| blob | a52931af3ee706d197ee4f4d1de18f46ae8f0ad0 |
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
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 @request = Unicorn::HttpRequest.new
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 = {}
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 do |i|
115 Kgio::Pipe.for_fd(i)
116 end
117 worker_data
118 end
119 end
121 # Runs the thing. Returns self so you can run join on it
122 def start
123 inherit_listeners!
124 # this pipe is used to wake us up from select(2) in #join when signals
125 # are trapped. See trap_deferred.
126 @self_pipe.replace(Unicorn.pipe)
127 @master_pid = @worker_data ? Process.ppid : $$
129 # setup signal handlers before writing pid file in case people get
130 # trigger happy and send signals as soon as the pid file exists.
131 # Note that signals don't actually get handled until the #join method
132 @queue_sigs.each { |sig| trap(sig) { @sig_queue << sig; awaken_master } }
133 trap(:CHLD) { awaken_master }
135 # write pid early for Mongrel compatibility if we're not inheriting sockets
136 # This is needed for compatibility some Monit setups at least.
137 # This unfortunately has the side effect of clobbering valid PID if
138 # we upgrade and the upgrade breaks during preload_app==true && build_app!
139 self.pid = config[:pid]
141 build_app! if preload_app
142 bind_new_listeners!
144 spawn_missing_workers
145 self
146 end
148 # replaces current listener set with +listeners+. This will
149 # close the socket if it will not exist in the new listener set
150 def listeners=(listeners)
151 cur_names, dead_names = [], []
152 listener_names.each do |name|
153 if name.start_with?('/')
154 # mark unlinked sockets as dead so we can rebind them
155 (File.socket?(name) ? cur_names : dead_names) << name
156 else
157 cur_names << name
158 end
159 end
160 set_names = listener_names(listeners)
161 dead_names.concat(cur_names - set_names).uniq!
163 LISTENERS.delete_if do |io|
164 if dead_names.include?(sock_name(io))
165 (io.close rescue nil).nil? # true
166 else
167 set_server_sockopt(io, listener_opts[sock_name(io)])
168 false
169 end
170 end
172 (set_names - cur_names).each { |addr| listen(addr) }
173 end
175 def stdout_path=(path); redirect_io($stdout, path); end
176 def stderr_path=(path); redirect_io($stderr, path); end
178 def logger=(obj)
179 Unicorn::HttpRequest::DEFAULTS["rack.logger"] = @logger = obj
180 end
182 def clobber_pid(path)
183 unlink_pid_safe(@pid) if @pid
184 if path
185 fp = begin
186 tmp = "#{File.dirname(path)}/#{rand}.#$$"
187 File.open(tmp, File::RDWR|File::CREAT|File::EXCL, 0644)
188 rescue Errno::EEXIST
189 retry
190 end
191 fp.syswrite("#$$\n")
192 File.rename(fp.path, path)
193 fp.close
194 end
195 end
197 # sets the path for the PID file of the master process
198 def pid=(path)
199 if path
200 if x = valid_pid?(path)
201 return path if pid && path == pid && x == $$
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 unless Kgio::TCPServer === io || Kgio::UNIXServer === io
245 io.autoclose = false
246 io = server_cast(io)
247 end
248 logger.info "listening on addr=#{sock_name(io)} fd=#{io.fileno}"
249 LISTENERS << io
250 io
251 rescue Errno::EADDRINUSE => err
252 logger.error "adding listener failed addr=#{address} (in use)"
253 raise err if tries == 0
254 tries -= 1
255 logger.error "retrying in #{delay} seconds " \
256 "(#{tries < 0 ? 'infinite' : tries} tries left)"
257 sleep(delay)
258 retry
259 rescue => err
260 logger.fatal "error adding listener addr=#{address}"
261 raise err
262 end
263 end
265 # monitors children and receives signals forever
266 # (or until a termination signal is sent). This handles signals
267 # one-at-a-time time and we'll happily drop signals in case somebody
268 # is signalling us too often.
269 def join
270 respawn = true
271 last_check = time_now
273 proc_name 'master'
274 logger.info "master process ready" # test_exec.rb relies on this message
275 if @ready_pipe
276 begin
277 @ready_pipe.syswrite($$.to_s)
278 rescue => e
279 logger.warn("grandparent died too soon?: #{e.message} (#{e.class})")
280 end
281 @ready_pipe = @ready_pipe.close rescue nil
282 end
283 begin
284 reap_all_workers
285 case @sig_queue.shift
286 when nil
287 # avoid murdering workers after our master process (or the
288 # machine) comes out of suspend/hibernation
289 if (last_check + @timeout) >= (last_check = time_now)
290 sleep_time = murder_lazy_workers
291 else
292 sleep_time = @timeout/2.0 + 1
293 @logger.debug("waiting #{sleep_time}s after suspend/hibernation")
294 end
295 maintain_worker_count if respawn
296 master_sleep(sleep_time)
297 when :QUIT # graceful shutdown
298 break
299 when :TERM, :INT # immediate shutdown
300 stop(false)
301 break
302 when :USR1 # rotate logs
303 logger.info "master reopening logs..."
304 Unicorn::Util.reopen_logs
305 logger.info "master done reopening logs"
306 soft_kill_each_worker(:USR1)
307 when :USR2 # exec binary, stay alive in case something went wrong
308 reexec
309 when :WINCH
310 if $stdin.tty?
311 logger.info "SIGWINCH ignored because we're not daemonized"
312 else
313 respawn = false
314 logger.info "gracefully stopping all workers"
315 soft_kill_each_worker(:QUIT)
316 self.worker_processes = 0
317 end
318 when :TTIN
319 respawn = true
320 self.worker_processes += 1
321 when :TTOU
322 self.worker_processes -= 1 if self.worker_processes > 0
323 when :HUP
324 respawn = true
325 if config.config_file
326 load_config!
327 else # exec binary and exit if there's no config file
328 logger.info "config_file not present, reexecuting binary"
329 reexec
330 end
331 end
332 rescue => e
333 Unicorn.log_error(@logger, "master loop error", e)
334 end while true
335 stop # gracefully shutdown all workers on our way out
336 logger.info "master complete"
337 unlink_pid_safe(pid) if pid
338 end
340 # Terminates all workers, but does not exit master process
341 def stop(graceful = true)
342 self.listeners = []
343 limit = time_now + timeout
344 until @workers.empty? || time_now > limit
345 if graceful
346 soft_kill_each_worker(:QUIT)
347 else
348 kill_each_worker(:TERM)
349 end
350 sleep(0.1)
351 reap_all_workers
352 end
353 kill_each_worker(:KILL)
354 end
356 def rewindable_input
357 Unicorn::HttpRequest.input_class.method_defined?(:rewind)
358 end
360 def rewindable_input=(bool)
361 Unicorn::HttpRequest.input_class = bool ?
362 Unicorn::TeeInput : Unicorn::StreamInput
363 end
365 def client_body_buffer_size
366 Unicorn::TeeInput.client_body_buffer_size
367 end
369 def client_body_buffer_size=(bytes)
370 Unicorn::TeeInput.client_body_buffer_size = bytes
371 end
373 def check_client_connection
374 Unicorn::HttpRequest.check_client_connection
375 end
377 def check_client_connection=(bool)
378 Unicorn::HttpRequest.check_client_connection = bool
379 end
381 private
383 # wait for a signal hander to wake us up and then consume the pipe
384 def master_sleep(sec)
385 @self_pipe[0].wait(sec) or return
386 # 11 bytes is the maximum string length which can be embedded within
387 # the Ruby itself and not require a separate malloc (on 32-bit MRI 1.9+).
388 # Most reads are only one byte here and uncommon, so it's not worth a
389 # persistent buffer, either:
390 @self_pipe[0].kgio_tryread(11)
391 end
393 def awaken_master
394 return if $$ != @master_pid
395 @self_pipe[1].kgio_trywrite('.') # wakeup master process from select
396 end
398 # reaps all unreaped workers
399 def reap_all_workers
400 begin
401 wpid, status = Process.waitpid2(-1, Process::WNOHANG)
402 wpid or return
403 if @reexec_pid == wpid
404 logger.error "reaped #{status.inspect} exec()-ed"
405 @reexec_pid = 0
406 self.pid = pid.chomp('.oldbin') if pid
407 proc_name 'master'
408 else
409 worker = @workers.delete(wpid) and worker.close rescue nil
410 @after_worker_exit.call(self, worker, status)
411 end
412 rescue Errno::ECHILD
413 break
414 end while true
415 end
417 # reexecutes the START_CTX with a new binary
418 def reexec
419 if @reexec_pid > 0
420 begin
421 Process.kill(0, @reexec_pid)
422 logger.error "reexec-ed child already running PID:#@reexec_pid"
423 return
424 rescue Errno::ESRCH
425 @reexec_pid = 0
426 end
427 end
429 if pid
430 old_pid = "#{pid}.oldbin"
431 begin
432 self.pid = old_pid # clear the path for a new pid file
433 rescue ArgumentError
434 logger.error "old PID:#{valid_pid?(old_pid)} running with " \
435 "existing pid=#{old_pid}, refusing rexec"
436 return
437 rescue => e
438 logger.error "error writing pid=#{old_pid} #{e.class} #{e.message}"
439 return
440 end
441 end
443 @reexec_pid = fork do
444 listener_fds = listener_sockets
445 ENV['UNICORN_FD'] = listener_fds.keys.join(',')
446 Dir.chdir(START_CTX[:cwd])
447 cmd = [ START_CTX[0] ].concat(START_CTX[:argv])
449 # avoid leaking FDs we don't know about, but let before_exec
450 # unset FD_CLOEXEC, if anything else in the app eventually
451 # relies on FD inheritence.
452 close_sockets_on_exec(listener_fds)
454 # exec(command, hash) works in at least 1.9.1+, but will only be
455 # required in 1.9.4/2.0.0 at earliest.
456 cmd << listener_fds
457 logger.info "executing #{cmd.inspect} (in #{Dir.pwd})"
458 before_exec.call(self)
459 exec(*cmd)
460 end
461 proc_name 'master (old)'
462 end
464 def worker_spawn(worker)
465 listener_fds = listener_sockets
466 env = {}
467 env['UNICORN_FD'] = listener_fds.keys.join(',')
469 listener_fds[worker.to_io.fileno] = worker.to_io
470 listener_fds[worker.master.fileno] = worker.master
472 worker_info = [worker.nr, worker.to_io.fileno, worker.master.fileno]
473 env['UNICORN_WORKER'] = worker_info.join(',')
475 close_sockets_on_exec(listener_fds)
477 Process.spawn(env, START_CTX[0], *START_CTX[:argv], listener_fds)
478 end
480 def listener_sockets
481 listener_fds = {}
482 LISTENERS.each do |sock|
483 sock.close_on_exec = false
484 listener_fds[sock.fileno] = sock
485 end
486 listener_fds
487 end
489 def close_sockets_on_exec(sockets)
490 (3..1024).each do |io|
491 next if sockets.include?(io)
492 io = IO.for_fd(io) rescue next
493 io.autoclose = false
494 io.close_on_exec = true
495 end
496 end
498 # forcibly terminate all workers that haven't checked in in timeout seconds. The timeout is implemented using an unlinked File
499 def murder_lazy_workers
500 next_sleep = @timeout - 1
501 now = time_now.to_i
502 @workers.dup.each_pair do |wpid, worker|
503 tick = worker.tick
504 0 == tick and next # skip workers that haven't processed any clients
505 diff = now - tick
506 tmp = @timeout - diff
507 if tmp >= 0
508 next_sleep > tmp and next_sleep = tmp
509 next
510 end
511 next_sleep = 0
512 logger.error "worker=#{worker.nr} PID:#{wpid} timeout " \
513 "(#{diff}s > #{@timeout}s), killing"
514 kill_worker(:KILL, wpid) # take no prisoners for timeout violations
515 end
516 next_sleep <= 0 ? 1 : next_sleep
517 end
519 def after_fork_internal
520 @self_pipe.each(&:close).clear # this is master-only, now
521 @ready_pipe.close if @ready_pipe
522 Unicorn::Configurator::RACKUP.clear
523 @ready_pipe = @init_listeners = @before_exec = @before_fork = nil
525 # The OpenSSL PRNG is seeded with only the pid, and apps with frequently
526 # dying workers can recycle pids
527 OpenSSL::Random.seed(rand.to_s) if defined?(OpenSSL::Random)
528 end
530 def spawn_missing_workers
531 if @worker_data
532 worker = Unicorn::Worker.new(*@worker_data)
533 after_fork_internal
534 worker_loop(worker)
535 exit
536 end
538 worker_nr = -1
539 until (worker_nr += 1) == @worker_processes
540 @workers.value?(worker_nr) and next
541 worker = Unicorn::Worker.new(worker_nr)
542 before_fork.call(self, worker)
544 pid = @worker_exec ? worker_spawn(worker) : fork
546 unless pid
547 after_fork_internal
548 worker_loop(worker)
549 exit
550 end
552 @workers[pid] = worker
553 worker.atfork_parent
554 end
555 rescue => e
556 @logger.error(e) rescue nil
557 exit!
558 end
560 def maintain_worker_count
561 (off = @workers.size - worker_processes) == 0 and return
562 off < 0 and return spawn_missing_workers
563 @workers.each_value { |w| w.nr >= worker_processes and w.soft_kill(:QUIT) }
564 end
566 # if we get any error, try to write something back to the client
567 # assuming we haven't closed the socket, but don't get hung up
568 # if the socket is already closed or broken. We'll always ensure
569 # the socket is closed at the end of this function
570 def handle_error(client, e)
571 code = case e
572 when EOFError,Errno::ECONNRESET,Errno::EPIPE,Errno::ENOTCONN
573 # client disconnected on us and there's nothing we can do
574 when Unicorn::RequestURITooLongError
575 414
576 when Unicorn::RequestEntityTooLargeError
577 413
578 when Unicorn::HttpParserError # try to tell the client they're bad
579 400
580 else
581 Unicorn.log_error(@logger, "app error", e)
582 500
583 end
584 if code
585 client.kgio_trywrite(err_response(code, @request.response_start_sent))
586 end
587 client.close
588 rescue
589 end
591 def e100_response_write(client, env)
592 # We use String#freeze to avoid allocations under Ruby 2.1+
593 # Not many users hit this code path, so it's better to reduce the
594 # constant table sizes even for 1.9.3-2.0 users who'll hit extra
595 # allocations here.
596 client.write(@request.response_start_sent ?
597 "100 Continue\r\n\r\nHTTP/1.1 ".freeze :
598 "HTTP/1.1 100 Continue\r\n\r\n".freeze)
599 env.delete('HTTP_EXPECT'.freeze)
600 end
602 # once a client is accepted, it is processed in its entirety here
603 # in 3 easy steps: read request, call app, write app response
604 def process_client(client)
605 status, headers, body = @app.call(env = @request.read(client))
607 begin
608 return if @request.hijacked?
610 if 100 == status.to_i
611 e100_response_write(client, env)
612 status, headers, body = @app.call(env)
613 return if @request.hijacked?
614 end
615 @request.headers? or headers = nil
616 http_response_write(client, status, headers, body, @request)
617 ensure
618 body.respond_to?(:close) and body.close
619 end
621 unless client.closed? # rack.hijack may've close this for us
622 client.shutdown # in case of fork() in Rack app
623 client.close # flush and uncork socket immediately, no keepalive
624 end
625 rescue => e
626 handle_error(client, e)
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 self.timeout /= 2.0 # halve it for select()
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 rescue => e
672 logger.error(e) rescue nil
673 exit!(77) # EX_NOPERM in sysexits.h
674 end
676 # runs inside each forked worker, this sits around and waits
677 # for connections and doesn't die until the parent dies (or is
678 # given a INT, QUIT, or TERM signal)
679 def worker_loop(worker)
680 ppid = @master_pid
681 readers = init_worker_process(worker)
682 nr = 0 # this becomes negative if we need to reopen logs
684 # this only works immediately if the master sent us the signal
685 # (which is the normal case)
686 trap(:USR1) { nr = -65536 }
688 ready = readers.dup
689 @after_worker_ready.call(self, worker)
691 begin
692 nr < 0 and reopen_worker_logs(worker.nr)
693 nr = 0
694 worker.tick = time_now.to_i
695 tmp = ready.dup
696 while sock = tmp.shift
697 # Unicorn::Worker#kgio_tryaccept is not like accept(2) at all,
698 # but that will return false
699 if client = sock.kgio_tryaccept
700 process_client(client)
701 nr += 1
702 worker.tick = time_now.to_i
703 end
704 break if nr < 0
705 end
707 # make the following bet: if we accepted clients this round,
708 # we're probably reasonably busy, so avoid calling select()
709 # and do a speculative non-blocking accept() on ready listeners
710 # before we sleep again in select().
711 unless nr == 0
712 tmp = ready.dup
713 redo
714 end
716 ppid == Process.ppid or return
718 # timeout used so we can detect parent death:
719 worker.tick = time_now.to_i
720 ret = IO.select(readers, nil, nil, @timeout) and ready = ret[0]
721 rescue => e
722 redo if nr < 0 && readers[0]
723 Unicorn.log_error(@logger, "listen loop error", e) if readers[0]
724 end while readers[0]
725 end
727 # delivers a signal to a worker and fails gracefully if the worker
728 # is no longer running.
729 def kill_worker(signal, wpid)
730 Process.kill(signal, wpid)
731 rescue Errno::ESRCH
732 worker = @workers.delete(wpid) and worker.close rescue nil
733 end
735 # delivers a signal to each worker
736 def kill_each_worker(signal)
737 @workers.keys.each { |wpid| kill_worker(signal, wpid) }
738 end
740 def soft_kill_each_worker(signal)
741 @workers.each_value { |worker| worker.soft_kill(signal) }
742 end
744 # unlinks a PID file at given +path+ if it contains the current PID
745 # still potentially racy without locking the directory (which is
746 # non-portable and may interact badly with other programs), but the
747 # window for hitting the race condition is small
748 def unlink_pid_safe(path)
749 (File.read(path).to_i == $$ and File.unlink(path)) rescue nil
750 end
752 # returns a PID if a given path contains a non-stale PID file,
753 # nil otherwise.
754 def valid_pid?(path)
755 wpid = File.read(path).to_i
756 wpid <= 0 and return
757 Process.kill(0, wpid)
758 wpid
759 rescue Errno::EPERM
760 logger.info "pid=#{path} possibly stale, got EPERM signalling PID:#{wpid}"
761 nil
762 rescue Errno::ESRCH, Errno::ENOENT
763 # don't unlink stale pid files, racy without non-portable locking...
764 end
766 def load_config!
767 loaded_app = app
768 logger.info "reloading config_file=#{config.config_file}"
769 config[:listeners].replace(@init_listeners)
770 config.reload
771 config.commit!(self)
772 soft_kill_each_worker(:QUIT)
773 Unicorn::Util.reopen_logs
774 self.app = @orig_app
775 build_app! if preload_app
776 logger.info "done reloading config_file=#{config.config_file}"
777 rescue StandardError, LoadError, SyntaxError => e
778 Unicorn.log_error(@logger,
779 "error reloading config_file=#{config.config_file}", e)
780 self.app = loaded_app
781 end
783 # returns an array of string names for the given listener array
784 def listener_names(listeners = LISTENERS)
785 listeners.map { |io| sock_name(io) }
786 end
788 def build_app!
789 if app.respond_to?(:arity) && (app.arity == 0 || app.arity == 2)
790 if defined?(Gem) && Gem.respond_to?(:refresh)
791 logger.info "Refreshing Gem list"
792 Gem.refresh
793 end
794 self.app = app.arity == 0 ? app.call : app.call(nil, self)
795 end
796 end
798 def proc_name(tag)
799 $0 = ([ File.basename(START_CTX[0]), tag
800 ]).concat(START_CTX[:argv]).join(' ')
801 end
803 def redirect_io(io, path)
804 File.open(path, 'ab') { |fp| io.reopen(fp) } if path
805 io.sync = true
806 end
808 def inherit_listeners!
809 # inherit sockets from parents, they need to be plain Socket objects
810 # before they become Kgio::UNIXServer or Kgio::TCPServer
811 inherited = ENV['UNICORN_FD'].to_s.split(',')
813 # emulate sd_listen_fds() for systemd
814 sd_pid, sd_fds = ENV.values_at('LISTEN_PID', 'LISTEN_FDS')
815 if sd_pid.to_i == $$ # n.b. $$ can never be zero
816 # 3 = SD_LISTEN_FDS_START
817 inherited.concat((3...(3 + sd_fds.to_i)).to_a)
818 end
819 # to ease debugging, we will not unset LISTEN_PID and LISTEN_FDS
821 inherited.map! do |fd|
822 io = Socket.for_fd(fd.to_i)
823 io.autoclose = false
824 io = server_cast(io)
825 set_server_sockopt(io, listener_opts[sock_name(io)])
826 logger.info "inherited addr=#{sock_name(io)} fd=#{io.fileno}"
827 io
828 end
830 config_listeners = config[:listeners].dup
831 LISTENERS.replace(inherited)
833 # we start out with generic Socket objects that get cast to either
834 # Kgio::TCPServer or Kgio::UNIXServer objects; but since the Socket
835 # objects share the same OS-level file descriptor as the higher-level
836 # *Server objects; we need to prevent Socket objects from being
837 # garbage-collected
838 config_listeners -= listener_names
839 if config_listeners.empty? && LISTENERS.empty?
840 config_listeners << Unicorn::Const::DEFAULT_LISTEN
841 @init_listeners << Unicorn::Const::DEFAULT_LISTEN
842 START_CTX[:argv] << "-l#{Unicorn::Const::DEFAULT_LISTEN}"
843 end
844 NEW_LISTENERS.replace(config_listeners)
845 end
847 # call only after calling inherit_listeners!
848 # This binds any listeners we did NOT inherit from the parent
849 def bind_new_listeners!
850 NEW_LISTENERS.each { |addr| listen(addr) }.clear
851 raise ArgumentError, "no listeners" if LISTENERS.empty?
852 end
854 # try to use the monotonic clock in Ruby >= 2.1, it is immune to clock
855 # offset adjustments and generates less garbage (Float vs Time object)
856 begin
857 Process.clock_gettime(Process::CLOCK_MONOTONIC)
858 def time_now
859 Process.clock_gettime(Process::CLOCK_MONOTONIC)
860 end
861 rescue NameError, NoMethodError
862 def time_now # Ruby <= 2.0
863 Time.now
864 end
865 end
866 end