| blob | ed5bbf1e4b5a7efc908f0a0a0d785ee5763cfd62 |
1 # -*- encoding: binary -*-
3 # This is the process manager of Unicorn. This manages worker
4 # processes which in turn handle the I/O and application process.
5 # Listener sockets are started in the master process and shared with
6 # forked worker children.
7 #
8 # Users do not need to know the internals of this class, but reading the
9 # {source}[https://yhbt.net/unicorn.git/tree/lib/unicorn/http_server.rb]
10 # is education for programmers wishing to learn how unicorn works.
11 # See Unicorn::Configurator for information on how to configure unicorn.
12 class Unicorn::HttpServer
13 # :stopdoc:
14 attr_accessor :app, :timeout, :worker_processes,
15 :before_fork, :after_fork, :before_exec,
16 :listener_opts, :preload_app,
17 :orig_app, :config, :ready_pipe, :user,
18 :default_middleware, :early_hints
19 attr_writer :after_worker_exit, :after_worker_ready, :worker_exec
21 attr_reader :pid, :logger
22 include Unicorn::SocketHelper
23 include Unicorn::HttpResponse
25 # all bound listener sockets
26 # note: this is public used by raindrops, but not recommended for use
27 # in new projects
28 LISTENERS = []
30 # listeners we have yet to bind
31 NEW_LISTENERS = []
33 # :startdoc:
34 # We populate this at startup so we can figure out how to reexecute
35 # and upgrade the currently running instance of Unicorn
36 # This Hash is considered a stable interface and changing its contents
37 # will allow you to switch between different installations of Unicorn
38 # or even different installations of the same applications without
39 # downtime. Keys of this constant Hash are described as follows:
40 #
41 # * 0 - the path to the unicorn executable
42 # * :argv - a deep copy of the ARGV array the executable originally saw
43 # * :cwd - the working directory of the application, this is where
44 # you originally started Unicorn.
45 #
46 # To change your unicorn executable to a different path without downtime,
47 # you can set the following in your Unicorn config file, HUP and then
48 # continue with the traditional USR2 + QUIT upgrade steps:
49 #
50 # Unicorn::HttpServer::START_CTX[0] = "/home/bofh/2.3.0/bin/unicorn"
51 START_CTX = {
52 :argv => ARGV.map(&:dup),
53 0 => $0.dup,
54 }
55 # We favor ENV['PWD'] since it is (usually) symlink aware for Capistrano
56 # and like systems
57 START_CTX[:cwd] = begin
58 a = File.stat(pwd = ENV['PWD'])
59 b = File.stat(Dir.pwd)
60 a.ino == b.ino && a.dev == b.dev ? pwd : Dir.pwd
61 rescue
62 Dir.pwd
63 end
64 # :stopdoc:
66 # Creates a working server on host:port (strange things happen if
67 # port isn't a Number). Use HttpServer::run to start the server and
68 # HttpServer.run.join to join the thread that's processing
69 # incoming requests on the socket.
70 def initialize(app, options = {})
71 @app = app
72 @reexec_pid = 0
73 @default_middleware = true
74 options = options.dup
75 @ready_pipe = options.delete(:ready_pipe)
76 @init_listeners = options[:listeners] ? options[:listeners].dup : []
77 options[:use_defaults] = true
78 self.config = Unicorn::Configurator.new(options)
79 self.listener_opts = {}
80 @immortal = [] # immortal inherited sockets from systemd
82 # We use @self_pipe differently in the master and worker processes:
83 #
84 # * The master process never closes or reinitializes this once
85 # initialized. Signal handlers in the master process will write to
86 # it to wake up the master from IO.select in exactly the same manner
87 # djb describes in https://cr.yp.to/docs/selfpipe.html
88 #
89 # * The workers immediately close the pipe they inherit. See the
90 # Unicorn::Worker class for the pipe workers use.
91 @self_pipe = []
92 @workers = {} # hash maps PIDs to Workers
93 @sig_queue = [] # signal queue used for self-piping
94 @pid = nil
96 # we try inheriting listeners first, so we bind them later.
97 # we don't write the pid file until we've bound listeners in case
98 # unicorn was started twice by mistake. Even though our #pid= method
99 # checks for stale/existing pid files, race conditions are still
100 # possible (and difficult/non-portable to avoid) and can be likely
101 # to clobber the pid if the second start was in quick succession
102 # after the first, so we rely on the listener binding to fail in
103 # that case. Some tests (in and outside of this source tree) and
104 # monitoring tools may also rely on pid files existing before we
105 # attempt to connect to the listener(s)
106 config.commit!(self, :skip => [:listeners, :pid])
107 @orig_app = app
108 # list of signals we care about and trap in master.
109 @queue_sigs = [
110 :WINCH, :QUIT, :INT, :TERM, :USR1, :USR2, :HUP, :TTIN, :TTOU ]
112 @worker_data = if worker_data = ENV['UNICORN_WORKER']
113 worker_data = worker_data.split(',').map!(&:to_i)
114 worker_data[1] = worker_data.slice!(1..2).map { |i| IO.for_fd(i) }
115 worker_data
116 end
117 end
119 # Runs the thing. Returns self so you can run join on it
120 def start
121 inherit_listeners!
122 # this pipe is used to wake us up from select(2) in #join when signals
123 # are trapped. See trap_deferred.
124 @self_pipe.replace(Unicorn.pipe)
125 @master_pid = @worker_data ? Process.ppid : $$
127 # setup signal handlers before writing pid file in case people get
128 # trigger happy and send signals as soon as the pid file exists.
129 # Note that signals don't actually get handled until the #join method
130 @queue_sigs.each { |sig| trap(sig) { @sig_queue << sig; awaken_master } }
131 trap(:CHLD) { awaken_master }
133 # write pid early for Mongrel compatibility if we're not inheriting sockets
134 # This is needed for compatibility some Monit setups at least.
135 # This unfortunately has the side effect of clobbering valid PID if
136 # we upgrade and the upgrade breaks during preload_app==true && build_app!
137 self.pid = config[:pid]
139 build_app! if preload_app
140 bind_new_listeners!
142 spawn_missing_workers
143 self
144 end
146 # replaces current listener set with +listeners+. This will
147 # close the socket if it will not exist in the new listener set
148 def listeners=(listeners)
149 cur_names, dead_names = [], []
150 listener_names.each do |name|
151 if name.start_with?('/')
152 # mark unlinked sockets as dead so we can rebind them
153 (File.socket?(name) ? cur_names : dead_names) << name
154 else
155 cur_names << name
156 end
157 end
158 set_names = listener_names(listeners)
159 dead_names.concat(cur_names - set_names).uniq!
160 dead_names -= @immortal.map { |io| sock_name(io) }
162 LISTENERS.delete_if do |io|
163 if dead_names.include?(sock_name(io))
164 (io.close rescue nil).nil? # true
165 else
166 set_server_sockopt(io, listener_opts[sock_name(io)])
167 false
168 end
169 end
171 (set_names - cur_names).each { |addr| listen(addr) }
172 end
174 def stdout_path=(path); redirect_io($stdout, path); end
175 def stderr_path=(path); redirect_io($stderr, path); end
177 def logger=(obj)
178 Unicorn::HttpRequest::DEFAULTS["rack.logger"] = @logger = obj
179 end
181 def clobber_pid(path)
182 unlink_pid_safe(@pid) if @pid
183 if path
184 fp = begin
185 tmp = "#{File.dirname(path)}/#{rand}.#$$"
186 File.open(tmp, File::RDWR|File::CREAT|File::EXCL, 0644)
187 rescue Errno::EEXIST
188 retry
189 end
190 fp.sync = true
191 fp.write("#$$\n")
192 File.rename(fp.path, path)
193 fp.close
194 end
195 end
197 # sets the path for the PID file of the master process
198 def pid=(path)
199 if path
200 if x = valid_pid?(path)
201 return path if pid && path == pid && x == $$
202 if x == @reexec_pid && pid.end_with?('.oldbin')
203 logger.warn("will not set pid=#{path} while reexec-ed "\
204 "child is running PID:#{x}")
205 return
206 end
207 raise ArgumentError, "Already running on PID:#{x} " \
208 "(or pid=#{path} is stale)"
209 end
210 end
212 # rename the old pid if possible
213 if @pid && path
214 begin
215 File.rename(@pid, path)
216 rescue Errno::ENOENT, Errno::EXDEV
217 # a user may have accidentally removed the original,
218 # obviously cross-FS renames don't work, either.
219 clobber_pid(path)
220 end
221 else
222 clobber_pid(path)
223 end
224 @pid = path
225 end
227 # add a given address to the +listeners+ set, idempotently
228 # Allows workers to add a private, per-process listener via the
229 # after_fork hook. Very useful for debugging and testing.
230 # +:tries+ may be specified as an option for the number of times
231 # to retry, and +:delay+ may be specified as the time in seconds
232 # to delay between retries.
233 # A negative value for +:tries+ indicates the listen will be
234 # retried indefinitely, this is useful when workers belonging to
235 # different masters are spawned during a transparent upgrade.
236 def listen(address, opt = {}.merge(listener_opts[address] || {}))
237 address = config.expand_addr(address)
238 return if String === address && listener_names.include?(address)
240 delay = opt[:delay] || 0.5
241 tries = opt[:tries] || 5
242 begin
243 io = bind_listen(address, opt)
244 logger.info "listening on addr=#{sock_name(io)} fd=#{io.fileno}"
245 LISTENERS << io
246 io
247 rescue Errno::EADDRINUSE => err
248 logger.error "adding listener failed addr=#{address} (in use)"
249 raise err if tries == 0
250 tries -= 1
251 logger.error "retrying in #{delay} seconds " \
252 "(#{tries < 0 ? 'infinite' : tries} tries left)"
253 sleep(delay)
254 retry
255 rescue => err
256 logger.fatal "error adding listener addr=#{address}"
257 raise err
258 end
259 end
261 # monitors children and receives signals forever
262 # (or until a termination signal is sent). This handles signals
263 # one-at-a-time time and we'll happily drop signals in case somebody
264 # is signalling us too often.
265 def join
266 respawn = true
267 last_check = time_now
269 proc_name 'master'
270 logger.info "master process ready" # test_exec.rb relies on this message
271 if @ready_pipe
272 begin
273 @ready_pipe.syswrite($$.to_s)
274 rescue => e
275 logger.warn("grandparent died too soon?: #{e.message} (#{e.class})")
276 end
277 @ready_pipe = @ready_pipe.close rescue nil
278 end
279 begin
280 reap_all_workers
281 case @sig_queue.shift
282 when nil
283 # avoid murdering workers after our master process (or the
284 # machine) comes out of suspend/hibernation
285 if (last_check + @timeout) >= (last_check = time_now)
286 sleep_time = murder_lazy_workers
287 else
288 sleep_time = @timeout/2.0 + 1
289 @logger.debug("waiting #{sleep_time}s after suspend/hibernation")
290 end
291 maintain_worker_count if respawn
292 master_sleep(sleep_time)
293 when :QUIT # graceful shutdown
294 break
295 when :TERM, :INT # immediate shutdown
296 stop(false)
297 break
298 when :USR1 # rotate logs
299 logger.info "master reopening logs..."
300 Unicorn::Util.reopen_logs
301 logger.info "master done reopening logs"
302 soft_kill_each_worker(:USR1)
303 when :USR2 # exec binary, stay alive in case something went wrong
304 reexec
305 when :WINCH
306 if $stdin.tty?
307 logger.info "SIGWINCH ignored because we're not daemonized"
308 else
309 respawn = false
310 logger.info "gracefully stopping all workers"
311 soft_kill_each_worker(:QUIT)
312 self.worker_processes = 0
313 end
314 when :TTIN
315 respawn = true
316 self.worker_processes += 1
317 when :TTOU
318 self.worker_processes -= 1 if self.worker_processes > 0
319 when :HUP
320 respawn = true
321 if config.config_file
322 load_config!
323 else # exec binary and exit if there's no config file
324 logger.info "config_file not present, reexecuting binary"
325 reexec
326 end
327 end
328 rescue => e
329 Unicorn.log_error(@logger, "master loop error", e)
330 end while true
331 stop # gracefully shutdown all workers on our way out
332 logger.info "master complete"
333 unlink_pid_safe(pid) if pid
334 end
336 # Terminates all workers, but does not exit master process
337 def stop(graceful = true)
338 self.listeners = []
339 limit = time_now + timeout
340 until @workers.empty? || time_now > limit
341 if graceful
342 soft_kill_each_worker(:QUIT)
343 else
344 kill_each_worker(:TERM)
345 end
346 sleep(0.1)
347 reap_all_workers
348 end
349 kill_each_worker(:KILL)
350 end
352 def rewindable_input
353 Unicorn::HttpRequest.input_class.method_defined?(:rewind)
354 end
356 def rewindable_input=(bool)
357 Unicorn::HttpRequest.input_class = bool ?
358 Unicorn::TeeInput : Unicorn::StreamInput
359 end
361 def client_body_buffer_size
362 Unicorn::TeeInput.client_body_buffer_size
363 end
365 def client_body_buffer_size=(bytes)
366 Unicorn::TeeInput.client_body_buffer_size = bytes
367 end
369 def check_client_connection
370 Unicorn::HttpRequest.check_client_connection
371 end
373 def check_client_connection=(bool)
374 Unicorn::HttpRequest.check_client_connection = bool
375 end
377 private
379 # wait for a signal hander to wake us up and then consume the pipe
380 def master_sleep(sec)
381 @self_pipe[0].wait(sec) or return
382 # 11 bytes is the maximum string length which can be embedded within
383 # the Ruby itself and not require a separate malloc (on 32-bit MRI 1.9+).
384 # Most reads are only one byte here and uncommon, so it's not worth a
385 # persistent buffer, either:
386 @self_pipe[0].read_nonblock(11, exception: false)
387 end
389 def awaken_master
390 return if $$ != @master_pid
391 # wakeup master process from select
392 @self_pipe[1].write_nonblock('.', exception: false)
393 end
395 # reaps all unreaped workers
396 def reap_all_workers
397 begin
398 wpid, status = Process.waitpid2(-1, Process::WNOHANG)
399 wpid or return
400 if @reexec_pid == wpid
401 logger.error "reaped #{status.inspect} exec()-ed"
402 @reexec_pid = 0
403 self.pid = pid.chomp('.oldbin') if pid
404 proc_name 'master'
405 else
406 worker = @workers.delete(wpid) and worker.close rescue nil
407 @after_worker_exit.call(self, worker, status)
408 end
409 rescue Errno::ECHILD
410 break
411 end while true
412 end
414 # reexecutes the START_CTX with a new binary
415 def reexec
416 if @reexec_pid > 0
417 begin
418 Process.kill(0, @reexec_pid)
419 logger.error "reexec-ed child already running PID:#@reexec_pid"
420 return
421 rescue Errno::ESRCH
422 @reexec_pid = 0
423 end
424 end
426 if pid
427 old_pid = "#{pid}.oldbin"
428 begin
429 self.pid = old_pid # clear the path for a new pid file
430 rescue ArgumentError
431 logger.error "old PID:#{valid_pid?(old_pid)} running with " \
432 "existing pid=#{old_pid}, refusing rexec"
433 return
434 rescue => e
435 logger.error "error writing pid=#{old_pid} #{e.class} #{e.message}"
436 return
437 end
438 end
440 @reexec_pid = fork do
441 listener_fds = listener_sockets
442 ENV['UNICORN_FD'] = listener_fds.keys.join(',')
443 Dir.chdir(START_CTX[:cwd])
444 cmd = [ START_CTX[0] ].concat(START_CTX[:argv])
446 # exec(command, hash) works in at least 1.9.1+, but will only be
447 # required in 1.9.4/2.0.0 at earliest.
448 cmd << listener_fds
449 logger.info "executing #{cmd.inspect} (in #{Dir.pwd})"
450 before_exec.call(self)
451 exec(*cmd)
452 end
453 proc_name 'master (old)'
454 end
456 def worker_spawn(worker)
457 listener_fds = listener_sockets
458 env = {}
459 env['UNICORN_FD'] = listener_fds.keys.join(',')
461 listener_fds[worker.to_io.fileno] = worker.to_io
462 listener_fds[worker.master.fileno] = worker.master
464 worker_info = [worker.nr, worker.to_io.fileno, worker.master.fileno]
465 env['UNICORN_WORKER'] = worker_info.join(',')
467 Process.spawn(env, START_CTX[0], *START_CTX[:argv], listener_fds)
468 end
470 def listener_sockets
471 listener_fds = {}
472 LISTENERS.each { |sock| listener_fds[sock.fileno] = sock }
473 listener_fds
474 end
476 # forcibly terminate all workers that haven't checked in in timeout seconds. The timeout is implemented using an unlinked File
477 def murder_lazy_workers
478 next_sleep = @timeout - 1
479 now = time_now.to_i
480 @workers.dup.each_pair do |wpid, worker|
481 tick = worker.tick
482 0 == tick and next # skip workers that haven't processed any clients
483 diff = now - tick
484 tmp = @timeout - diff
485 if tmp >= 0
486 next_sleep > tmp and next_sleep = tmp
487 next
488 end
489 next_sleep = 0
490 logger.error "worker=#{worker.nr} PID:#{wpid} timeout " \
491 "(#{diff}s > #{@timeout}s), killing"
492 kill_worker(:KILL, wpid) # take no prisoners for timeout violations
493 end
494 next_sleep <= 0 ? 1 : next_sleep
495 end
497 def after_fork_internal
498 @self_pipe.each(&:close).clear # this is master-only, now
499 @ready_pipe.close if @ready_pipe
500 Unicorn::Configurator::RACKUP.clear
501 @ready_pipe = @init_listeners = @before_exec = @before_fork = nil
503 # The OpenSSL PRNG is seeded with only the pid, and apps with frequently
504 # dying workers can recycle pids
505 OpenSSL::Random.seed(rand.to_s) if defined?(OpenSSL::Random)
506 end
508 def spawn_missing_workers
509 if @worker_data
510 worker = Unicorn::Worker.new(*@worker_data)
511 after_fork_internal
512 worker_loop(worker)
513 exit
514 end
516 worker_nr = -1
517 until (worker_nr += 1) == @worker_processes
518 @workers.value?(worker_nr) and next
519 worker = Unicorn::Worker.new(worker_nr)
520 before_fork.call(self, worker)
522 pid = @worker_exec ? worker_spawn(worker) : fork
524 unless pid
525 after_fork_internal
526 worker_loop(worker)
527 exit
528 end
530 @workers[pid] = worker
531 worker.atfork_parent
532 end
533 rescue => e
534 @logger.error(e) rescue nil
535 exit!
536 end
538 def maintain_worker_count
539 (off = @workers.size - worker_processes) == 0 and return
540 off < 0 and return spawn_missing_workers
541 @workers.each_value { |w| w.nr >= worker_processes and w.soft_kill(:QUIT) }
542 end
544 # if we get any error, try to write something back to the client
545 # assuming we haven't closed the socket, but don't get hung up
546 # if the socket is already closed or broken. We'll always ensure
547 # the socket is closed at the end of this function
548 def handle_error(client, e)
549 code = case e
550 when EOFError,Errno::ECONNRESET,Errno::EPIPE,Errno::ENOTCONN
551 # client disconnected on us and there's nothing we can do
552 when Unicorn::RequestURITooLongError
553 414
554 when Unicorn::RequestEntityTooLargeError
555 413
556 when Unicorn::HttpParserError # try to tell the client they're bad
557 400
558 else
559 Unicorn.log_error(@logger, "app error", e)
560 500
561 end
562 if code
563 code = err_response(code, @request.response_start_sent)
564 client.write_nonblock(code, exception: false)
565 end
566 client.close
567 rescue
568 end
570 def e103_response_write(client, headers)
571 rss = @request.response_start_sent
572 buf = rss ? "103 Early Hints\r\n" : "HTTP/1.1 103 Early Hints\r\n"
573 headers.each { |key, value| append_header(buf, key, value) }
574 buf << (rss ? "\r\nHTTP/1.1 ".freeze : "\r\n".freeze)
575 client.write(buf)
576 end
578 def e100_response_write(client, env)
579 # We use String#freeze to avoid allocations under Ruby 2.1+
580 # Not many users hit this code path, so it's better to reduce the
581 # constant table sizes even for Ruby 2.0 users who'll hit extra
582 # allocations here.
583 client.write(@request.response_start_sent ?
584 "100 Continue\r\n\r\nHTTP/1.1 ".freeze :
585 "HTTP/1.1 100 Continue\r\n\r\n".freeze)
586 env.delete('HTTP_EXPECT'.freeze)
587 end
589 # once a client is accepted, it is processed in its entirety here
590 # in 3 easy steps: read request, call app, write app response
591 def process_client(client, ai)
592 @request = Unicorn::HttpRequest.new
593 env = @request.read_headers(client, ai)
595 if early_hints
596 env["rack.early_hints"] = lambda do |headers|
597 e103_response_write(client, headers)
598 end
599 end
601 env["rack.after_reply"] = []
603 status, headers, body = @app.call(env)
605 begin
606 return if @request.hijacked?
608 if 100 == status.to_i
609 e100_response_write(client, env)
610 status, headers, body = @app.call(env)
611 return if @request.hijacked?
612 end
613 @request.headers? or headers = nil
614 http_response_write(client, status, headers, body, @request)
615 ensure
616 body.respond_to?(:close) and body.close
617 end
619 unless client.closed? # rack.hijack may've close this for us
620 client.shutdown # in case of fork() in Rack app
621 client.close # flush and uncork socket immediately, no keepalive
622 end
623 rescue => e
624 handle_error(client, e)
625 ensure
626 env["rack.after_reply"].each(&:call) if env
627 end
629 def nuke_listeners!(readers)
630 # only called from the worker, ordering is important here
631 tmp = readers.dup
632 readers.replace([false]) # ensure worker does not continue ASAP
633 tmp.each { |io| io.close rescue nil } # break out of IO.select
634 end
636 # gets rid of stuff the worker has no business keeping track of
637 # to free some resources and drops all sig handlers.
638 # traps for USR1, USR2, and HUP may be set in the after_fork Proc
639 # by the user.
640 def init_worker_process(worker)
641 worker.atfork_child
642 # we'll re-trap :QUIT later for graceful shutdown iff we accept clients
643 exit_sigs = [ :QUIT, :TERM, :INT ]
644 exit_sigs.each { |sig| trap(sig) { exit!(0) } }
645 exit!(0) if (@sig_queue & exit_sigs)[0]
646 (@queue_sigs - exit_sigs).each { |sig| trap(sig, nil) }
647 trap(:CHLD, 'DEFAULT')
648 @sig_queue.clear
649 proc_name "worker[#{worker.nr}]"
650 START_CTX.clear
651 @workers.clear
653 after_fork.call(self, worker) # can drop perms and create listeners
654 LISTENERS.each { |sock| sock.close_on_exec = true }
656 worker.user(*user) if user.kind_of?(Array) && ! worker.switched
657 @config = nil
658 build_app! unless preload_app
659 @after_fork = @listener_opts = @orig_app = nil
660 readers = LISTENERS.dup
661 readers << worker
662 trap(:QUIT) { nuke_listeners!(readers) }
663 readers
664 end
666 def reopen_worker_logs(worker_nr)
667 logger.info "worker=#{worker_nr} reopening logs..."
668 Unicorn::Util.reopen_logs
669 logger.info "worker=#{worker_nr} done reopening logs"
670 false
671 rescue => e
672 logger.error(e) rescue nil
673 exit!(77) # EX_NOPERM in sysexits.h
674 end
676 def prep_readers(readers)
677 wtr = Unicorn::Waiter.prep_readers(readers)
678 @timeout *= 500 # to milliseconds for epoll, but halved
679 wtr
680 rescue
681 require_relative 'select_waiter'
682 @timeout /= 2.0 # halved for IO.select
683 Unicorn::SelectWaiter.new
684 end
686 # runs inside each forked worker, this sits around and waits
687 # for connections and doesn't die until the parent dies (or is
688 # given a INT, QUIT, or TERM signal)
689 def worker_loop(worker)
690 readers = init_worker_process(worker)
691 waiter = prep_readers(readers)
692 reopen = false
694 # this only works immediately if the master sent us the signal
695 # (which is the normal case)
696 trap(:USR1) { reopen = true }
698 ready = readers.dup
699 @after_worker_ready.call(self, worker)
701 begin
702 reopen = reopen_worker_logs(worker.nr) if reopen
703 worker.tick = time_now.to_i
704 while sock = ready.shift
705 client_ai = sock.accept_nonblock(exception: false)
706 if client_ai != :wait_readable
707 process_client(*client_ai)
708 worker.tick = time_now.to_i
709 end
710 break if reopen
711 end
713 # timeout so we can .tick and keep parent from SIGKILL-ing us
714 worker.tick = time_now.to_i
715 waiter.get_readers(ready, readers, @timeout)
716 rescue => e
717 redo if reopen && readers[0]
718 Unicorn.log_error(@logger, "listen loop error", e) if readers[0]
719 end while readers[0]
720 end
722 # delivers a signal to a worker and fails gracefully if the worker
723 # is no longer running.
724 def kill_worker(signal, wpid)
725 Process.kill(signal, wpid)
726 rescue Errno::ESRCH
727 worker = @workers.delete(wpid) and worker.close rescue nil
728 end
730 # delivers a signal to each worker
731 def kill_each_worker(signal)
732 @workers.keys.each { |wpid| kill_worker(signal, wpid) }
733 end
735 def soft_kill_each_worker(signal)
736 @workers.each_value { |worker| worker.soft_kill(signal) }
737 end
739 # unlinks a PID file at given +path+ if it contains the current PID
740 # still potentially racy without locking the directory (which is
741 # non-portable and may interact badly with other programs), but the
742 # window for hitting the race condition is small
743 def unlink_pid_safe(path)
744 (File.read(path).to_i == $$ and File.unlink(path)) rescue nil
745 end
747 # returns a PID if a given path contains a non-stale PID file,
748 # nil otherwise.
749 def valid_pid?(path)
750 wpid = File.read(path).to_i
751 wpid <= 0 and return
752 Process.kill(0, wpid)
753 wpid
754 rescue Errno::EPERM
755 logger.info "pid=#{path} possibly stale, got EPERM signalling PID:#{wpid}"
756 nil
757 rescue Errno::ESRCH, Errno::ENOENT
758 # don't unlink stale pid files, racy without non-portable locking...
759 end
761 def load_config!
762 loaded_app = app
763 logger.info "reloading config_file=#{config.config_file}"
764 config[:listeners].replace(@init_listeners)
765 config.reload
766 config.commit!(self)
767 soft_kill_each_worker(:QUIT)
768 Unicorn::Util.reopen_logs
769 self.app = @orig_app
770 build_app! if preload_app
771 logger.info "done reloading config_file=#{config.config_file}"
772 rescue StandardError, LoadError, SyntaxError => e
773 Unicorn.log_error(@logger,
774 "error reloading config_file=#{config.config_file}", e)
775 self.app = loaded_app
776 end
778 # returns an array of string names for the given listener array
779 def listener_names(listeners = LISTENERS)
780 listeners.map { |io| sock_name(io) }
781 end
783 def build_app!
784 if app.respond_to?(:arity) && (app.arity == 0 || app.arity == 2)
785 if defined?(Gem) && Gem.respond_to?(:refresh)
786 logger.info "Refreshing Gem list"
787 Gem.refresh
788 end
789 self.app = app.arity == 0 ? app.call : app.call(nil, self)
790 end
791 end
793 def proc_name(tag)
794 $0 = ([ File.basename(START_CTX[0]), tag
795 ]).concat(START_CTX[:argv]).join(' ')
796 end
798 def redirect_io(io, path)
799 File.open(path, 'ab') { |fp| io.reopen(fp) } if path
800 io.sync = true
801 end
803 def inherit_listeners!
804 # inherit sockets from parents, they need to be plain Socket objects
805 inherited = ENV['UNICORN_FD'].to_s.split(',')
806 immortal = []
808 # emulate sd_listen_fds() for systemd
809 sd_pid, sd_fds = ENV.values_at('LISTEN_PID', 'LISTEN_FDS')
810 if sd_pid.to_i == $$ # n.b. $$ can never be zero
811 # 3 = SD_LISTEN_FDS_START
812 immortal = (3...(3 + sd_fds.to_i)).to_a
813 inherited.concat(immortal)
814 end
815 # to ease debugging, we will not unset LISTEN_PID and LISTEN_FDS
817 inherited.map! do |fd|
818 io = Socket.for_fd(fd.to_i)
819 @immortal << io if immortal.include?(fd)
820 set_server_sockopt(io, listener_opts[sock_name(io)])
821 logger.info "inherited addr=#{sock_name(io)} fd=#{io.fileno}"
822 io
823 end
825 config_listeners = config[:listeners].dup
826 LISTENERS.replace(inherited)
828 # we only use generic Socket objects for aggregate Socket#accept_nonblock
829 # return value [ Socket, Addrinfo ]. This allows us to avoid having to
830 # make getpeername(2) syscalls later on to fill in env['REMOTE_ADDR']
831 config_listeners -= listener_names
832 if config_listeners.empty? && LISTENERS.empty?
833 config_listeners << Unicorn::Const::DEFAULT_LISTEN
834 @init_listeners << Unicorn::Const::DEFAULT_LISTEN
835 START_CTX[:argv] << "-l#{Unicorn::Const::DEFAULT_LISTEN}"
836 end
837 NEW_LISTENERS.replace(config_listeners)
838 end
840 # call only after calling inherit_listeners!
841 # This binds any listeners we did NOT inherit from the parent
842 def bind_new_listeners!
843 NEW_LISTENERS.each { |addr| listen(addr) }.clear
844 raise ArgumentError, "no listeners" if LISTENERS.empty?
845 end
847 # try to use the monotonic clock in Ruby >= 2.1, it is immune to clock
848 # offset adjustments and generates less garbage (Float vs Time object)
849 begin
850 Process.clock_gettime(Process::CLOCK_MONOTONIC)
851 def time_now
852 Process.clock_gettime(Process::CLOCK_MONOTONIC)
853 end
854 rescue NameError, NoMethodError
855 def time_now # Ruby <= 2.0
856 Time.now
857 end
858 end
859 end