src/PVE/Daemon.pm

   1 package PVE::Daemon;
   2
   3 # Abstract class to implement Daemons
   4 #
   5 # Features:
   6 # * lock and write PID file /var/run/$name.pid to make sure onyl
   7 #   one instance is running.
   8 # * keep lock open during restart
   9 # * correctly daemonize (redirect STDIN/STDOUT)
  10 # * restart by stop/start, exec, or signal HUP
  11 # * daemon restart on error (option 'restart_on_error')
  12 # * handle worker processes (option 'max_workers')
  13 # * allow to restart while workers are still runningl
  14 #   (option 'leave_children_open_on_reload')
  15 # * run as different user using setuid/setgid
  16
  17 use strict;
  18 use warnings;
  19 use English;
  20
  21 use PVE::SafeSyslog;
  22 use PVE::INotify;
  23
  24 use POSIX ":sys_wait_h";
  25 use Fcntl ':flock';
  26 use Socket qw(IPPROTO_TCP TCP_NODELAY SOMAXCONN);
  27 use IO::Socket::IP;
  28
  29 use Getopt::Long;
  30 use Time::HiRes qw (gettimeofday);
  31
  32 use base qw(PVE::CLIHandler);
  33
  34 $ENV{'PATH'} = '/sbin:/bin:/usr/sbin:/usr/bin';
  35
  36 my $daemon_initialized = 0; # we only allow one instance
  37
  38 my $close_daemon_lock = sub {
  39     my ($self) = @_;
  40
  41     return if !$self->{daemon_lock_fh};
  42
  43     close $self->{daemon_lock_fh};
  44     delete $self->{daemon_lock_fh};
  45 };
  46
  47 my $log_err = sub {
  48     my ($msg) = @_;
  49     chomp $msg;
  50     print STDERR "$msg\n";
  51     syslog('err', "%s", $msg);
  52 };
  53
  54 # call this if you fork() from child
  55 # Note: we already call this for workers, so it is only required
  56 # if you fork inside a simple daemon (max_workers == 0).
  57 sub after_fork_cleanup {
  58     my ($self) = @_;
  59
  60     &$close_daemon_lock($self);
  61
  62     PVE::INotify::inotify_close();
  63
  64     for my $sig (qw(CHLD HUP INT TERM QUIT)) {
  65         $SIG{$sig} = 'DEFAULT'; # restore default handler
  66         # AnyEvent signals only works if $SIG{XX} is
  67         # undefined (perl event loop)
  68         delete $SIG{$sig}; # so that we can handle events with AnyEvent
  69     }
  70 }
  71
  72 my $lockpidfile = sub {
  73     my ($self) = @_;
  74
  75     my $lkfn = $self->{pidfile} . ".lock";
  76
  77     my $waittime = 0;
  78
  79     if (my $fd = $self->{env_pve_lock_fd}) {
  80
  81         $self->{daemon_lock_fh} = IO::Handle->new_from_fd($fd, "a");
  82
  83     } else {
  84
  85         $waittime = 5;
  86         $self->{daemon_lock_fh} = IO::File->new(">>$lkfn");
  87     }
  88
  89     if (!$self->{daemon_lock_fh}) {
  90         die "can't open lock '$lkfn' - $!\n";
  91     }
  92
  93     for (my $i = 0; $i < $waittime; $i ++) {
  94         return if flock ($self->{daemon_lock_fh}, LOCK_EX|LOCK_NB);
  95         sleep(1);
  96     }
  97
  98     if (!flock ($self->{daemon_lock_fh}, LOCK_EX|LOCK_NB)) {
  99         &$close_daemon_lock($self);
 100         my $err = $!;
 101
 102         my ($running, $pid) = $self->running();
 103         if ($running) {
 104             die "can't aquire lock '$lkfn' - daemon already started (pid = $pid)\n";
 105         } else {
 106             die "can't aquire lock '$lkfn' - $err\n";
 107         }
 108     }
 109 };
 110
 111 my $writepidfile = sub {
 112     my ($self) = @_;
 113
 114     my $pidfile = $self->{pidfile};
 115
 116     die "can't open pid file '$pidfile' - $!\n" if !open (PIDFH, ">$pidfile");
 117
 118     print PIDFH "$$\n";
 119     close (PIDFH);
 120 };
 121
 122 my $server_cleanup = sub {
 123     my ($self) = @_;
 124
 125     unlink $self->{pidfile} . ".lock";
 126     unlink $self->{pidfile};
 127 };
 128
 129 my $finish_workers = sub {
 130     my ($self) = @_;
 131
 132     foreach my $id (qw(workers old_workers)) {
 133         foreach my $cpid (keys %{$self->{$id}}) {
 134             my $waitpid = waitpid($cpid, WNOHANG);
 135             if (defined($waitpid) && ($waitpid == $cpid)) {
 136                 delete ($self->{$id}->{$cpid});
 137                 syslog('info', "worker $cpid finished");
 138             }
 139         }
 140     }
 141 };
 142
 143 my $start_workers = sub {
 144     my ($self) = @_;
 145
 146     return if $self->{terminate};
 147
 148     my $count = 0;
 149     foreach my $cpid (keys %{$self->{workers}}) {
 150         $count++;
 151     }
 152
 153     my $need = $self->{max_workers} - $count;
 154
 155     return if $need <= 0;
 156
 157     syslog('info', "starting $need worker(s)");
 158
 159     while ($need > 0) {
 160         my $pid = fork;
 161
 162         if (!defined ($pid)) {
 163             syslog('err', "can't fork worker");
 164             sleep (1);
 165         } elsif ($pid) { # parent
 166             $self->{workers}->{$pid} = 1;
 167             syslog('info', "worker $pid started");
 168             $need--;
 169         } else {
 170             $0 = "$self->{name} worker";
 171
 172             $self->after_fork_cleanup();
 173
 174             eval { $self->run(); };
 175             if (my $err = $@) {
 176                 syslog('err', $err);
 177                 sleep(5); # avoid fast restarts
 178             }
 179
 180             syslog('info', "worker exit");
 181             exit (0);
 182         }
 183     }
 184 };
 185
 186 my $terminate_server = sub {
 187     my ($self, $allow_open_children) = @_;
 188
 189     $self->{terminate} = 1; # set flag to avoid worker restart
 190
 191     if (!$self->{max_workers}) {
 192         eval { $self->shutdown(); };
 193         warn $@ if $@;
 194         return;
 195     }
 196
 197     eval { $self->shutdown(); };
 198     warn $@ if $@;
 199
 200     # we have workers - send TERM signal
 201
 202     foreach my $cpid (keys %{$self->{workers}}) {
 203         kill(15, $cpid); # TERM childs
 204     }
 205
 206     # if configured, leave children running on HUP
 207     return if $allow_open_children &&
 208         $self->{leave_children_open_on_reload};
 209
 210     # else, send TERM to old workers
 211     foreach my $cpid (keys %{$self->{old_workers}}) {
 212         kill(15, $cpid); # TERM childs
 213     }
 214
 215     # nicely shutdown childs (give them max 10 seconds to shut down)
 216     my $previous_alarm = alarm(10);
 217     eval {
 218         local $SIG{ALRM} = sub { die "timeout\n" };
 219
 220         while ((my $pid = waitpid (-1, 0)) > 0) {
 221             foreach my $id (qw(workers old_workers)) {
 222                 if (defined($self->{$id}->{$pid})) {
 223                     delete($self->{$id}->{$pid});
 224                     syslog('info', "worker $pid finished");
 225                 }
 226             }
 227         }
 228         alarm(0); # avoid race condition
 229     };
 230     my $err = $@;
 231
 232     alarm ($previous_alarm);
 233
 234     if ($err) {
 235         syslog('err', "error stopping workers (will kill them now) - $err");
 236         foreach my $id (qw(workers old_workers)) {
 237             foreach my $cpid (keys %{$self->{$id}}) {
 238                 # KILL childs still alive!
 239                 if (kill (0, $cpid)) {
 240                     delete($self->{$id}->{$cpid});
 241                     syslog("err", "kill worker $cpid");
 242                     kill(9, $cpid);
 243                     # fixme: waitpid?
 244                 }
 245             }
 246         }
 247     }
 248 };
 249
 250 sub setup {
 251     my ($self) = @_;
 252
 253     initlog($self->{name});
 254
 255     my $restart = $ENV{RESTART_PVE_DAEMON};
 256     delete $ENV{RESTART_PVE_DAEMON};
 257     $self->{env_restart_pve_daemon} = $restart;
 258
 259     my $lockfd = $ENV{PVE_DAEMON_LOCK_FD};
 260     delete $ENV{PVE_DAEMON_LOCK_FD};
 261     if (defined($lockfd)) {
 262         die "unable to parse lock fd '$lockfd'\n"
 263             if $lockfd !~ m/^(\d+)$/;
 264         $lockfd = $1; # untaint
 265     }
 266     $self->{env_pve_lock_fd} = $lockfd;
 267
 268     die "please run as root\n" if !$restart && ($> != 0);
 269
 270     die "can't create more that one PVE::Daemon" if $daemon_initialized;
 271     $daemon_initialized = 1;
 272
 273     PVE::INotify::inotify_init();
 274
 275     if (my $gidstr = $self->{setgid}) {
 276         my $gid = getgrnam($gidstr) || die "getgrnam failed - $!\n";
 277         POSIX::setgid($gid) || die "setgid $gid failed - $!\n";
 278         $EGID = "$gid $gid"; # this calls setgroups
 279         # just to be sure
 280         die "detected strange gid\n" if !($GID eq "$gid $gid" && $EGID eq "$gid $gid");
 281     }
 282
 283     if (my $uidstr = $self->{setuid}) {
 284         my $uid = getpwnam($uidstr) || die "getpwnam failed - $!\n";
 285         POSIX::setuid($uid) || die "setuid $uid failed - $!\n";
 286         # just to be sure
 287         die "detected strange uid\n" if !($UID == $uid && $EUID == $uid);
 288     }
 289
 290     if ($restart && $self->{max_workers}) {
 291         if (my $wpids = $ENV{PVE_DAEMON_WORKER_PIDS}) {
 292             foreach my $pid (split(':', $wpids)) {
 293                 if ($pid =~ m/^(\d+)$/) {
 294                     $self->{old_workers}->{$1} = 1;
 295                 }
 296             }
 297         }
 298     }
 299
 300     $self->{nodename} = PVE::INotify::nodename();
 301 }
 302
 303 my $server_run = sub {
 304     my ($self, $debug) = @_;
 305
 306     # fixme: handle restart lockfd
 307     &$lockpidfile($self);
 308
 309     # remove FD_CLOEXEC bit to reuse on exec
 310     $self->{daemon_lock_fh}->fcntl(Fcntl::F_SETFD(), 0);
 311
 312     $ENV{PVE_DAEMON_LOCK_FD} = $self->{daemon_lock_fh}->fileno;
 313
 314     # run in background
 315     my $spid;
 316
 317     $self->{debug} = 1 if $debug;
 318
 319     $self->init();
 320
 321     if (!$debug) {
 322         open STDIN,  '</dev/null' || die "can't read /dev/null";
 323         open STDOUT, '>/dev/null' || die "can't write /dev/null";
 324     }
 325
 326     if (!$self->{env_restart_pve_daemon} && !$debug) {
 327         PVE::INotify::inotify_close();
 328         $spid = fork();
 329         if (!defined ($spid)) {
 330             die "can't put server into background - fork failed";
 331         } elsif ($spid) { # parent
 332             exit (0);
 333         }
 334         PVE::INotify::inotify_init();
 335     }
 336
 337     if ($self->{env_restart_pve_daemon}) {
 338         syslog('info' , "restarting server");
 339     } else {
 340         &$writepidfile($self);
 341         syslog('info' , "starting server");
 342     }
 343
 344     POSIX::setsid();
 345
 346     open STDERR, '>&STDOUT' || die "can't close STDERR\n";
 347
 348     my $old_sig_term = $SIG{TERM};
 349     local $SIG{TERM} = sub {
 350         local ($@, $!, $?); # do not overwrite error vars
 351         syslog('info', "received signal TERM");
 352         &$terminate_server($self, 0);
 353         &$server_cleanup($self);
 354         &$old_sig_term(@_) if $old_sig_term;
 355     };
 356
 357     my $old_sig_quit = $SIG{QUIT};
 358     local $SIG{QUIT} = sub {
 359         local ($@, $!, $?); # do not overwrite error vars
 360         syslog('info', "received signal QUIT");
 361         &$terminate_server($self, 0);
 362         &$server_cleanup($self);
 363         &$old_sig_quit(@_) if $old_sig_quit;
 364     };
 365
 366     my $old_sig_int = $SIG{INT};
 367     local $SIG{INT} = sub {
 368         local ($@, $!, $?); # do not overwrite error vars
 369         syslog('info', "received signal INT");
 370         $SIG{INT} = 'DEFAULT'; # allow to terminate now
 371         &$terminate_server($self, 0);
 372         &$server_cleanup($self);
 373         &$old_sig_int(@_) if $old_sig_int;
 374     };
 375
 376     $SIG{HUP} = sub {
 377         local ($@, $!, $?); # do not overwrite error vars
 378         syslog('info', "received signal HUP");
 379         $self->{got_hup_signal} = 1;
 380         if ($self->{max_workers}) {
 381             &$terminate_server($self, 1);
 382         } elsif ($self->can('hup')) {
 383             eval { $self->hup() };
 384             warn $@ if $@;
 385         }
 386     };
 387
 388     eval {
 389         if ($self->{max_workers}) {
 390             my $old_sig_chld = $SIG{CHLD};
 391             local $SIG{CHLD} = sub {
 392                 local ($@, $!, $?); # do not overwrite error vars
 393                 &$finish_workers($self);
 394                 &$old_sig_chld(@_) if $old_sig_chld;
 395             };
 396
 397             # catch worker finished during restart phase
 398             &$finish_workers($self);
 399
 400             # now loop forever (until we receive terminate signal)
 401             for (;;) {
 402                 &$start_workers($self);
 403                 sleep(5);
 404                 &$finish_workers($self);
 405                 last if $self->{terminate};
 406             }
 407
 408         } else {
 409             $self->run();
 410         }
 411     };
 412     my $err = $@;
 413
 414     if ($err) {
 415         syslog ('err', "ERROR: $err");
 416
 417         &$terminate_server($self, 1);
 418
 419         if (my $wait_time = $self->{restart_on_error}) {
 420             $self->restart_daemon($wait_time);
 421         } else {
 422             $self->exit_daemon(-1);
 423         }
 424     }
 425
 426     if ($self->{got_hup_signal}) {
 427         $self->restart_daemon();
 428     } else {
 429         $self->exit_daemon(0);
 430     }
 431 };
 432
 433 sub new {
 434     my ($this, $name, $cmdline, %params) = @_;
 435
 436     $name = 'daemon' if !$name; # should not happen
 437
 438     my $self;
 439
 440     eval {
 441         my $class = ref($this) || $this;
 442
 443         $self = bless {
 444             name => $name,
 445             pidfile => "/var/run/${name}.pid",
 446             workers => {},
 447             old_workers => {},
 448         }, $class;
 449
 450
 451         foreach my $opt (keys %params) {
 452             my $value = $params{$opt};
 453             if ($opt eq 'restart_on_error') {
 454                 $self->{$opt} = $value;
 455             } elsif ($opt eq 'stop_wait_time') {
 456                 $self->{$opt} = $value;
 457             } elsif ($opt eq 'pidfile') {
 458                 $self->{$opt} = $value;
 459             } elsif ($opt eq 'max_workers') {
 460                 $self->{$opt} = $value;
 461             } elsif ($opt eq 'leave_children_open_on_reload') {
 462                 $self->{$opt} = $value;
 463             } elsif ($opt eq 'setgid') {
 464                 $self->{$opt} = $value;
 465             } elsif ($opt eq 'setuid') {
 466                 $self->{$opt} = $value;
 467             } else {
 468                 die "unknown daemon option '$opt'\n";
 469             }
 470         }
 471
 472
 473         # untaint
 474         $self->{cmdline} = [map { /^(.*)$/ } @$cmdline];
 475
 476         $0 = $name;
 477     };
 478     if (my $err = $@) {
 479         &$log_err($err);
 480         exit(-1);
 481     }
 482
 483     return $self;
 484 }
 485
 486 sub exit_daemon {
 487     my ($self, $status) = @_;
 488
 489     syslog("info", "server stopped");
 490
 491     &$server_cleanup($self);
 492
 493     exit($status);
 494 }
 495
 496 sub restart_daemon {
 497     my ($self, $waittime) = @_;
 498
 499     syslog('info', "server shutdown (restart)");
 500
 501     $ENV{RESTART_PVE_DAEMON} = 1;
 502
 503     if ($self->{max_workers}) {
 504         my @workers = keys %{$self->{workers}};
 505         push @workers, keys %{$self->{old_workers}};
 506         $ENV{PVE_DAEMON_WORKER_PIDS} = join(':', @workers);
 507     }
 508
 509     sleep($waittime) if $waittime; # avoid high server load due to restarts
 510
 511     PVE::INotify::inotify_close();
 512
 513     exec (@{$self->{cmdline}});
 514
 515     exit (-1); # never reached?
 516 }
 517
 518 # please overwrite in subclass
 519 # this is called at startup - before forking
 520 sub init {
 521     my ($self) = @_;
 522
 523 }
 524
 525 # please overwrite in subclass
 526 sub shutdown {
 527     my ($self) = @_;
 528
 529     syslog('info' , "server closing");
 530
 531     if (!$self->{max_workers}) {
 532         # wait for children
 533         1 while (waitpid(-1, POSIX::WNOHANG()) > 0);
 534     }
 535 }
 536
 537 # please define in subclass
 538 #sub hup {
 539 #    my ($self) = @_;
 540 #
 541 #    syslog('info' , "received signal HUP (restart)");
 542 #}
 543
 544 # please overwrite in subclass
 545 sub run {
 546     my ($self) = @_;
 547
 548     for (;;) { # forever
 549         syslog('info' , "server is running");
 550         sleep(5);
 551     }
 552 }
 553
 554 sub start {
 555     my ($self, $debug) = @_;
 556
 557     eval  {
 558         $self->setup();
 559         &$server_run($self, $debug);
 560     };
 561     if (my $err = $@) {
 562         &$log_err("start failed - $err");
 563         exit(-1);
 564     }
 565 }
 566
 567 my $read_pid = sub {
 568     my ($self) = @_;
 569
 570     my $pid_str = PVE::Tools::file_read_firstline($self->{pidfile});
 571
 572     return 0 if !$pid_str;
 573
 574     return 0 if $pid_str !~ m/^(\d+)$/; # untaint
 575
 576     my $pid = int($1);
 577
 578     return $pid;
 579 };
 580
 581 # checks if the process was started by systemd
 582 my $init_ppid = sub {
 583
 584     if (getppid() == 1) {
 585        return 1;
 586     } else {
 587        return 0;
 588     }
 589 };
 590
 591 sub running {
 592     my ($self) = @_;
 593
 594     my $pid = &$read_pid($self);
 595
 596     if ($pid) {
 597         my $res = PVE::ProcFSTools::check_process_running($pid) ? 1 : 0;
 598         return wantarray ? ($res, $pid) : $res;
 599     }
 600
 601     return wantarray ? (0, 0) : 0;
 602 }
 603
 604 sub stop {
 605     my ($self) = @_;
 606
 607     my $pid = &$read_pid($self);
 608
 609     return if !$pid;
 610
 611     if (PVE::ProcFSTools::check_process_running($pid)) {
 612         kill(15, $pid); # send TERM signal
 613         # give some time
 614         my $wait_time = $self->{stop_wait_time} || 5;
 615         my $running = 1;
 616         for (my $i = 0; $i < $wait_time; $i++) {
 617             $running = PVE::ProcFSTools::check_process_running($pid);
 618             last if !$running;
 619             sleep (1);
 620         }
 621
 622         syslog('err', "server still running - send KILL") if $running;
 623
 624         # to be sure
 625         kill(9, $pid);
 626         waitpid($pid, 0);
 627     }
 628
 629     if (-f $self->{pidfile}) {
 630         eval {
 631             # try to get the lock
 632             &$lockpidfile($self);
 633             &$server_cleanup($self);
 634         };
 635         if (my $err = $@) {
 636             &$log_err("cleanup failed - $err");
 637         }
 638     }
 639 }
 640
 641 sub register_start_command {
 642     my ($self, $description) = @_;
 643
 644     my $class = ref($self);
 645
 646     $class->register_method({
 647         name => 'start',
 648         path => 'start',
 649         method => 'POST',
 650         description => $description || "Start the daemon.",
 651         parameters => {
 652             additionalProperties => 0,
 653             properties => {
 654                 debug => {
 655                     description => "Debug mode - stay in foreground",
 656                     type => "boolean",
 657                     optional => 1,
 658                     default => 0,
 659                 },
 660             },
 661         },
 662         returns => { type => 'null' },
 663
 664         code => sub {
 665             my ($param) = @_;
 666
 667             if (&$init_ppid()) {
 668                 $self->start($param->{debug});
 669             } else {
 670                 PVE::Tools::run_command(['systemctl', 'start', $self->{name}]);
 671             }
 672
 673             return undef;
 674         }});
 675 }
 676
 677 my $reload_daemon = sub {
 678     my ($self, $use_hup) = @_;
 679
 680     if ($self->{env_restart_pve_daemon}) {
 681         $self->start();
 682     } else {
 683         my ($running, $pid) = $self->running();
 684         if (!$running) {
 685             $self->start();
 686         } else {
 687             if ($use_hup) {
 688                 syslog('info', "send HUP to $pid");
 689                 kill 1, $pid;
 690             } else {
 691                 $self->stop();
 692                 $self->start();
 693             }
 694         }
 695     }
 696 };
 697
 698 sub register_restart_command {
 699     my ($self, $use_hup, $description) = @_;
 700
 701     my $class = ref($self);
 702
 703     $class->register_method({
 704         name => 'restart',
 705         path => 'restart',
 706         method => 'POST',
 707         description => $description || "Restart the daemon (or start if not running).",
 708         parameters => {
 709             additionalProperties => 0,
 710             properties => {},
 711         },
 712         returns => { type => 'null' },
 713
 714         code => sub {
 715             my ($param) = @_;
 716
 717             if (&$init_ppid()) {
 718                 &$reload_daemon($self, $use_hup);
 719             } else {
 720                 PVE::Tools::run_command(['systemctl', $use_hup ? 'reload-or-restart' : 'restart', $self->{name}]);
 721             }
 722
 723             return undef;
 724         }});
 725 }
 726
 727 sub register_reload_command {
 728     my ($self, $description) = @_;
 729
 730     my $class = ref($self);
 731
 732     $class->register_method({
 733         name => 'reload',
 734         path => 'reload',
 735         method => 'POST',
 736         description => $description || "Reload daemon configuration (or start if not running).",
 737         parameters => {
 738             additionalProperties => 0,
 739             properties => {},
 740         },
 741         returns => { type => 'null' },
 742
 743         code => sub {
 744             my ($param) = @_;
 745
 746             &$reload_daemon($self, 1);
 747
 748             return undef;
 749         }});
 750 }
 751
 752 sub register_stop_command {
 753     my ($self, $description) = @_;
 754
 755     my $class = ref($self);
 756
 757     $class->register_method({
 758         name => 'stop',
 759         path => 'stop',
 760         method => 'POST',
 761         description => $description || "Stop the daemon.",
 762         parameters => {
 763             additionalProperties => 0,
 764             properties => {},
 765         },
 766         returns => { type => 'null' },
 767
 768         code => sub {
 769             my ($param) = @_;
 770
 771             if (&$init_ppid()) {
 772                 $self->stop();
 773             } else {
 774                 PVE::Tools::run_command(['systemctl', 'stop', $self->{name}]);
 775             }
 776
 777             return undef;
 778         }});
 779 }
 780
 781 sub register_status_command {
 782     my ($self, $description) = @_;
 783
 784     my $class = ref($self);
 785
 786     $class->register_method({
 787         name => 'status',
 788         path => 'status',
 789         method => 'GET',
 790         description => "Get daemon status.",
 791         parameters => {
 792             additionalProperties => 0,
 793             properties => {},
 794         },
 795         returns => {
 796             type => 'string',
 797             enum => ['stopped', 'running'],
 798         },
 799         code => sub {
 800             my ($param) = @_;
 801
 802             return $self->running() ? 'running' : 'stopped';
 803         }});
 804 }
 805
 806 # some useful helper
 807
 808 sub create_reusable_socket {
 809     my ($self, $port, $host, $family) = @_;
 810
 811     die "no port specifed" if !$port;
 812
 813     my ($socket, $sockfd);
 814
 815     if (defined($sockfd = $ENV{"PVE_DAEMON_SOCKET_$port"}) &&
 816         $self->{env_restart_pve_daemon}) {
 817
 818         die "unable to parse socket fd '$sockfd'\n"
 819             if $sockfd !~ m/^(\d+)$/;
 820         $sockfd = $1; # untaint
 821
 822         $socket = IO::Socket::IP->new;
 823         $socket->fdopen($sockfd, 'w') ||
 824             die "cannot fdopen file descriptor '$sockfd' - $!\n";
 825
 826     } else {
 827
 828         $socket = IO::Socket::IP->new(
 829             LocalAddr => $host,
 830             LocalPort => $port,
 831             Listen => SOMAXCONN,
 832             Family => $family,
 833             Proto  => 'tcp',
 834             GetAddrInfoFlags => 0,
 835             ReuseAddr => 1) ||
 836             die "unable to create socket - $@\n";
 837
 838         # we often observe delays when using Nagle algorithm,
 839         # so we disable that to maximize performance
 840         setsockopt($socket, IPPROTO_TCP, TCP_NODELAY, 1);
 841
 842         $ENV{"PVE_DAEMON_SOCKET_$port"} = $socket->fileno;
 843     }
 844
 845     # remove FD_CLOEXEC bit to reuse on exec
 846     $socket->fcntl(Fcntl::F_SETFD(), 0);
 847
 848     return $socket;
 849 }
 850
 851
 852 1;
 853