core: Add stream topology changing primitives with tests.

This change adds a few things to facilitate stream topology changing:

1. Control frame types have been added for use by the channel driver
to notify the application that the channel wants to change the stream
topology or that a stream topology change has been accepted. They are
also used by the indicate interface to the channel that the application
uses to indicate it wants to do the same.

2. Legacy behavior has been adopted in ast_read() such that if a
channel requests a stream topology change it is denied automatically
and the current stream topology is preserved if the application is
not capable of handling streams.

Tests have also been written which confirm the multistream and
non-multistream behavior.

ASTERISK-26839

Change-Id: Ia68ef22bca8e8457265ca4f0f9de600cbcc10bc9

1 files changed, 239 insertions, 0 deletions

diff --git a/tests/test_stream.c b/tests/test_stream.c
index 7c7897697..3bab67c2c 100644
--- a/tests/test_stream.c
+++ b/tests/test_stream.c
@@ -813,6 +813,8 @@ struct mock_channel_pvt {
 	int frame_count;
 	int streams;
 	int frames_per_read;
+	unsigned int indicated_change_request;
+	unsigned int indicated_changed;
 };
 
 static struct ast_frame *mock_channel_read(struct ast_channel *chan)
@@ -860,6 +862,19 @@ static int mock_channel_write(struct ast_channel *chan, struct ast_frame *fr)
 	return 0;
 }
 
+static int mock_channel_indicate(struct ast_channel *chan, int condition, const void *data, size_t datalen)
+{
+	struct mock_channel_pvt *pvt = ast_channel_tech_pvt(chan);
+
+	if (condition == AST_CONTROL_STREAM_TOPOLOGY_REQUEST_CHANGE) {
+		pvt->indicated_change_request = 1;
+	} else if (condition == AST_CONTROL_STREAM_TOPOLOGY_CHANGED) {
+		pvt->indicated_changed = 1;
+	}
+
+	return 0;
+}
+
 static int mock_channel_write_stream(struct ast_channel *chan, int stream_num, struct ast_frame *fr)
 {
 	struct mock_channel_pvt *pvt = ast_channel_tech_pvt(chan);
@@ -1542,6 +1557,222 @@ AST_TEST_DEFINE(stream_read_multistream)
 	return res;
 }
 
+AST_TEST_DEFINE(stream_topology_change_request_from_application_non_multistream)
+{
+	struct ast_channel_tech tech = {
+		.read = mock_channel_read,
+		.indicate = mock_channel_indicate,
+		.hangup = mock_channel_hangup,
+	};
+	struct ast_channel *mock_channel;
+	struct mock_channel_pvt *pvt;
+	enum ast_test_result_state res = AST_TEST_PASS;
+	int change_res;
+	RAII_VAR(struct ast_stream_topology *, topology, NULL, ast_stream_topology_free);
+
+	switch (cmd) {
+	case TEST_INIT:
+		info->name = "stream_topology_change_request_from_application_non_multistream";
+		info->category = "/main/stream/";
+		info->summary = "stream topology changing on non-multistream channel test";
+		info->description =
+			"Test that an application trying to change the stream topology of a non-multistream channel gets a failure";
+		return AST_TEST_NOT_RUN;
+	case TEST_EXECUTE:
+		break;
+	}
+
+	mock_channel = make_channel(test, 1, &tech);
+	ast_test_validate_cleanup(test, mock_channel, res, done);
+
+	pvt = ast_channel_tech_pvt(mock_channel);
+	pvt->indicated_change_request = 0;
+	pvt->indicated_changed = 0;
+
+	topology = ast_stream_topology_alloc();
+	ast_test_validate_cleanup(test, topology, res, done);
+
+	change_res = ast_channel_request_stream_topology_change(mock_channel, topology);
+
+	ast_test_validate_cleanup(test, change_res == -1, res, done);
+	ast_test_validate_cleanup(test, !pvt->indicated_change_request, res, done);
+
+	change_res = ast_channel_stream_topology_changed(mock_channel, topology);
+
+	ast_test_validate_cleanup(test, change_res == -1, res, done);
+	ast_test_validate_cleanup(test, !pvt->indicated_changed, res, done);
+
+done:
+	ast_hangup(mock_channel);
+
+	return res;
+}
+
+AST_TEST_DEFINE(stream_topology_change_request_from_channel_non_multistream)
+{
+	struct ast_channel_tech tech = {
+		.read_stream = mock_channel_read,
+		.write_stream = mock_channel_write_stream,
+		.indicate = mock_channel_indicate,
+		.hangup = mock_channel_hangup,
+	};
+	struct ast_channel *mock_channel;
+	struct mock_channel_pvt *pvt;
+	enum ast_test_result_state res = AST_TEST_PASS;
+	RAII_VAR(struct ast_stream_topology *, topology, NULL, ast_stream_topology_free);
+	struct ast_frame request_change = {
+		.frametype = AST_FRAME_CONTROL,
+		.subclass.integer = AST_CONTROL_STREAM_TOPOLOGY_REQUEST_CHANGE,
+	};
+	struct ast_frame *fr = NULL;
+
+	switch (cmd) {
+	case TEST_INIT:
+		info->name = "stream_topology_change_request_from_channel_non_multistream";
+		info->category = "/main/stream/";
+		info->summary = "channel requesting stream topology change to non-multistream application test";
+		info->description =
+			"Test that a channel requesting a stream topology change from a non-multistream application does not work";
+		return AST_TEST_NOT_RUN;
+	case TEST_EXECUTE:
+		break;
+	}
+
+	mock_channel = make_channel(test, 1, &tech);
+	ast_test_validate_cleanup(test, mock_channel, res, done);
+
+	pvt = ast_channel_tech_pvt(mock_channel);
+	pvt->indicated_changed = 0;
+
+	topology = ast_stream_topology_alloc();
+	ast_test_validate_cleanup(test, topology, res, done);
+
+	request_change.data.ptr = topology;
+	ast_queue_frame(mock_channel, &request_change);
+
+	fr = ast_read(mock_channel);
+	ast_test_validate_cleanup(test, fr, res, done);
+	ast_test_validate_cleanup(test, fr == &ast_null_frame, res, done);
+	ast_test_validate_cleanup(test, pvt->indicated_changed, res, done);
+
+done:
+	if (fr) {
+		ast_frfree(fr);
+	}
+	ast_hangup(mock_channel);
+
+	return res;
+}
+
+AST_TEST_DEFINE(stream_topology_change_request_from_application)
+{
+	struct ast_channel_tech tech = {
+		.read_stream = mock_channel_read,
+		.write_stream = mock_channel_write_stream,
+		.indicate = mock_channel_indicate,
+		.hangup = mock_channel_hangup,
+	};
+	struct ast_channel *mock_channel;
+	struct mock_channel_pvt *pvt;
+	enum ast_test_result_state res = AST_TEST_PASS;
+	int change_res;
+	RAII_VAR(struct ast_stream_topology *, topology, NULL, ast_stream_topology_free);
+
+	switch (cmd) {
+	case TEST_INIT:
+		info->name = "stream_topology_change_request_from_application";
+		info->category = "/main/stream/";
+		info->summary = "stream topology change request from application test";
+		info->description =
+			"Test that an application changing the stream topology of a multistream capable channel receives success";
+		return AST_TEST_NOT_RUN;
+	case TEST_EXECUTE:
+		break;
+	}
+
+	mock_channel = make_channel(test, 1, &tech);
+	ast_test_validate_cleanup(test, mock_channel, res, done);
+
+	pvt = ast_channel_tech_pvt(mock_channel);
+	pvt->indicated_change_request = 0;
+	pvt->indicated_changed = 0;
+
+	topology = ast_stream_topology_alloc();
+	ast_test_validate_cleanup(test, topology, res, done);
+
+	change_res = ast_channel_request_stream_topology_change(mock_channel, topology);
+
+	ast_test_validate_cleanup(test, !change_res, res, done);
+	ast_test_validate_cleanup(test, pvt->indicated_change_request, res, done);
+
+	change_res = ast_channel_stream_topology_changed(mock_channel, topology);
+
+	ast_test_validate_cleanup(test, !change_res, res, done);
+	ast_test_validate_cleanup(test, pvt->indicated_changed, res, done);
+
+done:
+	ast_hangup(mock_channel);
+
+	return res;
+}
+
+AST_TEST_DEFINE(stream_topology_change_request_from_channel)
+{
+	struct ast_channel_tech tech = {
+		.read_stream = mock_channel_read,
+		.write_stream = mock_channel_write_stream,
+		.indicate = mock_channel_indicate,
+		.hangup = mock_channel_hangup,
+	};
+	struct ast_channel *mock_channel;
+	struct mock_channel_pvt *pvt;
+	enum ast_test_result_state res = AST_TEST_PASS;
+	RAII_VAR(struct ast_stream_topology *, topology, NULL, ast_stream_topology_free);
+	struct ast_frame request_change = {
+		.frametype = AST_FRAME_CONTROL,
+		.subclass.integer = AST_CONTROL_STREAM_TOPOLOGY_REQUEST_CHANGE,
+	};
+	struct ast_frame *fr = NULL;
+
+	switch (cmd) {
+	case TEST_INIT:
+		info->name = "stream_topology_change_request_from_channel";
+		info->category = "/main/stream/";
+		info->summary = "channel requesting stream topology change to multistream application test";
+		info->description =
+			"Test that a channel requesting a stream topology change from a multistream application works";
+		return AST_TEST_NOT_RUN;
+	case TEST_EXECUTE:
+		break;
+	}
+
+	mock_channel = make_channel(test, 1, &tech);
+	ast_test_validate_cleanup(test, mock_channel, res, done);
+
+	pvt = ast_channel_tech_pvt(mock_channel);
+	pvt->indicated_changed = 0;
+
+	topology = ast_stream_topology_alloc();
+	ast_test_validate_cleanup(test, topology, res, done);
+
+	request_change.data.ptr = topology;
+	ast_queue_frame(mock_channel, &request_change);
+
+	fr = ast_read_stream(mock_channel);
+	ast_test_validate_cleanup(test, fr, res, done);
+	ast_test_validate_cleanup(test, fr->frametype == AST_FRAME_CONTROL, res, done);
+	ast_test_validate_cleanup(test, fr->subclass.integer == AST_CONTROL_STREAM_TOPOLOGY_REQUEST_CHANGE, res, done);
+	ast_test_validate_cleanup(test, !pvt->indicated_changed, res, done);
+
+done:
+	if (fr) {
+		ast_frfree(fr);
+	}
+	ast_hangup(mock_channel);
+
+	return res;
+}
+
 static int unload_module(void)
 {
 	AST_TEST_UNREGISTER(stream_create);
@@ -1562,6 +1793,10 @@ static int unload_module(void)
 	AST_TEST_UNREGISTER(stream_write_multistream);
 	AST_TEST_UNREGISTER(stream_read_non_multistream);
 	AST_TEST_UNREGISTER(stream_read_multistream);
+	AST_TEST_UNREGISTER(stream_topology_change_request_from_application_non_multistream);
+	AST_TEST_UNREGISTER(stream_topology_change_request_from_channel_non_multistream);
+	AST_TEST_UNREGISTER(stream_topology_change_request_from_application);
+	AST_TEST_UNREGISTER(stream_topology_change_request_from_channel);
 	return 0;
 }
 
@@ -1584,6 +1819,10 @@ static int load_module(void)
 	AST_TEST_REGISTER(stream_write_multistream);
 	AST_TEST_REGISTER(stream_read_non_multistream);
 	AST_TEST_REGISTER(stream_read_multistream);
+	AST_TEST_REGISTER(stream_topology_change_request_from_application_non_multistream);
+	AST_TEST_REGISTER(stream_topology_change_request_from_channel_non_multistream);
+	AST_TEST_REGISTER(stream_topology_change_request_from_application);
+	AST_TEST_REGISTER(stream_topology_change_request_from_channel);
 	return AST_MODULE_LOAD_SUCCESS;
 }