leviathan_service.cpp

#include "leviathan_service.hpp"
#include "constants.h"  // #defines
#include "cpu_temperature_monitor.hpp"
#include "kraken_driver.hpp"
#include "leviathan_config.hpp"

#include <chrono>
#include <fstream>
#include <glog/logging.h>
#include <limits>
#include <thread>

#include <signal.h>
#include <stdio.h>
#include <string.h>
#include <sys/stat.h>
#include <time.h>
#include <unistd.h>

using namespace std::chrono_literals;

// Global kill all armed when SIGTERM is detected
volatile sig_atomic_t done = 0;
void                  term(int signum) { done = 1; }

/** *********** Private Interface ************** */

bool detect_kraken(libusb_device *device) {
  struct libusb_device_descriptor desc = {0};
  int err = libusb_get_device_descriptor(device, &desc);
  if (err != 0) {
    LOG(ERROR) << "Failed to get descriptor for generic device: "
               << libusb_error_name(err);
    return false;
  }
  return desc.idVendor == KRAKEN_X61_VENDOR
         && desc.idProduct == KRAKEN_X61_PRODUCT;
}

uint32_t next_speed(const std::map<int32_t, LineFunction> &fan_profile,
                    const uint32_t                         current_temp) {
  const auto slopeFn = fan_profile.upper_bound(current_temp)->second;
  return slopeFn(current_temp);
}

int file_is_modified(const char *path, time_t oldMTime) {
  struct stat file_stat;
  int         err = stat(path, &file_stat);
  LOG_IF(FATAL, err != 0) << "Error when attempting to stat " << path;
  return file_stat.st_mtime > oldMTime;
}

void update_conky_file(std::ostream &     ostream,
                       const std::string &serial,
                       const uint32_t     fan_speed,
                       const uint32_t     pump_speed,
                       const uint32_t     water_temp) {
  std::stringstream ss;
  ss << "Kraken Serial: " << serial << std::endl;
  ss << "Fan Speed: " << fan_speed << std::endl;
  ss << "Pump Speed: " << pump_speed << std::endl;
  ss << "Water Temp: " << water_temp << std::endl;
  ostream.seekp(0);
  ostream << ss.str();
}

/** *********** Public Interface ************** */

libusb_device *leviathan_init(libusb_device **devices, ssize_t num_devices) {
  libusb_device *kraken_device = NULL;
  for (auto i = 0u; i < num_devices; ++i) {
    if (detect_kraken(devices[i])) {
      kraken_device = devices[i];
      break;
    }
  }
  return kraken_device;
}

void leviathan_start(libusb_device *kraken_device) {
  // Init Kraken, display diagnostics
  auto kd = std::make_unique<KrakenDriver>(kraken_device);
  LOG(INFO) << "Kraken Driver Initialized";
  LOG(INFO) << "Kraken Serial No: " << kd->getSerialNumber();

  // The following two lines throw/crash on config error
  CpuTemperatureMonitor cpu_temp_mon;
  auto                  config_opts = parse_config_file(kDefaultConfigFile);
  std::ofstream         conky_oss(config_opts.conky_file_);

  // Local variables for state management
  uint32_t cpu_temp           = 0;
  uint32_t liquid_temp        = 0;
  uint32_t old_fan_speed      = 0;  // Take first reported value as
  uint32_t old_pump_speed     = 0;  // .. an update
  time_t   last_time_modified = std::numeric_limits<time_t>::min();

  // Init signal handler
  struct sigaction action;
  memset(&action, 0, sizeof(struct sigaction));
  action.sa_handler = term;
  sigaction(SIGTERM, &action, NULL);
  sigaction(SIGQUIT, &action, NULL);
  sigaction(SIGINT, &action, NULL);

  // Main program loop
  // 1. Update config_options if config file was edited
  // 2. Update color according to the given settings
  // 3. Read CPU and liquid temperatures
  // 4. Set fan/pump speed according to temp and given parameters
  // 5. Sleep for the defined interval and repeat
  while (!done) {
    // Grab latest parameters, if they've been changed
    if (file_is_modified(kDefaultConfigFile, last_time_modified)) {
      LOG(INFO)
        << "Detected modifications to config file, updating preferences...";
      config_opts        = parse_config_file(kDefaultConfigFile);
      last_time_modified = time(0);
    }

    // Update color, which also provides the liquid temp in case it's needed.
    kd->setColor(config_opts.main_color_);
    auto update = kd->sendColorUpdate();

    // Grab latest cpu and liquid temperatures
    cpu_temp    = cpu_temp_mon.getPackageIdTemperature();
    liquid_temp = update.find("liquid_temperature")->second;

    // Based on parameters and current temp, set desired fan and pump speeds
    uint32_t next_fan, next_pump;
    if (config_opts.temp_source_ == TempSource::LIQUID) {
      next_fan  = next_speed(config_opts.fan_profile_, liquid_temp);
      next_pump = next_speed(config_opts.pump_profile_, liquid_temp);
      VLOG(2) << "Current liquid temperature: " << liquid_temp << "C";
    } else {
      next_fan  = next_speed(config_opts.fan_profile_, cpu_temp);
      next_pump = next_speed(config_opts.pump_profile_, cpu_temp);
      VLOG(2) << "Current CPU temperature: " << cpu_temp << "C";
    }
    // Step down: If we are decreasing fan/pump speed, do it slowly
    if (next_fan < old_fan_speed) {
      next_fan = old_fan_speed - 5;
    }
    if (next_pump < old_pump_speed) {
      next_pump = old_pump_speed - 5;
    }
    VLOG(2) << "Setting fan speed: " << next_fan;
    VLOG(2) << "Setting pump speeds: " << next_pump;
    kd->setFanSpeed(next_fan);
    kd->setPumpSpeed(next_pump);
    update = kd->sendSpeedUpdate();
    if (update.empty() == true) {
      LOG(WARNING) << "Bad update detected, attempting reconnection...";
      // NOTE: Must ensure that destructor of old object pointed to by kd
      // is cleaned up before reassignment to a new instance of kraken
      // driver. i.e. only one can be alive at any given time.
      kd.reset(nullptr);
      std::this_thread::sleep_for(5s);
      kd.reset(new KrakenDriver(kraken_device));
    }

    if (next_fan != old_fan_speed || next_pump != old_pump_speed) {
      const auto fan_speed  = update.find("fan_speed")->second;
      const auto pump_speed = update.find("pump_speed")->second;
      LOG(INFO) << "Changed fan speed to " << fan_speed << "rpm, pump speed to "
                << pump_speed << "rpm, with fan percentage at " << next_fan
                << ", with pump percentage at " << next_pump
                << ", current CPU temperature at " << cpu_temp << "C"
                << ", and current liquid temperature at " << liquid_temp << "C";
      update_conky_file(conky_oss, kd->getSerialNumber(), fan_speed, pump_speed,
                        liquid_temp);
      old_fan_speed  = next_fan;
      old_pump_speed = next_pump;
    }

    std::this_thread::sleep_for(
      std::chrono::milliseconds(config_opts.interval_));
  }

  kd.reset(nullptr);
}