| blob | 08fbe4065f1ae11e3fb20e7f663b829dad7f491b |
1 # -*- encoding: binary -*-
2 # frozen_string_literal: false
4 # This is the process manager of Unicorn. This manages worker
5 # processes which in turn handle the I/O and application process.
6 # Listener sockets are started in the master process and shared with
7 # forked worker children.
8 #
9 # Users do not need to know the internals of this class, but reading the
10 # {source}[https://yhbt.net/unicorn.git/tree/lib/unicorn/http_server.rb]
11 # is education for programmers wishing to learn how unicorn works.
12 # See Unicorn::Configurator for information on how to configure unicorn.
13 class Unicorn::HttpServer
14 # :stopdoc:
15 attr_accessor :app, :timeout, :worker_processes,
16 :before_fork, :after_fork, :before_exec,
17 :listener_opts, :preload_app,
18 :orig_app, :config, :ready_pipe, :user,
19 :default_middleware, :early_hints
20 attr_writer :after_worker_exit, :after_worker_ready, :worker_exec
22 attr_reader :pid, :logger
23 include Unicorn::SocketHelper
24 include Unicorn::HttpResponse
26 # all bound listener sockets
27 # note: this is public used by raindrops, but not recommended for use
28 # in new projects
29 LISTENERS = []
31 # listeners we have yet to bind
32 NEW_LISTENERS = []
34 # :startdoc:
35 # We populate this at startup so we can figure out how to reexecute
36 # and upgrade the currently running instance of Unicorn
37 # This Hash is considered a stable interface and changing its contents
38 # will allow you to switch between different installations of Unicorn
39 # or even different installations of the same applications without
40 # downtime. Keys of this constant Hash are described as follows:
41 #
42 # * 0 - the path to the unicorn executable
43 # * :argv - a deep copy of the ARGV array the executable originally saw
44 # * :cwd - the working directory of the application, this is where
45 # you originally started Unicorn.
46 #
47 # To change your unicorn executable to a different path without downtime,
48 # you can set the following in your Unicorn config file, HUP and then
49 # continue with the traditional USR2 + QUIT upgrade steps:
50 #
51 # Unicorn::HttpServer::START_CTX[0] = "/home/bofh/2.3.0/bin/unicorn"
52 START_CTX = {
53 :argv => ARGV.map(&:dup),
54 0 => $0.dup,
55 }
56 # We favor ENV['PWD'] since it is (usually) symlink aware for Capistrano
57 # and like systems
58 START_CTX[:cwd] = begin
59 a = File.stat(pwd = ENV['PWD'])
60 b = File.stat(Dir.pwd)
61 a.ino == b.ino && a.dev == b.dev ? pwd : Dir.pwd
62 rescue
63 Dir.pwd
64 end
65 # :stopdoc:
67 # Creates a working server on host:port (strange things happen if
68 # port isn't a Number). Use HttpServer::run to start the server and
69 # HttpServer.run.join to join the thread that's processing
70 # incoming requests on the socket.
71 def initialize(app, options = {})
72 @app = app
73 @reexec_pid = 0
74 @default_middleware = true
75 options = options.dup
76 @ready_pipe = options.delete(:ready_pipe)
77 @init_listeners = options[:listeners] ? options[:listeners].dup : []
78 options[:use_defaults] = true
79 self.config = Unicorn::Configurator.new(options)
80 self.listener_opts = {}
81 @immortal = [] # immortal inherited sockets from systemd
83 # We use @self_pipe differently in the master and worker processes:
84 #
85 # * The master process never closes or reinitializes this once
86 # initialized. Signal handlers in the master process will write to
87 # it to wake up the master from IO.select in exactly the same manner
88 # djb describes in https://cr.yp.to/docs/selfpipe.html
89 #
90 # * The workers immediately close the pipe they inherit. See the
91 # Unicorn::Worker class for the pipe workers use.
92 @self_pipe = []
93 @workers = {} # hash maps PIDs to Workers
94 @sig_queue = [] # signal queue used for self-piping
95 @pid = nil
97 # we try inheriting listeners first, so we bind them later.
98 # we don't write the pid file until we've bound listeners in case
99 # unicorn was started twice by mistake. Even though our #pid= method
100 # checks for stale/existing pid files, race conditions are still
101 # possible (and difficult/non-portable to avoid) and can be likely
102 # to clobber the pid if the second start was in quick succession
103 # after the first, so we rely on the listener binding to fail in
104 # that case. Some tests (in and outside of this source tree) and
105 # monitoring tools may also rely on pid files existing before we
106 # attempt to connect to the listener(s)
107 config.commit!(self, :skip => [:listeners, :pid])
108 @orig_app = app
109 # list of signals we care about and trap in master.
110 @queue_sigs = [
111 :WINCH, :QUIT, :INT, :TERM, :USR1, :USR2, :HUP, :TTIN, :TTOU ]
113 @worker_data = if worker_data = ENV['UNICORN_WORKER']
114 worker_data = worker_data.split(',').map!(&:to_i)
115 worker_data[1] = worker_data.slice!(1..2).map { |i| IO.for_fd(i) }
116 worker_data
117 end
118 end
120 # Runs the thing. Returns self so you can run join on it
121 def start
122 inherit_listeners!
123 # this pipe is used to wake us up from select(2) in #join when signals
124 # are trapped. See trap_deferred.
125 @self_pipe.replace(Unicorn.pipe)
126 @master_pid = @worker_data ? Process.ppid : $$
128 # setup signal handlers before writing pid file in case people get
129 # trigger happy and send signals as soon as the pid file exists.
130 # Note that signals don't actually get handled until the #join method
131 @queue_sigs.each { |sig| trap(sig) { @sig_queue << sig; awaken_master } }
132 trap(:CHLD) { awaken_master }
134 # write pid early for Mongrel compatibility if we're not inheriting sockets
135 # This is needed for compatibility some Monit setups at least.
136 # This unfortunately has the side effect of clobbering valid PID if
137 # we upgrade and the upgrade breaks during preload_app==true && build_app!
138 self.pid = config[:pid]
140 build_app! if preload_app
141 bind_new_listeners!
143 spawn_missing_workers
144 self
145 end
147 # replaces current listener set with +listeners+. This will
148 # close the socket if it will not exist in the new listener set
149 def listeners=(listeners)
150 cur_names, dead_names = [], []
151 listener_names.each do |name|
152 if name.start_with?('/')
153 # mark unlinked sockets as dead so we can rebind them
154 (File.socket?(name) ? cur_names : dead_names) << name
155 else
156 cur_names << name
157 end
158 end
159 set_names = listener_names(listeners)
160 dead_names.concat(cur_names - set_names).uniq!
161 dead_names -= @immortal.map { |io| sock_name(io) }
163 LISTENERS.delete_if do |io|
164 if dead_names.include?(sock_name(io))
165 (io.close rescue nil).nil? # true
166 else
167 set_server_sockopt(io, listener_opts[sock_name(io)])
168 false
169 end
170 end
172 (set_names - cur_names).each { |addr| listen(addr) }
173 end
175 def stdout_path=(path); redirect_io($stdout, path); end
176 def stderr_path=(path); redirect_io($stderr, path); end
178 def logger=(obj)
179 Unicorn::HttpRequest::DEFAULTS["rack.logger"] = @logger = obj
180 end
182 def clobber_pid(path)
183 unlink_pid_safe(@pid) if @pid
184 if path
185 fp = begin
186 tmp = "#{File.dirname(path)}/#{rand}.#$$"
187 File.open(tmp, File::RDWR|File::CREAT|File::EXCL, 0644)
188 rescue Errno::EEXIST
189 retry
190 end
191 fp.sync = true
192 fp.write("#$$\n")
193 File.rename(fp.path, path)
194 fp.close
195 end
196 end
198 # sets the path for the PID file of the master process
199 def pid=(path)
200 if path
201 if x = valid_pid?(path)
202 return path if pid && path == pid && x == $$
203 if x == @reexec_pid && pid.end_with?('.oldbin')
204 logger.warn("will not set pid=#{path} while reexec-ed "\
205 "child is running PID:#{x}")
206 return
207 end
208 raise ArgumentError, "Already running on PID:#{x} " \
209 "(or pid=#{path} is stale)"
210 end
211 end
213 # rename the old pid if possible
214 if @pid && path
215 begin
216 File.rename(@pid, path)
217 rescue Errno::ENOENT, Errno::EXDEV
218 # a user may have accidentally removed the original,
219 # obviously cross-FS renames don't work, either.
220 clobber_pid(path)
221 end
222 else
223 clobber_pid(path)
224 end
225 @pid = path
226 end
228 # add a given address to the +listeners+ set, idempotently
229 # Allows workers to add a private, per-process listener via the
230 # after_fork hook. Very useful for debugging and testing.
231 # +:tries+ may be specified as an option for the number of times
232 # to retry, and +:delay+ may be specified as the time in seconds
233 # to delay between retries.
234 # A negative value for +:tries+ indicates the listen will be
235 # retried indefinitely, this is useful when workers belonging to
236 # different masters are spawned during a transparent upgrade.
237 def listen(address, opt = {}.merge(listener_opts[address] || {}))
238 address = config.expand_addr(address)
239 return if String === address && listener_names.include?(address)
241 delay = opt[:delay] || 0.5
242 tries = opt[:tries] || 5
243 begin
244 io = bind_listen(address, opt)
245 logger.info "listening on addr=#{sock_name(io)} fd=#{io.fileno}"
246 LISTENERS << io
247 io
248 rescue Errno::EADDRINUSE => err
249 logger.error "adding listener failed addr=#{address} (in use)"
250 raise err if tries == 0
251 tries -= 1
252 logger.error "retrying in #{delay} seconds " \
253 "(#{tries < 0 ? 'infinite' : tries} tries left)"
254 sleep(delay)
255 retry
256 rescue => err
257 logger.fatal "error adding listener addr=#{address}"
258 raise err
259 end
260 end
262 # monitors children and receives signals forever
263 # (or until a termination signal is sent). This handles signals
264 # one-at-a-time time and we'll happily drop signals in case somebody
265 # is signalling us too often.
266 def join
267 respawn = true
268 last_check = time_now
270 proc_name 'master'
271 logger.info "master process ready" # test_exec.rb relies on this message
272 if @ready_pipe
273 begin
274 @ready_pipe.syswrite($$.to_s)
275 rescue => e
276 logger.warn("grandparent died too soon?: #{e.message} (#{e.class})")
277 end
278 @ready_pipe = @ready_pipe.close rescue nil
279 end
280 begin
281 reap_all_workers
282 case @sig_queue.shift
283 when nil
284 # avoid murdering workers after our master process (or the
285 # machine) comes out of suspend/hibernation
286 if (last_check + @timeout) >= (last_check = time_now)
287 sleep_time = murder_lazy_workers
288 else
289 sleep_time = @timeout/2.0 + 1
290 @logger.debug("waiting #{sleep_time}s after suspend/hibernation")
291 end
292 maintain_worker_count if respawn
293 master_sleep(sleep_time)
294 when :QUIT # graceful shutdown
295 break
296 when :TERM, :INT # immediate shutdown
297 stop(false)
298 break
299 when :USR1 # rotate logs
300 logger.info "master reopening logs..."
301 Unicorn::Util.reopen_logs
302 logger.info "master done reopening logs"
303 soft_kill_each_worker(:USR1)
304 when :USR2 # exec binary, stay alive in case something went wrong
305 reexec
306 when :WINCH
307 if $stdin.tty?
308 logger.info "SIGWINCH ignored because we're not daemonized"
309 else
310 respawn = false
311 logger.info "gracefully stopping all workers"
312 soft_kill_each_worker(:QUIT)
313 self.worker_processes = 0
314 end
315 when :TTIN
316 respawn = true
317 self.worker_processes += 1
318 when :TTOU
319 self.worker_processes -= 1 if self.worker_processes > 0
320 when :HUP
321 respawn = true
322 if config.config_file
323 load_config!
324 else # exec binary and exit if there's no config file
325 logger.info "config_file not present, reexecuting binary"
326 reexec
327 end
328 end
329 rescue => e
330 Unicorn.log_error(@logger, "master loop error", e)
331 end while true
332 stop # gracefully shutdown all workers on our way out
333 logger.info "master complete"
334 unlink_pid_safe(pid) if pid
335 end
337 # Terminates all workers, but does not exit master process
338 def stop(graceful = true)
339 self.listeners = []
340 limit = time_now + timeout
341 until @workers.empty? || time_now > limit
342 if graceful
343 soft_kill_each_worker(:QUIT)
344 else
345 kill_each_worker(:TERM)
346 end
347 sleep(0.1)
348 reap_all_workers
349 end
350 kill_each_worker(:KILL)
351 end
353 def rewindable_input
354 Unicorn::HttpRequest.input_class.method_defined?(:rewind)
355 end
357 def rewindable_input=(bool)
358 Unicorn::HttpRequest.input_class = bool ?
359 Unicorn::TeeInput : Unicorn::StreamInput
360 end
362 def client_body_buffer_size
363 Unicorn::TeeInput.client_body_buffer_size
364 end
366 def client_body_buffer_size=(bytes)
367 Unicorn::TeeInput.client_body_buffer_size = bytes
368 end
370 def check_client_connection
371 Unicorn::HttpRequest.check_client_connection
372 end
374 def check_client_connection=(bool)
375 Unicorn::HttpRequest.check_client_connection = bool
376 end
378 private
380 # wait for a signal hander to wake us up and then consume the pipe
381 def master_sleep(sec)
382 @self_pipe[0].wait(sec) or return
383 # 11 bytes is the maximum string length which can be embedded within
384 # the Ruby itself and not require a separate malloc (on 32-bit MRI 1.9+).
385 # Most reads are only one byte here and uncommon, so it's not worth a
386 # persistent buffer, either:
387 @self_pipe[0].read_nonblock(11, exception: false)
388 end
390 def awaken_master
391 return if $$ != @master_pid
392 # wakeup master process from select
393 @self_pipe[1].write_nonblock('.', exception: false)
394 end
396 # reaps all unreaped workers
397 def reap_all_workers
398 begin
399 wpid, status = Process.waitpid2(-1, Process::WNOHANG)
400 wpid or return
401 if @reexec_pid == wpid
402 logger.error "reaped #{status.inspect} exec()-ed"
403 @reexec_pid = 0
404 self.pid = pid.chomp('.oldbin') if pid
405 proc_name 'master'
406 else
407 worker = @workers.delete(wpid) and worker.close rescue nil
408 @after_worker_exit.call(self, worker, status)
409 end
410 rescue Errno::ECHILD
411 break
412 end while true
413 end
415 # reexecutes the START_CTX with a new binary
416 def reexec
417 if @reexec_pid > 0
418 begin
419 Process.kill(0, @reexec_pid)
420 logger.error "reexec-ed child already running PID:#@reexec_pid"
421 return
422 rescue Errno::ESRCH
423 @reexec_pid = 0
424 end
425 end
427 if pid
428 old_pid = "#{pid}.oldbin"
429 begin
430 self.pid = old_pid # clear the path for a new pid file
431 rescue ArgumentError
432 logger.error "old PID:#{valid_pid?(old_pid)} running with " \
433 "existing pid=#{old_pid}, refusing rexec"
434 return
435 rescue => e
436 logger.error "error writing pid=#{old_pid} #{e.class} #{e.message}"
437 return
438 end
439 end
441 @reexec_pid = fork do
442 listener_fds = listener_sockets
443 ENV['UNICORN_FD'] = listener_fds.keys.join(',')
444 Dir.chdir(START_CTX[:cwd])
445 cmd = [ START_CTX[0] ].concat(START_CTX[:argv])
447 # exec(command, hash) works in at least 1.9.1+, but will only be
448 # required in 1.9.4/2.0.0 at earliest.
449 cmd << listener_fds
450 logger.info "executing #{cmd.inspect} (in #{Dir.pwd})"
451 before_exec.call(self)
452 exec(*cmd)
453 end
454 proc_name 'master (old)'
455 end
457 def worker_spawn(worker)
458 listener_fds = listener_sockets
459 env = {}
460 env['UNICORN_FD'] = listener_fds.keys.join(',')
462 listener_fds[worker.to_io.fileno] = worker.to_io
463 listener_fds[worker.master.fileno] = worker.master
465 worker_info = [worker.nr, worker.to_io.fileno, worker.master.fileno]
466 env['UNICORN_WORKER'] = worker_info.join(',')
468 Process.spawn(env, START_CTX[0], *START_CTX[:argv], listener_fds)
469 end
471 def listener_sockets
472 listener_fds = {}
473 LISTENERS.each { |sock| listener_fds[sock.fileno] = sock }
474 listener_fds
475 end
477 # forcibly terminate all workers that haven't checked in in timeout seconds. The timeout is implemented using an unlinked File
478 def murder_lazy_workers
479 next_sleep = @timeout - 1
480 now = time_now.to_i
481 @workers.dup.each_pair do |wpid, worker|
482 tick = worker.tick
483 0 == tick and next # skip workers that haven't processed any clients
484 diff = now - tick
485 tmp = @timeout - diff
486 if tmp >= 0
487 next_sleep > tmp and next_sleep = tmp
488 next
489 end
490 next_sleep = 0
491 logger.error "worker=#{worker.nr} PID:#{wpid} timeout " \
492 "(#{diff}s > #{@timeout}s), killing"
493 kill_worker(:KILL, wpid) # take no prisoners for timeout violations
494 end
495 next_sleep <= 0 ? 1 : next_sleep
496 end
498 def after_fork_internal
499 @self_pipe.each(&:close).clear # this is master-only, now
500 @ready_pipe.close if @ready_pipe
501 Unicorn::Configurator::RACKUP.clear
502 @ready_pipe = @init_listeners = @before_exec = @before_fork = nil
504 # The OpenSSL PRNG is seeded with only the pid, and apps with frequently
505 # dying workers can recycle pids
506 OpenSSL::Random.seed(rand.to_s) if defined?(OpenSSL::Random)
507 end
509 def spawn_missing_workers
510 if @worker_data
511 worker = Unicorn::Worker.new(*@worker_data)
512 after_fork_internal
513 worker_loop(worker)
514 exit
515 end
517 worker_nr = -1
518 until (worker_nr += 1) == @worker_processes
519 @workers.value?(worker_nr) and next
520 worker = Unicorn::Worker.new(worker_nr)
521 before_fork.call(self, worker)
523 pid = @worker_exec ? worker_spawn(worker) : fork
525 unless pid
526 after_fork_internal
527 worker_loop(worker)
528 exit
529 end
531 @workers[pid] = worker
532 worker.atfork_parent
533 end
534 rescue => e
535 @logger.error(e) rescue nil
536 exit!
537 end
539 def maintain_worker_count
540 (off = @workers.size - worker_processes) == 0 and return
541 off < 0 and return spawn_missing_workers
542 @workers.each_value { |w| w.nr >= worker_processes and w.soft_kill(:QUIT) }
543 end
545 # if we get any error, try to write something back to the client
546 # assuming we haven't closed the socket, but don't get hung up
547 # if the socket is already closed or broken. We'll always ensure
548 # the socket is closed at the end of this function
549 def handle_error(client, e)
550 code = case e
551 when EOFError,Errno::ECONNRESET,Errno::EPIPE,Errno::ENOTCONN
552 # client disconnected on us and there's nothing we can do
553 when Unicorn::RequestURITooLongError
554 414
555 when Unicorn::RequestEntityTooLargeError
556 413
557 when Unicorn::HttpParserError # try to tell the client they're bad
558 400
559 else
560 Unicorn.log_error(@logger, "app error", e)
561 500
562 end
563 if code
564 code = err_response(code, @request.response_start_sent)
565 client.write_nonblock(code, exception: false)
566 end
567 client.close
568 rescue
569 end
571 def e103_response_write(client, headers)
572 rss = @request.response_start_sent
573 buf = rss ? "103 Early Hints\r\n" : "HTTP/1.1 103 Early Hints\r\n"
574 headers.each { |key, value| append_header(buf, key, value) }
575 buf << (rss ? "\r\nHTTP/1.1 ".freeze : "\r\n".freeze)
576 client.write(buf)
577 end
579 def e100_response_write(client, env)
580 # We use String#freeze to avoid allocations under Ruby 2.1+
581 # Not many users hit this code path, so it's better to reduce the
582 # constant table sizes even for Ruby 2.0 users who'll hit extra
583 # allocations here.
584 client.write(@request.response_start_sent ?
585 "100 Continue\r\n\r\nHTTP/1.1 ".freeze :
586 "HTTP/1.1 100 Continue\r\n\r\n".freeze)
587 env.delete('HTTP_EXPECT'.freeze)
588 end
590 # once a client is accepted, it is processed in its entirety here
591 # in 3 easy steps: read request, call app, write app response
592 def process_client(client, ai)
593 @request = Unicorn::HttpRequest.new
594 env = @request.read_headers(client, ai)
596 if early_hints
597 env["rack.early_hints"] = lambda do |headers|
598 e103_response_write(client, headers)
599 end
600 end
602 env["rack.after_reply"] = []
604 status, headers, body = @app.call(env)
606 begin
607 return if @request.hijacked?
609 if 100 == status.to_i
610 e100_response_write(client, env)
611 status, headers, body = @app.call(env)
612 return if @request.hijacked?
613 end
614 @request.headers? or headers = nil
615 http_response_write(client, status, headers, body, @request)
616 ensure
617 body.respond_to?(:close) and body.close
618 end
620 unless client.closed? # rack.hijack may've close this for us
621 client.shutdown # in case of fork() in Rack app
622 client.close # flush and uncork socket immediately, no keepalive
623 end
624 rescue => e
625 handle_error(client, e)
626 ensure
627 env["rack.after_reply"].each(&:call) if env
628 end
630 def nuke_listeners!(readers)
631 # only called from the worker, ordering is important here
632 tmp = readers.dup
633 readers.replace([false]) # ensure worker does not continue ASAP
634 tmp.each { |io| io.close rescue nil } # break out of IO.select
635 end
637 # gets rid of stuff the worker has no business keeping track of
638 # to free some resources and drops all sig handlers.
639 # traps for USR1, USR2, and HUP may be set in the after_fork Proc
640 # by the user.
641 def init_worker_process(worker)
642 worker.atfork_child
643 # we'll re-trap :QUIT later for graceful shutdown iff we accept clients
644 exit_sigs = [ :QUIT, :TERM, :INT ]
645 exit_sigs.each { |sig| trap(sig) { exit!(0) } }
646 exit!(0) if (@sig_queue & exit_sigs)[0]
647 (@queue_sigs - exit_sigs).each { |sig| trap(sig, nil) }
648 trap(:CHLD, 'DEFAULT')
649 @sig_queue.clear
650 proc_name "worker[#{worker.nr}]"
651 START_CTX.clear
652 @workers.clear
654 after_fork.call(self, worker) # can drop perms and create listeners
655 LISTENERS.each { |sock| sock.close_on_exec = true }
657 worker.user(*user) if user.kind_of?(Array) && ! worker.switched
658 @config = nil
659 build_app! unless preload_app
660 @after_fork = @listener_opts = @orig_app = nil
661 readers = LISTENERS.dup
662 readers << worker
663 trap(:QUIT) { nuke_listeners!(readers) }
664 readers
665 end
667 def reopen_worker_logs(worker_nr)
668 logger.info "worker=#{worker_nr} reopening logs..."
669 Unicorn::Util.reopen_logs
670 logger.info "worker=#{worker_nr} done reopening logs"
671 false
672 rescue => e
673 logger.error(e) rescue nil
674 exit!(77) # EX_NOPERM in sysexits.h
675 end
677 def prep_readers(readers)
678 wtr = Unicorn::Waiter.prep_readers(readers)
679 @timeout *= 500 # to milliseconds for epoll, but halved
680 wtr
681 rescue
682 require_relative 'select_waiter'
683 @timeout /= 2.0 # halved for IO.select
684 Unicorn::SelectWaiter.new
685 end
687 # runs inside each forked worker, this sits around and waits
688 # for connections and doesn't die until the parent dies (or is
689 # given a INT, QUIT, or TERM signal)
690 def worker_loop(worker)
691 readers = init_worker_process(worker)
692 waiter = prep_readers(readers)
693 reopen = false
695 # this only works immediately if the master sent us the signal
696 # (which is the normal case)
697 trap(:USR1) { reopen = true }
699 ready = readers.dup
700 @after_worker_ready.call(self, worker)
702 begin
703 reopen = reopen_worker_logs(worker.nr) if reopen
704 worker.tick = time_now.to_i
705 while sock = ready.shift
706 client_ai = sock.accept_nonblock(exception: false)
707 if client_ai != :wait_readable
708 process_client(*client_ai)
709 worker.tick = time_now.to_i
710 end
711 break if reopen
712 end
714 # timeout so we can .tick and keep parent from SIGKILL-ing us
715 worker.tick = time_now.to_i
716 waiter.get_readers(ready, readers, @timeout)
717 rescue => e
718 redo if reopen && readers[0]
719 Unicorn.log_error(@logger, "listen loop error", e) if readers[0]
720 end while readers[0]
721 end
723 # delivers a signal to a worker and fails gracefully if the worker
724 # is no longer running.
725 def kill_worker(signal, wpid)
726 Process.kill(signal, wpid)
727 rescue Errno::ESRCH
728 worker = @workers.delete(wpid) and worker.close rescue nil
729 end
731 # delivers a signal to each worker
732 def kill_each_worker(signal)
733 @workers.keys.each { |wpid| kill_worker(signal, wpid) }
734 end
736 def soft_kill_each_worker(signal)
737 @workers.each_value { |worker| worker.soft_kill(signal) }
738 end
740 # unlinks a PID file at given +path+ if it contains the current PID
741 # still potentially racy without locking the directory (which is
742 # non-portable and may interact badly with other programs), but the
743 # window for hitting the race condition is small
744 def unlink_pid_safe(path)
745 (File.read(path).to_i == $$ and File.unlink(path)) rescue nil
746 end
748 # returns a PID if a given path contains a non-stale PID file,
749 # nil otherwise.
750 def valid_pid?(path)
751 wpid = File.read(path).to_i
752 wpid <= 0 and return
753 Process.kill(0, wpid)
754 wpid
755 rescue Errno::EPERM
756 logger.info "pid=#{path} possibly stale, got EPERM signalling PID:#{wpid}"
757 nil
758 rescue Errno::ESRCH, Errno::ENOENT
759 # don't unlink stale pid files, racy without non-portable locking...
760 end
762 def load_config!
763 loaded_app = app
764 logger.info "reloading config_file=#{config.config_file}"
765 config[:listeners].replace(@init_listeners)
766 config.reload
767 config.commit!(self)
768 soft_kill_each_worker(:QUIT)
769 Unicorn::Util.reopen_logs
770 self.app = @orig_app
771 build_app! if preload_app
772 logger.info "done reloading config_file=#{config.config_file}"
773 rescue StandardError, LoadError, SyntaxError => e
774 Unicorn.log_error(@logger,
775 "error reloading config_file=#{config.config_file}", e)
776 self.app = loaded_app
777 end
779 # returns an array of string names for the given listener array
780 def listener_names(listeners = LISTENERS)
781 listeners.map { |io| sock_name(io) }
782 end
784 def build_app!
785 if app.respond_to?(:arity) && (app.arity == 0 || app.arity == 2)
786 if defined?(Gem) && Gem.respond_to?(:refresh)
787 logger.info "Refreshing Gem list"
788 Gem.refresh
789 end
790 self.app = app.arity == 0 ? app.call : app.call(nil, self)
791 end
792 end
794 def proc_name(tag)
795 $0 = ([ File.basename(START_CTX[0]), tag
796 ]).concat(START_CTX[:argv]).join(' ')
797 end
799 def redirect_io(io, path)
800 File.open(path, 'ab') { |fp| io.reopen(fp) } if path
801 io.sync = true
802 end
804 def inherit_listeners!
805 # inherit sockets from parents, they need to be plain Socket objects
806 inherited = ENV['UNICORN_FD'].to_s.split(',')
807 immortal = []
809 # emulate sd_listen_fds() for systemd
810 sd_pid, sd_fds = ENV.values_at('LISTEN_PID', 'LISTEN_FDS')
811 if sd_pid.to_i == $$ # n.b. $$ can never be zero
812 # 3 = SD_LISTEN_FDS_START
813 immortal = (3...(3 + sd_fds.to_i)).to_a
814 inherited.concat(immortal)
815 end
816 # to ease debugging, we will not unset LISTEN_PID and LISTEN_FDS
818 inherited.map! do |fd|
819 io = Socket.for_fd(fd.to_i)
820 @immortal << io if immortal.include?(fd)
821 set_server_sockopt(io, listener_opts[sock_name(io)])
822 logger.info "inherited addr=#{sock_name(io)} fd=#{io.fileno}"
823 io
824 end
826 config_listeners = config[:listeners].dup
827 LISTENERS.replace(inherited)
829 # we only use generic Socket objects for aggregate Socket#accept_nonblock
830 # return value [ Socket, Addrinfo ]. This allows us to avoid having to
831 # make getpeername(2) syscalls later on to fill in env['REMOTE_ADDR']
832 config_listeners -= listener_names
833 if config_listeners.empty? && LISTENERS.empty?
834 config_listeners << Unicorn::Const::DEFAULT_LISTEN
835 @init_listeners << Unicorn::Const::DEFAULT_LISTEN
836 START_CTX[:argv] << "-l#{Unicorn::Const::DEFAULT_LISTEN}"
837 end
838 NEW_LISTENERS.replace(config_listeners)
839 end
841 # call only after calling inherit_listeners!
842 # This binds any listeners we did NOT inherit from the parent
843 def bind_new_listeners!
844 NEW_LISTENERS.each { |addr| listen(addr) }.clear
845 raise ArgumentError, "no listeners" if LISTENERS.empty?
846 end
848 # try to use the monotonic clock in Ruby >= 2.1, it is immune to clock
849 # offset adjustments and generates less garbage (Float vs Time object)
850 begin
851 Process.clock_gettime(Process::CLOCK_MONOTONIC)
852 def time_now
853 Process.clock_gettime(Process::CLOCK_MONOTONIC)
854 end
855 rescue NameError, NoMethodError
856 def time_now # Ruby <= 2.0
857 Time.now
858 end
859 end
860 end