ast_stream_topology *topology;
- AST_DECLARE_APP_ARGS(args,
- AST_APP_ARG(num);
- AST_APP_ARG(type);
- );
- parse = ast_strdupa(data);
- AST_STANDARD_APP_ARGS(args, parse);
- if (ast_strlen_zero(args.num)) {
- /*
- * If a number is not given then no topology is to be created
- * and renegotiated. The app will just echo back each stream
- * received to itself.
- */
- return stream_echo_perform(chan, NULL, AST_MEDIA_TYPE_UNKNOWN);
- }
- if (ast_str_to_uint(args.num, &num)) {
- ast_log(LOG_ERROR, "Failed to parse the first parameter '%s' into a"
- " greater than or equal to zero\n", args.num);
- return -1;
- }
- type = ast_strlen_zero(args.type) ? AST_MEDIA_TYPE_VIDEO :
- ast_media_type_from_str(args.type);
- topology = stream_echo_topology_alloc(
- ast_channel_get_stream_topology(chan), num, type);
- if (!topology) {
- ast_log(LOG_ERROR, "Unable to create '%u' streams of type '%s' to"
- " the topology\n", num, ast_codec_media_type2str(type));
- return -1;
- }
- res = stream_echo_perform(chan, topology, type);
- if (ast_channel_get_stream_topology(chan) != topology) {
- ast_stream_topology_free(topology);
- }
- return res;
- }
- static int unload_module(void)
- {
- return ast_unregister_application(app);
- }
- static int load_module(void)
- {
- return ast_register_application_xml(app, stream_echo_exec);
- }
- AST_MODULE_INFO_STANDARD(ASTERISK_GPL_KEY, "Stream Echo Application");
|