1 # Copyright (C) 2015 all contributors <meta@public-inbox.org>
2 # License: AGPLv3 or later (https://www.gnu.org/licenses/agpl-3.0.txt)
3 # contains common daemon code for the nntpd and httpd servers.
4 # This may be used for read-only IMAP server if we decide to implement it.
5 package PublicInbox::Daemon;
8 use Getopt::Long qw/:config gnu_getopt no_ignore_case auto_abbrev/;
13 require Danga::Socket;
15 require PublicInbox::Listener;
18 my (@cfg_listen, $stdout, $stderr, $group, $user, $pid_file, $daemonize);
19 my $worker_processes = 1;
26 END { $cleanup->() if $cleanup };
28 sub daemon_prepare ($) {
29 my ($default_listen) = @_;
31 $SIG{HUP} = $SIG{USR1} = $SIG{USR2} = $SIG{PIPE} =
32 $SIG{TTIN} = $SIG{TTOU} = $SIG{WINCH} = 'IGNORE';
34 'l|listen=s' => \@cfg_listen,
35 '1|stdout=s' => \$stdout,
36 '2|stderr=s' => \$stderr,
37 'W|worker-processes=i' => \$worker_processes,
38 'P|pid-file=s' => \$pid_file,
40 'g|group=s' => \$group,
41 'D|daemonize' => \$daemonize,
43 GetOptions(%opts) or die "bad command-line args\n";
45 if (defined $pid_file && $pid_file =~ /\.oldbin\z/) {
46 die "--pid-file cannot end with '.oldbin'\n";
48 @listeners = inherit();
49 # ignore daemonize when inheriting
50 $daemonize = undef if scalar @listeners;
52 push @cfg_listen, $default_listen unless (@listeners || @cfg_listen);
54 foreach my $l (@cfg_listen) {
55 next if $listener_names{$l}; # already inherited
57 if (index($l, '/') == 0) {
58 $sock_pkg = 'IO::Socket::UNIX';
61 %o = (Type => SOCK_STREAM, Peer => $l);
63 my $c = $sock_pkg->new(%o);
64 if (!defined($c) && $!{ECONNREFUSED}) {
66 "failed to unlink stale socket=$l: $!\n";
67 } # else: let the bind fail
69 $o{Local} = delete $o{Peer};
71 $sock_pkg = 'IO::Socket::INET6'; # works for IPv4, too
74 %o = (LocalAddr => $l, ReuseAddr => 1, Proto => 'tcp');
77 my $prev = umask 0000;
78 my $s = eval { $sock_pkg->new(%o) };
79 warn "error binding $l: $!\n" unless $s;
83 $listener_names{sockname($s)} = $s;
87 die "No listeners bound\n" unless @listeners;
91 chdir '/' or die "chdir failed: $!";
92 open(STDIN, '+<', '/dev/null') or die "redirect stdin failed: $!";
94 return unless (defined $pid_file || defined $group || defined $user
97 eval { require Net::Server::Daemonize };
100 "Net::Server required for --pid-file, --group, --user, and --daemonize\n$@\n";
103 Net::Server::Daemonize::check_pid_file($pid_file) if defined $pid_file;
104 $uid = Net::Server::Daemonize::get_uid($user) if defined $user;
105 if (defined $group) {
106 $gid = Net::Server::Daemonize::get_gid($group);
107 $gid = (split /\s+/, $gid)[0];
108 } elsif (defined $uid) {
109 $gid = (getpwuid($uid))[3];
112 # We change users in the worker to ensure upgradability,
113 # The upgrade will create the ".oldbin" pid file in the
114 # same directory as the given pid file.
115 $uid and $set_user = sub {
117 Net::Server::Daemonize::set_user($uid, $gid);
121 my ($pid, $err) = do_fork();
122 die "could not fork: $err\n" unless defined $pid;
125 open STDOUT, '>&STDIN' or die "redirect stdout failed: $!\n";
126 open STDERR, '>&STDIN' or die "redirect stderr failed: $!\n";
128 ($pid, $err) = do_fork();
129 die "could not fork: $err\n" unless defined $pid;
132 if (defined $pid_file) {
133 write_pid($pid_file);
136 $cleanup = undef; # avoid cyclic reference
137 unlink_pid_file_safe_ish($unlink_pid, $pid_file);
143 # killing again terminates immediately:
144 exit unless @listeners;
146 $_->close foreach @listeners; # call Danga::Socket::close
149 # give slow clients 30s to finish reading/writing whatever
150 Danga::Socket->AddTimer(30, sub { exit });
152 # drop idle connections and try to quit gracefully
153 Danga::Socket->SetPostLoopCallback(sub {
154 my ($dmap, undef) = @_;
157 foreach my $s (values %$dmap) {
158 if ($s->can('busy') && $s->busy) {
161 # close as much as possible, early as possible
165 $n; # true: loop continues, false: loop breaks
171 open STDOUT, '>>', $stdout or
172 warn "failed to redirect stdout to $stdout: $!\n";
173 STDOUT->autoflush(1);
177 open STDERR, '>>', $stderr or
178 warn "failed to redirect stderr to $stderr: $!\n";
179 STDERR->autoflush(1);
186 my $addr = getsockname($s) or return;
187 my ($host, $port) = host_with_port($addr);
191 sub host_with_port ($) {
195 # this eval will die on Unix sockets:
197 if (length($addr) >= 28) {
199 ($port, $host) = Socket6::unpack_sockaddr_in6($addr);
200 $host = Socket6::inet_ntop(Socket6::AF_INET6(), $host);
203 ($port, $host) = Socket::sockaddr_in($addr);
204 $host = Socket::inet_ntoa($host);
207 $@ ? ('127.0.0.1', 0) : ($host, $port);
211 return () if ($ENV{LISTEN_PID} || 0) != $$;
212 my $fds = $ENV{LISTEN_FDS} or return ();
213 my $end = $fds + 2; # LISTEN_FDS_START - 1
215 foreach my $fd (3..$end) {
216 my $s = IO::Handle->new_from_fd($fd, 'r');
217 if (my $k = sockname($s)) {
218 $listener_names{$k} = $s;
221 warn "failed to inherit fd=$fd (LISTEN_FDS=$fds)";
229 warn "upgrade in-progress: $reexec_pid\n";
232 if (defined $pid_file) {
233 if ($pid_file =~ /\.oldbin\z/) {
234 warn "BUG: .oldbin suffix exists: $pid_file\n";
237 unlink_pid_file_safe_ish($$, $pid_file);
238 $pid_file .= '.oldbin';
239 write_pid($pid_file);
241 my ($pid, $err) = do_fork();
242 unless (defined $pid) {
243 warn "fork failed: $err\n";
247 use Fcntl qw(FD_CLOEXEC F_SETFD F_GETFD);
248 $ENV{LISTEN_FDS} = scalar @listeners;
249 $ENV{LISTEN_PID} = $$;
250 foreach my $s (@listeners) {
251 my $fl = fcntl($s, F_GETFD, 0);
252 fcntl($s, F_SETFD, $fl &= ~FD_CLOEXEC);
255 die "Failed to exec: $!\n";
260 sub kill_workers ($) {
263 while (my ($pid, $id) = each %pids) {
269 my $new = POSIX::SigSet->new;
271 my $old = POSIX::SigSet->new;
272 POSIX::sigprocmask(&POSIX::SIG_BLOCK, $new, $old) or die "SIG_BLOCK: $!";
275 POSIX::sigprocmask(&POSIX::SIG_SETMASK, $old) or die "SIG_SETMASK: $!";
279 sub upgrade_aborted ($) {
281 warn "reexec PID($p) died with: $?\n";
283 return unless $pid_file;
285 my $file = $pid_file;
286 $file =~ s/\.oldbin\z// or die "BUG: no '.oldbin' suffix in $file";
287 unlink_pid_file_safe_ish($$, $pid_file);
289 eval { write_pid($pid_file) };
293 sub reap_children () {
295 my $p = waitpid(-1, &POSIX::WNOHANG) or return;
296 if (defined $reexec_pid && $p == $reexec_pid) {
298 } elsif (defined(my $id = delete $pids{$p})) {
299 warn "worker[$id] PID($p) died with: $?\n";
301 warn "unknown PID($p) reaped: $?\n";
308 sub unlink_pid_file_safe_ish ($$) {
309 my ($unlink_pid, $file) = @_;
310 return unless defined $unlink_pid && $unlink_pid == $$;
312 open my $fh, '<', $file or return;
313 defined(my $read_pid = <$fh>) or return;
315 if ($read_pid == $unlink_pid) {
316 Net::Server::Daemonize::unlink_pid_file($file);
321 pipe(my ($p0, $p1)) or die "failed to create parent-pipe: $!";
322 pipe(my ($r, $w)) or die "failed to create self-pipe: $!";
323 IO::Handle::blocking($w, 0);
324 my $set_workers = $worker_processes;
327 foreach my $s (qw(HUP CHLD QUIT INT TERM USR1 USR2 TTIN TTOU WINCH)) {
329 return if $$ != $master_pid;
337 while (my $s = shift @caught) {
341 } elsif ($s eq 'USR2') {
343 } elsif ($s =~ /\A(?:QUIT|TERM|INT)\z/) {
344 # drops pipes and causes children to die
346 } elsif ($s eq 'WINCH') {
347 $worker_processes = 0;
348 } elsif ($s eq 'HUP') {
349 $worker_processes = $set_workers;
351 } elsif ($s eq 'TTIN') {
352 if ($set_workers > $worker_processes) {
355 $worker_processes = ++$set_workers;
357 } elsif ($s eq 'TTOU') {
358 if ($set_workers > 0) {
359 $worker_processes = --$set_workers;
361 } elsif ($s eq 'CHLD') {
366 my $n = scalar keys %pids;
367 if ($n > $worker_processes) {
368 while (my ($k, $v) = each %pids) {
369 kill('TERM', $k) if $v >= $worker_processes;
371 $n = $worker_processes;
373 foreach my $i ($n..($worker_processes - 1)) {
374 my ($pid, $err) = do_fork();
376 warn "failed to fork worker[$i]: $err\n";
377 } elsif ($pid == 0) {
378 $set_user->() if $set_user;
379 return $p0; # run normal work code
381 warn "PID=$pid is worker[$i]\n";
385 # just wait on signal events here:
386 sysread($r, my $buf, 8);
388 exit # never gets here, just for documentation
391 sub daemon_loop ($$) {
392 my ($refresh, $post_accept) = @_;
394 if ($worker_processes > 0) {
395 $refresh->(); # preload by default
396 $parent_pipe = master_loop(); # returns if in child process
397 my $fd = fileno($parent_pipe);
398 Danga::Socket->AddOtherFds($fd => *worker_quit);
401 $set_user->() if $set_user;
402 $SIG{USR2} = sub { worker_quit() if upgrade() };
407 $SIG{QUIT} = $SIG{INT} = $SIG{TERM} = *worker_quit;
408 $SIG{USR1} = *reopen_logs;
409 $SIG{HUP} = $refresh;
410 # this calls epoll_create:
412 PublicInbox::Listener->new($_, $post_accept)
414 Danga::Socket->EventLoop;
415 $parent_pipe = undef;
420 my ($default, $refresh, $post_accept) = @_;
421 daemon_prepare($default);
423 daemon_loop($refresh, $post_accept);
428 if (defined $uid and !chown($uid, $gid, $path)) {
429 warn "could not chown $path: $!\n";
435 Net::Server::Daemonize::create_pid_file($path);