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Commit | Line | Data |
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390802ab DM |
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 | # * correctly daemonize (redirect STDIN/STDOUT) | |
4fc69176 DM |
9 | # * restart by stop/start, exec, or signal HUP |
10 | # * daemon restart on error (option 'restart_on_error') | |
b2132054 | 11 | # * handle worker processes (option 'max_workers') |
390802ab DM |
12 | |
13 | use strict; | |
14 | use warnings; | |
15 | use PVE::SafeSyslog; | |
16 | use PVE::INotify; | |
17 | ||
18 | use POSIX ":sys_wait_h"; | |
19 | use Fcntl ':flock'; | |
20 | use Getopt::Long; | |
21 | use Time::HiRes qw (gettimeofday); | |
22 | ||
23 | use base qw(PVE::CLIHandler); | |
24 | ||
25 | $SIG{'__WARN__'} = sub { | |
26 | my $err = $@; | |
27 | my $t = $_[0]; | |
28 | chomp $t; | |
29 | print "$t\n"; | |
30 | syslog('warning', "WARNING: %s", $t); | |
31 | $@ = $err; | |
32 | }; | |
33 | ||
34 | $ENV{'PATH'} = '/sbin:/bin:/usr/sbin:/usr/bin'; | |
35 | ||
36 | my $daemon_initialized = 0; # we only allow one instance | |
37 | ||
3206cdf6 DM |
38 | my $close_daemon_lock = sub { |
39 | my ($self) = @_; | |
40 | ||
eead1ad8 DM |
41 | return if !$self->{daemon_lock_fh}; |
42 | ||
3206cdf6 DM |
43 | close $self->{daemon_lock_fh}; |
44 | delete $self->{daemon_lock_fh}; | |
45 | }; | |
46 | ||
eead1ad8 DM |
47 | # call this if you fork() from child |
48 | # Note: we already call this for workers, so it is only required | |
49 | # if you fork inside a simple daemon (max_workers == 0). | |
50 | sub after_fork_cleanup { | |
51 | my ($self) = @_; | |
52 | ||
53 | &$close_daemon_lock($self); | |
54 | ||
55 | PVE::INotify::inotify_close(); | |
56 | ||
57 | for my $sig (qw(CHLD HUP INT TERM QUIT)) { | |
58 | $SIG{$sig} = 'DEFAULT'; # restore default handler | |
59 | # AnyEvent signals only works if $SIG{XX} is | |
60 | # undefined (perl event loop) | |
61 | delete $SIG{$sig}; # so that we can handle events with AnyEvent | |
62 | } | |
63 | } | |
64 | ||
390802ab DM |
65 | my $lockpidfile = sub { |
66 | my ($self) = @_; | |
67 | ||
68 | my $lkfn = $self->{pidfile} . ".lock"; | |
69 | ||
3206cdf6 DM |
70 | $self->{daemon_lock_fh} = IO::File->new(">>$lkfn"); |
71 | if (!$self->{daemon_lock_fh}) { | |
390802ab DM |
72 | my $msg = "can't aquire lock on file '$lkfn' - $!"; |
73 | syslog ('err', $msg); | |
74 | die "ERROR: $msg\n"; | |
75 | } | |
76 | ||
3206cdf6 DM |
77 | for (my $i = 0; $i < 5; $i ++) { |
78 | return if flock ($self->{daemon_lock_fh}, LOCK_EX|LOCK_NB); | |
79 | sleep(1); | |
80 | } | |
81 | ||
82 | if (!flock ($self->{daemon_lock_fh}, LOCK_EX|LOCK_NB)) { | |
83 | &$close_daemon_lock($self); | |
390802ab DM |
84 | my $msg = "can't aquire lock '$lkfn' - $!"; |
85 | syslog ('err', $msg); | |
86 | die "ERROR: $msg\n"; | |
87 | } | |
88 | }; | |
89 | ||
90 | my $writepidfile = sub { | |
91 | my ($self) = @_; | |
92 | ||
93 | my $pidfile = $self->{pidfile}; | |
94 | ||
95 | if (!open (PIDFH, ">$pidfile")) { | |
96 | my $msg = "can't open pid file '$pidfile' - $!"; | |
97 | syslog ('err', $msg); | |
98 | die "ERROR: $msg\n"; | |
99 | } | |
100 | print PIDFH "$$\n"; | |
101 | close (PIDFH); | |
102 | }; | |
103 | ||
104 | my $server_cleanup = sub { | |
105 | my ($self) = @_; | |
106 | ||
107 | unlink $self->{pidfile} . ".lock"; | |
108 | unlink $self->{pidfile}; | |
109 | }; | |
110 | ||
b2132054 DM |
111 | my $finish_workers = sub { |
112 | my ($self) = @_; | |
113 | ||
114 | foreach my $cpid (keys %{$self->{workers}}) { | |
115 | my $waitpid = waitpid($cpid, WNOHANG); | |
116 | if (defined($waitpid) && ($waitpid == $cpid)) { | |
117 | delete ($self->{workers}->{$cpid}); | |
118 | syslog('info', "worker $cpid finished"); | |
119 | } | |
120 | } | |
121 | }; | |
122 | ||
123 | my $start_workers = sub { | |
124 | my ($self) = @_; | |
125 | ||
126 | return if $self->{terminate}; | |
127 | ||
128 | my $count = 0; | |
129 | foreach my $cpid (keys %{$self->{workers}}) { | |
130 | $count++; | |
131 | } | |
132 | ||
133 | my $need = $self->{max_workers} - $count; | |
134 | ||
135 | return if $need <= 0; | |
136 | ||
137 | syslog('info', "starting $need worker(s)"); | |
138 | ||
139 | while ($need > 0) { | |
140 | my $pid = fork; | |
141 | ||
142 | if (!defined ($pid)) { | |
143 | syslog('err', "can't fork worker"); | |
144 | sleep (1); | |
145 | } elsif ($pid) { # parent | |
146 | $self->{workers}->{$pid} = 1; | |
147 | syslog('info', "worker $pid started"); | |
148 | $need--; | |
149 | } else { | |
150 | $0 = "$self->{name} worker"; | |
151 | ||
eead1ad8 | 152 | $self->after_fork_cleanup(); |
b2132054 DM |
153 | |
154 | eval { $self->run(); }; | |
155 | if (my $err = $@) { | |
156 | syslog('err', $err); | |
157 | sleep(5); # avoid fast restarts | |
158 | } | |
159 | ||
160 | syslog('info', "worker exit"); | |
161 | exit (0); | |
162 | } | |
163 | } | |
164 | }; | |
165 | ||
166 | my $terminate_server = sub { | |
167 | my ($self) = @_; | |
168 | ||
169 | $self->{terminate} = 1; # set flag to avoid worker restart | |
170 | ||
171 | if (!$self->{max_workers}) { | |
172 | eval { $self->shutdown(); }; | |
173 | warn $@ if $@; | |
174 | return; | |
175 | } | |
176 | ||
177 | eval { $self->shutdown(); }; | |
178 | warn $@ if $@; | |
179 | ||
180 | # we have workers - terminate them | |
181 | ||
182 | foreach my $cpid (keys %{$self->{workers}}) { | |
183 | kill(15, $cpid); # TERM childs | |
184 | } | |
185 | ||
186 | # nicely shutdown childs (give them max 10 seconds to shut down) | |
187 | my $previous_alarm = alarm(10); | |
188 | eval { | |
189 | local $SIG{ALRM} = sub { die "timeout\n" }; | |
190 | ||
191 | while ((my $pid = waitpid (-1, 0)) > 0) { | |
192 | if (defined($self->{workers}->{$pid})) { | |
193 | delete($self->{workers}->{$pid}); | |
194 | syslog('info', "worker $pid finished"); | |
195 | } | |
196 | } | |
197 | alarm(0); # avoid race condition | |
198 | }; | |
199 | my $err = $@; | |
200 | ||
201 | alarm ($previous_alarm); | |
202 | ||
203 | if ($err) { | |
204 | syslog('err', "error stopping workers (will kill them now) - $err"); | |
205 | foreach my $cpid (keys %{$self->{workers}}) { | |
206 | # KILL childs still alive! | |
207 | if (kill (0, $cpid)) { | |
208 | delete($self->{workers}->{$cpid}); | |
209 | syslog("err", "kill worker $cpid"); | |
210 | kill(9, $cpid); | |
211 | # fixme: waitpid? | |
212 | } | |
213 | } | |
214 | } | |
215 | }; | |
216 | ||
390802ab DM |
217 | my $server_run = sub { |
218 | my ($self, $debug) = @_; | |
219 | ||
220 | &$lockpidfile($self); | |
221 | ||
222 | # run in background | |
223 | my $spid; | |
224 | ||
225 | my $restart = $ENV{RESTART_PVE_DAEMON}; | |
226 | ||
227 | delete $ENV{RESTART_PVE_DAEMON}; | |
228 | ||
229 | $self->{debug} = 1 if $debug; | |
230 | ||
231 | $self->init(); | |
232 | ||
233 | if (!$debug) { | |
234 | open STDIN, '</dev/null' || die "can't read /dev/null"; | |
235 | open STDOUT, '>/dev/null' || die "can't write /dev/null"; | |
236 | } | |
237 | ||
238 | if (!$restart && !$debug) { | |
239 | PVE::INotify::inotify_close(); | |
240 | $spid = fork(); | |
241 | if (!defined ($spid)) { | |
242 | my $msg = "can't put server into background - fork failed"; | |
243 | syslog('err', $msg); | |
244 | die "ERROR: $msg\n"; | |
245 | } elsif ($spid) { # parent | |
246 | exit (0); | |
247 | } | |
248 | PVE::INotify::inotify_init(); | |
249 | } | |
250 | ||
251 | &$writepidfile($self); | |
252 | ||
891b9097 DM |
253 | POSIX::setsid(); |
254 | ||
390802ab DM |
255 | if ($restart) { |
256 | syslog('info' , "restarting server"); | |
257 | } else { | |
258 | syslog('info' , "starting server"); | |
259 | } | |
260 | ||
261 | open STDERR, '>&STDOUT' || die "can't close STDERR\n"; | |
262 | ||
b2132054 DM |
263 | my $old_sig_term = $SIG{TERM}; |
264 | local $SIG{TERM} = sub { | |
265 | local ($@, $!, $?); # do not overwrite error vars | |
266 | syslog('info', "received signal TERM"); | |
267 | &$terminate_server($self); | |
268 | &$server_cleanup($self); | |
269 | &$old_sig_term(@_) if $old_sig_term; | |
270 | }; | |
390802ab | 271 | |
b2132054 DM |
272 | my $old_sig_quit = $SIG{QUIT}; |
273 | local $SIG{QUIT} = sub { | |
274 | local ($@, $!, $?); # do not overwrite error vars | |
275 | syslog('info', "received signal QUIT"); | |
276 | &$terminate_server($self); | |
277 | &$server_cleanup($self); | |
278 | &$old_sig_quit(@_) if $old_sig_quit; | |
279 | }; | |
390802ab | 280 | |
b2132054 DM |
281 | my $old_sig_int = $SIG{INT}; |
282 | local $SIG{INT} = sub { | |
283 | local ($@, $!, $?); # do not overwrite error vars | |
284 | syslog('info', "received signal INT"); | |
285 | $SIG{INT} = 'DEFAULT'; # allow to terminate now | |
286 | &$terminate_server($self); | |
390802ab | 287 | &$server_cleanup($self); |
b2132054 | 288 | &$old_sig_int(@_) if $old_sig_int; |
390802ab DM |
289 | }; |
290 | ||
b2132054 DM |
291 | $SIG{HUP} = sub { |
292 | local ($@, $!, $?); # do not overwrite error vars | |
293 | syslog('info', "received signal HUP"); | |
294 | if ($self->{max_workers}) { | |
295 | &$terminate_server($self); | |
296 | $self->{got_hup_signal} = 1; | |
297 | } elsif ($self->can('hup')) { | |
bdb5acce DM |
298 | eval { $self->hup() }; |
299 | warn $@ if $@; | |
b2132054 DM |
300 | } |
301 | }; | |
302 | ||
303 | eval { | |
304 | if ($self->{max_workers}) { | |
305 | my $old_sig_chld = $SIG{CHLD}; | |
306 | local $SIG{CHLD} = sub { | |
307 | local ($@, $!, $?); # do not overwrite error vars | |
308 | &$finish_workers($self); | |
309 | &$old_sig_chld(@_) if $old_sig_chld; | |
310 | }; | |
311 | ||
312 | for (;;) { # forever | |
313 | &$start_workers($self); | |
314 | sleep(5); | |
315 | &$finish_workers($self); | |
316 | last if $self->{terminate}; | |
317 | } | |
bdb5acce | 318 | |
b2132054 DM |
319 | } else { |
320 | $self->run(); | |
321 | } | |
322 | }; | |
390802ab DM |
323 | my $err = $@; |
324 | ||
325 | if ($err) { | |
326 | syslog ('err', "ERROR: $err"); | |
b2132054 DM |
327 | |
328 | # fixme: kill all workers | |
329 | ||
390802ab DM |
330 | if (my $wait_time = $self->{restart_on_error}) { |
331 | $self->restart_daemon($wait_time); | |
332 | } else { | |
333 | $self->exit_daemon(-1); | |
334 | } | |
335 | } | |
336 | ||
b2132054 DM |
337 | if ($self->{got_hup_signal}) { |
338 | $self->restart_daemon(); | |
339 | } else { | |
340 | $self->exit_daemon(0); | |
341 | } | |
390802ab DM |
342 | }; |
343 | ||
344 | sub new { | |
345 | my ($this, $name, $cmdline, %params) = @_; | |
346 | ||
b2132054 | 347 | die "please run as root\n" if !$ENV{RESTART_PVE_DAEMON} && ($> != 0); |
390802ab DM |
348 | |
349 | die "missing name" if !$name; | |
350 | ||
351 | die "can't create more that one PVE::Daemon" if $daemon_initialized; | |
352 | $daemon_initialized = 1; | |
353 | ||
354 | PVE::INotify::inotify_init(); | |
355 | ||
356 | initlog($name); | |
357 | ||
358 | my $class = ref($this) || $this; | |
359 | ||
bdb5acce DM |
360 | my $self = bless { |
361 | name => $name, | |
362 | run_dir => '/var/run', | |
b2132054 | 363 | workers => {}, |
bdb5acce | 364 | }, $class; |
390802ab DM |
365 | |
366 | foreach my $opt (keys %params) { | |
367 | my $value = $params{$opt}; | |
368 | if ($opt eq 'restart_on_error') { | |
369 | $self->{$opt} = $value; | |
370 | } elsif ($opt eq 'stop_wait_time') { | |
371 | $self->{$opt} = $value; | |
bdb5acce DM |
372 | } elsif ($opt eq 'run_dir') { |
373 | $self->{$opt} = $value; | |
b2132054 DM |
374 | } elsif ($opt eq 'max_workers') { |
375 | $self->{$opt} = $value; | |
390802ab DM |
376 | } else { |
377 | die "unknown option '$opt'"; | |
378 | } | |
379 | } | |
380 | ||
bdb5acce DM |
381 | $self->{pidfile} = "$self->{run_dir}/${name}.pid"; |
382 | ||
383 | $self->{nodename} = PVE::INotify::nodename(); | |
384 | ||
b2132054 | 385 | $self->{cmdline} = []; |
bdb5acce | 386 | |
b2132054 DM |
387 | foreach my $el (@$cmdline) { |
388 | $el =~ m/^(.*)$/; # untaint | |
389 | push @{$self->{cmdline}}, $1; | |
390 | } | |
bdb5acce | 391 | |
b2132054 | 392 | $0 = $name; |
bdb5acce | 393 | |
390802ab DM |
394 | return $self; |
395 | } | |
396 | ||
397 | sub exit_daemon { | |
398 | my ($self, $status) = @_; | |
399 | ||
400 | syslog("info", "server stopped"); | |
401 | ||
402 | &$server_cleanup($self); | |
403 | ||
404 | exit($status); | |
405 | } | |
406 | ||
407 | sub restart_daemon { | |
408 | my ($self, $waittime) = @_; | |
409 | ||
410 | syslog('info', "server shutdown (restart)"); | |
411 | ||
412 | $ENV{RESTART_PVE_DAEMON} = 1; | |
413 | ||
414 | sleep($waittime) if $waittime; # avoid high server load due to restarts | |
415 | ||
416 | PVE::INotify::inotify_close(); | |
417 | ||
418 | exec (@{$self->{cmdline}}); | |
419 | ||
420 | exit (-1); # never reached? | |
421 | } | |
422 | ||
423 | # please overwrite in subclass | |
424 | # this is called at startup - before forking | |
425 | sub init { | |
426 | my ($self) = @_; | |
427 | ||
428 | } | |
429 | ||
430 | # please overwrite in subclass | |
431 | sub shutdown { | |
432 | my ($self) = @_; | |
433 | ||
434 | syslog('info' , "server closing"); | |
435 | ||
b2132054 DM |
436 | if (!$self->{max_workers}) { |
437 | # wait for children | |
438 | 1 while (waitpid(-1, POSIX::WNOHANG()) > 0); | |
439 | } | |
390802ab DM |
440 | } |
441 | ||
bdb5acce DM |
442 | # please define in subclass |
443 | #sub hup { | |
444 | # my ($self) = @_; | |
445 | # | |
446 | # syslog('info' , "received signal HUP (restart)"); | |
447 | #} | |
390802ab DM |
448 | |
449 | # please overwrite in subclass | |
450 | sub run { | |
451 | my ($self) = @_; | |
452 | ||
453 | for (;;) { # forever | |
454 | syslog('info' , "server is running"); | |
455 | sleep(5); | |
456 | } | |
457 | } | |
458 | ||
459 | sub start { | |
460 | my ($self, $debug) = @_; | |
461 | ||
462 | &$server_run($self, $debug); | |
463 | } | |
464 | ||
bdb5acce DM |
465 | my $read_pid = sub { |
466 | my ($self) = @_; | |
467 | ||
468 | my $pid_str = PVE::Tools::file_read_firstline($self->{pidfile}); | |
469 | ||
470 | return 0 if !$pid_str; | |
471 | ||
472 | return 0 if $pid_str !~ m/^(\d+)$/; # untaint | |
473 | ||
474 | my $pid = int($1); | |
475 | ||
476 | return $pid; | |
477 | }; | |
478 | ||
390802ab DM |
479 | sub running { |
480 | my ($self) = @_; | |
481 | ||
bdb5acce | 482 | my $pid = &$read_pid($self); |
390802ab DM |
483 | |
484 | if ($pid) { | |
485 | my $res = PVE::ProcFSTools::check_process_running($pid) ? 1 : 0; | |
486 | return wantarray ? ($res, $pid) : $res; | |
487 | } | |
488 | ||
489 | return wantarray ? (0, 0) : 0; | |
490 | } | |
491 | ||
492 | sub stop { | |
493 | my ($self) = @_; | |
494 | ||
bdb5acce DM |
495 | my $pid = &$read_pid($self); |
496 | ||
390802ab DM |
497 | return if !$pid; |
498 | ||
499 | if (PVE::ProcFSTools::check_process_running($pid)) { | |
500 | kill(15, $pid); # send TERM signal | |
501 | # give some time | |
502 | my $wait_time = $self->{stop_wait_time} || 5; | |
503 | my $running = 1; | |
504 | for (my $i = 0; $i < $wait_time; $i++) { | |
505 | $running = PVE::ProcFSTools::check_process_running($pid); | |
506 | last if !$running; | |
507 | sleep (1); | |
508 | } | |
509 | ||
510 | syslog('err', "server still running - send KILL") if $running; | |
511 | ||
512 | # to be sure | |
513 | kill(9, $pid); | |
514 | waitpid($pid, 0); | |
515 | } | |
516 | ||
517 | if (-f $self->{pidfile}) { | |
518 | # try to get the lock | |
519 | &$lockpidfile($self); | |
520 | &$server_cleanup($self); | |
521 | } | |
522 | } | |
523 | ||
524 | sub register_start_command { | |
525 | my ($self, $class, $description) = @_; | |
526 | ||
527 | $class->register_method({ | |
528 | name => 'start', | |
529 | path => 'start', | |
530 | method => 'POST', | |
531 | description => $description || "Start the daemon.", | |
532 | parameters => { | |
533 | additionalProperties => 0, | |
534 | properties => { | |
535 | debug => { | |
536 | description => "Debug mode - stay in foreground", | |
537 | type => "boolean", | |
538 | optional => 1, | |
539 | default => 0, | |
540 | }, | |
541 | }, | |
542 | }, | |
543 | returns => { type => 'null' }, | |
544 | ||
545 | code => sub { | |
546 | my ($param) = @_; | |
547 | ||
548 | $self->start($param->{debug}); | |
549 | ||
550 | return undef; | |
551 | }}); | |
552 | } | |
553 | ||
bdb5acce DM |
554 | my $reload_daemon = sub { |
555 | my ($self, $use_hup) = @_; | |
556 | ||
557 | if (my $restart = $ENV{RESTART_PVE_DAEMON}) { | |
558 | $self->start(); | |
559 | } else { | |
560 | my ($running, $pid) = $self->running(); | |
561 | if (!$running) { | |
562 | $self->start(); | |
563 | } else { | |
564 | if ($use_hup) { | |
b2132054 DM |
565 | syslog('info', "send HUP to $pid"); |
566 | kill 1, $pid; | |
bdb5acce DM |
567 | } else { |
568 | $self->stop(); | |
569 | $self->start(); | |
570 | } | |
571 | } | |
572 | } | |
573 | }; | |
574 | ||
390802ab | 575 | sub register_restart_command { |
bdb5acce | 576 | my ($self, $class, $use_hup, $description) = @_; |
390802ab DM |
577 | |
578 | $class->register_method({ | |
579 | name => 'restart', | |
580 | path => 'restart', | |
581 | method => 'POST', | |
582 | description => $description || "Restart the daemon (or start if not running).", | |
583 | parameters => { | |
584 | additionalProperties => 0, | |
585 | properties => {}, | |
586 | }, | |
587 | returns => { type => 'null' }, | |
588 | ||
589 | code => sub { | |
590 | my ($param) = @_; | |
591 | ||
bdb5acce DM |
592 | &$reload_daemon($self, $use_hup); |
593 | ||
594 | return undef; | |
595 | }}); | |
596 | } | |
597 | ||
598 | sub register_reload_command { | |
599 | my ($self, $class, $description) = @_; | |
600 | ||
601 | $class->register_method({ | |
602 | name => 'reload', | |
603 | path => 'reload', | |
604 | method => 'POST', | |
605 | description => $description || "Reload daemon configuration (or start if not running).", | |
606 | parameters => { | |
607 | additionalProperties => 0, | |
608 | properties => {}, | |
609 | }, | |
610 | returns => { type => 'null' }, | |
611 | ||
612 | code => sub { | |
613 | my ($param) = @_; | |
614 | ||
615 | &$reload_daemon($self, 1); | |
390802ab DM |
616 | |
617 | return undef; | |
618 | }}); | |
619 | } | |
620 | ||
621 | sub register_stop_command { | |
622 | my ($self, $class, $description) = @_; | |
623 | ||
624 | $class->register_method({ | |
625 | name => 'stop', | |
626 | path => 'stop', | |
627 | method => 'POST', | |
628 | description => $description || "Stop the daemon.", | |
629 | parameters => { | |
630 | additionalProperties => 0, | |
631 | properties => {}, | |
632 | }, | |
633 | returns => { type => 'null' }, | |
634 | ||
635 | code => sub { | |
636 | my ($param) = @_; | |
637 | ||
638 | $self->stop(); | |
639 | ||
640 | return undef; | |
641 | }}); | |
642 | } | |
643 | ||
644 | sub register_status_command { | |
645 | my ($self, $class, $description) = @_; | |
646 | ||
647 | $class->register_method({ | |
648 | name => 'status', | |
649 | path => 'status', | |
650 | method => 'GET', | |
651 | description => "Get daemon status.", | |
652 | parameters => { | |
653 | additionalProperties => 0, | |
654 | properties => {}, | |
655 | }, | |
656 | returns => { | |
657 | type => 'string', | |
658 | enum => ['stopped', 'running'], | |
659 | }, | |
660 | code => sub { | |
661 | my ($param) = @_; | |
662 | ||
663 | return $self->running() ? 'running' : 'stopped'; | |
664 | }}); | |
665 | } | |
666 | ||
667 | 1; | |
668 |