VILLASnode/lib/hook.cpp

/** Hook-releated functions.
 *
 * @author Steffen Vogel <post@steffenvogel.de>
 * @copyright 2014-2022, Institute for Automation of Complex Power Systems, EONERC
 * @license Apache 2.0
 *********************************************************************************/

#include <cstring>
#include <cmath>

#include <villas/timing.hpp>
#include <villas/node/config.hpp>
#include <villas/hook.hpp>
#include <villas/node/exceptions.hpp>
#include <villas/path.hpp>
#include <villas/utils.hpp>
#include <villas/node.hpp>

const char *hook_reasons[] = {
	"ok", "error", "skip-sample", "stop-processing"
};

using namespace villas;
using namespace villas::node;

Hook::Hook(Path *p, Node *n, int fl, int prio, bool en) :
	logger(logging.get("hook")),
	factory(nullptr),
	state(fl & (int) Hook::Flags::BUILTIN
		? State::CHECKED
		: State::INITIALIZED), /* We dont need to parse builtin hooks. */
	flags(fl),
	priority(prio),
	enabled(en),
	path(p),
	node(n),
	config(nullptr)
{ }

void Hook::prepare(SignalList::Ptr sigs)
{
	assert(state == State::CHECKED);

	signals = sigs->clone();

	prepare();

	state = State::PREPARED;
}

void Hook::parse(json_t *json)
{
	int ret;
	json_error_t err;

	assert(state != State::STARTED);

	int prio = -1;
	int en = -1;

	ret = json_unpack_ex(json, &err, 0, "{ s?: i, s?: b }",
		"priority", &prio,
		"enabled", &en
	);
	if (ret)
		throw ConfigError(json, err, "node-config-hook");

	if (prio >= 0)
		priority = prio;

	if (en >= 0)
		enabled = en;

	config = json;

	state = State::PARSED;
}

void SingleSignalHook::parse(json_t *json)
{
	int ret;

	json_error_t err;
	json_t *json_signal;

	Hook::parse(json);

	ret = json_unpack_ex(json, &err, 0, "{ s: o }",
		"signal", &json_signal
	);
	if (ret)
		throw ConfigError(json, err, "node-config-hook");

	if (!json_is_string(json_signal))
		throw ConfigError(json_signal, "node-config-hook-signals", "Invalid value for setting 'signal'");

	signalName = json_string_value(json_signal);
}


void SingleSignalHook::prepare()
{
	Hook::prepare();

	/* Setup mask */
	int index = signals->getIndexByName(signalName.c_str());
	if (index < 0)
		throw RuntimeError("Failed to find signal {}", signalName);

	signalIndex = (unsigned) index;
}

/* Multi Signal Hook */

void MultiSignalHook::parse(json_t *json)
{
	int ret;
	size_t i;

	json_error_t err;
	json_t *json_signals = nullptr;
	json_t *json_signal = nullptr;

	Hook::parse(json);

	ret = json_unpack_ex(json, &err, 0, "{ s?: o, s?: o }",
		"signals", &json_signals,
		"signal", &json_signal
	);
	if (ret)
		throw ConfigError(json, err, "node-config-hook");

	if (json_signals) {
		if (!json_is_array(json_signals))
			throw ConfigError(json_signals, "node-config-hook-signals", "Setting 'signals' must be a list of signal names");

		json_array_foreach(json_signals, i, json_signal) {
			if (!json_is_string(json_signal))
				throw ConfigError(json_signal, "node-config-hook-signals", "Invalid value for setting 'signals'");

			const char *name = json_string_value(json_signal);

			signalNames.push_back(name);
		}
	}
	else if (json_signal) {
		if (!json_is_string(json_signal))
			throw ConfigError(json_signal, "node-config-hook-signals", "Invalid value for setting 'signals'");

		const char *name = json_string_value(json_signal);

		signalNames.push_back(name);
	}
	else
		throw ConfigError(json, "node-config-hook-signals", "Missing 'signals' setting");
}


void MultiSignalHook::prepare()
{
	Hook::prepare();

	for (const auto &signalName : signalNames) {
		int index = signals->getIndexByName(signalName.c_str());
		if (index < 0)
			throw RuntimeError("Failed to find signal {}", signalName);

		signalIndices.push_back(index);
	}
}

void MultiSignalHook::check()
{
	Hook::check();

	if (signalNames.size() == 0)
		throw RuntimeError("At least a single signal must be provided");
}