Separation between hat and callback binding parts

As well as handling reading signals BCM socket using systemd event loop.

Change-Id: I1e121635ec5db489b2bcb88a3101e716bf8883d5
Signed-off-by: Romain Forlot <romain.forlot@iot.bzh>

1 files changed, 252 insertions, 0 deletions

diff --git a/CAN-binder/low-can-binding/binding/low-can-cb.cpp b/CAN-binder/low-can-binding/binding/low-can-cb.cpp
new file mode 100644
index 00000000..414fa910
--- /dev/null
+++ b/CAN-binder/low-can-binding/binding/low-can-cb.cpp
@@ -0,0 +1,252 @@
+/*
+ * Copyright (C) 2015, 2016 "IoT.bzh"
+ * Author "Romain Forlot" <romain.forlot@iot.bzh>
+ * Author "Loic Collignon" <loic.collignon@iot.bzh>
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *	 http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "low-can-hat.hpp"
+
+#include <map>
+#include <queue>
+#include <mutex>
+#include <vector>
+#include <thread>
+#include <json-c/json.h>
+#include <systemd/sd-event.h>
+
+#include "openxc.pb.h"
+#include "configuration.hpp"
+#include "../can/can-bus.hpp"
+#include "../can/can-signals.hpp"
+#include "../can/can-message.hpp"
+#include "../utils/timer.hpp"
+#include "../utils/signals.hpp"
+#include "../diagnostic/diagnostic-message.hpp"
+#include "../utils/openxc-utils.hpp"
+
+extern "C"
+{
+	#include <afb/afb-service-itf.h>
+};
+
+void on_no_clients(std::string message)
+{
+	DiagnosticRequest* diag_req = configuration_t::instance().get_request_from_diagnostic_message(message);
+	if(diag_req != nullptr)
+	{
+		active_diagnostic_request_t* adr = configuration_t::instance().get_diagnostic_manager().find_recurring_request(diag_req);
+		if( adr != nullptr)
+			configuration_t::instance().get_diagnostic_manager().cleanup_request(adr, true);
+	}
+}
+
+int read(sd_event_source *s, int fd, uint32_t revents, void *userdata)
+{
+	can_signal_t* sig= (can_signal_t*)userdata;
+	if(sig->read_socket() != can_message_format_t::ERROR)
+		return 0;
+	return -1;
+}
+
+///******************************************************************************
+///
+///		Subscription and unsubscription
+///
+///*******************************************************************************/
+
+static int make_subscription_unsubscription(struct afb_req request, const std::string& sig_name, std::map<std::string, struct afb_event>& s, bool subscribe)
+{
+	/* Make the subscription or unsubscription to the event */
+	if (((subscribe ? afb_req_subscribe : afb_req_unsubscribe)(request, s[sig_name])) < 0)
+	{
+		ERROR(binder_interface, "%s: Operation goes wrong for signal: %s", __FUNCTION__, sig_name.c_str());
+		return 0;
+	}
+	return 1;
+}
+
+static int create_event_handle(const std::string& sig_name, std::map<std::string, struct afb_event>& s)
+{
+	s[sig_name] = afb_daemon_make_event(binder_interface->daemon, sig_name.c_str());
+	if (!afb_event_is_valid(s[sig_name]))
+	{
+		ERROR(binder_interface, "%s: Can't create an event for %s, something goes wrong.", __FUNCTION__, sig_name.c_str());
+		return 0;
+	}
+	return 1;
+}
+
+/// @brief Will determine if it is needed or not to create the event handle and checks it to be sure that
+/// we got a valid afb_event to get subscribe or unsubscribe. Then launch the subscription or unsubscription
+/// against the application framework using that event handle.
+static int subscribe_unsubscribe_signal(struct afb_req request, bool subscribe, const std::string& sig)
+{
+	int ret;
+
+	utils::signals_manager_t& sm = utils::signals_manager_t::instance();
+
+	std::lock_guard<std::mutex> subscribed_signals_lock(sm.get_subscribed_signals_mutex());
+	std::map<std::string, struct afb_event>& s = sm.get_subscribed_signals();
+	if (s.find(sig) != s.end())
+	{
+		if (!afb_event_is_valid(s[sig]) && !subscribe)
+		{
+			NOTICE(binder_interface, "%s: Event isn't valid, no need to unsubscribed.", __FUNCTION__);
+			ret = -1;
+		}
+		else
+		{
+			// Event it isn't valid annymore, recreate it
+			ret = create_event_handle(sig, s);
+		}
+	}
+	else
+	{
+		/* Event doesn't exist , so let's create it */
+		struct afb_event empty_event = {nullptr, nullptr};
+		s[sig] = empty_event;
+		ret = create_event_handle(sig, s);
+	}
+
+	// Check whether or not the event handler has been correctly created and
+	// make the subscription/unsubscription operation is so.
+	if (ret <= 0)
+		return ret;
+	return make_subscription_unsubscription(request, sig, s, subscribe);
+}
+
+///
+/// @brief subscribe to all signals in the vector signals
+///
+/// @param[in] afb_req request : contain original request use to subscribe or unsubscribe
+/// @param[in] subscribe boolean value used to chose between a subscription operation or an unsubscription
+/// @param[in] signals -  struct containing vectors with can_signal_t and diagnostic_messages to subscribe
+///
+/// @return Number of correctly subscribed signal
+///
+static int subscribe_unsubscribe_signals(struct afb_req request, bool subscribe, const struct utils::signals_found& signals)
+{
+	int ret,  rets = 0;
+
+	//TODO: Implement way to dynamically call the right function no matter
+	// how much signals types we have.
+	configuration_t& conf = configuration_t::instance();
+
+	for(const auto& sig : signals.diagnostic_messages)
+	{
+		diagnostic_manager_t& diag_m = conf.get_diagnostic_manager();
+		DiagnosticRequest* diag_req = conf.get_request_from_diagnostic_message(sig->get_name());
+
+		// If the requested diagnostic message isn't supported by the car then unsubcribe it
+		// no matter what we want, worse case will be a fail unsubscription but at least we don't
+		// poll a PID for nothing.
+		if(sig->get_supported() && subscribe)
+		{
+				float frequency = sig->get_frequency();
+				subscribe = diag_m.add_recurring_request(
+					diag_req, sig->get_name().c_str(), false, sig->get_decoder(), sig->get_callback(), (float)frequency);
+					//TODO: Adding callback requesting ignition status:	diag_req, sig.c_str(), false, diagnostic_message_t::decode_obd2_response, diagnostic_message_t::check_ignition_status, frequency);
+		}
+		else
+		{
+			diag_m.cleanup_request(
+				diag_m.find_recurring_request(diag_req), true);
+			WARNING(binder_interface, "%s: signal: %s isn't supported. Canceling operation.", __FUNCTION__, sig->get_name().c_str());
+			return -1;
+		}
+
+		ret = subscribe_unsubscribe_signal(request, subscribe, sig->get_name());
+		if(ret <= 0)
+			return ret;
+		rets++;
+		DEBUG(binder_interface, "%s: Signal: %s subscribed", __FUNCTION__, sig->get_name().c_str());
+	}
+
+	for(const auto& sig: signals.can_signals)
+	{
+		if(sig->create_rx_filter() <= 0 && 
+			subscribe_unsubscribe_signal(request, subscribe, sig->get_name()) <=0)
+		{
+			return -1;
+		}
+		struct sd_event_source* e_source;
+		sd_event_add_io(afb_daemon_get_event_loop(binder_interface->daemon), &e_source, sig->get_socket().socket(), EPOLLIN, read, sig);
+		rets++;
+		DEBUG(binder_interface, "%s: signal: %s subscribed", __FUNCTION__, sig->get_name().c_str());
+	}
+	return rets;
+}
+
+static const std::vector<std::string> parse_args_from_request(struct afb_req request, bool subscribe)
+{
+	int i, n;
+	std::vector<std::string> ret;
+	struct json_object *args, *a, *x;
+
+	/* retrieve signals to subscribe */
+	args = afb_req_json(request);
+	if (args == NULL || !json_object_object_get_ex(args, "event", &a))
+	{
+		ret.push_back("*");
+	}
+	else if (json_object_get_type(a) != json_type_array)
+	{
+		ret.push_back(json_object_get_string(a));
+	}
+	else
+	{
+		n = json_object_array_length(a);
+		for (i = 0 ; i < n ; i++)
+		{
+			x = json_object_array_get_idx(a, i);
+			ret.push_back(json_object_get_string(x));
+		}
+	}
+
+	return ret;
+}
+
+void subscribe(struct afb_req request)
+{
+	std::vector<std::string> args;
+	struct utils::signals_found sf;
+	int ok = 0, total = 0;
+	bool subscribe = true;
+
+	args = parse_args_from_request(request, subscribe);
+
+	for(const auto& sig: args)
+	{
+		openxc_DynamicField search_key = build_DynamicField(sig);
+		sf = utils::signals_manager_t::instance().find_signals(search_key);
+		total = (int)sf.can_signals.size() + (int)sf.diagnostic_messages.size();
+
+		if (sf.can_signals.empty() && sf.diagnostic_messages.empty())
+			NOTICE(binder_interface, "%s: No signal(s) found for %s.", __FUNCTION__, sig.c_str());
+		else
+			ok = subscribe_unsubscribe_signals(request, subscribe, sf);
+	}
+
+	NOTICE(binder_interface, "%s: Subscribed/unsubscribe correctly to %d/%d signal(s).", __FUNCTION__, ok, total);
+	if (ok > 0)
+		afb_req_success(request, NULL, NULL);
+	else
+		afb_req_fail(request, "error", NULL);
+}
+
+	void unsubscribe(struct afb_req request)
+{
+	parse_args_from_request(request, false);
+}
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