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 # both work for IPv4, too
72 for $sock_pkg (qw(IO::Socket::IP IO::Socket::INET6)) {
77 %o = (LocalAddr => $l, ReuseAddr => 1, Proto => 'tcp');
80 my $prev = umask 0000;
81 my $s = eval { $sock_pkg->new(%o) };
82 warn "error binding $l: $!\n" unless $s;
86 $listener_names{sockname($s)} = $s;
90 die "No listeners bound\n" unless @listeners;
94 chdir '/' or die "chdir failed: $!";
95 open(STDIN, '+<', '/dev/null') or die "redirect stdin failed: $!";
97 return unless (defined $pid_file || defined $group || defined $user
100 eval { require Net::Server::Daemonize };
103 "Net::Server required for --pid-file, --group, --user, and --daemonize\n$@\n";
106 Net::Server::Daemonize::check_pid_file($pid_file) if defined $pid_file;
107 $uid = Net::Server::Daemonize::get_uid($user) if defined $user;
108 if (defined $group) {
109 $gid = Net::Server::Daemonize::get_gid($group);
110 $gid = (split /\s+/, $gid)[0];
111 } elsif (defined $uid) {
112 $gid = (getpwuid($uid))[3];
115 # We change users in the worker to ensure upgradability,
116 # The upgrade will create the ".oldbin" pid file in the
117 # same directory as the given pid file.
118 $uid and $set_user = sub {
120 Net::Server::Daemonize::set_user($uid, $gid);
124 my ($pid, $err) = do_fork();
125 die "could not fork: $err\n" unless defined $pid;
128 open STDOUT, '>&STDIN' or die "redirect stdout failed: $!\n";
129 open STDERR, '>&STDIN' or die "redirect stderr failed: $!\n";
131 ($pid, $err) = do_fork();
132 die "could not fork: $err\n" unless defined $pid;
135 if (defined $pid_file) {
136 write_pid($pid_file);
139 $cleanup = undef; # avoid cyclic reference
140 unlink_pid_file_safe_ish($unlink_pid, $pid_file);
146 # killing again terminates immediately:
147 exit unless @listeners;
149 $_->close foreach @listeners; # call Danga::Socket::close
152 # give slow clients 30s to finish reading/writing whatever
153 Danga::Socket->AddTimer(30, sub { exit });
155 # drop idle connections and try to quit gracefully
156 Danga::Socket->SetPostLoopCallback(sub {
157 my ($dmap, undef) = @_;
160 foreach my $s (values %$dmap) {
161 if ($s->can('busy') && $s->busy) {
164 # close as much as possible, early as possible
168 $n; # true: loop continues, false: loop breaks
174 open STDOUT, '>>', $stdout or
175 warn "failed to redirect stdout to $stdout: $!\n";
176 STDOUT->autoflush(1);
180 open STDERR, '>>', $stderr or
181 warn "failed to redirect stderr to $stderr: $!\n";
182 STDERR->autoflush(1);
189 my $addr = getsockname($s) or return;
190 my ($host, $port) = host_with_port($addr);
191 if ($port == 0 && $host eq '127.0.0.1') {
192 my ($path) = Socket::sockaddr_un($addr);
198 sub host_with_port ($) {
202 # this eval will die on Unix sockets:
204 if (length($addr) >= 28) {
206 ($port, $host) = Socket6::unpack_sockaddr_in6($addr);
207 $host = Socket6::inet_ntop(Socket6::AF_INET6(), $host);
210 ($port, $host) = Socket::sockaddr_in($addr);
211 $host = Socket::inet_ntoa($host);
214 $@ ? ('127.0.0.1', 0) : ($host, $port);
218 return () if ($ENV{LISTEN_PID} || 0) != $$;
219 my $fds = $ENV{LISTEN_FDS} or return ();
220 my $end = $fds + 2; # LISTEN_FDS_START - 1
222 foreach my $fd (3..$end) {
223 my $s = IO::Handle->new_from_fd($fd, 'r');
224 if (my $k = sockname($s)) {
225 $listener_names{$k} = $s;
228 warn "failed to inherit fd=$fd (LISTEN_FDS=$fds)";
236 warn "upgrade in-progress: $reexec_pid\n";
239 if (defined $pid_file) {
240 if ($pid_file =~ /\.oldbin\z/) {
241 warn "BUG: .oldbin suffix exists: $pid_file\n";
244 unlink_pid_file_safe_ish($$, $pid_file);
245 $pid_file .= '.oldbin';
246 write_pid($pid_file);
248 my ($pid, $err) = do_fork();
249 unless (defined $pid) {
250 warn "fork failed: $err\n";
254 use Fcntl qw(FD_CLOEXEC F_SETFD F_GETFD);
255 $ENV{LISTEN_FDS} = scalar @listeners;
256 $ENV{LISTEN_PID} = $$;
257 foreach my $s (@listeners) {
258 my $fl = fcntl($s, F_GETFD, 0);
259 fcntl($s, F_SETFD, $fl &= ~FD_CLOEXEC);
262 die "Failed to exec: $!\n";
267 sub kill_workers ($) {
270 while (my ($pid, $id) = each %pids) {
276 my $new = POSIX::SigSet->new;
278 my $old = POSIX::SigSet->new;
279 POSIX::sigprocmask(&POSIX::SIG_BLOCK, $new, $old) or die "SIG_BLOCK: $!";
282 POSIX::sigprocmask(&POSIX::SIG_SETMASK, $old) or die "SIG_SETMASK: $!";
286 sub upgrade_aborted ($) {
288 warn "reexec PID($p) died with: $?\n";
290 return unless $pid_file;
292 my $file = $pid_file;
293 $file =~ s/\.oldbin\z// or die "BUG: no '.oldbin' suffix in $file";
294 unlink_pid_file_safe_ish($$, $pid_file);
296 eval { write_pid($pid_file) };
300 sub reap_children () {
302 my $p = waitpid(-1, &POSIX::WNOHANG) or return;
303 if (defined $reexec_pid && $p == $reexec_pid) {
305 } elsif (defined(my $id = delete $pids{$p})) {
306 warn "worker[$id] PID($p) died with: $?\n";
308 warn "unknown PID($p) reaped: $?\n";
315 sub unlink_pid_file_safe_ish ($$) {
316 my ($unlink_pid, $file) = @_;
317 return unless defined $unlink_pid && $unlink_pid == $$;
319 open my $fh, '<', $file or return;
320 defined(my $read_pid = <$fh>) or return;
322 if ($read_pid == $unlink_pid) {
323 Net::Server::Daemonize::unlink_pid_file($file);
328 pipe(my ($p0, $p1)) or die "failed to create parent-pipe: $!";
329 pipe(my ($r, $w)) or die "failed to create self-pipe: $!";
330 IO::Handle::blocking($w, 0);
331 my $set_workers = $worker_processes;
334 foreach my $s (qw(HUP CHLD QUIT INT TERM USR1 USR2 TTIN TTOU WINCH)) {
336 return if $$ != $master_pid;
344 while (my $s = shift @caught) {
348 } elsif ($s eq 'USR2') {
350 } elsif ($s =~ /\A(?:QUIT|TERM|INT)\z/) {
351 # drops pipes and causes children to die
353 } elsif ($s eq 'WINCH') {
354 $worker_processes = 0;
355 } elsif ($s eq 'HUP') {
356 $worker_processes = $set_workers;
358 } elsif ($s eq 'TTIN') {
359 if ($set_workers > $worker_processes) {
362 $worker_processes = ++$set_workers;
364 } elsif ($s eq 'TTOU') {
365 if ($set_workers > 0) {
366 $worker_processes = --$set_workers;
368 } elsif ($s eq 'CHLD') {
373 my $n = scalar keys %pids;
374 if ($n > $worker_processes) {
375 while (my ($k, $v) = each %pids) {
376 kill('TERM', $k) if $v >= $worker_processes;
378 $n = $worker_processes;
380 foreach my $i ($n..($worker_processes - 1)) {
381 my ($pid, $err) = do_fork();
383 warn "failed to fork worker[$i]: $err\n";
384 } elsif ($pid == 0) {
385 $set_user->() if $set_user;
386 return $p0; # run normal work code
388 warn "PID=$pid is worker[$i]\n";
392 # just wait on signal events here:
393 sysread($r, my $buf, 8);
395 exit # never gets here, just for documentation
398 sub daemon_loop ($$) {
399 my ($refresh, $post_accept) = @_;
401 if ($worker_processes > 0) {
402 $refresh->(); # preload by default
403 $parent_pipe = master_loop(); # returns if in child process
404 my $fd = fileno($parent_pipe);
405 Danga::Socket->AddOtherFds($fd => *worker_quit);
408 $set_user->() if $set_user;
409 $SIG{USR2} = sub { worker_quit() if upgrade() };
414 $SIG{QUIT} = $SIG{INT} = $SIG{TERM} = *worker_quit;
415 $SIG{USR1} = *reopen_logs;
416 $SIG{HUP} = $refresh;
417 # this calls epoll_create:
419 PublicInbox::Listener->new($_, $post_accept)
421 Danga::Socket->EventLoop;
422 $parent_pipe = undef;
427 my ($default, $refresh, $post_accept) = @_;
428 daemon_prepare($default);
430 daemon_loop($refresh, $post_accept);
435 if (defined $uid and !chown($uid, $gid, $path)) {
436 warn "could not chown $path: $!\n";
442 Net::Server::Daemonize::create_pid_file($path);