/* Rate-limiting hook. * * Author: Steffen Vogel * SPDX-FileCopyrightText: 2014-2023 Institute for Automation of Complex Power Systems, RWTH Aachen University * SPDX-License-Identifier: Apache-2.0 */ #include #include #include #include namespace villas { namespace node { void LimitRateHook::parse(json_t *json) { int ret; json_error_t err; assert(state != State::STARTED); double rate; const char *m = nullptr; Hook::parse(json); ret = json_unpack_ex(json, &err, 0, "{ s: F, s?: s }", "rate", &rate, "mode", &m); if (ret) throw ConfigError(json, err, "node-config-hook-limit_rate"); if (m) { if (!strcmp(m, "origin")) mode = LIMIT_RATE_ORIGIN; else if (!strcmp(m, "received")) mode = LIMIT_RATE_RECEIVED; else if (!strcmp(m, "local")) mode = LIMIT_RATE_LOCAL; else throw ConfigError(json, "node-config-hook-limit_rate-mode", "Invalid value '{}' for setting 'mode'", m); } deadtime = 1.0 / rate; state = State::PARSED; } Hook::Reason LimitRateHook::process(struct Sample *smp) { assert(state == State::STARTED); timespec next; switch (mode) { case LIMIT_RATE_LOCAL: next = time_now(); break; case LIMIT_RATE_ORIGIN: next = smp->ts.origin; break; case LIMIT_RATE_RECEIVED: next = smp->ts.received; break; } if (time_delta(&last, &next) < deadtime) return Hook::Reason::SKIP_SAMPLE; last = next; return Reason::OK; } // Register hook static char n[] = "limit_rate"; static char d[] = "Limit sending rate"; static HookPlugin p; } // namespace node } // namespace villas