text: /*
   * This file Copyright (C) Mnemosyne LLC
   *
   * This program is free software; you can redistribute it and/or modify
   * it under the terms of the GNU General Public License version 2
   * as published by the Free Software Foundation.
   *
   * http://www.gnu.org/licenses/old-licenses/gpl-2.0.html
   *
   * $Id: daemon.c 13625 2012-12-05 17:29:46Z jordan $
   */
  
  #include <errno.h>
  #include <stdio.h> /* printf */
  #include <stdlib.h> /* exit, atoi */
  
  #include <fcntl.h> /* open */
  #include <signal.h>
  #ifdef HAVE_SYSLOG
  #include <syslog.h>
  #endif
  #include <unistd.h> /* daemon */
  
  #include <event2/buffer.h>
  
  #include <libtransmission/transmission.h>
  #include <libtransmission/bencode.h>
  #include <libtransmission/tr-getopt.h>
  #include <libtransmission/utils.h>
  #include <libtransmission/version.h>
  
  #include "watch.h"
  
  #define MY_NAME "transmission-daemon"
  
  #define PREF_KEY_DIR_WATCH          "watch-dir"
  #define PREF_KEY_DIR_WATCH_ENABLED  "watch-dir-enabled"
  #define PREF_KEY_PIDFILE            "pidfile"
  
  #define MEM_K 1024
  #define MEM_K_STR "KiB"
  #define MEM_M_STR "MiB"
  #define MEM_G_STR "GiB"
  #define MEM_T_STR "TiB"
  
  #define DISK_K 1000
  #define DISK_B_STR  "B"
  #define DISK_K_STR "kB"
  #define DISK_M_STR "MB"
  #define DISK_G_STR "GB"
  #define DISK_T_STR "TB"
  
  #define SPEED_K 1000
  #define SPEED_B_STR  "B/s"
  #define SPEED_K_STR "kB/s"
  #define SPEED_M_STR "MB/s"
  #define SPEED_G_STR "GB/s"
  #define SPEED_T_STR "TB/s"
  
  #define LOGFILE_MODE_STR "a+"
  
  static bool paused = false;
  static bool closing = false;
  static bool seenHUP = false;
  static const char *logfileName = NULL;
  static FILE *logfile = NULL;
  static tr_session * mySession = NULL;
  
  /***
  ****  Config File
  ***/
  
  static const char *
  getUsage (void)
  {
      return "Transmission " LONG_VERSION_STRING
             "  http://www.transmissionbt.com/\n"
             "A fast and easy BitTorrent client\n"
             "\n"
             MY_NAME " is a headless Transmission session\n"
             "that can be controlled via transmission-remote\n"
             "or the web interface.\n"
             "\n"
             "Usage: " MY_NAME " [options]";
  }
  
  static const struct tr_option options[] =
  {
  
      { 'a', "allowed", "Allowed IP addresses. (Default: " TR_DEFAULT_RPC_WHITELIST ")", "a", 1, "<list>" },
      { 'b', "blocklist", "Enable peer blocklists", "b", 0, NULL },
      { 'B', "no-blocklist", "Disable peer blocklists", "B", 0, NULL },
      { 'c', "watch-dir", "Where to watch for new .torrent files", "c", 1, "<directory>" },
      { 'C', "no-watch-dir", "Disable the watch-dir", "C", 0, NULL },
      { 941, "incomplete-dir", "Where to store new torrents until they're complete", NULL, 1, "<directory>" },
      { 942, "no-incomplete-dir", "Don't store incomplete torrents in a different location", NULL, 0, NULL },
      { 'd', "dump-settings", "Dump the settings and exit", "d", 0, NULL },
      { 'e', "logfile", "Dump the log messages to this filename", "e", 1, "<filename>" },
      { 'f', "foreground", "Run in the foreground instead of daemonizing", "f", 0, NULL },
      { 'g', "config-dir", "Where to look for configuration files", "g", 1, "<path>" },
      { 'p', "port", "RPC port (Default: " TR_DEFAULT_RPC_PORT_STR ")", "p", 1, "<port>" },
      { 't', "auth", "Require authentication", "t", 0, NULL },
      { 'T', "no-auth", "Don't require authentication", "T", 0, NULL },
      { 'u', "username", "Set username for authentication", "u", 1, "<username>" },
      { 'v', "password", "Set password for authentication", "v", 1, "<password>" },
      { 'V', "version", "Show version number and exit", "V", 0, NULL },
      { 810, "log-error", "Show error messages", NULL, 0, NULL },
      { 811, "log-info", "Show error and info messages", NULL, 0, NULL },
      { 812, "log-debug", "Show error, info, and debug messages", NULL, 0, NULL },
      { 'w', "download-dir", "Where to save downloaded data", "w", 1, "<path>" },
      { 800, "paused", "Pause all torrents on startup", NULL, 0, NULL },
      { 'o', "dht", "Enable distributed hash tables (DHT)", "o", 0, NULL },
      { 'O', "no-dht", "Disable distributed hash tables (DHT)", "O", 0, NULL },
      { 'y', "lpd", "Enable local peer discovery (LPD)", "y", 0, NULL },
      { 'Y', "no-lpd", "Disable local peer discovery (LPD)", "Y", 0, NULL },
      { 830, "utp", "Enable uTP for peer connections", NULL, 0, NULL },
      { 831, "no-utp", "Disable uTP for peer connections", NULL, 0, NULL },
      { 'P', "peerport", "Port for incoming peers (Default: " TR_DEFAULT_PEER_PORT_STR ")", "P", 1, "<port>" },
      { 'm', "portmap", "Enable portmapping via NAT-PMP or UPnP", "m", 0, NULL },
      { 'M', "no-portmap", "Disable portmapping", "M", 0, NULL },
      { 'L', "peerlimit-global", "Maximum overall number of peers (Default: " TR_DEFAULT_PEER_LIMIT_GLOBAL_STR ")", "L", 1, "<limit>" },
      { 'l', "peerlimit-torrent", "Maximum number of peers per torrent (Default: " TR_DEFAULT_PEER_LIMIT_TORRENT_STR ")", "l", 1, "<limit>" },
      { 910, "encryption-required",  "Encrypt all peer connections", "er", 0, NULL },
      { 911, "encryption-preferred", "Prefer encrypted peer connections", "ep", 0, NULL },
      { 912, "encryption-tolerated", "Prefer unencrypted peer connections", "et", 0, NULL },
      { 'i', "bind-address-ipv4", "Where to listen for peer connections", "i", 1, "<ipv4 addr>" },
      { 'I', "bind-address-ipv6", "Where to listen for peer connections", "I", 1, "<ipv6 addr>" },
      { 'r', "rpc-bind-address", "Where to listen for RPC connections", "r", 1, "<ipv4 addr>" },
      { 953, "global-seedratio", "All torrents, unless overridden by a per-torrent setting, should seed until a specific ratio", "gsr", 1, "ratio" },
      { 954, "no-global-seedratio", "All torrents, unless overridden by a per-torrent setting, should seed regardless of ratio", "GSR", 0, NULL },
      { 'x', "pid-file", "Enable PID file", "x", 1, "<pid-file>" },
      { 0, NULL, NULL, NULL, 0, NULL }
  };
  
  static void
  showUsage (void)
  {
      tr_getopt_usage (MY_NAME, getUsage (), options);
      exit (0);
  }
  
  static void
  gotsig (int sig)
  {
      switch (sig)
      {
          case SIGHUP:
          {
              if (!mySession)
              {
                  tr_inf ("Deferring reload until session is fully started.");
                  seenHUP = true;
              }
              else
              {
                  tr_benc settings;
                  const char * configDir;
  
                  /* reopen the logfile to allow for log rotation */
                  if (logfileName) {
                      logfile = freopen (logfileName, LOGFILE_MODE_STR, logfile);
                      if (!logfile)
                          fprintf (stderr, "Couldn't reopen \"%s\": %s\n", logfileName, tr_strerror (errno));
                  }
  
                  configDir = tr_sessionGetConfigDir (mySession);
                  tr_inf ("Reloading settings from \"%s\"", configDir);
                  tr_bencInitDict (&settings, 0);
                  tr_bencDictAddBool (&settings, TR_PREFS_KEY_RPC_ENABLED, true);
                  tr_sessionLoadSettings (&settings, configDir, MY_NAME);
                  tr_sessionSet (mySession, &settings);
                  tr_bencFree (&settings);
                  tr_sessionReloadBlocklists (mySession);
              }
              break;
          }
  
          default:
              tr_err ("Unexpected signal (%d) in daemon, closing.", sig);
              /* no break */
  
          case SIGINT:
          case SIGTERM:
              closing = true;
              break;
      }
  }
  
  #if defined (WIN32)
   #define USE_NO_DAEMON
  #elif !defined (HAVE_DAEMON) || defined (__UCLIBC__)
   #define USE_TR_DAEMON
  #else
   #define USE_OS_DAEMON
  #endif
  
  static int
  tr_daemon (int nochdir, int noclose)
  {
  #if defined (USE_OS_DAEMON)
  
      return daemon (nochdir, noclose);
  
  #elif defined (USE_TR_DAEMON)
  
      /* this is loosely based off of glibc's daemon () implementation
       * http://sourceware.org/git/?p=glibc.git;a=blob_plain;f=misc/daemon.c */
  
      switch (fork ()) {
          case -1: return -1;
          case 0: break;
          default: _exit (0);
      }
  
      if (setsid () == -1)
          return -1;
  
      if (!nochdir)
          chdir ("/");
  
      if (!noclose) {
          int fd = open ("/dev/null", O_RDWR, 0);
          dup2 (fd, STDIN_FILENO);
          dup2 (fd, STDOUT_FILENO);
          dup2 (fd, STDERR_FILENO);
          close (fd);
      }
  
      return 0;
  
  #else /* USE_NO_DAEMON */
      return 0;
  #endif
  }
  
  static const char*
  getConfigDir (int argc, const char ** argv)
  {
      int c;
      const char * configDir = NULL;
      const char * optarg;
      const int ind = tr_optind;
  
      while ((c = tr_getopt (getUsage (), argc, argv, options, &optarg))) {
          if (c == 'g') {
              configDir = optarg;
              break;
          }
      }
  
      tr_optind = ind;
  
      if (configDir == NULL)
          configDir = tr_getDefaultConfigDir (MY_NAME);
  
      return configDir;
  }
  
  static void
  onFileAdded (tr_session * session, const char * dir, const char * file)
  {
      char * filename = tr_buildPath (dir, file, NULL);
      tr_ctor * ctor = tr_ctorNew (session);
      int err = tr_ctorSetMetainfoFromFile (ctor, filename);
  
      if (!err)
      {
          tr_torrentNew (ctor, &err);
  
          if (err == TR_PARSE_ERR)
              tr_err ("Error parsing .torrent file \"%s\"", file);
          else
          {
              bool trash = false;
              int test = tr_ctorGetDeleteSource (ctor, &trash);
  
              tr_inf ("Parsing .torrent file successful \"%s\"", file);
  
              if (!test && trash)
              {
                  tr_inf ("Deleting input .torrent file \"%s\"", file);
                  if (remove (filename))
                      tr_err ("Error deleting .torrent file: %s", tr_strerror (errno));
              }
              else
              {
                  char * new_filename = tr_strdup_printf ("%s.added", filename);
                  rename (filename, new_filename);
                  tr_free (new_filename);
              }
          }
      }
  
      tr_ctorFree (ctor);
      tr_free (filename);
  }
  
  static void
  printMessage (FILE * logfile, int level, const char * name, const char * message, const char * file, int line)
  {
      if (logfile != NULL)
      {
          char timestr[64];
          tr_getLogTimeStr (timestr, sizeof (timestr));
          if (name)
              fprintf (logfile, "[%s] %s %s (%s:%d)\n", timestr, name, message, file, line);
          else
              fprintf (logfile, "[%s] %s (%s:%d)\n", timestr, message, file, line);
      }
  #ifdef HAVE_SYSLOG
      else /* daemon... write to syslog */
      {
          int priority;
  
          /* figure out the syslog priority */
          switch (level) {
              case TR_MSG_ERR: priority = LOG_ERR; break;
              case TR_MSG_DBG: priority = LOG_DEBUG; break;
              default: priority = LOG_INFO; break;
          }
  
          if (name)
              syslog (priority, "%s %s (%s:%d)", name, message, file, line);
          else
              syslog (priority, "%s (%s:%d)", message, file, line);
      }
  #endif
  }
  
  static void
  pumpLogMessages (FILE * logfile)
  {
      const tr_msg_list * l;
      tr_msg_list * list = tr_getQueuedMessages ();
  
      for (l=list; l!=NULL; l=l->next)
          printMessage (logfile, l->level, l->name, l->message, l->file, l->line);
  
      if (logfile != NULL)
          fflush (logfile);
  
      tr_freeMessageList (list);
  }
  
  static tr_rpc_callback_status
  on_rpc_callback (tr_session            * session UNUSED,
                   tr_rpc_callback_type    type,
                   struct tr_torrent     * tor UNUSED,
                   void                  * user_data UNUSED)
  {
      if (type == TR_RPC_SESSION_CLOSE)
          closing = true;
      return TR_RPC_OK;
  }
  
  int
  main (int argc, char ** argv)
  {
      int c;
      const char * optarg;
      tr_benc settings;
      bool boolVal;
      bool loaded;
      bool foreground = false;
      bool dumpSettings = false;
      const char * configDir = NULL;
      const char * pid_filename;
      dtr_watchdir * watchdir = NULL;
      bool pidfile_created = false;
      tr_session * session = NULL;
  
      signal (SIGINT, gotsig);
      signal (SIGTERM, gotsig);
  #ifndef WIN32
      signal (SIGHUP, gotsig);
  #endif
  
      /* load settings from defaults + config file */
      tr_bencInitDict (&settings, 0);
      tr_bencDictAddBool (&settings, TR_PREFS_KEY_RPC_ENABLED, true);
      configDir = getConfigDir (argc, (const char**)argv);
      loaded = tr_sessionLoadSettings (&settings, configDir, MY_NAME);
  
      /* overwrite settings from the comamndline */
      tr_optind = 1;
      while ((c = tr_getopt (getUsage (), argc, (const char**)argv, options, &optarg))) {
          switch (c) {
              case 'a': tr_bencDictAddStr (&settings, TR_PREFS_KEY_RPC_WHITELIST, optarg);
                        tr_bencDictAddBool (&settings, TR_PREFS_KEY_RPC_WHITELIST_ENABLED, true);
                        break;
              case 'b': tr_bencDictAddBool (&settings, TR_PREFS_KEY_BLOCKLIST_ENABLED, true);
                        break;
              case 'B': tr_bencDictAddBool (&settings, TR_PREFS_KEY_BLOCKLIST_ENABLED, false);
                        break;
              case 'c': tr_bencDictAddStr (&settings, PREF_KEY_DIR_WATCH, optarg);
                        tr_bencDictAddBool (&settings, PREF_KEY_DIR_WATCH_ENABLED, true);
                        break;
              case 'C': tr_bencDictAddBool (&settings, PREF_KEY_DIR_WATCH_ENABLED, false);
                        break;
              case 941: tr_bencDictAddStr (&settings, TR_PREFS_KEY_INCOMPLETE_DIR, optarg);
                        tr_bencDictAddBool (&settings, TR_PREFS_KEY_INCOMPLETE_DIR_ENABLED, true);
                        break;
              case 942: tr_bencDictAddBool (&settings, TR_PREFS_KEY_INCOMPLETE_DIR_ENABLED, false);
                        break;
              case 'd': dumpSettings = true;
                        break;
              case 'e': logfile = fopen (optarg, LOGFILE_MODE_STR);
                        if (logfile)
                            logfileName = optarg;
                        else
                            fprintf (stderr, "Couldn't open \"%s\": %s\n", optarg, tr_strerror (errno));
                        break;
              case 'f': foreground = true;
                        break;
              case 'g': /* handled above */
                        break;
              case 'V': /* version */
                        fprintf (stderr, "%s %s\n", MY_NAME, LONG_VERSION_STRING);
                        exit (0);
              case 'o': tr_bencDictAddBool (&settings, TR_PREFS_KEY_DHT_ENABLED, true);
                        break;
              case 'O': tr_bencDictAddBool (&settings, TR_PREFS_KEY_DHT_ENABLED, false);
                        break;
              case 'p': tr_bencDictAddInt (&settings, TR_PREFS_KEY_RPC_PORT, atoi (optarg));
                        break;
              case 't': tr_bencDictAddBool (&settings, TR_PREFS_KEY_RPC_AUTH_REQUIRED, true);
                        break;
              case 'T': tr_bencDictAddBool (&settings, TR_PREFS_KEY_RPC_AUTH_REQUIRED, false);
                        break;
              case 'u': tr_bencDictAddStr (&settings, TR_PREFS_KEY_RPC_USERNAME, optarg);
                        break;
              case 'v': tr_bencDictAddStr (&settings, TR_PREFS_KEY_RPC_PASSWORD, optarg);
                        break;
              case 'w': tr_bencDictAddStr (&settings, TR_PREFS_KEY_DOWNLOAD_DIR, optarg);
                        break;
              case 'P': tr_bencDictAddInt (&settings, TR_PREFS_KEY_PEER_PORT, atoi (optarg));
                        break;
              case 'm': tr_bencDictAddBool (&settings, TR_PREFS_KEY_PORT_FORWARDING, true);
                        break;
              case 'M': tr_bencDictAddBool (&settings, TR_PREFS_KEY_PORT_FORWARDING, false);
                        break;
              case 'L': tr_bencDictAddInt (&settings, TR_PREFS_KEY_PEER_LIMIT_GLOBAL, atoi (optarg));
                        break;
              case 'l': tr_bencDictAddInt (&settings, TR_PREFS_KEY_PEER_LIMIT_TORRENT, atoi (optarg));
                        break;
              case 800: paused = true;
                        break;
              case 910: tr_bencDictAddInt (&settings, TR_PREFS_KEY_ENCRYPTION, TR_ENCRYPTION_REQUIRED);
                        break;
              case 911: tr_bencDictAddInt (&settings, TR_PREFS_KEY_ENCRYPTION, TR_ENCRYPTION_PREFERRED);
                        break;
              case 912: tr_bencDictAddInt (&settings, TR_PREFS_KEY_ENCRYPTION, TR_CLEAR_PREFERRED);
                        break;
              case 'i': tr_bencDictAddStr (&settings, TR_PREFS_KEY_BIND_ADDRESS_IPV4, optarg);
                        break;
              case 'I': tr_bencDictAddStr (&settings, TR_PREFS_KEY_BIND_ADDRESS_IPV6, optarg);
                        break;
              case 'r': tr_bencDictAddStr (&settings, TR_PREFS_KEY_RPC_BIND_ADDRESS, optarg);
                        break;
              case 953: tr_bencDictAddReal (&settings, TR_PREFS_KEY_RATIO, atof (optarg));
                        tr_bencDictAddBool (&settings, TR_PREFS_KEY_RATIO_ENABLED, true);
                        break;
              case 954: tr_bencDictAddBool (&settings, TR_PREFS_KEY_RATIO_ENABLED, false);
                        break;
              case 'x': tr_bencDictAddStr (&settings, PREF_KEY_PIDFILE, optarg);
                        break;
              case 'y': tr_bencDictAddBool (&settings, TR_PREFS_KEY_LPD_ENABLED, true);
                        break;
              case 'Y': tr_bencDictAddBool (&settings, TR_PREFS_KEY_LPD_ENABLED, false);
                        break;
              case 810: tr_bencDictAddInt (&settings,  TR_PREFS_KEY_MSGLEVEL, TR_MSG_ERR);
                        break;
              case 811: tr_bencDictAddInt (&settings,  TR_PREFS_KEY_MSGLEVEL, TR_MSG_INF);
                        break;
              case 812: tr_bencDictAddInt (&settings,  TR_PREFS_KEY_MSGLEVEL, TR_MSG_DBG);
                        break;
              case 830: tr_bencDictAddBool (&settings, TR_PREFS_KEY_UTP_ENABLED, true);
                        break;
              case 831: tr_bencDictAddBool (&settings, TR_PREFS_KEY_UTP_ENABLED, false);
                        break;
              default:  showUsage ();
                        break;
          }
      }
  
      if (foreground && !logfile)
          logfile = stderr;
  
      if (!loaded)
      {
          printMessage (logfile, TR_MSG_ERR, MY_NAME, "Error loading config file -- exiting.", __FILE__, __LINE__);
          return -1;
      }
  
      if (dumpSettings)
      {
          char * str = tr_bencToStr (&settings, TR_FMT_JSON, NULL);
          fprintf (stderr, "%s", str);
          tr_free (str);
          return 0;
      }
  
      if (!foreground && tr_daemon (true, false) < 0)
      {
          char buf[256];
          tr_snprintf (buf, sizeof (buf), "Failed to daemonize: %s", tr_strerror (errno));
          printMessage (logfile, TR_MSG_ERR, MY_NAME, buf, __FILE__, __LINE__);
          exit (1);
      }
  
      /* start the session */
      tr_formatter_mem_init (MEM_K, MEM_K_STR, MEM_M_STR, MEM_G_STR, MEM_T_STR);
      tr_formatter_size_init (DISK_K, DISK_K_STR, DISK_M_STR, DISK_G_STR, DISK_T_STR);
      tr_formatter_speed_init (SPEED_K, SPEED_K_STR, SPEED_M_STR, SPEED_G_STR, SPEED_T_STR);
      session = tr_sessionInit ("daemon", configDir, true, &settings);
      tr_sessionSetRPCCallback (session, on_rpc_callback, NULL);
      tr_ninf (NULL, "Using settings from \"%s\"", configDir);
      tr_sessionSaveSettings (session, configDir, &settings);
  
      pid_filename = NULL;
      tr_bencDictFindStr (&settings, PREF_KEY_PIDFILE, &pid_filename);
      if (pid_filename && *pid_filename)
      {
          FILE * fp = fopen (pid_filename, "w+");
          if (fp != NULL)
          {
              fprintf (fp, "%d", (int)getpid ());
              fclose (fp);
              tr_inf ("Saved pidfile \"%s\"", pid_filename);
              pidfile_created = true;
          }
          else
              tr_err ("Unable to save pidfile \"%s\": %s", pid_filename, tr_strerror (errno));
      }
  
      if (tr_bencDictFindBool (&settings, TR_PREFS_KEY_RPC_AUTH_REQUIRED, &boolVal) && boolVal)
          tr_ninf (MY_NAME, "requiring authentication");
  
      mySession = session;
  
      /* If we got a SIGHUP during startup, process that now. */
      if (seenHUP)
          gotsig (SIGHUP);
  
      /* maybe add a watchdir */
      {
          const char * dir;
  
          if (tr_bencDictFindBool (&settings, PREF_KEY_DIR_WATCH_ENABLED, &boolVal)
              && boolVal
              && tr_bencDictFindStr (&settings, PREF_KEY_DIR_WATCH, &dir)
              && dir
              && *dir)
          {
              tr_inf ("Watching \"%s\" for new .torrent files", dir);
              watchdir = dtr_watchdir_new (mySession, dir, onFileAdded);
          }
      }
  
      /* load the torrents */
      {
          tr_torrent ** torrents;
          tr_ctor * ctor = tr_ctorNew (mySession);
          if (paused)
              tr_ctorSetPaused (ctor, TR_FORCE, true);
          torrents = tr_sessionLoadTorrents (mySession, ctor, NULL);
          tr_free (torrents);
          tr_ctorFree (ctor);
      }
  
  #ifdef HAVE_SYSLOG
      if (!foreground)
          openlog (MY_NAME, LOG_CONS|LOG_PID, LOG_DAEMON);
  #endif
  
      while (!closing) {
          tr_wait_msec (1000); /* sleep one second */
          dtr_watchdir_update (watchdir);
          pumpLogMessages (logfile);
      }
  
      printf ("Closing transmission session...");
      tr_sessionSaveSettings (mySession, configDir, &settings);
      dtr_watchdir_free (watchdir);
      tr_sessionClose (mySession);
      pumpLogMessages (logfile);
      printf (" done.\n");
  
      /* shutdown */
  #if HAVE_SYSLOG
      if (!foreground)
      {
          syslog (LOG_INFO, "%s", "Closing session");
          closelog ();
      }
  #endif
  
      /* cleanup */
      if (pidfile_created)
          remove (pid_filename);
      tr_bencFree (&settings);
      return 0;
  }
  