owntone-server/src/main.c

/*
 * Copyright (C) 2009-2011 Julien BLACHE <jb@jblache.org>
 *
 * Pieces from mt-daapd:
 * Copyright (C) 2003 Ron Pedde (ron@pedde.com)
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

#ifdef HAVE_CONFIG_H
# include <config.h>
#endif

#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>
#include <unistd.h>
#include <string.h>
#include <errno.h>
#include <fcntl.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <signal.h>
#include <limits.h>
#include <grp.h>
#include <stdint.h>

#ifdef HAVE_SIGNALFD
# include <sys/signalfd.h>
#else
# include <sys/time.h>
# include <sys/event.h>
#endif

#include <getopt.h>
#include <event2/event.h>
#ifdef HAVE_LIBEVENT_PTHREADS
# include <event2/thread.h>
#endif
#include <libavutil/avutil.h>
#include <libavutil/log.h>
#include <libavformat/avformat.h>
#include <libavfilter/avfilter.h>
#include <curl/curl.h>

#include <pthread.h>
#include <gcrypt.h>
GCRY_THREAD_OPTION_PTHREAD_IMPL;

#include "conffile.h"
#include "db.h"
#include "logger.h"
#include "misc.h"
#include "cache.h"
#include "httpd.h"
#include "mpd.h"
#include "mdns.h"
#include "remote_pairing.h"
#include "player.h"
#include "worker.h"
#include "library.h"
#ifdef LASTFM
# include "lastfm.h"
#endif

#define PIDFILE   STATEDIR "/run/" PACKAGE ".pid"
#define WEB_ROOT  DATADIR "/htdocs"

struct event_base *evbase_main;

static struct event *sig_event;
static int main_exit;

static void
version(void)
{
  fprintf(stdout, "%s %s\n", PACKAGE_NAME, PACKAGE_VERSION);
}

static void
usage(char *program)
{
  version();
  printf("\n");
  printf("Usage: %s [options]\n\n", program);
  printf("Options:\n");
  printf("  -d <number>    Log level (0-5)\n");
  printf("  -D <dom,dom..> Log domains\n");
  printf("  -c <file>      Use <file> as the configfile\n");
  printf("  -P <file>      Write PID to specified file\n");
  printf("  -f             Run in foreground\n");
  printf("  -b <id>        ffid to be broadcast\n");
  printf("  -v             Display version information\n");
  printf("  -w <directory> Use <directory> as the web root directory for serving static files\n");
  printf("\n\n");
  printf("Available log domains:\n");
  logger_domains();
  printf("\n\n");
}

static int
daemonize(bool background, char *pidfile)
{
  FILE *fp;
  pid_t childpid;
  pid_t pid_ret;
  int fd;
  int ret;
  char *runas;

  if (background)
    {
      fp = fopen(pidfile, "w");
      if (!fp)
	{
	  DPRINTF(E_LOG, L_MAIN, "Error opening pidfile (%s): %s\n", pidfile, strerror(errno));

	  return -1;
	}

      fd = open("/dev/null", O_RDWR, 0);
      if (fd < 0)
	{
	  DPRINTF(E_LOG, L_MAIN, "Error opening /dev/null: %s\n", strerror(errno));

	  fclose(fp);
	  return -1;
	}

      signal(SIGTTOU, SIG_IGN);
      signal(SIGTTIN, SIG_IGN);
      signal(SIGTSTP, SIG_IGN);

      childpid = fork();

      if (childpid > 0)
	exit(EXIT_SUCCESS);
      else if (childpid < 0)
	{
	  DPRINTF(E_FATAL, L_MAIN, "Fork failed: %s\n", strerror(errno));

	  close(fd);
	  fclose(fp);
	  return -1;
	}

      pid_ret = setsid();
      if (pid_ret == (pid_t) -1)
	{
	  DPRINTF(E_FATAL, L_MAIN, "setsid() failed: %s\n", strerror(errno));

	  close(fd);
	  fclose(fp);
	  return -1;
	}

      logger_detach();

      dup2(fd, STDIN_FILENO);
      dup2(fd, STDOUT_FILENO);
      dup2(fd, STDERR_FILENO);

      if (fd > 2)
	close(fd);

      ret = chdir("/");
      if (ret < 0)
        DPRINTF(E_WARN, L_MAIN, "chdir() failed: %s\n", strerror(errno));

      umask(0);

      fprintf(fp, "%d\n", getpid());
      fclose(fp);

      DPRINTF(E_DBG, L_MAIN, "PID: %d\n", getpid());
    }

  if (geteuid() == (uid_t) 0)
    {
      runas = cfg_getstr(cfg_getsec(cfg, "general"), "uid");

      ret = initgroups(runas, runas_gid);
      if (ret != 0)
	{
	  DPRINTF(E_FATAL, L_MAIN, "initgroups() failed: %s\n", strerror(errno));

	  return -1;
	}

      ret = setegid(runas_gid);
      if (ret != 0)
	{
	  DPRINTF(E_FATAL, L_MAIN, "setegid() failed: %s\n", strerror(errno));

	  return -1;
	}

      ret = seteuid(runas_uid);
      if (ret != 0)
	{
	  DPRINTF(E_FATAL, L_MAIN, "seteuid() failed: %s\n", strerror(errno));

	  return -1;
	}
    }

  return 0;
}

static int
register_services(char *ffid, bool no_web, bool no_rsp, bool no_daap, bool no_mpd)
{
  cfg_t *lib;
  cfg_t *mpd;
  char *libname;
  char *password;
  char *txtrecord[10];
  char records[9][128];
  int port;
  int mpd_port;
  uint32_t hash;
  int i;
  int ret;

  srand((unsigned int)time(NULL));

  lib = cfg_getsec(cfg, "library");

  libname = cfg_getstr(lib, "name");
  hash = djb_hash(libname, strlen(libname));

  for (i = 0; i < (sizeof(records) / sizeof(records[0])); i++)
    {
      memset(records[i], 0, 128);
      txtrecord[i] = records[i];
    }

  txtrecord[9] = NULL;

  snprintf(txtrecord[0], 128, "txtvers=1");
  snprintf(txtrecord[1], 128, "Database ID=%0X", hash);
  snprintf(txtrecord[2], 128, "Machine ID=%0X", hash);
  snprintf(txtrecord[3], 128, "Machine Name=%s", libname);
  snprintf(txtrecord[4], 128, "mtd-version=%s", VERSION);
  snprintf(txtrecord[5], 128, "iTSh Version=131073"); // iTunes 6.0.4
  snprintf(txtrecord[6], 128, "Version=196610");      // iTunes 6.0.4

  password = cfg_getstr(lib, "password");
  snprintf(txtrecord[7], 128, "Password=%s", (password) ? "true" : "false");

  if (ffid)
    snprintf(txtrecord[8], 128, "ffid=%s", ffid);
  else
    snprintf(txtrecord[8], 128, "ffid=%08x", rand());

  DPRINTF(E_INFO, L_MAIN, "Registering rendezvous names\n");

  port = cfg_getint(lib, "port");

  if (!no_web)
    {
      ret = mdns_register(libname, "_http._tcp", port, txtrecord);
      if (ret < 0)
	return ret;
    }

  // Register RSP service
  if (!no_rsp)
    {
      ret = mdns_register(libname, "_rsp._tcp", port, txtrecord);
      if (ret < 0)
	return ret;
    }

  // Register DAAP service
  if (!no_daap)
    {
      ret = mdns_register(libname, "_daap._tcp", port, txtrecord);
      if (ret < 0)
	return ret;
    }

  for (i = 0; i < (sizeof(records) / sizeof(records[0])); i++)
    {
      memset(records[i], 0, 128);
      txtrecord[i] = records[i];
    }

  // Register DACP service
  snprintf(txtrecord[0], 128, "txtvers=1");
  snprintf(txtrecord[1], 128, "Ver=131077");   // iTunes 12.7.4
  snprintf(txtrecord[2], 128, "DbId=1");       // Must be the id of our database, i.e. 1
  snprintf(txtrecord[3], 128, "OSsi=0x2012E"); // Magic number! Yay!
  txtrecord[4] = NULL;

  // The group name for the dacp service must be iTunes_Ctrl_(libhash),
  // otherwise at least my Sony speaker won't use the service.

  // Use as scratch space for the hash
  snprintf(records[4], 128, "iTunes_Ctrl_%016" PRIX64, libhash);

  ret = mdns_register(records[4], "_dacp._tcp", port, txtrecord);
  if (ret < 0)
    return ret;

  for (i = 0; i < (sizeof(records) / sizeof(records[0])); i++)
    {
      memset(records[i], 0, 128);
      txtrecord[i] = records[i];
    }

  // Register touch-able service, for Remote.app
  snprintf(txtrecord[0], 128, "txtvers=1");
  snprintf(txtrecord[1], 128, "DbId=%016" PRIX64, libhash);
  snprintf(txtrecord[2], 128, "DvTy=iTunes");
  snprintf(txtrecord[3], 128, "DvSv=2306");  // Magic number! Yay!
  snprintf(txtrecord[4], 128, "Ver=131073"); // iTunes 6.0.4
  snprintf(txtrecord[5], 128, "OSsi=0x1F5"); // Magic number! Yay!
  snprintf(txtrecord[6], 128, "CtlN=%s", libname);
  txtrecord[7] = NULL;

  // The group name for the touch-able service advertising is a 64bit hash
  // but is different from the DbId in iTunes. For now we'll use a hash of
  // the library name for both, and we'll change that if needed.

  // Use as scratch space for the hash
  snprintf(records[7], 128, "%016" PRIX64, libhash);

  ret = mdns_register(records[7], "_touch-able._tcp", port, txtrecord);
  if (ret < 0)
    return ret;

  // Register MPD serivce
  mpd = cfg_getsec(cfg, "mpd");
  mpd_port = cfg_getint(mpd, "port");
  if (!no_mpd && mpd_port > 0)
    {
      ret = mdns_register(libname, "_mpd._tcp", mpd_port, NULL);
            if (ret < 0)
      	return ret;
    }

  return 0;
}


#ifdef HAVE_SIGNALFD
static void
signal_signalfd_cb(int fd, short event, void *arg)
{
  struct signalfd_siginfo info;
  int status;

  while (read(fd, &info, sizeof(struct signalfd_siginfo)) > 0)
    {
      switch (info.ssi_signo)
	{
	  case SIGCHLD:
	    DPRINTF(E_LOG, L_MAIN, "Got SIGCHLD\n");

	    while (waitpid(-1, &status, WNOHANG) > 0)
	      /* Nothing. */ ;
	    break;

	  case SIGINT:
	  case SIGTERM:
	    DPRINTF(E_LOG, L_MAIN, "Got SIGTERM or SIGINT\n");

	    main_exit = 1;
	    break;

	  case SIGHUP:
	    DPRINTF(E_LOG, L_MAIN, "Got SIGHUP\n");

	    if (!main_exit)
	      logger_reinit();
	    break;
	}
    }

  if (main_exit)
    event_base_loopbreak(evbase_main);
  else
    event_add(sig_event, NULL);
}

#else

static void
signal_kqueue_cb(int fd, short event, void *arg)
{
  struct timespec ts;
  struct kevent ke;
  int status;

  ts.tv_sec = 0;
  ts.tv_nsec = 0;

  while (kevent(fd, NULL, 0, &ke, 1, &ts) > 0)
    {
      switch (ke.ident)
	{
	  case SIGCHLD:
	    DPRINTF(E_LOG, L_MAIN, "Got SIGCHLD\n");

	    while (waitpid(-1, &status, WNOHANG) > 0)
	      /* Nothing. */ ;
	    break;

	  case SIGINT:
	  case SIGTERM:
	    DPRINTF(E_LOG, L_MAIN, "Got SIGTERM or SIGINT\n");

	    main_exit = 1;
	    break;

	  case SIGHUP:
	    DPRINTF(E_LOG, L_MAIN, "Got SIGHUP\n");

	    if (!main_exit)
	      logger_reinit();
	    break;
	}
    }

  if (main_exit)
    event_base_loopbreak(evbase_main);
  else
    event_add(sig_event, NULL);
}
#endif

#if (LIBAVCODEC_VERSION_MAJOR < 58) || ((LIBAVCODEC_VERSION_MAJOR == 58) && (LIBAVCODEC_VERSION_MINOR < 18))
static int
ffmpeg_lockmgr(void **pmutex, enum AVLockOp op)
{
  switch (op)
    {
      case AV_LOCK_CREATE:
	*pmutex = malloc(sizeof(pthread_mutex_t));
	if (!*pmutex)
	  return 1;
        CHECK_ERR(L_MAIN, mutex_init(*pmutex));
	return 0;

      case AV_LOCK_OBTAIN:
        CHECK_ERR(L_MAIN, pthread_mutex_lock(*pmutex));
	return 0;

      case AV_LOCK_RELEASE:
        CHECK_ERR(L_MAIN, pthread_mutex_unlock(*pmutex));
	return 0;

      case AV_LOCK_DESTROY:
	CHECK_ERR(L_MAIN, pthread_mutex_destroy(*pmutex));
	free(*pmutex);
        *pmutex = NULL;

	return 0;
    }

  return 1;
}
#endif

int
main(int argc, char **argv)
{
  int option;
  char *configfile;
  bool background;
  bool mdns_no_rsp;
  bool mdns_no_daap;
  bool mdns_no_cname;
  bool mdns_no_web;
  bool mdns_no_mpd;
  int loglevel;
  char *logdomains;
  char *logfile;
  char *ffid;
  char *pidfile;
  char *webroot;
  char **buildopts;
  const char *av_version;
  const char *gcry_version;
  sigset_t sigs;
  int sigfd;
#ifdef HAVE_KQUEUE
  struct kevent ke_sigs[4];
#endif
  int i;
  int ret;

  struct option option_map[] =
    {
      { "ffid",         1, NULL, 'b' },
      { "debug",        1, NULL, 'd' },
      { "logdomains",   1, NULL, 'D' },
      { "foreground",   0, NULL, 'f' },
      { "config",       1, NULL, 'c' },
      { "pidfile",      1, NULL, 'P' },
      { "version",      0, NULL, 'v' },
      { "webroot",      1, NULL, 'w' },

      { "mdns-no-rsp",  0, NULL, 512 },
      { "mdns-no-daap", 0, NULL, 513 },
      { "mdns-no-cname",0, NULL, 514 },
      { "mdns-no-web",  0, NULL, 515 },

      { NULL,           0, NULL, 0 }
    };

  configfile = CONFFILE;
  pidfile = PIDFILE;
  webroot = WEB_ROOT;
  loglevel = -1;
  logdomains = NULL;
  logfile = NULL;
  background = true;
  ffid = NULL;
  mdns_no_rsp = false;
  mdns_no_daap = false;
  mdns_no_cname = false;
  mdns_no_web = false;

  while ((option = getopt_long(argc, argv, "D:d:c:P:fb:vw:", option_map, NULL)) != -1)
    {
      switch (option)
	{
	  case 512:
	    mdns_no_rsp = true;
	    break;

	  case 513:
	    mdns_no_daap = true;
	    break;

	  case 514:
	    mdns_no_cname = true;
	    break;

	  case 515:
	    mdns_no_web = true;
	    break;

	  case 'b':
	    ffid = optarg;
	    break;

	  case 'd':
	    ret = safe_atoi32(optarg, &option);
	    if (ret < 0)
	      fprintf(stderr, "Error: loglevel must be an integer in '-d %s'\n", optarg);
	    else
	      loglevel = option;
	    break;

	  case 'D':
	    logdomains = optarg;
	    break;

	  case 'f':
	    background = false;
	    break;

	  case 'c':
	    configfile = optarg;
	    break;

	  case 'P':
	    pidfile = optarg;
	    break;

	  case 'v':
	    version();
	    return EXIT_SUCCESS;
	    break;

	  case 'w':
	    webroot = optarg;
	    break;

	  default:
	    usage(argv[0]);
	    return EXIT_FAILURE;
	    break;
	}
    }

  ret = logger_init(NULL, NULL, (loglevel < 0) ? E_LOG : loglevel);
  if (ret != 0)
    {
      fprintf(stderr, "Could not initialize log facility\n");

      return EXIT_FAILURE;
    }

  ret = conffile_load(configfile);
  if (ret != 0)
    {
      DPRINTF(E_FATAL, L_MAIN, "Config file errors; please fix your config\n");

      logger_deinit();
      return EXIT_FAILURE;
    }

  logger_deinit();

  /* Reinit log facility with configfile values */
  if (loglevel < 0)
    loglevel = cfg_getint(cfg_getsec(cfg, "general"), "loglevel");

  logfile = cfg_getstr(cfg_getsec(cfg, "general"), "logfile");

  ret = logger_init(logfile, logdomains, loglevel);
  if (ret != 0)
    {
      fprintf(stderr, "Could not reinitialize log facility with config file settings\n");

      conffile_unload();
      return EXIT_FAILURE;
    }

  /* Set up libevent logging callback */
  event_set_log_callback(logger_libevent);

  DPRINTF(E_LOG, L_MAIN, "Forked Media Server Version %s taking off\n", VERSION);

  DPRINTF(E_LOG, L_MAIN, "Built with:\n");
  buildopts = buildopts_get();
  for (i = 0; buildopts[i]; i++)
    {
      DPRINTF(E_LOG, L_MAIN, "- %s\n", buildopts[i]);
    }

#if HAVE_DECL_AV_VERSION_INFO
  av_version = av_version_info();
#else
  av_version = "(unknown version)";
#endif

#ifdef HAVE_FFMPEG
  DPRINTF(E_INFO, L_MAIN, "Initialized with ffmpeg %s\n", av_version);
#else
  DPRINTF(E_INFO, L_MAIN, "Initialized with libav %s\n", av_version);
#endif

// The following was deprecated with ffmpeg 4.0 = avcodec 58.18, avformat 58.12, avfilter 7.16
#if (LIBAVCODEC_VERSION_MAJOR < 58) || ((LIBAVCODEC_VERSION_MAJOR == 58) && (LIBAVCODEC_VERSION_MINOR < 18))
  ret = av_lockmgr_register(ffmpeg_lockmgr);
  if (ret < 0)
    {
      DPRINTF(E_FATAL, L_MAIN, "Could not register ffmpeg lock manager callback\n");

      ret = EXIT_FAILURE;
      goto ffmpeg_init_fail;
    }
#endif
#if (LIBAVFORMAT_VERSION_MAJOR < 58) || ((LIBAVFORMAT_VERSION_MAJOR == 58) && (LIBAVFORMAT_VERSION_MINOR < 12))
  av_register_all();
#endif
#if (LIBAVFILTER_VERSION_MAJOR < 7) || ((LIBAVFILTER_VERSION_MAJOR == 7) && (LIBAVFILTER_VERSION_MINOR < 16))
  avfilter_register_all();
#endif

#if HAVE_DECL_AVFORMAT_NETWORK_INIT
  avformat_network_init();
#endif
  av_log_set_callback(logger_ffmpeg);

  /* Initialize libcurl */
  curl_global_init(CURL_GLOBAL_DEFAULT);

  /* Initialize libgcrypt */
  gcry_control(GCRYCTL_SET_THREAD_CBS, &gcry_threads_pthread);

  gcry_version = gcry_check_version(GCRYPT_VERSION);
  if (!gcry_version)
    {
      DPRINTF(E_FATAL, L_MAIN, "libgcrypt version mismatch\n");

      ret = EXIT_FAILURE;
      goto gcrypt_init_fail;
    }

  /* We aren't handling anything sensitive, so give up on secure
   * memory, which is a scarce system resource.
   */
  gcry_control(GCRYCTL_DISABLE_SECMEM, 0);

  gcry_control(GCRYCTL_INITIALIZATION_FINISHED, 0);

  DPRINTF(E_DBG, L_MAIN, "Initialized with gcrypt %s\n", gcry_version);

  /* Block signals for all threads except the main one */
  sigemptyset(&sigs);
  sigaddset(&sigs, SIGINT);
  sigaddset(&sigs, SIGHUP);
  sigaddset(&sigs, SIGCHLD);
  sigaddset(&sigs, SIGTERM);
  sigaddset(&sigs, SIGPIPE);
  ret = pthread_sigmask(SIG_BLOCK, &sigs, NULL);
  if (ret != 0)
    {
      DPRINTF(E_LOG, L_MAIN, "Error setting signal set\n");

      ret = EXIT_FAILURE;
      goto signal_block_fail;
    }

  /* Daemonize and drop privileges */
  ret = daemonize(background, pidfile);
  if (ret < 0)
    {
      DPRINTF(E_LOG, L_MAIN, "Could not initialize server\n");

      ret = EXIT_FAILURE;
      goto daemon_fail;
    }

  /* Initialize event base (after forking) */
  CHECK_NULL(L_MAIN, evbase_main = event_base_new());

#ifdef HAVE_LIBEVENT_PTHREADS
  CHECK_ERR(L_MAIN, evthread_use_pthreads());
#endif

  DPRINTF(E_LOG, L_MAIN, "mDNS init\n");
  ret = mdns_init();
  if (ret != 0)
    {
      DPRINTF(E_FATAL, L_MAIN, "mDNS init failed\n");

      ret = EXIT_FAILURE;
      goto mdns_fail;
    }

  /* Initialize the database before starting */
  DPRINTF(E_INFO, L_MAIN, "Initializing database\n");
  ret = db_init();
  if (ret < 0)
    {
      DPRINTF(E_FATAL, L_MAIN, "Database init failed\n");

      ret = EXIT_FAILURE;
      goto db_fail;
    }

  /* Open a DB connection for the main thread */
  ret = db_perthread_init();
  if (ret < 0)
    {
      DPRINTF(E_FATAL, L_MAIN, "Could not perform perthread DB init for main\n");

      ret = EXIT_FAILURE;
      goto db_fail;
    }

  /* Spawn worker thread */
  ret = worker_init();
  if (ret != 0)
    {
      DPRINTF(E_FATAL, L_MAIN, "Worker thread failed to start\n");

      ret = EXIT_FAILURE;
      goto worker_fail;
    }

  /* Spawn cache thread */
  ret = cache_init();
  if (ret != 0)
    {
      DPRINTF(E_FATAL, L_MAIN, "Cache thread failed to start\n");

      ret = EXIT_FAILURE;
      goto cache_fail;
    }

  /* Spawn library scan thread */
  ret = library_init();
  if (ret != 0)
    {
      DPRINTF(E_FATAL, L_MAIN, "Library thread failed to start\n");

      ret = EXIT_FAILURE;
      goto library_fail;
    }

  /* Spawn player thread */
  ret = player_init();
  if (ret != 0)
    {
      DPRINTF(E_FATAL, L_MAIN, "Player thread failed to start\n");

      ret = EXIT_FAILURE;
      goto player_fail;
    }

  /* Spawn HTTPd thread */
  ret = httpd_init(webroot);
  if (ret != 0)
    {
      DPRINTF(E_FATAL, L_MAIN, "HTTPd thread failed to start\n");

      ret = EXIT_FAILURE;
      goto httpd_fail;
    }

#ifdef MPD
  /* Spawn MPD thread */
  ret = mpd_init();
  if (ret != 0)
    {
      DPRINTF(E_FATAL, L_MAIN, "MPD thread failed to start\n");

      ret = EXIT_FAILURE;
      goto mpd_fail;
    }
  mdns_no_mpd = false;
#else
  mdns_no_mpd = true;
#endif

#ifdef LASTFM
  lastfm_init();
#endif

  /* Start Remote pairing service */
  ret = remote_pairing_init();
  if (ret != 0)
    {
      DPRINTF(E_FATAL, L_MAIN, "Remote pairing service failed to start\n");

      ret = EXIT_FAILURE;
      goto remote_fail;
    }

  /* Register mDNS services */
  ret = register_services(ffid, mdns_no_web, mdns_no_rsp, mdns_no_daap, mdns_no_mpd);
  if (ret < 0)
    {
      ret = EXIT_FAILURE;
      goto mdns_reg_fail;
    }

  /* Register this CNAME with mDNS for OAuth */
  if (!mdns_no_cname)
    mdns_cname("forked-daapd.local");

#ifdef HAVE_SIGNALFD
  /* Set up signal fd */
  sigfd = signalfd(-1, &sigs, SFD_NONBLOCK | SFD_CLOEXEC);
  if (sigfd < 0)
    {
      DPRINTF(E_FATAL, L_MAIN, "Could not setup signalfd: %s\n", strerror(errno));

      ret = EXIT_FAILURE;
      goto signalfd_fail;
    }

  sig_event = event_new(evbase_main, sigfd, EV_READ, signal_signalfd_cb, NULL);
#else
  sigfd = kqueue();
  if (sigfd < 0)
    {
      DPRINTF(E_FATAL, L_MAIN, "Could not setup kqueue: %s\n", strerror(errno));

      ret = EXIT_FAILURE;
      goto signalfd_fail;
    }

  EV_SET(&ke_sigs[0], SIGINT, EVFILT_SIGNAL, EV_ADD, 0, 0, NULL);
  EV_SET(&ke_sigs[1], SIGTERM, EVFILT_SIGNAL, EV_ADD, 0, 0, NULL);
  EV_SET(&ke_sigs[2], SIGHUP, EVFILT_SIGNAL, EV_ADD, 0, 0, NULL);
  EV_SET(&ke_sigs[3], SIGCHLD, EVFILT_SIGNAL, EV_ADD, 0, 0, NULL);

  ret = kevent(sigfd, ke_sigs, 4, NULL, 0, NULL);
  if (ret < 0)
    {
      DPRINTF(E_FATAL, L_MAIN, "Could not register signal events: %s\n", strerror(errno));

      ret = EXIT_FAILURE;
      goto signalfd_fail;
    }

  sig_event = event_new(evbase_main, sigfd, EV_READ, signal_kqueue_cb, NULL);
#endif
  if (!sig_event)
    {
      DPRINTF(E_FATAL, L_MAIN, "Could not create signal event\n");

      ret = EXIT_FAILURE;
      goto sig_event_fail;
    }

  event_add(sig_event, NULL);

  /* Run the loop */
  event_base_dispatch(evbase_main);

  DPRINTF(E_LOG, L_MAIN, "Stopping gracefully\n");
  ret = EXIT_SUCCESS;

  event_free(sig_event);

  /*
   * On a clean shutdown, bring mDNS down first to give a chance
   * to the clients to perform a clean shutdown on their end
   */
  DPRINTF(E_LOG, L_MAIN, "mDNS deinit\n");
  mdns_deinit();

 sig_event_fail:
 signalfd_fail:
 mdns_reg_fail:
  DPRINTF(E_LOG, L_MAIN, "Remote pairing deinit\n");
  remote_pairing_deinit();

 remote_fail:
#ifdef MPD
  DPRINTF(E_LOG, L_MAIN, "MPD deinit\n");
  mpd_deinit();

 mpd_fail:
#endif
  DPRINTF(E_LOG, L_MAIN, "HTTPd deinit\n");
  httpd_deinit();

 httpd_fail:
  DPRINTF(E_LOG, L_MAIN, "Player deinit\n");
  player_deinit();

 player_fail:
  DPRINTF(E_LOG, L_MAIN, "Library scanner deinit\n");
  library_deinit();

 library_fail:
  DPRINTF(E_LOG, L_MAIN, "Cache deinit\n");
  cache_deinit();

 cache_fail:
  DPRINTF(E_LOG, L_MAIN, "Worker deinit\n");
  worker_deinit();

 worker_fail:
  DPRINTF(E_LOG, L_MAIN, "Database deinit\n");
  db_perthread_deinit();
  db_deinit();

 db_fail:
  if (ret == EXIT_FAILURE)
    {
      DPRINTF(E_LOG, L_MAIN, "mDNS deinit\n");
      mdns_deinit();
    }

 mdns_fail:
  event_base_free(evbase_main);

 daemon_fail:
  if (background)
    {
      ret = seteuid(0);
      if (ret < 0)
	DPRINTF(E_LOG, L_MAIN, "seteuid() failed: %s\n", strerror(errno));
      else
	{
	  ret = unlink(pidfile);
	  if (ret < 0)
	    DPRINTF(E_LOG, L_MAIN, "Could not unlink PID file %s: %s\n", pidfile, strerror(errno));
	}
    }

 signal_block_fail:
 gcrypt_init_fail:
  curl_global_cleanup();
#if HAVE_DECL_AVFORMAT_NETWORK_INIT
  avformat_network_deinit();
#endif

#if (LIBAVCODEC_VERSION_MAJOR < 58) || ((LIBAVCODEC_VERSION_MAJOR == 58) && (LIBAVCODEC_VERSION_MINOR < 18))
  av_lockmgr_register(NULL);
 ffmpeg_init_fail:
#endif

  DPRINTF(E_LOG, L_MAIN, "Exiting.\n");
  conffile_unload();
  logger_deinit();

  return ret;
}